BackgroundThe composition of the matrix molecules is important in in vitro cell culture experiments of e.g. human cancer invasion and vessel formation. Currently, the mouse Engelbreth-Holm-Swarm (EHS) sarcoma -derived products, such as Matrigel®, are the most commonly used tumor microenvironment (TME) mimicking matrices for experimental studies. However, since Matrigel® is non-human in origin, its molecular composition does not accurately simulate human TME. We have previously described a solid 3D organotypic myoma disc invasion assay, which is derived from human uterus benign leiomyoma tumor. Here, we describe the preparation and analyses of a processed, gelatinous leiomyoma matrix, named Myogel.MethodsA total protein extract, Myogel, was formulated from myoma. The protein contents of Myogel were characterized and its composition and properties compared with a commercial mouse Matrigel®. Myogel was tested and compared to Matrigel® in human cell adhesion, migration, invasion, colony formation, spheroid culture and vessel formation experiments, as well as in a 3D hanging drop video image analysis.ResultsWe demonstrated that only 34 % of Myogel’s molecular content was similar to Matrigel®. All test results showed that Myogel was comparable with Matrigel®, and when mixed with low-melting agarose (Myogel-LMA) it was superior to Matrigel® in in vitro Transwell® invasion and capillary formation assays.ConclusionsIn conclusion, we have developed a novel Myogel TME matrix, which is recommended for in vitro human cell culture experiments since it closely mimics the human tumor microenvironment of solid cancers.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-015-1944-z) contains supplementary material, which is available to authorized users.

Aims: Previous studies have demonstrated that tumor-stroma ratio (TSR) and tumor budding are of prognostic value for oral squamous cell carcinomas (OSCC). Herein we evaluated the prognostic significance of those histological parameters, individually and in combination, for OSCC.Methods: TSR and tumor budding (the presence of ≥ 5 buds at the invasive front) were estimated in 254 patients with OSCC. The clinicopathological association was investigated using a chi-square test, and the prognostic significance (cancer-specific survival and disease-free survival) was verified by Kaplan-Meier analysis and the Cox proportional hazard model.Results: TSR (≥ 50%, stroma-rich) was significantly and independently associated with both shortened cancer-specific survival and poor disease-free survival, whereas tumor budding significantly reduced cancer-specific survival. The TSR/tumor budding model was independently associated with a high-risk of cancer-mortality and recurrence (disease-free survival). In patients with early-stage tumors (clinical stage I and II, n=103), TSR, tumor budding and the TSR/tumor budding model were significantly associated with both cancer-related death and recurrence, while in advanced-stage tumors (clinical stage III and IV, n=144), only TSR and the TSR/tumor budding model were significantly associated with cancer-specific survival.Conclusions: TSR, tumor budding and their combination provide significant information on OSCC outcome, suggesting that their incorporation into the routine evaluation of histopathological specimens might be useful in the prognostication of OSCC patients.

Deregulated expression of activin A is reported in several tumors, but its biological functions in oral squamous cell carcinoma (OSCC) are unknown. Here, we investigate whether activin A can play a causal role in OSCCs. Activin A expression was assessed by qPCR and immunohistochemistry in OSCC tissues. Low activin A-expressing cells were treated with recombinant activin A and assessed for apoptosis, proliferation, adhesion, migration, invasion and epithelial-mesenchymal transition (EMT). Those phenotypes were also evaluated in high activin A-expressing cells treated with follistatin (an activin A antagonist) or stably expressing shRNA targeting activin A. Transfections of microRNA mimics were performed to determine whether the overexpression of activin A is regulated by miR-143/miR-145 cluster. Activin A was overexpressed in OSCCs in comparison with normal oral mucosa, and high activin A levels were significantly associated with lymph node metastasis, tumor differentiation and poor survival. High activin A levels promoted multiple properties associated with malignant transformation, including decreased apoptosis and increased proliferation, migration, invasion and EMT. Both miR-143 and miR-145 were markedly downregulated in OSCC cell lines and in clinical specimens, and inversely correlated to activin A levels. Forced expression of miR-143 and miR-145 in OSCC cells significantly decreased the expression of activin A. Overexpression of activin A in OSCCs, which is controlled by downregulation of miR-143/miR-145 cluster, regulates apoptosis, proliferation and invasiveness, and it is clinically correlated with lymph node metastasis and poor survival.

