Search

To examine trends and age-period-cohort effects (APC) on oral and pharyngeal cancers incidence in Singapore between 1968 and 2017 by human papillomavirus (HPV) status.All diagnosed oral and pharyngeal cancers and population size were extracted from the Singapore Cancer Registry and the Department of Statistics Singapore, respectively. Anatomical subsites were used as a proxy for HPV infection. Prais-Winsten regression assessed trends of age-standardised incidence rate (ASIR) (per 100,000 person-years); Poisson regression assessed APC effects on HPV-related and HPV-unrelated cancers.Over 50 years, 1,618 HPV-related and 2,977 HPV-unrelated oral and pharyngeal cancers were diagnosed, with the highest ASIR in Indians (6.93), followed by Chinese (2.81), and Malays (1.81). Overall, ASIR HPV-related cancers were stable while HPV-unrelated cancers decreased. The male-female ASIR ratio reduced from 5.82 (1968-1977) to 4.0 (2008-2017) for HPV-related cancers, and from 2.58 (1968-1977) to 1.52 (2008-2017) for HPV-unrelated cancers. HPV-unrelated ASIR in males decreased, but in females only among Indians. HPV-related ASIR decreased only among Indian females. The cohort born between 1983 and 1992 had the lowest incidence of HPV-related cancers in males but the highest in HPV-unrelated cancers. Period effect mainly contributed to HPV-related cancer among males with increased incidence after 1997. Overall, the age effect was more pronounced in males.HPV-related cancers accounted for 1/3 of oral and pharyngeal cancers. A significant decline was observed only for HPV-unrelated cancers. The cohort effect was mainly attributed to HPV-unrelated cancer incidence, while the period effect largely contributed to HPV-related cancer incidence, but only among males.

Thyroid nodules occur in about 60% of the population. A major challenge in thyroid nodule diagnosis is to distinguish between follicular adenoma (FA) and carcinoma (FTC). Here, we present a comprehensive thyroid spectral library covering five types of thyroid tissues. This library includes 121 960 peptides and 9941 protein groups. This spectral library can be used to quantify up to 7863 proteins from thyroid tissues, and can also be used to develop parallel reaction monitoring (PRM) assays for targeted protein quantification. Next, to stratify follicular thyroid tumours, we compared the proteomes of 24 FA and 22 FTC samples, and identified 204 differentially expressed proteins (DEPs). Our data suggest altered ferroptosis pathways in malignant follicular carcinoma. In all, 31 selected proteins effectively distinguished follicular tumours. Of those DEPs, nine proteins were further verified by PRM in an independent cohort of 18 FA and 19 FTC. Together, we present a comprehensive spectral library for DIA and targeted proteomics analysis of thyroid tissue specimens, and identified nine proteins that could potentially distinguish FA and FTC.

Despite revised staging criteria, stratification of patients with advanced oral squamous cell carcinoma (OSCC) remains difficult. Well-established features like perineural invasion (PNI), differentiation, and lymphovascular-invasion (LVI) are controversial, and hence omitted from staging. We endeavor to better stratify this cohort by identifying predictors of survival in advanced OSCC (T3-4).Seven hundred and forty-two patients with T3-4 OSCC underwent surgery from 2006 to 2013. Cox regression was performed to determine predictors of overall survival (OS).OS was adversely impacted by PNI (p = 0.046), LVI (p = 0.038), moderate/poor differentiation (p = 0.001), close/involved surgical margins (p = 0.002), pT (p = 0.034), and pN (p 0.001). The cumulative number of adverse histopathological features predicted poorer OS; HR 2.64 (CI 1.42-4.90) for one adverse feature and HR 4.23 (CI 2.34-7.67) for ≥2.In advanced OSCC, stratification with histopathologic risk factors can predict survival even in maximally treated patients; adjuvant therapies are unable to entirely mitigate this risk. Incorporation of adverse features into future editions of TNM can improve precision in staging and identify candidates for treatment escalation.

