A Novel Four­Gene Biomarker for Tobacco Smoking-Induced Colorectal Cancer Progression.

INTRODUCTION: Cigarette smoking greatly promotes the progression and poor prognosis of colorectal cancer (CRC) patients, with the molecular mechanism still not fully clear. METHODS: In this study, CRC cells were exposed to tobacco-specific nitrosamine 4­(methylnitrosamino)­1­(3­pyridyl)-1­butanone (NNK), and the differentially expressed smoking-related genes were identified based on both NNK-induced CRC cells and a total of 763 CRC tissues from The Cancer Genome Atlas cohort. Cox regression analysis, receiver operating characteristic curve and Kaplan-Meier plot were used to establish the risk score model for CRC prognosis. Moreover, quantitative real-time-PCR, western blotting, colony formation, migration, and invasion assays were performed to verify the core differentially expressed smoking-related gene and its molecular function in NNK-induced CRC progression. RESULTS: Results indicated NNK significantly enhanced CRC cell proliferation, migration and invasion. Moreover, a four-gene signature containing AKR1B10, CALB2, PLAC1, and GNA15 was established as a CRC prognosis marker. Among these four genes, AKR1B10 was further validated as the core gene, and its expression was significantly inhibited after NNK exposure in CRC cells. Results of gene enrichment analysis and western blotting suggested AKR1B10 might reduce the malignant progression of NNK-induced CRC cells by inhibiting the Wnt signaling pathway by promoting E-Cadherin expression and inhibiting the expression of N-Cadherin, ß-Catenin, Vimentin, and Snail. CONCLUSIONS: In conclusion, new four smoking-related genes can be jointly used as prognostic markers for CRC. AKR1B10 served as a tumor suppressor, and can be used as a potential target to inhibit NNK-induced CRC malignant progression by regulating the Wnt signaling pathway. IMPLICATIONS: This study demonstrates that tobacco-derived NNK dependence would promote the malignant progression of colorectal cancer by regulating the expressions of the AKR1B10/Wnt signaling pathway. A novel four-gene signature is established for the prognosis prediction of smoking CRC patients. These findings have important translational implications given the continued use of tobacco and the difficulty in smoking cessation worldwide, which can be applied to alleviate the adverse effects induced by tobacco dependence on colorectal cancer patients.

DNA demethylase TET2-mediated reduction of HADHB expression contributes to cadmium-induced malignant progression of colorectal cancer.

Environmental exposure to the cadmium (Cd) has been shown to be a risk factor for colorectal cancer (CRC) progression, but the exact mechanism has not been fully elucidated. In this study, we found that chronic Cd (3 µM) exposure promoted the proliferation, adhesion, migration, and invasion of CRC cells in vitro, as well as lung metastasis in vivo. RNA-seq and TCGA-COAD datasets revealed that decreased hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit beta (HADHB) expression may be a crucial factor in Cd-induced CRC progression. Further analysis using qRT-PCR and tissue microarrays from CRC patients showed that HADHB expression was significantly reduced in CRC tissues compared to adjacent normal tissues, and low HADHB expression was associated with adverse clinical features and poor overall survival, either directly or through TNM stage. Furthermore, HADHB was found to play an important role in the Cd-induced malignant metastatic phenotype of CRC cells and lung metastasis in mice. Mechanistically, we discovered that chronic Cd exposure resulted in hypermethylation of the HADHB promoter region via inhibition of DNA demethylase tet methylcytosine dioxygenase 2 (TET2), which then led to decreased HADHB expression and activation of the FAK signaling pathway, and ultimately contributed to CRC progression. In conclusion, this study provided a new potential insight and evaluable biomarker for Cd exposure-induced CRC progression and treatment.

Nicotine-derived NNK induces the stemness enrichment of CRC cells through regulating the balance of DUSP4-ERK1/2 feedback loop.

