Search

Studies of the immune landscape led to breakthrough trials of programmed death-1 (PD-1) inhibitors for recurrent/metastatic head and neck squamous cell carcinoma therapy. This study investigated the timing, influence of somatic copy-number alterations (SCNAs), and clinical implications of PD-L1 and immune-cell patterns in oral precancer (OPC).The authors evaluated spatial CD3, CD3/8, and CD68 density (cells/mmEpithelial, but not CD68 immune-cell, PD-L1 expression was detected in 28% of OPCs, correlated with immune-cell infiltration, 9p21.3 loss of heterozygosity (LOH), and inferior oral cancer-free survival (OCFS), notably in OPCs with low CD3/8 cell density, dysplasia, and/or 9p21.3 LOH. High CD3/8 cell density in dysplastic lesions predicted better OCFS and eliminated the excess risk associated with prior oral cancer and dysplasia. PD-L1 and CD3/8 patterns revealed inferior OCFS in PD-L1 high intrinsic induction and dysplastic immune-cold subgroups.This report provides spatial insight into the immune landscape and drivers of OPCs, and a publicly available immunogenomic data set for future precancer interrogation. The data suggest that 9p21.3 LOH triggers an immune-hot inflammatory phenotype; whereas increased 9p deletion size encompassing CD274 at 9p24.1 may contribute to CD3/8 and PD-L1 depletion during invasive transition. The inferior OCFS in PD-L1-high, immune-cold OPCs support the development of T-cell recruitment strategies.

The majority of TP53 missense mutations identified in cancer patients are in the DNA-binding domain and are characterized as either structural or contact mutations. These missense mutations exhibit inhibitory effects on wild-type p53 activity. More importantly, these mutations also demonstrate gain-of-function (GOF) activities characterized by increased metastasis, poor prognosis, and drug resistance. To better understand the activities by which TP53 mutations, identified in Li–Fraumeni syndrome, contribute to tumorigenesis, we generated mice harboring a novel germline Trp53R245W allele (contact mutation) and compared them with existing models with Trp53R172H (structural mutation) and Trp53R270H (contact mutation) alleles. Thymocytes from heterozygous mice showed that all three hotspot mutations exhibited similar inhibitory effects on wild-type p53 transcription in vivo, and tumors from these mice had similar levels of loss of heterozygosity. However, the overall survival of Trp53R245W/+ and Trp53R270H/+ mice, but not Trp53R172H/+ mice, was significantly shorter than that of Trp53+/− mice, providing strong evidence for p53-mutant–specific GOF contributions to tumor development. Furthermore, Trp53R245W/+ and Trp53R270H/+ mice had more osteosarcoma metastases than Trp53R172H/+ mice, suggesting that these two contact mutants have stronger GOF in driving osteosarcoma metastasis. Transcriptomic analyses using RNA sequencing data from Trp53R172H/+, Trp53R245W/+, and Trp53R270H/+ primary osteosarcomas in comparison with Trp53+/– indicated that GOF of the three mutants was mediated by distinct pathways. Thus, both the inhibitory effect of mutant over wild-type p53 and GOF activities of mutant p53 contributed to tumorigenesis in vivo. Targeting p53 mutant–specific pathways may be important for therapeutic outcomes in osteosarcoma. Significance: p53 hotspot mutants inhibit wild-type p53 similarly but differ in their GOF activities, with stronger tumor-promoting activity in contact mutants and distinct protein partners of each mutant driving tumorigenesis and metastasis.

PURPOSE: The combination of cisplatin and radiation or cetuximab and radiation improves overall survival of patients with locoregionally advanced head and neck carcinoma. NRG Oncology conducted a phase 3 trial to test the hypothesis that adding cetuximab to radiation and cisplatin would improve progression-free survival (PFS). METHODS AND MATERIALS: Eligible patients with American Joint Committee on Cancer sixth edition stage T2 N2a-3 M0 or T3–4 N0–3 M0 were accrued from November 2005 to March 2009 and randomized to receive radiation and cisplatin without (arm A) or with (arm B) cetuximab. Outcomes were correlated with patient and tumor features. Late reactions were scored using Common Terminology Criteria for Adverse Events (version 3). RESULTS: Of 891 analyzed patients, 452 with a median follow-up of 10.1 years were alive at analysis. The addition of cetuximab did not improve PFS (hazard ratio [HR], 1.06; 95% confidence interval [CI], 0.89–1.26; P = .74), with 10-year estimates of 43.6% (95% CI, 38.8–48.4) for arm A and 40.2% (95% CI, 35.4–45.0) for arm B. Cetuximab did not reduce locoregional failure (HR, 1.21; 95% CI, 0.95–1.53; P = .94) or distant metastasis (HR, 0.79; 95% CI, 0.54–1.14; P = .10) or improve overall survival (HR, 0.97; 95% CI, 0.80–1.16; P = .36). Cetuximab did not appear to improve PFS in either p16-positive oropharynx (HR, 1.30; 95% CI, 0.87–1.93) or p16-negative oropharynx or nonoropharyngeal primary (HR, 0.94; 95% CI, 0.73–1.21). Grade 3 to 4 late toxicity rates were 57.4% in arm A and 61.3% in arm B (P = .26). CONCLUSIONS: With a median follow-up of more than 10 years, this updated report confirms the addition of cetuximab to radiation therapy and cisplatin did not improve any measured outcome in the entire cohort or when stratifying by p16 status.

Salivary gland cancers (SGCs) are rare yet aggressive malignancies with significant histological heterogeneity, which has made prediction of prognosis and development of targeted therapies challenging. In majority of patients, local recurrence and/or distant metastasis are common and systemic treatments have minimal impact on survival. Therefore, identification of novel targets for treatment that can also be used as predictors of recurrence for multiple histological subtypes of SGCs is an area of unmet need. In this study, we developed a novel transgenic mouse model of SGC, efficiently recapitulating the major histological subtype (adenocarcinomas of the parotid gland) of human SGC. CDK2 knock out (KO) mice crossed with MMTV-low molecular weight forms of cyclin E (LMW-E) mice generated the transgenic mouse models of SGC, which arise in the parotid region of the salivary gland, similar to the common site of origin seen in human SGCs. To identify the CDK2 independent catalytic partner(s) of LMW-E, we used LMW-E expressing cell lines in mass spectrometric analysis and subsequent biochemical validation in pull down assays. These studies revealed that in the absence of CDK2, LMW-E preferentially binds to CDK5. Molecular targeting of CDK5, using siRNA, resulted in inhibition of cell proliferation of human SGCs overexpressing LMW-E. We also provide clinical evidence of significant association of LMW-E/CDK5 co-expression and decreased recurrence free survival in human SGC. Immunohistochemical analysis of LMW-E and CDK5 in 424 patients representing each of the four major histological subtypes of human salivary cancers (Aci, AdCC, MEC, and SDC) revealed that LMW-E and CDK5 are concordantly (positive/positive or negative/negative) expressed in 70% of these patients. The co-expression of LMW-E/CDK5 (both positive) robustly predicts the likelihood of recurrence, regardless of the histological classification of these tumors. Collectively, our results suggest that CDK5 is a novel and targetable biomarker for the treatment of patients with SGC presenting with LMW-E overexpressing tumors.

Purpose: Salivary gland adenoid cystic carcinoma (ACC) has heterogeneous clinical behavior. Currently, all patients are treated uniformly, and no standard-of-care systemic therapy exists for metastatic ACC. We conducted an integrated proteogenomic analyses of ACC tumors to identify dysregulated pathways and propose a classification with therapeutic implications. Experimental Design: RNA/DNA sequencing of 54 flash-frozen salivary ACCs and reverse phase protein array (RPPA) in 38 specimens were performed, with validation by Western blotting and/or IHC. Three independent ACC cohorts were used for validation. Results: Both unbiased RNA sequencing (RNA-seq) and RPPA analysis revealed two molecular subtypes: ACC-I (37%) and ACC-II (63%). ACC-I had strong upregulation of MYC, MYC target genes, and mRNA splicing, enrichment of NOTCH-activating mutations, and dramatically worse prognosis. ACC-II exhibited upregulation of TP63 and receptor tyrosine kinases (AXL, MET, and EGFR) and less aggressive clinical course. TP63 and MYC were sufficient to assign tumors to ACC subtypes, which was validated in one independent cohort by IHC and two additional independent cohorts by RNA-seq. Furthermore, IHC staining for MYC and P63 protein levels can be used to identify ACC subtypes, enabling rapid clinical deployment to guide therapeutic decisions. Our data suggest a model in which ACC-I is driven by MYC signaling through either NOTCH mutations or direct amplification, which in turn suppress P63 signaling observed in ACC-II, producing unique therapeutic vulnerabilities for each subtype. Conclusions: Cooccurrence of multiple actionable protein/pathways alterations in each subtype indicates unique therapeutic vulnerabilities and opportunities for optimal combination therapy for this understudied and heterogeneous disease.

