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1.
Cancer Immunol Res ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023967

RESUMO

Macrophages are among the most common cells in the colorectal cancer microenvironment, but their prognostic significance is incompletely understood. Using multiplexed immunofluorescence for CD68, CD86, IRF5, MAF, MRC1 (CD206), and KRT (cytokeratins) combined with digital image analysis and machine learning, we assessed the polarization spectrum of tumor-associated macrophages in 931 colorectal carcinomas. We then applied Cox proportional hazards regression to assess prognostic survival associations of intraepithelial and stromal densities of M1-like and M2-like macrophages while controlling for potential confounders, including stage and microsatellite instability status. We found that high tumor stromal density of M2-like macrophages was associated with worse cancer-specific survival, whereas tumor stromal density of M1-like macrophages was not significantly associated with better cancer-specific survival. High M1:M2 density ratio in tumor stroma was associated with better cancer-specific survival. Overall macrophage densities in tumor intraepithelial or stromal regions were not prognostic. These findings suggested that macrophage polarization state, rather than their overall density, was associated with cancer-specific survival, with M1- and M2-like macrophage phenotypes exhibiting distinct prognostic roles. These results highlight the utility of a multimarker strategy to assess the macrophage polarization at single-cell resolution within the tumor microenvironment.

2.
JAMA Oncol ; 6(10): e202948, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32789511

RESUMO

Importance: Pancreatic cancer is the third-leading cause of cancer death in the United States; however, few high-risk groups have been identified to facilitate early diagnosis strategies. Objective: To evaluate the association of diabetes duration and recent weight change with subsequent risk of pancreatic cancer in the general population. Design, Setting, and Participants: This cohort study obtained data from female participants in the Nurses' Health Study and male participants in the Health Professionals Follow-Up Study, with repeated exposure assessments over 30 years. Incident cases of pancreatic cancer were identified from self-report or during follow-up of participant deaths. Deaths were ascertained through reports from the next of kin, the US Postal Service, or the National Death Index. Data collection was conducted from October 1, 2018, to December 31, 2018. Data analysis was performed from January 1, 2019, to June 30, 2019. Exposures: Duration of physician-diagnosed diabetes and recent weight change. Main Outcome and Measures: Hazard ratios (HRs) for subsequent development of pancreatic cancer. Results: Of the 112 818 women (with a mean [SD] age of 59.4 [11.7] years) and 46 207 men (with a mean [SD] age of 64.7 [10.8] years) included in the analysis, 1116 incident cases of pancreatic cancers were identified. Compared with participants with no diabetes, those with recent-onset diabetes had an age-adjusted HR for pancreatic cancer of 2.97 (95% CI, 2.31-3.82) and those with long-standing diabetes had an age-adjusted HR of 2.16 (95% CI, 1.78-2.60). Compared with those with no weight loss, participants who reported a 1- to 4-lb weight loss had an age-adjusted HR for pancreatic cancer of 1.25 (95% CI, 1.03-1.52), those with a 5- to 8-lb weight loss had an age-adjusted HR of 1.33 (95% CI, 1.06-1.66), and those with more than an 8-lb weight loss had an age-adjusted HR of 1.92 (95% CI, 1.58-2.32). Participants with recent-onset diabetes accompanied by weight loss of 1 to 8 lb (91 incident cases per 100 000 person-years [95% CI, 55-151]; HR, 3.61 [95% CI, 2.14-6.10]) or more than 8 lb (164 incident cases per 100 000 person-years [95% CI, 114-238]; HR, 6.75 [95% CI, 4.55-10.00]) had a substantially increased risk for pancreatic cancer compared with those with neither exposure (16 incident cases per 100 000 person-years; 95% CI, 14-17). Incidence rates were even higher among participants with recent-onset diabetes and weight loss with a body mass index of less than 25 before weight loss (400 incident cases per 100 000 person-years) or whose weight loss was not intentional judging from increased physical activity or healthier dietary choices (334 incident cases per 100 000 person-years). Conclusions and Relevance: This study demonstrates that recent-onset diabetes accompanied by weight loss is associated with a substantially increased risk for developing pancreatic cancer. Older age, previous healthy weight, and no intentional weight loss further elevate this risk.

