Phosphorylation of androgen receptor by mTORC1 promotes liver steatosis and tumorigenesis.

BACKGROUND AND AIMS: Androgen receptor (AR) has been reported to play an important role in the development and progression of man's prostate cancer. Hepatocellular carcinoma (HCC) is also male-dominant, but the role of AR in HCC remains poorly understood. Mechanistic target of rapamycin complex 1 (mTORC1) also has been reported to be highly activated in HCC. In this study, we aimed to explore the role of AR phosphorylation and its relationship with mTORC1 in hepatocarcinogenesis. APPROACH AND RESULTS: In vitro experiment, we observed that mTORC1 interacts with hepatic AR and phosphorylates it at S96 in response to nutrient and mitogenic stimuli in HCC cells. S96 phosphorylation promotes the stability, nuclear localization, and transcriptional activity of AR, which enhances de novo lipogenesis and proliferation in hepatocytes and induces liver steatosis and hepatocarcinogenesis in mice independently and cooperatively with androgen. Furthermore, high ARS96 phosphorylation is observed in human liver steatotic and HCC tissues and is associated with overall survival and disease-free survival, which has been proven as an independent survival predictor for patients with HCC. CONCLUSIONS: AR S96 phosphorylation by mTORC1 drives liver steatosis and HCC development and progression independently and cooperatively with androgen, which not only explains why HCC is man-biased but also provides a target molecule for prevention and treatment of HCC and a potential survival predictor in patients with HCC.

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.

Identification of a 4-lncRNA signature predicting prognosis of patients with non-small cell lung cancer: a multicenter study in China.

BACKGROUND: Previous findings have indicated that the tumor, nodes, and metastases (TNM) staging system is not sufficient to accurately predict survival outcomes in patients with non-small lung carcinoma (NSCLC). Thus, this study aims to identify a long non-coding RNA (lncRNA) signature for predicting survival in patients with NSCLC and to provide additional prognostic information to TNM staging system. METHODS: Patients with NSCLC were recruited from a hospital and divided into a discovery cohort (n = 194) and validation cohort (n = 172), and detected using a custom lncRNA microarray. Another 73 NSCLC cases obtained from a different hospital (an independent validation cohort) were examined with qRT-PCR. Differentially expressed lncRNAs were determined with the Significance Analysis of Microarrays program, from which lncRNAs associated with survival were identified using Cox regression in the discovery cohort. These prognostic lncRNAs were employed to construct a prognostic signature with a risk-score method. Then, the utility of the prognostic signature was confirmed using the validation cohort and the independent cohort. RESULTS: In the discovery cohort, we identified 305 lncRNAs that were differentially expressed between the NSCLC tissues and matched, adjacent normal lung tissues, of which 15 are associated with survival; a 4-lncRNA prognostic signature was identified from the 15 survival lncRNAs, which was significantly correlated with survivals of NSCLC patients. This signature was further validated in the validation cohort and independent validation cohort. Moreover, multivariate Cox analysis demonstrates that the 4-lncRNA signature is an independent survival predictor. Then we established a new risk-score model by combining 4-lncRNA signature and TNM staging stage. The receiver operating characteristics (ROC) curve indicates that the prognostic value of the combined model is significantly higher than that of the TNM stage alone, in all the cohorts. CONCLUSIONS: In this study, we identified a 4-lncRNA signature that may be a powerful prognosis biomarker and can provide additional survival information to the TNM staging system.

Identification of two microRNA signatures in whole blood as novel biomarkers for diagnosis of nasopharyngeal carcinoma.