Background The last revision of the American Joint Committee on Cancer (AJCC) Cancer Staging Manual included a specific system for cutaneous squamous cell carcinoma (CSCC) of the head and neck. Here, we assessed the prognostic performance of six candidate modified T-classification models in head and neck CSCC patients. Methods Analysis of 916 patients with head and neck CSCC given treatment with curative intent at The University of Texas MD Anderson Cancer Center between 1995 and 2019 was performed. The main outcome was disease-specific survival (DSS), and the impact of depth of invasion (DOI) was analyzed using multivariable regression models. Candidate models were developed using the optimal DOI cut points for each AJCC T classification based on goodness of fit of the model and the simplicity of the model. Staging systems were compared using Harrell's concordance index. Results Median age was 70 years (range, 19–97years) and median follow-up time of 22 months (range, 1–250months). The median DOI was 6.0 mm (range, 0.1–70.0 mm). The five-year DSS rate was 80.7% (95%CI, 77.4–83.7%). We found significant association between DOI (hazard ratio, 1.21 [95%CI: 1.01–1.43]) and DSS on multivariable analysis. Based on a low Akaike information criterion score, improvement in the concordance index, and Kaplan–Meier curves, model 6 surpassed the AJCC staging system. Conclusions Incorporation of DOI in the current AJCC staging system improves discrimination of T classifications in head and neck CSCC patients. Lay summary The current staging system for head and neck cutaneous squamous cell carcinoma demonstrates wide prognostic variability and provides suboptimal risk stratification. Incorporation of depth of invasion in the T-classification system improves risk prediction and patient counseling. Precis We propose improved head and neck cutaneous squamous cell carcinoma T staging that will include depth of invasion and should be considered in future versions of the American Joint Committee on Cancer after external validation.

Background The prognostic performance of the recently updated American Joint Committee on Cancer lymph node classification of cutaneous head and neck squamous cell carcinoma (HNSCC) has not been validated. The objective of this study was to assess the prognostic role of extranodal extension (ENE) in cutaneous HNSCC. Methods This was a retrospective analysis of 1258 patients with cutaneous HNSCC who underwent surgery with or without adjuvant therapy between 1995 and 2019 at The University of Texas MD Anderson Cancer Center. The primary outcome was disease-specific survival (DSS). Local, regional, and distant metastases-free survival were secondary outcomes. Recursive partitioning analysis (RPA) and a Cox proportional hazards regression model were used to assess the fitness of staging models. Results No significant differences in 5-year DSS were observed between patients with pathologic lymph node-negative (pN0) disease (67.4%) and those with pN-positive/ENE-negative disease (68.2%; hazard ratio, 1.02; 95% CI, 0.61-1.79) or between patients with pN-positive/ENE-negative disease and those with pN-positive/ENE-positive disease (52.7%; hazard ratio, 0.57; 95% CI, 0.31-1.01). The RPA-derived model achieved better stratification between high-risk patients (category III, ENE-positive with >2 positive lymph nodes) and low-risk patients (category I, pN0; category II, ENE-positive/pN1 and ENE-negative with >2 positive lymph nodes). The performance of the RPA-derived model was better than that of the pathologic TNM classification (Akaike information criterion score, 1167 compared with 1176; Bayesian information criterion score, 1175 compared with 1195). Conclusions The number of metastatic lymph nodes and the presence of ENE are independent prognostic factors for DSS in cutaneous HNSCC, and incorporation of these factors in staging systems improves the performance of the American Joint Committee on Cancer lymph node classification.

Purpose: To determine the expression of glucocorticoid receptor (GR) and androgen receptor (AR) in salivary duct carcinoma (SDC) and to analyze the role of these proteins in the development and management of this disease entity. Experimental Design: We performed a phenotypic assessment of GR and AR localization and expression, and determined their association with clinicopathologic factors in 67 primary SDCs. In vitro functional and response analysis of SDC cell lines was also performed. Results: Of the 67 primary tumors, 12 (18%) overexpressed GR protein, 30 (45%) had constitutive expression, and 25 (37%) had complete loss of expression. Reciprocal GR and AR expression was found in 32 (48%) tumors, concurrent constitutive GR and AR expression in 23 (34%), and simultaneous loss of both receptors and high GR with AR expressions were found in 12 (18%). GR overexpression was significantly associated with worse clinical outcomes. In vitro ligand-independent AR activation was observed in both male- and female-derived cell lines. GR antagonist treatment resulted in decreased cell proliferation and survival in GR-overexpressing cells, irrespective of AR status. Reciprocal GR- and AR-knockdown experiments revealed an independent interaction. Conclusions: Our study, for the first time, demonstrates differential GR and AR expressions, autonomous GR and AR activation, and ligand-independent AR expression and activation in SDC cells. The findings provide critical information on the roles of GR and AR steroid receptors in SDC tumorigenesis and development of biomarkers to guide targeted steroid receptor therapy trials in patients with these tumors.

The solid tumour microenvironment includes nerve fibres that arise from the peripheral nervous system(1,2). Recent work indicates that newly formed adrenergic nerve fibres promote tumour growth, but the origin of these nerves and the mechanism of their inception are unknown(1,3). Here, by comparing the transcriptomes of cancer-associated trigeminal sensory neurons with those of endogenous neurons in mouse models of oral cancer, we identified an adrenergic differentiation signature. We show that loss of TP53 leads to adrenergic transdifferentiation of tumour-associated sensory nerves through loss of the microRNA miR-34a. Tumour growth was inhibited by sensory denervation or pharmacological blockade of adrenergic receptors, but not by chemical sympathectomy of pre-existing adrenergic nerves. A retrospective analysis of samples from oral cancer revealed that p53 status was associated with nerve density, which was in turn associated with poor clinical outcomes. This crosstalk between cancer cells and neurons represents mechanism by which tumour-associated neurons are reprogrammed towards an adrenergic phenotype that can stimulate tumour progression, and is a potential target for anticancer therapy.

Adenoid cystic carcinoma (ACC) is an aggressive malignancy that most often arises in salivary or lacrimal glands but can also occur in other tissues. We used optimized RNA-sequencing to analyze the transcriptomes of 113 ACC tumor samples from salivary gland, lacrimal gland, breast or skin. ACC tumors from different organs displayed remarkedly similar transcription profiles, and most harbored translocations in the MYB or MYBL1 genes, which encode oncogenic transcription factors that may induce dramatic genetic and epigenetic changes leading to a dominant ‘ACC phenotype’. Further analysis of the 56 salivary gland ACC tumors led to the identification of three distinct groups of patients, based on gene expression profiles, including one group with worse survival. We tested whether this new cohort could be used to validate a biomarker developed previously with a different set of 68 ACC tumor samples. Indeed, a 49-gene classifier developed with the earlier cohort correctly identified 98% of the poor survival patients from the new set, and a 14-gene classifier was almost as accurate. These validated biomarkers form a platform to identify and stratify high-risk ACC patients into clinical trials of targeted therapies for sustained clinical response.

BACKGROUND Salivary duct carcinoma (SDC) and adenocarcinoma, not otherwise specified (adeno-NOS), are rare salivary gland cancers. Data on the efficacy of systemic therapy for these diseases are limited. METHODS Data were retrospectively collected from patients seen at The University of Texas MD Anderson Cancer Center during 1990 to 2020. Objective response rate (ORR) was assessed per RECIST v1.1. Recurrence-free survival (RFS), progression-free survival (PFS), and overall survival (OS) were assessed by Kaplan-Meier method. Cox regression model was performed to identify predictors of survival. RESULTS The analysis included 200 patients (110 with SDC and 90 with adeno-NOS); 77% had androgen-receptor-positive tumors and 47% had HER2-positive (2+-3+) tumors. Most patients without metastasis at diagnosis underwent surgery (98%) and postoperative radiotherapy (87%). Recurrence rate was 55%, and the median RFS was 2 years. Nodal involvement and positive surgical margins were associated with recurrence (P < .005). Among patients with stage IVA-B disease, addition of systemic therapy to local therapy increased OS (P = .049). The most-used palliative-systemic-therapy regimen was platinum doublet ± trastuzumab. For first-line therapy, the ORR and median PFS were 33% and 5.76 months, respectively, and for second-line therapy the ORR and median PFS were 25% and 5.3 months, respectively. ORR and PFS were higher with HER2-targeting agents. Median OS was 5 years overall and 2 years for metastatic disease. Older age and higher stage were associated with worse OS. CONCLUSION Adding systemic therapy to local therapy may improve outcomes of patients with locoregionally advanced SDC or adeno-NOS. Except for HER2-targeted therapy, response to palliative systemic therapy is limited. These findings may be used as a benchmark for future drug development.

Background PI3K/mTOR inhibition leads to apoptosis of NOTCH1-mutant head and neck squamous cell carcinoma (HNSCC) cells. We tested the efficacy of the PI3K/mTOR inhibitor bimiralisib in patients with NOTCH1-mutant HNSCC. Methods Patients with recurrent/metastatic NOTCH1-mutant HNSCC who had progressed during chemotherapy and immunotherapy received bimiralisib until unacceptable toxicity or progression. To assess whether NOTCH1 mutations can be detected in blood, we measured circulating tumor DNA (ctDNA). To assess activated NOTCH1 protein levels, we quantitated cleaved NOTCH1 (cl-NOTCH) by immunohistochemistry. Results Eight patients were treated, and 6 were evaluable for response. The objective response rate was 17%. For all 8 patients, median progression-free and overall survival was 5 and 7 months, respectively. Bimiralisib was well tolerated, with expected hyperglycemia. Pharmacokinetic values were consistent with published studies. NOTCH1 mutations were detected in 83.3% of ctDNA. Staining for tumor cl-NOTCH1 was negative. The trial closed early due to sponsor insolvency. Conclusion Although the trial was small, outcomes with bimiralisib were better than the historical standard of care; Results will need to be confirmed in a larger trial. The lack of cl-NOTCH1 was consistent with loss-of-function mutations and validated our mutation function algorithm. The ability to detect NOTCH1 mutations in blood will help future studies. (ClinicalTrials.gov Identifier: NCT03740100).

