is It possible that we loss apoptosis due to mutations in death receptor genes for example? or this is the only way found in humans regarding loss of apoptosis?
There are many many pathways that eventually induce or inhibit apoptosis. One example: tumours can have a Fas receptor mutation, so that they are resistant to FasL (ligand) secreted by cytotoxic T-cells, reducing or even preventing T-cell mediated killing. This can even be taken one step further: tumours start producing lots of FasL while having no Fas Receptor, thereby killing nearby T-cells trying to destroy the tumour.
