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Background: Regular use of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) for a longer period has been inversely associated with colorectal cancer (CRC) risk. However, CRC is a heterogenic disease, and little is known regarding the associations with molecular pathological subtypes.Methods: Analyses included 2444 cases with a first diagnosis of CRC and 3130 healthy controls from a German population-based case control study. Tumor tissue samples were analyzed for major molecular pathological features: microsatellite instability (MSI), CpG island methylator phenotype, B-Raf proto-oncogene serine/threonine kinase (BRAF) mutation, and Kirsten rat sarcoma viral oncogene homolog gene (KRAS) mutation. Information on past and current use of NSAIDs, including aspirin, was obtained by standardized interviews. Multinomial logistic regression models were used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). All statistical tests were two-sided.Results: Regular use of NSAIDs was associated with a reduced CRC risk if tumors were MSS (OR = 0.66, 95% CI = 0.57 to 0.77), BRAF wildtype (OR = 0.67, 95% CI = 0.58 to 0.78), or KRAS wildtype (OR = 0.68, 95% CI = 0.58 to 0.80). Regular NSAID use was less clearly and mostly not statistically significantly associated with CRC risk reduction for MSI-high, BRAF-mutated, or KRAS-mutated CRC. In more specific analyses on MSI-high CRC, regular use of NSAIDs was associated with much stronger risk reduction in the absence of BRAF or KRAS mutations (OR = 0.34, 95% CI = 0.18 to 0.65) but not with KRAS- or BRAF-mutated MSI-high CRC (Pheterogeneity < .001). Results for just aspirin use were similar.Conclusion: Our study suggests variation in risk reduction of CRC subtypes following regular use of NSAIDs and aspirin. Regular use of NSAIDs and aspirin may be more strongly associated with risk reduction of MSI-high CRC without KRAS or BRAF mutation. [ABSTRACT FROM AUTHOR]

Radioiodine refractoriness in differentiated thyroid cancer remains an unsolved therapeutic problem. Response to retinoids might depend on specific genetic markers. In this retrospective analysis, associations between BRAF V600E and clinical outcomes after redifferentiation with retinoic acid (RA) and radioiodine therapy (RIT) were investigated. Thirteen patients with radioiodine-refractory (RAI-R) papillary thyroid cancer (PTC) were treated with 13-cis-RA followed by iodine-131 treatment at the Department of Endocrinology, Heidelberg University Hospital, Heidelberg, Germany. DNA sequencing was performed in formalin-fixed paraffin-embedded tissue. Clinical outcome parameters were tumor size, thyroglobulin, and radioiodine uptake in correlation to mutational status. Differences of each parameter were compared before and after RA/RIT. Initial response showed no difference in patients with BRAF V600E compared to patients with wild type. However, after a median follow-up of 2 and a half years, 2 out of 3 patients with BRAF V600E showed response compared to 5 out of 9 with wild type under consideration of all 3 parameters. In this small cohort, more RAI-R PTC patients with BRAF V600E receiving redifferentiation therapy showed response. Verification in a larger study population analyzing mutational status in patients with RAI-R PTC might be helpful to identify patients where redifferentiation therapy might lead to an improved outcome. [ABSTRACT FROM AUTHOR]

We aimed to validate the prognostic association of p16 expression in ovarian high‐grade serous carcinomas (HGSC) and to explore it in other ovarian carcinoma histotypes. p16 protein expression was assessed by clinical‐grade immunohistochemistry in 6525 ovarian carcinomas including 4334 HGSC using tissue microarrays from 24 studies participating in the Ovarian Tumor Tissue Analysis consortium. p16 expression patterns were interpreted as abnormal (either overexpression referred to as block expression or absence) or normal (heterogeneous). CDKN2A (which encodes p16) mRNA expression was also analyzed in a subset (n = 2280) mostly representing HGSC (n = 2010). Association of p16 expression with overall survival (OS) was determined within histotypes as was CDKN2A expression for HGSC only. p16 block expression was most frequent in HGSC (56%) but neither protein nor mRNA expression was associated with OS. However, relative to heterogeneous expression, block expression was associated with shorter OS in endometriosis‐associated carcinomas, clear cell [hazard ratio (HR): 2.02, 95% confidence (CI) 1.47–2.77, p < 0.001] and endometrioid (HR: 1.88, 95% CI 1.30–2.75, p = 0.004), while absence was associated with shorter OS in low‐grade serous carcinomas (HR: 2.95, 95% CI 1.61–5.38, p = 0.001). Absence was most frequent in mucinous carcinoma (50%), and was not associated with OS in this histotype. The prognostic value of p16 expression is histotype‐specific and pattern dependent. We provide definitive evidence against an association of p16 expression with survival in ovarian HGSC as previously suggested. Block expression of p16 in clear cell and endometrioid carcinoma should be further validated as a prognostic marker, and absence in low‐grade serous carcinoma justifies CDK4 inhibition. [ABSTRACT FROM AUTHOR]

