Hypoxia in head and neck squamous cell carcinoma

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.

Sinonasal Tumors: What the Multidisciplinary Cancer Care Board Wants to Know

Sinonasal neoplasms are a remarkably heterogeneous group, reflecting the numerous tissue types present in the nasal cavity and paranasal sinuses. These entities can be relatively benign (ie, respiratory epithelial adenomatoid hamartoma) or can be exceedingly aggressive (ie, NUT carcinoma). Certain sinonasal tumors have a propensity to spread through local invasion and destruction, while others have a high likelihood of perineural spread. The genetic and molecular mechanisms underlying sinonasal tumor behavior have recently become better understood, and new tumor types have been described using these genetic and molecular data. This has prompted an expansion in the number of tumors included in the World Health Organization fifth edition classification system for head and neck tumors, along with a new classification structure. Radiologists' familiarity with this classification structure is crucial to understanding the expected behavior of these tumors and to collaboration with the multidisciplinary cancer care board in making decisions for optimal patient care. ©RSNA, 2024.

Crosstalk between CAFs and tumour cells in head and neck cancer

Head and neck squamous cell carcinomas (HNSCCs) are amongst the most aggressive, complex, and heterogeneous malignancies. The standard of care treatments for HNC patients include surgery, radiotherapy, chemotherapy, or their combination. However, around 50% do not benefit while suffering severe toxic side effects, costing the individuals and society. Decades have been spent to improve HNSCC treatment outcomes with only limited success. Much of the research in HNSCC treatment has focused on understanding the genetics of the HNSCC malignant cells, but it has become clear that tumour microenvironment (TME) plays an important role in the progression as well as treatment response in HNSCC. Understanding the crosstalk between cancer cells and TME is crucial for inhibiting progression and treatment resistance. Cancer-associated fibroblasts (CAFs), the predominant component of stroma in HNSCC, serve as the primary source of extra-cellular matrix (ECM) and various pro-tumoral composites in TME. The activation of CAFs in HNSCC is primarily driven by cancer cell-secreted molecules, which in turn induce phenotypic changes, elevated secretive status, and altered ECM production profile. Concurrently, CAFs play a pivotal role in modulating the cell cycle, stemness, epithelial-mesenchymal transition (EMT), and resistance to targeted and chemoradiotherapy in HNSCC cells. This modulation occurs through interactions with secreted molecules or direct contact with the ECM or CAF. Co-culture and 3D models of tumour cells and other TME cell types allows to mimic the HNSCC tumour milieu and enable modulating tumour hypoxia and reprograming cancer stem cells (CSC). This review aims to provide an update on the development of HNSCC tumour models comprising CAFs to obtain better understanding of the interaction between CAFs and tumour cells, and for providing preclinical testing platforms of current and combination with emerging therapeutics.

Quantification of oxygen consumption in head and neck cancer using fluorescent sensor foil technology

Introduction

Head and neck squamous cell carcinoma (HNSCC) patients suffer from frequent local recurrences that negatively impact on prognosis. Hence, distinguishing tumor and normal tissue is of clinical importance as it may improve the detection of residual tumor tissue in surgical resection margins and during imaging-based surgery planning. Differences in O2 consumption (OC) can be used to this aim, as they provide options for improved surgical, image-guided approaches.

Methods

In the present study, the potential of a fluorescent sensor foil-based technology to quantify OC in HNSCC was evaluated in an in vitro 3D model and in situ in patients.

Results

In vitro measurements of OC using hypopharyngeal and esophageal cell lines allowed a specific detection of tumor cell spheroids embedded together with cancer-associated fibroblasts in type I collagen extracellular matrix down to a diameter of 440 µm. Pre-surgery in situ measurements were conducted with a handheld recording device and sensor foils with an oxygen permeable membrane and immobilized O2-reactive fluorescent dyes. Lateral tongue carcinoma and carcinoma of the floor of the mouth were chosen for analysis owing to their facilitated accessibility. OC was evaluated over a time span of 60 seconds and was significantly higher in tumor tissue compared to healthy mucosa in the vicinity of the tumor.

Discussion

Hence, OC quantification using fluorescent sensor foil-based technology is a relevant parameter for the differentiation of tumor tissue of the head and neck region and may support surgery planning.

