Why does receptor tyrosine kinase (RTK) mutation in cancer cells increase resistance to apoptosis following chemotherapy?

💡 Explanation

RTK mutations often lead to constitutive activation of downstream survival signaling pathways like PI3K/Akt, because these pathways suppress pro-apoptotic protein expression, therefore cancer cells are more resistant to apoptosis signals, rather than directly enhancing caspase activation or upregulating pro-apoptotic proteins.

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