Older adults, appendicular anthropometric measurements, and poor functional performance are predictors of sarcopenia in individuals with head and neck squamous cell carcinoma.

OBJECTIVE: To identify predictors of sarcopenia (demographical, anthropometric measurements, tumor-related clinical characteristics, performance status, and serum C-reactive protein (CRP) and albumin levels in individuals with head and neck squamous cell carcinoma (HNSCC). MATERIAL AND METHODS: This cross-sectional study selected diagnosed with HNSCC (n = 125). Sarcopenia was defined as low muscle strength and low physical performance. Association between sarcopenia and anthropometric assessments (weight, height, body mass index, triceps skinfold, mid-upper arm circumference [MUAC], mid-upper arm muscle circumference, mid-upper arm fat area [UFA], mid-upper arm bone free muscle area, calf circumference, and appendicular skeletal muscle mass and index), tumor clinical characteristics (anatomical site, tumor size, and cervical metastasis), performance status scale (Eastern Cooperative Oncology Group Performance Status [ECOG-PS]), and CRP and albumin levels was analyzed using binary logistic regression models. RESULTS: The diagnosis of sarcopenia was identified in 28 (22.4%) individuals with HNSCC. Being an older adult increases the odds of association with sarcopenia in individuals with HNSCC (odds ratio [OR] = 1.05). Increments in MUAC measurement reduce the odds of association with sarcopenia (OR = 0.69), while the increase in the UFA measurement increases the odds of association with sarcopenia (OR = 1.33). Poor ECOG-PS scores increase the odds of association with sarcopenia in individuals with HNSCC (OR = 5.54). CONCLUSION: Early identification of easy-to-perform, cost-effective predictors of sarcopenia tends to favor the implementation of personalized therapeutic and supportive interventions in individuals with HNSCC.

Identification of potential biomarkers and survival analysis for oral squamous cell carcinoma: A transcriptomic study.

OBJECTIVE: Oral squamous cell carcinoma (OSCC) is one of the most common neoplasms worldwide. The current study aimed to identify potential biomarkers associated with OSCC survival. MATERIALS AND METHODS: Differentially expressed genes (DEGs) in atypical OSCC cases were identified using two public datasets: The Cancer Genome Atlas and the Gene Expression Omnibus database. Receiver operating characteristic (ROC) analysis was performed to identify the cutoff, and the candidate DEGs related to survival. Kaplan-Meier and Cox regression analysis using the categorized genes were employed to identify genes that impact the overall survival in OSCC. RESULTS: A total of 263 OSCC samples and 105 healthy tissues were used to identify 295 upregulated and 131 downregulated genes expressed only in non-smokers. ROC analyses identified 25 candidate genes associated with death. Survival analyses demonstrated that the following DEGs, namely CSTA, FGFR2, MMP19, OLR1, PCSK1, RAMP2, and CGB5, are potential OSCC prognostic factors. CONCLUSION: We found that CSTA, FGFR2, MMP19, OLR1, PCSK1, RAMP2, and CGB5 are associated with a low survival rate in OSCC. However, further studies are needed to validate our findings and facilitate the development of these factors as potential biomarkers for OSCC survival.

Photodynamic therapy mediated by nanoparticles Aluminum Chloro Phthalocyanine in oral squamous carcinoma cells.

