Cyclin D1 overexpression in esophageal cancer from southern China and its clinical significance

Discovery of Anticancer Activity of Amentoflavone on Esophageal Squamous Cell Carcinoma: Bioinformatics, Structure-Based Virtual Screening, and Biological Evaluation

Esophageal squamous cell carcinoma (ESCC) is the most common primary esophageal malignancy with poor prognosis. Here, due to the necessity for exploring potential therapies against ESCC, we obtained the gene expression data on ESCC from the TCGA and GEO databases. Venn diagram analysis was applied to identify common targets. The protein-protein interaction network was constructed by Cytoscape software, and the hub targets were extracted from the network via cytoHubba. The potential hub nodes as drug targets were found by pharmacophore-based virtual screening and molecular modeling, and the antitumor activity was evaluated through in vitro studies. A total of 364 differentially expressed genes (DEGs) in ESCC were identified. Pathway enrichment analyses suggested that most DEGs were mainly involved in the cell cycle. Three hub targets were retrieved, including CENPF, CCNA2 (cyclin A), and CCNB1 (cyclin B1), which were highly expressed in esophageal cancer and associated with prognosis. Moreover, amentoflavone, a promising drug candidate found by pharmacophore-based virtual screening, showed antiproliferative and proapoptotic effects and induced G1 in esophageal squamous carcinoma cells. Taken together, our findings suggested that amentoflavone could be a potential cell cycle inhibitor targeting cyclin B1, and is therefore expected to serve as a great therapeutic agent for treating esophageal squamous cell carcinoma.

Expression of cell cycle-related proteins in oropharyngeal squamous cell carcinoma based on human papilloma virus status

The molecular association between human papilloma virus (HPV) and cell cycle-related (CCR) proteins is not fully understood in oropharyngeal squamous cell carcinoma (OPSCC). Herein, we examined the expression levels of CCRs in OPSCCs based on HPV status. In situ hybridization (ISH)- and polymerase chain reaction (PCR)-based assays were used to detect HPV status in 98 OPSCCs, and CCRs were detected by immunostaining. Of 98 tumors, 47 had HPV-positive tumors by either ISH- or PCR-based assays. Concordance analysis between ISH- and PCR-based tests showed a good agreement in OPSCC. Expression of p16 was moderate, consistent with HPV positivity as determined by ISH-based analysis. High p53-, phospho (p)-Rb-, SKP2-, cyclin D1-, and p-c-myc-positive rates were correlated with HPV-negative tumors, whereas high p16- and p27-positive rates were associated with HPV-positive tumors. The positive rates for p21 and cyclin A did not differ between HPV-positive and HPV-negative tumors. Finally, Ki-67 positivity was commonly observed for both types of OPSCCs. Although expression of p16 is thought to be a marker of HPV infection, ISH- or PCR-based tests should be used for HPV detection. In addition, our results regarding CCRs may be helpful for understanding the carcinogenesis of OPSCC.

Metformin induces degradation of cyclin D1 via AMPK/GSK3β axis in ovarian cancer

Metformin, which is widely used as an anti-diabetic drug, reduces cancer related morbidity and mortality. However, the role of metformin in cancer is not fully understood. Here, we first describe that the anti-cancer effect of metformin is mediated by cyclin D1 deregulation via AMPK/GSK3β axis in ovarian cancer cells. Metformin promoted cytotoxic effects only in the cancer cells irrespective of the p53 status and not in the normal primary-cultured cells. Metformin induced the G1 cell cycle arrest, in parallel with a decrease in the protein expressions of cyclin D1 without affecting its transcriptional levels. Using a proteasomal inhibitor, we could address that metformin-induced decrease in cyclin D1 through the ubiquitin/proteasome process. Cyclin D1 degradation by metformin requires the activation of GSK3β, as determined based on the treatment with GSK3β inhibitors. The activation of GSK3β correlated with the inhibitory phosphorylation by Akt as well as p70S6K through AMPK activation in response to metformin. These findings suggested that the anticancer effects of metformin was induced due to cyclin D1 degradation via AMPK/GSK3β signaling axis that involved the ubiquitin/proteasome pathway specifically in ovarian cancer cells. © 2016 Wiley Periodicals, Inc.

