To determine whether a CDKN2A mutation or homologous deletion (found in 38% of our NSCLC PDX panel) can be used as a biomarker of response to a CDK4/6 inhibitor in NSCLC, treatment with palbociclib alone or in combination with chemotherapies was carried out in two ADCs with CDKN2A homologous deletions and two SCCs with CDKN2A mutations (Figure 5a). Here, CDKN2A is linked to non-small cell lung carcinoma.