3.
Surg Pathol Clin ; 13(3): 485-502, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32773196

RESUMO

HER2 (ERBB2) is a member of the ERBB family of receptor tyrosine kinases and functions to drive signaling in the RAS/RAF/MEK/ERK and PI3K/AKT/mTOR pathways. Overall, approximately 2-3% of CRCs exhibit ERBB2 amplification. Multiple phase II clinical trials have now shown that ERBB2 amplification can be predictive of response to anti-ERBB2 targeted therapy. Consequently, recently released guidelines from the National Comprehensive Cancer Network recommend treatment with anti-ERBB2 targeted therapy for RAS wild-type, ERBB2-amplified metastatic CRC. While circumspection is still needed, ERBB2 amplification has now emerged as the next standard-of-care biomarker for metastatic CRC, expanding targeted therapy options for these patients.

4.
EBioMedicine ; 57: 102860, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32652320

RESUMO

BACKGROUND: Tumour budding and poorly differentiated clusters (PDC) represent forms of tumour invasion. We hypothesised that T-cell densities (reflecting adaptive anti-tumour immunity) might be inversely associated with tumour budding and PDC in colorectal carcinoma. METHODS: Utilising 915 colon and rectal carcinomas in two U.S.-wide prospective cohort studies, and multiplex immunofluorescence combined with machine learning algorithms, we assessed CD3, CD4, CD8, CD45RO (PTPRC), and FOXP3 co-expression patterns in lymphocytes. Tumour budding and PDC at invasive fronts were quantified by digital pathology and image analysis using the International tumour Budding Consensus Conference criteria. Using covariate data of 4,420 incident colorectal cancer cases, inverse probability weighting (IPW) was integrated with multivariable logistic regression analysis that assessed the association of T-cell subset densities with tumour budding and PDC while adjusting for selection bias due to tissue availability and potential confounders, including microsatellite instability status. FINDINGS: Tumour budding counts were inversely associated with density of CD3+CD8+ [lowest vs. highest: multivariable odds ratio (OR), 0.50; 95% confidence interval (CI), 0.35-0.70; Ptrend < 0.001] and CD3+CD8+CD45RO+ cells (lowest vs. highest: multivariable OR, 0.44; 95% CI, 0.31-0.63; Ptrend < 0.001) in tumour epithelial region. Tumour budding levels were associated with higher colorectal cancer-specific mortality (multivariable hazard ratio, 2.13; 95% CI, 1.57-2.89; Ptrend < 0.001) in Cox regression analysis. There were no significant associations of PDC with T-cell subsets. INTERPRETATION: Tumour epithelial naïve and memory cytotoxic T cell densities are inversely associated with tumour budding at invasive fronts, suggesting that cytotoxic anti-tumour immunity suppresses tumour microinvasion.

5.
Cell ; 182(3): 655-671.e22, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32603654

RESUMO

Checkpoint blockade with antibodies specific for the PD-1 and CTLA-4 inhibitory receptors can induce durable responses in a wide range of human cancers. However, the immunological mechanisms responsible for severe inflammatory side effects remain poorly understood. Here we report a comprehensive single-cell analysis of immune cell populations in colitis, a common and severe side effect of checkpoint blockade. We observed a striking accumulation of CD8 T cells with highly cytotoxic and proliferative states and no evidence of regulatory T cell depletion. T cell receptor (TCR) sequence analysis demonstrated that a substantial fraction of colitis-associated CD8 T cells originated from tissue-resident populations, explaining the frequently early onset of colitis symptoms following treatment initiation. Our analysis also identified cytokines, chemokines, and surface receptors that could serve as therapeutic targets for colitis and potentially other inflammatory side effects of checkpoint blockade.

