Comparative molecular profiling of HPV-induced squamous cell carcinomas

Prognostic implications of HIF-1α expression in anal squamous cell carcinoma treated with intensity-modulated radiotherapy (IMRT)

Background

Hypoxia-inducible factor-1α (HIF-1α) is a crucial transcription factor activated under hypoxic conditions, known to regulate genes associated with tumor survival, progression, and response to therapy. This study aimed to evaluate the prognostic significance of HIF-1α expression in patients with anal squamous cell carcinoma (ASCC) undergoing chemoradiation therapy.

Methods

We conducted a retrospective analysis of 28 ASCC patients treated with intensity-modulated radiotherapy (IMRT) at our center from 2009 to 2022. HIF-1α expression was assessed via immunohistochemistry on formalin-fixed paraffin-embedded tissue specimens. Quantitative analysis of HIF-1α expression was performed, and its relationship with clinical outcomes, including disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and overall survival (OS), was examined using Cox regression models. Furthermore, ASCC tissue specimens from 17 patients were analyzed for potential PIK3CA mutations using Sanger sequencing.

Results

High HIF-1α expression was significantly associated with poorer DFS (p = 0.005), LRRFS (p = 0.012), and OS (p = 0.009). HIF1α expression was marginally significantly higher in males compared to females (p = 0.056) while there was no significant difference found based on tumor stage or p16 status. However, a positive correlation was identified between BMI and HIF-1α levels (Pearson correlation r = 0.5, p = 0.0084), suggesting a link between metabolic status and tumor hypoxia. Only one patient exhibited a PIK3CA mutation, preventing a reliable assessment of its correlation with HIF-1α expression.

Conclusion

Our findings underscore the importance of HIF-1α as a potential biomarker for predicting survival outcomes in ASCC patients treated with chemoradiation. The association between higher BMI and increased HIF-1α expression may provide insights into the interplay between metabolic health and tumor biology in ASCC. Further studies with larger cohorts are needed to validate these findings and explore targeted therapies focusing on HIF-1α modulation.

Prevalence and prognostic value of PD-L1 expression and tumor mutational burden in persistent, recurrent, or metastatic cervical cancer

OBJECTIVE

To evaluate the prevalence and prognostic role of programmed death ligand 1 (PD-L1) expression and tumor mutational burden (TMB) in patients with non-immunotherapy-treated advanced cervical cancer.

METHODS

Clinical data were retrospectively collected from medical records between January 1, 2008, and December 31, 2016, at Asan Medical Center (Korea); archived tumor samples were assessed for PD-L1 expression (combined positive score [CPS] ≥1) and TMB (≥175 mutations/exome). Overall survival (OS) was defined as time from advanced diagnosis or initiation of first-line or second-line systemic therapy until death/last follow-up. The association of OS with PD-L1 expression and TMB were analyzed using the log-rank test and Cox proportional hazards model adjusted for covariates.

RESULTS

Of 267 patients, 76.0% had squamous cell carcinoma (SCC), 24.0% had adenocarcinoma (AC)/adenosquamous carcinoma (ASC), 64.4% had PD-L1 CPS ≥1, and 32.6% had TMB ≥175 mutations/exome. PD-L1 CPS ≥1 and TMB ≥175 mutations/exome were more prevalent in SCC than in AC/ASC (73.9% and 37.2% vs. 34.4% and 17.7%). There was no association between OS and PD-L1 expression (CPS ≥1 vs. <1: adjusted hazard ratio [HR]=1.14; 95% confidence interval [CI]=0.84-1.53 from advanced diagnosis); OS trended shorter for the subgroup with TMB ≥175 versus <175 mutations/exome (adjusted HR=1.29; 95% CI=0.95-1.75).

CONCLUSION

Retrospective analysis of non-immunotherapy-treated patients with advanced cervical cancer demonstrated a higher prevalence of PD-L1 CPS ≥1 and TMB ≥175 mutations/exome in SCC versus AC/ASC. PD-L1 CPS ≥1 was not associated with OS; TMB ≥175 mutations/exome showed a trend toward shorter OS. Additional studies are needed to confirm these findings.

PD-L1 expression in vulvar cancer: a systematic review and meta-analysis

Programmed cell death ligand-1 (PD-L1) expression in cancer may predict clinical response to immunotherapeutic treatment with PD-1/PD-L1 inhibitors. Within the vulvar cancer field, PD-L1 expression has only been assessed by a few studies. We conducted a meta-analysis to examine the prevalence of PD-L1 positivity in vulvar cancer. PubMed, Embase, and Cochrane were searched for articles reporting on PD-L1 expression in vulvar cancer. Study selection and data extraction were performed independently by two authors. We extracted data on PD-L1 prevalence in vulvar cancer according to combined positive score (CPS) and tumour proportion score (TPS). Cutoff values for positivity were ≥1 or ≥10 for CPS and ≥1% and ≥5% for TPS. Random-effects models were used to estimate pooled PD-L1 prevalence, with 95% confidence intervals (CIs). Tests of between-study heterogeneity were evaluated by the I2 statistics. Sources of heterogeneity were explored by subgroup analyses and meta-regression. In total, 19 studies were included. Pooled PD-L1 prevalence in vulvar cancer was 83.4% (95% CI: 70.8-91.3; I2  = 80.0) and 53.9% (95% CI: 37.4-69.6; I2  = 93.0) according to CPS and TPS, respectively. Based on TPS, human papillomavirus (HPV)-associated vulvar squamous cell carcinomas (SCC) showed a lower PD-L1 prevalence (39.9%; 95% CI: 13.3-74.2) compared with HPV-independent SCC (62.6%; 95% CI: 33.7-84.6), but meta-regression showed no significant variation in PD-L1 prevalence by HPV status. PD-L1 prevalence was similar in advanced (44.9%; 95% CI: 29.8-61.1) and localized vulvar cancer (56.7%; 95% CI: 18.9-76.7). In conclusion, PD-L1 expression in vulvar cancer is frequent but between-study heterogeneity was high. Based on a subgroup of heterogenous studies, we found no strong variation in PD-L1 prevalence according to HPV status and stage.

