The impact of diabetes in head and neck cancer

Metformin radiosensitizes OSCC in 2D and 3D models: possible involvement of CAF-1

Objective

This study investigated metformin as a sensitizer for radiotherapy in oral squamous cell carcinoma (OSCC) to reduce the radiation intensity. It evaluated the drug's effect on Chromatin Assembly Factor-1 (CAF-1) expression, whose high levels correlate with worse prognosis of this cancer.

Methods

The effects of metformin, alone and with radiotherapy, were evaluated on CAL27 (HPV-) and SCC154 (HPV+) OSCC cells. The analyses were performed on cell monolayers by colony-forming assay, motility, and confocal microscopy. In spheroid 3D models, the sensitizing effect of metformin was assessed by measuring areas. CAF-1 expression affected by metformin was evaluated via Western blot, and its role was investigated by siRNAs.

Results

Metformin reduced the cells' ability to form colonies, migrate and invade, and promoted the acquisition of a less aggressive phenotype by increased E-cadherin and decreased N-cadherin expressions. Moreover, metformin lowered the IC50 of radiotherapy and showed strong effects on spheroid growth. Metformin downmodulated the expression of the major subunits of CAF-1, and the knockdown of this protein by siRNAs elicited a metformin-like effect on cell aggressiveness.

Conclusions

Metformin emerged as a promising adjuvant drug in OSCC because of its effects on cell aggressiveness and radiosensitizing action. These activities could be CAF-1-mediated.

The interplay between microbiome and host factors in pathogenesis and therapy of head and neck cancer

Heterogeneous cancers that lack strong driver mutations with high penetrance, such as head and neck squamous cell carcinoma (HNSCC), present unique challenges to understanding their aetiology due to the complex interactions between genetics and environmental factors. The interplay between lifestyle factors (such as poor oral hygiene, smoking, or alcohol consumption), the oral and gut microbiome, and host genetics appears particularly important in the context of HNSCC. The complex interplay between the gut microbiota and cancer treatment outcomes has also received increasing attention in recent years. This review article describes the bidirectional communication between the host and the oral/gut microbiome, focusing on microbiome-derived metabolites and their impact on systemic immune responses and the modulation of the tumour microenvironment. In addition, we review the role of host lifestyle factors in shaping the composition of the oral/gut microbiota and its impact on cancer progression and therapy. Overall, this review highlights the rationality of considering the oral/gut microbiota as a critical determinant of cancer therapy outcomes and points to therapeutic opportunities offered by targeting the oral/gut microbiota in the management of HNSCC.

Survivin/BIRC5 as a novel molecular effector at the crossroads of glucose metabolism and radioresistance in head and neck squamous cell carcinoma

BACKGROUND

Metabolic reprogramming and abnormal glucose metabolism are hallmarks of head and neck squamous cell carcinoma (HNSCC). Certain oncogenes can promote cancer-related metabolic changes, but understanding their crosstalk in HNSCC biology and treatment is essential for identifying predictive biomarkers and developing target therapies.

METHODS

We assessed the value of survivin/BIRC5 as a radioresistance factor potentially modulated by glucose for predicting therapeutic sensitivity and prognosis of HNSCC in a cohort of 32 patients. Additionally, we conducted in vitro experiments to explore the role of survivin/BIRC5 in glucose metabolism concerning radiation response.

RESULTS

Tumoral BIRC5 expression is associated with serum glucose and predicts locoregional disease-free survival and lower BIRC5 mRNA levels are associated with better outcomes. Upregulation of BIRC5 by radiation depends on glucose levels and provokes a pro-tumoral and radioresistant phenotype in surviving cells.

CONCLUSIONS

Survivin/BIRC5 might be independently associated with the risk of recurrence in patients with HNSCC.

