Fig. 6

Genetic annotation of the HPV^neg HNSCC PDX models and evaluation of selected palbociclib-based treatment combinations in PDX models. a Whole exome sequencing was conducted in five selected PDX models. CDKN2A, CCND1, PIK3CA, and RB1 status of the 5 selected PDX models are shown. b Heat map comparing copy number aberrations between matched tumor biopsy and PDX models in a log2 scale. Red colors indicate gains, and blue colors indicate losses. Chr. chromosome. c Scatter plots displaying correlations between PDX DNA VAF and patient tumor DNA VAF. The Spearman correlation value is in the lower right-hand corner of each plot. d–h Five patient-derived xenograft models from HPV^neg HNSCC patients were treated with vehicle (sodium lactate buffer, 50 mmol/L, pH 4.0), palbociclib (60 mg/kg once daily), alpelisib (20 mg/kg once daily), cetuximab (1 mg/kg twice a week), palbociclib plus alpelisib, palbociclib plus cetuximab, and palbociclib plus cisplatin (cisplatin 3 mg/kg once a week) (n = 5–10). Tumor growth was measured every other day. Tumor volumes are shown. The data are shown as the mean ± SEM. n.s., not significant; *, P < 0.05; **, P < 0.01; ***, P < 0.001; ***, P < 0.0001, as estimated by two-way ANOVA. i Summary of TGI values of each treatment in five PDX models. MUT: mutation, AMP: amplification, DEL: deletion, TGI (%): tumor growth inhibition (%)