The aim of this study is to investigate the antineoplastic potential of photodynamic therapy (PDT) mediated by an aluminum-phthalocyanine chloride nanoemulsion (AlPc-NE), against an oral squamous cell carcinoma (OSCC) cell line in vitro. Both OSCC (SCC9) and A431 cell lines were studied in vitro. Four study groups were used: Group 1 (phosphate-buffered saline [PBS]), Group 2 (PBS + 28.3 J/cm2 irradiation), Group 3 (AlPc-NE alone), and Group 4 (AlPc-NE + 28.3 J/cm2 irradiation). To test the effect of PDT with AlPc-NE, cell viability, migration, and cell death assays were performed. Moreover, the expressions of Ki-67 and TP53 were evaluated using immunoassays. The results showed that PDT mediated by all AlPc-NE concentrations evaluated (i.e., 0.7, 0.35, and 0.17 nM AlPc) significantly reduced the viability of SCC9 cells. Migration and cell death assays also revealed that PDT with AlPc-NE significantly reduced the rate of migration and increased cell death compared to the control groups. In addition, it was found that PDT with AlPc-NE reduced Ki-67 and mutated TP53 immunoexpression. PDT with AlPc-NE is effective in reducing the viability and migration of SCC9. Moreover, PDT with AlPc-NE nanoemulsions reduces the cell proliferation and expression of mutant TP53.

Effect of low-level light therapy before radiotherapy in oral squamous cell carcinoma: An in vitro study.

Radiation therapy for head and neck squamous cell carcinoma (HNSCC) is associated with several complications. Although photobiomodulation (PBM) has radioprotective effects in normal tissue, it could also enhance the growth of neoplastic cells. Thus, the present study aimed to investigate the cellular response of oral squamous cell carcinoma with pre-exposure to low-level phototherapy before radiotherapy. SCC9, Cal-27, A431, and HaCaT cell lines were subjected to low-level light therapy and radiotherapy. The cells were treated with a single energy density (300 J/cm2) of a light-emitting diode (660 nm) prior to ionizing radiation at different doses (0, 2, 4, and 6 Gy). After 24 h, wound scratch, proliferation, clonogenic cell survival, cell death, and reactive oxygen species (ROS) analyses were performed to evaluate cell response. The cell lines pre-exposed to PBM at the analyzed dosage were radiosensitive. The treatment significantly reduced cell proliferation and clonogenic cell survival. Migration and cell death assays also revealed positive results, with the treatment group showing lower rate of migration and higher cell death than did the control group. Moreover, PBM effectively increased the intracellular levels of ROS. PBM at 300 J/cm2 is a promising radiosensitizing modality to reduce the radiation dose and avoid the intolerable side effects of radiotherapy for HNSCC, thus increasing the probability of successful treatment. However, further studies are needed to support and confirm the results.

Enalapril improves obesity associated liver injury ameliorating systemic metabolic markers by modulating Angiotensin Converting Enzymes ACE/ACE2 expression in high-fat feed mice.

Obesity is a chronic disease caused multiple associated factors that results in excessive body fat accumulation. The Renin-Angiotensin System (RAS) unbalance is now recognized as a key factor on regulating body energy and metabolism. AIM: The aim of the present study was to evaluate the Enalapril (ACE inhibitor) effects on the metabolic function and hepatic steatosis of obese mice evaluating Angiotensin Converting Enzymes (ACEs) expression. METHODS: The experiment was performed using 32 male Swiss mice (8 weeks old) equally and randomly divided into 4 groups (n = 8): standard diet (ST), standard diet plus Enalapril (ST + ENAL), hyperlipidic diet (HF) and hyperlipidic diet plus Enalapril (HF + ENAL). Weekly measurements of animal weight and feed consumption were performed. At the end of treatment period a glucose tolerance test (GTT) and insulin sensitivity test (IST) were performed. Ultrasonography was used to evaluate hepatic and epididymal fat pad. Liver samples were submitted to HE histology and gene expression analyses were performed using Real-Time PCR. RESULTS: The main results showed a decrease in body weight after treatment with Enalapril, as well as a reduced size of epididymal fat pad (EFP). Hepatic echogenicity and steatosis measurement were lower in the obese groups treated with Enalapril also modulating ACE2/ACE expressions. CONCLUSIONS: Enalapril use improved metabolism reducing hepatic steatosis, decreasing ACE expression and increasing ACE2 expression.

Prion protein is associated with a worse prognosis of head and neck squamous cell carcinoma.