Background Patients with head and neck cancer have a higher risk of emergency department (ED) frequent attender (FA). We hypothesized that FAs present with issues different from non-FAs. Methods A retrospective cohort study was conducted on Singapore residents with head and neck cancers using de-identified registry merged with electronic medical record data. A competing risk regression analysis was performed to identify factors associated with FA. Aggregated primary diagnoses were compared for patients with and without FA risk factors. Results Thirteen percent of patients with head and neck cancer were FAs. FA risk factors were Charlson comorbidity index (3+), and socioeconomic status (SES). FAs had a higher proportion of respiratory infections. The spectrum of diagnosis was similar for patients with low and high SES. Current smokers had a greater proportion of respiratory complaints, relative to never smokers. Conclusion Patients with greater comorbidity scores or higher SES were more likely to be FA. FAs were more likely to present with respiratory complaints, likely related to cancer treatment, or smoking status.

Ameloblastoma is a rare tumor of odontogenic epithelium, the low incidence rate of which precludes statistical determination of its molecular characterizations. Despite recent genomic and transcriptomic profiling, the etiology of ameloblastomas remains poorly understood. Risk factors of ameloblastoma development are also largely unknown. Whole exome sequencing was performed on 11 mandibular ameloblastoma samples. We identified 2 convergent mutational signatures in ameloblastoma: 1) a signature found in multiple types of lung cancers with probable etiology of tobacco carcinogens (COSMIC signature 4) and 2) a signature present in gingivobuccal oral squamous cell carcinoma and correlated with tobacco-chewing habits (COSMIC signature 29). These mutational signatures highlight tobacco usage or related mutagens as one possible risk factor of ameloblastoma, since the association of BRAF mutations and smoking was demonstrated in multiple studies. In addition to BRAF hotspot mutations (V600E), we observed clear inter- and intratumor heterogeneities. Interestingly, prior to BRAF mutation, important genes regulating odontogenesis mutated (e.g., corepressor BCOR), possibly playing important roles in tumorigenesis. Furthermore, recurrent mutations in the CDC73 gene, the germline mutations of which predispose patients to the development of jaw tumors, were found in 2 patients, which may lead to recurrence if not targeted by therapeutic drugs. Our unbiased profiling of coding regions of ameloblastoma genomes provides insights to the possible etiology of mandibular ameloblastoma and highlights potential disease risk factors for screening and prevention, especially for Asian patients. Because of the limited sample size and incomplete habitual, dietary, and occupational data, a causal link between tobacco usage and ameloblastoma still requires further investigations.

Top 5 Need Statements

Introduction. The Stanford Biodesign process is a needs-driven approach to innovation which begins in the clinical setting and environment and is championed by practicing clinicians and surgeons. Here, our team applied the Stanford Biodesign process through clinical immersion to identify potential unmet clinical needs in the field of head and neck surgery, brainstormed and prototyped solutions to solve the top unmet need, and developed a commercialized medical device. Methods. The team underwent the 3 phases of the Biodesign process: identify, invent, and implement. The team underwent clinical immersion and followed head and neck surgeons from the Department of Head and Neck Surgery for a duration of 1 month. The needs identified were then filtered through a structured process using predefined filters, and a top need was chosen. After multiple rounds of brainstorming and prototyping, a final concept was developed. Results. The team collected 111 unmet needs and designed the in vivo surgical lighting concept that eventually led to the development of the KLARO™ in vivo surgical lighting device with a commercial partner. KLARO™ is a fully flexible 4.6-mm diameter light-emitting diode light strip that is freely bendable to be safely placed into deep cavities during open surgeries. Conclusion. The Biodesign process provides a standardized way to turn these needs into solution to advance the field of head and neck surgery and improve the outcome of patients.

