The prognostic value of a seven-lncRNA signature in patients with esophageal squamous cell carcinoma: a lncRNA expression analysis.

BACKGROUND: Long non-coding RNAs (lncRNAs) have been reported to be prognostic biomarkers in many types of cancer. We aimed to identify a lncRNA signature that can predict the prognosis in patients with esophageal squamous cell carcinoma (ESCC). METHODS: Using a custom microarray, we retrospectively analyzed lncRNA expression profiles in 141 samples of ESCC and 81 paired non-cancer specimens from Sun Yat-Sen University Cancer Center (Guangzhou, China), which were used as a training cohort to identify a signature associated with clinical outcomes. Then we conducted quantitative RT-PCR in another 103 samples of ESCC from the same cancer center as an independent cohort to verify the signature. RESULTS: Microarray analysis showed that there were 338 lncRNAs significantly differentially expressed between ESCC and non-cancer esophagus tissues in the training cohort. From these differentially expressed lncRNAs, we found 16 lncRNAs associated with overall survival (OS) of ESCC patients using Cox regression analysis. Then a 7-lncRNA signature for predicting survival was identified from the 16 lncRNAs, which classified ESCC patients into high-risk and low-risk groups. Patients with high-risk have shorter OS (HR: 3.555, 95% CI 2.195-5.757, p < 0.001) and disease-free survival (DFS) (HR: 2.537, 95% CI 1.646-3.909, p < 0.001) when compared with patients with low-risk in the training cohort. In the independent cohort, the 7 lncRNAs were detected by qRT-PCR and used to compute risk score for the patients. The result indicates that patients with high risk also have significantly worse OS (HR = 2.662, 95% CI 1.588-4.464, p < 0.001) and DFS (HR 2.389, 95% CI 1.447-3.946, p < 0.001). The univariate and multivariate Cox regression analyses indicate that the signature is an independent factor for predicting survival of patients with ESCC. Combination of the signature and TNM staging was more powerful in predicting OS than TNM staging alone in both the training (AUC: 0.772 vs 0.681, p = 0.002) and independent cohorts (AUC: 0.772 vs 0.660, p = 0.003). CONCLUSIONS: The 7-lncRNA signature is a potential prognostic biomarker in patients with ESCC and may help in treatment decision when combined with the TNM staging system.

Cx43 Inhibition Attenuates Sepsis-Induced Intestinal Injury via Downregulating ROS Transfer and the Activation of the JNK1/Sirt1/FoxO3a Signaling Pathway.

Intestinal injury has long been considered to play a crucial role in the pathophysiology of sepsis and has even been characterized as the "motor" of it. Thus, we explored the effects of connexin43 (Cx43) on sepsis-induced intestinal injury in order to provide potential therapeutic strategies. Rat cecal ligation and puncture (CLP) models in vivo and cell models (IEC-6 cells) pretreated with LPS in vitro were used in the current study. Firstly, different methods, such as Cx43 inhibitors (18-α-GA and oleamide) or siRNA targeting Cx43 and N-acetyl cysteine (NAC) (a kind of ROS scavenger), were used to observe the effects of Cx43 channels mediating ROS transfer on intestinal injury. Secondly, the influence of ROS content on the activity of the JNK1/Sirt1/FoxO3a signaling pathway was explored through the application of NAC, sp600125 (a JNK1 inhibitor), and nicotinamide (a Sirt1 inhibitor). Finally, luciferase assays and ChIP were used to determine the direct regulation of FoxO3a on proapoptotic proteins, Bim and Puma. The results showed that sepsis-induced intestinal injury presented a dynamic change, coincident with the alternation of Cx43 expression. The inhibition of Cx43 attenuated CLP-induced intestinal injury in vivo and LPS-induced IEC-6 injury in vitro. The changes of Cx43 channel function regulated ROS transfer between the neighboring cells, which mediated the activation of the JNK1/Sirt1/FoxO3a signaling pathway. FoxO3a directly affected its downstream target genes, Bim and Puma, which are responsible for cell or tissue apoptosis. In summary, our results suggest that Cx43 inhibition suppresses ROS transfer and inactivates the JNK1/Sirt1/FoxO3a signaling pathway to protect against sepsis-induced intestinal injury.

LINC01133 as ceRNA inhibits gastric cancer progression by sponging miR-106a-3p to regulate APC expression and the Wnt/ß-catenin pathway.