Genetic Mutations Associated with Inflammatory Response Caused by HPV Integration in Oropharyngeal Squamous Cell Carcinoma

(1) Background: Head and neck cancer (HNC) ranks as the sixth most prevalent cancer in the world. In addition to the traditional risk factors such as alcohol and tobacco consumption, the implication of the human papillomavirus (HPV) is becoming increasingly significant, particularly in oropharyngeal cancer (OPC). (2) Methods: This study is based on a review analysis of different articles and repositories investigating the mutation profile of HPV-related OPC and its impact on patient outcomes. (3) Results: By compiling data from 38 datasets involving 8311 patients from 12 countries, we identified 330 genes that were further analyzed. These genes were enriched for regulation of the inflammatory response (RB1, JAK2, FANCA, CYLD, SYK, ABCC1, SYK, BCL6, CEBPA, SRC, BAP1, FOXP1, FGR, BCR, LRRK2, RICTOR, IGF1, and ATM), among other biological processes. Hierarchical cluster analysis showed the most relevant biological processes were linked with the regulation of mast cell cytokine production, neutrophil activation and degranulation, and leukocyte activation (FDR < 0.001; p-value < 0.05), suggesting that neutrophils may be involved in the development and progression of HPV-related OPC. (4) Conclusions: The neutrophil infiltration and HPV status emerge as a potential prognostic factor for OPC. HPV-infected HNC cells could potentially lead to a decrease in neutrophil infiltration. By gaining a better molecular understanding of HPV-mediated neutrophil immunosuppression activity, it is possible to identify a meaningful target to boost antitumor immune response in HNC and hence to improve the survival of patients with HNC.

RNA-seq analysis identifies transcriptomic profiles associated with anal cancer recurrence among people living with HIV

BACKGROUND

Chemoradiation therapy (CRT) is the standard of care for squamous cell carcinoma of the anus (SCCA), the most common type of anal cancer. However, approximately one fourth of patients still relapse after CRT.

METHODS

We used RNA-sequencing technology to characterize coding and non-coding transcripts in tumor tissues from CRT-treated SCCA patients and compare them between 9 non-recurrent and 3 recurrent cases. RNA was extracted from FFPE tissues. Library preparations for RNA-sequencing were created using SMARTer Stranded Total RNA-Seq Kit. All libraries were pooled and sequenced on a NovaSeq 6000. Function and pathway enrichment analysis was performed with Metascape and enrichment of gene ontology (GO) was performed with Gene Set Enrichment Analysis (GSEA).

RESULTS

There were 449 differentially expressed genes (DEGs) observed (390 mRNA, 12 miRNA, 17 lincRNA and 18 snRNA) between the two groups. We identified a core of upregulated genes (IL4, CD40LG, ICAM2, HLA-I (HLA-A, HLA-C) and HLA-II (HLA-DQA1, HLA-DRB5) in the non-recurrent SCCA tissue enriching to the gene ontology term 'allograft rejection', which suggests a CD4+ T cell driven immune response. Conversely, in the recurrent tissues, keratin (KRT1, 10, 12, 20) and hedgehog signaling pathway (PTCH2) genes involved in 'Epidermis Development,', were significantly upregulated. We identified miR-4316, that inhibit tumor proliferation and migration by repressing vascular endothelial growth factors, as being upregulated in non-recurrent SCCA. On the contrary, lncRNA-SOX21-AS1, implicated in the progression of many other cancers, was also found to be more common in our recurrent compared to non-recurrent SCCA.

Our study identified key host factors which may drive the recurrence of SCCA and warrants further studies to understand the mechanism and evaluate their potential use in personalized treatment.Key MessageOur study used RNA sequencing (RNA-seq) to identify pivotal factors in coding and non-coding transcripts which differentiate between patients at risk for recurrent anal cancer after treatment. There were 449 differentially expressed genes (390 mRNA, 12 miRNA, 17 lincRNA and 18 snRNA) between 9 non-recurrent and 3 recurrent squamous cell carcinoma of anus (SCCA) tissues. The enrichment of genes related to allograft rejection was observed in the non-recurrent SCCA tissues, while the enrichment of genes related to epidermis development was positively linked with recurrent SCCA tissues.

Comparison of clinicopathological and genomic profiles in anal squamous cell carcinoma between Japanese and Caucasian cohorts

Anal squamous cell carcinoma (ASCC) is a rare tumor of the gastrointestinal tract. We aimed to compare the genetic backgrounds and their effect on clinical outcomes between Japanese and Caucasian patients with ASCC. Forty-one patients diagnosed with ASCC at the National Cancer Center Hospital were enrolled and evaluated for clinicopathological features, human papillomavirus (HPV) infection, HPV genotypes, p16 expression, PD-L1, and association of p16 status with the efficacy of concurrent chemoradiotherapy (CCRT). Target sequencing for hotspot mutations in 50 cancer-related genes was performed using genomic DNA from 30 available samples. Of 41 patients, 34 were HPV-positive (among them, HPV 16 was predominant; 73.2%); 38 patients were p16-positive (92.7%); and 39 patients received CCRT, of whom 36 were p16-positive and three p16-negative. p16-positive patients showed better complete response than p16-negative patients. Among 28 samples, 15 showed mutations in PIK3CA, FBXW7, ABL1, TP53, and PTEN; no difference in mutation profiles between the Japanese and Caucasian cohorts was observed. Actionable mutations were detected in both Japanese and Caucasian patients with ASCC. Genetic backgrounds, such as the HPV 16 genotype and PIK3CA mutations, were common regardless of ethnicity. p16 status may be a prognostic biomarker for CCRT in Japanese patients with ASCC.

PD-L1 expression and CD8 positive lymphocytes in human neoplasms: A tissue microarray study on 11,838 tumor samples

BACKGROUND

Programmed death ligand 1 (PD-L1) is the target of immune checkpoint inhibitor therapies in a growing number of tumor types, but a unanimous picture on PD-L1 expression across cancer types is lacking.

MATERIALS AND METHODS

We analyzed immunohistochemical PD-L1 expression in 11,838 samples from 118 human tumor types and its relationship with tumor infiltrating CD8 positive lymphocytes.

RESULTS

At a cut-off level of 10% positive tumor cells, PD-L1 positivity was seen in 85 of 118 (72%) tumor types, including thymoma (100% positive), Hodgkin's lymphoma (93%), anaplastic thyroid carcinoma (76%), Kaposi sarcoma (71%), sarcomatoid urothelial carcinoma (71%), and squamous cell carcinoma of the penis (67%), cervix (65%), floor of the mouth (61%), the lung (53%), and pharynx (50%). In immune cells, PD-L1 positivity was detectable in 103 (87%) tumor types, including tumors of haematopoetic and lymphoid tissues (75% to 100%), Warthin tumors of the parotid glands (95%) and Merkel cell carcinoma (82%). PD-L1 positivity in tumor cells was significantly correlated with the number of intratumoral CD8 positive lymphocytes across all tumor types as well as in individual tumor types, including serous carcinoma of the ovary, invasive breast carcinoma of no special type, intestinal gastric adenocarcinoma, and liposarcoma (p< 0.0001 each).

