Targeted Treatment of HPV16-positive and -negative SCC Cells With Small Molecule Tyrosine Kinase Inhibitors and Everolimus Affects MMP2 and MMP14 Expression.

BACKGROUND/AIM: The rise of targeted therapies in the treatment of head and neck squamous cell carcinoma (HNSCC) has considerably widened the treatment range. Matrix metalloproteinases (MMPs) are key regulators of the tumor development of many cancer entities, which makes them a promising target for new treatment options. We examined the expression patterns of MMP2 and MMP14 in human papillomavirus (HPV)-positive and -negative SCC lines after treatment with small molecule tyrosine kinase inhibitors (TKIs) and a mechanistic target of rapamycin (mTOR) inhibitor in vitro. MATERIALS AND METHODS: Cells of two human HPV-negative cell lines (UMSCC-11A/-14C) and one HPV-positive cell line (CERV196) were incubated with 20 µmol/l of erlotinib, gefitinib, nilotinib, dasatinib, or everolimus for 24-96 h. Cell proliferation was assessed by proliferation assay and the protein concentrations of MMP2 and MMP14 by sandwich enzyme-linked immunosorbent assay. For statistical analysis, the results were compared with those of untreated SCC cells. RESULTS: MMP2 and MMP14 were expressed in all three tested cell lines; expression levels were highest in the UMSCC-14C cell line. The tested TKIs significantly (p<0.05) reduced MMP2 expression in the UMSCC-14C cell line. In the HPV-positive cell line, the drugs led to an increase in MMP2 and MMP14 expression. CONCLUSION: Dysregulations in MMP signaling are involved in tumorigenesis and metastasis of HNSCCs; MMP2 has been noted as a potential biomarker. The expression of MMP2 and MMP14 is influenced effectively by small molecule TKIs and everolimus. Based on our data, future research should concentrate on a better understanding of the interplay between tumor microenvironment and tumor cells in vitro and in vivo.

FGF Expression in HPV16-positive and -negative SCC After Treatment With Small-molecule Tyrosine Kinase Inhibitors and Everolimus.

BACKGROUND: Targeted therapies in the treatment of head and neck squamous cell carcinoma (HNSCC) are subject to extensive research. Different mutations of genes belonging to the fibroblast growth factor (FGF) family have been detected in HNSCC. In this study, we examined the expression of FGF1 and FGF2 after treatment with small-molecule tyrosine kinase inhibitors (TKIs) and an inhibitor of mechanistic target of rapamycin (mTOR) in vitro using human papillomavirus (HPV)-positive and -negative SCC lines. MATERIALS AND METHODS: Cells of two human HPV-negative cell lines (UMSCC-11A/-14C) and one HPV-positive cell line (CERV196) were incubated with 20 µmol/l of erlotinib, gefitinib, nilotinib, dasatinib, or everolimus for 24-96 h. Cell proliferation was assessed by proliferation assay and the protein concentrations of FGF1 and FGF2 by sandwich enzyme-linked immunosorbent assay. For statistical analysis, the results were compared with those for untreated HPV-negative SCC cells. RESULTS: FGF1 and FGF2 were detected in all three tested cell lines. The tested TKIs significantly (p<0.05 reduced) FGF1 expression in the UMSCC-11A cell line within the first 24 h. At later time points, the tested TKIs and everolimus significantly (p<0.05) increased FGF1 and FGF2 expression in HPV-negative and -positive cancer cell lines. The effect was stronger in the HPV-positive cell line. CONCLUSION: Alterations in FGF signalling are considered to be relevant drivers of tumourigenesis in some HNSCCs. Our results show that the expression of FGF1 and -2 can be influenced effectively by small-molecule TKIs and everolimus. Based on our data, future research should include combinations of specific FGF inhibitors, mTOR inhibitors and other TKIs in the treatment of HNSCC and research on FGF-mediated drug escape mechanisms.