BACKGROUND: Gastric cancer (GC) is a common malignancy and frequent cause of cancer-related death. Long non-coding RNAs (lncRNAs) have emerged as important regulators and tissue-specific biomarkers of multiple cancers, including GC. Recent evidence has indicated that the novel lncRNA LINC01133 plays an important role in cancer progression and metastasis. However, its function and molecular mechanism in GC remain largely unknown. METHODS: LINC01133 expression was detected in 200 GC and matched non-cancerous tissues by quantitative reverse transcription PCR. Gain- and loss-of-function experiments were conducted to investigate the biological functions of LINC01133 both in vitro and in vivo. Insights into the underlying mechanisms of competitive endogenous RNAs (ceRNAs) were determined by bioinformatics analysis, dual-luciferase reporter assays, quantitative PCR arrays, TOPFlash/FOPFlash reporter assay, luciferase assay, and rescue experiments. RESULTS: LINC01133 was downregulated in GC tissues and cell lines, and its low expression positively correlated with GC progression and metastasis. Functionally, LINC01133 depletion promoted cell proliferation, migration, and the epithelial-mesenchymal transition (EMT) in GC cells, whereas LINC01133 overexpression resulted in the opposite effects both in vitro and in vivo. Bioinformatics analysis and luciferase assays revealed that miR-106a-3p was a direct target of LINC01133, which functioned as a ceRNA in regulating GC metastasis. Mechanistic analysis demonstrated that miR-106a-3p specifically targeted the adenomatous polyposis coli (APC) gene, and LINC01133/miR-106a-3p suppressed the EMT and metastasis by inactivating the Wnt/ß-catenin pathway in an APC-dependent manner. CONCLUSIONS: Our findings suggest that reduced expression of LINC01133 is associated with aggressive tumor phenotypes and poor patient outcomes in GC. LINC01133 inhibits GC progression and metastasis by acting as a ceRNA for miR-106a-3p to regulate APC expression and the Wnt/ß-catenin pathway, suggesting that LINC01133 may serve as a potential prognostic biomarker and anti-metastatic therapeutic target for GC.

Predictive Value of LINC01133 for Unfavorable Prognosis was Impacted by Alcohol in Esophageal Squamous Cell Carcinoma.

BACKGROUND/AIMS: Considerable evidence indicates that long noncoding RNAs (lncRNAs) exert importantly regulatory functions during human cancer initiation and progression and are promising biotargets in the flight against cancer. METHODS: In this study, we evaluated the role of the lncRNA LINC01133 in esophageal squamous cell carcinoma (ESCC). LINC01133 expression in ESCC was examined by quantitative real-time PCR. The correlations between LINC01133 expression and clinicopathological variables and survival were examined by the χ2 test, Kaplan-Meier method, log-rank test, and univariate Cox regression analysis. RESULTS: LINC01133 expression levels were frequently lower in ESCC tissues and cell lines than in paired normal tissues and an immortalized esophageal epithelial cell line, respectively. The expression of LINC01133 decreased in a TNM stage- and lifestyle-independent manner. LINC01133 was an independent protective factor and had an anti-tumor effect in the early stage of ESCC development. More importantly, we discovered that drinking status in our cohort impaired the predictive accuracy of LINC01133 for patients with ESCC. Furthermore, a new risk model combining LINC01133 expression, drinking status, and TNM stage provided better survival discrimination compared with three other predictors. CONCLUSIONS: Our data indicate that a loss of LINC01133 expression is a potential poor prognostic biomarker and therapeutic target for ESCC and provide additional prognostic information to improve the outcomes of ESCC patients.

Long Non-Coding RNA XLOC_006753 Promotes the Development of Multidrug Resistance in Gastric Cancer Cells Through the PI3K/AKT/mTOR Signaling Pathway.