CONCLUSIONS

PD-L1 expression in tumor and inflammatory cells is found in a wide range of human tumor types. Higher rates of tumor infiltrating CD8 positive lymphocytes in PD-L1 positive than in PD-L1 negative cancers suggest that the antitumor immune response may trigger tumoral PD-L1 expression.

NUTM1 -rearranged Carcinoma of the Thyroid : A Distinct Subset of NUT Carcinoma Characterized by Frequent NSD3 - NUTM1 Fusions

NUT carcinoma (NC) is a rare subtype of squamous cell carcinoma defined by NUTM1 rearrangements encoding NUT fusion oncoproteins (the most frequent fusion partner being BRD4 ) that carries a very poor prognosis, with most patients dying in under 1 year. Only rare primary thyroid NCs have been reported. Here, we evaluated a series of 14 cases. The median patient age at diagnosis was 38 years (range: 17 to 72 y). Eight of 13 cases with slides available for review (62%) showed a morphology typical of NC, whereas 5 (38%) had a non-NC-like morphology, some of which had areas of cribriform or fused follicular architecture resembling a follicular cell-derived thyroid carcinoma. For cases with immunohistochemistry results, 85% (11/13) were positive for NUT on biopsy or resection, though staining was significantly decreased on resection specimens due to fixation; 55% (6/11) were positive for PAX8, and 54% (7/13) for TTF-1. Tumors with a non-NC-like morphology were all positive for PAX8 and TTF-1. The fusion partner was known in 12 cases: 9 (75%) cases had a NSD3-NUTM1 fusion, and 3 (25%) had a BRD4-NUTM1 fusion. For our cohort, the 2-year overall survival (OS) was 69%, and the 5-year OS was 58%. Patients with NC-like tumors had a significantly worse OS compared with that of patients with tumors with a non-NC-like morphology ( P =0.0462). Our study shows that NC of the thyroid can mimic other thyroid primaries, has a high rate of NSD3 - NUTM1 fusions, and an overall more protracted clinical course compared with nonthyroid primary NC.

Systemic explanation of Glycyrrhiza glabra's analyzed compounds and anti-cancer mechanism based on network pharmacology in oral cancer

OBJECTIVES

Several studies suggest that Glycyrrhiza glabra (GG) extract could be a useful supplemental source for various cancer treatments. However, very few studies on oral cancer (OC) have been conducted. The present study was aimed at exploring the bioactive compounds (bioactives) along with the mode of action of GG against OC using network pharmacology.

METHODS

Liquid chromatography-mass spectrometry/mass spectrometry was used to identify and analyze compounds from GG. Public databases were used to identify genes associated with the selected bioactives and OC. With the help of Cytoscape software, the association between bioactive and common genes was built, visualized, and investigated. Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) was used to investigate protein-protein interactions for intergenic interactions. Finally, the pathway enrichment analysis of common genes was done using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) platform.

RESULTS

Overall, 378 bioactives were identified in GG. Using public databases, an entire 254 bioactive-related genes and 734 OC-related genes were recognized, with 48 common genes. Cytoscape analysis showed wortmannin as the key bioactive and androgen receptor as the hub gene. The DAVID results revealed that the significant mechanism of action of GG against OC may be to induce apoptosis of cancer cells by deactivating the PI3K-AKT signaling pathway.

CONCLUSION

The key active components and mechanisms of action of GG against OC were investigated. The present study provides scientific suggestions to support the clinical outcome of GG for OC along with a research foundation for additional elaboration on the important bioactives and mechanisms of GG against OC.

Prognostic role of HPV integration status and molecular profile in advanced anal carcinoma: An ancillary study to the epitopes-HPV02 trial

Squamous Cell Carcinoma of the Anal canal (SCCA) is a rare disease associated with a Human Papillomavirus (HPV) infection in most cases, predominantly the HPV16 genotype. About 15% of SCCA are diagnosed in metastatic stage and some will relapse after initial chemoradiotherapy (CRT). Treatment of patients by Docetaxel, Cisplatin and 5-fluorouracil (DCF) has been recently shown to improve their complete remission and progression-free survival. The aim of this retrospective study was to explore the impact of HPV infection, HPV DNA integration, TERT promoter mutational status and somatic mutations of oncogenes on both progression-free (PFS) and overall survivals (OS) of patients treated by DCF. Samples obtained from 49 patients included in the Epitopes-HPV02 clinical trial, diagnosed with metastatic or non-resectable local recurrent SCCA treated by DCF, were used for analyses. Median PFS and OS were not associated with HPV status. Patients with episomal HPV had an improved PFS compared with SCCA patients with integrated HPV genome (p=0.07). TERT promoter mutations were rarely observed and did not specifically distribute in a subset of SCCA and did not impact DCF efficacy. Among the 42 genes investigated, few gene alterations were observed, and were in majority amplifications (68.4%), but none were significantly correlated to PFS. As no biomarker is significantly associated with patients’ survival, it prompts us to include every patient failing CRT or with metastatic disease in DCF strategy.

PI3K Inhibition for Squamous Cell Head and Neck Carcinoma

ABSTRACT

The phosphoinositide 3-kinase (PI3K) pathway is aberrantly activated in most head and neck squamous cell carcinomas, making it a prized target for targeted therapy development. Multiple PI3K inhibitors have been studied in early phase trials, with unfavorable risk-benefit ratios in molecularly unselected patient populations. Buparlisib, a potent pan-class I PI3K inhibitor, shows promising efficacy in combination with paclitaxel for advanced head and neck squamous cell carcinoma. Results of the phase III BURAN trial are awaited.

Programmed Death Ligand-1 Expression Is Associated With Poorer Survival in Anal Squamous Cell Carcinoma

Context.—

Upregulation of programmed death ligand-1 (PD-L1), an immunoregulatory protein, is associated with an adverse outcome in several malignancies. Very few studies have evaluated PD-L1 expression in invasive anal squamous cell carcinoma (ASCC).

Objective.—

To assess PD-L1 expression in patients with ASCC and correlate it with clinicopathologic factors and clinical outcomes.

