Search

BACKGROUND: In the phase II multicohort CheckMate 142 study, nivolumab plus low-dose (1 mg/kg) ipilimumab provided robust and durable clinical benefit with a manageable safety profile in previously treated patients with microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (mCRC) at 13.4- and 25.4-month median follow-up (Overman MJ, Lonardi S, Wong KYM et al. Durable clinical benefit with nivolumab plus ipilimumab in DNA mismatch repair-deficient/microsatellite instability-high metastatic colorectal cancer. J Clin Oncol. 2018;36:773-779. Overman MJ, Lonardi S, Wong KYM, et al. Nivolumab plus low-dose ipilimumab in previously treated patients with microsatellite instability-high/mismatch repair deficient metastatic colorectal cancer: long-term follow-up. J Clin Oncol. 2019;37:635). Here, we present results from the 4-year follow-up of these patients. PATIENTS AND METHODS: Patients received nivolumab (3 mg/kg) plus low-dose (1 mg/kg) ipilimumab every 3 weeks (four doses) followed by nivolumab (3 mg/kg) every 2 weeks until disease progression. Primary endpoint was investigator-assessed objective response rate (ORR; as per RECIST version 1.1). RESULTS: A total of 119 patients were treated; 76% had ≥2 prior lines of therapy. Median follow-up was 50.9 months (range 46.9-62.7 months). Median duration of therapy was 24.9 months [95% confidence interval (CI) 15.8-33.2 months]. Investigator-assessed ORR increased from 55% (95% CI 45% to 64%) at 13.4 months to 65% (95% CI 55% to 73%) at 50.9 months with a disease control rate of 81% (95% CI 72% to 87%). The complete response rate increased from 3% at 13.4 months to 13% at 50.9 months. Partial responses were observed in 52% of patients; 21% had stable disease, and 12% had progressive disease. Median time to response was 2.8 months (range 1.1-37.1 months), and median duration of response was not reached (range 1.4+ to 58.0+ months). At data cut-off, 37 (48%) patients had ongoing responses. Median progression-free survival was not reached [95% CI 38.4 months-not estimable (NE)], and median overall survival was not reached (95% CI NE). Grade 3-4 treatment-related adverse events (TRAEs) were observed in 32% of patients; 13% of patients had any-grade TRAEs leading to discontinuation. CONCLUSIONS: The results confirm long-term benefit of nivolumab plus low-dose ipilimumab for previously treated patients with MSI-H/dMMR mCRC. The safety profile was manageable with no new safety signals. ispartof: ANNALS OF ONCOLOGY vol:33 issue:10 pages:1052-1060 ispartof: location:England status: published

The diagnosis and treatment of gastrointestinal (GI) bleeding secondary to malignancy can be challenging. Endoscopy is the gold standard to diagnose and treat gastrointestinal bleeding but clinical characteristics and outcomes of patients with malignancy-related bleeding are not well understood. This study aims to look at clinical characteristics, endoscopic findings, safety and clinical outcomes of endoscopic interventions for GI malignancy-related bleeding.We retrospectively reviewed outcomes of patients with confirmed GI malignancies who underwent endoscopy for GI bleeding at MD Anderson Cancer Center between 2010 and 2019. Cox hazard analysis was conducted to identify factors associated with survival.A total of 313 patients were included, with median age of 59 years; 74.8% were male. The stomach (30.0%) was the most common tumor location. Active bleeding was evident endoscopically in 47.3% of patients. Most patients (77.3%) did not receive endoscopic treatment. Of the patients who received endoscopic treatment, 57.7% had hemostasis. No endoscopy-related adverse events were recorded. Endoscopic treatment was associated with hemostasis (P 0.001), but not decreased recurrent bleeding or mortality. Absence of active bleeding on endoscopy, stable hemodynamic status at presentation, lower cancer stage, and surgical intervention were associated with improved survival.This study indicates that endoscopy is a safe diagnostic tool in this patient population; while endoscopic treatments may help achieve hemostasis, it may not decrease the risk of recurrent bleeding or improve survival.

