MMP-9 and CCR7 as Possible Predictors of Lymph Node Metastasis in Laryngeal Squamous Cell Carcinoma.

Background & Objective: The expression of matrix metalloproteinase-9 (MMP-9) and chemokine receptor 7 (CCR7) is significantly associated with tumor invasion and metastasis. Little is known regarding the potential of these markers in predicting cancer metastasis in Laryngeal Squamous Cell Carcinoma (LSCC). Therefore, this study aimed to dissect the potential of these markers in predicting the lymph node metastasis in LSCC patients. Methods: Sixty tissue samples were obtained from the patients diagnosed pathologically with LSCC who underwent partial or total laryngectomy. The expression of MMP-9 and CCR7 was measured using the immunohistochemistry staining in the tissue samples of LSCC patients. The ROC (receiver operating characteristic) curve was used to determine the most significant cut-off points of expression according to the highest sensitivity and specificity of both the markers to predict the lymph node metastasis in LSCC. Then, the relationship between the clinicopathology features and the expression of MMP-9 and CCR7 was evaluated. Results: The expression of both MMP-9 and CCR7 was significantly correlated with the lymph node metastasis in LSCC (P<0.001). Furthermore, CCR7 expression exhibited the highest prediction accuracy (AUC 95.7%) and sensitivity (100%) in predicting the lymph node metastasis in LSCC compared to that of MMP-9 (AUC 92.9%, sensitivity 90%). We also found that patients with larger tumor size (> 4 cm) had significantly higher expression of MMP-9 and CCR7 (P<0.002 and P<0.001, respectively). The Elevated expression level of CCR7 statistically correlated with higher MMP-9 expression (P<0.001). Conclusion: MMP-9 and CCR7 might be beneficial as predictors of lymph node metastasis in LSCC patients.

Curcumin potentiates laryngeal squamous carcinoma radiosensitivity via NF-ΚB inhibition by suppressing IKKγ expression.

Context: Curcumin has shown efficacy in promoting radiosensitivity combined with radiotherapy. However, the role and mechanism of curcumin on radiosensitivity in laryngeal squamous cell cancer (LSCC) is largely unknown.Objective: The aim of our study is to explore the role of IKKγ-NF-κB signaling in curcumin enhancing LSCC cell radiosensitivity in vitro.Materials and methods: Curcumin and X-ray were used to induce cell DNA damage and apoptosis, or inhibit cell clone formation. IKKγ siRNA and plasmid were used to change IKKγ expression. The CCK8 assay was used to detect cell viability. Clone formation ability was analyzed using a clonogenic assay, cell apoptosis was examined using flow cytometry, an immunofluorescence assay was used to detect DNA damage, while mRNA and protein levels were assayed using real time PCR and western blotting, respectively.Results: Curcumin significantly enhanced irradiation-induced DNA damage and apoptosis, while weakening clone-forming abilities of LSCC cell line Hep2 and Hep2-max. Compared to Hep2 cells, Hep2-max cells are more sensitive to curcumin post-irradiation. Curcumin suppressed irradiation-induced NF-κB activation by suppressing IKKγ expression, but not IKKα and IKKß. Overexpression of IKKγ decreased irradiation-induced DNA damage and apoptosis, while promoting clone-forming abilities of Hep2 and Hep2-max cells. IKKγ overexpression further increased expression of NF-κB downstream genes, Bcl-XL, Bcl-2, and cyclin D1. Conversely, IKKγ silencing enhanced irradiation-induced DNA damage and apoptosis, but promoted clone formation in Hep2 and Hep2-max cells. Additionally, IKKγ silencing inhibited expression of Bcl-XL, Bcl-2, and cyclin D1.Conclusions: Curcumin enhances LSCC radiosensitivity via NF-ΚB inhibition by suppressing IKKγ expression.

The prognostic significance of E-cadherin expression in laryngeal squamous-cell carcinoma: a systematic review.