Design.—

Fifty-one cases of ASCC were immunostained for PD-L1. PD-L1 expression by combined positive score and tumor proportion score was correlated with age, gender, HIV status, HIV viral load, CD4 count, stage, and outcomes. Kaplan-Meier curves for overall survival were plotted and compared using the log-rank test. Cox regression analysis was performed to identify significant prognostic factors (2-tailed P &lt; .05 was considered statistically significant).

Results.—

PD-L1 was positive in 24 of 51 cases (47%) by combined positive score and in 18 of 51 (35%) by tumor proportion score. The median cancer-specific survival and 5-year overall survival were significantly lower in PD-L1+ patients. Age, gender, HIV status, HIV viral load, stage, and cancer progression were not significantly different between the two groups. CD4 count of more than 200/μL was significantly higher in PD-L1+ patients. PD-L1+ status remained statistically significant for worse overall survival on multivariate analysis.

Conclusions.—

PD-L1+ status is an independent adverse prognostic factor for overall survival in ASCC. This study highlights the potential of PD-L1 targeted therapy in better management of ASCC.

The Role of Immunotherapy in the Treatment of Advanced Cervical Cancer: Current Status and Future Perspectives

Cervical cancer remains one of the most common cancers in women around the world however therapeutic options in the advanced and recurrent setting are limited. Immune checkpoint inhibitors (ICI) have been considered an attractive option given the viral etiology of cervical cancer although the majority of patients do not benefit from their use. This review summarises current knowledge and use of immune checkpoint blockade in cervical cancer as well as discussing the challenges faced in their clinical application, namely, the role of biomarker-driven ICI use, potential mechanisms of resistance, strategies to overcome such resistance and additional immunotherapy options beyond ICI.

Lack of Conserved miRNA Deregulation in HPV-Induced Squamous Cell Carcinomas

Squamous cell carcinomas (SCCs) in the anogenital and head and neck regions are associated with high-risk types of human papillomaviruses (HR-HPV). Deregulation of miRNA expression is an important contributor to carcinogenesis. This study aimed to pinpoint commonly and uniquely deregulated miRNAs in cervical, anal, vulvar, and tonsillar tumors of viral or non-viral etiology, searching for a common set of deregulated miRNAs linked to HPV-induced carcinogenesis. RNA was extracted from tumors and nonmalignant tissues from the same locations. The miRNA expression level was determined by next-generation sequencing. Differential expression of miRNAs was calculated, and the patterns of miRNA deregulation were compared between tumors. The total of deregulated miRNAs varied between tumors of different locations by two orders of magnitude, ranging from 1 to 282. The deregulated miRNA pool was largely tumor-specific. In tumors of the same location, a low proportion of miRNAs were exclusively deregulated and no deregulated miRNA was shared by all four types of HPV-positive tumors. The most significant overlap of deregulated miRNAs was found between tumors which differed in location and HPV status (HPV-positive cervical tumors vs. HPV-negative vulvar tumors). Our results imply that HPV infection does not elicit a conserved miRNA deregulation in SCCs.

Recent insights in the PI3K/Akt pathway as a promising therapeutic target in combination with EGFR-targeting agents to treat head and neck squamous cell carcinoma

Resistance to therapies targeting the epidermal growth factor receptor (EGFR), such as cetuximab, remains a major roadblock in the search for effective therapeutic strategies in head and neck squamous cell carcinoma (HNSCC). Due to its close interaction with the EGFR pathway, redundant or compensatory activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway has been proposed as a major driver of resistance to EGFR inhibitors. Understanding the role of each of the main proteins involved in this pathway is utterly important to develop rational combination strategies able to circumvent resistance. Therefore, the current work reviewed the role of PI3K/Akt pathway proteins, including Ras, PI3K, tumor suppressor phosphatase and tensing homolog, Akt and mammalian target of rapamycin in resistance to anti-EGFR treatment in HNSCC. In addition, we summarize PI3K/Akt pathway inhibitors that are currently under (pre)clinical investigation with focus on overcoming resistance to EGFR inhibitors. In conclusion, genomic alterations in and/or overexpression of one or more of these proteins are common in both human papillomavirus (HPV)-positive and HPV-negative HNSCC tumors. Therefore, downstream effectors of the PI3K/Akt pathway serve as promising drug targets in the search for novel therapeutic strategies that are able to overcome resistance to anti-EGFR treatment. Co-targeting EGFR and the PI3K/Akt pathway can lead to synergistic drug interactions, possibly restoring sensitivity to EGFR inhibitors and hereby improving clinical efficacy. Better understanding of the predictive value of PI3K/Akt pathway alterations is needed to allow the identification of patient populations that might benefit most from these combination strategies.

Improved local control in p16 negative oropharyngeal cancers with hypermethylated MGMT

INTRODUCTION

Patients with oropharyngeal cancers that are p16 negative (p16-) have worse outcomes than those who are p16 positive (p16+) and there is an unmet need for prognostic markers in this population. O6-Methylguanine (O6-MG)-DNA-methyltransferase (MGMT) gene methylation has been associated with response to chemoradiotherapy (CRT) in glioblastoma. We sought to find if MGMT promoter methylation was associated with outcomes of locally advanced oropharyngeal and oral cavity squamous cell carcinoma (OOSCC) in patients treated with definitive concurrent CRT.

METHODS

Patients were identified with primary OOSCC, known p16 status, retrievable pre-treatment biopsies, and at least 6 months of follow-up who received definitive concurrent CRT from 2004 to 2015. Biopsies were tested for MGMT hypermethylation (MGMT+) using a Qiagen pyrosequencing kit (Catalog number 970061). Outcomes were subsequently recorded and analyzed.

RESULTS

Fifty-eight patients were included with a median follow up of 78 (range 6-196) months. Fourteen patients (24.1%) had oral cavity cancer and 44 (75.9%) had oropharyngeal cancer. A significant difference was found for local recurrence free survival (LRFS) by combined MGMT and p16 status (p = 0.0004). Frequency of LR in MGMT+/p16+, MGMT+/p16-, MGMT-/p16+, and MGMT-p16- patients was 14.3%, 14.3%, 13.0%, and 69.2%, respectively (p = 0.0019). A significant difference was not found for distant recurrence free survival (p = 0.6165) or overall survival (p = 0.1615). LRFS remained significant on analysis restricted to oropharyngeal cancer patients (p-value = 0.0038).

CONCLUSION

Patients who are p16- and MGMT+ with oropharyngeal and oral cavity squamous cell carcinoma have significantly better LC with definitive CRT than those who are p16- and MGMT-. Prospective studies are needed to verify these findings.

