Inhibiting metastatic potential: an analysis of migratory body formation in chondrosarcoma

Chondrosarcoma (CHS) is the 2nd most prevalent bone sarcoma. Approximately 27% of all bone cancer cases reported to the International Agency for Research on Cancer (IARC) database are CHS. CHS tends to primarily affect adults above the age of 30 with 70% of cases reported affecting patients of 40 years and above. While CHS has an optimistic 5-year survival rate of 75.2%, this can depend greatly on the accuracy and time of diagnosis, histological grade, and subtype. Metastasis which often leads to chemoresistance have been primary complications in this cancer which often leave minimal treatment options, prolong the treatment course, and cause severe damage to the patients’ quality of life.

In our research group, we have identified a potential route through which metastasis might occur. Our in vitro observations with CHS cell-line SW1353 have shown that spheroids which we call migratory bodies (MB) can detach from the monolayer in our cell culture plates and remain suspended in the media. These MBs have shown to be able to adhere and proliferate, forming new colonies once replated into a fresh cell culture plate. Different cell seeding densities were used in 6 well-plates to optimise the production of MBs. 5000 cells/cm2 was found to be the optimum seeding density to produce the maximum number of MBs in SW1353. EGF and FGF were used to further optimise the formation of these MBs. A combined dose of 10ng/ml EGF and 10ng/ml FGF was shown to maximise the production of MBs. Human osteoclasts were cultured from isolated PBMCs. When 20% media used for culturing osteoclast was introduced to SW1353 with optimum seeding density and optimum dose of growth factor, a significant downstream effect was observed in the production of MBs, suggesting the presence of factors in osteoclast conditioned media with the potential to inhibit metastasis in chondrosarcoma.