BACKGROUND/AIMS: The development of multidrug resistance (MDR), which results in disease recurrence and metastasis, is a crucial obstacle to successful chemotherapy for patients with gastric cancer (GC). Long non-coding RNAs (lncRNAs) have been found to play various roles in cancer. This study aimed to investigate the effect of XLOC_006753 on the development of MDR in GC cells. METHODS: The expression levels of XLOC_006753 in GC patients and MDR GC cell lines (SGC-7901/5-FU and SGC-7901/DDP cell line) were assessed by qRT-PCR. Statistical analyses were conducted to determine the relationship between XLOC_006753 expression and clinical features and to assess the prognostic value of XLOC_006753 for overall survival and progression-free survival. Then, a CCK-8 assay was used to detect cell proliferation ability and chemosensitivity. Flow cytometry was used to detect cell cycle and cell apoptosis. A wound-healing assay and transwell assay were used to detect cell migration. The expression of markers for MDR, G1/S transition, epithelial-mesenchymal transition (EMT) and PI3K/ AKT/mTOR signaling pathway were examined by western blot. RESULTS: XLOC_006753 was highly expressed in GC patients and MDR GC cell lines (SGC-7901/5-FU and SGC-7901/DDP cell lines), and its high expression was positively associated with metastasis, TNM stage, tumor size, and poor survival in GC patients. Moreover, XLOC_006753 was an independent prognostic biomarker of overall survival and progression-free survival for gastric cancer patients. Knocking down XLOC_006753 in the two MDR GC cell lines significantly inhibited cell proliferation, cell viability, cell cycle G1/S transition, and migration. XLOC_006753 knockdown also promoted apoptosis. Furthermore, western blots showed that XLOC_006753 knockdown decreased some markers of MDR, G1/S transition, and EMT expression, while increasing caspase9 expression and inhibiting the PI3K/AKT/mTOR signaling pathway in SGC-7901/5-FU and SGC-7901/DDP cells. CONCLUSION: High expression of XLOC_006753 promoted the development of MDR, which was activated by the PI3K/AKT/mTOR pathway in GC cells.

Increased expression of LINC00323 correlates with tumor progression and poor prognosis of gastric cancer.

BACKGROUD/AIMS: LINC00323 is a novel lncRNA which has reported to play an important role in the development and recurrence in several cancers. However, the expression and predictive value of LINC00323 in gastric cancer (GC) remain mysterious. METHODS: LINC00323 expression in GC tissues and adjacent normal tissues was evaluated by quantitative reverse-transcription PCR (qRT-PCR). The relationship between LINC00323 expression and clinicopathological features and patients' survival were analyzed. Univariate and multivariate survival analyses were performed. RESULTS: LINC00323 expression were found to be significantly increased in GC tissues. High expression of LINC00323 exerted a pro-tumor effect in the late stage of GC development. Kaplan-Meier analysis showed that patients with high LINC00323 were associated with poor overall survival (OS) and progression-free survival (PFS). Moreover, the combination of TNM stage and drinking status better identified GC patient outcome than those of TNM stage alone. CONCLUSIONS: Our data showed that LINC00323 overexpression might serve as a novel independent prognostic factor for survival of GC patients, suggesting LINC00323 was a potential biomarker and therapeutic target for GC.

Noncoding RNAs and hyperthermic intraperitoneal chemotherapy in advanced gastric cancer.

Gastric cancer (GC) is one of the most common malignant tumors globally. About 20-30% of patients with gastric cancer show peritoneal implantation metastasis at the first diagnosis. Peritoneal metastasis is responsible for 70% of deaths of patients with advanced gastric cancer. Although there are many ways to treat advanced gastric cancer, the prognosis of patients with recurrence is unsatisfactory. An auxiliary treatment with hyperthermic intraperitoneal chemotherapy (HIPEC), is an internationally recognized recommended treatment for advanced gastric cancer. A series of clinical trials have shown that HIPEC significantly improves the overall survival of patients with cancer. Compared with the cytoreductive surgery (CRS) alone, HIPEC combined with CRS markedly reduced the rate of peritoneal metastasis in patients with ovarian cancer and colorectal cancer. It has been demonstrated that HIPEC alters transcription of many genes by affecting non-coding RNAs, which may contribute to the suppressive effect of HIPEC on the synthesis of nucleic acids and proteins in cancer cells. This paper reviews the recent advances in understanding the role of non-coding RNAs in tumor invasion and metastasis of advanced gastric cancer. We also consider changes in noncoding RNA levels and other molecules in advanced gastric cancer cases treated with HIPEC. We hope that our review will provide a reference for future research on molecular epidemiology and etiology of advanced gastric cancer and promote precise treatment of this malignancy using HIPEC.

Construction of a competing endogenous RNA network and identification of potential regulatory axes in gastric cancer chemoresistance.