Molecular events in the pathogenesis of vulvar squamous cell carcinoma

Vulvar squamous cell carcinomas (VSCC), which constitute over 90% of vulvar malignancies in adults, are classifiable into 2 subgroups that are mostly clinicopathologically distinct, a classification that is fundamentally based whether or not the tumors are HPV-mediated. In this review, we aim to summarize the recent advances in the understanding of molecular events in the pathogenesis of VSCC, including common and targetable mutations, copy number alterations, epigenetics, noncoding RNAs, and tumor immune microenvironment, which may provide insight into the future management of the disease. These events show substantial differences between the 2 subgroups, although significant areas of overlap exist. Recurrent, driver mutations appear to be substantially more prevalent in HPV(-) VSCC. TP53 mutations are the most common somatic mutations in VSCC overall, and are notably predominant in the HPV(-) VSCC, where 30-88% show a mutation. TP53 mutations are associated with worse patient outcomes, and co-mutations between TP53 and either HRAS, PIK3CA or CDKN2A appear to define subsets with even worse outcomes. A wide variety of other somatic mutations have been identified, including a subset with different mutational frequencies between HPV(+) and HPV(-) VSCC. CDKN2A mutations are common, and have been identified in 21 to 55% of HPV(-) VSCC, and in 2 to 25% of HPV(+) VSCC. Hypermethylation of CDKN2A is the most frequently reported epigenetic alteration in VSCC and the expression of some microRNAs may be associated with patient outcomes. The PTEN/PI3K/AKT/mTOR pathway is commonly altered in HPV(+) VSCC, and is accordingly potentially targetable. HPV-positivity/p16 block expression by immunohistochemistry has been found to be an independent prognostic marker for improved survival in VSCC, and may have some predictive value in VSCC patients treated with definitive radiotherapy. 22-39.3% and 68% of VSCC show EGFR amplification and protein overexpression respectively, although the prognostic and predictive value of an EGFR alteration requires additional study. Recurrent chromosomal gains in VSCCs have been found at 1q, 2q, 3q, 4p, 5p, 7p, 8p, 8q, and 12q, and there may be differential patterns of alterations depending on HPV-status. At least one-third of VSCC patients may potentially benefit from immune checkpoint inhibition therapy, based on a high frequency of PD-L1 expression or amplification, or a high tumor mutational burden. Additional studies are ultimately required to better understand the global landscape of genetic and epigenetic alterations in VSCC, and to identify and test potential targets for clinical application.

An evaluation of buparlisib for the treatment of head and neck squamous cell carcinoma

INTRODUCTION

Five-year overall survival for head and neck squamous cell carcinoma (HNSCC) is relatively poor at around 50-66%, and there has been little improvement over the past several decades. PIK3CA alterations are common in HNSCC and offer a promising therapeutic target.

AREAS COVERED

The authors discuss the PIK3 pathway and the use of PIK3 inhibitors in cancer, with a particular focus on HNSCC. A summary of the safety and efficacy of buparlisib, a class I pan-PI3K inhibitor, from several phase I and phase II HNSCC trials is provided.

EXPERT OPINION

With a maximum tolerated dose of 100 mg/day and an acceptable toxicity profile, buparlisib may be effective in HNSCC, irrespective of PIK3CA mutational status. On-going clinical trials will help determine the developmental strategy of buparlisib while novel combinatory strategies including combination with immune checkpoint inhibitors should be considered. Importantly, biomarker strategies, including wider use of tumor sequencing and circulating tumor DNA, should be utilized to improve patient selection.

Squamous cell carcinoma of head and neck: what internists should know

Squamous cell carcinoma of head and neck (SCCHN) is a group of cancer arising from mucosal surfaces of the head and neck. Optimal management of SCCHN requires a multidisciplinary team of surgical oncologists, radiation oncologists, medical oncologists, nutritionist, and speech-language pathologists, due to the complexity of anatomical structure and importance of functional outcome. Human papilloma virus (HPV)-related SCCHN represents a distinct subset from HPV negative SCCHN which is associated with carcinogen exposure such as cigarette smoking, betel nut use and alcohol. HPV related SCCHN responds better to concurrent chemoradiation and has better overall prognosis, compared to HPV negative SCCHN. Radiation therapy has been introduced to the treatment of SCCHN, administered concurrently with systemic chemotherapy for locoregional SCCHN, as well as a palliative measure for recurrent and/or metastatic (R/M) SCCHN. Recently, immune checkpoint inhibitors have been shown to improve overall survival in R/M-SCCHN and have been incorporated into the standard of care. Combination approaches with immune therapy and targeted therapy for biomarker enriched population based on genomics are being actively investigated and will shape the future of SCCHN treatment.

Somatic Mutation Profiling in Premalignant Lesions of Vulvar Squamous Cell Carcinoma

Vulvar squamous cell carcinoma (VSCC) originates from the progression of either a high-grade squamous intraepithelial lesion (HSIL) or differentiated-type vulvar intraepithelial neoplasia (dVIN), often in a background of lichen sclerosus (LS). The mechanisms leading to the progression of these premalignant lesions to VSCC are elusive. This study aims to identify pathogenic mutations implicated in VSCC development. Using next-generation sequencing, 38 HSIL, 19 dVIN, 20 LS, of which 10 were solitary lesions and 10 with adjacent VSCC, and 10 VSCC adjacent to LS, were screened for hotspot mutations in 50 genes covered by the Ion AmpliSeq Cancer Hotspot Panel v2 Kit (Thermo Fisher Scientific). Pathogenic mutations of TP53 were the most common genetic alterations identified in 53% and 24% of dVIN and HSIL cases, respectively, followed by CDKN2A (p16) mutated in 42% and 0% of dVIN and HSIL, respectively. Seven (70%) and three (30%) of 10 cases of VSCC associated with LS carried TP53 and CDKN2A mutations, respectively, whereas neither solitary LS nor LS associated with VSCC cases harbored mutations in these genes. It appears that TP53 mutations are early events during VSCC carcinogenesis, being present in both HSIL and dVIN lesions. Our preliminary data do not support a genetic background for the notion of LS as the VSCC premalignant lesion.

The molecular pathogenesis of Trichilemmal carcinoma

BACKGROUND

Trichilemmal carcinoma (TC) is an extremely rare hair follicle tumor. We aimed to explore the genetic abnormalities involved in TC to gain insight into its molecular pathogenesis.

METHODS

Data from patients diagnosed with TC within a 12-year period were retrospectively reviewed. Genomic DNA isolated from a formalin-fixed paraffin-embedded (FFPE) tumor tissue block was sequenced and explored for a panel of cancer genes.

