Cholesterol depletion induces mesenchymal properties in oral squamous cell carcinoma cell line.

BACKGROUND: Cholesterol in cell membranes is crucial for cell signaling, adhesion, and migration. Membranes feature cholesterol-rich caveolae with caveolin proteins, playing roles in epithelial-mesenchymal transition and cancer progression. Despite elevated cholesterol levels in tumors, its precise function and the effects of its depletion in oral squamous cell carcinoma remain unclear. The aim of this study was to evaluate the influence of cholesterol depletion in oral squamous cell carcinoma cell line and epithelial-mesenchymal transition process. METHODS: Cholesterol depletion was induced on SCC-9 cells by methyl-ß-cyclodextrin and cell viability, proliferation, apoptosis, and colony formation capacities were evaluated. Gene and protein expressions were evaluated by reverse transcription polymerase chain reaction (RT-qPCR) and Western Blot, respectively, and cell sublocalization was assessed by immunofluorescence. RESULTS: Cholesterol depletion resulted in alteration of oral squamous cell carcinoma cell morphology at different concentrations of methyl-ß-cyclodextrin, as well as decreased cell proliferation and viability rates. Analysis of CAV1 transcript expression revealed increased gene expression in the treated SCC-9 during the 24 h period, at different concentrations of methyl-ß-cyclodextrin: 5 , 7.5, 10, and 15 mM, in relation to parental SCC-9. CAV1 protein expression was increased, with subsequent dose-dependent decrease. A statistically significant difference was observed in samples treated with 5 mM of methyl-ß-cyclodextrin (p = 0.02, Kruskal-Wallis test). The immunofluorescence assay showed lower cytoplasmic and membrane labeling intensity in the treated samples for CAV1. CONCLUSION: These findings indicate the modulation of cholesterol as a possible mechanism underlying the regulation of these molecules and activation of epithelial-mesenchymal transition in oral squamous cell carcinoma.

Effects of amber LED on inflammatory and regulatory monocytes and lymphocytes.

The primary objective of the present study was to assess the impact of amber LED photobiomodulation (PBM) on human monocytes and lymphocytes that were polarized into proinflammatory and regulatory/reparative phenotypes. Human leukocytes were polarized with LPS or LPS + IL-4 for 2 h and irradiated after 2 and 6 h with amber LED (590 nm). Cell absorbance spectrum and gene and protein expression of IL-1ß, IL-6, IL-10, IL-17, TNF-α and IFNγ determined after 24 h. The results showed that irradiation did not significantly alter absorbance of non-polarized monocytes, whereas irradiated polarized monocytes presented reduction in absorbance in 625-850 nm region. Irradiated monocytes polarized with LPS + IL-4 presented reduction in absorbance in 600-725 nm region compared to non-irradiated group. Irradiated non-polarized lymphocytes presented absorbance peaks between 650 and 820 nm not seen in non-irradiated group. No difference was found in absorbance pattern of polarized lymphocytes after irradiation. Irradiation led to reduction in protein synthesis of IL-6 and TNFα in monocytes polarized to proinflammatory phenotype and increase in production of IL-17 in lymphocytes. Irradiation reduced production of IL-10 in monocytes and lymphocytes polarized to immunoregulatory phenotype. In conclusion, amber LED modulates light absorbance and expression of important cytokines in inflammatory/repair processes in monocytes and lymphocytes.

Loss of Caveolin-1 Expression in Tumor Cells is Associated with Increased Aggressiveness and Cell Invasion in Oral Squamous Cell Carcinoma.