Simple Summary Squamous cell carcinoma of the head and neck (SCCHN) is a heterogeneous group of tumors arising from squamous cells lining different anatomic sites. This type of malignancy has been mainly investigated by focusing primarily on tumor cells, but recent evidence highlighted the importance of the tumor microenvironment (TME) in cancer growth, progression and metastasis. Hence, we hypothesized that dysregulated matrisomal components could have a common association with patient survival, irrespective of the subsite of origin of the SCCHN. Using bioinformatic methods and public datasets, we successfully identified a gene panel with prognostic value in HPV-negative and non-metastatic node-negative tumors and demonstrated its association with immune cell infiltration. Abstract Squamous cell carcinoma of the head and neck (SCCHN) is common worldwide and related to several risk factors including smoking, alcohol consumption, poor dentition and human papillomavirus (HPV) infection. Different etiological factors may influence the tumor microenvironment and play a role in dictating response to therapeutics. Here, we sought to investigate whether an early-stage SCCHN-specific prognostic matrisome-derived gene signature could be identified for HPV-negative SCCHN patients (n = 168), by applying a bioinformatics pipeline to the publicly available SCCHN-TCGA dataset. We identified six matrisome-derived genes with high association with prognostic outcomes in SCCHN. A six-gene risk score, the SCCHN TMI (SCCHN-tumor matrisome index: composed of MASP1, EGFL6, SFRP5, SPP1, MMP8 and P4HA1) was constructed and used to stratify patients into risk groups. Using machine learning-based deconvolution methods, we found that the risk groups were characterized by a differing abundance of infiltrating immune cells. This work highlights the key role of immune infiltration cells in the overall survival of patients affected by HPV-negative SCCHN. The identified SCCHN TMI represents a genomic tool that could potentially aid patient stratification and selection for therapy in these patients.

Cutaneous squamous cell carcinoma (cSCC) is a common skin cancer. Most patients who develop metastases (2&ndash, 5%) present with advanced disease that requires a combination of radical surgery and adjuvant radiation therapy. There are few effective therapies for refractory disease. In this study, we describe novel patient-derived cell lines from cSCC metastases of the head and neck (designated UW-CSCC1 and UW-CSCC2). The cell lines genotypically and phenotypically resembled the original patient tumor and were tumorogenic in mice. Differences in cancer-related gene expression between the tumor and cell lines after various culturing conditions could be largely reversed by xenografting and reculturing. The novel drug susceptibilities of UW-CSCC1 and an irradiated subclone UW-CSCC1-R to drugs targeting cell cycle, PI3K/AKT/mTOR, and DNA damage pathways were observed using high-throughput anti-cancer and kinase-inhibitor compound libraries, which correlate with either copy number variations, targetable mutations and/or the upregulation of gene expression. A secondary screen of top hits in all three cell lines including PIK3CA-targeting drugs supports the utility of targeting the PI3K/AKT/mTOR pathway in this disease. UW-CSCC cell lines are thus useful preclinical models for determining targetable pathways and candidate therapeutics.

Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) is common in Southern China and South-East Asia. Immune checkpoint blockade (ICB) is being studied in NPC and initial monotherapy ICB studies show early promise. Currently, lack of representative NPC models limit the preclinical studies to evaluate the efficacy and safety of novel ICB and combination regimens. Hence, there is a need to develop and characterize a mouse model with human immune system for testing immunotherapy. Here, we engrafted NPC-PDX in immunodeficient NSG mice, with a successful growth rate of 16.7% (6 out of 36), and humanized mouse NPC-PDX model was established subsequently. Of note, EBV latent membrane protein-1 was retained in the NPC in both NSG and humanized mice as revealed by IHC staining. There was an increase in tumor-infiltrating CD4+ T cells and a decrease in CD8+ cytotoxic T cells in humanized mice, when compared to the immune cells profile in circulation. Intriguingly, the expression levels of various exhaustion markers, namely PD-1, CTLA4 and TIM-3 were upregulated, particularly in the tumor-infiltrating T cells. Therefore, the use of ICB, either alone or in combination, may restore the function of anti-tumor immune effector cells. Taken together, we have established a humanized mouse NPC-PDX model, which plausibly provides a robust platform to test for the efficacy and safety of ICB and combination therapy regimens. Citation Format: Wai Nam LIU, Shin Yie FONG, Wilson Wei Sheng TAN, Sue Yee TAN, Min LIU, Narayanan Gopalakrishna IYER, Darren Wan-Teck LIM, Qingfeng CHEN. Establishment and characterization of humanized mouse NPC-PDX model for testing immunotherapy [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 5060.