Hypoxia and programmed cell death-ligand 1 expression in the tumor microenvironment: a review of the effects of hypoxia-induced factor-1 on immunotherapy

One useful cancer treatment approach is activating the patient's immune response against the tumor. In this regard, immunotherapy (IT) based on immune checkpoint blockers (ICBs) has made great progress in the last two decades. Although ITs are considered a novel approach to cancer treatment and have had good results in preclinical studies, their clinical success has shown that only a small proportion of treated patients (about 20%) benefited from them. Moreover, in highly progressed tumors, almost no acceptable response could be expected. In this regard finding the key molecules that are the main players of tumor immunosuppression might be helpful in overcoming the possible burdens. Hypoxia is one of the main components of the tumor microenvironment (TME), which can create an immunosuppressive microenvironment in various ways. For example, hypoxia is one of the main factors of programmed cell death ligand-1 (PD-L1) upregulation in tumor-infiltrating Myeloid-Derived Suppressor Cells (MDSCs). Therefore, hypoxia can be targeted to increase the efficiency of Anti-PD-L1 IT and has become one of the important issues in cancer treatment strategy. In this review, we described the effect of hypoxia in the TME, on tumor progression and immune responses and the challenges created by it for IT.

Role of Microenvironmental Components in Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell cancer (HNSCC) is one of the ten most common malignant neoplasms, characterized by an aggressive course, high recurrence rate, poor response to treatment, and low survival rate. This creates the need for a deeper understanding of the mechanisms of the pathogenesis of this cancer. The tumor microenvironment (TME) of HNSCC consists of stromal and immune cells, blood and lymphatic vessels, and extracellular matrix. It is known that HNSCC is characterized by complex relationships between cancer cells and TME components. TME components and their dynamic interactions with cancer cells enhance tumor adaptation to the environment, which provides the highly aggressive potential of HNSCC and resistance to antitumor therapy. Basic research aimed at studying the role of TME components in HNSCC carcinogenesis may serve as a key to the discovery of both new biomarkers-predictors of prognosis and targets for new antitumor drugs. This review article focuses on the role and interaction with cancer of TME components such as newly formed vessels, cancer-associated fibroblasts, and extracellular matrix.

Microneedle-assisted transdermal delivery of perfluorotripropylamine-based oxygenated emulsion gel loaded with 5-aminolevulinic acid for enhanced photodynamic therapy of cutaneous squamous cell carcinoma

Topical photodynamic therapy (TPDT) is a clinical treatment for cutaneous squamous cell carcinoma (CSCC). However, the therapeutic efficacy of TPDT for CSCC is significantly weakened by hypoxia, which is caused by the oxygen-poor environment of the skin and CSCC and by the high oxygen consumption of TPDT itself. To overcome these problems, we developed a topically applied perfluorotripropylamine-based oxygenated emulsion gel loaded with the photosensitizer 5-ALA (5-ALA-PBOEG) by a simple ultrasound-assisted emulsion method. With the aid of the microneedle roller, 5-ALA-PBOEG dramatically increased the accumulation of 5-ALA in the epidermis and the dermis, as well as throughout the dermis; a total of 67.6% ± 9.97% of the applied dose penetrated into and through the dermis, which is 19.1±3.2-fold that of the 5-ALA-PBOEG without microneedle treatment group, and 16.9±0.3-fold that of the aminolevulinic acid hydrochloride topical powder treatment group (p<0.001). Meanwhile, PBOEG enhanced the singlet oxygen yield of 5-ALA-induced protoporphyrin IX. The results of in vivo antitumor activity in human epidermoid carcinoma (A431) bearing mice showed that by increasing the oxygen content in tumor tissues, the developed 5-ALA-PBOEG plus microneedle treatment and laser irradiation showed better tumor growth inhibition than the respective control formulations. In addition, the results of safety studies, including the multiple-dose skin irritation study, allergy tests, and skin H&E staining, demonstrated the safety of 5-ALA-PBOEG plus microneedle treatment. In conclusion, the 5-ALA-PBOEG plus microneedle treatment shows great potential in the fight against CSCC and other skin cancers.

