Heparanase and cyclooxygenase-2 gene and protein expressions during progression of oral epithelial dysplasia to carcinoma

Association between the variations in metabolic pathways and oral cancer risk: results from a Pakistani case-control study

BACKGROUND

Oral cancer (OC) is a significant global health concern, with Pakistan ranking 5th worldwide in OC incidence. Given the poor prognosis, early detection of at-risk individuals is crucial. Genetic factors, particularly single nucleotide polymorphisms (SNPs) in metabolic genes, may influence OC susceptibility. This study investigated the association between SNPs in CYP1A1, COX2, SOD2, and HIF1a genes and OC risk in the Pakistani population.

METHODS

A prospective study was conducted from October 2019 to March 2022, enrolling 215 newly diagnosed OC patients and 410 controls. Genetic variations were analyzed using High-Resolution Melting (HRM) analysis and Sanger sequencing, with protein expression evaluated by ELISA.

RESULTS

No significant associations were found between the studied SNPs and OC risk. However, a non-significant trend was observed for the SOD2 variant (rs4880), where the G allele was associated with a higher OC risk than the A allele (p = 0.20). Elevated COX2 and HIF1α levels (p-values of 0.014 and < 0.001, respectively) and reduced SOD2 levels (p < 0.0001) were observed in OC patients, while CYP1A1 levels remained similar in both controls and cases.

CONCLUSION

Although SNPs in CYP1A1, COX2, SOD2, and HIF1α were not significantly associated with OC risk in the Pakistani population, altered protein expression levels of COX2, HIF1α and SOD2 suggest additional regulatory mechanisms. Further investigation into post-transcriptional modifications and epigenetic factors could lead to novel biomarkers and therapeutic targets for OC in Pakistan.

Cyclooxygenase-2 (COX-2) expression in oral submucous fibrosis and oral squamous cell carcinoma: An immunohistochemical study

Introduction:

Material and Methods:

Results:

Conclusion:

Histoscore and Discontinuity Score − A Novel Scoring System to Evaluate Immunohistochemical Expression of COX-2 and Type IV Collagen in Oral Potentially Malignant Disorders and Oral Squamous Cell Carcinoma

Introduction:

Cyclooxygenase 2 (COX-2) expression in oral potentially malignant disorders (OPMDs) such as oral submucous fibrosis (OSMF) and oral squamous cell carcinomas (OSCCs) has revealed inconclusive reports. Studies on loss of type IV collagen expression in oral epithelial dysplasias (OEDs) and OSCCs were subjective and lacked systemic approach. To evaluate the immunohistochemical (IHC) expression of COX-2 and type IV collagen in OED, OSMF, and OSCC.

Materials and methods:

IHC expression of COX-2 and type IV collagen on paraffin

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embedded tissue section of 10 cases each in normal oral mucosa, mild OED, moderate OED, and severe OED, OSMF, and OSCC were evaluated using mean H score and discontinuity Score (DS) designed grades for every group, respectively. Mean H score of COX-2 was compared within and between the groups using analysis of variance (ANOVA), and DS designed specifically for type IV collagen expression was compared using Kruskal–Wallis ANOVA. Pairwise comparison between the groups were performed using Tukey multiple posthoc procedure and Mann–Whitney U test for COX-2 and type IV collagen, respectively.

Results:

Mean H scores of COX-2 expression increased significantly (P = 0.0001) as disease progressed from mild OED to severe OED. But COX-2 in OSCC was less than that observed in mild OED (P = 0.0001). Expression of COX-2 in OSMF was more than that observed in moderate OED. Type IV collagen expression decreased as disease progressed from OED to malignancy (P = 0.0001). OSMF indicated a variation in grades of loss of type IV collagen expression.

Conclusion:

Expression of COX-2 in OED, OSMF, and OSCC and DS for type IV collagen expression in our study could be effectively applied to assess the malignant potential of OPMDs. However, further studies need to be implemented on a larger sample size to conclude the above findings.

Role of Cyclooxygenase-2 in Head and Neck Tumorigenesis

The cyclooxygenase-2 (COX-2) is a potent enzyme that converts arachidonic acid to prostaglandins (PG), including PGE2, a key mediator of inflammation and angiogenesis. Importantly, COX-2 is activated in response to inflammatory stimuli, where it is also believed to promote the development and progression of head and neck cancers (HNC). COX-2 can mediate its protumorigenic effect through various mechanisms, such as inducing cell proliferation, inhibition of apoptosis, and suppressing the host’s immune response. Furthermore, COX-2 can induce the production of vascular endothelial growth factors, hence, promoting angiogenesis. Indeed, the ability of COX-2 inhibitors to selectively restrict the proliferation of tumor cells and mediating apoptosis provides promising therapeutic targets for cancer patients. Thus, in this comprehensive review, we summarized the reported differential expression patterns of COX-2 in different stages of head and neck carcinogenesis—from potentially premalignant lesions to invasive carcinomas. Furthermore, we examined the available meta-analysis evidence for COX-2 role in the carcinogenesis of HNC. Finally, further understanding of the biological processes of COX-2 and its role in orchestrating cell proliferation, apoptosis, and angiogenesis may give therapeutically beneficial insight to develop the management plan of HNC patients and improve their clinical outcomes.

Diclofenac sodium gel therapy as an alternative to actinic cheilitis

OBJECTIVE

Actinic cheilitis (AC) is a potentially malignant lesion caused by prolonged exposure to ultraviolet light. The aim of this research was to analyze the efficacy of diclofenac sodium 3% gel in the treatment of this condition, through clinical follow-up.