BackgroundAdoptive T-cell transfer has become an attractive therapeutic approach for hematological malignancies but shows poor activity against large and heterogeneous solid tumors. Interleukin-12 (IL-12) exhibits potent antitumor efficacy against solid tumors, but its clinical application has been stalled because of toxicity. Here, we aimed to develop a safe approach to IL-12 T-cell therapy for eliminating large solid tumors.MethodsWe generated a cell membrane-anchored IL-12 (aIL12), a tumor-targeted IL-12 (ttIL12), and a cell membrane-anchored and ttIL-12 (attIL12) and a cell membrane-anchored and tumor-targeted ttIL-12 (attIL12) armed T cells, chimeric antigen receptor-T cells, and T cell receptor-T (TCR-T) cells with each. We compared the safety and efficacy of these armed T cells in treating osteosarcoma patient-derived xenograft tumors and mouse melanoma tumors after intravenous infusions of the armed T cells.ResultsattIL12-T cell infusion showed remarkable antitumor efficacy in human and mouse large solid tumor models. Mechanistically, attIL12-T cells targeted tumor cells expressing cell-surface vimentin, enriching effector T cell and interferon γ production in tumors, which in turn stimulates dendritic cell maturation for activating secondary T-cell responses and tumor antigen spreading. Both attIL12- and aIL12-T-cell transfer eliminated peripheral cytokine release and the associated toxic effects.ConclusionsThis novel approach sheds light on the safe application of IL-12-based T-cell therapy for large and heterogeneous solid tumors.

Colorectal cancer is the second leading cause of cancer deaths worldwide, with a 5-year relative survival of 14% in patients with metastatic colorectal cancer (mCRC). Patients with BRAF V600E mutations, which occur in ∼10%-15% of patients with mCRC, have a poorer prognosis compared with those with wild-type BRAF tumours. The combination of the BRAF inhibitor encorafenib with the epidermal growth factor receptor inhibitor cetuximab currently represents the only chemotherapy-free targeted therapy approved in the USA and Europe for previously treated patients with BRAF V600E-mutated mCRC. As a class, BRAF inhibitors are associated with dermatologic, gastrointestinal, and renal events, as well as pyrexia and secondary skin malignancies. Adverse event (AE) profiles of specific BRAF inhibitors vary, however, and are affected by the specific agents given in combination. In patients with mCRC, commonly reported AEs of cetuximab monotherapy include infusion reactions and dermatologic toxicities. Data from the phase III BEACON CRC study indicate that the combination of encorafenib with cetuximab has a distinct safety profile. Here we review the most frequently reported AEs that occurred with this combination in BEACON CRC and best practices for managing and mitigating AEs that require more than standard supportive care., Highlights • Encorafenib + cetuximab has a distinct safety profile in patients with BRAF V600E-mutated metastatic colorectal cancer. • Effective management strategies can mitigate the impact of AEs, prolonging treatment duration and benefits. • We provide guidance on managing gastrointestinal, skin, and renal AEs. • Specific guidance is given for the management of arthralgia, myalgia, fatigue, asthenia, headache, and pyrexia.