BACKGROUND: Early diagnosis is critical to reduce the mortality caused by nasopharyngeal carcinoma (NPC). MicroRNAs (miRNAs) are dysregulated and play important roles in carcinogenesis. Therefore, this study aimed to identify diagnostically relevant circulating miRNA signatures in patients with NPC. METHODS: Total RNA was extracted from whole blood samples obtained from 120 patients with NPC, 30 patients with head-neck tumors (HNT), and 30 healthy subjects (HSs), and examined by using a custom microarray. The expression levels of four miRNAs identified by using the microarray were validated with quantitative real-time reverse transcription polymerase chain reaction. The 120 patients with NPC and 30 HSs were randomly assigned to training group-1 and validation group-1, respectively. By using significance analysis of microarray (SAM), the specific miRNA expression profiles in whole blood from patients with NPC are obtained. By using lasso regression and adaptive boosting, a diagnostic signature was identified in training group-1, and its accuracy was verified in validation group-1. By using the same methods, another signature to distinguish patients with NPC from those with HNT and HSs was identified in training group-2 and confirmed in validation group-2. RESULTS: There were 117 differentially expressed miRNAs (upregulated and downregulated fold change ≥ 1.5) between the patients with NPC and HSs, among which an 8-miRNA signature was identified with 96.43% sensitivity and 100% specificity [area under the curve (AUC) = 0.995] to diagnose NPC in training group-1 and 86.11% sensitivity and 88.89% specificity (AUC = 0.941) in validation group-1. Compared with traditional Epstein-Barr virus (EBV) seromarkers, this signature was more specific for NPC. Furthermore, a 16-miRNA signature to differentiate NPC from HNT and HS (HNT-HS) was established from 164 differentially expressed miRNAs, which diagnosed NPC and HNT-HS with 100% accuracy (AUC = 1.000) in training group-2 and 87.04% (AUC = 0.924) in validation group-2. CONCLUSIONS: The present study identified two miRNA signatures for the highly accurate diagnosis and differential diagnosis of patients with NPC from HSs and patients with HNT. The identified miRNAs might represent novel serological biomarkers and potential therapeutic targets for NPC.

CLDN14 is epigenetically silenced by EZH2-mediated H3K27ME3 and is a novel prognostic biomarker in hepatocellular carcinoma.

Trimethylation of lysine 27 on histone H3 (H3K27ME3) is a transcription-suppressive histone mark mediated by enhancer of zeste homolog 2 (EZH2). We have previously suggested that EZH2-mediated H3K27ME3 plays a critical oncogenic role in human hepatocellular carcinoma (HCC) aggressiveness. However, the direct downstream targets of EZH2-H3K27ME3 and the molecular mechanisms by which regulates HCC pathogenesis remain unclear. In this study, we used chromatin immunoprecipitation together with high-throughput sequencing (ChIP-seq) and gene expression profiling by microarray analysis to assess genome-wide chromatin occupancy of H3K27ME3 in HCC cells. We identified that claudin14 (CLDN14) is a potentially direct target for EZH2-mediated H3K27ME3 in HCC. In a large cohort of clinical HCC tissues, we found that low expression of CLDN14 was significantly associated with advanced tumor stage and determined to be an independent predictor of shortened survival of HCC patients. Next, functional experiment demonstrated that depletion of CLDN14 substantially restored EZH2-silenced HCC cells motility and invasive capacities and supported cell epithelial-mesenchymal transition (EMT). Furthermore, downregulation of CLDN14 dramatically re-enhanced the wnt/ß-catenin signaling activity in EZH2-silenced HCC cells by increasing the levels of active ß-catenin and promoting the nuclear localization of ß-catenin. These results, collectively, uncover that CLDN14 is a novel direct target of EZH2-mediated H3K27ME3, and provide an explanation for the aggressive nature of HCC with downregulation of CLDN14 and the underling mechanism that links the tumor suppressor CLDN14 to the wnt/ß-catenin signaling pathway.

Elevated levels of plasma D-dimer predict a worse outcome in patients with nasopharyngeal carcinoma.

