Probes for P16

High-risk human papillomavirus (HR-HPV) can cause oropharyngeal squamous cell carcinoma (OpSCC). The revised 8th edition of the AJCC Staging Manual now stages OpSCC by incorporating p16 immunohistochemistry (IHC), the surrogate marker for HPV status. This study assessed the prognostic values of p16 and HPV markers.We identified 244 OpSCC patients diagnosed between 2000-2008 from the British Columbia Cancer Registry with enough tissue to conduct experiments. Formalin-fixed, paraffin-embedded tissue sections were stained for p16 IHC, RNA in situ hybridization (ISH) HPV 16 and 18, and DNA ISH HR-HPV. Electronic charts were reviewed to collect clinical and outcome data. Combined positive RNA and/or DNA ISH was used to denote HPV status.HPV was positive among 77.9% of samples. Using HPV as the benchmark, p16 IHC had high sensitivity (90.5%), but low specificity (68.5%). Distinct subgroups of patients were identified by sequential separation of p16 then HPV status. Among both p16-positive and p16-negative groups, HPV-positive patients were younger, more males, and had better clinical outcomes, especially 5-year overall survival. We further evaluated the technical costs associated with HPV testing.HPV is more prognostic than p16 for OpSCC. Clinical laboratories can adopt HPV RNA ISH for routine analysis.This article is protected by

Human papillomavirus (HPV) is responsible for a growing proportion of oropharyngeal squamous cell carcinomas (OPSCCs) among men and White individuals. Whether similar trends apply to women, non-Whites, and non-oropharyngeal squamous cell carcinomas (non-OPSCCs) is unknown.This is a cross-sectional analysis combining 2 multi-institutional case series of incident head and neck squamous cell carcinoma (HNSCC) cases. Incident HNSCCs from 1995 to 2012 were enrolled retrospectively using banked tumor samples and medical record abstraction. Incident HNSCCs from 2013 to 2019 were enrolled prospectively. The prevalence of tumor HPV biomarkers was tested over 3 time periods (1995-2003, 2004-2012, and 2013-2019). Centralized testing was done for p16 immunohistochemistry (p16) and oncogenic HPV in situ hybridization (ISH).A total of 1209 incident cases of HNSCC were included. Prevalence of p16- and ISH-positive tumors increased significantly for oropharynx cancers over time. The majority were positive after 2013 for White patients (p16, 92%; P < .001; ISH 94%; P < .001), Black patients (p16, 72%; P = .021; ISH 67%; P = .011), and Hispanic patients (p16, 100%; P = .04; ISH 100%; P = .013). For women with OPSCC, the prevalence of p16- and ISH-positive tumors increased significantly to 82% (P < .001) and 78% (P = .004), respectively. For non-OPSCCs, there was increased p16 and ISH positivity overall with 24% p16 and 16% ISH positivity in the most recent time period (P < .001 for both).The majority of OPSCCs in US tertiary care centers are now p16 and ISH positive for all sex and race groups. In some populations in the United States, 91% of OPSCCs are now caused by HPV. Few non-OPSCCs are p16 and ISH positive.

While P16 immunohistochemistry (IHC) is a well-established surrogate marker of Human Papillomavirus (HPV) in oropharyngeal squamous cell carcinoma (OSCC), Retinoblastoma 1 (RB1) loss may lead to p16 overexpression in the absence of HPV. We determined the proportion of p16-positive/HPV-negative OSCC with RB1 loss and other alterations in RB1/p16 pathway, and tested RB1 IHC as a prognostic biomarker for OSCC, along with the 8th edition of AJCC staging manual. P16 and RB1 IHC and HPV DNA in situ hybridization (ISH) were performed on 257 OSCC. High risk HPV RNA ISH, RB1 fluorescence in situ hybridization (FISH), and next generation sequencing (NGS) were done on p16-positive/HPV DNA ISH-negative OSCC. Disease free survival (DFS) was used as an endpoint. In the entire cohort and in p16-positive (n = 184) and p16-negative (n = 73) subgroups, AJCC 8th edition staging correlated with DFS (p < 0.01). RB1 IHC showed RB1 loss in p16-positive OSCC only (79/184, 43%). RB1 loss by IHC is associated with a better DFS, without providing additional prognostic information for patients with p16-positive OSCC. HPV RNA ISH was positive in 12 of 14 HPV DNA ISH-negative cases. RB1 IHC showed loss in 10 of 15 HPV DNA ISH-negative cases and in 1 of 2 HPV RNA ISH-negative cases. Overall, only one case of p16-positive/HPV RNA ISH-negative OSCC showed RB1 loss by IHC (1/184, 0.5%). Of the 10 p16-positive and HPV DNA ISH-negative cases with RB1 loss by IHC, 2 had RB1 hemizygous deletion and 3 showed Chromosome 13 monosomy by FISH. No RB1 mutations were detected by NGS. Other molecular alterations in p16-positive/HPV DNA ISH-negative cases included TP53 and TERT mutations and DDX3X loss. HPV-independent RB1 inactivation rarely results in false positive p16 IHC. RB1 inactivation by high risk HPV E7 oncoprotein may co-exist with RB1 deletion. RB1 loss is a favorable prognosticator and occurs exclusively in p16-positive OSCC. The 8th edition of the AJCC staging manual satisfactorily predicts DFS of OSCC patients.