Background Oncogenic mutations in PIK3CA are prevalent in diverse cancers and can be targeted with inhibitors of the phosphoinositide-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. Analysis of circulating tumor DNA (ctDNA) provides a minimally invasive approach to detect clinically actionable PIK3CA mutations. Patients and methods We analyzed PIK3CA hotspot mutation frequency by droplet digital PCR (QX 200; BioRad) using 16 ng of unamplified plasma-derived cell-free DNA from 68 patients with advanced solid tumors (breast cancer, n = 41; colorectal cancer, n = 13; other tumor types, n = 14). Results quantified as variant allele frequencies (VAFs) were compared with previous testing of archival tumor tissue and with patient outcomes. Results Of 68 patients, 58 (85%) had PIK3CA mutations in tumor tissue and 43 (74%) PIK3CA mutations in ctDNA with an overall concordance of 72% (49/68, κ = 0.38). In a subset analysis, which excluded samples from 26 patients known not to have disease progression at the time of sample collection, we found an overall concordance of 91% (38/42; κ = 0.74). PIK3CA-mutated ctDNA VAF of ≤8.5% (5% trimmed mean) showed a longer median survival compared with patients with a higher VAF (15.9 versus 9.4 months; 95% confidence interval 6.7-17.1 months; P = 0.014). Longitudinal analysis of ctDNA in 18 patients with serial plasma collections (range 2-22 time points, median 5) showed that those with a decrease in PIK3CA VAF had a longer time to treatment failure (TTF) compared with patients with an increase or no change (10.7 versus 2.6 months; P = 0.048). Conclusions Detection of PIK3CA mutations in ctDNA is concordant with testing of archival tumor tissue. Low quantity of PIK3CA-mutant ctDNA is associated with longer survival and a decrease in PIK3CA-mutant ctDNA on therapy is associated with longer TTF., Highlights • Testing for PIK3CA mutations in ctDNA is concordant with testing of tumor tissue. • High PIK3CA-mutant abundance in ctDNA was associated with shorter survival. • Increasing PIK3CA-mutant abundance in serial blood samples was associated with shorter TTF. • Longitudinal monitoring of PIK3CA-mutant ctDNA tracked with cancer clinical course.

Purpose: Mutations in KRAS are the most common oncogenic drivers. Sotorasib (AMG510), a covalent inhibitor selectively targeting KRASG12C, was recently approved for the treatment of KRASG12C-mutated non-small cell lung cancer (NSCLC). However, the clinical efficacy of sotorasib and other KRASG12C inhibitors is limited by intrinsic resistance in colorectal cancer (CRC) and by the rapid emergence of acquired resistance in all treated solid tumors. Therefore, there is an urgent need to develop novel combination therapies to overcome sotorasib resistance and to maximize its efficacy. Experimental Design: A panel of KRASG12C-mutated cell lines from NSCLC, CRC and pancreatic cancer (PC) were treated with sotorasib alone or in combination with BCL-XL proteolysis targeting chimera (PROTAC, such as DT2216) to assess effects on cell viability, colony formation and apoptosis. To identify mechanisms underlying sotorasib+DT2216 combination responses, we analyzed KRAS downstream signaling and expression of BCL-2 family proteins, and performed co-immunoprecipitation of BCL-XL to evaluate its interaction with pro-apoptotic BH3-only proteins. Finally, therapeutic efficacy of sotorasib alone and in combination with DT2216 was evaluated in vivo using different tumor xenograft models. Results: We observed heterogeneous responses to sotorasib alone, whereas its combination with DT2216 strongly inhibited viability of KRASG12C cell lines that partially responded to sotorasib treatment. Mechanistically, co-treatment with DT2216 inhibited sotorasib-induced BCL-XL/BIM interaction leading to enhanced apoptosis. Furthermore, DT2216 co-treatment significantly improved the antitumor efficacy of sotorasib in vivo. Conclusions: Our findings suggest that due to cytostatic activity, the efficacy of sotorasib is limited, and therefore its combination with a pro-apoptotic agent DT2216 shows synergistic responses and can potentially overcome resistance. Citation Format: Sajid Khan, Janet Wiegand, Peiyi Zhang, Wanyi Hu, Dinesh Thummuri, Vivekananda Budamagunta, Nan Hua, Lingtao Jin, Carmen J. Allegra, Edmund S. Kopetz, Maria Zajac-Kaye, Frederic J. Kaye, Guangrong Zheng, Daohong Zhou. A BCL-XL PROTAC degrader DT2216 synergizes with KRASG12C inhibitors for effectively treating KRASG12C-mutated cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5313.