BACKGROUND: Hemostatic alterations occur during the development of cancer. Plasma D-dimer is a hypercoagulability and fibrinolytic system marker that is increased in patients with various solid tumours. The aim of this study was to evaluate the hemostatic status of nasopharyngeal carcinoma (NPC) patients by assessing plasma D-dimer levels to investigate its value as a prognostic marker. METHODS: We retrospectively analysed 717 patients with nasopharyngeal carcinoma, and we applied Cox regression and log-rank tests to assess the association of D-dimer levels with disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival (OS). D-dimer levels were measured using a quantitative D-dimer latex agglutination assay. RESULTS: Using the 3rd quartile values (0.8 µg/L) as the optimal cut-offs, we found that patients with high D-dimer levels have a shorter 3-year DFS, (79%, 95%CI (73.1-84.9)) vs. (69%, 95%CI (59.2-78.8)), DMFS (87%, 95%CI (83.1-90.9)) vs. (77%, 95%CI (69.2-84.8)), and overall survival (82%, 95%CI (76.1-87.9)) vs. (76%, 95%CI (66.2-85.8)). Multivariate analysis revealed that pre-treatment D-dimer levels and EBV DNA were significant independent factors for DFS, DMFS, and OS in NPC patients. Subgroup analyses indicated that the plasma D-dimer levels could effectively stratify patient prognosis for early cancer, advanced stage cancer, and patients with EBV DNA ≥4000 copies/ml. CONCLUSIONS: High D-dimer levels were associated with poor disease-free survival, distant metastasis-free survival, overall survival, and increased risk of mortality in NPC patients. Prospective trials are required to assess the prognostic value of D-dimer levels.

The telomere/telomerase binding factor PinX1 is a new target to improve the radiotherapy effect of oesophageal squamous cell carcinomas.

Chemoradiotherapy (CRT) is a standard treatment for oesophageal squamous cell carcinoma (ESCC) in its advanced stages. The telomerase/telomere interacting protein PinX1 contributes to telomere maintenance, tumourigenicity, and influences the DNA damage agent-induced apoptotic response in telomerase-positive cancer cells. However, the clinical and biological significance of PinX1 in human ESCCs remains unclear. We examined the expression dynamics of PinX1 by immunohistochemistry in a learning cohort (n = 98) and a validation cohort (n = 59) of ESCC patients treated with definite chemoradiotherapy (CRT). A series of in vivo and in vitro assays were performed to elucidate the effect of PinX1 on ESCC cells' CRT response and underlying mechanisms. Knockdown of PinX1 did not affect ESCC cells' chemosensitivities to 5-fluorouracil and cisplatin, but substantially increased ESCC cells' therapeutic efficacy of radiation both in vitro and in vivo. Ectopic overexpression of PinX1 dramatically enhanced ESCC cells' resistance to radiotherapy. Furthermore, we demonstrated that PinX1 resistance to radiotherapy (RT) was attributed to PinX1 maintaining telomere stability, reducing ESCC cell death by RT-induced mitosis catastrophe (MC). High expression of Pinx1 correlated positively with ESCC's resistance to CRT, and was a strong and independent predictor for short disease-specific survival (DSS) of ESCC patients. Our data suggest that PinX1 could serve as a novel predictor for a CRT response to ESCC patients, and the pathway of PinX1-mediated telomere stability might represent a new target to improve the RT effect of ESCC.

TRIM29 modulates proteins involved in PTEN/AKT/mTOR and JAK2/STAT3 signaling pathway and suppresses the progression of hepatocellular carcinoma.

Tripartite motif-containing 29 (TRIM29), also known as the ataxia telangiectasia group D-complementing (ATDC) gene, has been reported to play an oncogenic or tumor suppressive role in developing different tumors. So far, its expression and biological functions in hepatocellular carcinoma (HCC) remain unclear. We investigated TRIM29 expression pattern in human HCC samples using quantitative RT-PCR and immunohistochemistry. Relationships between TRIM29 expression level, clinical prognostic indicators, overall survival (OS), and disease-free survival (DFS) were evaluated by Kaplan-Meier analysis and Cox proportional hazards model. A series of in vitro experiments and a xenograft tumor model were conducted to detect the functions of TRIM29 in HCC cells. RNA sequencing, western blotting, and immunochemical staining were performed to assess the molecular regulation of TRIM29 in HCC. We found that the mRNA and protein levels of TRIM29 were significantly reduced in HCC samples, compared with adjacent noncancerous tissues, and were negatively correlated with poor differentiation of HCC tissues. Survival analysis confirmed that lower TRIM29 expression significantly correlated with shorter OS and DFS of HCC patients. TRIM29 overexpression remarkably inhibited cell proliferation, migration, and EMT in HCC cells, whereas knockdown of TRIM29 reversed these effects. Moreover, deactivation of the PTEN/AKT/mTOR and JAK2/STAT3 pathways might be involved in the tumor suppressive role of TRIM29 in HCC. Our findings indicate that TRIM29 in HCC exerts its tumor suppressive effects through inhibition of the PTEN/AKT/mTOR and JAK2/STAT3 signaling pathways and may be used as a potential biomarker for survival in patients with HCC.

