Differences of protein expression profiles, KRAS and BRAF mutation, and prognosis in right-sided colon, left-sided colon and rectal cancer

Abstract

To compare protein expression levels, gene mutation and survival among Right-Sided Colon Cancer (RSCC), Left-Sided Colon Cancer (LSCC) and rectal cancer patients, 57 cases of RSCC, 87 LSCC and 145 rectal cancer patients were included retrospectively. Our results demonstrated significant differences existed among RSCC, LSCC and rectal cancer regarding tumor diameter, differentiation, invasion depth and TNM stage. No significant difference was identified in expression levels of MLH1, MSH2, MSH6, PMS2, β-Tubulin III, P53, Ki67 and TOPIIα, and gene mutation of KRAS and BRAF among three groups. Progression Free Survival (PFS) of RSCC was significantly lower than that of LRCC and rectal cancer. In univariate analyses, RSCC, preoperative chemoradiotherapy, poor differentiation, advanced TNM stage, elevated serum CEA and CA19-9 level, tumor deposit, perineural and vascular invasion were found to be predictive factors of shorter PFS. In multivariate analyses, only differentiation and TNM stages were found to be independent predictors of PFS. In conclusion, compared with LSCC and rectal cancer, RSCC has larger tumor size, poor differentiation, advanced TNM stage and shorter survival. The shorter survival in RSCC might be attributed to the advanced tumor stage caused by its inherent position feature of proximal colon rather than genetic difference.

Influence of primary tumour and patient factors on survival in patients undergoing curative resection and treatment for liver metastases from colorectal cancer

“…Patients with right-sided tumours have longer recurrence-free survival than those with left-sided tumours, but at recurrence the course of the disease seems to be more complicated with shorter OS 30 . The right colon, evolving from the mid gut, and the left colon, evolving from the hind gut, are physiologically distinct and may also differ in genetic and immunopathological characteristics 32,33 . The right colon, evolving from the mid gut, and the left colon, evolving from the hind gut, are physiologically distinct and may also differ in genetic and immunopathological characteristics 32,33 .…”

Screening and Identification of Differentially Expressed Genes Expressed among Left and Right Colon Adenocarcinoma

“…RCOAD is related to KRas and Serine/ threonine-protein kinase B-raf (BRAF) mutations of defect mismatch repair genes and microRNA-31, while LCOAD is closely associated with chromosome instability, p53, NRas, and microRNA-146a, microRNA-147b, and microRNA-1288 [10]. However, Gao et al [11] showed no significant difference in the expression levels of MLH1, MSH2, MSH6, PMS2, β-tubulin III, p53, Ki67, topoisomerase Iiα, and BRAF gene mutations between the two types of COAD. A number of studies have reported significant differences in p53 gene mutation and protein expression between RCOAD and LCOAD [12][13][14], while another study has shown no significant correlation between p53 protein expression and tumor location [15].…”

Comparative mutational analysis of distal colon cancer with rectal cancer

“…Therefore, traditionally, patients with distal colon and rectal cancer have frequently been grouped together in clinical or scientific research. However, there is increasing evidence that distal colon and rectal cancer are related to each other but are distinct in regard to their clinical behavior, including the patterns of metastasis, response to treatment and clinical outcome (5)(6)(7). However, to the best of our knowledge, the underlying biological carcinogenic backgrounds of the two types of cancer have not been investigated.…”