Alterations of Tumor Suppressor Genes Expression in Colorectal Cancer: Their Impact on Progression and Prediction of Patients Outcome
Menha Swellam *
Genetic Engineering and Biotechnology Research Division, Department of Biochemistry, National Research Centre, Dokki, Giza, Egypt and High Throughput Molecular and Genetic laboratory, Center for Excellences for Advanced Sciences, National Research Centre, Dokki, Giza, Egypt
Tamer E. Mosa
Genetic Engineering and Biotechnology Research Division, Department of Biochemistry, National Research Centre, Dokki, Giza, Egypt
Mie Afify
Genetic Engineering and Biotechnology Research Division, Department of Biochemistry, National Research Centre, Dokki, Giza, Egypt
Mohamed D. E. Abdelmaksoud
Genetic Engineering and Biotechnology Research Division, Department of Biochemistry, National Research Centre, Dokki, Giza, Egypt
Lobna R. Ezz El Arab
Department of Clinical Oncology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
*Author to whom correspondence should be addressed.
Abstract
Background: Deregulation of tumor suppressor genes as APC, DCC and SMAD2 are related to tumorgenesis thus we aimed to investigate their expression among colorectal cancer to validate their relation with clinicopathological factors and the clinical outcome for CRC patients.
Materials and Methods: Formalin-fixed paraffin samples from 115 colorectal cancer were investigated for APC, DCC and SMAD2 gene expression using quantitative PCR (QPCR) and their levels were analyzed versus clinicopathological factors and the overall survival (OS) of colorectal cancer patients.
Results: A significant relation was reported between DCC and SMAD2 gene expression with clinical stages as they reported decrease expression among those with stage III. The three investigated genes were decreased significantly with poor histological differentiation colorectal cancer patients. The correlations between the expressions of the investigated genes revealed a significant correlation between SMAD2 and APC as well as between SMAD2 and DCC. Moreover patients with mean levels below and equal their expression values showed a considerable difference with OS.
Conclusion: Gene expression of tumor suppressor genes APC, DCC and SMAD2 were significantly related to differential grading and patient's outcome thus pointing out their potential role as predictive markers for prognosis of colorectal cancer.
Keywords: Tumor suppressor genes, colorectal cancer, APC, DCC, SMAD2, progression, prediction