Investigation of TCEAL7 gene in colorectal cancer

Transcription factors play a key role in cancer development by changing expression levels of the oncogens and tumor suppressor genes. One of the transcription factors is TCEAL7 gene located in the q22.2 region of the X chromosome. TCEAL7 gene has been described in ovarian cancer and has been reported as a tumor suppressor gene. It has been shown that TCEAL7 gene has a role in glioblastoma, cervix, prostate, breast, stomach, brain and lung cancer. It is also known transcription factors has a role in colorectal carcinogenesis. The aim of this study was to investigate the possible effect of TCEAL7 gene in colorectal cancer. After RNA extraction, cDNA was obtained from tumors and normal tissues of 50 colorectal cancer patients. B2M was used for normalization to measure expression levels of TCEAL7 in tumor compared to normal tissue samples by using Real-Time PCR. The results were analyzed by 2-ΔΔCt method and 72% of tumor samples showed significantly low expression level for TCEAL7 gene. The Wilcoxon Signed Rank Test result was significant (p=0.000) and it was concluded that TCEAL7 gene is a tumor suppressor gene in colorectal cancer. According to Pearson's Chi-Square test, the expression level of TCEAL7 gene was not associated with clinical and pathological datas such as histological type and grade, TNM stage, age, gender, presence of invasion and tumor location by using. The results of the study indicate that TCEAL7 gene, has a tumor suppressor characteristic in colorectal cancer as previously shown in other cancer types. Further analysis should be done to enlighten the tumor suppressor function of TCEAL7 gene.