Modulation of therapeutic sensitivity by human papillomavirus

The value of subcutaneous xenografts for individualised radiotherapy in HNSCC: Robust gene signature correlates with radiotherapy outcome in patients and xenografts

PURPOSE

To assess the robustness of prognostic biomarkers and molecular tumour subtypes developed for patients with head and neck squamous cell carcinoma (HNSCC) on cell-line derived HNSCC xenograft models, and to develop a novel biomarker signature by combining xenograft and patient datasets.

MATERIALS AND METHODS

Mice bearing xenografts (n = 59) of ten HNSCC cell lines and a retrospective, multicentre patient cohort (n = 242) of the German Cancer Consortium-Radiation Oncology Group (DKTK-ROG) were included. All patients received postoperative radiochemotherapy (PORT-C). Gene expression analysis was conducted using GeneChip Human Transcriptome Arrays. Xenografts were stratified based on their molecular subtypes and previously established gene classifiers. The dose to control 50 % of tumours (TCD50) was compared between these groups. Using differential gene expression analyses combining xenograft and patient data, a gene signature was developed to define risk groups for the primary endpoint loco-regional control (LRC).

RESULTS

Tumours of mesenchymal subtype were characterized by a higher TCD50 (xenografts, p < 0.001) and lower LRC (patients, p < 0.001) compared to the other subtypes. Similar to previously published patient data, hypoxia- and radioresistance-related gene signatures were associated with high TCD50 values. A 2-gene signature (FN1, SERPINE1) was developed that was prognostic for TCD50 (xenografts, p < 0.001) and for patient outcome in independent validation (LRC: p = 0.007).

CONCLUSION

Genetic prognosticators of outcome for patients after PORT-C and subcutaneous xenografts after primary clinically relevant irradiation show similarity. The identified robust 2-gene signature may help to guide patient stratification, after prospective validation. Thus, xenografts remain a valuable resource for translational research towards the development of individualized radiotherapy.

Improving the efficacy of combined radiotherapy and immunotherapy: focusing on the effects of radiosensitivity

Cancer treatment is gradually entering an era of precision, with multitude studies in gene testing and immunotherapy. Tumor cells can be recognized and eliminated by the immune system through the expression of tumor-associated antigens, but when the cancer escapes or otherwise suppresses immunity, the balance between cancer cell proliferation and immune-induced cancer cell killing may be interrupted, resulting in tumor proliferation and progression. There has been significant attention to combining conventional cancer therapies (i.e., radiotherapy) with immunotherapy as opposed to treatment alone. The combination of radio-immunotherapy has been demonstrated in both basic research and clinical trials to provide more effective anti-tumor responses. However, the absolute benefits of radio-immunotherapy are dependent on individual characteristics and not all patients can benefit from radio-immunotherapy. At present, there are numerous articles about exploring the optimal models for combination radio-immunotherapy, but the factors affecting the efficacy of the combination, especially with regard to radiosensitivity remain inconclusive. Radiosensitivity is a measure of the response of cells, tissues, or individuals to ionizing radiation, and various studies have shown that the radiosensitivity index (RSI) will be a potential biomarker for predicting the efficacy of combination radio-immunotherapy. The purpose of this review is to focus on the factors that influence and predict the radiosensitivity of tumor cells, and to evaluate the impact and predictive significance of radiosensitivity on the efficacy of radio-immunotherapy combination.

HPV and radiosensitivity of cervical cancer: a narrative review

Background and Objective

Cervical cancer (CC), the most common gynecological malignancy, is divided into two categories: human papillomavirus-related [HPV positive (HPV+)] and non-HPV-related [HPV negative (HPV-)]. Compared with HPV- CC, HPV+ CC has better radiosensitivity and prognosis. We conducted a literature search and summarized relevant studies to explore the detailed mechanisms by which HPV+ improves the prognosis of CC compared to HPV-.

Methods

PubMed was used to search the literature on human papillomavirus, cervical cancer, and radiotherapy up to June 2022.