Beneficial Effect of Metformin on the Five-Year Survival in about 40,000 Patients with Head and Neck Cancer

INTRODUCTION

Even in times of new therapy regimes, the overall survival of patients with head and neck cancer remains low. Since the previous studies showed the beneficial effect of metformin medication on the survival of patients with cancer, our objective was to investigate if-and in which way-metformin medication affects the overall survival of patients with head and neck cancer.

METHODS

Clinical data pertaining to patients diagnosed with head and neck cancer (International Classification of Diseases 10 codes C00-C14, C31, and C32) were retrospectively retrieved from the TriNetX network (TriNetX, Cambridge, MA, USA). The initial cohort extracted from the network was stratified into two groups: patients on metformin medication (cohort I), and individuals not on metformin medication (cohort II). The matching criteria included age, gender, BMI, type 2 diabetes, and risk factors, such as nicotine and alcohol abuse/dependence. Kaplan-Meier analysis, risk analysis, and the calculation of odds and hazard ratios were conducted. Additionally, the Hemoglobin A1c values were subject to analysis.

RESULTS

Following matching, each cohort comprised 20,416 patients. Cohort I exhibited a higher five-year survival rate at 75.3%, in contrast to cohort II, which registered a rate of 69.8%. The odds ratio was 0.79 (95% CI = 0.75-0.83), and the hazard ratio was 0.78 (95% CI = 0.75-0.82).

CONCLUSION

Metformin medication may correlate with improved five-year survival rates in patients with head and neck cancer. Since potentially influencing factors such as comorbidities and the initial tumor stage were not available, the results of our retrospectively conducted study must be interpreted with caution.

Prognostic value of diabetes and metformin use in a real-life population of head and neck cancer patients

Introduction

Head and neck carcinoma (HNC) is a disease with a poor prognosis despite currently available treatments. The management of patients with this tumor is often complicated by several comorbidities. Among these, diabetes is the second most frequent and its influence on the prognosis is not known.

Methods

In this work, we collected data on progression free survival (PFS) and overall survival (OS) of one hundred twenty-three patients with HNC who received biweekly cetuximab maintenance treatment after first-line chemotherapy. We then compared the survival of nondiabetic patients versus diabetics' one.

Results

Surprisingly, both PFS (4 vs. 5 months, HR 2.297, p < 0.0001) and OS (7 vs. 10 months, HR 3.138, p < 0.0001) were in favor of diabetic patients, even after excluding other clinical confounding factors. In addition, we also studied survivals in patients taking metformin, a widely used oral antidiabetic drug that has demonstrated antitumor efficacy in some cancers. Indeed, diabetic patients taking metformin had better PFS and OS than those not taking it, 7 vs. 5 months (HR 0.56, p = 0.0187) and 11 vs. 8.5 months (HR 0.53, p = 0.017), respectively.

Discussion

In conclusion, real-world outcomes of biweekly cetuximab maintenance remain comparable to clinical trials. The prognostic role of diabetes and metformin was confirmed to be significant in our series, but further prospective studies are needed for a definitive evaluation.

Blocking EREG/GPX4 Sensitizes Head and Neck Cancer to Cetuximab through Ferroptosis Induction

(1) Background: Epiregulin (EREG) is a ligand of EGFR and ErB4 involved in the development and the progression of various cancers including head and neck squamous cell carcinoma (HNSCC). Its overexpression in HNSCC is correlated with short overall survival and progression-free survival but predictive of tumors responding to anti-EGFR therapies. Besides tumor cells, macrophages and cancer-associated fibroblasts shed EREG in the tumor microenvironment to support tumor progression and to promote therapy resistance. Although EREG seems to be an interesting therapeutic target, no study has been conducted so far on the consequences of EREG invalidation regarding the behavior and response of HNSCC to anti-EGFR therapies and, more specifically, to cetuximab (CTX); (2) Methods: EREG was silenced in various HNSCC cell lines. The resulting phenotype (growth, clonogenic survival, apoptosis, metabolism, ferroptosis) was assessed in the absence or presence of CTX. The data were confirmed in patient-derived tumoroids; (3) Results: Here, we show that EREG invalidation sensitizes cells to CTX. This is illustrated by the reduction in cell survival, the alteration of cell metabolism associated with mitochondrial dysfunction and the initiation of ferroptosis characterized by lipid peroxidation, iron accumulation and the loss of GPX4. Combining ferroptosis inducers (RSL3 and metformin) with CTX drastically reduces the survival of HNSCC cells but also HNSCC patient-derived tumoroids; (4) Conclusions: The loss of EREG might be considered in clinical settings as a predictive biomarker for patients that might undergo ferroptosis in response to CTX and that might benefit the most from the combination of ferroptosis inducers and CTX.