Immune checkpoint blockade (ICB) monotherapy shows early promise for the treatment of nasopharyngeal carcinoma (NPC) in patients. Nevertheless, limited representative NPC models hamper preclinical studies to evaluate the efficacy of novel ICB and combination regimens. In the present study, we engrafted NPC biopsies in non-obese diabetic-severe combined immunodeficiency interleukin-2 receptor gamma chain-null (NSG) mice and established humanized mouse NPC-patient-derived xenograft (NPC-PDX) model successfully. Epstein&ndash, Barr virus was detected in the NPC in both NSG and humanized mice as revealed by Epstein&ndash, Barr virus-encoded small RNA (EBER) in situ hybridization (ISH) and immunohistochemical (IHC) staining. In the NPC-bearing humanized mice, the percentage of tumor-infiltrating CD8+ cytotoxic T cells was lowered, and the T cells expressed higher levels of various inhibitory receptors, such as programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) than those in blood. The mice were then treated with nivolumab and ipilimumab, and the anti-tumor efficacy of combination immunotherapy was examined. In line with paired clinical data, the NPC-PDX did not respond to the treatment in terms of tumor burden, whilst an immunomodulatory response was elicited in the humanized mice. From our results, human proinflammatory cytokines, such as interferon-gamma (IFN-&gamma, ) and interleukin-6 (IL-6) were significantly upregulated in plasma. After treatment, there was a decrease in CD4/CD8 ratio in the NPC-PDX, which also simulated the modulation of intratumoral CD4/CD8 profile from the corresponding donor. In addition, tumor-infiltrating T cells were re-activated and secreted more IFN-&gamma, towards ex vivo stimulation, suggesting that other factors, including soluble mediators and metabolic milieu in tumor microenvironment may counteract the effect of ICB treatment and contribute to the tumor progression in the mice. Taken together, we have established and characterized a novel humanized mouse NPC-PDX model, which plausibly serves as a robust platform to test for the efficacy of immunotherapy and may predict clinical outcomes in NPC patients.

BACKGROUND The comeasurement of both genomic and transcriptomic signatures in single cells is of fundamental importance to accurately assess how the genetic information correlates with the transcriptomic phenotype. However, existing technologies have low throughput and laborious work flows. METHODS We developed a new method for concurrent sequencing of the transcriptome and targeted genomic regions (CORTAD-seq) within the same single cell on an automated microfluidic platform. The method was compatible with the downstream library preparation, allowing easy integration into existing next-generation sequencing work flows. We incorporated a single-cell bioinformatics pipeline for transcriptome and mutation analysis. RESULTS As proof of principle, we applied CORTAD-seq to lung cancer cell lines to dissect the cellular consequences of mutations that result in resistance to targeted therapy. We obtained a mean detection of 6000 expressed genes and an exonic rate of 50%. The targeted DNA-sequencing data achieved a 97.8% detection rate for mutations and allowed for the identification of copy number variations and haplotype construction. We detected expression signatures of tyrosine kinase inhibitor (TKI) resistance, epidermal growth factor receptor (EGFR) amplification, and expansion of the T790M mutation among resistant cells. We also identified characteristics for TKI resistance that were independent of EGFR T790M, indicating that other alterations are required for resistance in this context. CONCLUSIONS CORTAD-seq allows assessment of the interconnection between genetic and transcriptomic changes in single cells. It is operated on an automated, commercially available single-cell isolation platform, making its implementation straightforward.