6.
Cancer Epidemiol Biomarkers Prev ; 29(8): 1586-1595, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32467349

RESUMO

BACKGROUND: Insulin-like growth factor-1 receptor (IGF1R) signaling is important in pancreatic ductal adenocarcinoma (PDAC) biology, but little is known regarding IGF1R expression and patient characteristics and outcomes. METHODS: In 365 patients with resected PDAC, we evaluated IGF1R protein expression using IHC on whole-slide sections and IGF1R genomic status using next-generation sequencing. Associations of IGF1R expression, measured by H-scores incorporating staining intensity and proportion of positive tumor cells, with disease-free survival (DFS) and overall survival (OS) were evaluated in 317 and 321 patients, respectively, using Cox regression adjusting for known prognostic factors. RESULTS: Higher IGF1R expression in tumor cells was associated with worse DFS comparing highest versus lowest expression tertiles [median DFS, 10.8 vs. 16.1 months; adjusted hazard ratio (HR), 1.73; 95% confidence interval (CI), 1.24-2.44; P trend = 0.002] and worse OS (median OS, 17.4 vs. 25.8 months; HR, 1.39; 95% CI, 1.00-1.92; P trend = 0.046). The association between high IGF1R expression and reduced DFS was identified primarily among patients with a preoperative body mass index ≥25 kg/m2 (HR, 4.27; 95% CI, 2.03-8.96, comparing extreme tertiles; P interaction = 0.032). KRAS-mutant tumors had greater IGF1R expression, and IGF1R expression in tumor epithelium was inversely correlated with that in stromal cells. Mutations in IGF1R were infrequent, and no overt loss-of-function alterations were identified. Higher IGF1R expression was modestly associated with higher gene copy number (Pearson correlation coefficient = 0.26, P < 0.001). CONCLUSIONS: Higher IGF1R protein expression was associated with worse patient outcomes in resected PDAC. IMPACT: IGF1R expression in PDAC represents a potential biomarker to guide patient selection for more aggressive, multidrug regimens in the adjuvant setting.

8.
Clin Cancer Res ; 26(16): 4326-4338, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32439699

RESUMO

PURPOSE: Although high T-cell density is a well-established favorable prognostic factor in colorectal cancer, the prognostic significance of tumor-associated plasma cells, neutrophils, and eosinophils is less well-defined. EXPERIMENTAL DESIGN: We computationally processed digital images of hematoxylin and eosin (H&E)-stained sections to identify lymphocytes, plasma cells, neutrophils, and eosinophils in tumor intraepithelial and stromal areas of 934 colorectal cancers in two prospective cohort studies. Multivariable Cox proportional hazards regression was used to compute mortality HR according to cell density quartiles. The spatial patterns of immune cell infiltration were studied using the GTumor:Immune cell function, which estimates the likelihood of any tumor cell in a sample having at least one neighboring immune cell of the specified type within a certain radius. Validation studies were performed on an independent cohort of 570 colorectal cancers. RESULTS: Immune cell densities measured by the automated classifier demonstrated high correlation with densities both from manual counts and those obtained from an independently trained automated classifier (Spearman's ρ 0.71-0.96). High densities of stromal lymphocytes and eosinophils were associated with better cancer-specific survival [P trend < 0.001; multivariable HR (4th vs 1st quartile of eosinophils), 0.49; 95% confidence interval, 0.34-0.71]. High GTumor:Lymphocyte area under the curve (AUC0,20µm; P trend = 0.002) and high GTumor:Eosinophil AUC0,20µm (P trend < 0.001) also showed associations with better cancer-specific survival. High stromal eosinophil density was also associated with better cancer-specific survival in the validation cohort (P trend < 0.001). CONCLUSIONS: These findings highlight the potential for machine learning assessment of H&E-stained sections to provide robust, quantitative tumor-immune biomarkers for precision medicine.