BACKGROUND: Changes in Caveolin-1 (CAV-1) expression are related to tumorigenesis. The aim of this study was to evaluate the role of CAV-1 in tumor progression in oral squamous cell carcinoma (SCC) tissue samples and the effect of CAV-1 silencing on two oral tongue SCC (OTSCC) cell lines (SCC-25, from a primary tumor, and HSC-3 from lymph node metastases). METHODS: Mycroarray hybridization, mRNA expression, and immunohistochemistry were performed on OSCC tissue samples and corresponding non-tumoral margin tissues. The effects of CAV-1 silencing (siCAV-1) on cell viability, membrane fluidity, on the expression of epithelial to mesenchymal transition (EMT) markers and on cell migration and invasion capacity of OTSCC cell lines were evaluated. RESULTS: Microarray showed a greater CAV-1 expression (1.77-fold) in OSCC tumors than in non-tumoral tissues and 2.0-fold more in less aggressive OSCCs. However, significant differences in CAV-1 gene expression were not seen between tumors and non-tumoral margins nor CAV-1 with any clinicopathological parameters. CAV-1 protein was localized both in carcinoma and in spindle cells of the tumor microenvironment (TME), and CAV-1 positive TME cells were associated with smaller/more aggressive tumors, independent of the carcinoma cells' expression. Silencing of CAV-1 increased cell viability only in SCC-25 cells. It also stimulated the invasion of HSC-3 cells and increased ECAD and BCAT mRNA in these cells; however, the protein levels of the EMT markers were not affected. CONCLUSION: Decreased expression of CAV-1 by tumor cells in OSCC and an increase in the TME were associated with increased cell invasiveness and tumor aggressiveness.

Secretory carcinoma of the salivary gland is rich in lactoferrin: a possible lactational-like differentiation?

PURPOSE: It has been hypothesised that secretory carcinoma of the salivary gland (SCsg) might have a lactational-like differentiation. Therefore, we aimed to assess the immunoexpression of breast hormonal receptors and milk-related proteins in cases of SCsg and other salivary gland tumours with prominent secretory activity. METHODS: Immunohistochemistry against prolactin and growth hormone receptors, lactoferrin, human milk fat globule 1, MUC 1 and MUC4 was performed in twelve cases of SCsg and 47 other salivary gland tumours. RESULTS: Most cases of SCsg were negative for prolactin and growth hormone receptors. All cases of SCsg showed enhanced membranous-cytoplasmic staining for human milk fat globule 1, a pattern seen in other tumour groups. Only SCsg showed widespread strong staining for lactoferrin, concomitantly in the cell compartment and secretion. The other positive tumour types exhibited restricted staining. MUC1 and MUC4 showed no distinct pattern of expression. CONCLUSION: Although SCsg failed to demonstrate a complete lactational-like differentiation, lactoferrin showed a distinctive expression pattern in SCsg compared to other tumour types, which makes it a good marker to help in its differential diagnosis.

Mechanisms involved in cancer stem cell resistance in head and neck squamous cell carcinoma.

Despite scientific advances in the Oncology field, cancer remains a leading cause of death worldwide. Molecular and cellular heterogeneity of head and neck squamous cell carcinoma (HNSCC) is a significant contributor to the unpredictability of the clinical response and failure in cancer treatment. Cancer stem cells (CSCs) are recognized as a subpopulation of tumor cells that can drive and maintain tumorigenesis and metastasis, leading to poor prognosis in different types of cancer. CSCs exhibit a high level of plasticity, quickly adapting to the tumor microenvironment changes, and are intrinsically resistant to current chemo and radiotherapies. The mechanisms of CSC-mediated therapy resistance are not fully understood. However, they include different strategies used by CSCs to overcome challenges imposed by treatment, such as activation of DNA repair system, anti-apoptotic mechanisms, acquisition of quiescent state and Epithelial-mesenchymal transition, increased drug efflux capacity, hypoxic environment, protection by the CSC niche, overexpression of stemness related genes, and immune surveillance. Complete elimination of CSCs seems to be the main target for achieving tumor control and improving overall survival for cancer patients. This review will focus on the multi-factorial mechanisms by which CSCs are resistant to radiotherapy and chemotherapy in HNSCC, supporting the use of possible strategies to overcome therapy failure.

Voltage-gated sodium channels gene expression in Burning Mouth Syndrome: a case-control study.

