MTA2 promotes the metastasis of esophageal squamous cell carcinoma via EIF4E-Twist feedback loop.

Metastasis-associated protein 2 (MTA2) is frequently amplified in many types of cancers; however, the role and underlying molecular mechanism of MTA2 in esophageal squamous cell carcinoma (ESCC) remain unknown. Here, we reported that MTA2 is highly expressed in ESCC tissue and cells, and is closely related to the malignant characteristics and poor prognosis of patients with ESCC. Through in vitro and in vivo experiments, we demonstrated that MTA2 significantly promoted ESCC growth, metastasis, and epithelial-mesenchymal transition (EMT) progression. This integrative analysis combined with expression microarray showed that MTA2 could interact with eukaryotic initiation factor 4E (EIF4E), which positively regulates the expression of Twist, known as a master regulator of EMT. Moreover, the results of chromatin immunoprecipitation revealed that MTA2 was recruited to the E-cadherin promoter by Twist, which reduced the acetylation level of the promoter region and thus inhibited expression of E-cadherin, and subsequently promoted the aggressive progression of ESCC. Collectively, our study provided novel evidence that MTA2 plays an aggressive role in ESCC metastasis by a novel EIF4E-Twist positive feedback loop, which may provide a potential therapeutic target for the management of ESCC.

p-Hydroxylcinnamaldehyde from cochinchinamomordica seed reverses resistance to TRAIL in human oesophageal squamous cell carcinoma via the activation of the p38 mitogen-activated protein kinase signalling pathway.

BACKGROUND: Our previous studies have showed that p-Hydroxylcinnamaldehyde (CMSP) could induce the differentiation of ESCC cells via the cAMP-RhoA-MAPK signalling pathway, which suggests a new potential strategy for ESCC treatment. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in several tumour cells by binding to the death receptors DR4 and DR5. However, TRAIL has little effect on oesophageal squamous cell carcinoma (ESCC) cells due to the loss of the receptors. The present study determined the effect of CMSP, the firstly found chemical constituent of Cochinchinamomordica seed (CMS), on TRAIL-induced apoptosis and its mechanism in ESCC cells. METHODS: MTS assays were performed to examine the CMSP- and TRAIL-mediated inhibition of ESCC cell growth. Flow cytometry and Hoechst 33258 staining assays were used to detect apoptosis in ESCC cells treated with CMSP combined with TRAIL. Western blotting was used to determine the effect of CMSP on the expression of p38, p-p38, DR4, DR5, Bid and caspase-3/8 in ESCC cells treated with CMSP combined with TRAIL. Additionally, immunodeficient Balb-c/null mouse model was used to determine the chemotherapeutic efficacy of CMSP and TRAIL against ESCC tumour xenograft growth in vivo. RESULTS: We found that the combination of CMSP and TRAIL had a greater inhibitory effect on ESCC cell viability in vitro than CMSP or TRAIL alone. CMSP enhanced the TRAIL-induced apoptosis in ESCC cells by upregulating the expression of DR4 and DR5 via the p38 MAPK signalling pathway. Furthermore, the increased expression of DR4 and DR5 upon TRAIL-induced apoptosis in ESCC cells was mediated at least in part by subsequent caspase-3 and caspase-8 activation. Moreover, the in vivo model showed that tumour growth was significantly slower in CMSP and TRAIL combination-treated mice than in mice treated with CMSP or TRAIL alone. CONCLUSION: Taken together, our findings indicate that CMSP as an extract from TCM, might be as a potential sensitizer of TRAIL and thus provide a novel strategy for the clinical treatment of ESCC.

The effect of polymorphisms in the promoter of the BIRC5 gene on the risk of oesophageal squamous cell carcinoma and patient's outcomes.

Baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5) is an inhibitor of apoptosis proteins and plays a key role in apoptosis or programmed cell death. In the present study, we evaluated the effect of BIRC5 gene polymorphisms on the risk of developing oesophageal squamous cell carcinoma (ESCC) and patients' outcomes in a high-incidence population from northern China. A population-based case-control study was performed in 597 ESCC patients and 597 control subjects.Survival data were available for 211 patients who received platinum-based chemotherapy after surgery. Five polymorphisms (-31 C>G, -241 C>T, -625 G>C, -644 T>C and -1547 A>G) in the promoter of the BIRC5 gene were genotyped by the polymerase chain reaction-ligase detection reaction (PCR-LDR) method. Compared with the -31 CC genotype, the -31 CG/GG genotype of -31 C>G single nucleotide polymorphism (SNP) was associated with a significant elevated risk of ESCC [adjusted odds ratio (OR) = 1.40, 95% confidence interval (CI) = 1.07-1.84]. Interestingly, this association was stronger among females, younger patients and non-smokers in stratified analyses (adjusted OR = 1.72, 95% CI = 1.07-2.75; adjusted OR = 1.61, 95% CI = 1.10-2.36; adjusted OR = 1.80, 95% CI = 1.26-2.58, respectively]. Survival analyses showed that the T allele of -241 C>T SNP was associated with poor prognosis [hazard ratio (HR) = 2.99, 95% CI = 1.09-8.19) and that the C allele of -625 G>C SNP was associated with good prognosis (HR = 0.62, 95% CI = 0.38-0.99) in ESCC patients. The -31 C>G polymorphism may be involved in the development of ESCC, and the -241 C>T and -625 G>C polymorphisms may be useful prognostic markers for ESCC.

Antitumor Effect of Periplocin in TRAIL-Resistant gastric cancer cells via upregulation of death receptor through activating ERK1/2-EGR1 pathway.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a member of the tumor necrosis factor family, induces apoptosis in a variety of cancer cells. However, gastric cancer (GC) cells are insensitive to TRAIL usually. In the previous study, we showed that Periplocin could induce apoptosis in GC cells via the activation of ERK1/2-EGR1 pathway. In the present study, we have shown that the combination of Periplocin and TRAIL had a greater inhibitory effect on gastric cancer cell viability in vitro and in vivo than Periplocin or TRAIL alone. Through upregulating the expression of DR4 and DR5 at transcriptional and protein levels, Periplocin enhanced the sensitivity of gastric cancer cells to TRAIL. Furthermore, enhanced activity of ERK1/2-EGR1 pathway was responsible for upregulating of DR4 and DR5 uponPeriplocin treatment, subsequently reducing the expression of Mcl-1 and Bcl2 and activating Bid and caspase-3/8. Collectively, these data implied that Periplocin might act as a sensitizer of TRAIL and could be a potential strategy for the treatment of GC.

The tumor-suppressive function of miR-1296-5p by targeting EGFR and CDK6 in gastric cancer.

We aimed to confirm the role of miR-1296-5p in gastric cancer and to identify its target genes. The expression of miR-1296-5p was measured in gastric cancer tissues and cell lines. The function of miR-1296-5p was examined by the overexpression and inhibition of its expression in typical gastric cell lines as well as SGC-7901 and MGC-803 cells. The targets of miR-1296-5p were identified by a luciferase activity assay. We found that miR-1296-5p was down-regulated in gastric cancer tissue and cell lines, and low expression levels of miR-1296-5p were associated with advanced clinical stage. Moreover, miR-1296-5p inhibited cell proliferation, migration, and invasion in SGC-7901 and MGC-803 cells. Then, we identified CDK6 and EGFR as novel targets of miR-1296-5p by a luciferase activity assay. Furthermore, the overexpression of miR-1296-5p suppressed the expression of CDK6 and EGFR. Our results indicated a tumor-suppressive role of miR-1296-5p through the translational repression of oncogenic CDK6 and EGFR in gastric cancer.

The histone deacetylase inhibitor panobinostat exerts anticancer effects on esophageal squamous cell carcinoma cells by inducing cell cycle arrest.

