RESUMEN
Mechanisms of tumorigenesis in sinonasal squamous cell carcinoma (SNSCC) remain poorly described due to its rare nature. A subset of SNSCC are associated with the human papillomavirus (HPV); however, it is unknown whether HPV is a driver of HPV-associated SNSCC tumorigenesis or merely a neutral bystander. We hypothesized that performing the first large high-throughput sequencing study of SNSCC would reveal molecular mechanisms of tumorigenesis driving HPV-associated and HPV-independent SNSCC and identify targetable pathways. High-throughput sequencing was performed on 64 patients with HPV-associated and HPV-independent sinonasal carcinomas. Mutation annotation, viral integration, copy number, and pathway-based analyses were performed. Analysis of HPV-associated SNSCC revealed similar mutational patterns observed in HPV-associated cervical and head and neck squamous cell carcinoma, including lack of TP53 mutations and the presence of known hotspot mutations in PI3K and FGFR3. Further similarities included enrichment of APOBEC mutational signature, viral integration at known hotspot locations, and frequent mutations in epigenetic regulators. HPV-associated SNSCC-specific recurrent mutations were also identified including KMT2C , UBXN11 , AP3S1 , MT-ND4 , and MT-ND5 . Mutations in KMT2D and FGFR3 were associated with decreased overall survival. We developed the first known HPV-associated SNSCC cell line and combinatorial small molecule inhibition of YAP/TAZ and PI3K pathways synergistically inhibited tumor cell clonogenicity. In conclusion, HPV-associated SNSCC and HPV-independent SNSCC are driven by molecularly distinct mechanisms of tumorigenesis. Combinatorial blockade of YAP/TAZ and vertical inhibition of the PI3K pathway may be useful in targeting HPV-associated SNSCC whereas targeting MYC and horizontal inhibition of RAS/PI3K pathways for HPV-independent SNSCC. One Sentence Summary: This study solidifies HPV as a driver of HPV-associated SNSCC tumorigenesis, identifies molecular mechanisms distinguishing HPV-associated and HPV-independent SNSCC, and elucidates YAP/TAZ and PI3K blockade as key targets for HPV-associated SNSCC.
RESUMEN
Background: HPV-associated oropharyngeal cancer (HPV+OPSCC) is the most common HPV-associated cancer in the United States yet unlike cervical cancer lacks a screening test. HPV+OPSCCs are presumed to start developing 10-15 years prior to clinical diagnosis. Circulating tumor HPV DNA (ctHPVDNA) is a sensitive and specific biomarker for HPV+OPSCC. Taken together, blood-based screening for HPV+OPSCC may be feasible years prior to diagnosis. Methods: We developed an HPV whole genome sequencing assay, HPV-DeepSeek, with 99% sensitivity and specificity at clinical diagnosis. 28 plasma samples from HPV+OPSCC patients collected 1.3-10.8 years prior to diagnosis along with 1:1 age and gender-matched controls were run on HPV-DeepSeek and an HPV serology assay. Results: 22/28 (79%) of cases and 0/28 controls screened positive for HPV+OPSCC with 100% detection within four years of diagnosis and a maximum lead time of 7.8 years. We next applied a machine learning model classifying 27/28 cases (96%) with 100% detection within 10 years. Plasma-based PIK3CA gene mutations, viral genome integration events and HPV serology were used to orthogonally validate cancer detection with 68% (19/28) of the cohort having multiple cancer signals detected. Molecular fingerprinting of HPV genomes was performed across patients demonstrating that each viral genome was unique, ruling out contamination. In patients with tumor blocks from diagnosis (15/28), molecular fingerprinting was performed within patients confirming the same viral genome across time. Conclusions: We demonstrate accurate blood-based detection of HPV-associated cancers with lead times up to 10 years before clinical cancer diagnosis and in doing so, highlight the enormous potential of ctDNA-based cancer screening.