Cigarette smoking has been considered as an independent risk factor for colorectal cancer (CRC) initiation and progression. In this study, we found that cigarette smoking was significantly associated with poor CRC differentiation (P = 0.040). Since studies have indicated that poorly differentiated tumors are more aggressive and metastasize earlier, leading to poorer prognosis; and cancer stem cells (CSCs) are largely responsible for tumor differentiation state, here we observed that the exposure of nicotine-derived 4-(methylnitrosamino)- 1-(3-pyridyl)- 1-butanone (NNK) promoted cell sphere formation and the expression of the stem cell markers, CD44, OCT4, C-MYC and NANOG in HCT8 and DLD-1 cells. Further colony formation assay, CCK-8 assay and tumor-bearing experiment showed that NNK exposure significantly increased the proliferative and growth ability of CRC cells. In mechanism, we found that NNK-activated ERK1/2 played an important role in enrichment of CRC stem cells and the up-regulation of DUSP4, a major negative regulator of ERK1/2. Moreover, DUSP4 up-regulation was essential for maintaining NNK-activated ERK1/2 in an appropriate level, which was an required event for NNK-induced stemness enrichment of CRC cells. Taken together, our findings provided a possible mechanistic insight into cigarette smoking-induced CRC progression.

Reduced expression of annexin A1 promotes gemcitabine and 5-fluorouracil drug resistance of human pancreatic cancer.

Intrinsic chemoresistance is the main reason for the failure of human pancreatic ductal adenocarcinoma (PDAC) therapy. To identify the candidate protein, we compared the protein expression profiling of PDAC cells and its distinct surviving cells following primary treatment with gemcitabine (GEM) and 5-fluorouracil (5-FU) by two-dimensional electrophoresis combined with liquid chromatography-mass spectrometry or mass spectrometry. A total of 20 differentially expressed proteins were identified, and annexin A1 (ANXA1) was analyzed for further validation. The functional validation showed that the downregulation of ANXA1 contributes to GEM and 5-FU resistance in PDAC cells through protein kinase C/c-Jun N-terminal kinase/P-glycoprotein signaling pathway. Our findings provide a platform for the further elucidation of the underlying mechanisms of PDAC intrinsic chemoresistance and demonstrated that ANXA1 may be a valid marker for anticancer drug development.

The expression of Cullin1 is increased in renal cell carcinoma and promotes cancer cell proliferation, migration, and invasion.

Cullin1 (Cul1) is a scaffold protein of the ubiquitin E3 ligase Skp1/Cullin1/Rbx1/F-box protein complex, which ubiquitinates a broad range of proteins involved in cell-cycle progression, signal transduction, and transcription. To investigate the role of Cul1 in the development of renal cell carcinoma (RCC), we evaluated the Cul1 expression by immunohistochemistry using a tissue microarray (TMA) containing 307 cases of RCC tissues and 34 normal renal tissues. The Cul1 expression was increased significantly in RCC and was correlated with renal carcinoma histology grade (P = 0.007), tumor size (P = 0.013), and pT status (P = 0.023). Also, we found that silencing of Cul1 leads to increased expression of p21 and p27 that could inhibit the cyclin D1 and cyclin E2 expressions and arrest cell cycle at the G1 phase. Furthermore, knockdown of Cul1 inhibits RCC cell migration and invasion abilities by up-regulating the expression of TIMP-1 which could inhibit the expression of MMP-9. Finally, using bioluminescence imaging, we found that Cul1 knockdown significantly reduced the tumor growth in vivo. Cul1 may constitute a potential therapeutic target in RCC.

JWA suppresses tumor angiogenesis via Sp1-activated matrix metalloproteinase-2 and its prognostic significance in human gastric cancer.

JWA, a multifunctional microtubule-binding protein, plays an important role in regulating tumor metastasis via inhibition of matrix metalloproteinase-2 (MMP-2). Recent investigations suggest that MMP-2 is an angiogenesis-associated molecule. In this study, we provide novel evidence that JWA inhibits tumor angiogenesis in gastric cancer (GC). In two independent retrospective GC cohorts, we found that the expression of JWA was downregulated and that of MMP-2 was upregulated in GC tissues compared with the same in normal gastric mucosa. For patients treated with surgery alone, a strong and independent negative prognostic value was shown for low JWA and high MMP-2 expressions separately, which was even stronger when combined (hazard ratio = 7.75, P < 0.001, in the training cohort; hazard ratio = 2.31, P < 0.001, in the validation cohort). Moreover, we found that loss of JWA expression was strongly correlated with increased GC angiogenesis. In vitro, JWA inhibited MMP-2 at both messenger RNA and protein levels by modulating Sp1 activity. Knockdown of endogenous JWA resulted in enhanced human umbilical vein endothelial cell tube formation and MMP-2 expression. Furthermore, JWA was found to inhibit Sp1 activity via an ubiquitin-proteasome-dependent mechanism and to downregulate the expression of the proangiogenic MMP-2. Our findings imply that JWA and MMP-2 may serve as promising prognostic markers in resectable GC, with JWA as a useful biomarker of angiogenesis in GC and a potential therapeutic target by MMP-2 modulation.