BACKGROUND: Emerging evidence highlights the multifunctional role of noncoding RNAs (ncRNAs) in gastric cancer (GC) chemoresistance. However, the comprehensive expression profile and competing endogenous RNAs (ceRNAs) regulatory network of GC chemoresistance remain unanswered. METHODS: The whole-transcriptome sequencing (RNA sequencing) was performed to comprehensively analyze the differentially expressed (DE) lncRNAs, miRNAs and mRNAs in cisplatin-resistant cells MGC-803/DDP and GC cells MGC-803. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted to investigate the biological functions implicated with the DEncRNAs. Then, the cisplatin-resistant-related ceRNA network and potential regulatory axes were constructed by bioinformatic analysis. RESULTS: We successfully generated cisplatin-resistant GC cell line MGC-803/DDP. Differential expression analysis showed that a total of 1936 DElncRNAs, 2194 DEmRNAs and 174 DEmiRNAs were identified. Functional enrichment analysis indicated that those DEncRNAs were mainly involved in neuroactive ligand-receptor interaction, drug metabolism and Hippo signaling pathway. Subsequently, the cisplatin-resistant-related ceRNA network was constructed with the widely accepted vital chemo-resistant-related genes and signaling pathways. In addition, two constructed regulatory axes (include FAM66C/miR-129-5p/7 mRNAs and SFTA1P/miR-206/FN1 or NRP1) were successfully validated by the Genomic Data Commons (GDC) GC data. CONCLUSIONS: The novel ceRNA network and the potential regulatory axes may provide the most comprehensive view of GC chemoresistance to date. Our findings uncovered potential biomarkers for prognostic prediction and novel therapeutic targets for reversing cisplatin resistance in GC.

A somatic mutation-derived LncRNA signatures of genomic instability predicts the prognosis and tumor microenvironment immune characters in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is an aggressive carcinoma with genome instability. Long non-coding RNAs (LncRNAs) have been functionally associated with genomic instability in cancers. However, the identification and prognostic value of lncRNAs related to genome instability have not been explored in hepatocellular carcinoma. In this study, we aim to identify a genomic instability-related lncRNA signature for predicting prognosis and the efficacy of immunotherapy in HCC patients. METHODS: According to the somatic mutation and transcript data of 364 patients with HCC, we determined differentially expressed genome instability-related lncRNAs (GInLncRNAs). Gene ontology (GO) enrichment analyses and Kyoto Encyclopedia of genes and genomes enrichment analyses revealed the potential functions of genes co-expressed with those lncRNAs involved in cancer development and immune function. We further determined a genome instability-related lncRNA signature (GInLncSig) through Cox regression analysis and LASSO regression analysis. Thereafter, we performed correlation analyses with mutations, clinical stratification analyses, and survival analyses to evaluate GInLncSig predictive function. Subsequently, we construct a nomogram model for prognostic assessments of patients with HCC. Finally, we performed Immunocytes infiltration analysis, gene set enrichment analysis (ssGSEA) of immunity circle-associated pathways, and T cell-inflamed score to explore GInLncSig's potential value in guiding immunotherapy. RESULTS: We identified 11 independent prognosis-associated GInLncRNAs (AC002511.2, LINC00501, LINC02055, LINC02714, LINC01508, LOC105371967, RP11_96A15.1, RP11_305F18.1, RP11_342M1.3, RP11_432J24.3, U95743.1) to construct a GInLncSig. According to the risk score calculated by GInLncSig, the high-risk group was characterized by a higher somatic mutation count, significantly poorer clinical prognosis, higher T cell-inflamed score, and specific tumor immune infiltration status compared to the low-risk group. Furthermore, we constructed a nomogram model to improve the reliability and clinical utility of predicting the prognosis of patients with HCC. CONCLUSION: Our study established a reliable prognostic prediction signature that could be a tool for prognosis prediction and a promising predictive biomarker of immunotherapy in hepatocellular carcinoma.

High miR-3650 expression in nasopharyngeal carcinoma and its clinical prognostic values.