Oral squamous cell carcinoma (OSCC) prognosis is related to clinical stage and histological grade. However, this stratification needs to be refined. We conducted a comparative proteome study in microdissected samples from normal oral mucosa and OSCC to identify biomarkers for malignancy. Fascin and plectin were identified as differently expressed and both are implicated in several malignancies, but the clinical impacts of aberrant fascin and plectin expression in OSCCs remains largely unknown. Immunohistochemistry and real-time quantitative PCR were carried out in ex vivo OSCC samples and cell lines. A loss-of-function strategy using shRNA targeting fascin was employed to investigate in vitro and in vivo the fascin role on oral tumorigenesis. Transfections of microRNA mimics were performed to determine whether the fascin overexpression is regulated by miR-138 and miR-145. We found that fascin and plectin are frequently upregulated in OSCC samples and cell lines, but only fascin overexpression is an independent unfavorable prognostic indicator of disease-specific survival. In combination with advanced T stage, high fascin level is also an independent factor of disease-free survival. Knockdown of fascin in OSCC cells promoted cell adhesion and inhibited migration, invasion and EMT, and forced expression of miR-138 in OSCC cells significantly decreased the expression of fascin. In addition, fascin downregulation leads to reduced filopodia formation and decrease on paxillin expression. The subcutaneous xenograft model showed that tumors formed in the presence of low levels of fascin were significantly smaller compared to those formed with high fascin levels. Collectively, our findings suggest that fascin expression correlates with disease progression and may serve as a prognostic marker and therapeutic target for patients with OSCC.

Candida albicans is considered the most important Candida species able to cause oral infections in denture wearers. In recent years, Candida dubliniensis has emerged as a pathogenic yeast in humans. The close phenotypic similarities of C. albicans and C. dubliniensis have led to the misidentification of these species. In this work, our aim was to verify through PCR the presence of C. dubliniensis in palate and maxillary denture samples from 112 denture wearers presenting with or without denture-related stomatitis (DRS). C. dubliniensis was isolated at low rates from both palate (5.3 % and 10.7 %) and maxillary denture (5.3 % and 8.9 %) samples from wearers regardless of the presence of the disease. However, when C. dubliniensis was detected in individuals with DRS, it was always associated with C. albicans. In addition, our results showed that C. albicans was the most commonly identified candidal species in maxillary denture and hard palate samples from DRS patients (78.5 % and 89.2 %, respectively) as well as from controls (31.2 % and 28.5 %, respectively). In conclusion, C. dubliniensis was detected in the oral environment of denture wearers. The association of C. dubliniensis with C. albicans occurred in approximately 10 % of the DRS cases. INTRODUCTIONDenture-related stomatitis (DRS) is a local recurring disease (Budtz-Jorgensen et al., 1975;Dar-Odeh & Shehabi, 2003) that attacks the mucosal area subjacent to dental prostheses, beneath the fitting surface of the denture, especially maxillary dentures. Many studies have discussed the involvement of Candida albicans in the establishment and persistence of such disease since the acrylic denture fitting surfaces seem to facilitate the adherence of this micro-organism (Webb et al., 1998;Makihira et al., 2002;Ramage et al., 2004;Moura et al., 2006). Non-albicans Candida species can also be obtained from DRS lesions (Figueiral et al., 2007).Recently, a newly identified Candida species has emerged, Candida dubliniensis, which exhibits numerous characteristics typical of C. albicans species, including the formation of green colonies on CHROMagar medium. Both microorganisms share several phenotypic traits such as the ability to form true germ tubes, adhere to epithelial surfaces, secrete a range of aspartic proteinases and form chlamydospores (Martinez et al., 2002;Sullivan & Coleman, 1998;Sahand et al., 2005; Gilfillan et al., 1998). C. dubliniensis was first obtained from oropharyngeal lesions of human immunodeficiency virus (HIV)-positive patients (Sullivan & Coleman, 1998). Diabetic HIV-negative individuals also exhibited a high prevalence of C. dubliniensis in oral carriage and disease states (Willis et al., 2000). Recent work has documented the presence of C. dubliniensis in just one case of DRS lesion (Mosca et al., 2005). The association between C. dubliniensis and DRS suggests that this microorganism may play important roles in the establishment and persistence of DRS.Therefore, in this work, we examined the presence of C. dubliniensis in samples from palate ...