Highlights • Adenoid Cystic Carcinoma is a malignant neoplasm originating in both major and minor salivary glands. • It is characterized by slow progression, local invasiveness and perineural invasion. • It may present as a hypoglossal nerve palsy. • When the diagnosis is in doubt, we suggest examination under anasthesia and deep biopsy., Introduction We describe a patient with an unusual presentation of an isolated hypoglossal nerve palsy as a result of perineural invasion (PI) from adenoid cystic carcinoma (ACC). We will also discuss the diagnostic pitfalls as well as present a short literature review of adenoid cystic carcinomas and suggest improvement to the current diagnostic algorithm for isolated hypoglossal nerve palsies. Presentation of case A 63 year old Malay female presented with progressive dysphagia and slurred speech for one year. Physical examination showed unilateral right tongue wasting, fasciculation and deviation to the right. An MRI showed atrophy of the tongue due to denervation and subsequently she was treated in a neurology clinic for 8 months. Due to lack of improvement, she was referred to our surgical unit and underwent examination under anaesthesia (EUA) and biopsy. Histology showed adenoid cystic carcinoma with perineural involvement, resulting in lower motor neuron signs. She underwent radiotherapy to the base of her tongue (70 Gy/35#). A PET-CT one month post treatment showed complete response. Discussion Adenoid cystic carcinoma (ACC) is a salivary gland neoplasm. It is characterized by local invasiveness with frequent recurrence and indolent growth. It affects major salivary glands more than minor salivary glands. In malignancies that have a propensity for PI such as ACC, patients may present atypically with nerve palsies. In infiltrative lesions, the primary tumour may not be evident on magnetic resonance imaging. Therefore, to achieve a diagnosis, a high index of suspicion is required. When the diagnosis is in question, deep biopsy and positron emission tomography may be useful.

Background Metastatic nasopharyngeal carcinoma (NPC) is commonly treated with palliative chemotherapy. The purpose of this study was to review the feasibility of metastasectomy for metachronous pulmonary and hepatic metastases from NPC. Methods We present 6 patients who developed metachronous metastases from NPC (4 patients with pulmonary metastases and 2 patients with hepatic metastases) and underwent curative resection. Results Four patients are still alive with no recurrence of NPC after metastasectomy. Two patients died with postoperative survival periods of 57 and 70 months and recurrence-free intervals of 14 and 39 months, respectively. Conclusion Metastasectomy is a feasible option for the treatment of metachronous and resectable oligometastatic NPC to the lung and liver. Application of appropriate selection criteria would be required. © 2015 Wiley Periodicals, Inc. Head Neck, 2015

Pembrolizumab is a humanized IgG4 Kappa monoclonal programmed death receptor 1 directed antibody FDA approved for the first line treatment of metastatic non-small cell lung carcinoma (NSCLC) expressing >=50% PD-L1. Pseudoprogression in this context has rarely been reported. We encountered a patient within our community practice who received treatment with pembrolizumab and demonstrated radiologic features of pseudoprogression initially followed by clinical progression where upon histologic evaluation favored pseudoprogression over progression. The aims of this study are as follows: Firstly, to describe the clinico-pathologic-radiologic aspects of this patient’s treatment journey; secondly, to histologically characterize a lesion that was biopsied which showed clinical features of progression, but histologically, pseudoprogression; thirdly, to perform detailed flow cytometric analysis of lymphocytes obtained through the biopsy to characterize pseudoprogression. This is a single patient case study performed by reviewing clinical notes, radiology, and histology. Samples obtained on biopsy were further characterized by flow cytometry. A 72-year-old male patient with small volume metastatic squamous cell lung carcinoma with a tumor proportion score of 100% for PD-L1, was initially treated with radiation (20Gy) to palliate worsening dyspnea caused by airway obstruction. He had good local control with improvement in dyspnea and subsequently requested for observation only. Serial imaging revealed the development of an abdominal wall nodule. Before long, his metastatic disease became symptomatic and he was treated with first line pembrolizumab. Three weeks after his first dose, he presented with severe abdominal wall pain and a new palpable abdominal wall mass. Imaging performed confirmed the presence of a new abdominal wall mass in contrast to a reduction in size of his pulmonary lesions. This was thus assessed as pseudoprogression, and he was continued on treatment with radiologic response noted three weeks later in all lesions. He discontinued treatment due to cost at this point, and subsequently restarted treatment upon radiologic progression of disease. On restarting treatment, his abdominal wall nodule increased in size and ulcerated. True tumor progression was considered prompting biopsy of the abdominal wall nodule to enable stratification into clinical trials. However, histologic evaluation showed chronically inflamed granulation tissue with no microscopic evidence of malignancy suggesting pseudoprogression once again instead. The patient went on to receive radiotherapy to the abdominal wall nodule, and a serial scan demonstrated a reduction in size of the abdominal wall nodule and stable pulmonary disease. Flow cytometric analysis of biopsy tissue revealed predominantly CD45+ cells, 69.5% of which were CD3+. CD45+CD3+CD56- cells comprised CD4+ (27.9%), CD8+ (64.9%), CD4+PD1+ (46.7%), CD8+PD+ (37.7%). Further analysis by flow and mass cytometry is ongoing, and attempts are also being made to assess the tumor antigen specificity of the T-cells. In a patient with clinically immunogenic cancer responding to intermittent anti-PD1 therapy, we observed varying clinico-radiologic responses across his metastatic lesions, and a pathologic evaluation of a clinically progressing lesion revealed pseudoprogression instead. Citation Format: Tiffany Hennedige, Daniel Tan, Narayanan Gopalakrishna Iyer, Amit Jain. Pseudoprogression of metastatic abdominal wall nodules in a patient with lung carcinoma treated with pembrolizumab [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr B161.

