Different regions of oral squamous cell carcinoma (OSCC) have particular histopathological and molecular characteristics limiting the standard tumor−node−metastasis prognosis classification. Therefore, defining biological signatures that allow assessing the prognostic outcomes for OSCC patients would be of great clinical significance. Using histopathology-guided discovery proteomics, we analyze neoplastic islands and stroma from the invasive tumor front (ITF) and inner tumor to identify differentially expressed proteins. Potential signature proteins are prioritized and further investigated by immunohistochemistry (IHC) and targeted proteomics. IHC indicates low expression of cystatin-B in neoplastic islands from the ITF as an independent marker for local recurrence. Targeted proteomics analysis of the prioritized proteins in saliva, combined with machine-learning methods, highlights a peptide-based signature as the most powerful predictor to distinguish patients with and without lymph node metastasis. In summary, we identify a robust signature, which may enhance prognostic decisions in OSCC and better guide treatment to reduce tumor recurrence or lymph node metastasis.

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During the last decade, many studies in Europe and North America have evaluated oral conditions and dental needs in the elderly. Similar information does not exist in Brazil. The aim of this study was to determine the prevalence of oral health and disease in elderly persons living in an institution in the city of Piracicaba, State of São Paulo, Brazil. Of 350 elderly persons, 134 males and 136 females were interviewed and clinically examined. Less than one half had healthy mouths. 58.9% of the examined individuals showed one or more lesions in the oral mucosa, the most frequent being denture-induced stomatitis (20.0%). Fibrous hyperplasias (11.8%) and angular cheilitis (9.3%) were fairly common. Gender, use and degree of hygiene of the denture were factors statistically significantly contributing to prevalence of denture stomatitis. Precancerous lesions such as leukoplakia (3.0%), actinic cheilitis (2.6%) were uncommon but three cases of squamous carcinoma (1.1%) were revealed. This study emphasizes the need for regular oral examinations of the elderly by personnel trained in oral diagnosis.

As one of the most abundant constituents of the tumour microenvironment (TME), cancer-associated fibroblasts (CAF) display critical roles during tumour progression and metastasis. Multiple classes of molecules including growth factors, cytokines, proteases and extracellular matrix proteins, are produced by CAF to act as mediators of the stroma-tumour interactions. One of the main channels for this communication is associated with extracellular vesicles (EV), which are secreted particles loaded with protein and genetic information. In this study, we evaluated the effects of EV derived from CAF primary human cell lines (n = 5) on proliferation, survival, migration, and invasion of oral squamous cell carcinoma (OSCC) cells. As controls, EV from human primary-established normal oral fibroblasts (NOF, n = 5) were used. Our in vitro assays showed that CAF-EV significantly induces migration and invasion of OSCC cells and promote a disseminated pattern of HSC-3 cell invasion in the 3D organotypic assay. Furthermore, gene expression analysis of EV-treated cancer cells revealed changes in the pathways associated with tumour metabolism and up-regulation of tumour invasion genes. Our findings suggest a significant role of CAF-EV in promoting the migration and invasion of OSCC cells, which are related to the activation of cancer-related pathways.

ObjectiveTo analyze the gene and immunohistochemical expression of HIF‐1α, GLUT‐1, FASN, and adipophilin in normal salivary gland (NSG), pleomorphic adenoma (PA), and carcinoma ex pleomorphic adenoma (CXPA) samples.Material and MethodsThe gene expression was investigated by the real‐time PCR (qRT‐PCR) method in 9 samples of frozen tissues of normal salivary gland, 13 PA, and 10 CXPA. We validated the reactions by immunohistochemistry on 20 samples from NSG, 85 PA, and 44 CXPA.ResultsOur results showed that there was no statistically significant difference in HIF‐1α gene and immunohistochemistry expression among the tissues studied while FASN gene and immunohistochemistry expression increased along the carcinogenesis of the PA. GLUT‐1 was significantly more expressed in tumor tissues (PA and CXPA), although protein is mainly expressed in transformed cells than in PA and NSG. In contrast, adipophilin was significantly more expressed in NSG while the expression of the protein increased in PA and CXPA.ConclusionsIn summary, the data presented here suggest that neoplastic cells reprogram the expression of GLUT‐1 and adipophilin to adapt to the tumor microenvironment and reinforce, through immunohistochemical results, a possible transcriptional and post‐translational regulatory mechanisms that act on the expression of these genes.

Anticancer properties of the fatty acid synthase inhibitor TVB-3166 on oral squamous cell carcinoma cell lines

Stanniocalcin 2 (STC2), a glycoprotein that regulates calcium and phosphate homeostasis during mineral metabolism, appears to display multiple roles in tumorigenesis and cancer progression. This study aimed to access the prognostic value of STC2 in oral squamous cell carcinoma (OSCC) and its implications in oral tumorigenesis. STC2 expression was examined in 2 independent cohorts of OSCC tissues by immunohistochemistry. A loss-of-function strategy using shRNA targeting STC2 was employed to investigate STC2 in vitro effects on proliferation, apoptosis, migration, invasion, epithelial-mesenchymal transition (EMT) and possible activation of signaling pathways. Moreover, STC2 effects were assessed in vivo in a xenograft mouse cancer model. High expression of STC2 was significantly associated with poor diseasespecific survival (HR: 2.67, 95% CI: 1.37-5.21, p=0.001) and high rate of recurrence with a hazard ratio of 2.80 (95% CI: 1.07-5.71, p=0.03). In vitro downregulation of STC2 expression in OSCC cells attenuated proliferation, migration and invasiveness while increased apoptotic rates. In addition, the STC2 downregulation controlled EMT phenotype of OSCC cells, with regulation on E-cadherin, vimentin, Snail1, Twist and Zeb2. The reactivation of STC2 was observed in the STC2 knockdown cells in the in vivo xenograft model, and no influence on tumor growth was observed. Modulation of STC2 expression levels did not alter consistently the phosphorylation status of CREB, ERK, JNK, p38, p70 S6K, STAT3, STAT5A/B and AKT. Our findings suggest that STC2 overexpression is an independent marker of OSCC outcome and may contribute to tumor progression via regulation of proliferation, survival and invasiveness of OSCC cells.

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