Adenoid cystic carcinoma (ACC) is an aggressive head and neck malignancy characterized by a t (6;9) translocation resulting in an MYB–NFIB gene fusion or, more rarely, an MYBL1 fusion. The true frequency and clinical significance of these alterations are still unclear. Here, we have used tissue microarrays and analyzed 391 ACCs and 647 non-ACC salivary neoplasms to study the prevalence, expression, and clinical significance of MYB/MYBL1 alterations by FISH and immunohistochemistry. Alterations of MYB or MYBL1 were found in 78% of the cases, of which 62% had MYB alterations and 16% had MYBL1 rearrangements. Overexpression of MYB/MYBL1 oncoproteins was detected in 93% of the cases. MYB split signal, seen in 39% of the cases, was specific for ACC and not encountered in non-ACC salivary tumors. Loss of the 3′-part of MYB was enriched in grade 3 tumors and was a significant independent prognostic biomarker for overall survival in multivariate analyses. We hypothesize that loss of the 3′-part of MYB results from an unbalanced t(6;9) leading to an MYB–NFIB fusion with concomitant loss of the segment distal to the MYB breakpoint in 6q23.3. Our study provides new knowledge about the prevalence and clinical significance of MYB/MYBL1 alterations and indicates the presence of genes with tumor suppressive functions in 6q23.3-qter that contribute to poor prognosis and short overall survival in ACC.

Purpose: In locoregionally advanced, resectable cutaneous squamous cell carcinoma of the head and neck (CSCC-HN), surgery followed by radiotherapy is standard but can be cosmetically and functionally devastating, and many patients will have recurrence. Patients and Methods: Newly diagnosed or recurrent stage III–IVA CSCC-HN patients amenable to curative-intent surgery received two cycles of neoadjuvant PD-1 inhibition. The primary endpoint was ORR per RECIST 1.1. Secondary endpoints included pathologic response [pathologic complete response (pCR) or major pathologic response (MPR; ≤10% viable tumor)], safety, DSS, DFS, and OS. Exploratory endpoints included immune biomarkers of response. Results: Of 20 patients enrolled, 7 had recurrent disease. While only 6 patients [30%; 95% confidence interval (CI), 11.9–54.3] had partial responses by RECIST, 15 patients (75%; 95% CI, 50.9–91.3) had a pCR (n = 11) or MPR (n = 4). No SAEs ocurred during or after the neoadjuvant treatment. At a median follow-up of 22.6 months (95% CI, 21.7–26.1), one patient progressed and died, one died without disease, and two developed recurrence. The 12-month DSS, DFS, and OS rates were 95% (95% CI, 85.9–100), 89.5% (95% CI, 76.7–100), and 95% (95% CI, 85.9–100), respectively. Gene expression studies revealed an inflamed tumor microenvironment in patients with pCR or MPR, and CyTOF analyses demonstrated a memory CD8+ T-cell cluster enriched in patients with pCR. Conclusions: Neoadjuvant immunotherapy in locoregionally advanced, resectable CSCC-HN is safe and induces a high pathologic response rate. Pathologic responses were associated with an inflamed tumor microenvironment.

Background The survival benefit of elective neck dissection (END) for patients with cutaneous squamous cell carcinoma (cSCC) of the head and neck and no evidence of regional metastasis (cN0) has never been reported. The aim of this study was to determine the effect of END on patient survival. Methods The authors included patients with head and neck cSCC who had undergone primary surgery from 1995 to 2017. The primary end point was survival, and the secondary end points were the incidence of occult regional disease and regional disease control. To assess the impact of END on survival, the authors used multivariable Cox proportional hazards models with propensity score and matching techniques for internal validation. Results A total of 1111 patients presented with no evidence of nodal disease; 173 had END, and 938 were observed. Adjuvant radiotherapy to the neck was administered to 101 patients (9%). END resulted in a 5-year overall survival rate of 52%, whereas the rate was 63% in the observation group (P = .003 [log-rank]). The 5-year disease-free survival rate for patients undergoing END was similar to that for the observation group (73% vs 75%; P = .429). A multivariate regression model showed that the performance of END was not associated with improved rates of overall, disease-specific, or disease-free survival; similarly, among patients with advanced disease (T3-4), those who underwent END did not have improved survival rates. Conclusions Among patients with cSCC of the head and neck, observation of the neck nodes resulted in noninferior survival rates in comparison with END at the time of primary surgery. Further studies are required to elucidate the role of END in patients with advanced disease.

Simple Summary Immune checkpoint blockade with anti-PD-1 antibodies blocks the development of oral squamous cell carcinomas (OSCCs) in preclinical models. Understanding whether the genetic alterations that accumulate during oral cancer development affect the response to PD-1 inhibitors is critical to identify patients who may benefit from immunoprevention interventions. Using genetically engineered mouse models that develop carcinogen-induced oral tumors that differ on the mutational status of the p53 gene, we demonstrated that expression of gain-of-function mutant p53 in the epithelial cells of the oral lesions promotes resistance to the immunopreventive effects of anti-PD-1. These novel findings could guide patient-specific strategies for oral cancer immunoprevention based on p53 profiling. Abstract Oral squamous cell carcinoma (OSCC) develops through the multistep malignant progression of squamous epithelium. This process can be prevented by PD-1 blockade in a mouse model for oral carcinogenesis. OSCCs exhibit a high incidence of p53 mutations that confer oncogenic gain-of-function (GOF) activities that promote resistance to standard therapies and poor clinical outcomes. To determine whether epithelial p53 mutations modulate anti-PD-1-mediated oral cancer immunoprevention, we generated mouse models for oral carcinogenesis by exposing mice carrying epithelial-specific p53 mutations to the carcinogen 4NQO. Consistent with the oncogenic functions of mutant p53, mice with OSCCs expressing the p53R172H GOF mutation developed higher metastasis rates than mice with loss-of-function (LOF) p53 deletion or with wild-type p53. Throughout oral cancer progression, pre-invasive and invasive lesions showed a gradual increase in T-cell infiltration, recruitment of immunosuppressive regulatory T-cells (Tregs), and induction of PD-1/PD-L1 immune checkpoint proteins. Notably, while PD-1 blockade prevented the development of OSCCs in mice with wild-type p53 or p53 deletion, GOF p53R172H abrogated the immunopreventive effects of anti-PD-1, associated with upregulation of IL17 signaling and depletion of exhausted CD8 cells in the microenvironment of the p53R172H tumors. These findings sustain a potential role for p53 profiling in personalized oral cancer immunoprevention.

6090 Background: ACC is a common salivary gland malignancy for which there is no FDA approved therapies. Despite a quiet genome, ACC has significant tumoral heterogeneity, which may facilitate the metastatic relapse. Studies focusing on the deep profile of ACC tumor microenvironment (TME) are lacking. Here we explored the TME of ACC using imaging mass cytometry (IMC) and assessed TME attributes and its association with histology and clinical outcomes. Methods: Two tissue microarrays from 62 ACC patients (pts) were built and stained with 37 metal-tagged markers. IMC was performed with the Fluidigm Helios CyTOF instrument utilizing the Hyperion Imaging System Laser ablation. Tissue and cell segmentation and multiplex imaging analysis were performed with Visiopharm software using pre-trained artificial intelligence algorithms. Comparison of cell types and markers densities among histology sub-groups were analyzed with Wilcoxon signed-rank test and its association with overall survival (OS) with log-rank and Cox Proportional Hazards. Results: Of 62 pts, 37% (23/62) had solid histology, 19% (12/62) were metastatic at diagnosis, and 55% (30/54) had disease recurrence during follow-up. With a median follow-up of 7.9 y, the median OS was 9.3y (CI 95%, 7.8-NR). Pts with solid subtype had poorer OS than non-solid histology (5.2 vs 14.6 y, p = 0.004). The IMC final dataset comprised 507,524 single-cells. No significant differences were found in cell subpopulations density between solid and non-solid histology. The most represented cell population in the stroma were macrophages, followed by CD8+ T cells, and fibroblasts. A higher percentage of M2-macrophage was associated with poor survival (p = 0.001), whereas, a higher percentage of M1-macrophage (M1:M2 ratio) was associated with better prognosis. No other immune cell type, fibroblasts or immune cell functional markers (TIGIT, TIM3, granzyme B, and PD-L1) correlated with survival. Regarding tumor markers, a higher expression of BCL-2, B7-H4, and Ki67 in the tumor cells were associated with worst survival; and remained statistically associated after adjustment for histology and staging (all p < 0.001). Solid histology had a significantly higher density of tumor cells expressing B7-H4, BCL-2, and Ki67 compared to cribriform and tubular histology. A higher expression of myoepithelial marker (p63+) were associated with a better survival when compared with tumors with low p63 expression. Conclusions: ACC’s TME is composed mainly of macrophages. Despite having no significant differences in cellular composition, a higher density of tumor cells expressing BCL-2, B7-H4 and Ki67 were found in the solid histology and these markers were independent predictors of poor prognosis. The overexpression of BCL-2 and B7-H4 in the solid histology provides a scientific rationale for BCL-2 and/or B7-H4 targeting for the most aggressive ACC.