BACKGROUND: Head and neck squamous cell carcinoma (HNSC) etiopathogenesis remains unclear, and the biological changes with the activation of heat shock proteins (HSPs) and prion protein (PRNP) promoted by hypoxia in HNSC are undetermined. This study investigates hypoxia's effect in lymph node metastasis by PRNP expression changes and its main partners. METHODS: The study combined a theoretical/cell culture study with a case-control study. First, bioinformatics and cell culture were performed. A case-control study was performed in a second step by comparing HNSC patients with and without lymph node metastasis. ANALYSES: The Cancer Genome Atlas (TCGA) data source validates the theory in the global population study. RESULTS: Bioinformatics analysis suggests that hypoxia-inducible factor-1α (HIF1A) is associated with HSPA4, HSP90AA1 and PRNP expression. TCGA data validate the hypothesis that higher HSP90AA1, HSPA4 and PRNP are related to metastases and low survival. Herein, the cell study demonstrated that muted PRNP did not respond to hypoxia. DISCUSSION: Our results collectively provide the first evidence that PRNP promotes HNSC lymph node metastasis progression through the upregulation of HSPA4, HSP90AA1 and HIF1A. Our findings may provide a molecular basis for the promoting Role of PRNP in HNSC progression.

High levels of ANXA2 are characteristic of malignant salivary gland tumors.

OBJECTIVE: Malignant salivary gland tumors (MSGTs) present different phenotypic characteristics and various clinical outcomes, which proved to be a diagnostic challenge. Considering the heterogeneity of MSGT, this study aims to identify molecule related to the nature of MSGT. METHODS: For screening, proteomic analysis comparing MSGT with pleomorphic adenoma (PA) and salivary gland was performed. The MSGT-associated protein which presented in the higher number in the Gene Expression Omnibus (GEO) database was selected. To validate the data, immunohistochemistry (IHC) was performed in 14 patients with PA, 22 patients with MSGT, and 14 controls. RESULTS: 16 proteins were associated with MSGT. ANXA2 was the primary protein, according to GEO database analyses. ANXA2 was most expressed in the cell membrane. However, some ANXA2 staining was also observed in the cytoplasm and nucleus. ANXA2 was highly expressed in MSGT in comparison with control. Also, ANXA2 has a higher expression in adenocarcinoma not otherwise specified (ANOS) and myoepithelial carcinoma (MC) in comparison with PA. CONCLUSION: In conclusion, this study demonstrated that MSGT presented higher levels of ANXA2 in comparison with normal salivary glands. Also, ANXA2 might be interesting as a molecular marker of ANOS and MS.

Leptin impairs the therapeutic effect of ionizing radiation in oral squamous cell carcinoma cells.

PURPOSE: Leptin, an important hormone controlling energy homeostasis, has been linked to the pathogenesis of oral squamous cell carcinoma (OSCC). Evidence indicates that head and neck cancer patients undergoing radiotherapy show decreased leptin levels after radiotherapy treatment. Thus, we investigated, through phenotypic and molecular analyses, whether leptin can compromise the therapeutic effect of ionizing radiation and neoplastic behavior of OSCC cells. METHODS: The human OSCC-derived cell lines SCC9 and SCC4 were treated with human recombinant leptin and exposed to 6 Gy of irradiation. We performed the in vitro assays of cell migration, death, proliferation, and colony-forming ability. The reactive oxygen species (ROS) levels and proteome analysis by mass spectrometry were also conducted. RESULTS: Leptin was able to increase cell proliferation, migration, and colony-forming ability, despite the suppressive effect induced by irradiation. Furthermore, the leptin promoted a significant reduction of ROS intracellular accumulation, and increased expression of the cancer-related proteins, as ACTC1, KRT6A, and EEF2 in irradiated OSCC cells. CONCLUSIONS: Our findings suggest that leptin impairs responsivity of OSCC cells to the ionizing radiation, reducing the suppressive effects of irradiation on the neoplastic phenotype, and increasing protein expression critical to carcinogenesis.