Burning mouth syndrome (BMS) is a condition characterized by painful symptoms of the oral mucosa, despite the absence of any clinical signs. Its etiology is unknown, and there is still no effective treatment to date. Current evidence has shown neuropathic impairment in BMS patients. Neuropathic pain can be related to the dysfunction of voltage-gated sodium channels, considering that these receptors regulate the induction of action potentials in nociceptive neurons. This study evaluated the gene expression of voltage-gated sodium channels Na v 1.7, Na v 1.8 and Na v 1.9 in these patients. The gene expressions of these channels were assessed by real time RT-PCR analysis of fresh-frozen tongue biopsies in a case-control study composed of 12 patients with BMS, and 5 healthy control patients, proportionally matched by sex and age, and analyzed using the 2^(-Delta Delta CT) method. There was no statistically significant difference between the analyzed groups, despite the increase in Na v 1.7 (fold-change = 3.13, p = 0.52) and decrease in Na v 1.9 (fold-change = 0.45, p = 0.36) gene expression in the BMS group. The Na v 1.8 gene was not expressed in any of the samples analyzed. Although the gene expression in the voltage-gated sodium channels in BMS under study seems to be comparable with that of the normal oral mucosa, the functionality of these channels in BMS has not yet been identified, thus suggesting that further research is needed to better understand these voltage-gated sodium channels.

Influence of conditioned medium from squamous cell carcinoma of the tongue on lymphoblasts and peripheral blood mononuclear cells.

BACKGROUND: Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the oral cavity and is associated with high morbidity and mortality. Attention has been given to the role of inflammatory cells in carcinogenesis because of the ability of cancer cells to subvert the immune response. However, little is known about how molecules from neoplastic cells interact with lymphoblasts and circulating immune cells. This study aimed to understand the mechanisms by which SCC cells modulate the immune response by analyzing the influence of conditioned medium derived from SCC cell lines on immune cells. METHODS: Lymphoblastic cells (CEM) and peripheral blood mononuclear cells (PBMC) were cultured in a conditioned medium derived from squamous cell carcinoma cells (SCC9 or SCC4) and analyzed for cell viability, CD4/CD8/FOXP3 profile by flow cytometry, and chemokine levels. RESULTS: Conditioned medium derived from SCC4 and SCC9 presented higher concentrations of IL-6 and IL-8 than IL-1ß, IL-10, and IFN-γ. CEM and PBMCs when cultured with conditioned medium derived from SCC4 and SCC9 reduced IL-1ß, IL-8, and IFN-γ concentrations. Conditioned medium from SCC4 increased CD4+ population in both CEM and PBMCs, while in conditioned medium from SCC9 it occurred only in PBMCs. PBMCs when cultured with both conditioned mediums increased CD8+ /FOXP3+ cells. CEM cells when cultured with conditioned medium derived from SCC4 and SCC9 reduced. CONCLUSION: Collectively, our results suggest that the products derived from squamous cell carcinoma on inflammatory cells can promote an immunosuppressed environment by reducing cell viability, changing cytokine expression, and altering the cell immunoprofile.

Voltage-gated sodium channels gene expression in Burning Mouth Syndrome: a case-control study

Abstract Burning mouth syndrome (BMS) is a condition characterized by painful symptoms of the oral mucosa, despite the absence of any clinical signs. Its etiology is unknown, and there is still no effective treatment to date. Current evidence has shown neuropathic impairment in BMS patients. Neuropathic pain can be related to the dysfunction of voltage-gated sodium channels, considering that these receptors regulate the induction of action potentials in nociceptive neurons. This study evaluated the gene expression of voltage-gated sodium channels Na v 1.7, Na v 1.8 and Na v 1.9 in these patients. The gene expressions of these channels were assessed by real time RT-PCR analysis of fresh-frozen tongue biopsies in a case-control study composed of 12 patients with BMS, and 5 healthy control patients, proportionally matched by sex and age, and analyzed using the 2^(-Delta Delta CT) method. There was no statistically significant difference between the analyzed groups, despite the increase in Na v 1.7 (fold-change = 3.13, p = 0.52) and decrease in Na v 1.9 (fold-change = 0.45, p = 0.36) gene expression in the BMS group. The Na v 1.8 gene was not expressed in any of the samples analyzed. Although the gene expression in the voltage-gated sodium channels in BMS under study seems to be comparable with that of the normal oral mucosa, the functionality of these channels in BMS has not yet been identified, thus suggesting that further research is needed to better understand these voltage-gated sodium channels.