Esophageal squamous cell carcinoma (ESCC) is a common malignancy without effective therapy. Histone deacetylase inhibitors (HDACIs) have been demonstrated as an emerging class of anticancer drugs for a range of haematological and solid tumours. However, the effect of HDACIs has not yet been investigated on ESCC cells. In this study, HDACIs were initially considered to have anticancer activity for ESCC, due to the high expression of HDAC genes in ESCC cell lines by analysing expression data of 27 ESCC cell lines from the Broad-Novartis Cancer Cell Line Encyclopedia. Next, we used five ESCC cell lines and one normal immortalized esophageal epithelial cell line to screen three HDACIs, panobinostat (LBH589), vorinostat (SAHA), and trichostatin A (TSA), for the ability to inhibit growth. Here, we report that LBH589 more effectively suppressed cell proliferation of ESCC cell lines, in a dose-dependent manner, than TSA and SAHA, as well as had lower toxicity against the SHEE normal immortalized esophageal epithelial cell line. Further experiments indicated that LBH589 treatment significantly inhibited TP53 (mutated TP53) expression, both at the mRNA and protein level, and simultaneously increased p21 and decreased cyclin D1 expression. Taken together, we propose that LBH589 inhibits ESCC cell proliferation mainly through inducing cell cycle arrest by increasing p21 and decreasing cyclin D1 in a p53-independent manner. SIGNIFICANCE OF THE STUDY: In this study, the antitumor activity of HDACIs LBH589, SAHA, and TSA on ESCC was characterized, with LBH589 displaying the most potent anti-proliferative activity while not harming normal immortalized esophageal epithelial cells. Furthermore, we propose that LBH589 exerts its anti-proliferative effect by inducing cell cycle arrest. The ability to specifically target cancer cells indicates therapeutic potential for use of LBH589 in the treatment of ESCC.

B7­H3 promotes malignant progression of muscle­invasive bladder cancer.

The objective of the present study was to investigate the expression of B7 homologue 3 (B7­H3) in muscle­invasive bladder cancer (MIBC) tissues, evaluate its correlation with patient clinicopathological characteristics, and to explore the effect of B7­H3 on MIBC cells. B7­H3 expression levels in tumor tissues from 115 patients undergoing radical cystectomy for MIBC were detected by immunohistochemical staining, followed by analysis of the association with clinicopathological characteristics and survival. A B7­H3­silenced cell line was established by RNA interference (RNAi). Alterations in cell proliferation, cell cycle, migration and invasion were analyzed in vitro. The proteins associated with cancer cell behavior were detected by western blot analysis. In addition, we utilized a xenograft tumor assay in nude mice to test the inhibitory effect of B7­H3 shRNA on MIBC in vivo. The results revealed that, among the 115 patients, the B7­H3 expression level was significantly associated with an increased incidence of distant metastasis (P=0.014) and vascular invasion (P=0.031), whereas it was not statistically associated with sex, age, pathologic grade, tumor stage, recurrence and lymphatic metastasis. Overall survival (OS) and progression­free survival (PFS) were significantly worse for patients with high B7­H3 expression (P<0.001 and P<0.001, respectively) among the 115 MIBC patients. Suppression of B7­H3 significantly inhibited the proliferation, caused G2 phase arrest, as well as declined migration and invasion abilities in vitro. The protein expression of Ki67, proliferating cell nuclear antigen (PCNA), matrix metalloproteinase 2 (MMP2) and MMP9 were decreased in the T24/B7­H3 shRNA group compared with the control (P<0.05, respectively). Finally, we were able to inhibit tumor development by decreasing B7­H3 expression in vivo. In conclusion, a high expression level of B7­H3 in MIBC tissues is associated with a poor clinicopathological status and poor prognosis, and promotes the development of MIBC in vitro and in vivo. Thus, B7­H3 may be a potential novel biomarker for the poor prognosis of MIBC patients.

Risk factors for pulmonary nodules in north China: A prospective cohort study.

