Expression of interleukin-6 (IL-6), signal transducer and activator of transcription-3 (STAT-3) and telomerase in choriocarcinomas

Blastocyst implantation and neoplastic invasion have some common properties related to tissue invasion, mediated by various cytokines. Aim To compare the expression of IL-6, STAT-3 and telomerase in material of abortions in the first trimester of pregnancy, at term placentas and in choriocarcinomas. Methods Immunohistochemical reactions were performed on formalin fixed and included in paraffin samples from 3 groups: abortions, normal at term placentas and choriocarcinomas. Western Blot and Real-Time PCR assays were performed on fresh material from BeWo cell line and in primary culture cells of normal placenta. Results Immunohistochemical reactions: IL-6 expression was moderate in the first trimester abortion samples and high in at term placentas and choriocarcinomas. STAT-3 was strongly positive in all groups. Telomerase expression was absent in normal at term placentas but was increased in BeWo cells. Conclusion IL-6 and STAT-3 are present in the invasion process of the normal placental development and they are maintained during the malignant transformation to choriocarcinoma. The intense telomerase expression observed in BeWo cells was strongly associated with the malignant phenotype, confirming it as a good marker for cell transformation and tumor progression.