Additional prognostic factors in right colon cancer staging

Targeting estrogen receptors in colorectal cancer

Hormones have become a useful therapeutic aspect of clinical endocrinology but how to use them to optimize the health benefits and avoid adverse effects is a major challenge. Estrogen is an indispensable hormone for proper biological functioning but is also implicated with the pathology of both the reproductive and non-reproductive tissues. Abnormal estrogen receptor signaling may increase the risk of development of a variety of diseases including colorectal cancer (CRC). Estrogen receptor beta (ERβ) is the predominant subtype in the colonic epithelium and confers the anti-tumor effect through various mechanisms. Many investigators have embarked on the search for the biological mechanisms by which estrogen and estrogen-like compounds may influence the pathogenesis of CRC. This review explores the recent findings on the therapeutic role of ERβ in the colonic epithelium as a prospective candidate for targeted endocrine therapy in CRC.

The role of neurotensin as a novel biomarker in the endoscopic screening of high-risk population for developing colorectal neoplasia

Colorectal cancer screening programs aim at early detection of cancer to reduce incidence rates and mortality. The objective of this study is to identify the role of neurotensin in the endoscopic screening of high-risk population for developing colorectal neoplasia. Blood samples from patients referred for urgent colonoscopy to investigate symptoms suspicious of colorectal cancer were collected. Blood neurotensin levels were measured using enzyme-linked immunosorbent assay. Colonoscopy findings were used as reference for determining the diagnostic accuracy of blood neurotensin. The study comprised 26 patients in total: 12 healthy and 14 with colon pathology (13 high-grade dysplasia adenomatous polyps, 1 adenocarcinoma). There were no statistically significant differences in the clinical and biochemical parameters between colon pathology and healthy group except neurotensin levels. Pathology in colon was associated with 3.7-fold increase in NT levels. In multivariate analysis, patients with pathology in colon have increased serum neurotensin levels compared to controls adjusted for age, gender, BMI and co-morbidities. The value of 12.93 pg/ml is associated with 87.5% sensitivity and 91.7% specificity for discriminating the colon pathology from normal colonic epithelium (p = 0.001). Neurotensin plasma values differentiate healthy people from patients suffering from colonic pathologies such as adenomatous polyps and cancer. The use of neurotensin as a potential endoscopic screening tool for identifying high-risk population for developing colorectal cancer is promising, but much has to be done before it is validated in larger scale prospective studies.

Estrogen receptors and their implications in colorectal carcinogenesis

Upon binding their cognate receptors, ERα (ESR1) and ERβ (ESR2), estrogens activate intracellular signaling cascades that have important consequences for cellular behavior. Historically linked to carcinogenesis in reproductive organs, estrogens have also been implicated in the pathogenesis of different cancer types of non-reproductive tissues including the colon. ERβ is the predominant estrogen receptor expressed in both normal and malignant colonic epithelium. However, during colon cancer progression, ERβ expression is lost, suggesting that estrogen signaling may play a role in disease progression. Estrogens may in fact exert an anti-tumor effect through selective activation of pro-apoptotic signaling mediated by ERβ, inhibition of inflammatory signals and modulation of the tumor microenvironment. In this review, we analyze the estrogen pathway as a possible therapeutic avenue in colorectal cancer, we report the most recent experimental evidence to explain the cellular and molecular mechanisms of estrogen-mediated protection against colorectal tumorigenesis, and we discuss future challenges and potential avenues for targeted therapy.