Cholesterol inhibition enhances antitumor response of gilteritinib in lung cancer cells.

Repositioning approved antitumor drugs for different cancers is a cost-effective approach. Gilteritinib was FDA-approved for the treatment of FLT3-mutated acute myeloid leukemia in 2018. However, the therapeutic effects and mechanism of Gilteritinib on other malignancies remain to be defined. In this study, we identified that gilteritinib has an inhibitory effect on lung cancer cells (LCCs) without FLT3 mutation in vitro and in vivo. Unexpectedly, we found that gilteritinib induces cholesterol accumulation in LCCs via upregulating cholesterol biosynthetic genes and inhibiting cholesterol efflux. This gilteritinib-induced cholesterol accumulation not only attenuates the antitumor effect of gilteritinib but also induces gilteritinib-resistance in LCCs. However, when cholesterol synthesis was prevented by squalene epoxidase (SQLE) inhibitor NB-598, both LCCs and gilteritinib-resistant LCCs became sensitive to gilteritinib. More importantly, the natural cholesterol inhibitor 25-hydroxycholesterol (25HC) can suppress cholesterol biosynthesis and increase cholesterol efflux in LCCs. Consequently, 25HC treatment significantly increases the cytotoxicity of gilteritinib on LCCs, which can be rescued by the addition of exogenous cholesterol. In a xenograft model, the combination of gilteritinib and 25HC showed significantly better efficacy than either monotherapy in suppressing lung cancer growth, without obvious general toxicity. Thus, our findings identify an increase in cholesterol induced by gilteritinib as a mechanism for LCC survival, and highlight the potential of combining gilteritinib with cholesterol-lowering drugs to treat lung cancer.

CircATF6 inhibits hepatocellular carcinoma progression by suppressing calreticulin-mediated Wnt/ß-catenin signaling pathway.

Circular RNAs (circRNAs) are covalently closed, single-stranded RNAs that play critical roles in various biological processes and diseases, including cancers. However, the functions and mechanisms of circRNAs in hepatocellular carcinoma (HCC) need further clarification. Here, we identified and confirmed that circATF6 is downregulated in HCC tissues and negatively associated with the overall survival of HCC patients. Ectopic overexpression of circATF6 inhibits malignant phenotypes of HCC cells in vitro and in vivo, while knockdown of circATF6 had opposite effects. Mechanistically, we found that circATF6 bound to calreticulin (CALR) protein and acted as a scaffold to enhance the interaction of CALR with calpain2 (CAPN2), which promoted the degradation of CALR by its enzymatic activity. Moreover, we found that circATF6 inhibited HCC cells by suppressing CALR-mediated wnt/ß-catenin signaling pathway. Taken together, our findings suggest that circATF6 is a potential prognostic biomarker and therapeutic target for HCC.

Two somatic mutations in the androgen receptor N-terminal domain are oncogenic drivers in hepatocellular carcinoma.

The androgen receptor (AR) plays an important role in male-dominant hepatocellular carcinoma, and specific acquired somatic mutations of AR have been observed in HCC patients. Our previous research have established the role of AR wild type as one of the key oncogenes in hepatocarcinogenesis. However, the role of hepatic acquired somatic mutations of AR remains unknown. In this study, we identify two crucial acquired somatic mutations, Q62L and E81Q, situated close to the N-terminal activation function domain-1 of AR. These mutations lead to constitutive activation of AR, both independently and synergistically with androgens, making them potent driver oncogene mutations. Mechanistically, these N-terminal AR somatic mutations enhance de novo lipogenesis by activating sterol regulatory element-binding protein-1 and promote glycogen accumulation through glycogen phosphorylase, brain form, thereby disrupting the AMPK pathway and contributing to tumorigenesis. Moreover, the AR mutations show sensitivity to the AMPK activator A769662. Overall, this study establishes the role of these N- terminal hepatic mutations of AR as highly malignant oncogenic drivers in hepatocarcinogenesis and highlights their potential as therapeutic targets for patients harboring these somatic mutations.