Key Content and Findings

Compared with HPV- CC, HPV+ CC has better radiotherapy outcomes and better prognosis. HPV improves the radiotherapy sensitivity of CC by inhibiting damaged DNA repair, increasing cell cycle arrest, reducing hypoxia, increasing cellular immune response, and other mechanisms. However, the effect of HPV on radiotherapy sensitivity of CC is not consistent and is affected by HPV type, viral load, and many other factors. Partial HPV+ CCs, due to hypoxia and other factors, are resistant to radiotherapy and have a poor prognosis. HPV- CC has poor radiotherapy sensitivity and poor prognosis. With the spread of the vaccine, HPV- CC will gradually increase, which is a cause for concern.

Conclusions

The radiosensitivity was significantly increased in patients with HPV+ CC, compared to HPV- patients. HPV improves the radiotherapy sensitivity of cervical cancer through a number of pathways. Meanwhile, the relationship between HPV and radiotherapy sensitivity is influenced by a number of factors. Some HPV+ CCs showed radiotherapy resistance, and HPV- CCs deserve further attention.

Analyses of molecular subtypes and their association to mechanisms ofradioresistance in patients with HPV-negative HNSCC treated bypostoperative radiochemotherapy

PURPOSE

To assess the relation of the previously reported classification of molecular subtypes to the outcome of patients with HNSCC treated with postoperative radio(chemo)therapy (PORT-C), and to assess the association of these subtypes with gene expressions reflecting known mechanisms of radioresistance.

MATERIAL AND METHODS

Gene expression analyses were performed using the GeneChip Human Transcriptome Array 2.0 on a multicentre retrospective patient cohort (N=128) of the German Cancer Consortium Radiation Oncology Group (DKTK-ROG) with locally advanced HNSCC treated with PORT-C. Tumours were assigned to four molecular subtypes, and correlation analyses between subtypes and clinical risk factors were performed. In addition, the classifications of eight genes or gene signatures related to mechanisms of radioresistance, which have previously shown an association with outcome of patients with HNSCC, were compared between the molecular subtypes. The endpoints loco-regional control (LRC) and overall survival (OS) were evaluated by log-rank tests and Cox regression.

RESULTS

Tumours were classified into the four subtypes basal (19.5%), mesenchymal (18.8%), atypical (15.6%) and classical (14.1%). The remaining tumours could not be classified (32.0%). Tumours of the mesenchymal subtype showed a lower LRC compared to the other subtypes (p=0.012). These tumours were associated with increased epithelial-mesenchymal transition (EMT) and overexpression of a gene signature enriched in DNA repair genes. The majority of the eight considered gene classifiers were significantly associated to LRC or OS in the whole cohort.

CONCLUSION

Molecular subtypes, previously identified on HNSCC patients treated with primary radio(chemo)therapy or surgery, were related to LRC for patients treated with PORT-C, where mesenchymal tumour presented with worse prognosis. After prospective validation, subtype-based patient stratification, potentially in combination with other molecular classifiers, may be considered in future interventional studies in the context of personalised radiotherapy and may guide the development of combined treatment approaches.

De-intensification strategies in HPV-related oropharyngeal squamous cell carcinoma-a narrative review

Human papillomavirus-related (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) is a relatively new clinical entity that is dramatically on the rise globally. HPV+ OPSCC is thought to be a separate clinical entity compared to HPV− OPSCC with a distinct tumor biology. Patients with HPV associated disease have been shown to have a substantially better prognosis and overall survival than those patients with the HPV negative (HPV−) counterpart. The standard of care for OPSCC is definitive radiation therapy (RT) and concurrent chemoradiation therapy (CRT), for lower and higher stage disease, respectively. However, traditional CRT is also associated with severe acute and late toxicities affecting patient quality of life, such as severe mucositis, dry mouth and dysphagia. Considering that HPV+ OPSCC is on the rise in a younger, healthier patient population and the good prognosis of HPV-related disease, there has been a focus on reducing treatment toxicities and optimizing quality of life while maintaining favorable oncologic outcomes. A variety of such de-escalation regimens are currently being explored in recently completed and ongoing clinical trials. Alterations to the standard chemotherapy, radiation and surgical regimens are being explored. This review will provide an overview of the rationale for and available results of the major de-intensification strategies in the treatment of locally advanced HPV+ OPSCC.

