ABSTRACT
@#[Abstract] Objective:To detect the expression of transcription factor FOXP4 (Forkhead box P4) in laryngeal squamous cell carcinoma (LSCC) tissues and cell lines, and to investigate its effects on the proliferation, migration, invasion, cell cycle, and apoptosis of LSCC TU177 cells in vitro as well as to explore its relationship with epithelial-mesenchymal transition (EMT) process. Methods: A total of 40 pairs of tumor tissues and adjacent tissues that resected from LSCC patients were collected from the biological specimen bank of the Forth Hospital of Hebei Medical University between 2013 and 2015. The expression of FOXP4 in LSCC tissues and corresponding adjacent tissues was detected by qPCR. qPCR and Western blotting were used to detect the FOXP4 expression level in human LSCC cell lines (AMC-HN-8, TU177, TU686, and TU212). Small interfering RNA (si-RNA) was used to knock down FOXP4 expression in TU177 cells. The effects of FOXP4 knockdown on the proliferation, migration, invasion, cell cycle and apoptosis of TU177 cells were measured by MTS assay, clone formation assay, Transwell chamber migration and invasion assay, and flow cytometry, respectively. The mRNA levels of EMT markers N-cadherin, β-catenin, Vimentin, Twist, Snail and zine finger E box binding homeobox 1 (ZEB1) after transfection of si-FOXP4 in TU177 cells were detected by qPCR. The changes of protein levels of N-cadherin, β-catenin, Vimentin and Twist after FOXP4 knockdown were measured by Western blotting. Results: The expression of FOXP4 in LSCC tissues was significantly higher than that in adjacent tissues (P<0.05), and it was related to the TNM stage of tumors and lymph node metastasis (all P<0.05). The expression of FOXP4 in LSCC cells was higher than that in the adjacent tissues (P<0.05 or P<0.01). The expression of FOXP4 in TU177 cells transfected with si-FOXP4 was significantly lower than that in the control group (P<0.01). Compared with the control group, knocking down FOXP4 could inhibit the proliferation, migration and invasion but promote the apoptosis of TU177 cells in vitro (all P<0.01), block the cell cycle at G0/G1 phase (P<0.01), and reduce cell replication in S phase (P<0.01); in addition, knocking down FOXP4 could reduce the mRNA levels of N-cadherin, β-catenin, Vimentin, Twist, Snail, ZEB1 (P<0.05 or P<0.01) and the protein levels of N-cadherin, β-catenin, Vimentin, Twist in TU177 cells. Conclusion: The high expression of FOXP4 may be related to the occurrence and development of LSCC. FOXP4 knockdown can inhibit the proliferation, migration and invasion of laryngeal cancer cells in vitro, block cell cycle at G0/G1 phase, promote apoptosis, and may participate in the EMT process.
ABSTRACT
@# Objective: To explore the expressions of melanoma antigen (MAGE) -A9, -A11 and Ki67 in laryngeal squamous cell carcinoma (LSCC) tissues, and to analyze their correlation with clinicopathological features and the prognosisof LSCC patients. Methods: A total of 73 pairs of LSCC tissuesand corresponding para-cancerous tissues resected from LSCC patients, who were treated at the Fourth Hospital of Hebei Medical University from 2012 to 2014,were collected for this study. At the same time, testicular tissues from 3 patients with prostate cancer after castration were selected as positive control. The protein expressions of MAGE-A9, MAGE-A11 and Ki67 in LSCC tissues and its para-cancerous tissues were detected by immunohistochemistry. Results: The expression rates of MAGEA9, MAGE-A11 protein and Ki67 in LSCC tissues were 47.94% (35/73), 49.32% (36/73) and 46.58% (34/73) respectively, which were significantly higher than those in para-cancerous tissues. The protein expressions of MAGE-A9 and MAGE-A11 were correlated with clinical stage and lymphatic metastasis of LSCC (P<0.05). The expression of Ki67LI was correlated with tumor size, clinical stage and lymphatic metastasis of LSCC (P<0.05). The correlation analysis showed that the expressions of MAGE-A9 and MAGE-A11 were positively correlated with Ki67 (r=0.258, P＝0.027; r=0.672, P=0.001). Kaplan-Meier survival curve analysis showed that the survival rates of patients with high expression of MAGE-A9 protein (P=0.009), MAGE-A11 protein (P=0.031) and Ki67LI (P=0.040) were significantly lower than those with low expressions. And the survival time of patients with both high expressions of MAGE-A9 and Ki67LI (P=0.001) or both high expressions of MAGE-A11 and Ki67 (P=0.001) was significantly shorter than that of patients with low expression (both or single). Univariate and multivariate Cox regression analysis further indicated that MAGE-A9 protein (P=0.028) and MAGE-A11 protein (P=0.042) were independent prognostic factors for overall survival of LSCC patients. Conclusion: MAGE-A9, MAGE-A11 and Ki67 are tumor-associated antigens of LSCC, which can be used as prognostic indicators for LSCC.