The present study aimed to evaluate the role of Hedgehog (Hh) molecule expression in association with the clinical aspects of oral squamous cell carcinoma (OSCC), as well as angiogenesis and CD163+ macrophages. Twenty-eight cases of OSCC, nine cases of tumor-free resection margins (TM), and four cases of non-neoplastic oral mucosa (NNM) were submitted to immunohistochemistry to detect proteins Sonic Hedgehog (SHH), Indian Hedgehog (IHH), GLI1, CD163, and CD105. Protein colocalization with respect to SHH/CD163, IHH/CD163, GLI1/CD163, and GLI1/CD105 was assessed by immunohistochemical double staining. In tumor parenchyma, SHH and IHH were present in the cytoplasm of neoplastic cells, while GLI1 was observed in cytoplasm and nucleus. Endothelial cells were found to express SHH, IHH, and GLI1 within CD105+ vessels, and a positive correlation between infiltrating macrophage density (IMD) and microvascular density (MVD) was observed in cases of OSCC and TM. When compared to TM and NNM, the OSCC cases demonstrated higher immunoreactivity for SHH (p = 0.01), IHH (p = 0.39), GLI1 (p = 0.03), IMD (p = 0.0002), and MVD (p = 0.0002). Our results suggest the participation of the Hh pathway in OSCC by way of autocrine and paracrine signaling, in addition to the participation of both SHH and IHH ligands. Endothelial cells were also found to exhibit positivity with respect to Hh pathway components and we surmise that these molecules may play a role in tumor angiogenesis. CD163+ macrophages were also observed to express IHH, a ligand of this pathway, in addition to being associated with tumor neovascularization.
A significant interaction between the MC population and CD34-positive vessels in KCOTs supported the hypothesis that MCs and blood vessels contribute to the stromal scaffold of KCOT.
The aim of this study was to characterize the profile of the proteins involved in the Hedgehog signaling pathway to aid in the understanding of the pathogenesis of oral epithelial dysplasia (OED). The proteins SHH, PTCH1, HHIP, SUFU, GLI1, and cyclin D1 were evaluated by immunohistochemistry in 25 cases of OED, 4 of non-neoplasic oral mucosa, 8 of inflammatory fibrous hyperplasia and 5 of hyperkeratosis. SHH proteins were predominant in OED cases. Although PTCH1 protein was observed in all cases, this molecule was more highly expressed in OED. The inhibitor protein SUFU was present in OED and HHIP protein was overexpressed in OED. GLI1 proteins were predominantly found in the nuclei of epithelial cells in OED. Basal and suprabasal cells in the epithelial lining were positive for cyclin D1 only in OED. In conclusion, comparative analysis of the proteins involved in the Hedgehog pathway suggests that enhanced expression of these proteins can play an important role in the biological behavior of OED.
Proteoglycans are involved in tumor development and may regulate the Hedgehog (HH) pathway. This study aimed to investigate the gene and protein expression of glypican-1 (GPC1), -3 (GPC3), and -5 (GPC5) in oral squamous cell carcinoma (OSCC) and tumor-free lateral margins (TM) and their association with the HH pathway. Quantitative PCR was performed for GPC1, GPC3, GPC5, SHH, PTCH1, SMO, and GLI1 genes in samples of OSCC (n = 31), TM (n = 12), and non-neoplastic oral mucosa (NNM) of healthy patients (n = 6), alongside an immunohistochemical evaluation of GPC1, GPC3, and GPC5 proteins and HH proteins SHH and gliomaassociated oncogene homolog 1 (GLI1). Double staining for GPC3/ SHH, GPC5/SHH, GPC3/tubulin [ac Lys40], GPC5/Tubulin [ac Lys40], and GPC5/GLI1 was also performed. Overexpression of GPC1 and GPC5 in tumor samples and underexpressed levels of GPC3 gene transcripts were observed when compared with TM (standard sample). HH pathway mRNA aberrant expression in OSCC samples and a negative correlation between GPC1 and GPC5 at transcription levels were detected. GPC1 staining was rare in OSCC, but positive cells were found in NNM and TM. Otherwise positive immunostaining for GPC3 and GPC5 was observed in OSCCs, but not in NNM and TM. Blood vessels adjacent to tumor islands were positive for GPC1 and GPC5. Co-localization of GPC3-positive and GPC5-positive cells with SHH and Tubulin [ac Lys40] proteins was noted, as well as of GPC5 and GLI1. The absence of the GPC1 protein in neoplastic cells, underexpression of the GPC3 gene, and co-localization of GPCs and HH proteins may indicate the maintenance of aberrant HH pathway activation in OSCC.
In oral squamous cell carcinoma (OSCC), involvement and activation of the Hedgehog pathway (HH) may be related to epithelial-mesenchymal transition and cell proliferation. The present study aimed to evaluate epithelial-mesenchymal transition and proliferative potential in OSCC cases demonstrating activation of the HH pathway. Twenty-three GLi-1-positive OSCC cases were submitted to immunohistochemical detection of Snail, Slug, N-cadherin, E-cadherin, β-catenin, and MCM3 proteins. Clinicalpathologic immunoexpression data were obtained from the invasion front and tumor islets, and then compared. At the invasion front, OSCC cases presented positive Snail, Slug, and MCM3 expression in the nuclei of tumor cells. Loss of membrane and cytoplasmic expression of E-cadherin and β-catenin was also observed. Positive N-cadherin expression was observed in 31.78% of the cases. GLi-1 immunoexpression was associated with loss of membrane E-cadherin (P < 0.001), membrane β-catenin (P < 0.001), and cytoplasmic β-catenin (P = 0.02) expression. In the tumor islets, we observed nuclear expression of GLi-1, Snail, Slug, and MCM3. E-cadherin and β-catenin showed positivity in tumor cell membranes. Statistically significant positive correlations between GLi-1 and Snail (P = 0.05), E-cadherin (P = 0.01), and cytoplasmic β-catenin (P = 0.04) were found. GLi-1 was associated with clinical staging, while membrane β-catenin expression was related to the presence of metastasis in lymph nodes and to clinical staging. The HH pathway may be involved in regulating the expression of the mesenchymal phenotype. The loss of membrane E-cadherin and β-catenin expression was observed at the tumor front region, whereas cell adhesion protein expression was detected in tumor islets regardless of MCM3.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.