9.
Cell ; 181(4): 832-847.e18, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32304665

RESUMO

Obesity is a major modifiable risk factor for pancreatic ductal adenocarcinoma (PDAC), yet how and when obesity contributes to PDAC progression is not well understood. Leveraging an autochthonous mouse model, we demonstrate a causal and reversible role for obesity in early PDAC progression, showing that obesity markedly enhances tumorigenesis, while genetic or dietary induction of weight loss intercepts cancer development. Molecular analyses of human and murine samples define microenvironmental consequences of obesity that foster tumorigenesis rather than new driver gene mutations, including significant pancreatic islet cell adaptation in obesity-associated tumors. Specifically, we identify aberrant beta cell expression of the peptide hormone cholecystokinin (Cck) in response to obesity and show that islet Cck promotes oncogenic Kras-driven pancreatic ductal tumorigenesis. Our studies argue that PDAC progression is driven by local obesity-associated changes in the tumor microenvironment and implicate endocrine-exocrine signaling beyond insulin in PDAC development.

10.
Mod Pathol ; 33(10): 1910-1921, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32291395

RESUMO

The spectrum of neoplasms associated with DICER1 variants continues to expand, with the recent addition of primary "DICER1-associated central nervous system sarcoma" (DCS). DCS is a high-grade malignancy predominantly affecting pediatric patients. Six pediatric DCS were identified through a combination of clinical diagnostic studies, archival inquiry, and interinstitutional collaboration. Clinical, histologic, immunohistologic, and molecular features were examined. Genomic findings in the 6 DCS were compared with those in 14 additional DICER1-associated tumors sequenced with the same assay. The six patients presented at ages 3-15 years with CNS tumors located in the temporal (n = 2), parietal (n = 1), fronto-parietal (n = 1), and frontal (n = 2) lobes. All underwent surgical resection. Histologic examination demonstrated high-grade malignant spindle cell tumors with pleuropulmonary blastoma-like embryonic "organoid" features and focal rhabdomyoblastic differentiation; immature cartilage was seen in one case. Immunohistochemically, there was patchy desmin and myogenin staining, and patchy loss of H3K27me3, and within eosinophilic cytoplasmic globules, alfa-fetoprotein staining. Biallelic DICER1 variants were identified in all cases, with germline variants in two of five patients tested. DCS demonstrated genomic alterations enriched for Ras pathway activation and TP53 inactivation. Tumor mutational burden was significantly higher in the 6 DCS tumors than in 14 other DICER1-associated tumors examined (mean 12.9 vs. 6.8 mutations/Mb, p = 0.035). Postoperative care included radiation (n = 5) and chemotherapy (n = 3); at the last follow-up, three patients were alive without DCS, and three had died of disease. Our analysis expands the clinical, histologic, immunohistological, and molecular spectrum of DCS, identifying distinctive features that can aid in the diagnosis, multidisciplinary evaluation, and treatment of DCS.

11.
Mol Cancer Res ; 18(6): 883-890, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32165453

RESUMO

Accumulating evidence suggests that metabolic reprogramming has a critical role in carcinogenesis and tumor progression. The usefulness of formalin-fixed paraffin-embedded (FFPE) tissue material for metabolomics analysis as compared with fresh frozen tissue material remains unclear. LC/MS-MS-based metabolomics analysis was performed on 11 pairs of matched tumor and normal tissues in both FFPE and fresh frozen tissue materials from patients with colorectal carcinoma. Permutation t test was applied to identify metabolites with differential abundance between tumor and normal tissues. A total of 200 metabolites were detected in the FFPE samples and 536 in the fresh frozen samples. The preservation of metabolites in FFPE samples was diverse according to classes and chemical characteristics, ranging from 78% (energy) to 0% (peptides). Compared with the normal tissues, 34 (17%) and 174 (32%) metabolites were either accumulated or depleted in the tumor tissues derived from FFPE and fresh frozen samples, respectively. Among them, 15 metabolites were common in both FFPE and fresh frozen samples. Notably, branched chain amino acids were highly accumulated in tumor tissues. Using KEGG pathway analyses, glyoxylate and dicarboxylate metabolism, arginine and proline, glycerophospholipid, and glycine, serine, and threonine metabolism pathways distinguishing tumor from normal tissues were found in both FFPE and fresh frozen samples. This study demonstrates that informative data of metabolic profiles can be retrieved from FFPE tissue materials. IMPLICATIONS: Our findings suggest potential value of metabolic profiling using FFPE tumor tissues and may help to shape future translational studies through developing treatment strategies targeting metabolites.

