OCT4 and SOX2 are biomarkers of tumorigenesis and early stage OSCC. SOX2 is an independent prognostic factor for OSCC.

Apoptosis plays a dual role in cancer development and malignancy. The role of apoptosis-related caspases in cancer remains controversial, particularly in oral tongue squamous cell carcinoma (OTSCC). In this study, we examined the protein levels of cleaved caspase-3, caspase-3, caspase-8, and caspase-9 on tissue microarrays consisting of samples from 246 OTSCC patients by immunohistochemistry. Wilcoxon signed-rank test indicated that the protein levels of cleaved caspase-3, caspase-3, caspase-8, and caspase-9 in tumor tissues were significantly higher compared to those in adjacent normal tissues (all p<0.001). The expression level of caspase-8 in tumors was elevated in patients with lymph node invasion. Moreover, positive expression of cleaved caspase-3 was associated with shorter disease-free survival (DFS) in OTSCC patients with moderate differentiation and lymph node invasion. Combination of either positive cleaved caspase-3 or higher caspase-3 expression or both was associated with poor DFS. Interestingly, stratification analysis showed that co-expression levels of positive cleaved caspase-3 or/and higher caspase-3 were associated with better disease-specific survival in patients with advanced stages of the disease, such as large tumor size and lymph node invasion, whereas it was associated with poor DFS in OTSCC patients with moderate cell differentiation and small tumor size. Taken together, cleaved caspase-3 and caspase-3/8/9 could be biomarkers for tumorigenesis in OTSCC patients. The co-expression level of cleaved caspase-3 and caspase-3 might be a prognostic biomarker for OTSCC patients, particular in those patients with certain tumor stages and cell differentiation status.

We aimed to investigate the association of the expression levels of five epithelial–mesenchymal transition (EMT)-related proteins (Snail, Twist, E-cadherin, N-cadherin, and Vimentin) with tumorigenesis, pathologic parameters and prognosis in tongue squamous cell carcinoma (TSCC) patients by immunohistochemistry of tissue microarray. The expression levels of Snail, E-cadherin, N-cadherin and Vimentin were significantly different between the tumor adjacent normal and tumor tissues. In tumor tissues, lower E-cadherin and higher N-cadherin levels were associated with a higher grade of cell differentiation, advanced stage of disease, and lymph node metastasis. However, higher Vimentin expression was associated with poor cell differentiation and lymph node metastasis. Patients with low E-cadherin expression had poor disease-specific survival (DSS). Conversely, positive N-cadherin and higher Vimentin expression levels were associated with poor DSS and disease-free survival. Notably, our multivariate Cox regression model indicated that high Vimentin expression was an adverse prognostic factor for DSS in TSCC patients, even after the adjustment for cell differentiation, pathological stage, and expression levels of Snail, Twist, E-cadherin, and N-cadherin. Snail, E-cadherin, N-cadherin, and Vimentin were associated with tumorigenesis and pathological outcomes. Among the five EMT-related proteins, Vimentin was a potential prognostic factor for TSCC patients.

Buccal mucosa squamous cell carcinoma (BMSCC) is the most common oral cancer in Southeast Asia. Caspase-3, a key molecule in regulating apoptosis, promotes the malignancy of various cancers. However, its role in BMSCC is unknown. Herein, we evaluated the association of caspase-3 expression with tumorigenesis and prognosis in BMSCC patients. Immunohistochemical staining indicated that the expression levels of cleaved caspase-3 (p<0.001) and caspase-3 (p<0.001) in 185 BMSCC tissues were significantly higher compared to those in the tumor adjacent normal tissues. Moreover, the high expression of caspase-3 was associated with poor pathological outcomes [advanced pathological stage (p=0.029) and larger tumor size (p=0.002)] and poor disease-free survival in patients receiving postoperative radiotherapy (p=0.030). Moreover, the low co-expression of cleaved caspase-3 and caspase-3 was associated with better disease-specific survival in patients with early pathological stage (I + II, p=0.018) or without lymph node invasion (p=0.043) compared to the positive/high expression of either or both cleaved caspase-3 and caspase-3. Taken together, cleaved caspase-3 and caspase-3 could be biomarkers for tumorigenesis in BMSCC patients. Cleaved caspase-3 and/or caspase-3 might be prognostic biomarkers for certain stages of BMSCC.

Background Type V collagen (COL5), in the functional heterotrimer [α1(V)2α2(V)] isoform, participates in the malignancies of various cancers. However, its role in tongue squamous cell carcinoma (TSCC) remains unclear. Materials and Methods The expression levels of COL5A1 and COL5A2 polypeptide chains were examined using the tissue microarray from 245 TSCC patients with immunohistochemistry. Paired t test and Wilcoxon signed‐rank test were performed for comparisons among the groups. Survival rates were estimated by using the Kaplan‐Meier method and compared with log‐rank tests. A Cox proportional hazards model was used to evaluate the impact of protein expression level on survival rate. Results Expression level of COL5A1 was significantly increased in tumor tissues (P < 0.001) compared to that in corresponding adjacent normal tissues. High expression level of COL5A1 was associated with advanced pathological stage (III, IV, P = 0.015) and lymph node metastasis (P = 0.005) of TSCC patients. High expression level of COL5A1 was also correlated with poor disease‐specific survival (DSS, P = 0.001) and disease‐free survival (DFS, P = 0.003) in TSCC patients. However, high expression level of COL5A2 was correlated with better DFS in TSCC patients (P = 0.043). Moreover, co‐expression level of high (COL5A1)2/low (COL5A2) heterotrimer was correlated with worse DSS (P = 0.004) and DFS (P = 0.004). Conclusion COL5A1 is an unfavorable factor for tumorigenesis, clinicopathological outcomes, and prognosis, whereas COL5A2 is only a favorable factor for prognosis in TSCC. The co‐expression of high (COL5A1)2/low (COL5A2) heterotrimer is a more potential unfavorable factor for prognosis in TSCC.