HDAC inhibitors show therapeutic promise for skin malignancies; however, the roles of specific HDACs in adult epidermal homeostasis and disease are poorly understood. We find that homozygous epidermal co-deletion of Hdac1 and Hdac2 in adult mouse epidermis causes reduced basal cell proliferation, apoptosis, inappropriate differentiation, and eventual loss of Hdac1/2-null keratinocytes. Hdac1/2 deficient epidermis displays elevated acetylated p53 and increased expression of the senescence gene p16. Loss of p53 partially restores basal proliferation, whereas p16 deletion promotes long-term survival of Hdac1/2-null keratinocytes. In activated GLI2-driven pre-basal cell carcinoma, Hdac1/2 deletion dramatically reduces proliferation and increases apoptosis, and knockout of either p53 or p16 partially rescues both proliferation and basal cell viability. Topical application of the HDAC inhibitor Romidepsin to normal epidermis or GLI2ΔN-driven lesions produces similar defects to genetic Hdac1/2 deletion, and these are partially rescued by loss of p16. These data reveal essential roles for HDAC1/2 in maintaining proliferation and survival of adult epidermal and basal cell carcinoma progenitors and suggest efficacy of therapeutic HDAC1/2 inhibition will depend in part on the mutational status of p53 and p16.

Ocular adnexal (OA) sebaceous carcinoma is an aggressive malignancy. Oncologic drivers of ocular sebaceous carcinoma are incompletely understood. A retrospective search of our pathology archives for OA sebaceous carcinoma identified 18 primary resection specimens. Immunohistochemistry for p16 and ZEB1 and RNA in situ hybridization for high-risk human papillomavirus (HPV) subtypes were performed. High-risk HPV was demonstrated in 2/11 (18%) cases. p16 overexpression was observed in 10/11 (91%). No association between gender, age at presentation, tumor location, intraepithelial spread, tumor size, and T stage was observed between HPV-driven and nonviral cases. High expression of ZEB1 was observed in the intraepithelial component of 4/14 (28%) cases and in the subepithelial component of 1/13 (7%) cases. ZEB1 overexpression was not associated with HPV-status, T stage, or tumor size. As previously described by others, our findings suggest that a subset of OA sebaceous carcinomas may arise via an HPV-dependent pathway. However, unlike high-risk HPV-driven carcinomas of the oropharynx, we did not identify an association between HPV-status and prognostic features. Furthermore, p16 expression was not a useful surrogate marker for HPV-driven disease. ZEB1 overexpression is not associated with HPV in our cohort of ocular sebaceous carcinoma.