Targeted methylation sequencing of plasma cell-free DNA (cfDNA) has a potential to expand liquid biopsies to patients with tumors without detectable oncogenic alterations, which can be potentially useful in early diagnosis.We developed a comprehensive methylation sequencing assay targeting 9223 CpG sites consistently hypermethylated according to The Cancer Genome Atlas. Next, we carried out a clinical validation of our method using plasma cfDNA samples from 78 patients with advanced colorectal cancer, non-small-cell lung cancer (NSCLC), breast cancer or melanoma and compared results with patients' outcomes.Median methylation scores in plasma cfDNA samples from patients on therapy were lower than from patients off therapy (4.74 versus 85.29; P = 0.001). Of 68 plasma samples from patients off therapy, methylation scores detected the presence of cancer in 57 (83.8%), and methylation-based signatures accurately classified the underlying cancer type in 45 (78.9%) of these. Methylation scores were most accurate in detecting colorectal cancer (96.3%), followed by breast cancer (91.7%), melanoma (81.8%) and NSCLC (61.1%), and most accurate in classifying the underlying cancer type in colorectal cancer (88.5%), followed by NSCLC (81.8%), breast cancer (72.7%) and melanoma (55.6%). Low methylation scores versus high were associated with longer survival (10.4 versus 4.4 months, P 0.001) and longer time-to-treatment failure (2.8 versus 1.6 months, P = 0.016).Comprehensive targeted methylation sequencing of 9223 CpG sites in plasma cfDNA from patients with common advanced cancers detects the presence of cancer and underlying cancer type with high accuracy. Methylation scores in plasma cfDNA correspond with treatment outcomes.

Additional file 1: Figure S1. A. Immunofluorescence analysis of the indicate antibody followed by secondary antibody labeled with Alexa Fluor 488 in the HCT116 and HCT116 MR cells. DAPI was included to stain the nucleus. B. PD-L1 has a protective role in the nucleus. Western blot analysis was performed to evaluate Caspase 9, Caspase 3 and Bcl2 expression in HCT116 and HCT116 MR cells. C. Sensitivity of LIM1215 and LIM1215 MR cells to the increasing concentrations of BAY86–9766 (0.01–10 μM) after 96 h treatment and evaluated for proliferation by MTT staining. The results are the average ± SD of three independent experiments each done in triplicate. D. Analysis of intracellular signaling pathways by Western blot analysis in LIM1215 and LIM1215-MR cells. Total cell protein extracts (50 μg) were subjected to immunoblotting with the indicated antibodies, as described in Materials and Methods. Anti-tubulin antibody was used for normalization of protein extract content.

Background The practice of salvaging recurrent rectal cancer has evolved. The aim of this study was to define the evolving salvage potential over time among patients with locally recurrent disease, and to identify durable determinants of long-term success. Methods The study included consecutive patients with recurrent rectal cancer undergoing multimodal salvage with curative intent between 1988 and 2012. Predictors of long-term survival were defined by Cox regression analysis and compared over time. Re-recurrence and subsequent treatments were evaluated. Results After multidisciplinary evaluation of 229 patients, salvage therapy with curative intent included preoperative chemotherapy and/or radiotherapy (73·4 per cent; with 41·3 per cent undergoing repeat pelvic irradiation), surgical salvage resection with or without intraoperative irradiation (36·2 per cent), followed by postoperative adjuvant chemotherapy (38·0 per cent). Multivisceral resection was undertaken in 47·2 per cent and bone resection in 29·7 per cent. The R0 resection rate was 80·3 per cent. After a median follow-up of 56·5 months, the 5-year overall survival rate was 50 per cent in 2005–2012, markedly increased from 32 per cent in 1988–1996 (P = 0·044). Long-term success was associated with R0 resection (P = 0·017) and lack of secondary failure (P = 0·003). Some 125 patients (54·6 per cent) developed further recurrence at a median of 19·4 months after salvage surgery. Repeat operative rescue was feasible in 21 of 48 patients with local re-recurrence alone and in 17 of 77 with distant re-recurrence, with a median survival of 19·8 months after further recurrence. Conclusion The long-term salvage potential for recurrent rectal cancer improved significantly over time, with the introduction of an individualized treatment algorithm of multimodal treatments and surgical salvage. Durable predictors of long-term success were R0 resection at salvage operation, avoidance of secondary failure, and feasibility of repeat rescue after re-recurrence.