PinX1 suppresses bladder urothelial carcinoma cell proliferation via the inhibition of telomerase activity and p16/cyclin D1 pathway.

BACKGROUND: PIN2/TRF1-interacting telomerase inhibitor1 (PinX1) was recently suggested as a putative tumor suppressor in several types of human cancer, based on its binding to and inhibition of telomerase. Moreover, loss of PinX1 has been detected in many human malignancies. However, the possible involvement of PinX1 and its clinical/prognostic significance in urothelial carcinoma of the bladder (UCB) are unclear. METHODS: The PinX1 expression profile was examined by quantitative real-time polymerase chain reaction (qRT-PCR), western blotting, and immunohistochemistry (IHC) in UCB tissues and adjacent normal urothelial bladder epithelial tissues. PinX1 was overexpressed and silenced in UCB cell lines to determine its role in tumorigenesis, development of UCB, and the possible mechanism. RESULTS: PinX1 expression in UCB was significantly down-regulated at both mRNA and protein level as compared with that in normal urothelial bladder epithelial tissues. PinX1 levels were inversely correlated with tumor multiplicity, advanced N classification, high proliferation index (Ki-67), and poor survival (P < 0.05). Moreover, overexpression of PinX1 in UCB cells significantly inhibited cell proliferation in vitro and in vivo, whereas silencing PinX1 dramatically enhanced cell proliferation. Overexpression of PinX1 resulted in G1/S phase arrest and cell growth/proliferation inhibition, while silencing PinX1 led to acceleration of G1/S transition, and cell growth/proliferation promotion by inhibiting/enhancing telomerase activity and via the p16/cyclin D1 pathway. CONCLUSIONS: These findings suggest that down-regulation of PinX1 play an important role in the tumorigenesis and development of UCB and that the expression of PinX1 as detected by IHC is an independent molecular marker in patients with UCB.

Overexpression of YAP 1 contributes to progressive features and poor prognosis of human urothelial carcinoma of the bladder.

BACKGROUND: Yes-associated protein 1 (YAP 1), the nuclear effector of the Hippo pathway, is a key regulator of organ size and a candidate human oncogene in multiple tumors. However, the expression dynamics of YAP 1 in urothelial carcinoma of the bladder (UCB) and its clinical/prognostic significance are unclear. METHODS: In this study, the methods of quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting and immunohistochemistry (IHC) were utilized to investigate mRNA/ protein expression of YAP 1 in UCBs. Spearman's rank correlation, Kaplan-Meier plots and Cox proportional hazards regression model were used to analyze the data. RESULTS: Up-regulated expression of YAP 1 mRNA and protein was observed in the majority of UCBs by qRT-PCR and Western blotting, when compared with their paired normal bladder tissues. By IHC, positive expression of YAP 1 was examined in 113/213 (53.1%) of UCBs and in 6/86 (7.0%) of normal bladder specimens tissues. Positive expression of YAP 1 was correlated with poorer differentiation, higher T classification and higher N classification (P < 0.05). In univariate survival analysis, a significant association between positive expression of YAP 1 and shortened patients' survival was found (P < 0.001). In different subsets of UCB patients, YAP 1 expression was also a prognostic indicator in patients with grade 2 (P = 0.005) or grade 3 (P = 0.046) UCB, and in patients in pT1 (P = 0.013), pT2-4 (P = 0.002), pN- (P < 0.001) or pT2-4/pN- (P = 0.004) stage. Importantly, YAP 1 expression (P = 0.003) together with pT and pN status (P< 0.05) provided significant independent prognostic parameters in multivariate analysis. CONCLUSIONS: Our findings provide evidences that positive expression of YAP 1 in UCB may be important in the acquisition of an aggressive phenotype, and it is an independent biomarker for poor prognosis of patients with UCB.