The transcriptional activity of high-risk human papillomaviruses (HR-HPV) within oropharyngeal squamous cell carcinomas (OPSCC) has been linked to improved survival of patients. HR-HPV mRNA silver in situ hybridization (SISH) was evaluated on a cohort of OPSCC and compared with viral HPV DNA tests and p16 expression. Clinical outcomes of HPV-driven OPSCC and non-HPV related OPSCC were also studied.We evaluated 67 OPSCC and 3 papillomas, obtained from 62 patients, for detection of HR-HPV DNA by PCR tests. The positive samples were additionally studied by the SISH method using three probes of HPV16, HPV18, and HP33, and for p16 expression detected by immunohistochemistry. SISH assays were evaluated for the presence/number and intensity of signals in cancer cells. Prognostic significance of HPV status in our cohort was evaluated with univariate and multivariate statistics.According to the HR-HPV PCR tests, 46 (69%) OPSCC cases were HPV positive, while three papillomas were negative. Of total 46 HPV-positive OPSCCs, 43 cases were also SISH-positive, while p16 overexpression was found in 45 of 46 HPV positive OPSCC cases. In OPSCC specimens, the sensitivity and specificity of the combined SISH probes (HPV16 and 33) were both 100.00%, when compared to HPV PCR. HPV positivity of the tumors appeared significant for predicting progression-free survival, cause specific survival and overall survival in a multivariate setting.The recently developed mRNA SISH methodology can detect HPV-driven OPSCCs without any additional test in 79% of cases. Positive SISH signals enable the visualization of viral transcripts required to recognize clinically relevant HPV infection. However, rare and tiny signals require an experienced pathologist to establish a consensus interpretation of results. The currently applied HR-HPV mRNA SISH analysis may serve as a groundwork for additional studies.

Human papillomavirus-related oropharyngeal squamous cell carcinoma (HPV-OPSCC) presents frequently as metastasis in a neck lymph node that may be cystic or necrotic. Fine-needle aspiration (FNA) biopsies are often first-line diagnostic procedures. p16 immunohistochemistry (IHC) is a surrogate marker for high-risk HPV (hrHPV) infection but can be challenging to interpret. This study evaluated the use of hrHPV in situ hybridization (ISH) in cytology cell blocks of cystic neck lesions.Twenty-four FNA cases with cell blocks and surgical correlates were evaluated. p16 IHC and hrHPV ISH were assessed on cell blocks (C-p16 and C-hrHPV ISH), and hrHPV ISH on surgical samples (S-hrHPV ISH). All results were classified as negative, positive, or equivocal.Two cases were excluded because of insufficient tissue on recut. On the basis of C-hrHPV ISH cases, 12 were positive, 5 were negative, and 5 were equivocal. All 12 positive C-hrHPV ISH cases had concordant S-hrHPV ISH with no false positives. Of the 5 negative C-hrHPV ISH cases, 4 had concordant S-hrHPV ISH, and 1 had a discordant S-hrHPV ISH. Of the 5 equivocal C-hrHPV ISH cases, S-hrHPV ISH were both positive and negative. Fourteen cases were equivocal by C-p16; 9 cases were reliably classified by C-hrHPV ISH (5 positive, 4 negative; 64%).C-hrHPV ISH can be reliably used, especially when positive. A negative or equivocal interpretation of C-hrHPV ISH may warrant repeat testing. Compared to C-p16, C-hrHPV ISH is more frequently diagnostic and could be helpful for HPV-OSCC diagnosis and management.

There is limited literature detailing the histology of pharyngeal papillomas. Herein, we report our experience with papillomas occurring in the oro-and nasopharynx that have both squamous and respiratory features akin to the sinonasal Schneiderian papilloma. We retrospectively reviewed pharyngeal papillomas that were composed of both squamous and respiratory epithelium received at our institution between 2010 and 2020. Cases of sinonasal papillomas directly extending into the pharynx were excluded. Immunohistochemistry for p16 as well as RNA in situ hybridization to evaluate for 6 low-risk and 18 high-risk HPV genotypes were performed on all cases. Thirteen cases were included. Mean age was 61 with 12 males and 1 female. While often incidentally found, presenting symptoms included globus sensation, hemoptysis, and hoarseness of voice. Histologically, all tumors consisted of squamous and respiratory epithelium with neutrophilic infiltrates arranged in an exophytic/papillary architecture that was reminiscent of the exophytic type of Schneiderian papilloma. Immunohistochemistry for p16 was negative in all papillomas. 85% were positive for low-risk human papillomavirus (HPV) subtypes and all were negative for high-risk HPV subtypes. A well-differentiated, invasive squamous cell carcinoma was associated with two of the cases. Papillomas with squamous and respiratory features similar to the sinonasal exophytic Schneiderian papilloma can arise in the oro- and nasopharynx and like their sinonasal counterparts show an association with HPV. While many in this series were benign, they can be harbingers for invasive squamous cell carcinoma.