METHODS

Thirty-one patients diagnosed with AC were instructed to perform a topical application of the gel three times a day for a period of 90 days. In each visit, a digital photography was obtained for verified progress and response to treatment. Two researchers evaluated all images after treatment was completed and assigned the following scores regarding clinical aspect of the lip: 1, complete improvement; 2, partial improvement; 3, no changes; 4, worsening of the clinical condition. In addition, the patients' tolerability to the drug and their satisfaction after treatment were evaluated.

RESULTS

Twelve cases abandoned the treatment for reasons unrelated to the study. Ten participants showed total remission of all clinical features of the lesion and three had partial improvement of the characteristics. One participant presented worsening of clinical condition, and in five cases, treatment was discontinued due to development of mild adverse effects at the site of gel application. Regarding satisfaction analyses and tolerability to the drug, from 14 patients who completed treatment without adverse effects or complications, most agreed fully that they were satisfied with the therapy (n = 11) and that the drug was not irritating to the mouth (n = 9). Patients are being monitored without clinical signs of recurrence and/or progression of the lesions.

CONCLUSION

Topical application of the drug has provided a convenient and well tolerated in most cases.

CLINICAL RELEVANCE

Diclofenac sodium gel (3%) may be a promising alternative for treatment of actinic cheilitis.

Cyclooxygenase-2--An Imperative Prognostic Biomarker in Oral Squamous Cell Carcinoma--An Immunohistochemical Study

Oral squamous cell carcinoma (OSCC) is the most common head and neck squamous cell carcinoma (HNSCC) with metastasis and tumor recurrence resulting in 90 % of cancer associated mortality. COX-2, an inflammatory biomarker, has been shown to play a significant role in tumorigenesis of OSCC. To study the expression of COX-2 in OSCC by immunohistochemistry and investigate its association with the clinicopathological parameters including patient survival. A cross sectional study was carried out in 75 histologically confirmed cases of OSCC. COX-2 expression was evaluated by indirect streptavidin biotin method. The expression was semi-quantitatively assessed using established criteria. The expression profile of COX-2 was correlated with the clinicopathological details like tumor size, regional lymphnode metastasis, distant metastasis, clinical stage, local recurrence of tumor, histological grade, and survival of patient. Chi square and Kaplan Meier statistical tests were applied for assessing this association. COX-2 expression was absent in normal oral mucosa. Over expression of COX-2 was seen in 58 out of 75 specimens of OSCC. Overexpression of COX-2 was significantly associated with the lymphnode involvement, histological grade, local recurrence of tumor and patient survival. COX-2 expression represents an important biomarker of prognostic significance that may be used to identify a subset of patients at high risk and to predict patient survival.

Development of a complete human anti-human transferrin receptor C antibody as a novel marker of oral dysplasia and oral cancer

Oral squamous cell carcinoma (OSCC) is the sixth most common cancer worldwide. Up to 20% of oral dysplasia cases have been suggested to undergo malignant transformation to OSCC; however, there are no methods to predict OSCC development. In this study, to identify the genes associated with oral dysplasia progression, we performed genomic copy number analyses of genomic DNA samples isolated from primary oral dysplasia and OSCC via the microdissection method and found elevated expression of transferrin receptor C (TfR1/TFRC) with genomic amplification in oral dysplasia and OSCC. The expression rate of TFRC in OSCC was significantly higher than that in dysplasia, suggesting that OSCC disease progression might be related to TFRC expression. Additionally, we investigated the in vitro and in vivo impacts of a newly established anti-human TFRC monoclonal antibody, which was isolated from a human cDNA library using the phage-display method, on cell proliferation and survival. The anti-TFRC antibody blocked the interaction between transferrin and TFRC and consequently inhibited iron uptake, leading to the iron deprivation-mediated suppression of cell growth and induction of apoptosis. Moreover, we demonstrated that the anti-TFRC antibody efficiently inhibited tumor growth in a murine xenograft OSCC model. Therefore, we suggest our developed complete human anti-human TFRC antibody as a useful, novel treatment for oral dysplasia and OSCC.

Induction of heparanase by HPV E6 oncogene in head and neck squamous cell carcinoma

High-risk human papillomavirus (HPV)-positive head and neck squamous cell carcinomas (HNSCCs) are highly invasive; however the identity of downstream effectors responsible for their aggressive phenotype remains underinvestigated. Here, we report that HPV-mediated up-regulation of heparanase enzyme can provide mechanistic explanation for augmented invasiveness of HPV-positive HNSCCs. Heparanase is the sole mammalian enzyme (endo-β-d-glucuronidase) degrading heparan sulphate glycosaminoglycan, key polysaccharide of the extracellular matrix. Cleavage of heparan sulphate by heparanase leads to disassembly of extracellular barriers, enabling local invasion and metastatic spread of the tumour, and releases heparan sulphate-bound growth factors from the extracellular depots. Heparanase is tightly implicated in head and neck cancer progression; yet, molecular mechanisms underlying transcriptional activation of the heparanase gene in HNSCC are largely unknown. We found that HPV16 oncogene E6 is capable of inducing overexpression of heparanase in HNSCC. Notably, radiation treatment dose-dependently suppresses E6-induced heparanase expression in vitro. Our results provide the first evidence for a functional involvement of HPV in heparanase induction in head and neck tumourigenesis and, given ongoing clinical testing of several heparanase-inhibiting compounds, offer important avenue for future therapeutic exploration in HNSCC, as well as other HPV-associated malignancies (i.e. cervical carcinoma).