RBM33 is a unique m6A RNA-binding protein that regulates ALKBH5 demethylase activity and substrate selectivity

Regulation of RNA substrate selectivity of m6A demethylase ALKBH5 remains elusive. Here, we identify RNA-binding motif protein 33 (RBM33) as a previously unrecognized m6A-binding protein that plays a critical role in ALKBH5-mediated mRNA m6A demethylation of a subset of mRNA transcripts by forming a complex with ALKBH5. RBM33 recruits ALKBH5 to its m6A-marked substrate and activates ALKBH5 demethylase activity through the removal of its SUMOylation. We further demonstrate that RBM33 is critical for the tumorigenesis of head-neck squamous cell carcinoma (HNSCC). RBM33 promotes autophagy by recruiting ALKBH5 to demethylate and stabilize DDIT4 mRNA, which is responsible for the oncogenic function of RBM33 in HNSCC cells. Altogether, our study uncovers the mechanism of selectively demethylate m6A methylation of a subset of transcripts during tumorigenesis that may explain demethylation selectivity in other cellular processes, and we showed its importance in the maintenance of tumorigenesis of HNSCC.

Overcoming the Impact of Hypoxia in Driving Radiotherapy Resistance in Head and Neck Squamous Cell Carcinoma

Hypoxia is very common in most solid tumours and is a driving force for malignant progression as well as radiotherapy and chemotherapy resistance. Incidences of head and neck squamous cell carcinoma (HNSCC) have increased in the last decade and radiotherapy is a major therapeutic technique utilised in the treatment of the tumours. However, effectiveness of radiotherapy is hindered by resistance mechanisms and most notably by hypoxia, leading to poor patient prognosis of HNSCC patients. The phenomenon of hypoxia-induced radioresistance was identified nearly half a century ago, yet despite this, little progress has been made in overcoming the physical lack of oxygen. Therefore, a more detailed understanding of the molecular mechanisms of hypoxia and the underpinning radiobiological response of tumours to this phenotype is much needed. In this review, we will provide an up-to-date overview of how hypoxia alters molecular and cellular processes contributing to radioresistance, particularly in the context of HNSCC, and what strategies have and could be explored to overcome hypoxia-induced radioresistance.

Targeting Microenvironment of Melanoma and Head and Neck Cancers in Photodynamic Therapy

Background:

Photodynamic therapy (PDT), in comparison to other skin cancers, is still far less effective for melanoma, due to the strong absorbance and the role of melanin in cytoprotection. The tumour microenvironment (TME) has a significant role in tumour progression, and the hypoxic TME is one of the main reasons for melanoma progression to metastasis and its resistance to PDT. Hypoxia is also a feature of solid tumours in the head and neck region that indicates negative prognosis.

Objective:

The aim of this study was to individuate and describe systematically the main strategies in targeting the TME, especially hypoxia, in PDT against melanoma and head and neck cancers (HNC), and assess the current success in their application.

Methods:

PubMed was used for searching, in MEDLINE and other databases, for the most recent publications on PDT against melanoma and HNC in combination with the TME targeting and hypoxia.

Results:

In PDT for melanoma and HNC, it is very important to control hypoxia levels, and amongst the different approaches, oxygen self-supply systems are often applied. Vascular targeting is promising, but to improve it, optimal drug-light interval, and formulation to increase the accumulation of the photosensitiser in the tumour vasculature, have to be established. On the other side, the use of angiogenesis inhibitors, such as those interfering with VEGF signalling, is somewhat less successful than expected and needs to be further investigated.

Conclusion:

The combination of PDT with immunotherapy by using multifunctional nanoparticles continues to develop and seems to be the most promising for achieving a complete and lasting antitumour effect.

Inhibition of carbonic anhydrases IX/XII by SLC-0111 boosts cisplatin effects in hampering head and neck squamous carcinoma cell growth and invasion

Background

Hypoxic tumor microenvironment (TME) contributes to the onset of many aspects of the cancer biology associated to the resistance to conventional therapies. Hypoxia is a common characteristic and negative prognostic factor in the head and neck squamous carcinomas (HNSCC) and is correlated with aggressive and invasive phenotype as well as with failure to chemo- and radio-therapies. The carbonic anhydrase isoenzymes IX and XII (CA IX/XII), regulators of extra and intracellular pH, are overexpressed in TME and are involved in adaptative changes occurring in cancer cells to survive at low O₂. In this study, we aim to investigate in HNSCC cells and murine models the possibility to target CA IX/XII by the specific inhibitor SLC-0111 to potentiate the effects of cisplatin in hampering cell growth, migration and invasion. Furthermore, we analyzed the signal pathways cooperating in acquisition of a more aggressive phenotype including stemness, epithelial-mesenchymal transition and apoptotic markers.