Solitary fibrous tumor of the tongue.

Solitary fibrous tumor (SFT) is a benign mesenchymal neoplasm originally described in pleura with a rare presentation in the oral cavity. Herein, we report a case of a 28-year-old male patient who presented an asymptomatic slow-growing mass in the anterior part of the tongue. Intraoral examination revealed a well-circumscribed mass covered by normal mucosa with a fibrous consistency. Due to non-specific clinical findings, the initial diagnostic hypotheses include benign submucosal neoplasms such as leiomyoma, neurofibroma, SFT, and others. An excisional biopsy was performed. Microscopically, the tumor was surrounded by a thick fibrous capsule; hypo and hypercellular areas were arranged in a storiform pattern with a stroma formed by collagen and abundant vascularization. Tumor cells showed immunopositivity for CD34 and STAT-6 and no expression of CD99, AML, S-100, and Ki-67. According to these findings, the diagnosis of SFT was established. After 24 months, the patient is asymptomatic and has no evidence of recurrence. Although oral involvement is rare, SFT should be included in the differential diagnosis of oral submucosal lesions.

The Fagerström and AUDIT Tests as Probable Screening Tools in Oral Cancer and Their Correlation with CYP1A1, GSTM1, GSTP1, and GSTT1 Gene Expression.

BACKGROUND: Cancer is currently a major public health problem worldwide, with a marked increase of about 70% in the number of expected diagnosed cases over the next two decades. The amount of tobacco and alcohol consumed is calculated based on the subjective information provided by the user. Tobacco exposure can be assessed using the Fagerström Test for Cigarette Dependence (FTCD) and alcohol consumption by the Alcohol Use Disorder Identification Test (AUDIT). MATERIALS AND METHODS: Forty-eight subjects answered the Fagerström, and AUDIT tests and we studied them as likely screening tools for oral cancer and their correlation with the expression of CYP1A1, GSTM1, GSTP1, and GSTT1 genes by the RT-qPCR method. RESULTS: There were significant differences in the AUDIT score and CYP1A1 expression between cancer and control groups. Participants in advanced stages, whether due to tumor size or regional metastasis, showed significant differences in the duration of tobacco use, FTCD, AUDIT score, and CYP1A1 expression when compared to patients in early stages. Among subjects without cancer, we found a significant correlation between participant age and GSTP1 expression. Furthermore, the expression of GSTP1 was significantly correlated with the number of cigarettes smoked per day, duration of tobacco use, and FTCD. CONCLUSIONS: Questionnaires designed to evaluate the degree of tobacco and alcohol exposure and dependence combined with gene expression tests can be useful to assess the risk of developing oral cancer. Furthermore, raising the awareness of individuals regarding their degree of dependence and encouraging them to participate in cessation programs are important educational measures for the prevention of tobacco-related malignancies.

Central giant cell granulomas of the jaws stromal cells harbour mutations and have osteogenic differentiation capacity, in vivo and in vitro.

