The incidence of oropharyngeal cancer (OPSCC) has escalated in the past few decades; this has largely been triggered by high-risk human papillomavirus (HPV). Early cancer screening is needed for timely clinical intervention and may reduce mortality and morbidity, but the lack of knowledge about premalignant lesions for OPSCC poses a significant challenge to early detection. Biomarkers that identify individuals at high risk for OPSCC may act as surrogate markers for precancer but these are limited as only a few studies decipher the multistep progression from HPV infection to OPSCC development. Here, we summarize the current literature describing the multistep progression from oral HPV infection, persistence, and tumor development in the oropharynx. We also examine key challenges that hinder the identification of premalignant lesions in the oropharynx and discuss potential biomarkers for oropharyngeal precancer. Finally, we evaluate novel strategies to improve investigations of the biological process that drives oral HPV persistence and OPSCC, highlighting new developments in the establishment of a genetic progression model for HPV + OPSCC and in vivo models that mimic HPV + OPSCC pathogenesis.

The incidence of human papillomavirus-positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) is rising rapidly and has exceeded cervical cancer to become the most common HPV-induced cancer in developed countries. Since patients with HPV + OPSCC respond very favorably to standard aggressive treatment, the emphasis has changed to reducing treatment intensity. However, recent multi-center clinical trials failed to show non-inferiority of de-escalation strategies on a population basis, highlighting the need to select low-risk patients likely to respond to de-intensified treatments. In contrast, there is a substantial proportion of patients who develop recurrent disease despite aggressive therapy. This supports that HPV + OPSCC is not a homogeneous disease, but comprises distinct subtypes with clinical and biological variations. The overall goal for this review is to identify biomarkers for HPV + OPSCC that may be relevant for patient stratification for personalized treatment. We discuss HPV + OPSCC as a heterogeneous disease from multifaceted perspectives including clinical behavior, tumor morphology, and molecular phenotype. Molecular profiling from bulk tumors as well as single-cell sequencing data are discussed as potential driving factors of heterogeneity between tumor subgroups. Finally, we evaluate key challenges that may impede in-depth investigations of HPV + OPSCC heterogeneity and outline potential future directions, including a section on racial and ethnic differences.

WW‐domain‐binding protein 2 ( WBP2 ) is an oncogene that drives breast carcinogenesis through regulating Wnt, estrogen receptor (ER), and Hippo signaling. Recent studies have identified neoteric modes of action of WBP2 other than its widely recognized function as a transcriptional coactivator. Here, we identified a previously unexplored role of WBP2 in inflammatory signaling in breast cancer via an integrated proteogenomic analysis of The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA BRCA) dataset. WBP2 was shown to enhance the migration and invasion in triple‐negative breast cancer (TNBC) cells especially under tumor necrosis factor alpha (TNF‐α) stimulation. Molecularly, WBP2 potentiates TNF‐α‐induced nuclear factor kappa B (NF‐κB) transcriptional activity and nuclear localization through aggrandizing ubiquitin‐mediated proteasomal degradation of its upstream inhibitor, NF‐κB inhibitor alpha (NFKBIA; also known as IκBα). We further demonstrate that WBP2 induces mRNA stability of beta‐transducin repeat‐containing E3 ubiquitin protein ligase ( BTRC ), which targets IκBα for ubiquitination and degradation. Disruption of IκBα rescued the impaired migratory and invasive phenotypes in WBP2 ‐silenced cells, while loss of BTRC ameliorated WBP2‐driven migration and invasion. Clinically, the WBP2‐BTRC‐IκBα signaling axis correlates with poorer prognosis in breast cancer patients. Our findings reveal a pivotal mechanism of WBP2 in modulating BTRC‐IκBα‐NF‐κB pathway to promote TNBC aggressiveness.

Human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV+ OPSCC) is now the leading HPV+ cancer in the United States and United Kingdom. Despite high cure rates, a significant subset of patients have aggressive HPV+ OPSCC that recurs; deciphering the underlying mechanisms will identify biomarkers that delineate patient subgroups for personalized treatment. In a comprehensive investigation using complementary clinically-relevant models of HPV+ OPSCC, we demonstrated that elevated expression of a HPV16 E6 spliced isoform (E6*I) compared to full-length E6 (E6FL), is critical for aggressive invasion. Introduction of splice switching oligonucleotides (SSOs) to inhibit E6FL splicing, effectively mitigated invasion. Mechanistic studies revealed that aggressive invasion occurs via E6*I-induced endocytosis of E-cadherin (ECAD) from the cell membrane, consistent with partial epithelial-to-mesenchymal transition (p-EMT). The clinical relevance of this mechanism was validated in patient cohorts where a reduced ratio of E6FL to all E6 splice variants was associated with high p-EMT signature, lower membrane:cell ECAD, and worse recurrence-free survival. Together, our findings show that low membrane:cell ECAD ratio in pre-treatment biopsies of HPV+ OPSCC, could stratify patients according to risk; patients with a low ratio may not be candidates for treatment de-intensification trials. Importantly, since ECAD detection is by immunohistochemistry, which is widely used even in diagnostic pathology laboratories with limited resources, membrane:cell ECAD ratio could be a clinically scalable biomarker. Targeting E6FL splicing with SSOs should be explored further as a logical strategy for therapeutic intervention in patients with HPV+ OPSCC.

Purpose: Human papillomavirus (HPV) integration (HPVint) is associated with carcinogenesis and tumor progression in HPV-associated cancers, including head and neck squamous cell carcinomas (HNSCC). Although its impact on human DNA has been well characterized, its relationship with clinical outcomes remains unconfirmed. Experimental Design: We analyzed HPVint events from 261 HPV-associated HNSCC bulk and single-cell RNA sequencing (scRNA-seq) samples from five cohorts, including 62 from a new University of Michigan cohort, and DNA HPVint events from 102 HPV(+) HNSCC participants in two of the cohorts. We investigated the consequences of HPVint both with respect to human and HPV gene expression and clinical outcomes (recurrence and overall survival). Results: By leveraging this large meta-cohort of HNSCC, we first reveal an oncogenic gene network based on the recurrent HPVint locations in the human genome and gene expression alterations, highlighting key recurrent and overexpressed genes, including NR4A2, CD274, and CCER1, and genes from the CAMK and KLF families. We then stratify HPVint-positive participants by risk using HPV RNA features, specifically spliced HPV–human fusion transcripts (E1* integration) and HPV gene expression ratios, showing that subsets of participants have worse clinical outcomes based on these two candidate biomarkers. Conclusions: By focusing on RNA instead of DNA, we expand our understanding of the carcinogenic mechanisms of HPVint, in part addressing the conflicting findings of whether HPVint is associated with aggressive phenotypes and worse clinical consequences, and provide potential biomarkers to advance precision oncology in HPV-associated HNSCC. Newly identified genes with recurrent integration events may serve as candidates for targeted therapy.

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