Esophageal verrucous carcinoma (VSCC) is a rare and morphologically distinct type of esophageal squamous cell carcinoma (SCC). Diagnosing VSCC on biopsy material is challenging given the lack of significant atypia and the presence of keratinizing epithelium and exophytic growth. The molecular pathogenesis of VSCC remains unclear. The aim of this study was to characterize the genomic landscape of VSCC in comparison to conventional esophageal SCC. Three cases of VSCC from the Brigham and Women's Hospital pathology archive were identified. Formalin-fixed, paraffin-embedded (FFPE) tumor tissue was used for p16 immunohistochemistry (IHC), high-risk HPV in situ mRNA hybridization (ISH), and DNA isolation. Tumor DNA was sequenced using a targeted massively parallel sequencing assay enriched for cancer-associated genes. Three additional cases of VSCC were identified by image review of The Cancer Genome Atlas (TCGA) esophageal SCC cohort. VSCC cases were negative for p16 IHC and high-risk HPV ISH. TP53 mutations (p<0.001) and copy number variants (CNVs) for CDKN2A (p<0.001), CDKN2B (p<0.01) and CCND1 (p<0.01) were absent in VSCC and significantly less frequent in comparison to conventional SCC. Five VSCC cases featured SMARCA4 missense mutations or inframe deletions compared to only 4/88 conventional SCC cases (p<0.001). VSCC featured driver mutations in PIK3CA, HRAS, and GNAS. Recurrent CNVs were rare in VSCC. VSCC is not only morphologically but also genetically distinct from conventional esophageal SCC, featuring frequent SMARCA4 mutations and infrequent TP53 mutations or CDKN2A/B CNVs. Molecular findings may aid in establishing the challenging diagnosis of VSCC. This article is protected by

Vulvar squamous cell carcinoma (VSCC) pathogenesis is traditionally defined by the presence or absence of human papillomavirus (HPV), but the definition of these groups and their molecular characteristics remains ambiguous across studies. Here, we present a retrospective cohort analysis of 36 patients with invasive VSCC where HPV status was determined using RNA in situ hybridization (ISH) and polymerase chain reaction (PCR). Clinical annotation, p16 immunohistochemistry (IHC), programmed death ligand-1 (PD-L1) IHC, HPV16 circular E7 RNA (circE7) detection, and RNA-sequencing (RNA-seq) of the cases was performed. A combination of ISH and PCR identified 20 cases (55.6%) as HPV-positive. HPV-status did not impact overall survival (HR: 1.36, 95% CI: 0.307 to 6.037, p=0.6857) or progression-free survival (HR: 1.12, 95% CI: 0.388 to 3.22, p=0.8367), and no significant clinical differences were found between the groups. PD-L1 expression did not correlate with HPV status, but increased expression of PD-L1 correlated with worse overall survival. Transcriptomic analyses (n=23) revealed distinct groups, defined by HPV status, with multiple differentially expressed genes previously implicated in HPV-induced cancers. HPV-positive tumors showed higher global expression of endogenous circular RNAs (circRNAs), including several circRNAs that have previously been implicated in the pathogenesis of other cancers.

Significant variation in human papillomavirus (HPV) prevalence in oropharyngeal squamous cell carcinoma (OPSCC) across countries ranging from 11% in Brazil to 74% in New Zealand has been reported earlier. The aim of this study was to systematically review the most recently published studies on the occurrence of HPV in OPSCC globally. PubMed and Embase were systematically searched for articles assessing the occurrence of HPV+ OPSCC published between January 2016 and May 2021. Studies with a study period including 2015 and the following years were included. Both HPV DNA and/or p16 were accepted as indicators of HPV+ OPSCC. 31 studies were enrolled comprising 49,564 patients with OPSCC (range 12-42,024 patients per study) from 26 different countries covering all continents. The lowest occurrences of HPV+ OPSCC were observed in India (0%) and Spain (10%) and the highest occurrences were observed in Lebanon (85%) and Sweden (70%). We observed great variation in HPV prevalence in OPSCC worldwide varying from 0% to 85%. The highest occurrences of HPV+ OPSCC were found in general in Northern European countries, USA, Lebanon, China, and South Korea. We observed a trend of increase in HPV-positivity, indicating a mounting burden of HPV+ OPSCC.