CASP9 and breast cancer: However, another study showed that exendin 4 exerted anticancer effects by promoting apoptosis and inhibiting the growth of MCF-7 BC cells [85], and exendin 4 reduced the expression of Akt, caspase 9 and metalloproteinase 2, whereas it increased the expression of caspases 3, 8 and 10, p53, phosphatase and tensin homolog (PTEN), tissue inhibitor of metalloproteinase (TIMP) 1 and 2, and poly-ADP ribose polymerase (PARP) in MCF-7 BC cells [85].