Background Cell-free DNA (cfDNA) from plasma offers easily obtainable material forKRAS mutation analysis. Novel, multiplex, and accurate diagnostic systems using small amounts of DNA are needed to further the use of plasma cfDNA testing in personalized therapy. Patients and methods Samples of 16 ng of unamplified plasma cfDNA from 121 patients with diverse progressing advanced cancers were tested with aKRASG12/G13 multiplex assay to detect the seven most common mutations in the hotspot of exon 2 using droplet digital polymerase chain reaction (ddPCR). The results were retrospectively compared to mutation analysis of archival primary or metastatic tumor tissue obtained at different points of clinical care. Results Eighty-eight patients (73%) hadKRASG12/G13 mutations in archival tumor specimens collected on average 18.5 months before plasma analysis, and 78 patients (64%) hadKRASG12/G13 mutations in plasma cfDNA samples. The two methods had initial overall agreement in 103 (85%) patients (kappa, 0.66; ddPCR sensitivity, 84%; ddPCR specificity, 88%). Of the 18 discordant cases, 12 (67%) were resolved by increasing the amount of cfDNA, using mutation-specific probes, or re-testing the tumor tissue, yielding overall agreement in 115 patients (95%; kappa 0.87; ddPCR sensitivity, 96%; ddPCR specificity, 94%). The presence of ≥ 6.2% ofKRASG12/G13 cfDNA in the wild-type background was associated with shorter survival (P=0.001). Conclusion(s) Multiplex detection ofKRASG12/G13 mutations in a small amount of unamplified plasma cfDNA using ddPCR has good sensitivity and specificity and good concordance with conventional clinical mutation testing of archival specimens. A higher percentage of mutantKRASG12/G13 in cfDNA corresponded with shorter survival.

The purpose of this study was to determine the outcome of patients with colorectal cancer metastatic to the ovary and the impact of surgical oophorectomy on the outcome.We conducted a retrospective evaluation of patients with metastatic colorectal cancer to the ovary. Of 3776 female patients with colorectal cancer seen at MD Anderson from 2001-2008, 110 (2.9%) were identified as having metastases to the ovary. The Kaplan-Meier method and log-rank test were used to examine the survival functions.Seventy-one patients (64.5%) had disease metastatic to the ovary at the time of initial presentation; in 39 patients (35.5%) the ovaries were a site of relapse after previous curative colorectal surgical resection. Patients who presented with ovarian relapse after previous colorectal surgery and who underwent oophorectomy had a median survival of 50 months compared with 12 months for those who did not (P.0001). Patients with metastatic disease at the time of presentation who underwent oophorectomy had a median survival of 39.4 months vs. 18.2 months for those who did not.This retrospective analysis suggests that women with metastatic colorectal cancer metastatic to the ovary may derive a survival benefit from palliative oophorectomy.

This paper reports on a new technology for the realization of an optical waveguide layer in electrical-optical circuit boards. The technology is based on casting of transparent polysiloxanes as low cost, low loss (0,05 dB/cm at 850 nm) and high temperature stable (> 250°C) material system. The waveguide layer fabrication will be discussed as well as the preparation of suitable casting moulds. Further issues are the material and waveguide properties of optical polysiloxanes, the coupling to OE-modules, and the lamination of optical layers into printed circuit boards.