The aim of this study was to systematically review publications that investigated the prognostic role of E-cadherin immunostaining in patients affected by laryngeal squamous cell carcinoma. An appropriate string was run on PubMed to retrieve articles dealing with this topic. A double cross-check was performed on citations and full-text articles by two authors independently to analyse all manuscripts and perform a comprehensive quality assessment. Among 89 abstracts identified, 13 articles were included. These studies reported on 1,121 patients with histologically confirmed diagnosis of laryngeal squamous cell carcinoma. Overall, there were 10 studies that showed a significant correlation between E-cadherin immunohistochemical expression and at least one of the clinical and histopathological parameters considered by the authors. In particular E-cadherin expression was significantly associated with N stage (five studies), grading (four studies) and disease-free survival/disease-specific survival (six studies). In conclusion, the findings of our review appear similar to the results published by other authors on the putative role of E-cadherin in progression of malignancy. In fact, for laryngeal squamous cell carcinoma it seems that lower levels of E-cadherin correlate with increased tumoural aggressiveness and worse prognosis. Nevertheless, further high-quality prospective studies should be carried out to clarify if E-cadherin expression may be considered as an independent prognostic factor for patients affected by laryngeal cancer.

Association of Smoking and XPG, CYP1A1, OGG1, ERCC5, ERCC1, MMP2, and MMP9 Gene Polymorphisms with the early detection and occurrence of Laryngeal Squamous Carcinoma.

A total of 200 smoking-related laryngeal carcinoma patients with pathology confirmation from the Eye and ENT Hospital and 190 high-risk smokers were included in a survey. All of the participants had a smoking index greater than 400 (cigarettes/day*year.) We obtained data on clinical and baseline characteristics, and peripheral blood was obtained and subjected to DNA extraction to analyse the correlation between smoking and the occurrence of laryngeal carcinoma. We selected candidate genes and SNP fragments that were found to be closely associated with smoking-related tumours in preliminary studies. The selected candidate genes were XPG, CYP1A1, OGG1, ERCC5, ERCC1, MMP2, and MMP9. We then performed SNP sequencing using Sequenom SNP detection technology. Target genes and single nucleotide polymorphism (SNP) fragments were evaluated to analyse the correlation between genotype or allele and smoking-related laryngeal carcinoma and to identify susceptibility genes related to laryngeal carcinoma. The results included four main findings: (1) The smoking index differed significantly between laryngeal cancer patients and control subjects (P=0.0035). The risk of laryngeal cancer was increased among individuals with a smoking index greater than 600 cigarettes/day*year (P=0.03). (2) The smoking index was significantly correlated with the T, N and clinical stages (P<0.05). (3) The polymorphisms CYP1A1-rs1048943, rs4646421, and rs4646422 and MMP9-rs17577 were significantly associated with laryngeal squamous carcinoma (P<0.05). (4) After stratifying the subjects by smoking degree, the GT genotype of ERCC1-rs2298881 was associated with a significantly greater risk of laryngeal carcinoma among heavy smokers (P=0.04). The results suggest that smoking plays an important role in the occurrence and development of laryngeal squamous carcinoma; CYP1A1 and MMP9 might be susceptibility gene SNPs for smoking-related laryngeal carcinoma, and ERCC1 might play an important role in heavy smokers. The results of this study might help identify an early marker for the detection and prevention of laryngeal carcinoma.

DNA demethylation of claudin-4 suppresses migration and invasion in laryngeal squamous carcinoma cells.

Claudin-4 (CLDN4) is a member of the claudin transmembrane protein family, which consists of integral membrane proteins that are components of the epithelial cell tight junctions; these tight junctions regulate movement of solutes and ions through the paracellular space. CLDN4 is also a differentiation marker and is believed to indicate an epithelial phenotype. However, the role of CLDN4 in laryngeal squamous carcinoma is still unclear. Here, we showed that CLDN4 expression was down-regulated in laryngeal squamous carcinoma tissues and negatively correlated with methyl-CpG-binding protein 2. In addition, CLDN4 was hypermethylated in HEp-2 cells. DNA demethylation of CLDN4 by 5-aza-2'-deoxycytidine suppressed migration and invasion of HEp-2 cells, whereas CLDN4 silencing restored the migration and invasion of HEp-2 cells. Therefore, CLDN4 plays a key role in laryngeal squamous carcinoma progression.

The prognostic value of preoperative neutrophils, platelets, lymphocytes, monocytes and calculated ratios in patients with laryngeal squamous cell cancer.