The prognostic value of CD133 expression in non-small cell lung cancer: a meta-analysis.

CD133 has been identified as a potential cancer stem cell (CSC) marker in non-small cell lung cancer (NSCLC). However, the clinical and prognostic significance of CD133 in NSCLC remains controversial. In this study, a meta-analysis with a total number of 13 studies was performed to clarify the association between CD133 expression and clinical outcomes in publications up to June 2013. Odds ratios (ORs) and their 95 % confidence intervals (CIs) were used to assess the association between CD133 expression and the clinicopathological characteristics of NSCLC. Hazard ratios (HRs) and their 95 % CI were used to quantify the predictive ability of CD133 on NSCLC prognosis. Analysis of these data showed that CD133 expression was not associated with any clinicopathological parameters except for histology (pooled OR = 1.35, 95%CI = 1.04-1.76, P = 0.024) and tumor differentiation (pooled OR = 3.19, 95%CI = 1.10-9.21, P = 0.032). Simultaneously, we also found that positive CD133 expression was not associated with disease-free survival (DFS) (pooled HR = 1.76, 95 % CI = 0.87-3.57, P = 0.114, random-effect) but was associated with overall survival (OS) (pooled HR = 2.06, 95 % CI = 1.08-3.91, P = 0.027, random-effect). Overall, it is appropriate to regard CD133 expression as a potential prognostic factor for the OS of NSCLC patients.

CHIP functions as a novel suppressor of tumour angiogenesis with prognostic significance in human gastric cancer.

OBJECTIVE: CHIP (carboxy terminus of Hsc70 interacting protein) is an E3 ubiquitin ligase that can induce ubiquitination and degradation of several tumour related proteins, and acts as a suppressor of tumour metastasis. This study explored the biological function and clinical significance of CHIP in gastric cancer (GC). METHODS: The prognostic value of CHIP expression was evaluated using tissue microarray and immunohistochemical staining in two independent human GC cohorts. The role of CHIP on tumorigenicity and angiogenesis was determined in vitro and in vivo. RESULTS: CHIP expression was significantly decreased in GC lesions compared with paired non-cancerous tissues. Low tumoral CHIP expression significantly correlated with clinicopathological characteristics in patients, as well as with shorter overall survival in both cohorts. Multivariate Cox regression analysis revealed that CHIP expression was an independent prognostic factor for human GC patients. Moreover, CHIP overexpression impeded the formation of anchorage independent colonies in soft agar, suppressed the growth of xenografts in nude mice and inhibited endothelial cell growth and tube formation by suppressing nuclear factor κB (NF-κB) mediated interleukin 8 (IL-8) expression in vitro. In vivo studies also confirmed that CHIP inhibited blood vessel formation and recruitment of CD31 positive cells in matrigel plugs. Also, CHIP interacted with NF-κB/p65 and promoted its ubiquitination and degradation by proteasome, terminating NF-κB activity and inhibiting IL-8-induced angiogenesis, which correlated with subsequent tumour metastasis. CONCLUSIONS: Decreased CHIP expression in GC resulted in increased angiogenesis and contributed to GC progression and poor prognosis. CHIP expression is a GC candidate clinical prognostic marker and a putative treatment target.

The demethylase ALKBH5 mediates ZKSCAN3 expression through the m6A modification to activate VEGFA transcription and thus participates in MNNG-induced gastric cancer progression.