406 Background: Chemotherapy combined with inhibitors of VEGF signaling is associated with improved outcomes, but biomarkers of therapeutic benefit have been elusive. Cediranib (Ced) is an oral VEGFR tyrosine kinase inhibitor that has been investigated as a treatment for metastatic colorectal cancer (mCRC). Methods: 215 patients with progressive disease and no prior VEGF inhibitor therapy were enrolled in a randomized phase II study of FOLFOX + Ced 20mg/d, Ced 30mg/d or bevacizumab (Bev) 10mg/kg (Cunningham D, et al. J Clin Oncol 26: 2008 (May 20 suppl; abstr 4028). 36 CAFs were analyzed at 3 time points (baseline, wk 4, wk 8). Groups were dichotomized by median CAF value. Hazard ratios (HRs) were estimated from a Cox model with a single term. Results: Data were available for > 85% patients for each CAF. When pooled across all arms, several baseline CAFs including VEGF, interleukin (IL)-2Rα, IL-8 and PDGF were associated with improved PFS (Table). Low and high baseline CAF subgroups were evaluated for potential predictive CAFs. Pts with elevated baseline IL-8 did better with Ced 30mg/d than Bev (HR 0.6 for PFS, CI 0.3-1.0) while low IL-8 was associated with greater benefit from Bev than Ced (HR 2.1, CI 1.0 to 4.2). For Ced 20mg/d, PFS HRs were 0.9 (CI 0.5, 1.6) and 1.7 (CI 0.9, 3.2) for elevated and low baseline IL-8 respectively. Hepatocyte-growth factor (HGF) demonstrated a similar relationship, while a trend for the inverse association was seen with IP-10. Distinct patterns of cytokine modulation were seen between Ced and Bev during the 8 wks, including decreases of sVEGFR2, IL-13 and increases in osteopontin. Conclusions: Several potential prognostic factors for second-line mCRC therapy were identified including VEGF and IL-8. Further work in larger placebo-controlled studies is required to further evaluate predictive markers for VEGF signaling inhibitors. [Table: see text] [Table: see text]

The environmental stability of polydimethylsiloxane (PDMS)-based optical waveguides implemented in electrical-optical circuit boards has been tested against international standards. Temperature shock, moisture treatments, dry heat exposure as well as soldering float showed only a moderate impact on optical waveguide performance.

A large area (390/spl times/150 mm) flexible polymer optical waveguide foil and its production process is presented. The waveguide materials are highly transparent, refractive index tuned polysiloxanes. The waveguide layer is embedded between two flexible PCB laminates. The optical loss at 850 nm is

A hybrid electrical-optical circuit board is demonstrated using polysiloxane as low-loss and high-temperature stable waveguide material system. After board lamination at 180°C for two hours and a subsequent annealing at 230°C for 5 minutes the waveguide insertion loss is 0.05 dB/cm at 850 nm wavelength.

Combined effect of prior response and long interval upon clinical benefit on anti-EGFR clinical trial retreatment. (DOC 30Â kb)

Figure S1. Experimental timeline for generation of PDX/cell line-implanted hu-CB-BRGS mice. Figure S2. Expression of hPD-L1 on MDA-MB-231 TNBC cell line. MDA-MB-231 cells grown in culture were collected and stained for expression of human PD-L1. Figure S3. Human chimerism and cell numbers in TNBC MDA-MB-231 cell line implanted hu-CB-BRGS mice harvested at d11 and d21 post treatment. a, Equivalent human hematopoietic (left), T (middle, gate: hCD45+) and CD8 (right, gate: hCD45+,CD3+) chimerism in blood of humanized mice among experimental (d11 or d21 harvest, control (−) or anti-PD-1 treatment (+) groups. b, Human hematopoietic (hCD45+) and T (CD3+) cell numbers in lymph organs of TNBC-bearing hu-CB-BRGS mice at harvest. Figure S4. Immunohistochemistry analysis of human and mouse chimerism in TNBC MDA-MB-231 cell line implanted hu-CB-BRGS mice. a, Representative IHC slides from untreated and nivolumab-treated MDA-MB-231 tumors explanted from hu-CB-BRGS mice 11 or 21 days after start of treatment. b, Increased human T-cell (CD3) densities in tumors of hu-CB-BRGS mice treated with nivolumab for 21 days. Figure S5. Expression of CD25 (clone M-A251) on FoxP3+ CD4+ and CD8+ T cells (hCD45 + CD3+) in LN and spleens of hu-CB-BRGS mice. a, Representative flow cytometry staining and b, cumulative data showing percentage of FoxP3+ T cells (left) and percentage of CD25+ among the FoxP3+ T cells (right). Figure S6. Individual data points and expression of hPD-L1 on MDA-MB-231 TNBC cell line harvested from hu-CB-BRGS mice. a, Tumor growth curves of untreated (black), nivolumab-treated (red), OKI-179-treated (green) and combination (red) of the TNBC hu-CB-BRGS mice. b, Tumors were identified as mCD45-, hCD45-, Epcam+ or HLA-A,B,C+. Figure S7. Increased detection of human T cells in IHC sections from nivolumab-treated MSI-H PDX relative to untreated MSI-H PDX or nivolumab-treated MSS PDX. (PPTX 16200 kb)