Metastatic nasopharyngeal carcinoma (NPC) is commonly treated with palliative chemotherapy. The purpose of this study was to review the feasibility of metastasectomy for metachronous pulmonary and hepatic metastases from NPC.We present 6 patients who developed metachronous metastases from NPC (4 patients with pulmonary metastases and 2 patients with hepatic metastases) and underwent curative resection.Four patients are still alive with no recurrence of NPC after metastasectomy. Two patients died with postoperative survival periods of 57 and 70 months and recurrence-free intervals of 14 and 39 months, respectively.Metastasectomy is a feasible option for the treatment of metachronous and resectable oligometastatic NPC to the lung and liver. Application of appropriate selection criteria would be required.

p300 and cyclic AMP response element-binding protein (CBP) are adenoviral E1A-binding proteins involved in multiple cellular processes, and function as transcriptional co-factors and histone acetyltransferases. Germline mutation of CBP results in Rubinstein-Taybi syndrome, which is characterized by an increased predisposition to childhood malignancies. Furthermore, somatic mutations of p300 and CBP occur in a number of malignancies. Chromosome translocations target CBP and, less commonly, p300 in acute myeloid leukemia and treatment-related hematological disorders. p300 mutations in solid tumors result in truncated p300 protein products or amino-acid substitutions in critical protein domains, and these are often associated with inactivation of the second allele. A mouse model confirms that p300 and CBP function as suppressors of hematological tumor formation. The involvement of these proteins in critical tumorigenic pathways (including TGF-beta, p53 and Rb) provides a mechanistic route as to how their inactivation could result in cancer.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death in the world. The multikinase inhibitor sorafenib only demonstrated marginal improvement in overall survival for advanced disease prompted the search for alternative treatment options. Human mesenchymal stem cells (MSCs) have the ability to home to tumor cells. However, its functional roles on the tumor microenvironment remain controversial. Herein, we showed that conditioned media derived from human fetal MSC (CM-hfMSCs) expressed high level of the insulin growth factor binding proteins IGFBPs and can sequester free insulin-like growth factors (IGFs) to inhibit HCC cell proliferation. The inhibitory effect of IGFBPs on IGF signaling was further evident from the reduction of activated IGF-1R and PI3K/Akt, leading eventually to the induction of cell cycle arrest. We also demonstrated that CM-hfMSCs could enhance the therapeutic efficacy of sorafenib and sunitinib. To the best of our knowledge, this is the first report to show that CM-hfMSCs has a tumor-specific, antiproliferative effect that is not observed with normal human hepatocyte cells and patient-derived matched normal tissues. Our results thus suggest that CM-hfMSCs can provide a useful tool to design alternative/adjuvant treatment strategies for HCC, especially in related function to potentiate the effects of chemotherapeutic drugs.