Concentration of Selected Adipokines and Factors Regulating Carbohydrate Metabolism in Patients with Head and Neck Cancer in Respect to Their Body Mass Index

Head and neck cancers (HNCs) are a group of tumors not common in European populations. So far, not much is known about the role of obesity, adipokines, glucose metabolism, and inflammation in the pathogenesis of HNC. The aim of the study was to determine the concentrations of ghrelin, omentin-1, adipsin, adiponectin, leptin, resistin, visfatin, glucagon, insulin, C-peptide, glucagon-like peptide-1 (GLP-1), plasminogen activator inhibitor-1 (PAI-1), and gastric inhibitory peptide (GIP) in the blood serum of HNC patients depending on their body mass index (BMI). The study included 46 patients divided into two groups according to their BMI values: the normal BMI group (nBMI) included 23 patients with BMI < 25 kg/m² and the increased BMI group (iBMI) included patients with BMI ≥ 25 kg/m². A control group (CG) included 23 healthy people (BMI < 25 kg/m²). Statistically significant differences in the levels of adipsin, ghrelin, glucagon, PAI-1, and visfatin were shown between nBMI and CG. In the case of nBMI and iBMI, statistically significant differences were observed in the concentrations of adiponectin, C-peptide, ghrelin, GLP-1, insulin, leptin, omentin-1, PAI-1, resistin, and visfatin. The obtained results indicate a disruption of endocrine function of adipose tissue and impaired glucose metabolism in HNC. Obesity, which is not a typical risk factor for HNC, may aggravate the negative metabolic changes associated with this type of neoplasm. Ghrelin, visfatin, PAI-1, adipsin, and glucagon might be related to head and neck carcinogenesis. They seem to be promising directions for further research.

Effect of glycated hemoglobin A1c on the survival of patients with oral squamous cell carcinoma: A multi-institutional database cohort study

Objectives

Few studies have evaluated the impact of blood glucose levels on cancer prognosis. We investigated the association between hemoglobin A1c (HbA1c) and survival in oral squamous cell carcinoma (OSCC) patients.

Materials and Methods

A 19-year retrospective cohort study of OSCC patients was performed using the Chang Gung Research Database to identify and enroll 7279 patients diagnosed with OSCC between January 2001 and June 2020. A total of 3600 patients were recruited after performing 1:2 frequency-matching between patients with DM and non-DM. A Cox’s regression model was used to evaluate the relative hazards of all-cause mortality (ACM) and disease-specific mortality (DSM) in relation to HbA1c.

Results

An unadjusted Cox’s regression model indicated that DM, in addition to high levels of HbA1c, were statistically prognostic of poor survival. An adjusted hazard ratio (aHR) of HbA1c ≥ 8% interval at the initial diagnosis of OSCC was statistically higher for DSM (1.25 to 2.24) compared to the non-DM group in different regression models. Considering the effect of sustained HbA1c control in 699 patients, the aHR of mean HbA1c ≥ 9% interval was statistically higher for ACM (1.78 to 2.13) compared to the reference group (7% ≤ HbA1c< 8%). In addition, increased hazards of ACM (2.09 to 2.18) and DSM (2.20 to 2.41) were consistently observed in the highest quartiles of average real variability of HbA1c.