RESULTS

DNA was extracted from the FFPE tissue of four patients (50% female; mean age, 51.5 years) diagnosed with TC for analysis. The tumor was located in the head and neck of three patients and in the shoulder of one patient. TP53 mutations (p.Arg213*, p.Arg249Trp, and p.Arg248Gln) were found in three patients. Fusions previously identified in melanoma were detected in two patients (TACC3-FGFR3 and ROS1-GOPC fusions). Other mutations found included NF1-truncating mutation (Arg1362*), NRAS mutation (p.Gln61Lys), TOP1 amplification, and PTEN deletion. Overall, genetic changes found in TC resemble that of other skin cancers, suggesting similar pathogenesis. All patients with TP53 mutations had aggressive clinical course, two who died (OS 93 and 36 months), and one who experienced recurrent relapse.

CONCLUSIONS

We reported the genomic variations found in TC, which may give insight into the molecular pathogenesis. Overall, genetic changes found in TC resembled that of other skin cancers, suggesting similar pathogenesis. TP53 mutations was were identified in patients who had an aggressive clinical course. Genetic alterations identified may further suggest the potential treatment options of TC.

Distinguishing between HPV-Associated Metastatic Anal Squamous Cell Cancer and HPV-Associated Oropharyngeal Cancer

The histology and immunohistochemistry (IHC) of primary and metastatic diseases from a human papilloma virus- (HPV-) related anal squamous carcinoma (ASCC) would typically demonstrate the same histology as an HPV-related oropharyngeal squamous carcinoma (OPSCC). However, determining whether a site of squamous cell carcinoma represents distant metastatic ASCC versus a metastatic HPV-related metastasis from an OPSCC to a regional lymph node carries profound prognostic and therapeutic implications. A patient with a history of locally advanced ASCC treated with standard concurrent radiation therapy and chemotherapy in 2015 is described. In 2018, an enlarged supraclavicular lymph node was excised demonstrating squamous cell carcinoma and radiographic staging revealed no other areas suspicious for malignancy. Direct laryngoscopy with operating telescope and biopsies demonstrated squamous cell carcinoma at the tongue base. Described here are assays that might be considered in distinguishing between whether a focus distant from a previously identified ASCC represents metastatic disease or instead a separate primary HPV-related cancer.

Potential targets for tumor-specific imaging of vulvar squamous cell carcinoma: A systematic review of candidate biomarkers

INTRODUCTION

Vulvar squamous cell carcinoma (VSCC) is a rare malignancy with an increasing incidence, especially in young women. Surgical treatment of VSCC is associated with significant morbidity and high recurrence rates, which is related to the limited ability to distinguish (pre)malignant from healthy tissue. There is a need for new tools for specific real-time detection of occult tumor lesions and localization of cancer margins in patients with VSCC. Several tumor-specific imaging techniques are developed to recognize malignant tissue by targeting tumor markers. We present a systematic review to identify, evaluate, and summarize potential markers for tumor-specific imaging of VSCC.

METHODS

Relevant papers were identified by a systematic cross-database literature search developed with assistance of an experienced librarian. Data were extracted from eligible papers and reported based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. VSCC-specific tumor markers were valued based on a weighted scoring system, in which each biomarker was granted points based on ranked eligibility criteria: I) percentage expression, II) sample size, and III) in vivo application.

RESULTS

In total 627 papers were included of which 22 articles met the eligibility criteria. Twelve VSCC-specific tumor markers were identified and of these 7 biomarkers were considered most promising: EGFR, CD44v6, GLUT1, MRP1, MUC1, CXCR-4 and VEGF-A.

DISCUSSION

This overview identified 7 potential biomarkers that can be used in the development of VSCC-specific tracers for real-time and precise localization of tumor tissue before, during, and after treatment. These biomarkers were identified in a small number of samples, without discriminating for VSCC-specific hallmarks such as HPV-status. Before clinical development, experimental studies should first aim at validation of these biomarkers using immunohistochemistry and cell line-based examination, discriminating for HPV-status and the expression rate in lymph nodes and precursor lesions.

PTEN and Gynecological Cancers

PTEN is a tumour suppressor gene, and its loss of function is frequently observed in both heritable and sporadic cancers. It is involved in a great variety of biological processes, including maintenance of genomic stability, cell survival, migration, proliferation and metabolism. A better understanding of PTEN activity and regulation has therefore emerged as a subject of primary interest in cancer research. Gynaecological cancers are variously interested by PTEN deregulation and many perspective in terms of additional prognostic information and new therapeutic approaches can be explored. Here, we present the most significant findings on PTEN in gynaecological cancers (ovarian, endometrial, cervical, vulvar and uterine cancer) focusing on PTEN alterations incidence, biological role and clinical implications.

Absence of disruptive TP53 mutations in high-risk human papillomavirus-driven neck squamous cell carcinoma of unknown primary

BACKGROUND

To enforce the evidence for causality between high-risk human papillomavirus (hrHPV) infections and neck squamous cell carcinoma from unknown primary (NSCCUP) and provide biological basis for treatment de-intensification, we searched for TP53 mutations in association with HPV status.

METHODS

TP53 mutations were searched for by amplification of exons 4 to 10.

RESULTS

Of the 70 NSCCUP, 27 (39%) harbored HPV infection. TP53 sequencing resulted in the identification of 19 patients harboring single mutations including 16 disruptive alterations (84%). The association of TP53 mutations and HPV could be evaluated in 48 NSCCUP including those with disruptive mutation in any exon (n = 16) and those without mutations but with complete sequence of exons 4 to 9 (n = 32): no disruptive mutations were found in the 17 HPV-driven NSCCUP but in 16 of the 31 non-HPV-driven NSCCUP (P = .0002).

CONCLUSION

In a fraction of cases, NSCCUP is an HPV-driven entity harboring wild-type TP53 gene or nondisruptive TP53 mutations. HPV-driven NSCCUP might benefit from treatment de-intensification.