BACKGROUND: Central giant cell granulomas (CGCG) of the jaws are osteolytic lesions that may behave aggressively and respond poorly to surgery. Microscopically, in addition to giant cells, there is a mononuclear cell population composed of macrophage/monocytic cells and spindle-shaped cells of mesenchymal origin. Seventy two percent of these tumours harbour mutually exclusive TRPV4, KRAS and FGFR1 mutations. We aimed to assess the mutational status of mononuclear and giant cells and the osteogenic potential of stromal cells in vitro and in vivo. METHODS AND RESULTS: We screened CGCG for signature mutations and used laser-capture microdissection to demonstrate that the mutations are restricted to the mononuclear cells. Additionally, we established CGCG primary cell culture and observed that the cells retained the mutations throughout passages. By flow cytometry, we observed predominance of CD14- CD51- CD61- cells, consistent with the expected profile for stromal cells. Considering the mesenchymal origin of stromal cells, we assessed the osteogenic differentiation potential of CGCG cells in culture by cytochemistry (von Kossa and alizarin red staining), alkaline phosphatase (ALP) activity assay and gene expression of osteogenic markers. CGCG cells presented self-capacity to increase ALP levels in a time-dependent manner and under osteogenic induction presented increasing number of calcium deposits, and overall higher expression of osteocalcin, RUNX2, ALPL and osteopontin than cells without osteogenic induction. A patient-derived xenograft model for CGCG was established, and osteoid material deposition was observed. CONCLUSION: Collectively, the results confirm that the signature mutations are restricted to stromal cells in CGCG, and the in vitro and in vivo results support that these cells have the capacity to differentiate into osteoblasts, in line with the bone formation often observed in the stroma of these lesions.

Photodynamic therapy for squamous cell carcinoma of the head and neck: narrative review focusing on photosensitizers.

This narrative review aimed to evaluate the effectiveness of PDT in early or advanced squamous cell carcinoma of the head and neck (SCCHN). Scopus, MEDLINE/PubMed, and Embase were searched electronically following the PRISMA protocol. Quality assessment was performed according to JBI, NIH, and AMSTAR protocols. The main outcomes evaluated were treatment response, recurrence, survival, and adverse effects. A total of 49 articles met the search criteria: 43 case series, two cohort studies, two prospective before-after clinical trials, one systematic review, and one meta-analysis. Data from 2121 SCCHN patients were included. The response to PDT was variable according to the type of photosensitizer, tumor location, and tumor stage. In general, higher complete responses rated were observed in T1/T2 SCCHN, mainly with mTHPC-mediated PDT. With regard to T3/T4 or advanced SCCHN tumors, there is no compelling evidence suggesting the effectiveness of PDT. Any adverse effects reported were well tolerated by patients. The present review suggests that PDT is a promising treatment modality for early-stage SCCHN. Although there are limitations due to the low level of evidence of the included studies, we believe that the present review could help to design robust clinical trials to determine the efficacy of PDT in SCCHN.

Solitary fibrous tumor of the tongue

ABSTRACT Solitary fibrous tumor (SFT) is a benign mesenchymal neoplasm originally described in pleura with a rare presentation in the oral cavity. Herein, we report a case of a 28-year-old male patient who presented an asymptomatic slow-growing mass in the anterior part of the tongue. Intraoral examination revealed a well-circumscribed mass covered by normal mucosa with a fibrous consistency. Due to non-specific clinical findings, the initial diagnostic hypotheses include benign submucosal neoplasms such as leiomyoma, neurofibroma, SFT, and others. An excisional biopsy was performed. Microscopically, the tumor was surrounded by a thick fibrous capsule; hypo and hypercellular areas were arranged in a storiform pattern with a stroma formed by collagen and abundant vascularization. Tumor cells showed immunopositivity for CD34 and STAT-6 and no expression of CD99, AML, S-100, and Ki-67. According to these findings, the diagnosis of SFT was established. After 24 months, the patient is asymptomatic and has no evidence of recurrence. Although oral involvement is rare, SFT should be included in the differential diagnosis of oral submucosal lesions.

