Marlies S. Reimers

Expression of HLA Class I Antigen, Aspirin Use, and Survival After a Diagnosis of Colon Cancer

IMPORTANCE Use of aspirin (which inhibits platelet function) after a colon cancer diagnosis is associated with improved overall survival. Identifying predictive biomarkers of this effect could individualize therapy and decrease toxic effects. OBJECTIVE To demonstrate that survival benefit associated with low-dose aspirin use after a diagnosis of colorectal cancer might depend on HLA class I antigen expression. DESIGN, SETTING, AND PARTICIPANTS A cohort study with tumor blocks from 999 patients with colon cancer (surgically resected between 2002 and 2008), analyzed for HLA class I antigen and prostaglandin endoperoxide synthase 2 (PTGS2) expression using a tissue microarray. Mutation analysis of PIK3CA was also performed. Data on aspirin use after diagnosis were obtained from a prescription database. Parametric survival models with exponential (Poisson) distribution were used to model the survival. MAIN OUTCOMES AND MEASURES Overall survival. RESULTS The overall survival benefit associated with aspirin use after a diagnosis of colon cancer had an adjusted rate ratio (RR) of 0.53 (95% CI, 0.38-0.74; P < .001) when tumors expressed HLA class I antigen compared with an RR of 1.03 (0.66-1.61; P = .91) when HLA antigen expression was lost. The benefit of aspirin was similar for tumors with strong PTGS2 expression (0.68; 0.48-0.97; P = .03), weak PTGS2 expression (0.59; 0.38-0.97; P = .02), and wild-type PIK3CA tumors (0.55; 0.40-0.75; P < .001). No association was observed with mutated PIK3CA tumors (0.73; 0.33-1.63; P = .44). CONCLUSIONS AND RELEVANCE Contrary to the original hypothesis, aspirin use after colon cancer diagnosis was associated with improved survival if tumors expressed HLA class I antigen. Increased PTGS2 expression or the presence of mutated PIK3CA did not predict benefit from aspirin. HLA class I antigen might serve as a predictive biomarker for adjuvant aspirin therapy in colon cancer.

Biomarkers in precision therapy in colorectal cancer

Colorectal cancer (CRC) is the most commonly diagnosed cancer in Europe. Because CRC is also a major cause of cancer-related deaths worldwide, a lot of research has been focused on the discovery and development of biomarkers to improve the diagnostic process and to predict treatment outcomes. Up till now only a few biomarkers are recommended by expert panels. Current TNM criteria, however, cause substantial under- and overtreatment of CRC patients. Consequently, there is a growing need for new and efficient biomarkers to ensure optimal treatment allocation. An ideal biomarker should be easily translated into clinical practice, to identify patients who can be spared from treatment or benefit from therapy, ultimately resulting in precision medicine in the future. In this review we aim to provide an overview of a number of frequently studied biomarkers in CRC and, at the same time, we will emphasize the challenges and controversies that withhold the clinical introduction of these biomarkers. We will discuss both prognostic and predictive markers of chemotherapy, aspirin therapy as well as overall therapy toxicity. Currently, only mutant KRAS, mutant BRAF, MSI and the Oncotype DX® Colon Cancer Assay are used in clinical practice. Other biomarker studies showed insufficient evidence to be introduced into clinical practice. Divergent patient selection criteria, absence of validation studies and a large number of single biomarker studies are possibly responsible. We therefore recommend that future studies focus on combining key markers, rather than analysing single markers, standardizing study protocols, and validate the results in independent study cohorts, followed by prospective clinical trials.

The Prognostic Value of the Apoptosis Pathway in Colorectal Cancer: A Review of the Literature on Biomarkers Identified by Immunohistochemistry

Research towards biomarkers that predict patient outcome in colorectal cancer (CRC) is rapidly expanding. However, none of these biomarkers have been recommended by the American Association of Clinical Oncology or the European Group on Tumor Markers. Current staging criteria result in substantial under- and over-treatment of CRC patients. Evasion of apoptosis, a characteristic feature of tumorigenesis, is known to correlate with patient outcome. We reviewed the literature on immunohistochemistry-based studies between 1998 and 2011 describing biomarkers in this pathway in CRC and identified 26 markers. Most frequently described were p53, Bcl-2, survivin, and the Fas and TRAILR1 receptors and their ligands. None of the studies reviewed provided sufficient support for implementing a single marker into current clinical practice. This is likely due to the complex biology of this pathway. We suggest focusing on the combination of key markers within the apoptosis pathway that together represent an ‘apoptotic tumor profile’, which better reflects the status of this pathway in a tumor.