Methods

The effects of cisplatin, CA IX/XII specific inhibitor SLC-0111, and the combinatorial treatment were tested on proliferation, migration, invasion of HNSCC cells grown in 2D and 3D models. Main signal pathways and the expression of stemness, mesenchymal and apoptotic markers were analyzed by western blotting. Molecular imaging using NIR-Annexin V and NIR-Prosense was performed in HNSCC xenografts to detect tumor growth and metastatic spread.

Results

HNSCC cells grown in 2D and 3D models under hypoxic conditions showed increased levels of CA IX/XII and greater resistance to cisplatin than cells grown under normoxic conditions. The addition of CA IX/XII inhibitor SLC-0111 to cisplatin sensitized HNSCC cells to the chemotherapeutic agent and caused a reduction of proliferation, migration and invasiveness. Furthermore, the combination therapy hampered activation of STAT3, AKT, ERK, and EMT program, whereas it induced apoptosis. In HNSCC xenografts the treatment with cisplatin plus SLC-0111 caused an inhibition of tumor growth and an induction of apoptosis as well as a reduction of metastatic spread at a higher extent than single agents.

Conclusion

Our results highlight the ability of SLC-0111 to sensitize HNSCC to cisplatin by hindering hypoxia-induced signaling network that are shared among mechanisms involved in therapy resistance and metastasis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02345-x.

Factors that Influence 2-Year Progression-Free Survival Among Head and Neck Cancer Patients

Objectives

The majority of patients with head and neck cancer (HNC) come to the hospital at advanced stages. This research was conducted to determine the mortality, 2-year progression-free survival (PFS) and factors that influenced PFS of HNC patients.

Methods

A retrospective cohort study was conducted among locally advanced HNC patients who underwent chemoradiation for the first time at RSCM from January 2015 to December 2017. Data were retrieved through medical records. Laboratory data were taken 2–4 weeks prior and 2–4 weeks after chemoradiation. PFS observation started from the first day of chemoradiation until disease progression or death. PFS data were recorded in two groups: ≤ 2 years and > 2 years. The Chi-square test was used for bivariate analysis with the Fischer-exact test as an alternative. Variables will be further tested using multivariate logistic regression tests.

Results

Among 216 subjects, there were 103 (47.69%) patients who did not reach overall survival (OS) > 2 years. There were 108 (50%) patients who had PFS > 2 years. Based on the results of multivariate analysis, it was found that smoking, hemoglobin level ≤ 12 g/dl, ECOG (Eastern Cooperative Oncology Group) 1–2, and negative therapeutic response were associated with poor PFS. Hazard ratio (HR) for 2-year PFS for Brinkman index > 250 was 1.36 (95% CI 0.93–2.00; p = 0.02); HR for Hb ≤ 12 g/dl was 1.65 (95% CI 1.13–2.42; p = 0.01); HR for ECOG 1–2 was 4.05 (95% CI 1.49–11.00; p < 0.01); and HR for negative therapeutic response was 2.37 (95% CI 1.43–3.94; p < 0.01).

Conclusion

Mortality of HNC patients within 2 years is 47.69%, with a 2-year PFS reaching 50%. Cigarette smoking, low hemoglobin levels, poor performance status, and negative therapeutic response (non-responders) negatively affect the 2-year PFS.

Head and neck cancer: Current challenges and future perspectives

Head and neck cancers are a heterogeneous, aggressive and genetically complex collection of malignancies of the oral cavity, nasopharynx, oropharynx, hypopharynx, larynx, paranasal sinuses and salivary glands, which are difficult to treat. About 90% of all head and neck cancers are squamous cell carcinomas (HNSCC). Larynx and Oral cavity carcinomas are generally related with tobacco consumption, alcohol abuse (or both), but pharynx carcinomas are generally associated with infection of human papillomavirus (HPV), especially HPV-16 subtype. Thus, usually HNSCC can be separated into HPV-negative and HPV-positive categories. Despite substantial efforts invested into therapeutic development of HNSCC, the 5-year survival rate of patients with HNSCC still remains dismal. The primary reason being late diagnosis, recurrent metastasis, relapse and resistance to therapies. Currently surgery and radiotherapy represent the baseline treatment options for most initial stage HNSCC patients, but these treatments are associated with significant morbidity and poor prognosis. Moreover, the issue of resistance to both radiotherapy/chemotherapy and recurrent relapse are common in HNSCC. Elucidation of the genetic landscape, tumor microenvironment and aberrant signaling pathways have generated new insights into the molecular pathogenesis of this disease. Thus, the scientific research has therefore been focused on the understanding of HNSCC biology and immunobiology to identification of predictive/prognostic biomarkers, which will be key to develop more effective targeted therapies with less toxicity and high specificity.