Influence of nicotine dependence, current smoking status and gender on CYP1A1, CYP1B1 and CYP2A6 expression in oral squamous cell carcinoma / Influência da dependência nicotínica, parâmetros de consumo de tabaco e gênero na expressão de CYP1A1, CYP1B1 e CYP2A6 em carcinoma de células escamosas oral

Objective: Tobacco smoke is composed of cancer-causing chemicals referred to as carcinogens. These carcinogens are metabolized by the enzymes of the cytochrome P450 (CYP) family. Our objective was to evaluate the correlation of tobacco consumption parameters with CYP1A1, CYP1B1 and CYP2A6 expression using qRT-PCR in samples of oral squamous cell carcinoma (OSCC). Material and Methods: The sample was divided into 2 groups: Cancer (36 subjects) and non-Cancer (12 subjects). The smokers' participants (36) were evaluated regarding their Nicotine dependence (ND) was assessed by the Fagerström test for cigarette dependence (FTCD). Questions regarding tobacco consumption like the number of cigarettes/day (CPD), duration of use, and pack-years were also evaluated. The Mann-Whitney and Spearman correlation tests were used at a significance level of 5%. Results: 48 participants were included, 32 men (66.7%), 36 smokers (75%) and 27 smokers with OSCC (56.3%). Samples of OSCC expressed more CYP1A1, CYP1B1, and CYP2A6. Especially, the CYP1B1 gene was significantly expressed in OSCC samples, regardless gender or tobacco use. No women expressed CYP2A6, as well as, non-smokers did not express the CYP1A1 and CYP2A6 genes. CYP1A1 gene was higher among men (P = 0.021). Conclusion: Lack of exposure to tobacco may justify the absence of CYP1A1 and CYP2A6 expression in non-smokers. The CYP1B1 gene was significantly expressed in the cancer presence despite gender or tobacco use. The assessment of ND and quantification of tobacco consumption are important instruments in monitoring smokers with benign oral lesions and, especially, in the presence of cancer.(AU)

Objetivo: A fumaça do tabaco é composta de substâncias químicas cancerígenas conhecidas como carcinógenos. Esses carcinógenos são metabolizados pelas enzimas da família do citocromo P450 (CYP). Nosso objetivo foi avaliar a correlação dos parâmetros do consumo de tabaco com a expressão de CYP1A1, CYP1B1 e CYP2A6 por qRT-PCR em amostras de carcinoma de células escamosas bucal (CCEB). Material e Métodos: A amostra foi dividida em 2 grupos: Câncer (36 indivíduos) e sem Câncer (12 indivíduos). Os participantes fumantes (36) foram avaliados quanto à dependência nicotínica (DN) pelo teste de Fagerström para dependência de cigarro (TFDC). Questões relacionadas ao consumo de tabaco como número de cigarros / dia (CPD), tempo de uso e anos-maço também foram avaliadas. Os testes de correlação de Mann-Whitney e Spearman foram utilizados com nível de significância de 5%. Resultados: foram incluídos 48 participantes, 32 homens (66,7%), 36 fumantes (75%) e 27 fumantes com CCEB (56,3%). Amostras de CCEB expressaram mais CYP1A1, CYP1B1 e CYP2A6. Especialmente, o gene CYP1B1 foi significativamente expresso em amostras de CCEB, apesar do sexo ou uso de tabaco. Nenhuma mulher expressou CYP2A6, assim como, não fumantes não expressaram os genes CYP1A1 e CYP2A6. O gene CYP1A1 foi maior entre os homens (P = 0,021). Conclusão: A falta de exposição pode justificar a ausência da expressão dos genes CYP1A1 e CYP2A6 entre não fumantes. O gene CYP1B1 foi significativamente expresso na presença de câncer, independentemente do sexo ou do uso de tabaco. A avaliação da DN e a quantificação do consumo de tabaco são importantes instrumentos no acompanhamento de fumantes com lesões bucais benignas e, principalmente, na presença de câncer (AU)

Extracellular vesicles cargo from head and neck cancer cell lines disrupt dendritic cells function and match plasma microRNAs.

