We knocked down PHLDA2 in ErbB2-positive NSCLC cells and demonstrated that PHLDA2 knockdown increased NSCLC cell growth and reduced sensitivity of the NSCLC cells to the ErbB2 tyrosine kinase inhibitor, lapatinib, consistent with its putative function as an AKT pathway inhibitor and suggestive of a candidate tumor suppressor function. The gene discussed is PHLDA2; the disease is non-small cell lung carcinoma.