12.
Br J Cancer ; 122(9): 1367-1377, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32157241

RESUMO

BACKGROUND: Histological lymphocytic reaction is regarded as an independent prognostic marker in colorectal cancer. Considering the lack of adequate statistical power, adjustment for selection bias and comprehensive tumour molecular data in most previous studies, we investigated the strengths of the prognostic associations of lymphocytic reaction in colorectal carcinoma by utilising an integrative database of two prospective cohort studies. METHODS: We examined Crohn's-like reaction, intratumoural periglandular reaction, peritumoural reaction and tumour-infiltrating lymphocytes in 1465 colorectal carcinoma cases. Using covariate data of 4420 colorectal cancer cases in total, inverse probability-weighted Cox proportional hazard regression model was used to control for selection bias (due to tissue availability) and potential confounders, including stage, MSI status, LINE-1 methylation, PTGS2 and CTNNB1 expression, KRAS, BRAF and PIK3CA mutations, and tumour neoantigen load. RESULTS: Higher levels of each lymphocytic reaction component were associated with better colorectal cancer-specific survival (Ptrend < 0.002). Compared with cases with negative/low intratumoural periglandular reaction, multivariable-adjusted HRs were 0.55 (95% CI, 0.42-0.71) in cases with intermediate reaction and 0.20 (95% CI, 0.12-0.35) in cases with high reaction. These relationships were consistent in strata of MSI status or neoantigen loads (Pinteraction > 0.2). CONCLUSIONS: The four lymphocytic reaction components are prognostic biomarkers in colorectal carcinoma.

13.
Cancer Epidemiol Biomarkers Prev ; 29(1): 133-140, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31666286

RESUMO

BACKGROUND: We hypothesized that the risk of colorectal cancer in night-shift workers might be different according to insulin receptor substrate status. METHODS: Among 77,470 eligible women having night work assessed in the Nurses' Health Study, we documented a total of 1,397 colorectal cancer cases, of which 304 or 308 had available data on IRS1 and IRS2, respectively. We used duplication-method Cox proportional hazards regression analysis for competing risks to calculate HRs and 95% confidence intervals (CI) for each colorectal cancer subtype. We measured tumor IRS1 or IRS2 expression by immunohistochemistry (IHC). RESULTS: Compared with women who never worked night shifts, those working ≥15 years night shifts had a marginal trend of increased overall risk of colorectal cancer (P trend = 0.06; multivariable HR = 1.20; 95% CI, 0.99-1.45). Longer duration of night-shift work was associated with a higher risk of IRS2-positive tumors (multivariable HR = 2.69; 95% CI, 1.48-4.89; P trend = 0.001, ≥15 years night shifts vs. never) but not with IRS2-negative tumors (multivariable HR = 0.90; 95% CI, 0.54-1.51; P trend = 0.72; P heterogeneity for IRS2 = 0.008). Similarly, the corresponding multivariable HRs were 1.81 for IRS1-positive tumors (95% CI, 0.94-3.48; P trend = 0.06) and 1.13 for IRS1-negative tumors (95% CI, 0.71-1.80; P trend = 0.56; P heterogeneity for IRS1 = 0.02). CONCLUSIONS: Our molecular pathologic epidemiology data suggest a potential role of IRS in mediating carcinogenesis induced by night-shift work. IMPACT: Although these findings need validation, rotating night shift might increase colorectal cancer risk in women with abnormal insulin receptor pathways.