Clinical prognostic value of combined analysis of Aldh1, Survivin, and EpCAM expression in colorectal cancer

Background:Tumour aggressiveness might be related to the degree of main cancer hallmark acquirement of tumour cells, reflected by expression levels of specific biomarkers. We investigated the expression of Aldh1, Survivin, and EpCAM, together reflecting main cancer hallmarks, in relation to clinical outcome of colorectal cancer (CRC) patients.Methods:Immunohistochemistry was performed using a tumour tissue microarray of TNM (Tumour, Node, Metastasis)-stage I–IV CRC tissues. Single-marker expression or their combination was assessed for associations with the clinical outcome of CRC patients (N=309).Results:Increased expression of Aldh1 or Survivin, or decreased expression of EpCAM was each associated with poor clinical outcome, and was therefore identified as clinically unfavourable expression. Analyses of the combination of all three markers showed worse clinical outcome, specifically in colon cancer patients, with an increasing number of markers showing unfavourable expression. Hazard ratios ranged up to 8.3 for overall survival (P<0.001), 36.6 for disease-specific survival (P<0.001), and 27.1 for distant recurrence-free survival (P<0.001).Conclusions:Our data identified combined expression levels of Aldh1, Survivin, and EpCAM as strong independent prognostic factors, with high hazard ratios, for survival and tumour recurrence in colon cancer patients, and therefore reflect tumour aggressiveness.

Practical and Robust Identification of Molecular Subtypes in Colorectal Cancer by Immunohistochemistry.

Purpose: Recent transcriptomic analyses have identified four distinct molecular subtypes of colorectal cancer with evident clinical relevance. However, the requirement for sufficient quantities of bulk tumor and difficulties in obtaining high-quality genome-wide transcriptome data from formalin-fixed paraffin-embedded tissue are obstacles toward widespread adoption of this taxonomy. Here, we develop an immunohistochemistry-based classifier to validate the prognostic and predictive value of molecular colorectal cancer subtyping in a multicenter study. Experimental Design: Tissue microarrays from 1,076 patients with colorectal cancer from four different cohorts were stained for five markers (CDX2, FRMD6, HTR2B, ZEB1, and KER) by immunohistochemistry and assessed for microsatellite instability. An automated classification system was trained on one cohort using quantitative image analysis or semiquantitative pathologist scoring of the cores as input and applied to three independent clinical cohorts. Results: This classifier demonstrated 87% concordance with the gold-standard transcriptome-based classification. Application to three validation datasets confirmed the poor prognosis of the mesenchymal-like molecular colorectal cancer subtype. In addition, retrospective analysis demonstrated the benefit of adding cetuximab to bevacizumab and chemotherapy in patients with RAS wild-type metastatic cancers of the canonical epithelial-like subtypes. Conclusions: This study shows that a practical and robust immunohistochemical assay can be employed to identify molecular colorectal cancer subtypes and uncover subtype-specific therapeutic benefit. Finally, the described tool is available online for rapid classification of colorectal cancer samples, both in the format of an automated image analysis pipeline to score tumor core staining, and as a classifier based on semiquantitative pathology scoring. Clin Cancer Res; 23(2); 387–98. ©2016 AACR.

Prognostic value of HLA class I, HLA-E, HLA-G and Tregs in rectal cancer: a retrospective cohort study.

BackgroundEvasion of immune surveillance and suppression of the immune system are important hallmarks of tumorigenesis. The goal of this study was to establish distinct patterns that reflect a rectal tumors’ immune-phenotype and to determine their relation to patient outcome.MethodsThe study population consisted of 495 Stage I-IV non-preoperatively treated rectal cancer patients of which a tissue micro array (TMA) was available. Sections of this TMA were immunohistochemically stained and quantified for presence of Foxp3+ cells (Tregs) and tumor expression of HLA Class I and non-classical HLA-E and HLA-G. All markers were, separate and combined, analyzed for clinical prognostic value.ResultsExpression of HLA class I (DFS HR 0.637 (0.458-0.886), p = 0.013), Foxp3+ infiltration above median (OS HR 0.637 (0.500-0.813), p < 0.001 and DFS HR 0.624 (0.491-0.793), p < 0.001) and expression of HLA-G (DFS HR 0.753 (0.574-0.989), p = 0.042) were related to a better clinical prognosis. When these markers were combined, patients with 2 or 3 markers associated with poor prognosis (loss of HLA Class I, Foxp3+ below median, and weak HLA-G expression), showed a significantly worse survival (OS and DFS p < 0.001). This immune-phenotype was an independent predictor for DFS (HR 1.56 (1.14-2.14), p = 0.019).ConclusionsIn conclusion, rectal tumors showing loss of HLA class I expression, Foxp3+ infiltration below median and weak HLA-G expression were related to a worse OS and DFS. Combining these immune markers lead to the creation of tumor immune-phenotypes , which related to patient outcome and were significant independent clinical prognostic markers in rectal cancer.

Aspirin use after diagnosis improves survival in older adults with colon cancer: a retrospective cohort study.

