Transcriptional profiles underpin microsatellite status and associated features in colon cancer.

Introduction: While microsatellite instability is associated with prognosis and distinct clinical phenotypes in colon cancer, the basis for this remains incompletely defined. Novel bioinformatic techniques enable a detailed interrogation of the relationship between gene expression profiles and tumor characteristics.

Aim: We aimed to determine if microsatellite instability high (MSI-H) and microsatellite stable (MSS) tumors could be differentiated by gene expression profiles.

High-throughput arrays identify distinct genetic profiles associated with lymph node involvement in rectal cancer.

Background: Preoperative clinical diagnosis of lymph node involvement guides treatment decisions for rectal cancer. Unfortunately, clinical staging still suffers from a lack of accuracy.

Objective: The aim of this study was to evaluate objective genetic differences in primary rectal cancers with and without associated lymph node metastasis.

BRAF mutations in colorectal cancer are associated with distinct clinical characteristics and worse prognosis.

Background: Colorectal cancer is a heterogeneous disease with multiple underlying genetic mutations causing different clinical phenotypes. Mutation in the BRAF oncogene is a key step in malignant transformation within the methylator pathway to colorectal cancer. However, there is a paucity of information about BRAF mutant colorectal tumors.

Relative role of methylator and tumor suppressor pathways in ulcerative colitis-associated colon cancer.

Background: Chronic ulcerative colitis (UC) is associated with an increased colorectal cancer risk which may be secondary to repetitive mucosal injury. Both epigenetic methylation and the classic adenoma-to-carcinoma sequence have been implicated in this malignant transformation, but the underlying molecular mechanisms remain poorly defined. This study compares the molecular characteristics of colitis-associated and common colorectal cancers.

Gene signature is associated with early stage rectal cancer recurrence.

Background: Despite expected excellent outcomes of surgical resection for early stage rectal cancers, 20% of stage I and II rectal cancers recur. Identifying biologic factors that predict the subset prone to recur could allow more directed therapy. This study identifies a tumor gene expression profile that accurately predicts disease recurrence.

CEACAM-7: a predictive marker for rectal cancer recurrence.

Background: The identification of rectal cancer patients predisposed to developing recurrent disease could allow directed adjuvant therapy to improve outcomes while decreasing unnecessary morbidity. This study evaluates carcinoembryonic antigen cellular adhesion molecule-7 (CEACAM-7) expression in rectal cancer as a predictive recurrence factor.

Methods: A single-institution colorectal cancer database and a frozen tissue biobank were queried for rectal cancer patients.

Genetic and molecular diversity of colon cancer hepatic metastases.

Background: Colon cancer arises through distinct molecular pathways resulting in diverse tumor populations demonstrated by differences in microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and mutations in oncogenes KRAS and BRAF. Although these molecular differences are well-described for primary neoplasms, the molecular nature of hepatic metastases is not well-characterized. This study seeks to describe molecular characteristics of colon cancer hepatic metastases in terms of oncogenic pathway.