Squamous Cell Carcinoma and Lymphoma of the Oropharynx: Differentiation Using a Radiomics Approach

The purpose of this study was to evaluate the diagnostic performance of magnetic resonance (MR) radiomics-based machine learning algorithms in differentiating squamous cell carcinoma (SCC) from lymphoma in the oropharynx. MR images from 87 patients with oropharyngeal SCC (n=68) and lymphoma (n=19) were reviewed retrospectively. Tumors were semi-automatically segmented on contrast-enhanced T1-weighted images registered to T2-weighted images, and radiomic features (n=202) were extracted from contrast-enhanced T1- and T2-weighted images. The radiomics classifier was built using elastic-net regularized generalized linear model analyses with nested five-fold cross-validation. The diagnostic abilities of the radiomics classifier and visual assessment by two head and neck radiologists were evaluated using receiver operating characteristic (ROC) analyses for distinguishing SCC from lymphoma. Nineteen radiomics features were selected at least twice during the five-fold cross-validation. The mean area under the ROC curve (AUC) of the radiomics classifier was 0.750 [95% confidence interval (CI), 0.613-0.887], with a sensitivity of 84.2%, specificity of 60.3%, and an accuracy of 65.5%. Two human readers yielded AUCs of 0.613 (95% CI, 0.467-0.759) and 0.663 (95% CI, 0.531-0.795), respectively. The radiomics-based machine learning model can be useful for differentiating SCC from lymphoma of the oropharynx.

Qualitative expression of hypoxia-inducible factor-1α in malignant transformation of oral submucous fibrosis: An immunohistochemical study

Background

Oral submucous fibrosis (OSF) is a precancerous condition predominantly seen in people of Asian descent. About 7%-12% of OSF patients develop oral squamous cell carcinoma. Morphological features of OSF, especially fibrosis, suggest a possibility of hypoxic environment in diseased tissues. Neovascularization and increased glycolysis, represent adaptations to a hypoxic microenvironment that are correlated with tumor invasion and metastasis. The adaptation of cells to hypoxia appears to be mediated through hypoxia-inducible factor-1α (HIF-1α). HIF-1α is said to be associated with malignant transformation of epithelium in other sites.

Aim

The aim of this study was to investigate the relationship between the expression of HIF-1α in OSMF and its role in malignant transformation.

Materials and Methods

A retrospective study which included 20 histopathologically diagnosed cases of OSF was conducted. A qualitative evaluation of HIF-1α was performed. Statistical analysis was carried out using the IBM Statistical Package for Social Sciences 20.0 version (IBM Corporation, Armonk, NY, USA).

Results

Results showed an increased expression of HIF-1α in OSF.

Conclusion

HIF-1α appears to play a role in malignant transformation of OSF.

Metastatic disease in head & neck oncology

The head and neck district represents one of the most frequent sites of cancer, and the percentage of metastases is very high in both loco-regional and distant areas. Prognosis refers to several factors: a) stage of disease; b) loco-regional relapses; c) distant metastasis. At diagnosis, distant metastases of head and neck cancers are present in about 10% of cases with an additional 20-30% developing metastases during the course of their disease. Diagnosis of distant metastases is associated with unfavorable prognosis, with a median survival of about 10 months. The aim of the present review is to provide an update on distant metastasis in head and neck oncology. Recent achievements in molecular profiling, interaction between neoplastic tissue and the tumor microenvironment, oligometastatic disease concepts, and the role of immunotherapy have all deeply changed the therapeutic approach and disease control. Firstly, we approach topics such as natural history, epidemiology of distant metastases and relevant pathological and radiological aspects. Focus is then placed on the most relevant clinical aspects; particular attention is reserved to tumours with distant metastasis and positive for EBV and HPV, and the oligometastatic concept. A substantial part of the review is dedicated to different therapeutic approaches. We highlight the role of immunotherapy and the potential effects of innovative technologies. Lastly, we present ethical and clinical perspectives related to frailty in oncological patients and emerging difficulties in sustainable socio-economical governance.