Extracellular vesicles (EVs) are mediators of the immune system response. Encapsulated in EVs, microRNAs can be transferred between cancer and immune cells. To define the potential effects of EVs originated from squamous cell carcinoma cells on immune system response, we performed microRNA profiling of EVs released from two distinct cell lines and treated dendritic cells derived from circulating monocytes (mono-DCs) with these EVs. We confirmed the internalization of EVs by mono-DCs and the down-regulation of microRNA mRNA targets in treated mono-DCs. Differences in surface markers of dendritic cells cultivated in the presence of EVs indicated that their content disrupts the maturation process. Additionally, microRNAs known to interfere with dendritic cell function, and detected in EVs, matched microRNAs from squamous cell carcinoma patients' plasma: miR-17-5p in oropharyngeal squamous cell carcinoma, miR-21 in oral squamous cell carcinoma, miR-16, miR-24, and miR-181a circulating in both oral and oropharyngeal squamous cell carcinoma, and miR-23b, which has not been previously described in plasma of head and neck squamous cell carcinoma, was found in plasma from patients with these cancer subtypes. This study contributes with insights on EVs in signaling between cancer and immune cells in squamous cell carcinoma of the head and neck.

PAI-1 expression in intratumoral inflammatory infiltrate contributes to lymph node metastasis in oral cancer: A cross-sectional study.

INTRODUCTION: Immune cells contribute with mediators in the protein expression profile of the tumor microenvironment. Levels of plasminogen activator inhibitor-1 (PAI-1) are elevated in non-malignant inflammatory conditions; however, the association between PAI-1 expression and inflammation remains uncertain in oral squamous cell carcinoma (OSCC). This study aimed to investigate PAI-1 expression in mononuclear inflammatory cell infiltrate in OSCC and its role as a prognostic marker. METHODS: Samples were collected from patients with OSCC, treated surgically, and followed for 24 months after the procedure. Thirty-nine tumoral tissue were analyzed using immunohistochemistry. Correlation between protein expression, clinicopathological parameters, and the prognosis was investigated. RESULTS: Positive PAI-1 expression in mononuclear inflammatory cell infiltrate was significantly associated with lymph node status (p = 0.009) and with the cytoplasmic expression of vascular endothelial growth factor A (VEGFA) (p = 0.028). Multivariate analysis revealed weak PAI-1 expression as an independent marker for lymph node metastases, with approximately 8-fold increased risk compared to strong expression (OR = 8.60; CI = 1.54-48.08; p = 0.014). CONCLUSION: Our results suggest that the strong PAI-1 expression in intratumoral inflammatory infiltrate is an indicator of a better prognosis for patients diagnosed with oral squamous cell carcinoma.

Homeobox gene amplification and methylation in oral squamous cell carcinoma.

OBJECTIVES: Investigate the DNA copy number and the methylation profile of the homeobox genes HOXA5, HOXA7, HOXA9, HOXB5, HOXB13, HOXC12, HOXC13, HOXD10, HOXD11, IRX4 and ZHX1, and correlate them with clinicopathological parameters and overall survival. MATERIAL AND METHODS: DNA from OSCC samples and surgical margins were submitted to DNA amplification by qPCR and to DNA methylation analysis using a DNA Methylation PCR Array System. RESULTS: HOXA5, HOXB5 and HOXD10 were amplified in surgical margins while HOXA9, HOXB13 and IRX4 were amplified in OSCC. HOXD10 demonstrated hypermethylation in half of the tumor while ZHX1 did not show hypermethylation. No correlation of DNA copy number or methylation with clinicopathological parameters or survival was observed. CONCLUSION: HOXA9, HOXB13 and IRX4 genes appears to be regulated by amplification and HOXD10 by methylation in OSCC. Further studies are needed to determine the role of these events in OSCC development.

Effects of the phenotypic polarization state of human leukocytes on the optical absorbance spectrum.

