Effect of insulin on the mRNA expression of procollagen N-proteinases in chondrosarcoma OUMS-27 cells.

Abstract

Chondrosarcoma is one of the most common bone tumors, and at present, there is no non-invasive treatment option for this cancer. The chondrosarcoma OUMS-27 cell line produces proteoglycan and type II, IX, and XI collagens, which constitutes cartilage tissue. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) proteases are a group of secreted proteases, which include the procollagen N-proteinases ADAMTS-2, -3 and -14. These procollagen N-proteinases perform a role in the processing of procollagens to collagen and the maturation of type I collagen. The present study aimed to improve the understanding of the causes of metastasis, local invasion and resistance to chemo- and radiotherapy in chondrosarcoma, as well as the effect of insulin on cancer cells. The present study was designed to reveal the effects of insulin on procollagen N-proteinases in chondrosarcoma OUMS-27 cells. The cells were cultured in Dulbecco's modified Eagle's medium (DMEM) alone or in DMEM containing 10 µg/ml insulin. The medium was changed every other day for 11 days. The cells were harvested on days 1, 3, 7 and 11, and total RNA isolation was performed immediately following harvesting. The expression levels of ADAMTS2, ADAMTS3 and ADAMTS14 mRNA were estimated by reverse transcription-quantitative polymerase chain reaction using appropriate primers. ADAMTS2 mRNA expression was found to be decreased on day 7 (P=0.028) and increased at day 11 compared with the control group (P=0.016). The increase in mRNA concentration at day 11 was significantly different compared to the concentrations on days 3 (P=0.047) and 7 (P=0.008). The expression of ADAMTS3 mRNA decreased immediately subsequent to insulin induction on day 1 compared with the control group (P=0.008). The most evident decrease in mRNA concentration was seen at day 7 subsequent to insulin induction (P=0.008). The present results demonstrated that ADAMTS2 and ADAMTS3 may perform a role in the invasion and metastasis of tumors, and may also possess proteolytic activity that results in the breakdown of the extracellular matrix (ECM). Insulin itself can modulate the biosynthesis of ECM macromolecules that are altered in diabetes through various pathways.