Indisulam Shows an Anti-Cancer Effect on HPV+ and HPV- Head and Neck Cancer.

Background/Objectives: HPV+ head and neck squamous cell carcinoma has been shown to have a unique genomic background, requiring researchers to study it as its own distinct type of cancer. HPV+ tumors have been shown to exhibit fewer genetic mutations in cancer drivers as opposed to their HPV- counterparts. In this paper, we explored how targeting post-transcriptional changes, specifically alternative splicing events, could serve as a potential mechanism to treat HPV+ cancer. Methods: Using indisulam, a drug that targets alternative splicing through the degradation of RBM39, we treated various HPV+ and HPV- cell lines and assessed tumor cell viability. We also tested indisulam in vivo to evaluate its effect on tumor volume. Additionally, we analyzed gene expression differences between indisulam-treated subjects and their non-treated counterparts. Results: Indisulam treatment led to a reduction in tumor cell viability in both HPV+ and HPV- cell lines. In vivo experiments showed a reduction in tumor volume following indisulam treatment. Gene expression analysis revealed that indisulam induces consistent differential gene expression changes and highly enriches interferon pathways in treated HPV+ cell lines. Conclusions: These findings suggest that targeting alternative splicing via indisulam may be a promising therapeutic approach for HPV+ cancers. Further research is required to establish indisulam as a viable anti-cancer treatment in clinical settings.