The Role of Biomarkers for the Prediction of Response to Checkpoint Immunotherapy and the Rationale for the Use of Checkpoint Immunotherapy in Cervical Cancer

Checkpoint immunotherapy has revolutionised the way that melanoma is treated and has also shown significant effectiveness in lung, bladder, renal, and head and neck cancers. At the present time, trials of checkpoint immunotherapy in cervical cancer are at early phases, but there is very good rationale for pursuing this as a treatment option, especially as cervical cancer is a virally driven cancer and therefore should be recognised by the immune system as being foreign. This review explores the biomarkers for the selection of patients for immunotherapy in other cancers, such as programmed death ligand 1 (PD-L1) expression, tumour infiltrating lymphocytes and total mutational burden, and relates these biomarkers to cervical cancer. A PubMed search was carried out for publications published in English with the terms 'immunotherapy' OR 'cervical cancer' OR 'checkpoint blockade' OR 'tumour infiltrating lymphocytes' OR 'total mutational burden'. Articles that met these criteria and were available on PubMed before 8 October 2018 were included. The results showed that PD-L1 is positive in up to 90% of cervical cancers and that the total mutational burden is moderately high, with 5-6 mutations per megabase. In addition, the tumour microenvironment in cervical cancer has an impact on prognosis, with higher ratios of CD8+ tumour infiltrating lymphocytes to CD4+ T regulatory cells being associated with improved survival. Clinical studies to date have shown the response rate of cervical cancer to checkpoint immunotherapy to be in the region to 10-25%. Cervical cancer exhibits many of the features that have been shown to be correlated with response to checkpoint immunotherapy in other tumour sites. However, response rates to date are in the region of 10-25%. Therefore, combinations of immunotherapeutic agents or checkpoint inhibitors with radiotherapy may be required to maximise the therapeutic benefit of harnessing the host immune system to fight cancer.

Mutation of chromatin regulators and focal hotspot alterations characterize human papillomavirus-positive oropharyngeal squamous cell carcinoma

BACKGROUND

Human papillomavirus (HPV)-associated oropharyngeal cancer is a disease clinically and biologically distinct from smoking-related head and neck squamous cell carcinoma (HNSCC). Despite its rapidly increasing incidence, the mutational landscape of HPV+ oropharyngeal squamous cell carcinoma (OPSCC) remains understudied.

METHODS

This article presents the first mutational analysis of the 46 HPV+ OPSCC tumors within the newly expanded cohort of 530 HNSCC tumors from The Cancer Genome Atlas. A separate exome sequencing analysis was also performed for 46 HPV+ OPSCCs matched to their normal lymphocyte controls from the Johns Hopkins University cohort.

RESULTS

There was a strikingly high 33% frequency of mutations within genes associated with chromatin regulation, including mutations in lysine methyltransferase 2C (KMT2C), lysine methyltransferase 2D (KMT2D), nuclear receptor binding SET domain protein 1 (NSD1), CREB binding protein (CREBBP), E1A-associated protein p300 (EP300), and CCCTC-binding factor (CTCF). In addition, the commonly altered genes phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA) and fibroblast growth factor receptor 3 (FGFR3) showed distinct domain-specific hotspot mutations in comparison with their HPV- counterparts. PIK3CA showed a uniquely high rate of mutations within the helicase domain, and FGFR3 contained a predominance of hotspot S249C alterations that were not found in HPV- HNSCC.

CONCLUSIONS

This analysis represents one of the largest studies to date of HPV+ OPSCC and lends novel insight into the genetic landscape of this biologically distinct disease, including a high rate of mutations in histone- and chromatin-modifying genes, which may offer novel therapeutic targets.

Selected Office Based Anticancer Treatment Strategies

Over the years, the treatment of patients with cancer has varied widely as much because of recent advancements in science and medicine as the philosophies that belie their use. This paper briefly describes many of the prevailing approaches in use today with an attempt to offer some perspective of how to apply these disparate methodologies so that they may be more effectively integrated, resulting in consistently better clinical responses.

HPV-Associated Oropharyngeal Cancer in the HIV/AIDS Patient

Since their discovery as the etiologic agents of cervical cancer in the mid-1970s, human papillomaviruses (HPVs) have been linked with a growing number of epithelial-derived tumors, including head and neck squamous cell carcinomas. HPV demonstrates a particular predilection for causing tumors of the oropharynx, with the majority of cases involving infection with high-oncogenic risk HPV-16. People living with HIV are at increased risk of infection with HPV- and HPV-related oral complications even with adequate control of their HIV infection with antiretroviral therapy. In this chapter, we discuss the molecular mechanisms that underlie HPV-mediated oncogenesis in the oropharynx. We also describe the progress that has been made in understanding the epidemiology of oral HPV infection and the determinants of oral HPV-related pathology. Finally, we examine what can be done to treat and prevent oral HPV infection, benign lesions, and cancer, particularly in the context of the HIV-positive patient.

Activating Mutations in Pik3ca Contribute to Anal Carcinogenesis in the Presence or Absence of HPV-16 Oncogenes

PURPOSE

Over 95% of human anal cancers are etiologically associated with high-risk HPVs, with HPV type 16 (HPV16) the genotype most commonly found. Activating mutations in the catalytic subunit of Phosphatidylinositol (3,4,5)-trisphosphate kinase (PI3K), encoded by the Pik3ca gene, are detected in approximately 20% of human anal cancers.Experimental Design: We asked if common activating mutations in Pik3ca contribute to anal carcinogenesis using an established mouse model for anal carcinogenesis in which mice are topically treated with the chemical carcinogen 7,12-Dimethylbenz(a)anthracene (DMBA). Mice expressing in their anal epithelium one of two activating mutations in Pik3ca genes, Pik3ca^H1047R or Pik3ca^E545K , were monitored for anal carcinogenesis in the presence or absence of transgenes expressing the HPV16 E6 and E7 oncogenes.

RESULTS

Both mutant forms of Pik3ca increased susceptibility to anal carcinogenesis in the absence of HPV16 oncogenes, and cooperated with HPV16 oncogenes to induce the highest level and earliest onset of anal cancers. The combination of HPV16 oncogenes and Pik3ca mutations led to anal cancers even in the absence of treatment with DMBA. We further observed that the investigational mTOR1/2 dual inhibitor, TAK-228, significantly reduced the size of anal cancer-derived tumor spheroids in vitro and reduced the growth rates of anal cancer-derived tumor grafts in vivo.

CONCLUSIONS

These data demonstrate that activating mutations in Pik3ca drive anal carcinogenesis together with HPV16 oncogenes, and that the PI3K/mTOR pathway is a relevant target for therapeutic intervention.

Increased risk of second cancers at sites associated with HPV after a prior HPV-associated malignancy, a systematic review and meta-analysis

Background

High-risk human papilloma viruses (HPV) are a causative agent of anogenital and oropharyngeal cancers. Patients treated for a preinvasive or invasive HPV-associated cancer may be at increased risk of a second such malignancy.