BACKGROUND: A recent study has reported that miR-3650 expression was significant reduced in hepatocellular carcinoma and predicted poor prognosis. However, the role of miR-3650 in nasopharyngeal carcinoma (NPC) remains indefinite. METHODS: Total 140 cases of NPCs were included in this study. The expression of miR-3650 was determined in NPC tissues and adjacent nontumor tissues using qRT-PCR. Then the relationship between miR-3650 expression and clinicopathological features as well as survival were analyzed. RESULTS: The expression of miR-3650 was significant higher in NPC tissues than that in adjacent nontumor tissues (P < 0.001). High expression of miR-3650 was significant correlated with tumor progression and distant metastasis of NPC patients. And patients with high miR-3650 expression have much worse 5-year overall survival (OS) and 5-year progression-free survival (PFS) than those with low expression (all P < 0.0001). Furthermore, Cox regression analysis showed that miR-3650 was an independent risk predictor for OS and PFS in NPC patients (all P = 0.000). CONCLUSION: Our results demonstrated for the first time that miR-3650 was markedly upregulated in NPC tissues and positively associated with tumor progression and poor survival, suggesting that miR-3650 may be a potential novel prognostic biomarker and therapeutic target for NPC patients.

Raltitrexed as a synergistic hyperthermia chemotherapy drug screened in patient-derived colorectal cancer organoids.

OBJECTIVE: Organoids have recently been used as in vitro models to screen chemotherapy drugs in combination with hyperthermia treatment in colorectal cancer. Our research aimed to establish a library of patient-derived colorectal cancer organoids to evaluate synergism between chemotherapy drugs and hyperthermia; validate an index of the hyperthermia chemotherapy sensitization enhancement ratio (HCSER) to identify the chemotherapeutics most enhanced by hyperthermia; and recommend chemotherapy drugs for hyperthermic intraperitoneal treatment. METHODS: Organoids were grown from cells extracted from colorectal cancer patient samples or colorectal cancer cell lines. Cells from both sources were encapsulated in 3D Matrigel droplets, which were formulated in microfluidics and phase-transferred into identical cell-laden Matrigel microspheres. The microspheres were seeded in 96-well plates, with each well containing a single microsphere that developed into an organoid after 7 days. The organoids were used to evaluate the efficacy of chemotherapy drugs at both 37°C as a control and 43°C for 90 min to examine hyperthermia synergism. Cell viability was counted with 10% CCK8. RESULTS: We successfully established a library of colorectal cancer organoids from 22 patient parental tumors. We examined the hyperthermia synergism of 7 commonly used hyperthermic intraperitoneal chemotherapy drugs. In 11 of the 22 patient organoids, raltitrexed had significant hyperthermia synergism, which was indexed as the highest HCSER score within each patient group. CONCLUSIONS: Our results primarily demonstrated the use of patient-derived colorectal cancer organoids as in vitro models to evaluate hyperthermia synergistic chemotherapeutics. We found that hyperthermia enhanced the effect of raltitrexed the most among the common anti-colorectal cancer drugs.

Rab1A promotes cancer metastasis and radioresistance through activating GSK-3ß/Wnt/ß-catenin signaling in nasopharyngeal carcinoma.

Many articles have reported that Rab1A was overexpressed in a variety of human cancers and involved in tumor progression and metastasis. However, the biological function and molecular mechanism of Rab1A in nasopharyngeal carcinoma (NPC) remained unknown until now. Here we found that Rab1A overexpression is a common event and was positively associated with distant metastasis and poor prognosis of NPC patients. Functionally, Rab1A depletion inhibited the migration and EMT phenotype of NPC cells, whereas Rab1A overexpression led to the opposite effect. Furthermore, we reveal an important role for Rab1A protein in the induction of radioresistance via regulating homologous recombination (HR) signaling pathway. Mechanistically, Rab1A activated Wnt/ß-catenin signaling by inhibiting the activity of GSK-3ß via phosphorylation at Ser9. Then Wnt/ß-catenin signaling induced NPC cells radioresistance and metastasis through nuclear translocation of ß-catenin and transcription upregulation of HR pathway-related and EMT-related genes expression. In general, this study shows that Rab1A may serve as a potential biomarker for predicting prognosis in NPC patients. Targeting Rab1A and Wnt/ß-catenin signaling may hold promise to overcome NPC radioresistance.

Beneficial effects of Cripto-1 for transarterial chemoembolization in hepatocellular carcinoma.