Overexpression of EIF5A2 promotes colorectal carcinoma cell aggressiveness by upregulating MTA1 through C-myc to induce epithelial-mesenchymaltransition.

BACKGROUND AND AIMS: The authors have previously isolated a putative oncogene, eukaryotic initiation factor 5A2 (EIF5A2) from 3q26. In this study, EIF5A2 was characterised for its role in colorectal carcinoma (CRC) aggressiveness and underlying molecular mechanisms. METHODS: The expression dynamics of EIF5A2 were examined by immunohistochemistry in a cohort of carcinomatous and non-neoplastic colorectal tissues and cells. A series of in-vivo and in-vitro assays was performed to elucidate the function of EIF5A2 in CRC and its underlying mechanisms. RESULTS: The overexpression of EIF5A2 was examined by immunohistochemistry in 102/229 (44.5%) CRC patients, and it was significantly correlated with tumour metastasis and determined to be an independent predictor of shortened survival (p<0.05). Ectopic overexpression of EIF5A2 in CRC cells enhanced cell motility and invasion in vitro and tumour metastasis in vivo, and induced epithelial-mesenchymal transition (EMT). The depletion of EIF5A2 expression prevented CRC cell invasiveness and inhibited EMT. Importantly, the metastasis-associated protein 1 (MTA1) gene was identified as a potential downstream target of EIF5A2 in CRC cells, and knockdown of MTA1 eliminated the augmentation of carcinoma cell migration, invasion and EMT by ectopic EIF5A2. The overexpression of EIF5A2 in CRC cells substantially enhanced the enrichment of c-myc on the promoter of MTA1, and MTA1 upregulation by EIF5A2 was partly dependent on c-myc. CONCLUSION: The data suggest that EIF5A2 plays an important oncogenic role in CRC aggressiveness by the upregulation of MTA1 to induce EMT, and EIF5A2 could be employed as a novel prognostic marker and/or effective therapeutic target for CRC.

Overexpression of the secretory small GTPase Rab27B in human breast cancer correlates closely with lymph node metastasis and predicts poor prognosis.

BACKGROUND: The secretory small GTPase Rab27b was recently identified as an oncogene in breast cancer (BC) in vivo and in vitro studies. This research was designed to further explore the clinical and prognostic significance of Rab27B in BC patients. METHODS: The mRNA/protein expression level of Rab27B was examined by performing Real-time PCR, western blot, and immunohistochemistry (IHC) assays in 12 paired BC tissues and matched adjacent noncancerous tissues (NAT). Then we carried out IHC assay in a large cohort of 221 invasive BC tissues, 22 normal breast tissues, 40 fibroadenoma (FA), 30 ductual carcinoma in situ (DCIS) and 40 metastatic lymph nodes (LNs). The receiver operating characteristic curve method was applied to obtain the optimal cutoff value for high Rab27B expression. Epithelial-mesenchymal transition (EMT) marker expression levels were detected in relation to Rab27B expression. RESULTS: We observed that the increased expression of Rab27B was dependent upon the magnitude of cancer progression (P < 0.001). The elevated expression of Rab27B was closely correlated with lymph node metastasis, advanced clinical stage, ascending pathology classification, and positive ER status. Furthermore, patients with high expression of Rab27B had inferior survival outcomes. Multivariate Cox regression analysis proved that Rab27B was a significantly independent risk factor for patients' survival (P < 0.001). Furthermore, a significant positive relationship was observed between Rab27B expression and elevated mesenchymal EMT markers. CONCLUSION: Our findings suggest that overexpression of Rab27B in BC coincides with lymph node metastasis and acquisition of a poor prognostic phenotype.

The nucleotide polymorphisms within the Epstein-Barr virus C and Q promoters from nasopharyngeal carcinoma affect transcriptional activity in vitro.