Purpose: Salivary gland carcinomas (SGCs) are pathologically classified into several widely diverse subtypes, of which adenoid cystic carcinoma (ACC), mucoepidermoid carcinoma (MEC), and salivary duct carcinoma (SDC) are the most commonly encountered. A comparative genetic analysis of these subtypes provides detailed information on the genetic alterations that are associated with their tumorigenesis and may lead to the identification of biomarkers to guide tumor-specific clinical trials. Experimental Design: Whole-genome sequencing of 58 common SGCs (20 ACCs, 20 SDCs, and 18 MECs) was performed to catalog structural variations, copy number, rearrangements, and driver mutations. Data were bioinformatically analyzed and correlated with clinicopathologic parameters, and selected targets were validated. Results: Novel and recurrent type–specific and shared genetic alterations were identified within and among 3 subtypes. Mutually exclusive canonical fusion and nonfusion genomic alterations were identified in both ACC and MEC. In ACCs, loss of chromosome 12q was dominant in MYB or MYBL1 fusion–positive tumors and mutations of NOTCH pathway were more common in these fusion negatives. In MECs, CRTC1-MAML2 fusion–positive tumors showed frequent BAP1 mutation, and tumors lacking this fusion were enriched with LRFN1 mutation. SDCs displayed considerable genetic instability, lacked recurrent chromosomal rearrangements, and demonstrated nonoverlapping TP53 mutation and ERBB2 amplification in a subset of tumors. Limited genetic alterations, including focal amplifications of 8q21-q23, were shared by all subtypes and were associated with poor survival. Conclusions: This study delineates type-specific and shared genetic alterations that are associated with early phenotypic commitment and the biologic progression of common SGCs. These alterations, upon validation, could serve as biomarkers in tumor-specific clinical trials.

Acinic cell carcinoma (AcCC) is a morphologically distinctive salivary gland malignancy often associated with chromosome rearrangements leading to overexpression of the NR4A3 transcription factor. However, little is known about how NR4A3 contributes to AcCC biology. Detailed RNA-sequencing of 21 archived AcCC samples revealed fusion reads arising from recurrent t(4, 9), t(9, 12), t(8, 9) or t(2, 4) chromosomal translocations, which positioned highly active enhancers adjacent to the promoter of the NR4A3 gene or the closely related NR4A2 gene, resulting in their aberrant overexpression. Transcriptome analyses revealed several distinct subgroups of AcCC tumors, including a subgroup that overexpressed both NR4A3 and MSANTD3. A poor survival subset of the tumors with high-grade transformation expressed NR4A3 and POMC as well as MYB, an oncogene that is the major driver in a different type of salivary gland tumor, adenoid cystic carcinoma. The combination of NR4A3 and MYB showed cooperativity in regulating a distinct set of genes. In addition, the ligand binding domain of NR4A3 directly bound the Myb DNA binding domain. Transformation assays indicated that, while overexpressed NR4A3 was sufficient to generate transformed colonies, the combination of NR4A3 plus Myb was more potent, leading to anchorage-independent growth and increased cellular invasiveness. The results confirm that NR4A3 and NR4A2 are the main driver genes of AcCC and suggest that concurrent overexpression of NR4A3 and MYB defines a subset of AcCC patients with high-grade transformation that display exceptionally poor outcome.

Background Patients with advanced primary and recurrent salivary duct carcinoma (SDC), a rare and lethal malignancy, have limited therapeutic options. Novel small-molecule agents aimed at targeting critical signaling associated with SDC tumorigenesis may lead to new therapeutic options for patients with these tumors. The human epidermal growth factor receptor 2 (HER2)/phosphoinositide 3-kinase (PI3K) axis, an important oncogenic pathway, has been targeted for therapy in several solid tumors. Currently, little is known about the role and clinical implications of alterations of the HER2/PI3K pathway in patients with SDC. Methods The authors investigated the clinicopathologic features, genetic alterations, and expression of key members of the HER2/PI3K pathway in 43 primary tumors and conducted in vitro functional and targeted drug-response analyses on cell lines derived from salivary epithelial carcinomas. Results In primary tumors, loss of phosphatase and tensin homolog (PTEN) expression was identified in 22 of 43 tumors (51%), overexpression of HER2 was observed in 12 of 43 tumors (28%), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutations were identified in 12 of 43 tumors (28%). Phosphorylated protein kinase B (p-AKT) was highly expressed in most tumors. Most tumors (70%) displayed mutually exclusive alterations of PI3K members, whereas 8 tumors (19%) had 2 or more concurrent abnormalities. In vitro studies demonstrated a direct association between PTEN loss and PI3K pathway activation and evidence of response to combined PI3Kα and PI3Kβ and/or pan-PI3K inhibitors. Conclusions The current analyses reveal frequent PTEN loss and mutually exclusive alterations of key PI3K pathway members in SDC and demonstrate in vitro evidence of a response to pan-PI3K inhibitors. These results provide a framework for a biomarker-based substratification of patients with SDC in future targeted therapy. Cancer 2018;124:3523-32. © 2018 American Cancer Society.

TP53 mutations are the most frequent genetic alterations in breast cancer and are associated with more aggressive disease and worse overall survival. We have created two conditional mutant Trp53 alleles in the mouse that allow expression of Trp53R172H or Trp53R245W missense mutations in single cells surrounded by a normal stroma and immune system. Mice with Trp53 mutations in a few breast epithelial cells develop breast cancers with high similarity to human breast cancer including triple negative. p53R245W tumors are the most aggressive and exhibit metastases to lung and liver. Development of p53R172H breast tumors with some metastases requires additional hits. Sequencing of primary tumors and metastases shows p53R245W drives a parallel evolutionary pattern of metastases. These in vivo models most closely simulate the genesis of human breast cancer and will thus be invaluable in testing novel therapeutic options., Mutations in TP53 gene are very common in cancer development. Here the authors take advantage of murine models to show that somatic Trp53 mutations differentially drive breast cancer and evolution of metastases.

Objectives To investigate the impact of 3-Diminsional (3D) tumor volume (TV) and extent of involvement of primary tumor on treatment outcomes in a large uniform cohort of T3 laryngeal carcinoma patients treated with nonsurgical laryngeal preservation strategies. Materials and Methods The pretreatment contrast-enhanced computed tomography images of 90 patients with T3 laryngeal carcinoma were reviewed. Primary gross tumor volume (GTVp) was delineated to calculate the 3D TV and define the extent of invasion. Cartilage and soft tissue involvement was coded. The extent of invasion was dichotomized into non/limited invasion versus multiple invasion extension (MIE), and was subsequently correlated with survival outcomes. Results The median TV was 6.6 cm3. Sixty-five patients had non/limited invasion, and 25 had MIE. Median follow-up for surviving patients was 52 months. The 5-year local control and overall survival rates for the whole cohort were 88% and 68%, respectively. There was no correlation between TV and survival outcomes. However, patients with non/limited invasion had better 5-year local control (LC) than those with MIE (95% vs 72%, p = .009) but did not have a significantly higher rate of overall survival (OS) (74% vs 67%, p = .327). In multivariate correlates of LC, MIE maintained statistical significance whereas baseline airway status showed a statistically significance trend with poor LC (p = .0087 and 0.06, respectively). Baseline good performance status was an independent predictor of improved OS (p = .03) in multivariate analysis. Conclusion The extent of primary tumor invasion is an independent prognostic factor of LC of the disease after definitive radiotherapy in T3 larynx cancer.

TP53 mutations occur in ∼50% of all human tumors, with increased frequency in aggressive cancers that are notoriously difficult to treat. Additionally, p53 missense mutations are remarkably predictive of refractoriness to chemo/radiotherapy in various malignancies. These observations have led to the development of mutant p53-targeting agents that restore p53 function. An important unknown is which p53-mutant tumors will respond to p53 reactivation-based therapies. Here, we found a heterogeneous impact on therapeutic response to p53 restoration, suggesting that it will unlikely be effective as a monotherapy. Through gene expression profiling of p53 R172H -mutant lymphomas, we identified retinoic acid receptor gamma (RARγ) as an actionable target and demonstrated that pharmacological activation of RARγ with a synthetic retinoid sensitizes resistant p53-mutant lymphomas to p53 restoration, while additively improving outcome and survival in inherently sensitive tumors.

