MLH1 Gene Expression in Peripheral Blood in Colon Cancer Patients and Their Association with Colon Cancer

Summary

This study examines the association between MLH1 gene expression in peripheral blood and colon cancer, utilizing a case-control approach to compare expression levels in patients and matched healthy controls.

Abstract

MutL homolog 1 (MLH1) is a component of the heterodimeric complex MutLα that detects and fixes base-base mismatches and insertion/deletion loops caused by nucleotide misincorporation. In the absence of MLH1 protein, the frequency of non-repaired mismatches increases, resulting in organ cancer. The current study sought to quantify MLH1 gene expression and its relationship with tumor invasion (T) and lymph node invasion (N) in blood samples from patients with colorectal cancer (CRC). Blood samples were obtained from 36 CRC patients. RNA was extracted, and cDNA was synthesized using a kit. The primers were built using the exon-exon junction approach, and MLH1 and β-actin genes were tested 3x using real-time polymerase chain reaction (Real-Time PCR). Gene expression analysis software was used to analyze the data, and a t-test was used to examine the expression of MLH1 and its connection with T and N variables. In this study, 36 patients with colorectal cancer, including 15 (41.6%) women and 21 (58.4%) men, with a mean age of 57.35 ± 4.22 years and in the age range of 26-87 years, were included. The results showed that the ratio of MLH1 gene expression in patients decreased compared to that in healthy individuals, and the decrease in gene expression at different stages of the disease was significant. The results of this study showed that the reduction of MLH1 gene expression has an effective role in the development of CRC.

Introduction

Colon cancer (CRC) is one of the most common types of cancer. It is the fourth leading cause of cancer-related death worldwide¹. CRC is more frequent in males than in females, and it is three to four times more common in industrialized countries than in developing countries. The age-standardized (global) incidence rate per 1 x 10⁵ of CRC incidences is 19.7 in both sexes, 23.6 in men, and 16.3 in females². Epidemiological studies have shown strong environmental and lifestyle associations with CRC. Obesity, red/processed meat, tobacco, alcohol, androgen deprivation therapy, and cholecystectomy are all assoc....

Protocol

A case-control research was conducted at Affiliated Hospital 2 of Nantong University between April 2021 and May 2023. Engage with the hospital's administrative department to establish the study framework. Ethical approval was obtained by submitting the study proposal to the Nantong University Ethics Committee. Ethical guidelines were followed to ensure confidentiality and informed consent.

1. Patient recruitment and study design

1. Sampling for inclusion of partic.......

Discussion

This study was conducted with the aim of investigating the expression of the MLH1 gene. In this study, it was shown that the level of MLH1 gene expression was decreased in sick people compared to healthy people. Based on fold change studies, it has been shown that the expression of the MLH1 gene in Stage II, Stage III, and Stage IV in sick people compared to healthy people had a significant decrease.

Colorectal cancer is a major problem in the management of cancer in.......

Materials

Name	Company	Catalog Number	Comments
Agarose Gel Electrophoresis Equipment	Bio-Rad	Mini-Sub Cell GT Systems	Used to check RNA quality
Ethylenediaminetetraacetic acid (EDTA)	Sigma-Aldrich	E9884	Used as an anticoagulant for blood samples
NanoDrop	ThermoFisher Scientific	ND-2000	Spectrophotometer used to determine RNA purity
Real-time PCR Machine	Applied Biosystems	A34322	Used for RT-PCR reactions
RNA Extraction Kit	Intron Biotechnology Co	#Cat 17061	Used for RNA extraction from blood samples
SYBR Green PCR Kit	Thermo Fisher Scientific	4309155	Reagents used for RT-PCR experiments