Treatment of mucositis with combined 660- and 808-nm-wavelength low-level laser therapy reduced mucositis grade, pain, and use of analgesics: a parallel, single-blind, two-arm controlled study.

Oral squamous cell carcinoma (OSCC) is the most frequent oral malignant neoplasia. As consequence of OSCC treatment, oral mucositis (OM) is one of the most common adverse effects of OSCC treatment. Currently, there is no consensus for OM treatment. The purpose of the current study was to test the combination of red and infrared low-level laser therapy (LLLT) for OM treatment. Primary culture of human fibroblast was performed to identify LLLT dose. After laboratory tests, a two-arm parallel, single-blind, controlled study was conducted. The two arms were group 1, both 660- and 808-nm wavelengths (300 J/cm2, 9 J of total energy, 100 mW, spot size 3 mm2), and group 2, only 660-nm wavelength (300 J/cm2, 9 J of total energy, 100 mW, spot size 3 mm2). Both treatments were performed twice a week. Group 1 presented a reduction of mucositis grade in comparison to group 2. Group 1 also presented reduction of analgesics prescription. But no significant differences between groups 1 and 2 were observed according to the pain scale. In conclusion, the current study demonstrated that a combination of red and infrared at a higher dose (300 J/cm2) reduced both oral mucositis grade and analgesics prescription. The effects of the combination of RT and LLLT are unclear and need more studies.

Leptin acts on neoplastic behavior and expression levels of genes related to hypoxia, angiogenesis, and invasiveness in oral squamous cell carcinoma.

Leptin, one of the main hormones controlling energy homeostasis, has been associated with different cancer types. In oral cancer, its effect is not well understood. We investigated, through in vitro and in vivo assays, whether leptin can affect the neoplastic behavior of oral squamous cell carcinoma. Expression of genes possibly linked to the leptin pathway was assessed in leptin-treated oral squamous cell carcinoma cells and also in tissue samples of oral squamous cell carcinoma and oral mucosa, including leptin, leptin receptor, hypoxia-inducible factor 1-alpha, E-cadherin, matrix metalloproteinase-2, matrix metalloproteinase-9, Col1A1, Ki67, and mir-210. Leptin treatment favored higher rates of cell proliferation and migration, and reduced apoptosis. Accordingly, leptin-treated oral squamous cell carcinoma cells show decreased messenger RNA caspase-3 expression, and increased levels of E-cadherin, Col1A1, matrix metalloproteinase-2, matrix metalloproteinase-9, and mir-210. In tissue samples, hypoxia-inducible factor 1-alpha messenger RNA and protein expression of leptin and leptin receptor were high in oral squamous cell carcinoma cases. Serum leptin levels were increased in first clinical stages of the disease. In animal model, oral squamous cell carcinoma-induced mice show higher leptin receptor expression, and serum leptin level was increased in dysplasia group. Our findings suggest that leptin seems to exert an effect on oral squamous cell carcinoma cells behavior and also on molecular markers related to cell proliferation, migration, and tumor angiogenesis.

Molecular finds of pressure ulcer: A bioinformatics approach in pressure ulcer.

BACKGROUND: Understanding the biological processes underlying Pressure Ulcer (PU) is an important strategy to identify new molecular targets. Bioinformatics has emerged as an important screening tool for a broad range of diseases. OBJECTIVE: This study aim of the current study is to investigate the protein-protein interaction in the PU context by bioinformatics. METHODS: We performed a search in gene databases, and bioinformatics algorithms were used to generate molecular targets for PU based in silico investigation. Interactions networks between protein-coding genes were built and compared to skin. RESULTS: TNFA, MMP9, and IL10 genes have higher disease-related connectivity than a connectivity general global. MAGOH, UBC, and PTCH1 as were leader genes related to skin. Ontological analysis demonstrated different mechanisms associated, such as response to oxidase stress. CONCLUSION: TNFA, MMP9, and IL10 are possible therapeutic targets for pressure ulcer. Additional investigation of cell post-transcriptional machinery should be investigated in PU.