N-Nitroso compounds (NOCs) are recognized as important factors that promote gastric cancer development, but the specific effects and potential mechanisms by which NOC exposure promotes gastric cancer are still poorly understood. In this study, we explored the effects and potential molecular mechanisms of NOCs on the promotion of gastric cancer using methylnitronitrosoguanidine (MNNG), a classical direct carcinogen of NOC. The results of in vivo and in vitro experiments showed that chronic and low-concentration MNNG exposure significantly promoted the malignant progression of tumors, including cell migration, cell invasion, vasculogenic mimicry (VM) formation, cell spheroid formation, stem cell-like marker expression, and gastric cancer growth and metastasis. Mechanistically, we revealed that demethylase ALKBH5 regulated the level of the N6­methyladenosine (m6A) modification in the 3'UTR and CDS region of the ZKSCAN3 mRNA to promote ZKSCAN3 expression, mediated the binding of ZKSCAN3 to the VEGFA promoter region to regulate VEGFA transcription, and participated in MNNG-induced gastric cancer cell migration, invasion, VM formation, cell spheroid formation, stem cell-like marker expression and ultimately gastric cancer progression. In addition, our study revealed that ALKBH5-ZKSCAN3-VEGFA signaling was significantly activated during MNNG-induced gastric carcinogenesis, and further studies in gastric cancer patients showed that ALKBH5, ZKSCAN3, and VEGFA expression were upregulated in cancers compared with paired gastric mucosal tissues, that ALKBH5, ZKSCAN3, and VEGFA could serve as important biomarkers for determining patient prognosis, and that the molecular combination showed greater prognostic value. These findings provide a theoretical basis for developing gastric cancer interventions for NOCs and for determining gastric cancer progression.

Nicotine-derived NNK promotes CRC progression through activating TMUB1/AKT pathway in METTL14/YTHDF2-mediated m6A manner.

Cigarette smoking substantially promotes tumorigenesis and progression of colorectal cancer; however, the underlying molecular mechanism remains unclear. Among 662 colorectal cancer patients, our investigation revealed a significant correlation between cigarette smoking and factors, such as large tumor size, poor differentiation, and high degree of invasion. Among the nicotine-derived nitrosamines, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) emerged as the most critical carcinogen, which significantly promoted the malignant progression of colorectal cancer both in vivo and in vitro. The results of methylated RNA immunoprecipitation and transcriptome sequencing indicated that NNK upregulated transmembrane and ubiquitin-like domain-containing protein 1 (TMUB1) via N6-adenosine methylation, which was regulated by methyltransferase-like 14 (METTL14) and YTH N6-methyladenosine RNA binding protein 2 (YTHDF2). Elevated TMUB1 levels were associated with a higher risk of cancer invasion and metastasis, leading to a high mortality risk in patients with colorectal cancer. Additionally, TMUB1 promoted lysine63-linked ubiquitination of AKT by interacting with AMFR, which led to the induction of malignant proliferation and metastasis in colorectal cancer cells exposed to NNK. In summary, this study provides a new insight, indicating that targeting TMUB1 expression via METTL14/YTHDF2 mediated N6-adenosine methylation may be a potential therapeutic and prognostic target for patients with colorectal cancer who smoke.

MDM2 is a useful prognostic biomarker for resectable gastric cancer.

Expression of MDM2 protein appears to be increased in malignancy and correlated to prognosis of tumors, but its role in gastric cancer remains controversial. Our recent investigations indicated that JWA was a novel candidate biomarker for gastric cancer. To evaluate the impact of MDM2 protein expression alone, and in combination with JWA, on the prognostic and predictive of patients with resectable gastric cancer, expression of MDM2 and JWA were examined by immunohistochemistry in three large cohorts (total n = 1131) of patient with gastric cancer. We found that MDM2 protein levels were significantly upregulated in gastric cancer (70.4%, 57 of 81) compared with adjacent non-cancerous tissues. High tumoral MDM2 expression significantly correlated with clinicopathologic characteristics, as well as with shorter overall survival (OS; P < 0.001 for all cohorts) in patients without adjuvant treatment. The effect of adjuvant fluorouracil-leucovorin-oxaliplatin (FLO) in improving OS compared with surgery alone was evident only in the high MDM2 group (hazard ratio = 0.57; 95% confidence interval, 0.37-0.89; P = 0.013). Furthermore, knockdown of MDM2 and overexpression of JWA had a synergistic effect on suppression of gastric cancer cell proliferation and migration. Patients with low MDM2 and high JWA expression had a better outcome of survival compared with the other groups (P < 0.001 for all cohorts). For the first time, our data suggest that MDM2 is a potent prognostic and predictive factor for benefit from adjuvant fluorouracil-leucovorin-oxaliplatin chemotherapy in resectable gastric cancer. The combination of MDM2 expression and JWA could serve as a more effective candidate prognostic biomarker for gastric cancer.