Co-incidence of Human Papillomaviruses and Epstein-Barr Virus Is Associated With High to Intermediate Tumor Grade in Human Head and Neck Cancer in Syria

High-risk human papillomaviruses (high-risk HPVs) have been recently reported to be co-present with Epstein–Barr virus (EBV) in different types of human cancers including head and neck (HN), where they can cooperate in the initiation and/or progression of this cancer. Accordingly, we herein explored the prevalence of high-risk HPVs and EBV in 80 HN cancer tissues from the Syrian population using polymerase chain reaction, immunohistochemistry, and tissue microarray methodologies. We report that high-risk HPVs and EBV are present in 35/80 (43.7%) and 41/80 (51.2%) of our samples, respectively, and the most frequent HPV types are 33, 16, 18, 45, 52, 58, 35, 51, and 31, in this order. More significantly, our data reveal that 25/80 (31.2%) of cancer cases are positive for high-risk HPVs as well as EBV, and their co-presence is associated with high/intermediate-grade squamous cell carcinomas. These data confirm the co-presence of high-risk HPVs and EBV in HN cancers in the Syrian population of the Middle East and demonstrate that their co-incidence is linked to a more aggressive cancer phenotype. Thus, future studies are required to confirm these data and elucidate the exact role of high-risk and EBV cooperation in human HN carcinogenesis.

Measurement of circulating free DNA in squamous cell carcinoma of the anus and relation to risk factors and recurrence

BACKGROUND

Measuring circulating-free-deoxyribonucleic-acid (cfDNA) has created a new framework for personalized treatment in oncology. The aim of this study was to analyze the relation between cfDNA and risk factors and outcome in squamous cell carcinoma of the anus (SCCA).

METHODS

Patients treated with radiotherapy for localized SCCA were included in Aarhus, Denmark from 2016 to 2019. Serum samples from baseline, during and after therapy, were measured for the level of cfDNA in copies per mL by a direct fluorescent assay.

RESULTS

Eighty patients were included. Samples were available at baseline (n = 73) mid-therapy (n = 74), end-therapy (n = 67) and one-year follow-up (1Y) (n = 29). P16-positivity was found in 89% (n = 55). The median level of cfDNA was higher for P16 negative tumors (1.48) compared with the P16 positive tumors (0.90, P = 0.04). Data showed a correlation between baseline cfDNA levels and Gross Tumor Volume (R² = 0.13, P < 0.01), and increasing levels with increasing T-stage (T1 = 0.80, T2 = 0.94, T3 = 1.11, T4 = 1.3). Higher cfDNA levels were observed in patients with poor performance status (P < 0.01). The cfDNA level decreased from baseline to mid-therapy (0.92-0.78, P < 0.01) and from baseline to 1Y (0.92-0.71, P < 0.01). Baseline levels for patients with treatment failure (n = 8) were above the 25th percentile (p = 0.05) which translates into difference in disease free survival.

CONCLUSION

Results indicate an association between baseline cfDNA levels and risk factors in SCCA and a low baseline level correlates to lower risk of treatment failure. Findings contribute with new knowledge of the biological role of cfDNA in SCCA and holds potential knowledge for personalized treatment of SCCA.

An Integrated Approach for Preventing Oral Cavity and Oropharyngeal Cancers: Two Etiologies with Distinct and Shared Mechanisms of Carcinogenesis

Head and neck squamous cell carcinoma (HNSCC) was the 7th most common malignancy worldwide in 2018 and despite therapeutic advances, the overall survival rate for oral squamous cell carcinoma (OSCC; ∼50%) has remained unchanged for decades. The most common types are OSCC and oropharyngeal squamous cell carcinoma (OPSCC, survival rate ∼85%). Tobacco smoking is a major risk factor of HNSCC. In the developed world, the incidence of OSCC is declining as a result of tobacco cessation programs. However, OPSCC, which is also linked to human papillomavirus (HPV) infection, is on the rise and now ranks as the most common HPV-related cancer. The current state of knowledge indicates that HPV-associated disease differs substantially from other types of HNSCC and distinct biological differences between HPV-positive and HPV-negative HNSCC have been identified. Although risk factors have been extensively discussed in the literature, there are multiple clinically relevant questions that remain unanswered and even unexplored. Moreover, existing approaches (e.g., tobacco cessation, vaccination, and chemoprevention) to manage and control this disease remain a challenge. Thus, in this review, we discuss potential future basic research that can assist in a better understanding of disease pathogenesis which may lead to novel and more effective preventive strategies for OSCC and OPSCC.