To assess survival in relation to aspirin use after diagnosis in older adults with colon cancer.

Combined analysis of biomarkers of proliferation and apoptosis in colon cancer: an immunohistochemistry-based study using tissue microarray

BackgroundDisturbance of the balance between proliferation and apoptosis is an important hallmark of tumor development. The goal of this study was to develop a descriptive parameter that represents this imbalance and relate this parameter to clinical outcome in all four stages of colon cancer.Material and methodsThe study population consisted of 285 stage I–IV colon cancer patients of which a tumor tissue microarray (TMA) was available. TMA sections were immunohistochemically stained and quantified for the presence of Ki67 and cleaved caspase-3 tumor expression. These results were used to develop the combined apoptosis proliferation (CAP) parameter and correlated to patient outcome.ResultsThe CAP parameter was significantly related to clinical outcome; patients with CAP ++ (high level of both apoptosis and proliferation) showed the best outcome perspectives (overall survival (OS), p = 0.004 and disease-free survival (DFS), p = 0.009). The effect of the CAP parameter was related to tumor microsatellite status and indirectly to tumor location, where left-sided tumors with CAP + − (high level of proliferation, low level of apoptosis) showed a worse prognosis (DFS p value 0.02) and right-sided tumors with CAP + − had a better prognosis (DFS p value 0.032). With stratified analyses, the CAP parameter remained significant in stage II tumors only.ConclusionsThe CAP parameter, representing outcome of the balance between the level of apoptosis and proliferation, can be used as a prognostic marker in colon cancer patients for both DFS and OS, particularly in left-sided, microsatellite stable tumors when tumor–node–metastasis (TNM) stage is taken into account.

How does genome sequencing impact surgery

Cancer is a leading cause of death worldwide. Great efforts are dedicated to the development of prognostic and predictive biomarkers to improve diagnosis and achieve optimal treatment selection, thereby, introducing precision medicine in the multimodality treatment of cancer. Genomic aberrations are the basis of tumour development, representing excellent candidates for the development of promising clinical biomarkers. Over the past decade, single-gene mutations and genomic profiling have been increasingly used in multidisciplinary consultations for risk-assessment and treatment planning for patients with cancer. We discuss the impact of such genetic-based information on surgical decision-making. Single-gene mutations have already influenced surgical decision-making in breast, colorectal and thyroid cancer. However, the direct impact of genomic profiling on surgical care has not yet been fully established. We discuss the direct and indirect influences of genomic profiling on surgery, and analyse the limitations and unresolved issues of a genotypic-approach to the surgical management of cancer.

Tu1976 Statin Use After Diagnosis Improves Survival in Colorectal Cancer Patients

Background: The use of statins has been associated with a reduced incidence of colorectal cancer. Potentially, statins may also have an influence on survival of colon cancer patients when used after diagnosis. The primary aim of this observational study was to evaluate the influence of statin use after diagnosis of colon cancer on overall survival. The secondary aim was to investigate the molecular background in which statins are effective adjuvant therapeutic agents, specifically KRAS mutational status and Bone Morphogenetic Protein pathway functionality, as these are the two most promising and frequently mentioned potential molecular mechanisms. Methods: Data was derived from the PHARMO database network (PHARMO, Netherlands) and was linked to a colon cancer cohort (Eindhoven Cancer Registry). A Tissue Micro Array (TMA) consisting of 999 colon cancer specimens was constructed from patients who had a surgical resection between 2002 and 2008. Survival was analyzed with statin user status after diagnosis as a time-dependent covariate. Multivariate Poisson regression survival models were used to study the effect of statins on overall survival (OS). The tumors were analyzed for SMAD4, BMPR1a, BMPR1b and BMPR2 expression, and KRAS mutations to perform stratified analyses for intact BMP signaling status and KRAS mutation status. Results: In this cohort 21.0% (210/999) of the patients were defined as statin users after colon cancer diagnosis. Statin use after diagnosis was significantly associated with an improved OS with an adjusted Rate Ratio (RR) of 0.67 (95% CI 0.51-0.87, P= 0.003). When stratified for intact BMP signaling status, survival benefit of statin use after diagnosis was stronger in tumors with intact BMP signaling (adjusted RR 0.46 (95% CI 0.29-0.74, P=0.001) than in tumors with a non-intact BMP signaling pathway (adjusted RR 0.75, 95% CI 0.53-1.06, P=0.106). Statin use after diagnosis was not associated with an improved OS in KRAS wild-type tumors (Adjusted RR 0.81, 95% CI 0.56-1.18, P=0.273) or KRAS mutated-tumors (Adjusted RR 0.59, 95% CI 0.35-1.03, P=0.062). Conclusion: Statin use after diagnosis is associated with an improved overall survival in colon cancer patients. This survival benefit is more prominent in tumors with intact BMP signaling. The survival benefit is independent of KRAS mutation status.