May metallic biomaterials used for orthopaedic implants promote carcinogenesis? Preliminary transcriptomic research on human chondrocytes

The aim of this research was to assess the risk of carcinogenesis induced by the metallic materials intended for orthopaedic implants. The report is an analytical summary of changes in the expression of cancer-related genes in human chondrocytes of normal and neoplastic phenotype. Cq values (quantification cycle values) obtained from qRT-PCR reactions (quantitative real-time polymerase chain reactions) were used to count Fc values (fold change values) for each gene. Differences in Fc values obtained for primary and cancer cells grown on the surface of medical steel AISI316L and titanium-aluminum-vanadium alloy Ti6Al4V were then analyzed by t-Student test. The results indicate that for cancer cells grown on the surfaces of both examined materials the fold change greater than 2, usually considered essential, was found for LUM gene involved in sarcoma induction. For FOS gene, also involved in sarcoma induction, the Fc value was also very close to 2 in the primary cells exposed to Ti6Al4V alloy. The remaining observed changes were rather subtle, although they cannot be omitted from further studies because differences in gene expression in primary and tumor cells grown on the same biomaterial were statistically significant in several cases. The compilation of qRT-PCR experiments carried out on primary and cancer cells in parallel allowed to identify possible future contraindications for patients with a genetic predisposition to cancer or with cancer history.