Cripto-1 may act as an independent predictor for prognosis in hepatocellular carcinoma (HCC). However, the function of Cripto-1 in HCC cells and its response to postoperative transarterial chemoembolization (TACE) in HCC patients remains unclearly. Up-regulated Cripto-1 expression boosted the ability of cell proliferation, migration and invasion in HCC cells in vitro. While opposite results were observed in HCC cells with down-regulated Cripto-1 expression. Cripto-1 expression was correlated with epithelial-mesenchymal transition (EMT) relevant biomarkers. Furthermore, in high Cripto-1 expression patients, those with adjuvant TACE had favorable TTR and OS times. On contrary, adjuvant TACE may promote tumor recurrence but had no influence on OS time in patients with low Cripto-1 expression. In different subgroups of vascular invasion, larger tumor size or liver cirrhosis, patients with adjuvant TACE had longer TTR and OS times than those without TACE in patients with high Cripto-1 expression, while they could not obtain benefits from adjuvant TACE in patients with low-expressed Cripto-1 expression. In conclusion, Cripto-1 may be a potential prognostic factor in predicting outcome of HCC patients with TACE therapy, and combined with Cripto-1 and tumor features may be helpful to stratify patients with respect to prognosis and response to adjuvant TACE.

Significance and prognostic role of human epidermal growth factor receptor 2 and RAB1A expression in gastric cancer.

Human epidermal growth factor receptor 2 (HER-2) has an important clinical role in various cancers. However, the prognostic impact of HER-2 in gastric cancer (GC) is controversial. RAB1A is an important small molecule in the mechanistic target of rapamycin signalling pathway, which is one of the downstream signalling pathways of the epidermal growth factor receptor family. In recent years, the aberrant expression of RAB1A has been reported in a number of tumours, but its regulation in GC has not been extensively examined. Therefore, the present study investigated the expression pattern and prognostic significance of HER-2 and RAB1A in gastric adenocarcinoma (CAG). A comprehensive analysis was performed to examine the expression level of HER-2 and RAB1A in 280 cases of paired paraffin-embedded GAC tissues and an additional 120 archived GAC tissue samples. HER-2 and RAB1A protein expression was assessed by immunohistochemistry and cases with a 2+ score for HER-2 expression levels were subjected to fluorescence in situ hybridization to determine the HER-2 amplification status. Furthermore, HER-2 and RAB1A mRNA expression was quantified by reverse transcription-quantitative polymerase chain reaction. The comparison of continuous data between two groups was performed using a paired-samples t-test. Clinical correlations were determined using Pearson's Chi-square and Fisher's exact tests. Kaplan-Meier survival curves were used to estimate overall survival (OS). Cox proportional hazards models were used to determine associations between HER-2 and RAB1A expression and outcomes. Regression analyses were performed to detect the correlation between the mRNA levels of HER-2 and RAB1A in GAC tissues. It was observed that RAB1A was significantly overexpressed in GAC tissues compared with normal tissues (P<0.001). Approximately 12.86% of the 280 GAC patients had HER-2 amplification. Additionally, RAB1A expression was significantly associated with a short OS (P<0.001) but there were no significant differences in survival between the HER-2 high-expression group and the HER-2 low-expression group. Additionally, the co-expression of HER-2 and RAB1A indicated poorer OS than the overexpression of each protein (P=0.001), and the two factors were significantly positively correlated in GAC (P=0.012). These findings may be used to further explore the molecular mechanisms and regulatory associations among signalling pathways in GC.

Epithelial cell adhesion molecule overexpression regulates epithelial-mesenchymal transition, stemness and metastasis of nasopharyngeal carcinoma cells via the PTEN/AKT/mTOR pathway.

Epithelial cell adhesion molecule (EpCAM) is known to be highly expressed in a variety of epithelial carcinomas, and it is involved in cell adhesion and proliferation. However, its expression profile and biological function in nasopharyngeal carcinoma (NPC) remains unclear. In this study, higher expression of EpCAM was found in NPC samples compared with non-cancer nasopharyngeal mucosa by qRT-PCR. Additionally, immunohistochemistry (IHC) analysis of NPC specimens from 64 cases showed that high EpCAM expression was associated with metastasis and shorter survival. Multivariate survival analysis identified high EpCAM expression as an independent prognostic factor. Ectopic EpCAM expression in NPC cells promoted epithelial-mesenchymal transition (EMT), induced a cancer stem cell (CSC)-like phenotype, and enhanced metastasis in vitro and in vivo without an effect on cell proliferation. Notably, EpCAM overexpression reduced PTEN expression and increased the level of AKT, mTOR, p70S6K and 4EBP1 phosphorylation. Correspondingly, an AKT inhibitor and rapamycin blocked the effect of EpCAM on NPC cell invasion and stem-like phenotypes, and siRNA targeting PTEN rescued the oncogenic activities in EpCAM knockdown NPC cells. Our data demonstrate that EpCAM regulates EMT, stemness and metastasis of NPC cells via the PTEN/AKT/mTOR pathway.