Cyclin D1 G870A polymorphism and risk of nasopharyngeal carcinoma: a case-control study and meta-analysis

Background

Cyclin D1 (CCND1) plays a key role in cell cycle regulation. It is a well-established human oncogene which is frequently amplified or overexpressed in cancers. The association between CCND1 G870A polymorphism and cancer risk has been widely assessed. However, a definitive conclusion between CCND1 G870A polymorphism and risk of nasopharyngeal carcinoma (NPC) remains elusive.

Methods

We firstly performed a hospital-based case-control study involving 165 NPC cases and 191 cancer-free controls in central-south China, and then conducted a meta-analysis with six case-control studies to evaluate the association between NPC risk and CCND1 G870A polymorphism.

Results

The case-control study found a significant association between CCND1 G870A polymorphism and NPC risk in various comparison models (AA vs. GG: OR = 2.300, 95% CI 1.089–4.857, p = 0.029; AG vs. GG: OR = 2.832, 95% CI 1.367–5.867, p = 0.005; AA/AG vs. GG: OR = 2.597, 95% CI 1.288–5.237, p = 0.008; AA vs. AG/GG: OR = 0.984, 95% CI 0.638–1.518, p = 0.944). Further meta-analysis showed that there was no significant association between CCND1 G870A polymorphism and NPC risk in overall analysis. In the stratified analysis by race, however, significant associations were only found in Caucasians (for the allele model A vs. G: OR = 0.75, 95% CI 0.59–0.97, p = 0.03; for the co-dominant model AA vs. GG: OR = 0.52, 95% CI 0.32–0.86, p = 0.01; for the dominant model AA/AG vs. GG: OR = 0.49, 95% CI 0.32–0.74, p<0.01; for the recessive model AA vs. AG/GG: OR = 0.90, 95% CI 0.61–1.34, p = 0.60).

Conclusions

A significant association between CCND1 G870A polymorphism and NPC risk was found in the central-southern Chinese population. The meta-analysis indicated that CCND1 G870A polymorphism may contribute to the development of NPC in Caucasians.

Antiproliferative and apoptotic effects of Sesbania grandiflora leaves in human cancer cells

Natural phytochemicals and their derivatives are good drug candidates for anticancer therapeutic approaches against multiple targets. We report here the initial findings from our studies on the anticancer properties of the leaves of the medicinal plant Sesbania grandiflora. In the current study, five different solvent fractions from the leaves of S. grandiflora were tested on cancer cell lines such as MCF-7, HepG2, Hep-2, HCT-15, and A549. The methanolic fraction of S. grandiflora was found to exert potent antiproliferative effects especially in the human lung cancer cell line, A549. Caspase 3 was activated in the methanolic fraction treated A549 cells thereby leading to cell death by apoptosis. DAPI staining, DNA laddering, and decrease in mitochondrial membrane potential further confirmed the apoptotic mode of cell death. The high levels of ROS intermediates as evidenced by DCF-DA staining could have played a role in the apoptotic induction. Decrease in levels of cyclin D1 and decrease in the activation of NFkB were observed in A549 cells on treatment with methanolic fraction, giving a hint on the possible mechanism of action. These results prove that the medicinal plant S. grandiflora can be explored further for promising candidate molecules to combat cancer, especially lung cancer.

Stimulation of the proliferation of human normal esophageal epithelial cells by fumonisin B1 and its mechanism

Previous epidemiological studies have demonstrated a correlation between fumonisin B₁ (FB₁) and human esophageal cancer in China, Iran and South Africa. The purpose of this study was to investigate the effects of FB₁ on the proliferation, cell-cycle and apoptosis of normal human esophageal epithelial cells (HEECs) and to explore the molecular mechanisms of these effects. The proliferation of HEECs treated with FB₁ was assessed using a colorimetric assay, while analyses of the cell cycle and apoptosis were performed using flow cytometry and the measurement of the protein expressions of genes associated with the cell cycle was conducted using western blotting. The results showed that FB₁ stimulated the proliferation of HEECs, decreased the percentage of cells in the G0/G1 phase and reduced apoptosis. The western blotting results showed that FB₁ significantly increased the protein expression of cyclin D1 and significantly decreased the protein expression of cyclin E, p21 and p27. The results indicated that FB₁ stimulated the proliferation of HEECs by affecting the cell cycle and apoptosis. This mechanism was associated with changes in cyclin D1, cyclin E, p21 and p27 expression.