This study was aimed to examine the prognostic value of preoperative neutrophils, platelets, lymphocytes, monocytes and calculated ratios in patients with laryngeal squamous cell cancer (LSCC). From January 2007 to December 2011, 979 patients with LSCC were enrolled in our study. Preoperative neutrophils, platelets, lymphocytes, monocytes, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) were analyzed. Besides well-established clinicopathological prognostic factors, we evaluated the independent prognostic relevance of these hematological parameters by Cox regression models in disease-free survival (DFS) and cancer-specific survival (CSS). We found patients in the highest tertile of NLR (>2.40), PLR (>111.00) were at significantly higher risk of DFS and CSS (P<0.05) compared with those in the lowest tertile after multivariate analysis, whereas presenting significantly higher risk in the lowest tertile of lymphocytes (<1.60×109/L) and LMR (<3.50). Additionally, the tertile category of NLR as well as PLR increased and lymphocytes as well as LMR decreased in shorter DFS and CSS by the Kaplan-Meier method and the log-rank test. In conclusion, this study indicated that preoperative lymphocytes, NLR, PLR and LMR were significantly associated with LSCC progression, DFS and CSS, and these hematological parameters could be considered independent prognostic values for patients with LSCC.

Ki-67 is overexpressed in human laryngeal carcinoma and contributes to the proliferation of HEp2 cells.

Ki-67 is one of the most useful markers to evaluate cell proliferative activity and has been widely used in tumor treatment and research. However, its role in human laryngeal carcinoma remains poorly defined. The aim of the present study was to investigate the expression of Ki-67 in human laryngeal squamous carcinoma and the effect of Ki-67 gene silencing by small interfering (si)RNA on the proliferation of human laryngocarcinoma HEp2 cells. Immunohistochemistry and reverse transcription-quantitative polymerase chain reaction were performed to examine the expression of Ki-67 in human laryngeal squamous carcinoma tissues and adjacent non-cancer tissues from 50 patients with laryngeal squamous carcinoma. RNA interference was used to knock down the expression of Ki-67 in the HEp2 cell line, and the proliferation of the treated cells was observed in vitro. Western blot analysis was used to determine the expression levels of epidermal growth factor receptor (EGFR) and E-cadherin in the treated cells. The expression of Ki-67 in the laryngeal squamous carcinoma tissues was significantly higher than that of the adjacent non-tumor tissues (P=0.028). The high expression of Ki-67 in cancer was significantly correlated with cervical lymph node metastasis and clinical outcomes (all P<0.001). The silencing of Ki-67 resulted in the inhibition of proliferation of the HEp2 human laryngocarcinoma cells (P<0.001). In addition, compared with the control group, the expression levels of EGFR and E-cadherin in the Ki-67 siRNA-treated cells were significantly decreased (P<0.001) and increased (P<0.001), respectively. These results suggested that Ki-67 is important in regulating the proliferation of human laryngocarcinoma HEp2 cells and that the mechanism may at least partially be associated with the upregulation of EGFR and the downregulation of E-cadherin. Overall, Ki-67 can be used as an important indicator for judging clinical progress and estimating prognosis in human laryngeal squamous carcinoma.

Effect and mechanism of miR-34a on proliferation, apoptosis and invasion of laryngeal carcinoma cells.

OBJECTIVE: To discuss the effect and mechanism of miR-34a on the proliferation, apoptosis and invasion of laryngeal carcinoma cells. METHODS: The laryngeal squamous carcinoma Hep2 cells were transiently transfected with miR-34a mimics and miR-34a NC. The MTT, colony-forming assay, Hoechst staining and AnnexinV-PI double staining flow cytometry were employed to detect the effect of miR-34a on the viability and apoptosis of laryngeal squamous carcinoma Hep2 cells; Transwell assay to defect the effect of miR-34a on the migration and invasion of laryngeal squamous carcinoma Hep2 cells; western blot and RT-PCR assay to defect the effect of miR-34a mimics on the expression of survivin and Ki-67 mRNA in laryngeal squamous carcinoma Hep2 cells. RESULTS: Compared with miR-34a NC group, the cell viability in miR-34 mimics group was significantly decreased (P < 0.01), the cell apoptosis rate was significantly increased (P < 0.01), the abilities of cell migration and invasion were significantly reduced (P < 0.01) and the expression of survivin and Ki-67 mRNA was significantly decreased (P < 0.01). CONCLUSIONS: The increased expression of miR-34a can induce the apoptosis of Hep2 laryngeal carcinoma cells and inhibit the cell proliferation and invasion, which is related to the down-regulated expression of survivin and Ki-67.