Background: Earlier epidemiological studies indicate that associations between obesity and breast cancer risk may not only depend on menopausal status and use of exogenous hormones, but might also differ by tumor subtype. Here, we evaluated whether obesity is differentially associated with the risk of breast tumor subtypes, as defined by 6 immunohistochemical markers (ER, PR, HER2, Ki67, Bcl-2 and p53, separately and combined), in the prospective EPIC-Germany Study (n = 27,012).Methods: Formalin-fixed and paraffin-embedded (FFPE) tumor tissues of 657 incident breast cancer cases were used for histopathological analyses. Associations between BMI and breast cancer risk across subtypes were evaluated by multivariable Cox regression models stratified by menopausal status and hormone therapy (HT) use.Results: Among postmenopausal non-users of HT, higher BMI was significantly associated with an increased risk of less aggressive, i.e. ER+, PR+, HER2-, Ki67low, Bcl-2+ and p53- tumors (HR per 5 kg/m2: 1.44 [1.10, 1.90], p = 0.009), but not with risk of more aggressive tumor subtypes. Among postmenopausal users of HT, BMI was significantly inversely associated with less aggressive tumors (HR per 5 kg/m2: 0.68 [0.50, 0.94], p = 0.018). Finally, among pre- and perimenopausal women, Cox regression models did not reveal significant linear associations between BMI and risk of any tumor subtype, although analyses by BMI tertiles showed a significantly lower risk of less aggressive tumors for women in the highest tertile (HR: 0.55 [0.33, 0.93]).Conclusion: Overall, our results suggest that obesity is related to risk of breast tumors with lower aggressiveness, a finding that requires replication in larger-scale analyses of pooled prospective data. [ABSTRACT FROM AUTHOR]

Caudal type homeobox 2 (CDX2) has been well‑established as a diagnostic marker for colorectal cancer (CRC); however, less is known about its regulation, particularly its potential interactions with the DNA repair proteins, adenomatous polyposis coli (APC) and β‑catenin, in a non‑transcriptional manner. In the present study, the protein expression of CDX2 was analyzed, depending on the expression of the DNA repair proteins, mismatch repair (MMR), O6‑methylguanine DNA methyltransferase (MGMT) and excision repair cross‑complementing 1 (ERCC1), and its importance in Wnt signaling was also determined. A total of 101 liver metastases were punched into tissue microarray (TMA) blocks and serial sections were cut for immunohistochemistry. For each protein, an immunoreactive score was generated according to literature data and the scores were fitted to TMA. Subsequently, statistical analysis was performed to compare the levels of expression with each other and with clinical data. CDX2 loss of expression was observed in 38.5% of the CRC liver metastasis cases. A statistically significant association between CDX2 and each of the investigated MMRs was observed: MutL Homolog 1 (P<0.01), MutS protein Homolog (MSH) 2 (P<0.01), MSH6 (P<0.01), and postmeiotic segregation increased 2 (P=0.040). Furthermore, loss of MGMT and ERCC1 was also associated with CDX2 loss (P=0.039 and P<0.01, respectively). In addition, CDX2 and ERCC1 were inversely associated with metastatic tumor size (P=0.038 and P=0.027, respectively). Sustained CDX2 expression was associated with a higher expression of cytoplasmic/membranous β‑catenin and with nuclear APC expression (P=0.042 and P<0.01, respectively). In conclusion, CDX2 loss of expression was not a rare event in liver metastasis of CRC and the results suggested that CDX2 may be involved in mechanisms resulting in the loss of DNA repair protein expression, and in turn methylation; however, its exact function in this context remains to be elucidated. [ABSTRACT FROM AUTHOR]

