Expression analysis of PTEN and CDKN1C/p57kip2 in cancerous tissues from Iranian patients with gastric cancer

Abstract

Background: Since gastric cancer (GC) is the third prevalence cause of cancer-related death, early diagnosis can improve survival rate. Some studies indicated that loss of tumor suppressor gene (TSG) is a key event in gastric carcinoma. Based on epigenetic alteration each population is valuable to evaluate. So this study investigated the expression rate of phosphatase and tensin homolog (PTEN) and a cyclin-dependent kinase inhibitor of G1 cyclin complexes (CDKN1C) in a population in Iran. Methods: 64 gastric samples (32 tumoral gastric tissues and 32 healthy adjacent tissues) were collected from patients referred to Imam Khomeini Hospital Cancer Institute during 2008-2011. Total RNA was extracted, cDNA was synthesized, and then expression level of PTEN and CDKN1C was detected by Real time-PCR. Results: Our results displayed PTEN and CDKN1C expression significantly decreased in cancerous tissues compared to healthy adjacent tissues (P<0.05). In the case of PTEN, ΔΔCT was calculated 3.04 that showed 8.2 times expression reduction in tumorous tissues. Also, the ΔΔCT of CDKN1C was 2.6 which represents 6.1 times expression reduction in tumorous samples. Furthermore, there is an association between PTEN and CDKN1C expression and vascular invasion. However, the study of parameters such as age, tumor size, sex, ethnicity, and stage were not significantly associated with decreased expression of these TSGs. Conclusion: A significant expression reduction of both TSGs in tumoral tissues compared with healthy adjacent tissues suggest that these genes have an important role in gastric cancer incidence and future researches may reveal their advantage in treatment and diagnosis.