Quantitative measurement of iNOS expression in melanoma, nasopharyngeal, colorectal, and breast tumors of Tunisian patients: comparative study and clinical significance.

Chronic inflammation increases the risk of development of human malignancies. iNOS is an enzyme dominantly expressed during inflammatory reactions and seems to play a critical role in tumorigenesis. Our aim was to assess the iNOS expression in four types of human tumors: breast, colorectal, nasopharyngeal, and melanoma, of Tunisian patients.

Expression and mutation pattern of β-catenin and adenomatous polyposis coli in colorectal cancer patients.

Background And Aims: β-Catenin and adenomatous polyposis coli (APC) are major components of the Wnt pathway. This study aimed to investigate the expression of β-catenin and APC in tumors and lymph nodes in colorectal cancer (CRC) patients and the mutational spectrum of the genes coding these proteins.

Methods: Expression of APC and β-catenin was examined in 124 tumors and 41 lymph nodes.

Expression of p16INK4a, alone or combined with p53, is predictive of better prognosis in colorectal adenocarcinoma in Tunisian patients.

Introduction: Alterations in different signaling pathways are involved in initiation and progression of colorectal carcinoma, such as those related to p53, MLH1, p16INK4a, Kras, etc.

Aim: This study was conducted with the aim to investigate the expression of p16INK4a and p53 in colorectal cancer (CRC) and evaluated their correlation with major clinicopathologic features and patients' survival.

Materials And Methods: The expression of p16INK4a and p53 were analyzed by immunohistochemistry on 70 paraffin specimens of CRC.

Aberrant methylation of hMLH1 and p16INK4a in Tunisian patients with sporadic colorectal adenocarcinoma.

The methylation of CpG islands in the promoters is associated with loss of protein via repression of gene transcription. Several studies have demonstrated that tumour suppressor and DNA repair genes are often aberrantly hypermethylated in colorectal cancer. The present study was conducted to examine whether the methylation profile of p16INK4a and hMLH1 (human mutL homologue 1) promoters was associated with clinical features and patients' survival in CRC (colorectal carcinoma).

Hypermethylation of RARβ2 correlates with high COX-2 expression and poor prognosis in patients with colorectal carcinoma.

Silencing of gene expression by aberrant methylation at the CpG islands is common in human tumors, including colorectal cancer. This epigenetic alteration affects promoter of genes having crucial cellular functions such as tumor suppressor, DNA repair, apoptosis, cell adhesion, etc. We investigated the methylation status in the promoter regions of the RARβ2, RASSF1A, DAPKinase, and CDH1 genes in 73 colorectal carcinoma and 43 paired normal tissues of Tunisian patients using methylation-specific PCR assays.