Any tumour cell submitted to an inadequate/abnormal environment (highly proliferative cells in an environment with limited and constant netrin-1 concentration, migration to other tissues because of metastatic propensities) would display unbound dependence receptors, thus triggering the proapoptotic activity of DCC and/or UNC5H, which would ultimately lead to cell death and subsequent tumour regression. The gene discussed is DCC; the disease is neoplasm.