The solid tumor microenvironment includes nerve fibers that arise from the peripheral nervous system. Recent work indicates that newly formed adrenergic nerve fibers promote tumor growth, but the origin of these nerves and the mechanism of their inception are unknown. Here, by comparing the transcriptomes of cancer-associated trigeminal sensory neurons with those of endogenous neurons in multiple mouse models of oral cancer, we identified an adrenergic differentiation signature. We show that loss of TP53 leads to adrenergic transdifferentiation of tumor-associated sensory nerves through loss of the microRNA miR-34a. Tumor cells that expressed wild-type p53 protein released vesicles containing microRNAs that were taken up by neighboring neurons. MiR-34a blocks neuronal proliferation, and the neurons were maintained in their current state. By contrast, tumors that had a mutant versions of the gene encoding p53 released vesicles that lacked miR-34a. In this case, neurons increased in number in the vicinity of the tumor, and these cells were reprogrammed as adrenergic neurons that express the molecule noradrenaline. These neurons had more axonal branches than did those near tumors that expressed wild-type p53. Interactions between adrenergic neurons and the tumor aided cancer growth. Tumor growth was inhibited by sensory denervation or pharmacological blockade of adrenergic receptors, but not by chemical sympathectomy of pre-existing adrenergic nerves; and when mice received a transplant of p53-deficient tumor cells, treatment with a drug (carvedilol) that blocks adrenergic signaling pathways slowed tumor growth. A retrospective analysis of tumor samples from patients with oral cancer revealed that p53 status was associated with nerve density, which was in turn associated with poor clinical outcomes. Neural regulation represents an emerging targetable pathway for the treatment of cancer. The peripheral adrenergic nervous system has previously been shown to regulate cancer tumorigenesis. In contrast to previous findings using a prostate cancer mouse model, in our oral cancer mouse model, ablation of the sympathetic nervous system before tumor inoculation neither abrogated the development of adrenergic neo-nerves nor inhibited tumor growth. Our present study reveals that the emergence of adrenergic neonerves in the tumor microenvironment accompanies the initial phase of oral cavity squamous cell carcinoma (OCSCC) development in a transgenic OCSCC mouse models. We have identified crosstalk between the peripheral nervous system and head and neck tumors and described a phenotypic switch, induced by cancer cells, in which sensory nerves differentiate into adrenergic neo-neurons. This crosstalk between cancer cells and neurons represents mechanism by which tumor-associated neurons are reprogrammed towards an adrenergic phenotype that can stimulate tumor progression, and is a potential target for anticancer therapy. Our findings show that in p53-deficient tumors, an miRNA-based mechanism mediates neuronal responses to environmental cues and determines the fate of cancer-associated neurons. We have shown that axonal sprouting and autonomic reprogramming of existing nerves occur as a result of exosomal miRNA shuttling from cancer cells to neurons. These miRNAs orchestrate gene expression via combined dominantly negative (for example, miR-34a) and positive (for example, miR-21 and miR-324) effects, activating transcriptional programs that establish neuronal identity. In our mouse model of OCSCC, surgical ablation of sensory nerves prevented the development of these adrenergic neo-nerves; and as tumors evolve, neo-neural networks develop in and around the tumor stroma, providing signals that coordinate cancer progression. Our results thus show that the peripheral sensory nerves may be reprogrammed during the development of cancer in a manner similar to that of neural progenitors that initiate adrenergic neurogenesis during tumor formation. These results are consistent with recent preclinical data suggesting that sympathetic fibers accumulate in the normal vicinity of solid tumor tissues and infiltrate into the stroma. Furthermore, clinical data show that cancer patients treated with β-blockade have improved survival, supporting the role of adrenergic nerve activity in cancer progression. Although further studies will be required to dissect the molecular events that link tumor-associated neuritogenesis to cancer progression, our data raise the tantalizing possibility that drugs that target both axonal growth and the adrenergic nervous system could be useful for the treatment of cancer. Moreover, our discovery that the absence of functional p53 influences the formation of neighboring neurons might have relevance for interpreting reports showing that fluctuations in the levels of wild-type p53 are observed in nerve regeneration. Thus, these findings might have repercussions that reach beyond the field of cancer research to regenerative medicine. Citation Format: Moran Amit, Hideaki Takahashi, Mihnea-Paul Dragomir, Simone Anfossi, Antje Lindemann, Frederico Netto-Glebber, Samantha Tam, Abdullah Osman, Erik Kuntsen, Curtis R. Pickering, Mei Zhao, Xiayu Rao, Jing Wang, Deborah A. Silverman, Carlos Caulin, Assaf Zinger, Ennio Tasciotti, Patrick Dougherty, Adel El-Naggar, George A. Calin, Jeffrey N. Myers. Cancer takes a nerve: Loss of p53 drives neuron reprogramming in head and neck cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr NG07.

We have previously shown that gene expression profiles of oral leukoplakia (OL) may improve the prediction of oral cancer (OC) risk. To identify new targets for prevention, we performed a systematic survey of transcripts associated with an increased risk of oral cancer and overexpressed in OC vs normal mucosa (NM).We used gene expression profiles of 86 patients with OL and available outcomes from a chemoprevention trial of OC and NM. MET expression was evaluated using immunohistochemistry in 120 OL patients, and its association with OC development was tested in multivariable analysis. Sensitivity to pharmacological Met inhibition was tested invitro in premalignant and OC cell lines (n = 33) and invivo using the 4-NQO model of oral chemoprevention (n = 20 mice per group). All statistical tests were two-sided.The overlap of 693 transcripts associated with an increased risk of OC with 163 transcripts overexpressed in OC compared with NM led to the identification of 23 overlapping transcripts, including MET. MET overexpression in OL was associated with a hazard ratio of 3.84 (95% confidence interval = 1.59 to 9.27, P = .003) of developing OC. Met activation was found in OC and preneoplastic cell lines. Crizotinib activity in preneoplastic and OC cell lines was comparable. ARQ 197 was more active in preneoplastic compared with OC cell lines. In the 4-NQO model, squamous cell carcinoma, dysplasia, and hyperkeratosis were observed in 75.0%, 15.0%, and 10.0% in the control group, and in 25.0%, 70.0%, and 5.0% in the crizotinib group (P.001).Together, these data suggest that MET activation may represent an early driver in oral premalignancy and a target for chemoprevention of OC.

MDM2, an E3 ubiquitin ligase, is a potent inhibitor of the p53 tumor suppressor and is elevated in many human cancers that retain wild-type p53. MDM2 SNP309G is a functional polymorphism that results in elevated levels of MDM2 (due to enhanced SP1 binding to the MDM2 promoter) thus decreasing p53 activity. Mdm2SNP309G/G mice are more prone to spontaneous tumor formation than Mdm2SNP309T/T mice, providing direct evidence for the impact of this SNP in tumor development. We asked whether environmental factors impact SNP309G function and show that SNP309G cooperates with ionizing radiation to exacerbate tumor development. Surprisingly, ultraviolet B light or Benzo(a)pyrene exposure of skin shows that SNP309G allele actually protects against squamous cell carcinoma susceptibility. These contrasting differences led us to interrogate the mechanism by which Mdm2 SNP309 regulates tumor susceptibility in a tissue-specific manner. Although basal Mdm2 levels were significantly higher in most tissues in Mdm2SNP309G/G mice compared with Mdm2SNP309T/T mice, they were significantly lower in Mdm2SNP309G/G keratinocytes, the cell-type susceptible to squamous cell carcinoma. The assessment of potential transcriptional regulators in ENCODE ChIP-seq database identified transcriptional repressor E2F6 as a possible negative regulator of MDM2 expression. Our data show that E2F6 suppresses Mdm2 expression in cells harboring the SNP309G allele but not the SNP309T allele. Thus, Mdm2 SNP309G exhibits tissue-specific regulation and differentially impacts cancer risk.

Objectives To develop and characterize in vitro salivary duct carcinoma as a surrogate for functional studies. Materials and methods Cells were dispersed from tumor tissue fragments under sterile conditions in RPMI media. Disassociated cells were cultivated, immortalized with hTERT and propagated for more than 100 passages. Morphologic, linage, cytogenetic and genomic analyses were performed on different passages of cell line and primary tumor. Soft agar growth was performed. Results Analysis of cytomorphologic features, growth characteristics and lineage specific markers expression confirmed the epithelial derivation and the neoplastic nature of the cell line. DNA STRs analysis showed identical match of both cell line and primary tumor. Cultivated cells expressed Androgen Receptor (AR), PTEN, and EFGR proteins and the AR-V7 isoform transcript. Comparative exome-sequencing identified common mutated genes in both cell line and primary tumor. In-vitro colony formation of late passages is established. Conclusion We report the development of the first human salivary duct carcinoma cell line (MDA-SDC-04) that retains critical biological and genomic features of the donor tumor.

Amphetamine-associated CNS vasculitis is controversial. There are few reports but none as a tumor mimic to our knowledge. We describe a pathology-proven, amphetamine-associated CNS vasculitis resembling a tumor. A 41-year-old man presented with six weeks of progressive confusion and left-sided weakness. CT head reported a right thalamic mass with vasogenic edema. Laboratory tests were unremarkable except for cannabinoids and amphetamine in urine. MRI brain showed enhancement in right frontotemporal lobe, basal ganglia, and thalamus concerning for glioblastoma multiforme. After high-dose IV dexamethasone, an initial biopsy showed reactive gliosis, perivascular lymphocytic cuffing by CD3+, rare CD20+ cells and no infection. He continued to decline. MRI 22 days after admission showed increased T2/FLAIR hyperintensity, multifocal areas of enhancement, microhemorrhages, and ischemia. High-grade glioma, lymphoma and infectious encephalitis remained on differentials. Treatment included broad-spectrum antibiotics and acyclovir. Biopsy on 23rd day showed reactive gliosis with parenchymal macrophage infiltration and perivascular cuffing with mixed inflammatory infiltrates. CSF: slightly elevated WBCs (8/µL), elevated protein (139mg/dL), normal glucose, and no infection. MRI whole spine and CT body were unremarkable. The patient was transferred to MDACC 5.5 weeks after initial presentation. He was alert with expressive aphasia, right gaze preference, left hemiplegia, and right hemiparesis. He underwent a right anterior temporal lobectomy. Pathology showed extensive cortical laminar and white matter necrosis with macrophage infiltration and microglial activation. In areas of the preserved cortex, vasculocentric lymphocytic aggregates were present and reticulin staining showed lymphocytic infiltration of the vascular walls. Immunophenotyping (CD3, CD20) showed an almost pure T-cell population. The predominance of intramural T-lymphocytes reflected a vasculitic process. The final diagnosis was cerebral vasculitis with subacute infarction. The patient died six days later. The autopsy findings were identical to the previous resection without evidence of systemic inflammation.

