KRAS and cancer: Interestingly, a recent study found that activated PI3K signalling could phenocopy mutant Kras in a mouse model of pancreatic cancer, and concluded that KRAS acts through PI3K signalling to induce cancer.35 While the authors suggested that therapeutic targeting of PI3K signalling might be a promising approach for the treatment of pancreatic cancer, our data indicate that response to treatment will be dependent on the combination of genetic events in individual tumours.