Heterogeneity of 11q13 region rearrangements in laryngeal squamous cell carcinoma analyzed by microarray platforms and fluorescence in situ hybridization

We reinvestigated rearrangements occurring in region q13 of chromosome 11 aiming to: (i) describe heterogeneity of the observed structural alterations, (ii) estimate amplicon size and (iii) identify of oncogenes involved in laryngeal cancer progression as potential targets for therapy. The study included 17 cell lines derived from laryngeal cancers and 34 specimens from primary laryngeal tumors. The region 11q13 was analyzed by fluorescence in situ hybridization (FISH), array comparative genomic hybridization (aCGH) and gene expression microarray. Next, quantitative real time PCR was used for chosen genes to confirm results from aCGH and gene expression microarray. The observed pattern of aberrations allows to distinguish three ways, in which gain and amplification involving 11q13 region may occur: formation of a homogeneously staining region; breakpoints in/near 11q13, which lead to the three to sevenfold increase of the copy number of 11q13 region; the presence of additional copies of the whole chromosome 11. The minimal altered region of gain and/or amplification was limited to ~1.8 Mb (chr.11:69,395,184-71,209,568) and comprised mostly 11q13.3 band which contain 12 genes. Five, out of these genes (CCND1, ORAOV1, FADD, PPFIA1, CTTN) had higher expression levels in comparison to healthy controls. Apart from CCND1 gene, which has an established role in pathogenesis of head and neck cancers, CTTN, ORAOV1 and FADD genes appear to be oncogene-candidates in laryngeal cancers, while a function of PPFIA1 requires further studies.

Decreased expression of CIAPIN1 is correlated with poor prognosis in patients with esophageal squamous cell carcinoma

BACKGROUND

CIAPIN1, a newly identified antiapoptotic molecule, is a downstream effector of the receptor tyrosine kinase-Ras signaling pathway in the mouse Ba/F3 pro-B cell line. Neither CIAPIN1 expression nor its clinical significance has been previously examined in esophageal squamous cell carcinoma (ESCC), and the present immunohistochemical analysis is the first study on CIAPIN1 distribution in ESCC.

AIMS

To investigate the relationships between the expression of CIAPIN1 and clinicopathological characteristics of ESCC, and evaluate the relationship between the expression of this gene and prognosis in ESCC patients.

METHODS

The expression of CIAPIN1 was investigated in 112 surgically resected specimens of ESCC by immunohistochemistry using a specific monoclonal antibody. The relations of CIAPIN1 expression with clinicopathological characteristics and the postoperative survival rate were statistically analyzed.

RESULTS

We found that the expression of CIAPIN1 was statistically correlated with the degree of differentiation, depth of invasion, and lymph node metastasis of ESCC. Consistently, the survival rates of patients with CIAPIN1-negative tumors tended to be statistically lower than those with CIAPIN1-positive tumors. However, no significant difference was observed between CIAPIN1 expression and the patient age, sex, tumor location, and distant metastasis. Furthermore, multivariate analysis was performed by using Cox's proportional hazards model, and the results showed that lymph node metastases and CIAPIN1 expression were two independent prognostic factors.

CONCLUSIONS

CIAPIN1 might play an important role in esophageal carcinogenesis, and it could be considered as a valuable prognostic indicator in ESCC. Finally, functional enhancement of CIAPIN1 might lead to a novel strategy for the treatment of SCC in the esophagus.