Epstein-Barr virus (EBV) is a ubiquitous human gamma herpesvirus that is associated with Burkitt's lymphoma (BL), gastric carcinoma, nasopharyngeal carcinoma (NPC), and NK/T-cell lymphoma. Two viral promoters, Cp and Qp, are important for EBV latent infection. The latency Cp, which is used in primary infection, drives expression of the full spectrum of EBV nuclear antigens. Qp is active in EBV-associated tumors and drives the latency I/II expression pattern. In this study, we determined nucleotides polymorphisms in the Cp and Qp promoter regions in peripheral blood mononuclear cells (PBMCs) from Cantonese healthy carriers and in biopsies of NPC, nasal NK/T lymphoma, BL, and gastric carcinoma. The sequence changes of -12G>T and +69 C>T in Cp and -197 G>A and +1 G>C in Qp were frequently identified in NPC. Transient transfection studies using luciferase gene reporters revealed a significant reduction (57.11%) in gene expression from the Cp +69T variant and increased expression (43.5%) from the Qp +1C variant compared to the prototype, suggesting that these sequence variations affect promoter activity. Our results indicate that the nucleotides polymorphisms in Cp and Qp occur frequently in NPC and might contribute to the oncogenesis of EBV.

Combination Treatment With Inhibitors of ERK and Autophagy Enhances Antitumor Activity of Betulinic Acid in Non-small-Cell Lung Cancer In Vivo and In Vitro.

Aberrant activation of the Ras-ERK signaling pathway drives many important cancer phenotypes, and several inhibitors targeting such pathways are under investigation and/or approved by the FDA as single- or multi-agent therapy for patients with melanoma and non-small-cell lung cancer (NSCLC). Here, we show that betulinic acid (BA), a natural pentacyclic triterpenoid, inhibits cell proliferation, and induces apoptosis and protective autophagy in NSCLC cells. Thus, the cancer cell killing activity of BA is enhanced by autophagy inhibition. Mitogen-activated protein kinases, and especially ERK that facilitates cancer cell survival, are also activated by BA treatment. As such, in the presence of ERK inhibitors (ERKi), lung cancer cells are much more sensitive to BA. However, the dual treatment of BA and ERKi results in increased protective autophagy and AKT phosphorylation. Accordingly, inhibition of AKT has a highly synergistic anticancer effect with co-treatment of BA and ERKi. Notably, autophagy inhibition by hydroxychloroquine (HCQ) increases the response of lung cancer cells to BA in combination with ERKi. In vivo, the three-drug combination (BA, ERKi, and HCQ), resulted in superior therapeutic efficacy than single or dual treatments in the xenograft mouse model. Thus, our study provides a combined therapy strategy that is a highly effective treatment for patients with NSCLC.

Lnc-GAN1 expression is associated with good survival and suppresses tumor progression by sponging mir-26a-5p to activate PTEN signaling in non-small cell lung cancer.

BACKGROUND: Long non-coding RNAs (lncRNAs) play vital roles in the development and progression of non-small-cell lung cancer (NSCLC); however, the role of most lncRNAs in NSCLC remains unknown. This study explored the clinical significance, biological function and underlying mechanism of lnc-GAN1 in NSCLC. METHODS: With a custom lncRNA microarray we found that lnc-GAN1 is markedly downregulated in NSCLC tissues. Then lnc-GAN1 expression level was measured using qRT-PCR in NSCLC tissues and cell lines. Survival was assessed using the Kaplan-Meier method. The biological functions of lnc-GAN1 in lung cancer cells were evaluated in vitro and in vivo. RNA fluorescence in situ hybridization and subcellular localization assays revealed the subcellular distribution of lnc-GAN1 in cells. Bioinformatic analysis was adopted to predict miRNAs and signaling pathways regulated by lnc-GAN1. RNA immunoprecipitation and Dual-luciferase reporter assays were used to assess the interaction between lnc-GAN1 and miR-26a-5p in lung cancer cells. RESULTS: lnc-GAN1 is downregulated in HCC tissues and associated with larger tumor size and poor overall survival and disease-free survival; its ectopic expression suppresses cell proliferation, colony formation, and cell cycle progression and induces apoptosis in NSCLC cells; it also inhibits tumor growth in the NSCLC xenograft model. We further proved that lnc-GAN1 is localized in cytoplasm and transcribed independently from its parental gene GAN. Mechanistically, lnc-GAN1 acts as a sponge for miR-26a-5p by two seed sequences, and the two non-coding RNAs have a negative relationship in NSCLC tissues; we further prove that PTEN is a direct target of miR-26a-5p and lnc-GAN1 inhibits cell cycle signaling pathway by activating PTEN, whose expression level correlated negatively with miR-26a-5p level but positively with lnc-GAN1 level in NSCLC samples. CONCLUSIONS: Lnc-GAN1 is downregulated and associated with poor survival of NSCLC patients, and mechanistically acts as a tumor suppressor via sponging and inhibiting miR-26a-5p to upregulate PTEN. This study provides a potential prognostic biomarker and treatment target for NSCLC.