Fuzzy clustering demonstrates that codon 72 SNP rs1042522 of TP53 gene associated with HNSCC but not with prognoses.

It is estimated that 7.6 million people will die as a consequence of head and neck squamous cell carcinoma (HNSCC). Genetic predisposition has emerged as an important risk factor in the development and prognosis of HNSCC. Considering this, the aim of the current study is to assess whether codon 72 SNP of the TP53 gene (rs1042522) is associated with an increased odds ratio of developing HNSCC or with a worse prognosis in patients with HNSCC. Analysis of the rs1042522 in HNSCC patients and in control individuals. Differences between the case and control groups were determined using chi-squared tests. Multivariate analysis was performed to evaluate the odds ratio of HNSCC. Fussy C Means Clustering was to cluster HNSCC patients for survival analyses. Time of survival was calculated using the Kaplan-Meier estimator and comparing this to the log rank test. Statistical significance was set at p < 0.05. A total of 71.4 % of the Arg/Arg genotype were from HNSCC patients, while only 28.6 % of Arg/Arg genotype were found in the control group. Logistic regression demonstrated that the Arg/Arg genotype, smoking, and alcohol consumption increase the odds ratio of HNSCC. No association between TP53 codon 72 polymorphism and P53 expression. No association between rs1042522 and survival or prognoses was observed. This study identified that individuals carrying the arginine allele at rs1042522 have an increased odds ratio of HNSCC. However, no association between codon 72 SNP of the TP53 gene and HNSCC prognosis or P53 expression was observed.

p16 (CDKN2A) SNP rs11515 was not associated with head and neck carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is considered a serious public health problem in many countries. Recently, genetic variations have been considered as important factors to cancer susceptibility and prognosis. More specifically, genetic polymorphisms have been associated with the development and prognosis of HNSCC. The purpose of the current study was to investigate an association among p16 (CDKN2A) gene polymorphism at rs11515, age, and HNSCC aggressiveness. PCR-RFLP analysis was used to investigate the p16 (CDKN2A) gene in 96 patients with HNSCC and in 100 individuals without HNSCC. A case group was categorized by age in younger (<60 years) and older (≥ 60 years) patients. Differences between the case and control groups were determined using Fisher and chi-squared tests. Time of survival was calculated from the date of diagnosis to the date of last follow-up visit or to the date of death using the Kaplan-Meier estimator and comparing this to the log-rank test. Statistical significance was set at p<0.05. In the present study, no association was established between HNSCC and rs11515 polymorphism, as indicated in a previous study. We found that HNSCC individuals with large-sized tumors and with metastatic disease presented worse overall survival, consistent with fundamental concepts that establish the effects of tumor size and lymph node metastasis to HNSCC outcomes. This study identified that there is no difference in the distribution of rs11515 between the control and HNSCC groups. In addition, no differences between rs11515 genotypes and clinicopathological parameters were observed.

Dietary supplementation with black cricket (Gryllus assimilis) reverses protein-energy malnutrition and modulates renin-angiotensin system expression in adipose tissue.