Decreased expression of lncRNA VPS9D1-AS1 in gastric cancer and its clinical significance.

BACKGROUND: A recent study has demonstrated that the long non-coding RNA VPS9D1-AS1 is highly expressed in colorectal cancer and predicts poor prognosis. However, roles of VPS9D1-AS1 in gastric cancer remained poorly understood. OBJECTIVE: The aim of this study is to decipher the expression of VPS9D1-AS1 in gastric cancer (GC) patients, so as to assess whether or not it could be used as a novel biomarker for prognosis in gastric cancer patients. METHODS: The expression of VPS9D1-AS1 was examined in cancer tissues and paired adjacent non-tumorous tissues from 126 gastric cancer patients using qRT-PCR. Correlations between the expression of VPS9D1-AS1 and clinicopathological parameters and patients' survival were analyzed. RESULTS: VPS9D1-AS1 expression was downregulated in gastric cancer tissues than that in adjacent non-tumorous tissues (P< 0.001). VPS9D1-AS1 expression level was markedly correlated with tumor size and TNM stage in gastric cancer. Kaplan-Meier analysis showed low expression of VPS9D1-AS1 were correlated with poor overall and disease free survival. On multivariate analysis, the hazard ratio of VPS9D1-AS expression was 0.30 (95% CI = 0.13-0.66, P= 0.003) for overall survival. CONCLUSIONS: Overall, our data suggest that downregulated VPS9D1-AS1 may be used as a novel prognosis predictor of gastric cancer.

Prognostic values of apoptosis-stimulating P53-binding protein 1 and 2 and their relationships with clinical characteristics of esophageal squamous cell carcinoma patients: a retrospective study.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer-related death, and new prognostic biomarkers are urgently needed. Apoptosis-stimulating P53-binding protein 1 (ASPP1) and 2 (ASPP2) have been reported to play important roles in the development, progression, metastasis, and prognosis of cancers, but their roles in ESCC have not been elucidated. In this study, we examined the expression of ASPP1 and ASPP2 in ESCC to evaluate their prognostic values. METHODS: The protein expression of ASPP1, ASPP2, and P53 in 175 specimens of ESCC was detected using immunohistochemical staining; their expression in cancerous and noncancerous tissues was scored according to the staining intensity and the percentage of stained cells. The associations of ASPP1, ASPP2, and P53 with clinicopathologic parameters, overall survival (OS), and disease-free survival (DFS) were analyzed. RESULTS: The protein expression levels of ASPP2 and P53 were significantly higher in cancerous tissues than in paired noncancerous tissues (P < 0.001), whereas the expression levels of ASPP1 in the two groups were similar. In ESCCs, ASPP1 expression was significantly associated with histological differentiation (P = 0.002) and invasive depth (P = 0.014); ASPP2 expression was associated with age (P = 0.029) and histological differentiation (P < 0.001); and P53 expression was associated with age (P = 0.021) and tumor size (P = 0.040). No correlations were found between ASPP1, ASPP2, and P53 expression. Survival analysis revealed that high ASPP2 expression was significantly associated with increased 5-year OS (P = 0.001) and DFS rates (P = 0.010) and that high P53 expression was significantly associated with a reduced 5-year DFS rate of ESCC patients (P = 0.015). Multivariate Cox analysis indicated that ASPP2 was an independent predictor of OS [hazard ratio (HR): 0.541, 95% confidence interval (CI) 0.363-0.804] and DFS (HR: 0.599, 95% CI 0.404-0.888) of ESCC patients and that P53 was an independent predictor of DFS (HR: 2.161, 95% CI 1.100-4.245). CONCLUSIONS: ASPP1 might be involved in the progression of ESCC, and ASPP2 was a potential prognostic biomarker of ESCC and should be evaluated in future studies.

Prognostic impact of pretherapeutic gamma-glutamyltransferase on patients with nasopharyngeal carcinoma.