True integration of clinical staging and molecular prognostic biomarkers has been hampered by a lack of comprehensive data sets with adequate power. In the last two years, The Cancer Genome Atlas (TCGA) has generated and made available a repository of rich, high volume -omics datasets including molecular profiling together with matched clinical data. Methods: Clinical and transcriptomics data were downloaded for TCGA datasets (38 projects) representing a total of 14,043 patients. Matched expression and clinical data was available for 34 cohorts, covering 10554 patients (median n=270, range 15-1091) and survival data was available for 24 cohorts (7854 patients, median 294 per cohort), with a median follow-up of 10.7 months (range 1.9 to 61 months). Prediction models were constructed based on the latest AJCC staging guide, a novel five gene molecular prognostic signature specifically derived for each cancer type, and a combined model utilising both. Accuracy of survival prediction was calculated as the area under the receiver operator characteristic curve (AUC), based on 2-year overall survival prediction. Results: Pan-cancer analyses demonstrate accuracy of clinical staging from 0.55-0.91 (median 0.72), while molecular prognostication varies from 0.7-0.99 (median 0.84). The combined model is consistently more accurate, 0.71-0.99 (median 0.89, p 0.7) suggests an important need for more accurate prognostic models in this subtype. Conclusion: The potential role for molecular staging as an adjunct to clinical staging remains undefined. In this study, we demonstrate for the first time the importance of molecular prognostication across a range of cancer sub-types, but especially where conventional staging performs poorly. The latter sub-group is further enriched for squamous cell cancers, where molecular information offers dramatic improvement in accuracy (+0.15 to AUC), and hence, should be prioritized for assessment of molecular signatures. The lack of integrating molecular data could also reflect limitations in our understanding of tumour biology, which in turn needs to be translated into potential actionable targets and therapeutic benefit. Citation Format: Nicholas Shannon, Melissa Ching Ching Teo, Narayanan Gopalakrishna Iyer. Does molecular staging trump clinical staging: a pan-cancer, big-data analysis of TCGA data [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 561. doi:10.1158/1538-7445.AM2017-561

Frontal sinus cancer provides challenging management issues and reconstruction is equally as difficult as resection in these cancers.

Tumor heterogeneity is an important concept in the carcinogenesis of solid tumors, and forms the background for the cancer-stem cell (CSCs) hypothesis. Emerging data suggests however that there is plasticity within various cancer sub-populations, and that CSCs exists in a contextually regulated equilibrium, which is multi-directional and less rigid than previously hypothesized. The aim of this study was to establish an in vitro system that recapitulates stem cell plasticity in head and neck squamous cell cancers (HNSCC), and identify factors that play a role in the maintenance and re-population of CSCs. Tumor spheres were established using patient-derived tumor cells via anchorage-independent cell culture techniques. RT-PCR showed higher expression of KLF4, SOX2 and Nanog in tumor spheres compared to monolayer culture cells. Cells grown as tumor spheres were more resistant to γ-radiation, 5-fluorouracil, cisplatin and etoposide treatment compared to cells grown in monolayer culture. Using the ALDEFLUOR assays to identify CSCs, we showed that more cells in tumor spheres had high aldehyde dehydrogenase (ALD+ cells) activity. Monolayer cultures were subject to single cell cloning to generate clones with high and low ALD+ fractions. As expected, ALDHigh clones showed higher expression of stem cell markers Oct4, Bmi1 and Nanog and EMT markers N-Cadherin, Slug, Snail, β-Catenin, Vimentin compared to ALDLow clones. When ALDHigh clones from HNSCC cells were cultured over time, ALD+ fractions were found to reduce gradually and equilibrate at a specified ALD+ fraction specific to each cell line grown in regular culture media. When growth factors EGF and/or insulin were added to the media, ALD+ fractions could be maintained at higher levels as compared to baseline. ALDHigh clones also showed increased EGFR and IGF-1R phosphorylation when grown in regular culture conditions, with increased activation of downstream factors involving the AKT and ERK pathways compared with ALDLow clones. Blocking these pathways using specific inhibitors against EGFR and IGFR reduced stem cell fractions drastically. Taken together, these results show that HNSCC CSCs exhibit plasticity, where the maintenance of the stem cell fraction was dependent on the EGF and IGF pathways, which are therefore vulnerable to therapeutic targeting. Citation Format: Hui Sun Leong, Pui Hoon Sew, Fui Teen Chong, Daniel Shao-Weng Tan, Narayanan Gopalakrishna Iyer. Growth factor signaling is critical in the maintenance of cancer stem cell population in head and neck squamous cell cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 258. doi:10.1158/1538-7445.AM2013-258