Commonly used metallic biomaterials may be involved in cancer processes – in vitro studies

There are reports available in the literature describing neoplastic changes around implants or at distant sites that temporally correlate with implantation, although they are not supported by sufficient clinical evidence. Such reports mainly concern the implantation of dental implants, which are performed in the largest number, and squamous cell carcinoma is one of the main types of cancer located in the vicinity of such implants. The occurrence of malignancies after hip arthroplasty has also been described in the vicinity of endoprostheses. At present, there are no indisputable data on the promotion of carcinogenesis by the implants used, and the problem of accelerated tumour induction in the area of implantation is still poorly understood and unclear. The aim of the study was a preliminary assessment of changes in the physiological processes of cells induced by metallic biomaterials intended for orthopaedic implants. A preliminary assessment of changes in the expression of cancer-promoting genes in chondrocytes exposed to metallic biomaterials was recently published. The current report is an analytical summary of changes in proliferation potential, DNA damage repair activity, and apoptosis level of primary and neoplastic cells (chondrocytes and osteoblasts) exposed to commonly used metallic biomaterials (AISI 316L, Ti6Al4V, Ti6Al7Nb, and CoCrMo). Immunofluorescence labelling techniques in flow cytometry were used for the study. The results obtained allow us to state that short-term (48 h) direct exposure to metallic biomaterials of osteoblasts and chondrocytes, both primary and cancerous, can cause significant changes in cell physiology, which may result in promoting the cancer process.