Apoptotic Activities in Soft Tissue Sarcoma: Immunohistochemical Study and Their Association with Tumour Characteristics

ABSTRACT

Background: Many studies on the role of apoptosis in cancer development and management have been undertaken. Apoptotic activity depends partly on the balance between anti-apoptotic (Bcl-2) and pro-apoptotic (Bax) activities. This study compared Bcl-2 and Bax expression in the tumour cells and endothelial cells of tumour blood vessels in soft tissue sarcoma, and examined the association of these with tumour characteristics. Methods: A cross sectional (retrospective) study was conducted on 101 cases of various types of soft tissue sarcoma tumour cells and endothelial cells of tumour blood vessels. The immunohistochemical expressions of Bcl-2 and Bax were compared by correlating them according to site, size, depth, tumour margin, lymph node involvement, and histological type. Results: Higher Bax than Bcl-2 expression in tumour cells was observed, although the difference was not statistically significant. There was a significant direct association between Bcl-2 and Bax in tumour cells with endothelial cells. Among tumour characteristics, the only significant correlation was that of the Bcl-2 expression in tumour cells with tumour histological subtypes (synovial sarcoma and leiomyosarcoma). Conclusion: The findings in this study support the role of endothelial cells in the survival and regression of tumour cells in tumour genesis. Therefore, inhibition of endothelial cell survival and activation, or induction of tumour cell apoptosis offers a promising prospect for tumour management.