Adaptive Changes of Glioblastoma Cells Following Exposure to Hypoxic (1% Oxygen) Tumour Microenvironment

Glioblastoma multiforme is the most aggressive and malignant primary brain tumour, with a median survival rate of between 15 to 17 months. Heterogeneous regions occur in glioblastoma as a result of oxygen gradients which ranges from 0.1% to 10% in vivo. Emerging evidence suggests that tumour hypoxia leads to increased aggressiveness and chemo/radio resistance. Yet, few in vitro studies have been performed in hypoxia. Using three glioblastoma cell-lines (U87, U251, and SNB19), the adaptation of glioblastoma cells in a 1% (hypoxia) and 20% (normoxia) oxygen microenvironment on proliferation, metabolism, migration, neurosphere formation, CD133 and VEGF expression was investigated. Compared to cells maintained in normoxia (20% oxygen), glioblastoma cells adapted to 1% oxygen tension by reducing proliferation and enhancing metabolism. Both migratory tendency and neurosphere formation ability were greatly limited. In addition, hypoxic-mediated gene upregulation (CD133 and VEGF) was reversed when cells were removed from the hypoxic environment. Collectively, our results reveal that hypoxia plays a pivotal role in changing the behaviour of glioblastoma cells. We have also shown that genetic modulation can be reversed, supporting the concept of reversibility. Thus, understanding the degree of oxygen gradient in glioblastoma will be crucial in personalising treatment for glioblastoma patients.

An Immunohistochemical Study of HIF-1 Alpha in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

To evaluate and compare the expression of HIF-1 Alpha (HIF-1α) in oral epithelial dysplasia (OED) and various grades of Oral squamous cell carcinoma (OSCC). 30 cases each of OEDand OSCC were stained with HIF-1α antibody. Quantification of HIF-1α positive cellswas carried out and the data was statistically analysed. The mean % HIF-1α labeling index (HIF-1α LI) increased significantly from mild OED (32.11%), moderate OED (55.07%), to severe OED (64.58%). There was a statistically significant increase in the expression of HIF-1α as grades of OED increased. The mean HIF-1α LI % in well differentiated OSCC was 46.3%, Moderately differentiated OSCC-76.31% and Poorly differentiated OSCC-89.9%. The mean HIF-1α LI was found to increase with increasing grades of OSCC which was statistically significant (P < 0.05). Further a comparison of mean HIF-1α LI in OED with different histologic grades of OSCC by Independent samples t test was performed. We found statistically significant difference between OED and moderately differentiated OSCC and OED and poorly differentiated OSCC (P = 0.000). Progressive increase in expression of HIF-1α was noted from OED to OSCC. It can be postulated that epithelial dysplastic lesions with increased HIF-1α expression are at greater risk of malignant transformation, suggesting that the expression of HIF-1α is an early event in oral carcinogenesis.

A novel approach to target hypoxic cancer cells via combining β-oxidation inhibitor etomoxir with radiation

Background

Hypoxia in tumors is associated with resistance towards various therapies including radiotherapy. In this study, we assessed if hypoxia in cancer spheres could be effectively reduced by adding etomoxir (a β-oxidation inhibitor) immediately after cell irradiation.

Methods

We employed cancer cells’ sphere model to target hypoxia. Confocal imaging was used to analyze hypoxia and expression of specific biomarkers in spheres following various treatments (radiation and/or etomoxir).

Results

Etomoxir (32.5 μM) treatment improved the radiation (2.5 Gy) efficacy against growth of lung adenocarcinoma H460 spheres. More importantly, radiation and etomoxir combination significantly reduced the hypoxic regions (pimonidazole+ areas) in H460 spheres compared to either treatment alone. Also, etomoxir and radiation combination treatment reduced the protein level of biomarkers for proliferation (Ki-67 and cyclin D1), stemness (CD44) and β-oxidation (CPT1A) in H460 spheres. We observed similar efficacy of etomoxir against growth of prostate cancer LNCaP cells’ spheres when combined with radiation. Further, radiation treatment strongly reduced the hypoxic regions (pimonidazole+ areas) in CPT1 knockdown LNCaP cells’ spheres.

Conclusions

Together, these results offer a unique approach to target hypoxia in solid tumors via combining etomoxir with radiation, thereby improving therapeutic efficacy.