This study evaluated the optical absorbance spectrum of human monocytes, neutrophils and lymphocytes polarized, or not, to the inflammatory or immunoregulatory phenotypes. Peripheral human blood leukocytes were isolated and polarized (10 ng/mL) with LPS or IL-4 + LPS for 2 hours. After polarization, cells were washed and incubated for an additional 24 hours (monocytes and lymphocytes) or 12 hours (neutrophils). Next, cells were collected to evaluate the optical absorbance spectrum. The three types of leukocytes exhibited absorbance in the region from 450 to 900 nm, with greater absorbance at wavelengths lower than 570 nm. Lymphocytes had a second region of greater absorbance between 770 and 900 nm. Inflammatory monocytes and lymphocytes showed increased absorbance of blue, green and yellow wavelengths (monocytes), as well as red and infrared wavelengths (monocytes and lymphocytes). Immunoregulatory polarization altered the absorbance of monocytes and lymphocytes very little. Neutrophils treated with LPS or LPS + IL-4 exhibited lower absorbance at wavelengths higher than 575 nm compared to untreated cells. The present findings showed that leukocytes exhibit greater absorbance in regions of the spectrum that have not been much used in photobiomodulation (PBM), and the polarization of these cells can affect their capacity to absorb light. Taken together, these results suggest new perspectives in the use of PBM in the clinical setting depending on the wavelengths and the stage of the inflammatory process.

Histopathological findings and immunohistochemical expression of the stem cell markers CD44, ALDH1, Bmi-1, and Nanog in oral solitary fibrous tumors.

OBJECTIVES: The aim of this study was to evaluate the histomorphologic presentation and the expression of stem cell-related markers in a series of oral solitary fibrous tumors (SFTs). STUDY DESIGN: Histopathological variables and the expression of the standard stem cell markers CD34 and CD99, used for SFT diagnosis, as well as STAT6 were evaluated in 13 oral SFTs. The expression of the cancer stem cell markers CD44, ALDH1, Bmi-1, and Nanog and the tumor suppressor gene p16Ink4a were also investigated. RESULTS: The majority of oral SFTs were circumscribed and characterized by a proliferation of spindle cells arranged in a hyalinized stroma. Only 2 oral SFTs showed >4 mitoses/10 high-power fields. Hypercellularity as well as nuclear and cellular pleomorphism were classified as low and moderate in most of the oral SFTs. All oral SFTs were positive for CD34, STAT6, CD44, ALDH1, Bmi-1, and p16Ink4a. CD99 and Nanog expression was observed in 11 and 10 oral SFT cases, respectively. CONCLUSION: We suggest that STAT6 and ALDH1 have relevant diagnostic value. The expression of CD44, ALDH1, Bmi-1, and Nanog, which is observed in cancer stem cells, may confer advantages to oral SFT cells.

Expression of upstream and downstream targets of mTOR pathway in seven cases of secretory carcinoma of salivary gland origin.

PURPOSE: To investigate the expression of upstream and downstream targets of mTOR signalling pathway in the secretory carcinoma of salivary gland origin (SCsg). METHODS: Seven cases of secretory carcinoma diagnosed by a combination of immunohistochemistry and/or molecular testing were retrieved from our pathology files. For comparison purposes, 27 other salivary carcinomas were selected. Immunohistochemical staining was performed against phospho-Akt, PTEN, phospho-mTOR, phospho-4E-BP, eIF4E and phospho-S6 ribosomal protein. RESULTS: With the exception of Akt, all the other proteins were present at some level in the SCsg and in other salivary carcinomas. PTEN was diffusely expressed in 57.1% of SCsg, but only in 14.8% of other salivary carcinomas. mTOR is expressed in more than half of the cases both for SCsg and other salivary tumour types. Most cases of SCsg showed negative expression for S6 ribosomal protein (71.4%) and 4E-BP1 (57.1%). For both groups evaluated, eIF4E was the most expressed protein. CONCLUSION: SCsg shows different expression patterns for the mTOR signalling molecules, but only eIF4E was highly expressed. This may suggest alternative signalling pathways other than Akt and mTOR in this group of tumours.