Expression of angiotensin converting enzyme 2 in patients with oral squamous cell carcinoma

Abstract

BackgroundOral squamous cell carcinoma (OSCC), being a multifactorial cancer, is significantly higher in South Asian countries and only 70 % of the cases are reported only in its advanced stages. As a component of the renin-angiotensin system (RAS), Angiotensin-Converting Enzyme 2 (ACE2) has been reported to restrain the progression of hepatocellular carcinoma (HCC) and non-small cell lung cancer (NSCLC) by inhibiting angiogenesis, nevertheless the role of ACE 2 in Oral Squamous Cell Carcinoma progression remains unexplored. ObjectiveTo quantify and compare tissue expression levels of Angiotensin Converting Enzyme 2 in patients with oral squamous cell carcinoma and healthy individuals. Materials and methodsThe current study was a case-control study, that includes n = 10 Oral Squamous Cell Carcinoma samples and n = 10, non-pathological tissues taken from healthy subjects, as controls. Fresh tissue samples were collected from the primary tumor areas of OSCC patients and healthy tissue samples from patients who had tooth extraction, and both tissues were stored at −80 °C. RNA isolation was performed using the TRIR kit from Invitrogen. cDNA was synthesized from total RNA isolated from tissues using a first-strand synthesis kit. Finally, ACE2 was assayed using an ultrasensitive human-specific ELISA kit. Statistical analysis was done using independent T test. ResultsThe data were expressed as mean ± standard deviation and the statistical analysis was done.OSCC patients showed ACE 2 mean optical density of 0.37 with SD ± 0.045 and healthy individuals showed a mean optical density of 0.45 with SD ± 0.052. The mean ng/L scores of OSCC and healthy individuals were 13.57 with SD ± 1.65 and 16.2 with SD ± 1.9 respectively. Optical density and concentration ng/L scores were compared between OSCC samples, showed a minimum value of 0.137 and a maximum of 2.253. Analyzed results shows that the ACE 2 protein expression in OSCC tumour tissue was lower than that in normal tissue (p = 0.004) ConclusionAngiotensin Converting Enzyme 2 was significantly lower in Oral Squamous Cell Carcinoma tissues when compared with healthy samples. However, further validation in large-scale prospective studies is necessary to explore the role of ACE 2 in prognosis of OSCC.