BACKGROUND: Adenoid cystic carcinoma (ACC) is a rare malignancy arising in salivary glands and other sites, characterized by high rates of relapse and distant spread. Recurrent/metastatic (R/M) ACCs are generally incurable, due to a lack of active systemic therapies. To improve outcomes, deeper understanding of genetic alterations and vulnerabilities in R/M tumors is needed. METHODS: An integrated genomic analysis of 1,045 ACCs (177 primary, 868 R/M) was performed to identify alterations associated with advanced and metastatic tumors. Intratumoral genetic heterogeneity, germline mutations, and therapeutic actionability were assessed. RESULTS: Compared with primary tumors, R/M tumors were enriched for alterations in key Notch (NOTCH1, 26.3% vs. 8.5%; NOTCH2, 4.6% vs. 2.3%; NOTCH3, 5.7% vs. 2.3%; NOTCH4, 3.6% vs. 0.6%) and chromatin-remodeling (KDM6A, 15.2% vs. 3.4%; KMT2C/MLL3, 14.3% vs. 4.0%; ARID1B, 14.1% vs. 4.0%) genes. TERT promoter mutations (13.1% of R/M cases) were mutually exclusive with both NOTCH1 mutations (q = 3.3 × 10(–4)) and MYB/MYBL1 fusions (q = 5.6 × 10(–3)), suggesting discrete, alternative mechanisms of tumorigenesis. This network of alterations defined 4 distinct ACC subgroups: MYB(+)NOTCH1(+), MYB(+)/other, MYB(WT)NOTCH1(+), and MYB(WT)TERT(+). Despite low mutational load, we identified numerous samples with marked intratumoral genetic heterogeneity, including branching evolution across multiregion sequencing. CONCLUSION: These observations collectively redefine the molecular underpinnings of ACC progression and identify further targets for precision therapies. FUNDING: Adenoid Cystic Carcinoma Research Foundation, Pershing Square Sohn Cancer Research grant, the PaineWebber Chair, Stand Up 2 Cancer, NIH R01 CA205426, the STARR Cancer Consortium, NCI R35 CA232097, the Frederick Adler Chair, Cycle for Survival, the Jayme Flowers Fund, The Sebastian Nativo Fund, NIH K08 DE024774 and R01 DE027738, and MSKCC through NIH/NCI Cancer Center Support Grant (P30 CA008748).

Dicer1 functions as a tumor suppressor in mouse models. In humans, somatic mutations are associated with many cancers in adults, and patients with DICER1 syndrome with DICER1 germline mutations are susceptible to childhood cancers. Dicer is phosphorylated by the ERK-MAP kinase pathway and because this pathway is activated in human cancers, we asked whether phosphorylated Dicer1 contributed to tumor development. In human endometrioid cancers, we discovered that phosphorylated DICER1 is significantly associated with invasive disease. To test a direct involvement of Dicer1 phosphorylation in tumor development, we studied mice with phosphomimetic alterations at the two conserved serines phosphorylated by ERK and discovered that a phosphomimetic Dicer1 drives tumor development and dissemination in two independent murine cancer models (KRas+/LA1 and p53+/−). Our findings demonstrate that phosphomimetic Dicer1 promotes tumor development and invasion. Significance: This work highlights the relevance of Dicer1 phosphorylation in mammalian tumor development and dissemination.

6014 Background: Chemoradiation (CRT) with cis or anti-EGFR Ab has been shown to improve survival of patients with stage III-IV HNC. Since Lap, a dual EGFR and HER2 inhibitor, has shown effectiveness with CRT in a pilot non-HPV HNC cohort, the RTOG Foundation launched a phase II trial to test the hypothesis that adding Lap to the RT-cis for frontline therapy of stage III-IV Non-HPV HNC improves progression-free survival (PFS). Methods: Patients with stage III-IV carcinoma of the oropharynx (p16-negative), larynx, and hypopharynx, having Zubrod performance of 0-1, and meeting predefined blood chemistry criteria were enrolled after providing consent. Patients were randomized (1:1) to 70 Gy (6 weeks) + 2 cycles of CDDP (q3 weeks) plus either Lap (1500 mg daily, Arm A) or placebo (Arm B) starting 1 week prior to RT and concurrent with RT and for 3 months post RT. PFS was the primary endpoint. The protocol specified 69 PFS events (142 patients) for the final analysis based on HR = 0.65, 80% power, 1-sided alpha 0.20, and one interim efficacy and futility analysis at 50% information. PFS rates between arms for all randomized patients were compared by 1-sided log-rank test (1-sided alpha 0.1803). Overall survival (OS) was a secondary endpoint. Results: From 10/’12 to 04/’17, 142 patients were enrolled, of whom 127 were randomized, 63 to Arm A and 64 to Arm B. Arms A vs B, respectively, were similar in baseline patient characteristics, radiation delivery, completing ≥ 70 Gy (85.7% vs. 82.8%) and cisplatin delivery, completing 200 (±5%) mg/m2 (65.1% vs 70.3%), but dissimilar in Lap/placebo delivery (median dose, 87000 mg vs. 125250 mg). Median follow-up was 4.1 years for surviving patients. The final analysis suggests no improvement in PFS of adding Lap to CRT (HR [A/B]: 0.91, 95% confidence interval CI 0.56-1.46; P= 0.34; 2-year rates: 50.6%, CI 37.5-63.7% vs. 56.2% CI 43.0-69.4%), or in OS (HR: 1.06, CI 0.61-1.86; P = 0.58; 2-year rates: 71.8% CI 60.1-83.5% vs. 76% CI 64.5-87.4%), death within 30 days of therapy (3.3% vs. 3.4%), and overall treatment-related grade 3-5 adverse event rate (86.7% vs. 84.7%). Grade 3-4 mucositis rates on Arm A and Arm B were 21.7% vs. 23.7%, all grade dysphagia and rash rates were 43.3% vs. 59.3%, and 13.3% vs. 6.8%, respectively. Conclusions: The addition of Lap to the radiation-cisplatin platform did not improve progression-free or overall survival in unselected non-HPV HN. Thus, dual EGFR, HER-2 inhibition does not appear to enhance the effects of chemoradiation. Although we showed that accrual to a non-HPV HN specific trial is feasible, new strategies must be investigated to improve the outcome for this poor prognosis HN population.

6084 Background: Salivary duct carcinoma (SDC) and adenocarcinoma, not otherwise specified (Adeno-NOS) are rare and aggressive subtypes of salivary gland cancers. Biomarker studies revealed targetable alterations such as androgen receptor (AR) and HER2 overexpression; nevertheless, chemotherapy (CT) remains the cornerstone treatment of patients (pts) with locally advanced or metastatic disease based on limited efficacy data. We sought to describe the treatment patterns and outcomes of SDC and Adeno-NOS pts. Methods: We retrospectively collected clinicopathological, treatment, and outcomes data of SDC or Adeno-NOS pts that were seen at MD Anderson from 1990-2020. AR positivity was defined by IHC staining in ≥ 10% of tumor cells, and HER2 by IHC 2+ or 3+ scores. Overall response rate (ORR) was assessed by an independent radiologist per RECIST v1.1. Recurrence-free survival (RFS) and overall survival (OS) from diagnosis were estimated using log-rank test. A multivariable cox regression model was performed to estimate the hazard-ratio (HR) of risk factors on pts outcomes. Results: 200 pts were included, 110 had SDC and 90 Adeno-NOS. Most pts (61%) presented with locoregional disease (stage III-IVB), while 13% had distant metastasis (IVC). AR was positive in 77% of cases, and HER2 in 47%. In the curative setting (N=174), 98% pts underwent surgery and 90% radiotherapy (RT); 15 pts with stage IVA-B disease had aggressive trimodality therapy including surgery, RT, and systemic therapy. Overall, 55% pts recurred. The mRFS and 5-y RFS rate were 24 mos (95%CI, 16-43) and 34.5%, respectively. For pts with IV-A-B stage, trimodality therapy was associated with an improved OS in comparison to surgery and/or RT (39 mos vs NA, p=0.04). In the metastatic setting, 82 pts received ≥1 line of systemic therapy; the preferred 1st line regimen was platinum/taxane with or without trastuzumab (50%). Table summarizes the ORR and mPFS to each therapy line. ORR and PFS was higher for HER2-targeted therapy (1st line: 47% and 11 mos; 2nd line 29% and 6 mos; respectively); only 10 pts received androgen blockage. At a median follow-up of 7.5 y, the mOS was 5 ys and the 5-y OS rate was 50%. In multivariate analysis, higher T and N stages (HR 2.1 and 3.8, p

We present a proteogenomic study of 108 human papilloma virus (HPV)-negative head and neck squamous cell carcinomas (HNSCCs). Proteomic analysis systematically catalogs HNSCC-associated proteins and phosphosites, prioritizes copy number drivers, and highlights an oncogenic role for RNA processing genes. Proteomic investigation of mutual exclusivity between FAT1 truncating mutations and 11q13.3 amplifications reveals dysregulated actin dynamics as a common functional consequence. Phosphoproteomics characterizes two modes of EGFR activation, suggesting a new strategy to stratify HNSCCs based on EGFR ligand abundance for effective treatment with inhibitory EGFR monoclonal antibodies. Widespread deletion of immune modulatory genes accounts for low immune infiltration in immune-cold tumors, whereas concordant upregulation of multiple immune checkpoint proteins may underlie resistance to anti-programmed cell death protein 1 monotherapy in immune-hot tumors. Multi-omic analysis identifies three molecular subtypes with high potential for treatment with CDK inhibitors, anti-EGFR antibody therapy, and immunotherapy, respectively. Altogether, proteogenomics provides a systematic framework to inform HNSCC biology and treatment.