Imaging Characteristics of Malignant Sinonasal Tumors

Malignancies of the nasal cavity and paranasal sinuses account for 1% of all malignancies and 3% of malignancies of the upper aerodigestive tract. In the sinonasal tract, nearly half of all malignancies arise in the nasal cavity, whereas most of the remaining malignancies arise in the maxillary or ethmoid sinus. Squamous cell carcinoma is the most common histological subtype of malignant tumors occurring in this area, followed by other epithelial carcinomas, lymphomas, and malignant soft tissue tumors. Although many of these tumors present with nonspecific symptoms, each tumor exhibits characteristic imaging features. Although complex anatomy and various normal variants of the sinonasal tract cause difficulty in identifying the origin and extension of large sinonasal tumors, the invasion of vital structures such as the brain, optic nerves, and internal carotid artery affects patients’ prognosis. Thus, diagnostic imaging plays a key role in predicting the histological subtype and in evaluating a tumor extension into adjacent structures. This article describes the computed tomography and magnetic resonance imaging findings for malignant sinonasal tumors.

Resveratrol Demonstrated Higher Antiproliferative and Antiangiogenic Efficacy Compared with Oxyresveratrol on Head and Neck Squamous Cell Carcinoma Cell Lines

Resveratrol and its derivative, oxyresveratrol, have various pharmacological effects. Several studies demonstrated the anticancer activity of resveratrol. However, little is known about the anticancer activity of oxyresveratrol. In this study, we compared the antiproliferative and antiangiogenic effects of oxyresveratrol and resveratrol. Three head and neck squamous cell carcinoma cell lines (HSC-3, HN-8, and HN-30) were treated with a range of concentrations of either resveratrol or oxyresveratrol. MTT assays demonstrated that resveratrol and oxyresveratrol significantly inhibited cell survival in a dose-dependent manner. Although ELISA and Real-time PCR revealed that oxyresveratrol inhibited vascular endothelial growth factor (VEGF) expression at both the mRNA and protein level, the reduction was lower than that of resveratrol. Altogether, these findings indicate that oxyresveratrol possesses anticancer properties by inhibiting cancer cell proliferation and VEGF expression. However, its efficacy is lower compared with that of resveratrol.

Transcriptomic analyses of the radiation response in head and neck squamous cell carcinoma subclones with different radiation sensitivity: time-course gene expression profiles and gene association networks

BACKGROUND

Acquired and inherent radioresistance of tumor cells is related to tumor relapse and poor prognosis - not only in head and neck squamous cell carcinoma (HNSCC). The underlying molecular mechanisms are largely unknown. Therefore, systemic in-depth analyses are needed to identify key regulators of radioresistance. In the present study, subclones of the CAL-33 HNSCC cell line with different radiosensitivity were analyzed to identify signaling pathways related to the different phenotypes.

METHODS

Subclones with altered radiosensitivity were generated by fractionated irradiation of the parental CAL-33 cells. Differences in radiosensitivity were confirmed in colony formation assays. Selected subclones were characterized at the genomic and transcriptomic level by SKY, array CGH, and mRNA-microarray analyses. Time-course gene expression analyses upon irradiation using a natural cubic spline regression model identified temporally differentially expressed genes. Moreover, early and late responding genes were identified. Gene association networks were reconstructed using partial correlation. The Reactome pathway database was employed to conduct pathway enrichment analyses.

RESULTS

The characterization of two subclones with enhanced radiation resistance (RP) and enhanced radiosensitivity (SP) revealed distinct genomic and transcriptomic changes compared to the parental cells. Differentially expressed genes after irradiation shared by both subclones pointed to important pathways of the early and late radiation response, including senescence, apoptosis, DNA repair, Wnt, PI3K/AKT, and Rho GTPase signaling. The analysis of the most important nodes of the gene association networks revealed pathways specific to the radiation response in different phenotypes of radiosensitivity. Exemplarily, for the RP subclone the senescence-associated secretory phenotype (SASP) together with GPCR ligand binding were considered as crucial. Also, the expression of endogenous retrovirus ERV3-1in response to irradiation has been observed, and the related gene association networks have been identified.

CONCLUSIONS

Our study presents comprehensive gene expression data of CAL-33 subclones with different radiation sensitivity. The resulting networks and pathways associated with the resistant phenotype are of special interest and include the SASP. The radiation-associated expression of ERV3-1 also appears highly attractive for further studies of the molecular mechanisms underlying acquired radioresistance. The identified pathways may represent key players of radioresistance, which could serve as potential targets for molecularly designed, therapeutical intervention.