Low-dose monobutyl phthalate stimulates steroidogenesis through steroidogenic acute regulatory protein regulated by SF-1, GATA-4 and C/EBP-beta in mouse Leydig tumor cells.

BACKGROUND: The ubiquitous use of dibutyl phthalate (DBP), one of the most widely used plasticizers, results in extensive exposure to humans and the environment. DBP and its major metabolite, monobutyl phthalate (MBP), may alter steroid biosynthesis and their exposure may lead to damage to male reproductive function. Low-doses of DBP/MBP may result in increased steroidogenesis in vitro and in vivo. However, the mechanisms of possible effects of low-dose MBP on steroidogenesis remain unclear. The aim of present study was to elaborate the role of transcription factors and steroidogenic acute regulatory protein in low-dose MBP-induced distruption of steroidogenesis in mouse Leydig tumor cells (MLTC-1 cells). METHODS: In the present study, MLTC-1 cells were cultured in RPMI 1640 medium supplemented with 2 g/L sodium bicarbonate. Progesterone level was examined by I125-pregesterone Coat-A-Count radioimmunoassay (RIA) kits. mRNA and protein levels were assessed by reverse transcription-polymerase chain reaction (RT-PCR) and western blot, respectively. DNA-binding of several transcription factors was examined by electrophoretic mobility shift assay (EMSA). RESULTS: In this study, various doses of MBP (0, 10(-9), 10(-8), 10(-7), or 10(-6) M) were added to the medium followed by stimulation of MLTC-1 cells with human chorionic gonadotrophin (hCG). The results showed that MBP increased progesterone production and steroidogenic acute regulatory protein (StAR) mRNA and protein levels. However, the protein levels of cytochrome P450scc and 3 beta-hydroxy-steroid dehydrogenase (3 beta-HSD) were unchanged after MBP treatment. EMSA assay showed that DNA-binding of steroidogenic factors 1(SF-1), GATA-4 and CCAAT/enhancer binding protein-beta (C/EBP-beta) was increased in a dose-dependent manner after MBP exposure. Western blot tests were next employed and confirmed that the protein levels of SF-1, GATA-4 and C/EBP-beta were also increased. Additionally, western blot tests confirmed the expression of DAX-1, negative factor of SF-1, was dose-dependently down regulated after MBP exposure, which further confirmed the role of SF-1 in MBP-stimulated steroid biosynthesis. CONCLUSIONS: In conclusion, we firstly delineated the regulation of StAR by transcription factors including SF-1, GATA-4 and C/EBP-beta maybe critical mechanism involved in low-dose MBP-stimulated steroidogenesis.

[Retracted] Pin2/TRF1­binding protein X1 inhibits colorectal cancer cell migration and invasion in vitro and metastasis in vivo via the nuclear factor­κB signaling pathway.

Following the publication of the above article, an interested reader drew to the authors' attention that Figs. 3C and E in the paper appeared to contain instances of duplicated data. The authors were able to consult their original data files, and realized that these figures had indeed been assembled incorrectly; subsequently, they requested that a corrigendum be published to take account of the errors that were made during the compilation of these figures. Having investigated this matter in the Editorial Office, however, additional panels of overlapping data were identified, comparing between Figs. 3 and 5; specifically, overlapping data panels were also identified in panels in Figs. 3C, E and F, and 5C and D. The Editor of Oncology Reports has considered the authors' request to publish a corrigendum, but has decided to decline this request on account of the large number of errors that have been identified; rather, the article is to be be retracted from the Journal on the basis of an overall lack of confidence in the presented data. The Editor apologizes to the readership of the Journal for any inconvenience caused. [Oncology Reports 40: 1533­1544, 2018; DOI: 10.3892/or.2018.6570].

