Method: Conditioned media was taken from HPV-positive and HPV-negative oropharyngeal carcinoma lines, and incubated with normal oral fibroblasts. Further conditioned media was then collected from the stimulated fibroblasts and analysed through a combination of contemporary “silicone stopper” based migration assays, and MTS proliferation assays. Cell line conditioned media and stimulated fibroblast conditioned media were then assessed for candidate cytokine markers to determine the cause of observed changes in cellular migration using a combination of Cytokine Arrays, Flow Cytometry and ELISA techniques
Result: HPV-negative cell lines demonstrated a marked increase in void closure in response to conditioned media when compared to control (P<0.01). HPV-positive cell lines demonstrated no significant change in void closure when compared to control. No significant difference in proliferation was observed between HPV-positive and HPV-negative cell lines (P>0.05). Our data supports a marked difference in tumour-stromal interaction between HPV-positive and -negative oropharyngeal carcinoma. Furthermore, interrogation of cytokine profiles of both tumour and fibroblast conditioned media provides evidence of a supportive microenvironmental pathway characteristic to HPV-negative disease
Conclusion: HPV-negative oropharyngeal carcinoma lines are capable of inducing a fibroblast secretory profile that is supportive of tumour migration. This is not a feature of HPV-positive lines, and may contribute to the poorer clinical prognosis of HPV-negative disease. We describe a cytokine pathway that supports the observed migratory response in vitro, and which may be subject to clinical blockade