OBJECTIVES: Pulmonary nodules have become common incidental findings with the widespread use of computed tomography (CT) technology. Such nodules have the potential to become early lung cancer lesions, so understanding more about factors that may be associated with them is important. MATERIALS AND METHODS: The present work was based on a large prospective cohort comprising 32,438 participants in Hebei Province (China) between January 2014 and March 2016. Participants aged 40-75 years completed a questionnaire, underwent low-dose CT (LDCT), and were followed up to March 2017. Grouped by the results of LDCT, normal participants and those with pulmonary nodules were included in the data analysis. RESULTS: In total 7752 subjects were included in this study, of whom 2040 (26.32%) were pulmonary nodule patients. Older age, current smoking status (hazard ratio (HR) = 1.43, 95% confidence interval (95%CI): 1.21, 1.68), exposure to second-hand smoke (SHS) at work (HR = 1.17, 95%CI: 1.01, 1.35), dust exposure (HR = 1.49, 95%CI: 1.06, 2.11), history of lung disease (HR = 1.44, 95%CI: 1.16, 1.77), and family history of cancer (HR = 1.28, 95%CI: 1.12, 1.48) were associated with pulmonary nodules. However, consumption of vegetables (HR = 0.82, 95%CI: 0.68, 0.99), tea (HR = 0.88, 95%CI: 0.78, 0.99) and legumes reduced the risk. Approximately 10.09% and 8.58% of pulmonary nodule incidences were attributed to tobacco smoking and low fruit intake, respectively. An estimated 6.36% and 3.88% of patients with pulmonary nodules attributable to family history of cancer and history of lung disease were detected. CONCLUSION: The results of this study suggest that age, smoking, SHS, dietary factors, occupational exposures, history of disease and family history of cancer may affect the incidence of pulmonary nodules.

C/D-Box Snord105b Promotes Tumorigenesis in Gastric Cancer via ALDOA/C-Myc Pathway.

BACKGROUND/AIMS: Small nucleolar RNAs (snoRNAs) play an important role in carcinogenesis. In this study, we identified a C/D box snoRNA, snord105b, and further investigated the function and mechanism of the snord105b in gastric cancer (GC). METHODS: The expression level of snord105b in GC tissures, sera and cell lines were detected by qRT-PCR. Cell viability was assessed using MTS assay. Transwell and wound healing assay were performed to evaluate migration and invasion, and protein expression was examined by western blotting. ChIRP and MS analysis was used to seek for the special binding protein of snord105b. RESULTS: The snord105b was upregulated and associated with tumor size, differentiation, and pathological stage in GC. Snord105b affected proliferation, migration and invasion in multiple GC cell lines. The oncoqenic activity of snord105b was also confirmed with in vivo data. Mechanistically, snord105b specifically bound to ALDOA and affected C-myc, which plays a key role in carcinogenesis and tumor development. CONCLUSION: Snord105b appears to be a novel oncogene and is clinically and functionally involved in the development of GC. Targeting snord105b and its pathway may provide new biomarkers or potential treatments for patients with GC.

All-trans retinoic acid enhances cytotoxicity of CIK cells against human lung adenocarcinoma by upregulating MICA and IL-2 secretion.

To determine the growth inhibition capability of all-trans retinoic acid (ATRA) with cytokine-induced killer cells (CIKs), we evaluated their effects, alone and in combination, on human lung carcinoma A549 cells. CIKs treated with ATRA significantly inhibited cell growth. Additionally, CIK with ATRA synergistically inhibited migration and invasiveness, colony formation of A549 and NCI-H520 cells. Furthermore, analysis of apoptosis markers Bcl-2, Bax, Survivin and cleaved Caspase-3 showed that Bcl-2 and Survivin mRNA levels significantly decreased, and that Bax mRNA significantly increased, in the CIK + ATRA-treated cells, with corresponding effects on their respective proteins. The involved mechanisms may be associated with upregulated expression of MHC class I-Related Chain (MICA) and interleukin (IL)-2. These results suggest that administration of combined CIK and ATRA is a potentially novel treatment for lung carcinoma.