BACKGROUND: Gamma-glutamyltransferase (GGT) is a membrane-bound enzyme involved in the metabolism of glutathione. Studies suggested that GGT played an important role in the tumor development, progression, invasion and drug resistance and prognosis. The association between GGT and prognosis of patients with nasopharyngeal carcinoma (NPC) was unknown. This study was conducted to investigate the association of pretherapeutic serum level of GGT with clinical-pathological parameters and survival in patients with NPC. METHODS: Two hundred and twenty-two patients with NPC were recruited in this study and were stratified into two GGT risk groups (≤ 34.5 U/L, > 34.5 U/L). The association of pretherapeutic serum GGT levels with clinical-pathological parameters was examined. Univariate and multivariate survival analyses were performed. FINDINGS: The pretherapeutic serum level of GGT was not associated with gender, age, pathology, T stage, N stage, TNM stage, chemotherapy or radiotherapy in patients with NPC. Patients in the high-risk GGT group had a poorer survival than the low-risk GGT group (3-year overall survival, 74.2% vs. 50.2%, P = 0.001; 3-year progression-free survival, 76.4% vs. 47.1%, P < 0.001; 3-year loco-regional relapse-free survival, 76.4% vs. 51.3%, P < 0.001; 3-year distant metastasis-free survival, 89.5% vs. 66.4%, P < 0.001). Multivariate analysis suggested that patients in the high-risk GGT group had 2.117 (95% confidence interval [CI], 1.225 ∼ 3.659, P = 0.007) times the risk of death, 2.836 (95% CI, 1.765 ∼ 4.557, P < 0.001) times the risk of progression, 2.551 (95% CI, 1.573 ∼ 4.138, P < 0.001) times the risk of relapse, and 3.331 (95% CI, 1.676 ∼ 6.622, P < 0.001) times the risk of metastasis compared with those in the low-risk GGT group. CONCLUSION: The pretherapeutic serum level of GGT might serve as a novel independent prognostic factor for overall-survival, progression-free survival, loco-regional relapse-free survival and distant metastasis-free survival in patients with NPC.

NORAD Expression Is Associated with Adverse Prognosis in Esophageal Squamous Cell Carcinoma.

BACKGROUND: NORAD (non-coding RNA-activated by DNA damage) is a conserved, abundant, and broadly expressed long non-coding RNA, which functions to preserve genome stability. However, its prognostic significance in esophageal squamous cell carcinoma (ESCC) remains unclear. MATERIAL AND METHODS: The expression of NORAD was detected by quantitative real-time polymerase chain reaction in pairs of tumorous and adjacent normal tissues derived from 106 ESCC patients. We analyzed the potential relationship between NORAD expression levels in tumor tissues and clinicopathological features of ESCC patients and clinical outcome. RESULTS: The relative expression levels of NORAD were significantly upregulated in tumor tissues (p < 0.001) compared to adjacent normal tissues. In addition, high expression of NORAD was correlated with larger tumor size (p = 0.021) and T stage (p = 0.045). Kaplan-Meier analysis indicated that patients with high NORAD expression had poor overall and disease-free survival (p < 0.001). Moreover, multivariate analysis showed that increased expression of NORAD was an independent predictor of overall survival (p = 0.001). CONCLUSION: Our data indicate that increased NORAD expression might serve as a novel molecular predictor of poor prognosis in ESCC patients and maybe a potential target for diagnosis and gene therapy.

Long noncoding RNA XIST promotes malignancies of esophageal squamous cell carcinoma via regulation of miR-101/EZH2.

The long non-coding RNA XIST is a long non-coding RNA that associates with polycomb repressive complex 2 to regulate X-chromosome inactivation in female mammals. The biological roles as well as the underlying mechanisms of XIST in esophageal squamous cell carcinoma remained yet to be solved. Our data indicated that XIST was significantly upregulated in esophageal squamous cancerous tissues and cancer cell lines, as compared with that in the corresponding non-cancerous tissues and immortalized normal squamous epithelial cells. High XIST expression predicted poor prognosis of esophageal squamous cancer patients. Lentivirus mediated knockdown of XIST inhibited proliferation, migration and invasion of esophageal squamous cancer cells in vitro and suppressed tumor growth in vivo. Knockdown of XIST resulted in elevated expression of miR-101 and decreased expression of EZH2. Further analysis showed that XIST functioned as the competitive endogenous RNA of miR-101 to regulate EZH2 expression. Moreover, enforced expression of EZH2 significantly attenuated the anti-proliferation activity upon XIST knockdown. Conclusively, XIST plays an important role in malignant progression of ESCC via modulation of miR-101/EZH2 axis.