P16INK4A Immunohistochemistry as a Gold Standard for Cervical Cancer and Precursor Lesions Screening

BACKGROUND

High-risk (HR) Human papillomaviruses (HPVs) are known as the main factors implicated in the pathogenesis of cervical preinvasive and invasive lesions. Therefore, the presence or absence of HR-HPV can be followed for the prognosis of low-grade and high-grade squamous intraepithelial lesions. Since the overexpression of p16INK4a protein depends on the presence of transcriptionally-active HPV, and due to its availability and simple interpretation, it may be considered as a proper marker to diagnose cervical cancer.

METHODS

An immunohistochemical analysis of p16INK4a was performed in 72 cervical tissue specimens at Imam Khomeini Complex Hospital (Tehran, Iran) from 2016 to 2018. The performance parameters were calculated and compared using receiving operating characteristics curve (ROC) details.

RESULTS

p16INK4a is significantly up-regulated in the cervical cancer samples in comparison with that in normal samples. Moreover, the ROC data showed the potential ability of p16INK4a under determined conditions as a diagnostic marker for CIN 2-3 staging and invasive cervical cancer. The molecular typing disclosed the attendance of HPV DNA in 44.4% of cases (32/72) with a predominance of HPV type 16.

CONCLUSION

The molecular biomarker p16INK4a can be a good candidate for the early diagnosis and prognosis of cervical cancer in HPV-infected patients. Considering the increase in the expression level of p16INK4a in cancer and precancer tissues, p16INK4a may be used for early detection of cervical cancer.

Enhanced Radiation Sensitivity of Human Papillomavirus-Driven Head and Neck Cancer: Focus on Immunological Aspects

Head and neck squamous cell carcinomas (HNSCC), emerging in the mucosa of the upper aerodigestive tract, are associated with either the classical risk factors, tobacco and alcohol consumption, or with infections with high-risk types of the human papillomavirus (HPV). Depending on the involvement of HPV, HNSCC follow different pathways of carcinogenesis and show distinct clinical presentations regarding survival, prognosis and treatment response. For instance, HPV-driven HNSCC exhibit an enhanced radiation response compared to their typically radioresistant HPV-negative counterparts. Although radiosensitivity of HNSCC has been studied by many research groups, the major causes for the difference in radiation responses between HPV-driven and HPV-negative HNSCC are still an open question. In this mini review, we discuss the reported cellular and immunological factors involved in the enhanced radiation response in HPV-driven HNSCC, focusing on the vital role of the immune response in the outcome of HNSCC radiotherapy.

Phase II Evaluation of Aggressive Dose De-Escalation for Adjuvant Chemoradiotherapy in Human Papillomavirus-Associated Oropharynx Squamous Cell Carcinoma

PURPOSE

The purpose of this study was to determine if dose de-escalation from 60 to 66 Gy to 30 to 36 Gy of adjuvant radiotherapy (RT) for selected patients with human papillomavirus-associated oropharyngeal squamous cell carcinoma could maintain historical rates for disease control while reducing toxicity and preserving swallow function and quality of life (QOL).

PATIENTS AND METHODS

MC1273 was a single-arm phase II trial testing an aggressive course of RT de-escalation after surgery. Eligibility criteria included patients with p16-positive oropharyngeal squamous cell carcinoma, smoking history of 10 pack-years or less, and negative margins. Cohort A (intermediate risk) received 30 Gy delivered in 1.5-Gy fractions twice per day over 2 weeks along with 15 mg/m2 docetaxel once per week. Cohort B included patients with extranodal extension who received the same treatment plus a simultaneous integrated boost to nodal levels with extranodal extension to 36 Gy in 1.8-Gy fractions twice per day. The primary end point was locoregional tumor control at 2 years. Secondary end points included 2-year progression-free survival, overall survival, toxicity, swallow function, and patient-reported QOL.

RESULTS

Accrual was from September 2013 to June 2016 (N = 80; cohort A, n = 37; cohort B, n = 43). Median follow-up was 36 months, with a minimum follow-up of 25 months. The 2-year locoregional tumor control rate was 96.2%, with progression-free survival of 91.1% and overall survival of 98.7%. Rates of grade 3 or worse toxicity at pre-RT and 1 and 2 years post-RT were 2.5%, 0%, and 0%. Swallowing function improved slightly between pre-RT and 12 months post-RT, with one patient requiring temporary feeding tube placement.