The anti-tumour activity of rLj-RGD4, an RGD toxin protein from Lampetra japonica, on human laryngeal squamous carcinoma Hep-2 cells in nude mice.

PURPOSE: The objective of this study is to investigate the antiproliferative activity and mechanism of integrin-binding rLj-RGD4 in a Hep-2 human laryngeal carcinoma-bearing nude mouse model. METHODS: Human laryngeal squamous carcinoma cells (Hep-2) were inoculated subcutaneously into the axilla of nude mice to generate a Hep-2 human laryngeal carcinoma-bearing nude mouse model. When the Hep-2 xenograft model was successfully established, the animals were randomly separated into five groups. Three groups were treated with different dosages of rLj-RGD4. Cisplatin was administered to the positive control group, and normal saline (NaCl) was administered to the negative control group for 3 weeks. The body weights and the survival of the nude mice were evaluated, and the volumes and weights of the solid tumours were measured. The mechanism underlying rLj-RGD4 inhibition of tumour growth in transplanted Hep-2 human laryngeal carcinoma-bearing nude mice was evaluated by haematoxylin-eosin (HE) staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling (TUNEL), measurement of intratumoural microvessel density (MVD), Western blotting, and quantitative reverse transcription-polymerase chain reaction (qRT-PCR). RESULTS: The tumour volumes and weights of the treatment groups were reduced compared with the model group, and survival times were improved by rLj-RGD4 treatment in Hep-2 human laryngeal carcinoma-bearing nude mice. The number of apoptotic Hep-2 human cells and intratumoural MVD significantly decreased after the administration of rLj-RGD4. In the xenograft tissue of animals treated with rLj-RGD4, FAK, PI3K, and Akt expression was unaltered, whereas P-FAK, P-PI3K, Bcl-2, P-Akt, and VEGF levels were down-regulated. In addition, activated caspase-3, activated caspase-9, and Bax levels were up-regulated. CONCLUSION: rLj-RGD4 exhibits potent in vivo activity and inhibits the growth of transplanted Hep-2 human laryngeal carcinoma cells in a nude mouse model. Thus, these results indicate that the recombinant RGD toxin protein rLj-RGD4 may serve as a potent clinical therapy for human laryngeal squamous carcinoma.

Clinicopathologic significance and survival of TIP30 expression in laryngeal squamous cell carcinoma.

BACKGROUND: The expression and clinical significance of TIP30 and p53 in laryngeal squamous cell carcinoma (LSCC) have not been investigated. METHOD: We determined immunohistochemically the expression of TIP30 and p53 in surgical specimens from 105 patients with LSCC. Survivals were estimated using the Kaplan-Meier method. RESULTS: TIP30 protein expression in LSCC patients was significantly less in tumor tissues than that of adjacent normal tissues (46.7% vs. 79.0%), while p53 protein expression was significantly increased in LSCC (15.2% vs. 63.8%) compared with adjacent normal tissues. The TIP30 expression levels were also significantly correlated with tumor stage, differentiation, and the presence of lymph nodes. The expression of TIP30 was significantly negatively correlated with that of p53 (r = -0.249, P = 0.010). LSCC patients with lower expression level of TIP30 had a significantly higher recurrence and worse overall survival than those with elevated TIP30 expression (P = 0.014 and P = 0.040, respectively). Furthermore, multivariable analysis found that patients with high expression of TIP30 had a greater than approximately 2.2-fold increased risk for death overall or recurrence than those with low expression of TIP30, supporting that down-regulation of TIP30 expression in tumors may involve in development and progression and predict poor prognosis of patients with LSCC. CONCLUSION: Our results may suggest that down-expression of TIP30 is closely related to carcinogenesis, progression, biological behavior, and prognosis of LSCC.