14.
J Pathol ; 250(4): 397-408, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31880318

RESUMO

Fusobacterium nucleatum (F. nucleatum), which has been associated with colorectal carcinogenesis, can impair anti-tumour immunity, and actively invade colon epithelial cells. Considering the critical role of autophagy in host defence against microorganisms, we hypothesised that autophagic activity of tumour cells might influence the amount of F. nucleatum in colorectal cancer tissue. Using 724 rectal and colon cancer cases within the Nurses' Health Study and the Health Professionals Follow-up Study, we evaluated autophagic activity of tumour cells by immunohistochemical analyses of BECN1 (beclin 1), MAP1LC3 (LC3), and SQSTM1 (p62) expression. We measured the amount of F. nucleatum DNA in tumour tissue by quantitative polymerase chain reaction (PCR). We conducted multivariable ordinal logistic regression analyses to examine the association of tumour BECN1, MAP1LC3, and SQSTM1 expression with the amount of F. nucleatum, adjusting for potential confounders, including microsatellite instability status; CpG island methylator phenotype; long-interspersed nucleotide element-1 methylation; and KRAS, BRAF, and PIK3CA mutations. Compared with BECN1-low cases, BECN1-intermediate and BECN1-high cases were associated with lower amounts of F. nucleatum with odds ratios (for a unit increase in three ordinal categories of the amount of F. nucleatum) of 0.54 (95% confidence interval, 0.29-0.99) and 0.31 (95% confidence interval, 0.16-0.60), respectively (Ptrend < 0.001 across ordinal BECN1 categories). Tumour MAP1LC3 and SQSTM1 levels were not significantly associated with the amount of F. nucleatum (Ptrend > 0.06). Tumour BECN1, MAP1LC3, and SQSTM1 levels were not significantly associated with patient survival (Ptrend > 0.10). In conclusion, tumour BECN1 expression is inversely associated with the amount of F. nucleatum in colorectal cancer tissue, suggesting a possible role of autophagy in the elimination of invasive microorganisms. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Autofagia/genética , Neoplasias Colorretais/genética , Fusobacterium nucleatum/genética , Microambiente Tumoral/genética , Idoso , Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinogênese/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias Colorretais/imunologia , Feminino , Fusobacterium nucleatum/imunologia , Humanos , Masculino , Instabilidade de Microssatélites , Mutação/genética
15.
Cancer Epidemiol Biomarkers Prev ; 28(11): 1868-1875, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31427306

RESUMO

BACKGROUND: Leukocyte telomere length has been associated with risk of subsequent pancreatic cancer. Few prospective studies have evaluated the association of prediagnostic leukocyte telomere length with pancreatic cancer survival. METHODS: We prospectively examined the association of prediagnostic leukocyte telomere length with overall survival (OS) time among 423 participants diagnosed with pancreatic adenocarcinoma between 1984 and 2008 within the Health Professionals Follow-up Study, Nurses' Health Study, Physicians' Health Study, and Women's Health Initiative. We measured prediagnostic leukocyte telomere length in banked blood samples using quantitative PCR. Cox proportional hazards models were used to estimate HRs for OS with adjustment for potential confounders. We also evaluated 10 SNPs at the telomerase reverse transcriptase locus. RESULTS: Shorter prediagnostic leukocyte telomere length was associated with reduced OS among patients with pancreatic cancer (P trend = 0.04). The multivariable-adjusted HR for OS comparing the lowest with highest quintiles of leukocyte telomere length was 1.39 (95% confidence interval, 1.01-1.93), corresponding to a 3-month difference in median OS time. In an analysis excluding cases with blood collected within 2 years of cancer diagnosis, the association was moderately stronger (HR, 1.55; 95% confidence interval, 1.09-2.21; comparing the lowest with highest quintiles; P trend = 0.01). No prognostic association or effect modification for the prognostic association of prediagnostic leukocyte telomere length was noted in relation to the studied SNPs. CONCLUSIONS: Prediagnostic leukocyte telomere length was associated with pancreatic cancer survival. IMPACT: Prediagnostic leukocyte telomere length can be a prognostic biomarker in pancreatic cancer.