Programmed death-1 ligand-1 gene rs2890658 polymorphism associated with the risk of esophageal squamous cell carcinoma in smokers.

BACKGROUND: The most important anti-tumor immune response is mediated by T lymphocytes. The interaction of programmed death-1 ligand-1 (PD-L1) with its receptor provides an inhibitory signal in T lymphocytes activation and proliferation. OBJECTIVE: This study aimed to investigate whether polymorphisms of PD-L1 were associated with the risk and prognosis of esophageal squamous cell carcinoma (ESCC) in a high-incidence population from Northern China. METHODS: PD-L1 rs2890658 A/C and rs4143815 C/G single nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction ligase detection reaction (PCR-LDR) method in 575 ESCC patients and 577 healthy controls. RESULTS: There was no significant difference in the genotype frequencies of these two SNPs between the ESCC patients and the healthy controls. However, for rs2890658 A/C SNP, compared with the C/C genotype, the A/C genotype increased the risk of ESCC for the smokers (OR = 1.513, 95% CI = 1.006-2.287). Among the 575 ESCC patients, the survival information of 202 ESCC patients was collected. Neither the rs2890658 A/C SNP nor the rs4143815 C/G SNP was associated with the survival of ESCC patients. CONCLUSIONS: PD-L1 rs2890658 A/C SNP might be used as risk marker of the susceptibility to ESCC for the Han nationality in a high-incidence population from Northern China.

Aberrant methylation of DACT1 and DACT2 are associated with tumor progression and poor prognosis in esophageal squamous cell carcinoma.

BACKGROUND: The DACT (Dishevelled-associated antagonist of ß-catenin) family of scaffold proteins may play important roles in tumorigenesis. However, the epigenetic changes of DACT1, 2, 3 and their effect on esophageal squamous cell carcinoma (ESCC) have not been investigated so far. The aim of this study was to investigate the promoter methylation and expression of DACT family, in order to elucidate more information on the role of DACT with regard to the progression and prognosis of ESCC. METHODS: MSP and BGS methods were respectively applied to examine the methylation status of DACT; RT-PCR, Western blot and immunohistochemistry methods were respectively used to determine the mRNA and protein expression of DACT; MTT, Colony-formation and Wound-healing assay were performed to assess the effect of DACT1 and DACT2 on proliferation and migration of esophageal cancer cells. RESULTS: Frequent reduced expression of DACT1, DACT2 and DACT3 were found in esophageal cancer cell lines and the expression levels of DACT1 and DACT2 were reversed by 5-Aza-Dc. Decreased mRNA and protein expression of DACT1 and DACT2 were observed in ESCC tumor tissues and were associated with the methylation status of transcription start site (TSS) region. The hypermethylation of CpG islands (CGI) shore region in DACT1 was observed both in tumor and corresponding adjacent tissues but wasn't related to the transcriptional inhibition of DACT1. The methylation status of TSS region in DACT1 and DACT2 and the protein expression of DACT2 were independently associated with ESCC patients' prognosis. CONCLUSIONS: The TSS region hypermethylation may be one of the main mechanisms for reduced expression of DACT1 and DACT2 in ESCC. The simultaneous methylation of DACT1 and DACT2 may play important roles in progression of ESCC and may serve as prognostic methylation biomarkers for ESCC patients.

A novel curcumin analogue is a potent chemotherapy candidate for human hepatocellular carcinoma.