Differentiation of extranodal non-Hodgkins lymphoma from squamous cell carcinoma of the maxillary sinus: a multimodality imaging approach

This study aimed to assess the efficacy of a multimodality imaging approach for differentiating between primary extranodal non-Hodgkin’s lymphoma (NHL) and squamous cell carcinoma (SCC) of the maxillary sinus. Twelve NHLs and 29 SCCs of the maxillary sinus were included. CT findings, MR signal intensities, apparent diffusion coefficients (ADCs), and maximum standardized uptake values (SUVmax) were correlated with two pathologies. On CT, permeative growth frequency was greater among NHLs than among SCCs (50 % vs. 10 %; p < 0.01), whereas destructive growth frequency was greater among SCCs than among NHLs (83 % vs. 33 %; p < 0.01). On CT, remaining sinus wall within the tumor was more frequent with NHLs than with SCCs (92 % vs. 34 %; p < 0.01), whereas intratumoral necrosis was more frequent with SCCs than with NHLs (86 % vs. 17 %; p < 0.01). ADCs were lower for NHLs than for SCCs (0.61 vs. 0.95 × 10^–3 mm²/s; p < 0.01). No significant differences in MR signal intensities and SUVmax were observed. Tumor growth pattern, remaining sinus wall within the tumor, and intratumoral necrosis were useful CT findings for differentiating between NHLs and SCCs. ADC measurements could assist the differentiation of NHL from SCC.

The domino effect: Role of hypoxia in malignant transformation of oral submucous fibrosis

INTRODUCTION

Oral submucous fibrosis (OSMF) is a precancerous condition predominantly seen in people of Asian descent. About 7-12% OSMF patients develop oral squamous cell carcinoma (OSCC). Morphological features of OSMF especially fibrosis suggests a possibility of the hypoxic environment in diseased tissues. Oral cancer usually develops from hyperplasia through dysplasia to carcinoma. Neovascularization and increased glycolysis, represent adaptations to a hypoxic microenvironment that are correlated with tumor invasion and metastasis. The adaptation of cells to hypoxia appears to be mediated via hypoxia inducible factor-1α (HIF-1α). HIF-1α is said to be associated with malignant transformation of epithelium in other sites. It appears that HIF-1α plays a significant role in both prostate and cervical carcinogenesis at early stages. We hypothesize that progression of OSMF and malignant transformation in the background of fibrosis mediates via HIF-1α either by up- or down-regulation of various such molecules. Therefore, the main objective of this study was to investigate the relationship between the expression of HIF-1α in OSMF, OSCC and OSCC with OSMF.

AIM

To investigate the relationship between the expression of HIF-1α in OSMF, OSCC and OSCC with OSMF.

MATERIALS AND METHODS

The study group consists of histopathologically diagnosed 20 cases of OSCC, oral submucous fibrosis and OSCC with OSMF each. The immunohistochemistry was carried out on neutral buffered formalin-fixed paraffin-embedded tissue sections by using the monoclonal antibody of HIF-1α.

RESULTS

A rise in the expression of HIF-1α from OSMF to OSCC to OSCC with OSMF is observed.

Tumor microenvironment in head and neck squamous cell carcinoma

The tumor microenvironment (TME) of head and neck squamous cell carcinoma (HNSCC) is comprised of cancer-associated fibroblasts (CAFs), immune cells, and other supporting cells. Genetic changes in the carcinoma cells, such as alterations to TP53, NOTCH1, and specific gene expression profiles, contribute to derangements in cancer and microenvironment cells such as increased ROS, overproduction of cytokines, and epithelial to mesenchymal transition (EMT). CAFs are among the most critical elements of the TME contributing to proliferation, invasion, and metastasis. The adaptive immune response is suppressed in HNSCC through overexpression of cytokines, triggered apoptosis of T cells, and alterations in antigen processing machinery. Overexpression of critical cytokines, such as transforming growth factor-β (TGF-β), contributes to EMT, immune suppression, and evolution of CAFs. Inflammation and hypoxia are driving forces in angiogenesis and altered metabolism. HNSCC utilizes glycolytic and oxidative metabolism to fuel tumorigenesis via coupled mechanisms between cancer cell regions and cells of the TME. Increased understanding of the TME in HNSCC illustrates that the long-held notion of "condemned mucosa" reflects a process that extends beyond the epithelial cells to the entire tissue comprised of each of these elements.