Conclusion

Poor and unstable control of HbA1c could strongly predict the risks of mortality in OSCC patients with DM.

Survival Benefit of Metformin as an Adjuvant Treatment for Head and Neck Cancer: A Systematic Review and Meta-Analysis

Background/Aims: The relationship between the efficacy of metformin and the prognosis of patients with head and neck cancer (HNC) was still unclear. This study aims to clarify the prognostic value of metformin treatment using meta-analysis.

Methods: Studies related to HNC prognosis and metformin were searched in Cochrane Library, Embase, LILACS, MEDLINE and PubMed databases. A meta-analysis was performed to evaluate the association between metformin therapy and the prognosis of HNC on overall survival (OS), disease-free survival (DFS) and disease-specific survival (DSS) and whether article quality, comorbidities, age, region or smoking had an influence on the prognosis of metformin treatment. Pooled hazard ratio (HR) and 95% confidence interval (CI) were analyzed to assess the effect.

Results: Eleven eligible studies involving 14,694 participants were included. Metformin increased the OS (HR = 0.87, 95% CI: 0.76–0.99), but failed on DFS (HR = 0.67, 95% CI: 0.40–1.09) or DSS (HR = 0.69, 95% CI: 0.41–1.14) in HNC patients. Subgroup analysis showed metformin was associated with improved OS (HR = 0.66, 95% CI: 0.49–0.88), DFS (HR = 0.49, 95% CI: 0.26–0.92) and DSS (HR = 0.38, 95% CI: 0.22–0.65) in studies with higher Newcastle-Ottawa Scale (NOS) scores. Subgroup analysis of age indicated that patients younger than 65 years (OS, HR = 0.67, 95% CI: 0.49–0.92) were more likely to benefit from metformin treatment. Subgroup analysis of comorbidities showed metformin significantly improved patient outcomes in studies without adjusted for comorbidities (OS, HR = 0.66, 95% CI: 0.51–0.85; DSS, HR = 0.38, 95% CI: 0.22–0.65), but not in studies that adjusted for comorbidities.

Conclusions: Metformin improved the prognosis of HNC patients as an adjuvant therapy, especially in those with higher NOS scores. Age and comorbidities of HNC patients influenced the therapeutic effect of metformin. Further well-conducted investigations are needed.

Metabolic disorders and the risk of head and neck cancer: a protocol for a systematic review and meta-analysis

INTRODUCTION

Head and neck cancer squamous cell carcinoma (HNSCC) is the sixth most common cancer internationally. Established risk factors include smoking, alcohol and presence of human papillomavirus (HPV). The incidence rate of new disease continues to rise, despite falls in alcohol consumption and a reduction in smoking, the rising rates are unlikely to be solely attributed to HPV status alone. Obesity and its associated conditions such as type 2 diabetes (T2D) are implicated in the risk and progression of a variety of cancers, but there is paucity of evidence regarding its role in HNSCC.

METHODS AND ANALYSIS

A systematic review of cohort studies, reporting a risk of incident HNSCC, will be included. A systematic search strategy has been developed, multiple databases will be searched from January 1966 to November 2021, including Cochrane Library, OVID SP versions of Medline and EMBASE. The primary outcome will be incident HNSCC based on exposures of T2D, obesity, dyslipidaemia and hypertension as defined by the WHO. A combined risk effect across studies will be calculated using meta-analysis, although depending on the heterogeneity in study design, exposure and outcome reporting this may not be possible.

ETHICS AND DISSEMINATION

No ethical approval is required for this systematic review. The review will be published in a relevant peer-review journal and findings will be presented at scientific meetings in both poster and oral presentation form.

PROSPERO REGISTRATION NUMBER DETAILS

This study has been registered with the International Prospective Register of Systematic Reviews (PROSPERO) with study registration number CRD42021250520. This protocol has been developed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidance statement.