The phosphatidylinositol 3′ kinase (PI3K)/phosphatase and tensin homologue deleted on chromosome ten/Akt pathway, which is a critical regulator of cell proliferation and survival, is mutated or activated in a wide variety of cancers. Akt appears to be a key central node in this pathway and thus is an attractive target for targeted molecular therapy. We demonstrated that Akt is highly phosphorylated in thyroid cancer cell lines and human thyroid cancer specimens, and hypothesised that KP372-1, an Akt inhibitor, would block signalling through the PI3K pathway and inhibit cell proliferation while inducing apoptosis of thyroid cancer cells. KP372-1 blocked signalling downstream of Akt in thyroid tumour cells, leading to inhibition of cell proliferation and increased apoptosis. As thyroid cancer consistently expresses phosphorylated Akt and KP372-1 effectively blocks Akt signalling, further preclinical evaluation of this compound for treatment of thyroid cancer is warranted.

p53 (TP53) is the most frequently mutated gene in squamous cell carcinomas (SCCs) of the skin and head and neck. Certain p53 mutations are oncogenic and promote invasion and metastasis in SCCs. However, it is unclear how the oncogenic function of mutant p53 is modulated by other molecular alterations that co-exist in SCCs. Here, we show that deletion of the p53 gene and activation of an endogenous p53(R172H) gain-of-function mutation in the skin induce carcinomas with similar kinetics and penetrance. Deletion of p53 induced primarily well-differentiated SCCs. However, most of the tumours induced by p53(R172H) were poorly differentiated SCCs, the only metastatic tumours in this model. These tumours expressed higher levels of cyclin D1 than the well-differentiated SCCs and spindle carcinomas that developed in these mice. Unexpectedly, metastasis was not observed in mice that developed spindle carcinomas, which expressed high levels of the tumour suppressors p16(Ink4a) and p19(Arf) , encoded by Cdkn2a, a gene frequently deleted in human SCCs. Remarkably, deletion of the Cdkn2a gene in p53(R172H) -induced SCCs promoted a dramatic increase in metastasis rates and a shorter survival in mice that developed these tumours, compared with those observed in mice with tumours in which Cdkn2a was deleted in the presence of a p53 loss-of-function mutation or wild-type p53. Accordingly, the survival of patients with head and neck SCCs bearing co-occurring high-risk p53 mutations and CDKN2A homozygous deletions was much shorter than that of patients with tumours in which high-risk p53 mutations did not contain CDKN2A homozygous deletions, or that of patients with tumours in which homozygous CDKN2A deletions co-existed with either low-risk p53 mutations or potential loss-of-function mutations in p53. These findings genetically identify a population of SCC patients with worst outcomes and will help to predict outcomes according to the p53 status and alterations in CDKN2A. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Purpose: Head and neck squamous cell carcinoma (HNSCC) is commonly treated with radiotherapy, and local failure after treatment remains the major cause of disease-related mortality. To date, human papillomavirus (HPV) is the only known clinically validated, targetable biomarkers of response to radiation in HNSCC. Experimental Design: We performed proteomic and transcriptomic analysis of targetable biomarkers of radioresistance in HPV-negative HNSCC cell lines in vitro, and tested whether pharmacologic blockade of candidate biomarkers sensitized cells to radiotherapy. Candidate biomarkers were then investigated in several independent cohorts of patients with HNSCC. Results: Increased expression of several targets was associated with radioresistance, including FGFR, ERK1, EGFR, and focal adhesion kinase (FAK), also known as PTK2. Chemical inhibition of PTK2/FAK, but not FGFR, led to significant radiosensitization with increased G2–M arrest and potentiated DNA damage. PTK2/FAK overexpression was associated with gene amplification in HPV-negative HNSCC cell lines and clinical tumors. In two independent cohorts of patients with locally advanced HPV-negative HNSCC, PTK2/FAK amplification was highly associated with poorer disease-free survival (DFS; P = 0.012 and 0.034). PTK2/FAK mRNA expression was also associated with worse DFS (P = 0.03). Moreover, both PTK2/FAK mRNA (P = 0.021) and copy number (P = 0.063) were associated with DFS in the Head and Neck Cancer subgroup of The Cancer Genome Atlas. Conclusions: Proteomic analysis identified PTK2/FAK overexpression is a biomarker of radioresistance in locally advanced HNSCC, and PTK2/FAK inhibition radiosensitized HNSCC cells. Combinations of PTK2/FAK inhibition with radiotherapy merit further evaluation as a therapeutic strategy for improving local control in HPV-negative HNSCC. Clin Cancer Res; 22(18); 4643–50. ©2016 AACR.

Purpose To review our 15-year institutional experience using intensity modulated radiation therapy (IMRT) to reirradiate patients with head and neck squamous cell carcinomas (HNSCC) and identify predictors of outcomes and toxicity. Methods and Materials We retrospectively reviewed the records of 227 patients who received head and neck reirradiation using IMRT from 1999 to 2014. Patients treated with noncurative intent were excluded. Radiation-related acute and late toxicities were recorded. Prognostic variables included performance status, disease site, disease-free interval, chemotherapy, and RT dose and volume. Correlative analyses were performed separately for surgery and nonsurgery patients. Results Two hundred six patients (91%) were retreated with curative intent, and 173 had HNSCC histology; 104 (50%) underwent salvage resection, and 135 (66%) received chemotherapy. Median follow-up after reirradiation was 24.7 months. Clinical outcomes were worse for HNSCC patients, with 5-year locoregional control, progression-free survival, and overall survival rates of 53%, 22%, and 32%, respectively, compared with 74%, 59%, and 79%, respectively, for non-HNSCC patients. On multivariate analysis, concurrent chemotherapy and retreatment site were associated with tumor control, whereas performance status was associated with survival. Favorable prognostic factors specific to surgery patients were neck retreatment and lack of extracapsular extension, whereas for nonsurgery patients, these were a nasopharynx subsite and complete response to induction chemotherapy. Actuarial rates of grade ≥3 toxicity were 32% at 2 years and 48% at 5 years, with dysphagia or odynophagia being most common. Increased grade ≥3 toxicity was associated with retreatment volume >50 cm 3 and concurrent chemotherapy. Conclusions Reirradiation with IMRT either definitively or after salvage surgery can produce promising local control and survival in selected patients with head and neck cancers. Treatment-related toxicity remains significant. Prognostic factors are emerging to guide multidisciplinary treatment approaches and clinical trial design.

Translocation events are frequent in cancer and may create chimeric fusions or ‘regulatory rearrangements’ that drive oncogene overexpression. Here we identify super-enhancer translocations that drive overexpression of the oncogenic transcription factor MYB as a recurrent theme in adenoid cystic carcinoma (ACC). Whole-genome sequencing data and chromatin maps reveal distinct chromosomal rearrangements that juxtapose super-enhancers to the MYB locus. Chromosome conformation capture confirms that the translocated enhancers interact with the MYB promoter. Remarkably, MYB protein binds to the translocated enhancers, creating a positive feedback loop that sustains its expression. MYB also binds enhancers that drive different regulatory programs in alternate cell lineages in ACC, cooperating with TP63 in myoepithelial cells and a Notch program in luminal epithelial cells. Bromodomain inhibitors slow tumor growth in ACC primagraft models in vivo. Thus, our study identifies super-enhancer translocations that drive MYB expression and provides insight into downstream MYB functions in the alternate ACC lineages.

Simple Summary Cytopathology cannot distinguish benign from malignant follicular lesions in 20–30% of cases. These indeterminate cases includes the so-called follicular neoplasms (FNs) according to The Bethesda System for Reporting Thyroid Cytopathology. Frozen samples from 66 classic follicular adenomas (cFAs) and carcinomas (cFTCs) studied by array-comparative genomic hybridization identified three specific alterations of cFTCs (losses of 1p36.33-35.1 and 22q13.2-13.31, and gain of whole chromosome X) confirmed by fluorescent in situ hybridization (FISH) in a second independent series of 60 touch preparations from frozen samples of cFAs and cFTCs. In a third independent set of 27 cases of already stained pre-operative fine-needle aspiration cytology samples diagnosed as FNs and histologically verified, FISH analysis using these three markers identified half of cFTCs. Specificity of our assay for identifying cFTCs is higher than 98% which might be comparable with BRAF600E testing in cases of suspicion of classic papillary thyroid carcinomas. Abstract Although fine-needle aspiration cytology (FNAC) is helpful in determining whether thyroid nodules are benign or malignant, this distinction remains a cytological challenge in follicular neoplasms. Identification of genomic alterations in cytological specimens with direct and routine techniques would therefore have great clinical value. A series of 153 cases consisting of 72 and 81 histopathologically confirmed classic follicular adenomas (cFAs) and classic follicular thyroid carcinomas (cFTCs), respectively, was studied by means of different molecular techniques in three different cohorts of patients (pts). In the first cohort (training set) of 66 pts, three specific alterations characterized by array comparative genomic hybridization (aCGH) were exclusively found in half of cFTCs. These structural abnormalities corresponded to losses of 1p36.33-35.1 and 22q13.2-13.31, and gain of whole chromosome X. The second independent cohort (validation set) of 60 pts confirmed these data on touch preparations of frozen follicular neoplasms by triple DNA fluorescent in situ hybridization using selected commercially available probes. The third cohort, consisting of 27 archived cytological samples from an equal number of pts that had been obtained for preoperative FNAC and morphologically classified as and histologically verified to be follicular neoplasms, confirmed our previous findings and showed the feasibility of the DNA FISH (DNA fluorescent in situ hybridization) assay. All together, these data suggest that our triple DNA FISH diagnostic assay may detect 50% of cFTCs with a specificity higher than 98% and be useful as a low-cost adjunct to cytomorphology to help further classify follicular neoplasms on already routinely stained cytological specimens.