Purple Yam Polyphenol Extracts Exert Anticolitis and Anticolitis-Associated Colorectal Cancer Effects through Inactivation of NF-κB/p65 and STAT3 Signaling Pathways.

Colorectal cancer is a malignancy with high incidence and mortality worldwide, and ulcerative colitis (UC) is strongly associated with colorectal cancer. Purple yam, also known as Dioscorea alata, has been reported to be rich in plant polyphenols that have possessed anti-inflammatory, antioxidant, and antitumor properties. However, it is not clear whether purple yam polyphenol extracts (PYPE) can improve colitis and inhibit colitis-related colorectal tumorigenesis. Therefore, we used dextran sulfate sodium (DSS)-induced colitis and azoxymethane (AOM)/DSS-induced colitis-associated colorectal cancer (CAC) models in mice to evaluate the preventive value and possible mechanisms of PYPE. It was found that PYPE effectively alleviated DSS-induced colitis, inhibited macrophage infiltration, and reduced the production of the pro-inflammatory cytokines, such as TNF-α, IL-6, IL-1ß, IL-17A, CXCL1, and MCP-1, and the higher the concentration of PYPE, the better the inhibitory effect. In addition, PYPE dramatically prevented the development of CAC and tumor proliferation in mice. Furthermore, PYPE inactivated NF-κB and STAT3 signaling to exert anti-inflammatory and anticancer effects. Taken together, these findings indicate that PYPE may be used as a promising preventive strategy against UC and CAC.

Sesamin inhibits hypoxia-stimulated angiogenesis via the NF-κB p65/HIF-1α/VEGFA signaling pathway in human colorectal cancer.

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths. Tumor angiogenesis plays a critical role in CRC metastasis, and hypoxia, which widely existed in the tumor mass, drives tumor angiogenesis. Sesamin, a phytochemical derived from sesame seeds, has been reported to inhibit tumor cell growth and metastasis, however, the role of sesamin in CRC angiogenesis and its underlying mechanism have not been investigated yet. Here, an in vitro tube formation assay and an in vivo angiogenesis assay were used to explore the role of sesamin in CRC angiogenesis. In this study, we found that sesamin significantly inhibited hypoxia-stimulated CRC angiogenesis in a dose-dependent manner in vitro. Moreover, oral intake of sesamin dramatically suppressed neovessel formation of matrigel plugs with CRC cells in nude mice. In mechanism, sesamin reduced the expression of VEGFA to inhibit hypoxia-induced CRC angiogenesis. In addition, sesamin inhibited the phosphorylation of IκBα and thus restrained NF-κB p65 to activate HIF-1α transcription under hypoxic conditions. Finally, our results indicated that sesamin inhibited hypoxia-induced CRC angiogenesis via the NF-κB/HIF-1α/VEGFA signaling pathway. Our study might provide a theoretical and experimental basis for the use of sesamin in the prevention and treatment of CRC.

Identification and validation of a cigarette smoke-related five-gene signature as a prognostic biomarker in kidney renal clear cell carcinoma.

Cigarette smoking greatly promotes the progression of kidney renal clear cell carcinoma (KIRC), however, the underlying molecular events has not been fully established. In this study, RCC cells were exposed to the tobacco specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, nicotine-derived nitrosamine) for 120 days (40 passages), and then the soft agar colony formation, wound healing and transwell assays were used to explore characteristics of RCC cells. RNA-seq was used to explore differentially expressed genes. We found that NNK promoted RCC cell growth and migration in a dose-dependent manner, and RNA-seq explored 14 differentially expressed genes. In TCGA-KIRC cohort, Lasso regression and multivariate COX regression models screened and constructed a five-gene signature containing ANKRD1, CYB5A, ECHDC3, MT1E, and AKT1S1. This novel gene signature significantly associated with TNM stage, invasion depth, metastasis, and tumor grade. Moreover, when compared with individual genes, the gene signature contained a higher hazard ratio and therefore had a more powerful value for the prognosis of KIRC. A nomogram was also developed based on clinical features and the gene signature, which showed good application. Finally, AKT1S1, the most crucial component of the gene signature, was significantly induced after NNK exposure and its related AKT/mTOR signaling pathway was dramatically activated. Our findings supported that NNK exposure would promote the KIRC progression, and the novel cigarette smoke-related five-gene signature might serve as a highly efficient biomarker to identify progression of KIRC patients, AKT1S1 might play an important role in cigarette smoke exposure-induced KIRC progression.