Smoking tobacco is a known risk factor for the development of colorectal cancer and for mortality associated with the disease. Smoking has been reported to be associated with changes in DNA methylation in blood and in lung tumour tissues, although there has been scant investigation of how epigenetic factors may be implicated in the increased risk of developing colorectal cancer. To identify epigenetic changes associated with smoking behaviours, we performed epigenome-wide analysis of DNA methylation in colorectal tumours from 36 never-smokers, 47 former smokers, and 13 active smokers, and in adjacent mucosa from 49 never-smokers, 64 former smokers, and 18 active smokers. Our analyses identified 15 CpG sites within the APC 1A promoter that were significantly hypermethylated and 14 CpG loci within the NFATC1 gene body that were significantly hypomethylated ( pLIS < 1 × 10−5) in the tumours of active smokers. The APC 1A promoter was hypermethylated in 7 of 36 tumours from never-smokers (19%), 12 of 47 tumours from former smokers (26%), and 8 of 13 tumours from active smokers (62%). Promoter hypermethylation was positively associated with duration of smoking (Spearman rank correlation, ρ = 0.26, p = 0.03) and was confined to tumours, with hypermethylation never being observed in adjacent mucosa. Further analysis of adjacent mucosa revealed significant hypomethylation of four loci associated with the TNXB gene in tissue from active smokers. Our findings provide exploratory evidence for hypermethylation of the key tumour suppressor gene APC being implicated in smoking-associated colorectal carcinogenesis. Further work is required to establish the validity of our observations in independent cohorts. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Precision oncology implies the ability to predict which patients will likely respond to specific cancer therapies based on increasingly accurate, high-resolution molecular diagnostics as well as the functional and mechanistic understanding of individual tumors. While molecular stratification of patients can be achieved through different means, a promising approach is next-generation sequencing of tumor DNA and RNA, which can reveal genomic alterations that have immediate clinical implications. Furthermore, certain genetic alterations are shared across multiple histologic entities, raising the fundamental question of whether tumors should be treated by molecular profile and not tissue of origin. We here describe MASTER (Molecularly Aided Stratification for Tumor Eradication Research), a clinically applicable platform for prospective, biology-driven stratification of younger adults with advanced-stage cancer across all histologies and patients with rare tumors. We illustrate how a standardized workflow for selection and consenting of patients, sample processing, whole-exome/genome and RNA sequencing, bioinformatic analysis, rigorous validation of potentially actionable findings, and data evaluation by a dedicated molecular tumor board enables categorization of patients into different intervention baskets and formulation of evidence-based recommendations for clinical management. Critical next steps will be to increase the number of patients that can be offered comprehensive molecular analysis through collaborations and partnering, to explore ways in which additional technologies can aid in patient stratification and individualization of treatment, to stimulate clinically guided exploratory research projects, and to gradually move away from assessing the therapeutic activity of targeted interventions on a case-by-case basis toward controlled clinical trials of genomics-guided treatments. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is a highly aggressive brain tumor and still remains incurable. Among others, an immature subpopulation of self-renewing and therapy-resistant tumor cells-often referred to as glioblastoma stem-like cells (GSCs)-has been shown to contribute to disease recurrence. To target these cells personalized immunotherapy has gained a lot of interest, e.g. by reactivating pre-existing anti-tumor immune responses against GSC antigens. To identify T cell targets commonly presented by GSCs and their differentiated counterpart, we used a proteomics-based separation of GSC proteins in combination with a T cell activation assay. Altogether, 713 proteins were identified by LC-ESI-MS/MS mass spectrometry. After a thorough filtering process, 32 proteins were chosen for further analyses. Immunogenicity of corresponding peptides was tested ex vivo. A considerable number of these antigens induced T cell responses in GBM patients but not in healthy donors. Moreover, most of them were overexpressed in primary GBM and also highly expressed in recurrent GBM tissues. Interestingly, expression of the most frequent T cell target antigens could also be confirmed in quiescent, slow-cycling GSCs isolated in high purity by the DEPArray technology. Finally, for a subset of these T cell target antigens, an association between expression levels and higher T cell infiltration as well as an increased expression of positive immune modulators was observed. In summary, we identified novel immunogenic proteins, which frequently induce tumor-specific T cell responses in GBM patients and were also detected in vitro in therapy-resistant quiescent, slow-cycling GSCs. Stable expression of these T cell targets in primary and recurrent GBM support their suitability for future clinical use. [ABSTRACT FROM AUTHOR]