Curcumin (CUR) has been demonstrated to protect against carcinogenesis and to prevent tumor development in cancer; however, the clinical application of CUR is limited by its instability and poor metabolic properties. The present study offers an strategy for a novel CUR analogue, (1E,4E)-1,5-bis(2-bromophenyl)penta-1,4-dien-3-one (GL63), to be used as a potential therapeutic agent for hepatocellular carcinoma (HCC) in vitro and in vivo. The current study demonstrated that GL63 exhibited more potent inhibition of proliferation of HCC cells than CUR. GL63 induced G0/G1 phase cell cycle arrest and apoptosis in SK-HEP-1 cells in a dose-dependent manner, and was more potent than CUR, according to the flow cytometry data. The present study demonstrated for the first time that the inhibition of the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway by GL63 resulted in a protective effect against HCC cell growth. GL63 was more effective than CUR in regulating STAT3 downstream targets, which contributed to the suppression of cell proliferation and the induction of cell apoptosis. In addition, the effects of GL63 were tested in a model of N-nitrosodiethylamine (DEN)-induced HCC in Wistar rats. Although macroscopic and microscopic features suggested that both GL63 and CUR were effective in inhibiting DEN-induced hepatocarcinogenesis, GL63 exerted a stronger effect than CUR. Immunohistochemical analysis for proliferating cell nuclear antigen demonstrated significant differences among the DEN-bearing non-treated, DEN-bearing GL63-treated and DEN-bearing, CUR-treated groups (P=0.039). It was concluded that GL63 was a potent agent able to suppress the proliferation of HCC cells by inhibition of the JAK2/STAT3 signaling pathway, with more favorable pharmacological activity than CUR, and may be a more potent compound for the prevention of DEN-induced hepatocarcinogenesis in rats than CUR.

Association of programmed death-1 polymorphisms with the risk and prognosis of esophageal squamous cell carcinoma.

Programmed death-1 (PD-1) is an immunoinhibitory receptor belonging to the CD28 family. This study was designed to investigate the association of PD-1 rs36084323:A>G, rs2227981:C>T, rs2227982:C>T and rs10204525:A>G single nucleotide polymorphisms (SNPs) with the risk and prognosis of esophageal squamous cell carcinoma (ESCC) in a high-incidence population from Northern China. These four SNPs were genotyped by polymerase chain reaction ligase detection reaction (PCR-LDR) method in 584 ESCC patients and 585 healthy controls. The rs2227981:C>T SNP C/T genotype increased the risk of ESCC for the smokers (OR = 1.483, 95% CI = 1.018-2.160) and rs2227982:C>T SNP C/T genotype enhanced susceptibility to ESCC for the females (OR = 1.708, 95% CI = 1.056-2.762). For rs10204525:A>G SNP, A/A genotype was related to increased risk of ESCC (OR = 1.735, 95% CI = 1.086-2.771) overall. Among the 584 ESCC patients, the survival information of 204 ESCC patients was collected. The rs36084323:A>G SNP A/G genotype was associated with lower risk of death in ESCC patients with upper gastrointestinal cancer (UGIC) family history (HR = 0.339, 95%CI = 0.115-0.996). The rs2227982:C>T SNP C/T genotype was associated with lower risk of death in smoker ESCC patients and ESCC patients with UGIC family history (HR = 0.409 and 0.292, 95%CI = 0.194-0.863 and 0.101-0.847). PD-1 rs2227981:C>T, rs2227982:C>T and rs10204525:A>G SNPs might be used as predictive markers of the susceptibility to ESCC for the Han nationality in a high-incidence population from Northern China. PD-1 rs36084323:A>G and rs2227982:C>T SNPs were associated with the prognosis of the Han ESCC patients in this high-incidence region.

The tumor suppressor miR-124 inhibits cell proliferation and invasion by targeting B7-H3 in osteosarcoma.