Edible insects are recognized as promising food sources due to their nutritional composition. Some species, such as Gryllus assimilis, contain proteins, lipids, and carbohydrates of high biological value, which regulate several metabolic functions, including the Renin-Angiotensin System (RAS). In this context, the present study aimed to assess the effects of dietary supplementation with whole Gryllus assimilis powder on the metabolism of malnourished mice. Thirty-two male Swiss mice were used and divided into four treatment groups. The groups were identified as (AIN93-M); AIN93-M + Gryllus assimilis diet (AIN93-M + GA); AIN93-M + Renutrition diet (AIN93-M + REN) and AIN93-M + Renutrition diet + Gryllus assimilis (AIN93-M + REN + GA). The results showed that whole Gryllus assimilis powder inclusion promotes recovery from protein-energy malnutrition, reduces adiposity, and improves glucose tolerance and insulin sensitivity. It also reduces total cholesterol, triglycerides, VLDL, and adipocyte area. We also observed a significant increase in the expression of RAS-related genes, such as ACE2 and MasR, followed by a reduction in Angiotensinogen and ACE. The main findings of the present study suggest the use of black cricket as a viable strategy for the prevention and treatment of protein-energy malnutrition, as well as the reduction of adiposity, and improvement of lipid and glycemic parameters, with antihypertensive potential.

Effects of gallic acid and physical training on liver damage, force, and anxiety in obese mice: Hepatic modulation of Sestrin 2 (SESN2) and PGC-α expression.

Obesity and overweight are multifactorial diseases affecting more than one-third of the world's population. Physical inactivity contributes to a positive energy balance and the onset of obesity. Exercise combined with a balanced diet is an effective non-pharmacological strategy to improve obesity-related disorders. Gallic acid (GA), is a natural endogenous polyphenol found in a variety of fruits, vegetables, and wines, with beneficial effects on energetic homeostasis. The present study aims to investigate the effects of exercise training on obese mice supplemented with GA. Animal experimentation was performed with male Swiss mice divided into five groups: ST (standard control), HFD (obese control), HFD + GA (GA supplement), HFD + Trained (training), and HFD + GA + Trained (GA and training). The groups are treated for eight weeks with 200 mg/kg/body weight of the feed compound and, if applicable, physical training. The main findings of the present study show that GA supplementation improves liver fat, body weight, adiposity, and plasma insulin levels. In addition, animals treated with the GA and a physical training program demonstrate reduced levels of anxiety. Gene expression analyses show that Sesn2 is activated via PGC-1α independent of the GATOR2 protein, which is activated by GA in the context of physical activity. These data are corroborated by molecular docking analysis, demonstrating the interaction of GA with GATOR2. The present study contributes to understanding the metabolic effects of GA and physical training and demonstrates a new hepatic mechanism of action via Sestrin 2 and PGC-1α.

Comparative study of dietary fat: lard and sugar as a better obesity and metabolic syndrome mice model.

BACKGROUND: Diet macronutrient heterogeneity hinders animal studies' data extrapolation from metabolic disorders to human diseases. OBJECTIVE: The present study aimed to evaluate different fat-diet compositions' effect on inducing lipid/glucose metabolism alterations in mice. METHODS: Swiss male mice were fed for 12 weeks with five different diets: Standard Diet (ST), American Institute of Nutrition 93 for growth (AIN93G) high-butter/high-sugar (HBHS), high-lard/high-sugar (HLHS), and high-oil/high-sugar diet (soybean oil) (HOHS). Several parameters, such as serum biochemistry, histology, and liver mRNA expression, were accessed. RESULTS: The main findings revealed that the HLHS diet dramatically altered liver metabolism inducing hepatic steatosis and increased total cholesterol, triglycerides, VLDL, increasing liver CCAAT/enhancer binding protein (CEBP-α), Acetyl-CoA carboxylase (ACC) and Catalase (CAT) mRNA expression. Moreover, the HLHS diet increased glucose intolerance and reduced insulin sensitivity. CONCLUSIONS: High-fat/high-sugar diets are efficient to induce obesity and metabolic syndrome-associated alterations, and diets enriched with lard and sugar showed more effective results.

The antineoplastic potential of crotoxin isolated from Crotalus durissus terrificus snake venom on oral squamous cell carcinoma.