Supplementary Methods. (DOCX 26 kb)

Supplementary Methods. (DOCX 26 kb)

Figure S1. Experimental timeline for generation of PDX/cell line-implanted hu-CB-BRGS mice. Figure S2. Expression of hPD-L1 on MDA-MB-231 TNBC cell line. MDA-MB-231 cells grown in culture were collected and stained for expression of human PD-L1. Figure S3. Human chimerism and cell numbers in TNBC MDA-MB-231 cell line implanted hu-CB-BRGS mice harvested at d11 and d21 post treatment. a, Equivalent human hematopoietic (left), T (middle, gate: hCD45+) and CD8 (right, gate: hCD45+,CD3+) chimerism in blood of humanized mice among experimental (d11 or d21 harvest, control (−) or anti-PD-1 treatment (+) groups. b, Human hematopoietic (hCD45+) and T (CD3+) cell numbers in lymph organs of TNBC-bearing hu-CB-BRGS mice at harvest. Figure S4. Immunohistochemistry analysis of human and mouse chimerism in TNBC MDA-MB-231 cell line implanted hu-CB-BRGS mice. a, Representative IHC slides from untreated and nivolumab-treated MDA-MB-231 tumors explanted from hu-CB-BRGS mice 11 or 21 days after start of treatment. b, Increased human T-cell (CD3) densities in tumors of hu-CB-BRGS mice treated with nivolumab for 21 days. Figure S5. Expression of CD25 (clone M-A251) on FoxP3+ CD4+ and CD8+ T cells (hCD45 + CD3+) in LN and spleens of hu-CB-BRGS mice. a, Representative flow cytometry staining and b, cumulative data showing percentage of FoxP3+ T cells (left) and percentage of CD25+ among the FoxP3+ T cells (right). Figure S6. Individual data points and expression of hPD-L1 on MDA-MB-231 TNBC cell line harvested from hu-CB-BRGS mice. a, Tumor growth curves of untreated (black), nivolumab-treated (red), OKI-179-treated (green) and combination (red) of the TNBC hu-CB-BRGS mice. b, Tumors were identified as mCD45-, hCD45-, Epcam+ or HLA-A,B,C+. Figure S7. Increased detection of human T cells in IHC sections from nivolumab-treated MSI-H PDX relative to untreated MSI-H PDX or nivolumab-treated MSS PDX. (PPTX 16200 kb)

Table S1. Experimental details and timeline for tumor growth studies in BRGS and hu-CB-BRGS mice. (DOCX 20 kb)

Table S1. Experimental details and timeline for tumor growth studies in BRGS and hu-CB-BRGS mice. (DOCX 20 kb)

Combined effect of prior response and long interval upon clinical benefit on anti-EGFR clinical trial retreatment. (DOC 30Â kb)

The functional roles of SNPs within the 8q24 gene desert in the cancer phenotype are not yet well understood. Here, we report that CCAT2, a novel long noncoding RNA transcript (lncRNA) encompassing the rs6983267 SNP, is highly overexpressed in microsatellite-stable colorectal cancer and promotes tumor growth, metastasis, and chromosomal instability. We demonstrate that MYC, miR–17–5p, and miR–20a are up-regulated by CCAT2 through TCF7L2-mediated transcriptional regulation. We further identify the physical interaction between CCAT2 and TCF7L2 resulting in an enhancement of WNT signaling activity. We show that CCAT2 is itself a WNT downstream target, which suggests the existence of a feedback loop. Finally, we demonstrate that the SNP status affects CCAT2 expression and the risk allele G produces more CCAT2 transcript. Our results support a new mechanism of MYC and WNT regulation by the novel lncRNA CCAT2 in colorectal cancer pathogenesis, and provide an alternative explanation of the SNP-conferred cancer risk.