Our previous studies have shown that the expression level of B7 homolog 3 (B7-H3) was correlated with clinical staging and prognosis of osteosarcoma (OS) patients, and its silencing inhibited the proliferation and invasion of OS cells in vitro. However, its overexpression mechanism behind was far from elucidated. On the basis of bioinformatics and the preliminary screening data, we hypothesized that miR-124 might play an important role in OS development and as a lead candidate for modulating B7-H3 expression. In this study, we found that miR-124 was downregulated significantly in OS tumor tissue, compared to normal adjacent tissues (NATs). Lower miR-124 expression levels were associated with advanced Ennecking stage, lower tumor differentiation, and common pulmonary metastasis. The 5-year overall survival rate in the miR-124 upregulated group was 61.5 %, while with low miR-124 expression, only 11.8 % survived. Further studies in vitro showed that B7-H3 was a direct target of miR-124. Overexpression of miR-124 decreased B7-H3 mRNA and protein level and inhibited B7-H3 3'-UTR reporter activity. Treatment of OS cells with miR-124 mimics induced the inhibition of cell growth and invasion in vitro, which could be abrogated by transfected by B7-H3 expression vector. Our findings highlight the potential application of miR-124 as a novel onco-miRNA in OS, and its oncogenic effects are mediated chiefly through downregulation of B7-H3, thus suggesting a model for identifying miR-124 that can be exploited to improve the therapeutic potential efficacy of mAb targeting to B7-H3.

p-Hydroxylcinnamaldehyde induces the differentiation of oesophageal carcinoma cells via the cAMP-RhoA-MAPK signalling pathway.

p-Hydroxylcinnamaldehyde (CMSP) has been identified as an inhibitor of the growth of various cancer cells. However, its function in oesophageal squamous cell carcinoma (ESCC) and the underlying mechanism remain unclear. The aim of the present study was to characterize the differentiation effects of CMSP, as well as its mechanism in the differentiation of ESCC Kyse30 and TE-13 cells. The function of CMSP in the viability, colony formation, migration and invasion of Kyse30 and TE-13 cells was determined by MTS, colony-formation, wound healing and transwell assays. Western blotting and pull-down assays were used to investigate the effect of CMSP on the expression level of malignant markers of ESCC, as well as the activity of MAPKs, RhoA and GTP-RhoA in Kyse30 and TE-13 cells. We found that CMSP could inhibit proliferation and migration and induce Kyse30 and TE-13 cell differentiation, characterized by dendrite-like outgrowth, decreased expression of tumour-associated antigens, as well as the decreased expression of malignant markers. Furthermore, increased cAMP, p-P38 and decreased activities of ERK, JNK and GTP-RhoA, were detected after treatment with CMSP. These results indicated that CMSP induced the differentiation of Kyse30 and TE-13 cells through mediating the cAMP-RhoA-MAPK axis, which might provide new potential strategies for ESCC treatment.

P-Hydroxycinnamaldehyde Induces B16-F1 Melanoma Cell Differentiation via the RhoA-MAPK Signaling Pathway.

BACKGROUND/AIMS: Due to its antitumor and gastroprotective properties, cochinchina momordica seed (CMS), has been widely used to treat cancer patients in Asia. Our previous reports have shown that CMS is able to induce the differentiation of B16-F1 melanoma cells. However, its functional component and mechanism remain unclear and are addressed in this study. METHODS AND RESULTS: CMSP (p-hydroxycinnamaldehyde isolated from CMS) inhibited the proliferation, migration and invasiveness of B16-F1 cells both in vivo and in vitro. CMSP also induced the differentiation of B16-F1 cells, as characterized by dendrite-like outgrowth, increased melanogenesis and enhanced tyrosinase activity. Furthermore, CMSP treatment reduced the level of malignant markers of melanoma, specifically S-100B and melanoma-derived growth regulatory protein precursor (MIA), in a concentration-dependent manner. According to a western blot analysis, B16-F1 cells treated with CMSP exhibited a sustained increase in p-P38 and decreased activities of ERK and JNK. Our data further indicated that the downregulation of GTP-RhoA, which was mediated by increased cAMP release, was involved in CMSP-induced changes in MAPK, while LPA (Lysophosphatidic acid) partially reversed CMSP-induced B16 cell differentiation. CONCLUSION: These results demonstrated that CMSP-induced differentiation of B16F1 cells may occur through the RhoA-MAPK axis, which suggests a new potential strategy for melanoma treatment.

