Investigation of the expression levels of some genes in different stage colorectal tumors

Colorectal cancer is one of the most observed cancers. It is a major health problem with an estimated 1.8 million new cases worldwide. Colorectal cancer is defined by cancerous growths colon, rectum and/or subsequent. The source of colorectal cancer is a small benign tumor or polyp called adenoma in the colorectal epithelium, which gradually grows into an malignant phenotype, gradually becoming more irregular in its intracellular organization. It is well known that various gene expression differences can be detected during colon cancer development. On the basis of all genome expression studies, it is intended to identify clinically useful biomarkers and then be developed and used as part of routine diagnosis in tumor classification. In our study, the mRNA levels of the CPEB4, APC, TRIP13, EIF2S3, EIF4A, IF, PIK3CA and CTNNB1 genes were determined in tumor tissues and peripheral blood samples of 45 patients with colorectal cancer and colon tissues belonging to 5 healthy individuals and peripheral blood samples. Real Time Polymerase Chain Reaction method was used for the analysis. The results were evaluated with the REST 2009 software program. In our study, the mRNA level of the CPEB4 gene was significantly down regulated in all colorectal tumor tissues relative to the controls (P0,05), while it was significantly up regulated in the peripheral blood of patients with colorectal cancer (P0,05). When compared in terms of stages, up regulation was important in stage I and stage II in peripheral blood (P0,05) while down regulation was important in stage I tumor tissues (P0,001). The mRNA level of the APC gene was significantly down regulated in all colorectal tumor tissues relative to the controls (P0,05), while it was significantly up regulated in the peripheral blood of patients with colorectal cancer (P0,05). When comparing in terms of stages, up regulation was important in Stage III peripheral blood (P0,05), while down regulation was important in stage IV tumor tissues (P0,05). TRIP13 mRNA level was significantly up regulated in both colorectal tumor tissues and peripheral blood relative to the controls (P0,05). Especially this up regulation is important in stages I-II and III in peripheral blood (P0,05). EIF2S3 mRNA level was up regulated in both colorectal tumor tissues and peripheral blood relative to the controls. This up regulation is important only for EIF2S3 mRNA expressed in peripheral blood (P0.05). This up regulation is also important in stage I and III peripheral blood (P0.05). While, PIK3CA mRNA level was down regulated in colorectal tumor tissues relative to the controls, it was up regulated in peripheral blood. However, these changes are not important (P0,05). While EIF4A1 mRNA level was down regulated relative to controls in colorectal tumor tissues (P0.05), it was up regulated in peripheral blood (P0.05). This up regulation was important in peripheral blood stages I and III (P0.05). CTNNB1 mRNA level was down regulated in tumor tissues relative to the controls (P0,05), while it was up regulated in peripheral blood (P0,05). Especially it was down regulated in Stage I colorectal cancer tissues (P0.05), while it was upregulated in Stage I peripheral blood (P0.05). IF mRNA level was up regulated in both colorectal cancer tumor tissues and peripheral blood relative to the control. However, this up regulation was not important. When evaluated in terms of stages, different results were observed in mRNA levels. In general, when our results are evaluated and compared with the literature, we think that TRIP13 and CPEB4 mRNA up regulation in the peripheral blood of patients with colorectal cancer may be a potential target for early stage diagnosis. In addition to this evaluation, although there is not much study on EIF2S3 and EIF4A1 mRNA changes in cases with colorectal cancer, upregulation in peripheral blood draws attention in our study. These data will shed light on the these data will shed light on the new comprehensive studies. Keywords: Biomarker, colorectal tumor, different stage, gene expression.