Smoking and Brain Neoplasm: An Immunohistochemical Data Evaluating Caspase-۳ and MMP-۲ in Rat Brain

Background and Aim: Smoking has been extensively investigated in oncology, and controversial associations with brain tumor incidence have been reported. Caspase-۳ and matrix metalloproteinases (MMPs) belong to an important cascade in tumor vasculogenesis. We aim to study the smoking impact on these signaling molecules in nontumoral rat brain tissue. Methods and Materials: A total of ۶۰ Wistar rats were divided into two groups: treatment (cigarette smoke/electronic cigarette) and control groups with subgroups of male and female rats. After general anesthesia and decapitation, their brains were collected, and ۳-μm thick coronal sections were prepared. Following immunohistochemical staining with rabbit anti-MMP-۲ and anti-caspase-۳ antigens, protein expressions were analyzed by selecting two fields at ۴۰۰x magnification. Results: Our data suggest that the expression of MMP-۲ was not significantly different between the studied groups. However, the significant inductive activity of cigarette smoking was observed on caspase-۳. Conclusion: Cigarette smoking indicates pro-tumoral signaling impact in normal tissue with activation of caspase-۳ in rat brain tissue.