Periplocin Extracted from Cortex Periplocae Induced Apoptosis of Gastric Cancer Cells via the ERK1/2-EGR1 Pathway.

BACKGROUND/AIMS: Periplocin is extracted from the traditional herbal medicine cortex periplocae, which has been reported to suppress the growth of cancer cells. However, little is known about its effect on gastric cancer cells. METHODS: Gastric cancer cells were treated with periplocin, and cell viability was assessed using MTS assay. Flow cytometry and TUNEL staining were performed to evaluate apoptosis, and protein expression was examined by western blotting. Microarray analysis was used to screen for changes in related genes. RESULTS: We found that periplocin had an inhibitory effect on gastric cancer cell viability in a dose-dependent manner. Periplocin inhibited cell viability via the ERK1/2-EGR1 pathway to induce apoptosis. Periplocin also inhibited the growth of tumor xenografts and induced apoptosis in vivo. CONCLUSION: Our results show that periplocin inhibits the proliferation of gastric cancer cells and induces apoptosis in vitro and in vivo, indicating its potential to be used as an antitumor drug.

Biomarkers for EMT and MET in breast cancer: An update.

Metastasis and recurrence are the leading cause of mortality due to breast cancer, but the underlying mechanisms are still poorly understood. Understanding the breast cancer metastasis mechanism is important for early diagnosis and treatment of breast cancer. The seeding and growth of breast cancer cells at sites distinct from the primary tumor is a complex and multistage process. Recently, it has been reported that the epithelial-mesenchymal transition (EMT) and the mesenchymal-epithelial transition (MET) are the main mechanisms for breast cancer metastasis. During EMT, carcinoma cells shed their differentiated epithelial characteristics, including cell-cell adhesion, polarity and lack of motility, and acquire mesenchymal traits, including motility and invasiveness. This review has summarized the studies of known EMT biomarkers in the context of breast cancer progression. These biomarkers include EMT-related genes, proteins, microRNAs and kinases. In general, the findings of these studies suggest that EMT markers are associated with the invasion and metastasis of breast cancer. Further studies on the link between EMT markers and breast cancer will contribute to identify biomarkers for predicting early breast cancer metastasis as well as to provide new ideas for the treatment of breast cancer.

Roles of coinhibitory molecules B7-H3 and B7-H4 in esophageal squamous cell carcinoma.

The coinhibitory molecules, B7-H3 and B7-H4, have shown negative regulation in T cell activation and tumor-associated macrophage (TAM) polarization in tumor-specific immunity. Here, we investigated the expression of B7-H3 and B7-H4 in human and murine esophageal squamous cell carcinoma (ESCC) tissues to define their clinical significance and mechanism in a tumor microenvironment. In the present study, B7-H3 and B7-H4 were expressed in 90.6 and 92.7 % samples, respectively. High B7-H3 and B7-H4 expression was associated with advanced TNM stage and lymph node metastasis (p < 0.05, respectively). Patients with both B7-H3 and B7-H4 high-expressed tumors had the poorest prognosis (26.7 months), whereas those with both low-expressed tumors had the best survival (56.7 months). B7-H3 and B7-H4 expression were inclined to be positively related to the infiltration intensity of Treg cells and TAMs (p < 0.05, respectively), and B7-H3 expression is negatively associated with the intensity of CD8(+) T cells (p < 0.05). In 4-nitroquinoline 1-oxide (4-NQO)-induced murine models, high B7-H3 expression could only be detected at carcinoma stage, but abnormal B7-H4 expression appeared a little earlier at dysplasia stage. In vitro studies revealed that knockdown of B7-H3 on tumor cells suppressed ESCC cell migration and invasion, while knockdown of B7-H4 could inhibit ESCC cell growth. Overall, B7-H3 and B7-H4 are involved in ESCC progression and development and their coexpression could be valuable prognostic indicators. Interference of these negative regulatory molecules might be a new strategy for treating ESCC.