PTEN and primary effusion lymphoma: Unlike induction of apoptosis in primary effusion lymphomas with constitutively activated PI3K/Akt/mTOR signaling [32], gliomas [33] or HER2-amplified and PIK3CA-mutant breast cancer cells [16], BEZ235 monotherapy mainly induced cell-cycle arrest at G1 phase in NSCLC cells, even in CL141 cells that had lost PTEN expression.