16.
Cancer Immunol Res ; 7(8): 1230-1236, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31217164

RESUMO

Immunotherapy with checkpoint inhibitors, such as the programmed death-1 (PD-1) antibodies pembrolizumab and nivolumab, are effective in a variety of tumors, yet not all patients respond. Tumor microsatellite instability-high (MSI-H) has emerged as a biomarker of response to checkpoint blockade, leading to the tissue agnostic approval of pembrolizumab in MSI-H cancers. Here we describe a patient with MSI-H colorectal cancer that was treated with this immune checkpoint inhibitor and exhibited progression of disease. We examined this intrinsic resistance through genomic, transcriptional, and pathologic characterization of the patient's tumor and the associated immune microenvironment. The tumor had typical MSI-H molecular features, including a high neoantigen load. We also identified biallelic loss of the gene for ß2-microglobulin (B2M), whose product is critical for antigen presentation. Immune infiltration deconvolution analysis of bulk transcriptome data from this anti-PD-1-resistant tumor and hundreds of other colorectal cancer specimens revealed a high natural killer cell and M2 macrophage infiltration in the patient's cancer. This was confirmed by single-cell transcriptome analysis and multiplex immunofluorescence. Our study provides insight into resistance in MSI-H tumors and suggests immunotherapeutic strategies in additional genomic contexts of colorectal cancer.

17.
Cancer Causes Control ; 30(8): 799-811, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31069578

RESUMO

An important premise of epidemiology is that individuals with the same disease share similar underlying etiologies and clinical outcomes. In the past few decades, our knowledge of disease pathogenesis has improved, and disease classification systems have evolved to the point where no complex disease processes are considered homogenous. As a result, pathology and epidemiology have been integrated into the single, unified field of molecular pathological epidemiology (MPE). Advancing integrative molecular and population-level health sciences and addressing the unique research challenges specific to the field of MPE necessitates assembling experts in diverse fields, including epidemiology, pathology, biostatistics, computational biology, bioinformatics, genomics, immunology, and nutritional and environmental sciences. Integrating these seemingly divergent fields can lead to a greater understanding of pathogenic processes. The International MPE Meeting Series fosters discussion that addresses the specific research questions and challenges in this emerging field. The purpose of the meeting series is to: discuss novel methods to integrate pathology and epidemiology; discuss studies that provide pathogenic insights into population impact; and educate next-generation scientists. Herein, we share the proceedings of the Fourth International MPE Meeting, held in Boston, MA, USA, on 30 May-1 June, 2018. Major themes of this meeting included 'integrated genetic and molecular pathologic epidemiology', 'immunology-MPE', and 'novel disease phenotyping'. The key priority areas for future research identified by meeting attendees included integration of tumor immunology and cancer disparities into epidemiologic studies, further collaboration between computational and population-level scientists to gain new insight on exposure-disease associations, and future pooling projects of studies with comparable data.


Assuntos
Epidemiologia , Patologia Molecular , Humanos , Neoplasias/epidemiologia , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia
18.
Cancer Epidemiol Biomarkers Prev ; 28(7): 1246-1251, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31028081

RESUMO

BACKGROUND: No consensus guideline has been established for microsatellite instability testing in upper gastrointestinal tract cancers. This study aims to determine whether targeted cancer next-generation sequencing can accurately detect microsatellite instability in upper gastrointestinal tract cancers and screen for patients with Lynch syndrome. METHODS: In a cohort of 645 upper gastrointestinal tract cancers, targeted next-generation sequencing assessed microsatellite instability by identifying characteristic insertion and deletion mutations. Sequencing classification was compared with mismatch repair protein IHC. Cancers with microsatellite instability by sequencing were analyzed using a testing protocol to identify patients with Lynch syndrome. RESULTS: Sequencing identified microsatellite instability in 3.6% (23/645) of upper gastrointestinal tract cancers, including 28% (8/29) of small intestinal and 9% (9/97) of gastric carcinomas. In 20 cancers classified as having microsatellite instability, 19 demonstrated loss of expression of MLH1, PMS2, MSH2, or MSH6, and one cancer was indeterminate by IHC. In contrast, 52 control cancers demonstrated retained expression of all mismatch repair proteins. Using targeted sequencing as the initial screening test, 1.1% (7/645) of patients were identified to have pathogenic germline variants confirming a diagnosis of Lynch syndrome. CONCLUSIONS: Targeted cancer next-generation sequencing is an accurate first-line test to detect microsatellite instability in upper gastrointestinal tract cancers. IMPACT: This study provides a proof of concept for the use of targeted next-generation sequencing to detect microsatellite instability and screen for Lynch syndrome.