Overexpression of cortactin increases invasion potential in oral squamous cell carcinoma

Cortactin, an F-actin binding protein, stabilizes F-actin networks and promotes actin polymerization by activating the Arp2/3 complex. Overexpression of cortactin has been reported in several human cancers. Cortactin stimulates cell migration, invasion, and experimental metastasis. However, the underlying mechanism is not still understood. In the present study, we therefore evaluated the possibility that cortactin could be appropriate as a molecular target for cancer gene therapy. In 70 primary oral squamous cell carcinomas and 10 normal oral mucosal specimens, cortactin expression was evaluated by immunological analyses, and the correlations of the overexpression of cortactin with clinicopathologic factors were evaluated. Overexpression of cortactin was detected in 32 of 70 oral squamous cell carcinomas; significantly more frequently than in normal oral mucosa. Cortactin overexpression was more frequent in higher grade cancers according to T classification, N classifications, and invasive pattern. Moreover, RNAi-mediated decrease in cortactin expression reduced invasion. Downregulation of cortactin expression increased the expression levels of E-cadherin, β-catenin, and EpCAM. The siRNA of cortactin also reduced PTHrP expression via EGF signaling. These results consistently indicate that the overexpression of cortactin is strongly associated with an aggressive phenotype of oral squamous cell carcinoma. In conclusion, we propose that cortactin could be a potential molecular target of gene therapy by RNAi targeting in oral squamous cell carcinoma.

Expression and prognostic value of MG7-Ag in patients with surgically resectable esophageal squamous cell carcinoma

PURPOSE

MG7-Ag is a human gastric-carcinoma-associated antigen. The expression of MG7-Ag was found to increase gradually with the development and progression of gastric cancer. Moreover, a poorer prognosis was found in MG7-Ag positive gastric-carcinoma patients than in MG7-Ag negative patients. However, neither MG7-Ag expression nor its clinical significance has been previously examined in squamous cell carcinoma (SCC) of the esophagus. In this study, we examined the expression of MG7-Ag in esophageal squamous cell carcinomas to assess its value as a prognostic indicator.

METHODS

The expression of MG7-Ag was detected in 112 cases of esophageal squamous cell carcinoma (SCC) by immunohistochemical analysis. The relation of MG7-Ag staining with various clinicopathological features was statistically analyzed.

RESULTS

The staining of MG7-Ag was detected in SCC, while not in normal epithelial cells. In esophageal SCC, MG7-Ag was found significantly correlated with depth of invasion (P = .012), in T4, T3 carcinomas but not in T2, T1 carcinomas, lymph node metastases (P = .029), pathological stage (P = .005). Consistently, the survival rate tended to be statistically lower in patients with MG7-Ag positive SCCs than in MG7-Ag negative SCCs (P = .005). However, no significant difference was observed between MG7-expression and patient age, sex, tumor location, differentiation, distant metastasis, and lymphatic invasion.

CONCLUSION

MG7-Ag might play a positive role in the process of carcinogenesis and progression of esophageal SCC, and it could be considered as one valuable prognostic indicator in esophageal SCC.

Amplification and overexpression of CTTN (EMS1) contribute to the metastasis of esophageal squamous cell carcinoma by promoting cell migration and anoikis resistance

Gain of chromosome 11q13 is a common event in esophageal squamous cell carcinoma (ESCC). The cortactin gene (CTTN, also EMS1), located at 11q13, plays a pivotal role in coupling membrane dynamics to cortical actin assembly. This gene has been implicated in the motility of several types of cells. In the present study, we found that the amplification and overexpression of the CTTN gene was associated with lymph node metastasis in ESCC. Functional analysis by small interfering RNA-mediated silencing of CTTN revealed that in addition to the effect on cell migration, CTTN influenced cell invasiveness by anoikis resistance. In vivo assay showed that inhibition of CTTN expression also decreased tumor growth and lung metastasis of ESCC cells. At the molecular level, we showed for the first time that the protective role of CTTN in anoikis resistance was correlated with the activation of the phosphatidylinositol 3-kinase/Akt pathway. Overall, the data suggest that CTTN is an oncogene in the 11q13 amplicon and exerts functions on tumor metastasis in ESCC.