Red and processed meat is an established risk factor for colorectal cancer (CRC). However, exact mechanisms to explain the associations remain unclear. Few studies have investigated the association with CRC by molecular tumor features, which could provide relevant information on associated molecular pathways. In this population-based case-control study from Germany (DACHS), 2449 cases and 2479 controls provided information on risk factors of CRC and completed a food frequency questionnaire. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) for the associations between meat intake and risk of CRC by molecular pathologic features and specific subtypes. Red and processed meat intake was associated with increased risk of colorectal (>1 time/day vs ≤1 time/week OR 1.66, 95% CI 1.34-2.07), colon and rectal cancer. Among the single molecular tumor features investigated, the results were similar for associations of red and processed meat with CRC risk by microsatellite instability, CpG island methylator phenotype, BRAF, oestrogen receptor-β and p53 status. Red and processed meat intake was associated less strongly with risk of KRAS-mutated CRC (OR >1 time/day vs ≤1 time/week: 1.49, 95% CI 1.09-2.03) than with risk of KRAS-wildtype CRC (OR 1.82, 95% CI 1.42-2.34; p 0.04). These results support an association between red and processed meat and CRC risk similar for subsites of CRC and most of the investigated major molecular pathological features. Potential differences were observed in more specific subtype analyses. Further large studies are needed to confirm these results and to help further elucidate potential underlying mechanisms. [ABSTRACT FROM AUTHOR]

The chromatin remodeling switch sucrose nonfermentable (SWI/SNF) complex has been increasingly implicated in the pathogenesis and dedifferentiation of neoplasms from several organs with prognostic and potential therapeutic implications. We herein investigated the expression of the SWI/SNF complex catalytic subunits SMARCA4 (BRG1) and SMARCA2 (BRM) in 316 consecutive non-small cell lung cancer (NSCLC) specimens on tissue microarrays (171 adenocarcinomas [ADCAs], 130 squamous cell carcinomas [SCCs], 9 adenosquamous carcinomas, and 6 large cell carcinomas) excluding undifferentiated/giant cell or rhabdoid carcinomas. Complete loss of SMARCA4 was observed in 8 (5.5%) of 146 evaluable pulmonary ADCAs and 6 (5.2%) of 115 evaluable pulmonary SCCs, whereas 9 (6.4%) of 140 ADCAs and 2 (1.7%) of 117 SCCs showed SMARCA2 loss. Two of 6 large cell carcinomas were SMARCA2 deficient. Concurrent loss of both markers was observed in 4 cases (2 ADCAs and 2 SCCs). Of 15 ADCAs with loss of either or both markers, 12 (80%) were TTF1 negative. In conclusion, SMARCA4 and SMARCA2 deficiency is observed in 5.1% and 4.8% of NSCLC, respectively. SMARCB1 expression was intact in all cases. The presence of differentiated histology (glandular or squamous) is a novel aspect among SWI/SNF-deficient carcinomas which in other organs generally are associated with undifferentiated/rhabdoid morphology. The predominance of TTF1 negativity among SWI/SNF-deficient pulmonary ADCA (80%) underlines the need to include these 2 markers in the evaluation of TTF1-negative ADCA of putative pulmonary origin. Given the recently documented potential of SMARCA4 loss as a predictor of chemosensitivity to platinum-based chemotherapy in NSCLC, recognition of the clinicopathological features of SMARCA4-deficient NSCLC in routine surgical pathology practice is recommended. [ABSTRACT FROM AUTHOR]