Interestingly, whilst in preclinical models mutations in KRAS have been found to confer resistance to PI3K pathway inhibition, as discussed above, in this trial 2/7 ovarian cancer patients with coexisting PIK3CA and KRAS or BRAF mutations responded to the anti-PI3K pathway treatment (Janku et al., 2012). Here, PIK3CB is linked to ovarian carcinoma.