This study investigated the antineoplastic effects of crotoxin isolated from snake venom of the South American Crotalus durissus terrificus in oral cancer cell lines and in an animal model of chemically induced oral cancer. We analyzed cell viability and death, clonogenic formation, DNA fragmentation, migration assay, and gene expression of MMP2, MMP9, COL1A1, and CASP3. In the animal model, after induction of oral cancer by 4-nitroquinoline-1-oxide carcinogen, mice were treated with crotoxin to investigate its effects on tumor development in tongue and oral mucosa. Crotoxin inhibited cell proliferation, viability, colony formation, and migration, favoring cell death. Furthermore, crotoxin increased caspase-3 expression, decreased Ki-67 protein and mRNA expression of MMP2, MMP9, and COL1A1. Mice treated with crotoxin at 10 µg/kg did not alter biochemical parameters total cholesterol, very-low-density lipoprotein, high-density lipoprotein, liver transaminases, glycemia, creatinine, and urea. Crotoxin treatment significantly reduced the frequency of oral squamous cell carcinoma lesions by 50%. Thus, this study highlights crotoxin as a promising chemotherapeutic substance, considering its effects on controlling the neoplastic cell population, reducing cell migration, and inhibiting tumor development. Clinical studies are necessary to understand better the impact of crotoxin as a potential adjuvant therapeutic agent for oral cancer patients.

Gallic acid has an inhibitory effect on skin squamous cell carcinoma and acts on the heat shock protein HSP90AB1.

Differences in the features of aggressiveness of non-melanoma skin cancer (NMSC) subtypes, between basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are relevant characteristics. Comparing the characteristics between NMSC subtypes might help identify molecules associated with cancer metastasis and invasion. Considering these facts, the current study aimed to identify a molecular target for inhibiting skin cancer metastasis and invasion. Proteomic analysis suggested that heat shock protein 90 kDa, alpha, class B member 1 (HSP90AB1), pentaxin (PTX3), caspase-14 (CASP14), S100, actin-1, and profilin were the primary targets related to metastasis and invasion. However, after a differential expression comparison between BCC and SCC, HSP90AB1 was identified as the best target to repress metastasis and invasion. Based on molecular docking results, gallic acid (GA) was selected to inhibit HSP90AB1. A specific Hsp90ab1 siRNA targeting was designed and compared to GA. Interestingly, GA was more efficient in silencing HSP90AB1 than siRNAhsp90ab1. Hence, our data suggest that HSP90AB1 is a crucial biomarker for identifying invasion and metastasis and that its inhibition may be a viable strategy for treating skin cancer.

Analysis of p16(CDKN2A) methylation and HPV-16 infection in oral mucosal dysplasia.

OBJECTIVE: The purpose of this study was to investigate the relationship between p16(CDKN2A) methylation and epithelial dysplasia (ED). We also evaluated the expressions of proteins related to methylation (DNMT3B and DNMT1). Finally, we tested whether HPV-16/18 or the dmt3b (C46359T) polymorphism is associated with p16(CDKN2A) methylation status. METHODS: To test the hypothesis, a case-control study with 72 (control, n = 24; ED, n = 48) tissue samples from subjects was performed. Methylation-specific PCR, RFLP, and immunohistochemical analyses were performed to evaluate p16(CDKN2A) methylation status, dmt3b (C46359T) genotyping, and protein levels, respectively. RESULTS: The methylation of p16(CDKN2A) and HPV-16 was associated with ED gradation (p = 0.001 and 0.002, respectively). In addition, most HPV-16-positive samples (77.8%) exhibited p16(CDKN2A) methylation; however, changes in DNMT3B and DNMT1 protein levels were not observed in HPV-positive samples. Neither HPV-18 nor the dmt3b polymorphism was associated with p16(CDKN2A) methylation. CONCLUSIONS: There is an association between the presence of HPV-16 in ED and the occurrence of p16(CDKN2A) methylation. Both variables are also associated with ED development, but further studies are necessary to clarify if they operate independently and if they have any impact on OD malignization.