Methods

We performed a systematic review and random effects meta-analysis to estimate the risk of HPV-associated cancer after prior diagnosis. Studies reporting second cancers at anogenital and oropharyngeal sites after prior diagnoses (preinvasive/invasive HPV-associated cancer) were identified. Studies reporting standardised incidence ratios (SIRs) were included in formal meta-analyses of second cancer risk. (PROSPERO ID: CRD42016046974).

Results

Searches returned 5599 titles, including 60 unique, eligible studies. Thirty-two (98 comparisons) presented SIRs for second cervical, anal, vulvo-vaginal, penile, and/or oropharyngeal cancers, included in the meta-analyses. All studies (and 95/98 comparisons) reported increased cancers in the population with previous HPV-associated cancer when compared to controls. Pooled SIRs for second primary cancers ranged from 1.75 (95% CI 0.66−4.67) for cervical cancer after primary anal cancer, to 13.69 (95% CI 8.56−21.89) for anal cancer after primary vulvo-vaginal cancer.

Conclusions

We have quantified the increased risk of second HPV-associated cancer following diagnosis and treatment for initial cancer or preinvasive disease. This has important implications for follow-up, screening, and future therapeutic trials.

Targeting phosphoinositide 3-kinase (PI3K) in head and neck squamous cell carcinoma (HNSCC)

The landscape of head and neck squamous cell carcinoma (HNSCC) has been changing rapidly due to growing proportion of HPV-related disease and development of new therapeutic agents. At the same time, there has been a constant need for individually tailored treatment based on genetic biomarkers in order to optimize patient survival and alleviate treatment-related toxicities. In this regard, aberrations of PI3K pathway have important clinical implications in the treatment of HNSCC. They frequently constitute ‘gain of function’ mutations which trigger oncogenesis, and PI3K mutations can also lead to emergence of drug resistance after treatment with EGFR inhibitors. In this article, we review PI3K pathway as a target of treatment for HNSCC and summarize PI3K/mTOR inhibitors that are currently under clinical trials. In light of recent advancement of immune checkpoint inhibitors, consideration of PI3K inhibitors as potential immune modulators is also suggested.

Identification of key pathways and genes in the progression of cervical cancer using bioinformatics analysis

The aim of the present study was to investigate the key pathways and genes in the progression of cervical cancer. The gene expression profiles GSE7803 and GSE63514 were obtained from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified using GEO2R and the limma package, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted using the Database for Annotation, Visualization and Integrated Discovery. The hub genes were identified using Cytoscape and protein-protein interaction (PPI) networks were constructed using the STRING database. A total of 127 and 99 DEGs were identified in the pre-invasive and invasive stages of cervical cancer, respectively. GO enrichment analysis indicated that the DEGs in pre-invasive cervical cancer were primarily associated with the ‘protein binding’, ‘single-stranded DNA-dependent ATPase activity’, ‘DNA replication origin binding’ and ‘microtubule binding’ terms, whereas the DEGs in invasive cervical cancer were associated with the ‘extracellular matrix (ECM) structural constituent’, ‘heparin binding’ and ‘integrin binding’. KEGG enrichment analysis revealed that the pre-invasive DEGs were significantly enriched in the ‘cell cycle’, ‘DNA replication’ and ‘p53 signaling pathway’ terms, while the invasive DEGs were enriched in the ‘amoebiasis’, ‘focal adhesion’, ‘ECM-receptor interaction’ and ‘platelet activation’ terms. The PPI network identified 4 key genes (PCNA, CDK2, VEGFA and PIK3CA), which were hub genes for pre-invasive and invasive cervical cancer. In conclusion, bioinformatics analysis identified 4 key genes in cervical cancer progression (PCNA, CDK2, VEGFA and PIK3CA), which may be potential biomarkers for differentiating normal cervical epithelial tissue from cervical cancer.

Somatic Host Cell Alterations in HPV Carcinogenesis

High-risk human papilloma virus (HPV) infections cause cancers in different organ sites, most commonly cervical and head and neck cancers. While carcinogenesis is initiated by two viral oncoproteins, E6 and E7, increasing evidence shows the importance of specific somatic events in host cells for malignant transformation. HPV-driven cancers share characteristic somatic changes, including apolipoprotein B mRNA editing catalytic polypeptide-like (APOBEC)-driven mutations and genomic instability leading to copy number variations and large chromosomal rearrangements. HPV-associated cancers have recurrent somatic mutations in phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) and phosphatase and tensin homolog (PTEN), human leukocyte antigen A and B (HLA-A and HLA-B)-A/B, and the transforming growth factor beta (TGFβ) pathway, and rarely have mutations in the tumor protein p53 (TP53) and RB transcriptional corepressor 1 (RB1) tumor suppressor genes. There are some variations by tumor site, such as NOTCH1 mutations which are primarily found in head and neck cancers. Understanding the somatic events following HPV infection and persistence can aid the development of early detection biomarkers, particularly when mutations in precancers are characterized. Somatic mutations may also influence prognosis and treatment decisions.

Comparative molecular profiling of HPV-induced squamous cell carcinomas

Approximately 5% of all cancer incidences result from human papillomavirus (HPV) infection. HPV infection most commonly leads to cancers of the anogenital region or oropharynx. It is unknown whether different HPV-mediated cancers collectively share a molecular signature and it is important to determine if there are targetable alterations common to different types of HPV-positive tumors. We analyzed 743 p53 wild-type samples of anal, cervical, oropharyngeal, and vulvar squamous cell carcinomas which underwent multiplatform testing at a commercial molecular profiling service. Expression of 24 proteins was measured by immunohistochemistry (IHC), mutation of 48 genes was determined by next-generation and Sanger sequencing, and copy number alteration for six genes was determined by in situ hybridization. The four cohorts had remarkably similar molecular profiles. No gene had a statistically significant difference in mutation frequency or copy number change between the four different types of squamous cell carcinomas. The only significant differences between cohorts were frequency of ERCC1 and SPARC loss as determined by IHC. In all four cancer types, oncogene mutation and PD-L1 expression was relatively infrequent. The most commonly mutated gene was PIK3CA, with mutations most often affecting the helical domain of the protein and accompanied by concurrent lack of PTEN expression. Loss of MGMT and RRM1 was common among the four cohorts and may be predictive of response to cytotoxic therapies not currently being used to treat these cancer types. The similar molecular profiles of the four cohorts indicate that treatment strategies may be similarly efficacious across HPV-positive cancers.