EZH2 supports ovarian carcinoma cell invasion and/or metastasis via regulation of TGF-beta1 and is a predictor of outcome in ovarian carcinoma patients.

It was suggested that the enhancer of zeste homolog 2 (EZH2) gene is a putative candidate oncogene in several types of human cancer. The potential oncogenic role of EZH2 and its clinical/prognostic significance, however, in ovarian carcinoma are unclear. In this study, EZH2 expression was examined by immunohistochemistry (IHC) in cohorts of normal and tumorous ovarian tissues. High expression of EZH2 was examined in none of the normal ovaries, in 3% of the cystadenomas, in 23% of the borderline tumors and in 50% of the ovarian carcinomas, respectively. In the ovarian carcinomas, high expression of EZH2 was positively correlated with an ascending histological grade and/or advanced stage of the disease (P < 0.05). Moreover, high expression of EZH2 in ovarian carcinoma was determined to be a strong and an independent predictor of short overall survival (P < 0.05). In ovarian carcinoma HO-8910 and UACC-326 cell lines, EZH2 knockdown by RNA interference led to a G(1) phase cell cycle arrest, reduced cell growth/proliferation and inhibited cell migration and/or invasion in vitro. In addition, EZH2 knockdown was found to reduce transforming growth factor-beta1 (TGF-beta1) expression and increase E-cadherin expression either in the transcript or in the protein levels. Furthermore, a significant positive correlation between overexpression of EZH2 and TGF-beta1 in ovarian carcinoma tissues was observed (P < 0.001). These findings suggest a potential important role of EZH2 in the control of cell migration and/or invasion via the regulation of TGF-beta1 expression, and the high expression of EZH2, as detected by IHC, is an independent molecular marker for shortened survival time of patients with ovarian carcinoma.

Evaluation of serum clusterin as a surveillance tool for human hepatocellular carcinoma with hepatitis B virus related cirrhosis.

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is a common human cancer worldwide. The levels of serum clusterin in HCC patients and its potential diagnostic significance is not clear. We aimed to evaluate the clinical use of serum clusterin levels as a surveillance tool for HCC with hepatitis B virus (HBV) related cirrhosis. METHODS: Twenty-two cases of healthy subjects, 31 cases of HBV carriers, 26 patients with chronic hepatitis B, 29 patients with cirrhosis, and 76 patients with HCC were enrolled in this study. Serum levels of clusterin were measured by a sandwich enzyme-linked immunosorbent assay. RESULTS: The serum clusterin levels in HCC patients were significantly lower than that in healthy, HBV carriers and chronic hepatitis B, but statistically higher than in cirrhosis patients. Receiver operator characteristic (ROC) curve indicated that a serum clusterin value of 50 microg/mL yielded the best sensitivity (91%) and specificity (83%) for differentiating HCC patients with HBV-related cirrhosis from those with HBV-related cirrhosis. The optimal alpha fetoprotein (AFP) cutoff value was 15 ng/mL and was inferior to the clusterin value of 50 microg/mL, the area under the ROC curves being 0.937 versus 0.781, respectively (P < 0.05). CONCLUSIONS: Serum clusterin was more sensitive and specific than serum AFP for differentiating HCC patients with HBV-related cirrhosis from those with HBV-related liver cirrhosis, and may be a useful surveillance tool of HCC based on HBV-related cirrhosis.