19.
Cancer Discov ; 9(6): 738-755, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30952657

RESUMO

KRAS is the most frequently mutated oncogene. The incidence of specific KRAS alleles varies between cancers from different sites, but it is unclear whether allelic selection results from biological selection for specific mutant KRAS proteins. We used a cross-disciplinary approach to compare KRASG12D, a common mutant form, and KRASA146T, a mutant that occurs only in selected cancers. Biochemical and structural studies demonstrated that KRASA146T exhibits a marked extension of switch 1 away from the protein body and nucleotide binding site, which activates KRAS by promoting a high rate of intrinsic and guanine nucleotide exchange factor-induced nucleotide exchange. Using mice genetically engineered to express either allele, we found that KRASG12D and KRASA146T exhibit distinct tissue-specific effects on homeostasis that mirror mutational frequencies in human cancers. These tissue-specific phenotypes result from allele-specific signaling properties, demonstrating that context-dependent variations in signaling downstream of different KRAS mutants drive the KRAS mutational pattern seen in cancer. SIGNIFICANCE: Although epidemiologic and clinical studies have suggested allele-specific behaviors for KRAS, experimental evidence for allele-specific biological properties is limited. We combined structural biology, mass spectrometry, and mouse modeling to demonstrate that the selection for specific KRAS mutants in human cancers from different tissues is due to their distinct signaling properties.See related commentary by Hobbs and Der, p. 696.This article is highlighted in the In This Issue feature, p. 681.

20.
Cancer Causes Control ; 30(6): 637-649, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30963391

RESUMO

BACKGROUND: A preventive potential of high calcium intake against colorectal cancer has been indicated for distal colon cancer, which is inversely associated with high-level CpG island methylator phenotype (CIMP), high-level microsatellite instability (MSI), and BRAF and PIK3CA mutations. In addition, BRAF mutation is strongly inversely correlated with KRAS mutation. We hypothesized that the association between calcium intake and colon cancer risk might vary by these molecular features. METHODS: We prospectively followed 88,506 women from the Nurses' Health Study and 47,733 men from the Health Professionals Follow-up Study for up to 30 years. Duplication-method Cox proportional cause-specific hazards regression was used to estimate multivariable hazard ratios (HRs), and 95% confidence intervals (95% CIs) for the associations between calcium intake and the risk of colon cancer subtypes. By Bonferroni correction, the α-level was adjusted to 0.01. RESULTS: Based on 853 colon cancer cases, the inverse association between dietary calcium intake and colon cancer risk differed by CIMP status (pheterogeneity = 0.01). Per each 300 mg/day increase in intake, multivariable HRs were 0.84 (95% CI 0.76-0.94) for CIMP-negative/low and 1.12 (95% CI 0.93-1.34) for CIMP-high. Similar differential associations were suggested for MSI subtypes (pheterogeneity = 0.02), with the corresponding HR being 0.86 (95% CI 0.77-0.95) for non-MSI-high and 1.10 (95% CI 0.92-1.32) for MSI-high. No differential associations were observed by BRAF, KRAS, or PIK3CA mutations. CONCLUSION: The inverse association between dietary calcium intake and colon cancer risk may be specific to CIMP-negative/low and possibly non-MSI-high subtypes.


Assuntos
Cálcio/administração & dosagem , Neoplasias do Colo/patologia , Ilhas de CpG/genética , Proteínas Proto-Oncogênicas B-raf/genética , Idoso , Neoplasias do Colo/genética , Metilação de DNA , Feminino , Seguimentos , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Mutação , Fenótipo , Modelos de Riscos Proporcionais , Risco
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