Adenoid cystic carcinoma (ACC) is the second most common malignancy of the salivary glands, also found at lower frequency rates in other secretory glands such as the mammary and lacrimal glands. Salivary ACCs are slow-growing but aggressive neoplasms, with propensity to perineural invasion and high recurrence rates. MYB is the most frequently altered gene in ACCs, as approximately 40% of the ACCs contain MYB-NFIB gene fusions, and the full-length MYB is overexpressed in over 50% of the fusion-negative ACCs. However, it is still unclear whether MYB activities promote ACC development. To assess the oncogenic potential of MYB in vivo, we generated transgenic mice that overexpress MYB using the TetO system. In these mice, focal MYB overexpression was directed to salivary and mammary glands using the activator line MMTV-tTA. We found that 25% of these mice developed tumors with an average latency of 23 months. Remarkably, all the tumors that developed in these mice were ACCs, and the three main phenotypic variants of human ACCs (cribriform, tubular and solid) were represented in this cohort. Using the same transgenic system, we found that the MYB-NFIB fusion also induced ACCs, with similar incidence and lower latency. Immunohistochemical analysis of these mouse ACCs for several biomarkers of human ACC, including p63 and c-kit, provided additional evidence of the similarity of the mouse ACCs that developed in these models, and human ACCs. RNAseq global expression profiling uncovered the activation of several cancer-associated pathways in MYB-induced mouse ACCs. Most notably, activation NOTCH signaling was highly enriched in these tumors. Additional analysis for the presence of the NOTCH intracellular domain demonstrated that all of the MYB- and MYB-NFIB-induced ACCs contain NOTCH activation. These findings, and the recent identification of activating mutations in NOTCH1 and NOTCH2 in human ACCs, suggest that NOTCH activities may contribute to ACC development. To test this hypothesis, ongoing studies in the lab are directed to assess the role of NOTCH signaling in ACC development, by generating mouse models in which constitutive activation of NOTCH is induced in mice alone or in combination with MYB alterations. Overall, these studies demonstrate that MYB activities are the main oncogenic driver of ACC. Genomic rearrangements that result in MYB-NFIB fusions may enhance the oncogenic potential of MYB. Citation Format: Yuan Hu, Xiaoyuan Zhu, Han Luo, Adel El-Naggar, Carlos Caulin. MYB and the MYB-NFIB fusion induce adenoid cystic carcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1611.

Immune checkpoint inhibitors such as anti-CTLA-4 (cytotoxic T-lymphocyte-associated protein 4), anti PD-1 (programmed cell death protein 1) and PD-L1 (programmed cell death protein-ligand 1) monoclonal antibodies are emerging as standard oncology treatments in various tumor types. The indications will expand as immunotherapies are being investigated in various tumors with promising results. Currently, there is inadequate identification of predictive biomarkers of response or toxicity. Unique response patterns include pseudoprogression and delayed response. The use of immune checkpoint inhibitors exhibit an unique toxicity profile, the immune-related adverse events (irAEs). The most notable immune reactions are noted in skin (rash), gastrointestinal track (colitis, hepatitis, pancreatitis), lung (pneumonitis), heart (myocarditis), and endocrine system (thyroiditis, hypophysitis). We present a patient with metastatic adenoid cystic carcinoma of the left submandibular gland with granulomatous inflammation of the lacrimal glands and axonal neuritis of the cervical and paraspinal nerves following treatment with ipilimumab and radiation therapy.

Background This study investigated the hypothesis that phosphoinositide 3-kinase (PI3-kinase) pathway dysregulation in either head and neck cancer cells and/or tumor infiltrating immune cells would influence outcomes of patients with surgically treated oral tongue squamous cell carcinomas (SCC). Methods We constructed tissue microarrays containing 123 oral tongue SCC samples and performed immunohistochemistry using antibodies against 7 PI3-kinase pathway markers: phosphatase and tensin homolog (PTEN), Akt, p-Akt, mammalian target of rapamycin (mTOR), phosphorylated-mammalian target of rapamycin (p-mTOR), survivin, and Ki-67). Expression levels in cancer cells or tumor infiltrating immune cells were correlated with outcomes. Results Higher levels of PTEN expression in immune cells were significantly associated with improved recurrence-free survival (heart rate (HR) = 0.45, 95% confidence interval (CI) 0.23-0.90, P = .03), and overall survival (HR = 0.34, 95% CI 0.15-0.76, P = .01) on univariate and multicovariate models. Conclusions We identified a novel, negative prognostic role of PI3-kinase activation (as determined by PTEN loss) in oral SCC infiltrating immune cells. These findings could be relevant for clinical development of PI-3 kinase inhibitors for this disease.

Summary Objectives The role of promoter methylation in the development of mucoepidermoid carcinoma (MEC) has not been fully explored. In this study, we investigated the epigenetic landscape of MEC. Methods The Illumina HumanMethylation27 BeadChip array and differential methylation analysis were utilized to screen for epigenetic alterations in 14 primary MEC tumors and 14 matched normal samples. Bisulfite sequencing was used to validate these results, with subsequent quantitative Methylation-Specific PCR (qMSP) to validate chloride intracellular channel protein 3 (CLIC3) in a separate cohort. Furthermore, CLIC3 immunohistochemical (IHC) staining was performed in another separate cohort of MEC. Finally, clinical and pathological characteristics were statistically analyzed for correlation with methylation status of CLIC3 and CLIC3 IHC H-scores by Wilcoxon rank sum, Kruskall–Wallis, and X2 test tests. Results We obtained 6 significantly differentially methylated gene candidates demonstrating significant promoter hyper- or hypo-methylation from the array data. Using bisulfite sequencing, we found one gene, CLIC3, which showed differential methylation between MEC tumor and normal samples in a small validation cohort. qMSP analysis of the CLIC3 promoter in a separate validation set showed significantly lower methylation level in tumor than in normal. The level of CLIC3 methylation in MECs was not statistically correlated with clinical or pathological characteristics. However, IHC staining intensity and distribution of CLIC3 were significantly increased in MECs, compared with those of normal salivary gland tissues. Conclusions Hypomethylation of CLIC3 promoter and its overexpression are significant events in MEC. Its functional role and potential therapeutic utility in MEC are worthy of further exploration.

Adenoid cystic carcinoma (ACC), a rare salivary gland malignancy, is a histogenetic, morphologic, and clinical heterogeneous disease. Extensive efforts have been made to characterize molecular events associated with these tumors, including the identification of prognostic and predictive biomarkers. Increased copy number gain and amplification of c-Met, the cell surface receptor for hepatocyte growth factor, has been shown to enhance tumor growth and invasiveness and promote metastasis in certain tumor types. In this study, we evaluated the expression of c-Met by immunohistochemistry (IHC) in a large cohort of salivary gland ACCs and examined its clinicopathologic implications. Archival formalin-fixed paraffin-embedded blocks from 200 ACC patients were used in this study. Pathologic patterns and phenotypic expression of c-Met were recorded and compared with clinical factors including gender, age, disease stage at diagnosis, and clinical outcomes. Correlations between c-MET expression and clinical characteristics were assessed by Pearson's chi-square test or by the 2-tailed Fisher exact test. Curves describing overall survival were generated by Kaplan-Meier product limit method. Strong c-MET expression was seen in inner ductal and outer myoepithelial cells in 53.2% of the cases. There was no correlation between c-Met overexpression and clinicopathologic parameters or patient's overall survival ( p = .94074). In conclusion, c-MET expression is high in a significant subgroup of ACC patients. While c-MET expression is not a prognostic factor in ACC, its role as a predictive marker of benefit from MET inhibitors deserves further investigation.

The aggressive role of TERT promoter mutations has been well established in differentiated thyroid cancer but has not been established in anaplastic thyroid cancer (ATC).We tested the mutation status by sequencing genomic tumor DNA and examined its relationship with clinicopathological characteristics of ATC.Among 106 American and Chinese ATC samples, TERT 1,295,228 CT (termed TERT C228T) mutation was found in 37 (34.9%) cases, TERT promoter mutation 1,295,250 CT was found in four cases (3.8%), and the two mutations were mutually exclusive and collectively found in 41 cases (38.7%). TERT C228T occurred in 28 of 90 (31.1%) wild-type BRAF cases vs nine of 16 (56.3%) BRAF V600E cases, with an odds ratio of 2.85 (95% confidence interval, 0.96-8.42; P = .05). Patient age was 67.6 ± 13.6 vs 61.6 ± 11.4 years in the TERT C228T vs wild-type TERT patients (P = .02), demonstrating an association between TERT C228T and older patient age. This association was also seen within the American cohort. In this cohort, which had more available clinicopathological data, TERT C228T was associated with distant metastasis of the tumor; specifically, distant metastasis occurred in 15 of 18 (83.3%) TERT C228T patients vs eight of 26 (30.8%) wild-type TERT patients, with an odds ratio of 11.25 (95% confidence interval, 2.53-50.08; P = .001). No association was found with patient sex, tumor size, lymph node metastasis, and extrathyroidal invasion of ATC.This is the largest study on the aggressive role of TERT promoter mutations in ATC, demonstrating an association of TERT C228T with BRAF V600E, older patient age, and tumor distant metastasis in ATC.

TP53 is the most frequently altered gene in head and neck squamous cell carcinoma (HNSCC), with mutations occurring in over two thirds of cases; however, the predictive response of these mutations to cisplatin-based therapy remains elusive. In the current study, we evaluate the ability of the Evolutionary Action score of TP53-coding variants (EAp53) to predict the impact of TP53 mutations on response to chemotherapy. The EAp53 approach clearly identifies a subset of high-risk TP53 mutations associated with decreased sensitivity to cisplatin both in vitro and in vivo in preclinical models of HNSCC. Furthermore, EAp53 can predict response to treatment and, more importantly, a survival benefit for a subset of head and neck cancer patients treated with platinum-based therapy. Prospective evaluation of this novel scoring system should enable more precise treatment selection for patients with HNSCC. Cancer Res; 75(7); 1205–15. ©2015 AACR.