- CD99 isoforms dictate opposite functions in tumour malignancy and metastases by activating or repressing c-Src kinase activity. Scotlandi, K., Zuntini, M., Manara, M.C., Sciandra, M., Rocchi, A., Benini, S., Nicoletti, G., Bernard, G., Nanni, P., Lollini, P.L., Bernard, A., Picci, P. Oncogene (2007)