CONCLUSION

Aggressive RT de-escalation resulted in locoregional tumor control rates comparable to historical controls, low toxicity, and little decrement in swallowing function or QOL.

Modulation of radiation sensitivity and antitumor immunity by viral pathogenic factors: Implications for radio-immunotherapy

Several DNA viruses including Human Papillomavirus (HPV), Epstein-Barr virus (EBV), and Human cytomegalovirus (HCMV) are mechanistically associated with the development of human cancers (HPV, EBV) and/or modulation of the immune system (HCMV). Moreover, a number of distinct mechanisms have been described regarding the modulation of tumor cell response to ionizing radiation and evasion from the host immune system by viral factors. There is further accumulating interest in the treatment with immune-modulatory therapies such as immune checkpoint inhibitors for malignancies with a viral etiology. Also, patients with HPV-positive tumors have a significantly improved prognosis that is attributable to increased intrinsic radiation sensitivity and may also arise from modulation of a cytotoxic T cell response in the tumor microenvironment (TME). In this review, we will highlight recent advances in the understanding of the biological basis of radiation response mediated by viral pathogenic factors and evasion from and modulation of the immune system by viruses.

Margin Analysis: Squamous Cell Carcinoma of the Oropharynx

Because of the common shared risk factors of smoking and heavy alcohol consumption, literature involving oropharyngeal squamous cell carcinoma (OPSCC) is often combined with oral squamous cell carcinoma. Human papilloma virus is now confirmed to be a major risk factor of OPSCC with its distinct epidemiology and favorable treatment outcome. The impact of adjuvant chemoradiation in the setting of positive surgical margins remains unclear but is likely influenced by tumor biology. This article reviews the tumor biology of OPSCC and summarizes recent findings on outcomes following surgical treatment of OPSCC.

Biomarkers in anal cancer: from biological understanding to stratified treatment

Squamous cell carcinomas of the anus and anal canal represent a model of a cancer and perhaps the first where level 1 evidence supported primary chemoradiotherapy (CRT) in treating locoregional disease with curative intent. The majority of tumours are associated with infection with oncogenic subtypes of human papilloma virus and this plays a significant role in their sensitivity to treatment. However, not all tumours are cured with CRT and there remain opportunities to improve outcomes in terms of oncological control and also reducing late toxicities. Understanding the biology of ASCC promises to allow a more personalised approach to treatment, with the development and validation of a range of biomarkers and associated techniques that are the focus of this review.

Independent validation of the prognostic value of cancer stem cell marker expression and hypoxia-induced gene expression for patients with locally advanced HNSCC after postoperative radiotherapy

OBJECTIVE

To validate the impact of HPV status, cancer stem cell (CSC) marker expression and tumour hypoxia status in patients with locally advanced head and neck squamous cell carcinoma (HNSCC), who received postoperative radiotherapy. The results of the exploration cohort have previously been reported by the German Cancer Consortium Radiation Oncology Group (DKTK-ROG; Lohaus et al., 2014; Linge et al., 2016).

MATERIALS AND METHODS

For 152 patients with locally advanced HNSCC the impact of HPV16 DNA status, CSC marker expression and hypoxia-associated gene signatures on outcome of postoperative radiotherapy were retrospectively analysed. Out of them, 40 patients received postoperative radiochemotherapy. Cox models presented in a previous study were validated using the concordance index as a performance measure. The primary endpoint of this study was loco-regional control. Results were compared to those previously reported by DKTK-ROG.

RESULTS

Loco-regional control, freedom from distant metastases and overall survival were inferior to the previously reported cohort. Despite of this, the prognostic value of the combination of HPV infection status, CSC marker expression (SLC3A2) and tumour hypoxia status could be validated in univariate analyses using an independent validation cohort. For multivariate models, the concordance index was between 0.58 and 0.69 in validation, indicating a good prognostic performance of the models. The inclusion of CD44 and the 15-gene hypoxia signature moderately improved the performance compared to a baseline model without CSC markers or hypoxia classifiers.

CONCLUSIONS

The HPV status, CSC marker expression of CD44 and SLC3A2 as well as hypoxia status are potential prognostic biomarkers for patients with locally advanced HNSCC treated by postoperative radiotherapy.