Erratum: TRIM59 Is a Novel Marker of Poor Prognosis and Promotes Malignant Progression of Ovarian Cancer by Inducing Annexin A2 Expression : Erratum.

[This corrects the article DOI: 10.7150/ijbs.28757.].

ING4 Promotes Stemness Enrichment of Human Renal Cell Carcinoma Cells Through Inhibiting DUSP4 Expression to Activate the p38 MAPK/type I IFN-Stimulated Gene Signaling Pathway.

Renal cell carcinoma (RCC) recurs frequently due to high metastatic spread, resulting in a high mortality. Cancer stem cells play a critical role in initiating the tumor metastasis. Inhibitor of growth 4 (ING4) is a member of the ING family, but its impact on cancer stem cells in RCC is still unknown. In this study, we found that ING4 significantly promoted the sphere-forming size and number of RCC cells under an ultralow-attachment culture condition in vitro, tumor growth and metastasis in vivo, and the expression of some stem-like or pluripotent biomarkers CD44, MYC, OCT4, and NANOG, indicating that ING4 increased the stemness enrichment of RCC cells. Mechanistically, the ING4-activated p38 MAPK pathway possibly upregulated the expression of type I IFN-stimulated genes to promote the formation of RCC stem cells. ING4 could inhibit the expression of DUSP4 to activate p38 MAPK. In addition, selective pharmacological p38 MAPK inhibitors could significantly inhibit stemness enrichment only in ING4-overexpressed RCC cells, suggesting that the p38 MAPK inhibitors might be effective in patients with high ING4 expression in RCC tissue. Taken together, our findings proposed that ING4 might serve as a potential therapeutic target for metastatic RCC, particularly RCC stem cells.

miR­3133 inhibits proliferation and angiogenesis by targeting the JUNB/VEGF pathway in human umbilical vein endothelial cells.

Membranous obstruction of the inferior vena cava (MOVC) has the highest incidence rate among the different types of Budd­Chiari syndrome (BCS) in China. The inferior vena cava septum of patients with MOVC contains capillaries and the two surfaces of the membrane are composed of vascular endothelial tissue. Membrane formation occurs due to endothelial damage. MicroRNAs (miRNAs/miRs) have been verified to be involved in the pathogenesis and progression of various human diseases. A previous study by our group suggested that miR­3133 was downregulated in the serum of patients with MOVC. In the present study, the possible mechanistic implication of miR­3133 in MOVC­associated processes was further explored. It was observed that miR­3133 overexpression inhibited, whereas miR­3133 knockdown enhanced the proliferation and tube formation of human umbilical vein endothelial cells (HUVECs) using the CCK­8 and tube formation assays. JUNB, a member of activator protein 1 and an important upstream transcriptional molecule of vascular endothelial growth factor (VEGF), was proven to be a direct target gene of miR­3133 using a bioinformatics prediction and luciferase reporter assay. Meanwhile, the mRNA and protein expression of JUNB and VEGF was determined by PCR, ELISA and western blot analyses. Of note, miR­3133 overexpression downregulated, while miR­3133 knockdown elevated the expression of JUNB and VEGF significantly. Furthermore, it was demonstrated that JUNB upregulated the expression and secretion of VEGF to promote HUVEC proliferation and angiogenesis. miR­3133 was able to inhibit the effect of JUNB overexpression to promote cell proliferation, angiogenesis and the expression of VEGF. In conclusion, the present study demonstrated that miR­3133 regulated endothelial cell proliferation and angiogenesis through the JUNB/VEGF pathway, which may provide an approach for inhibiting diaphragm formation of the inferior vena cava in MOVC.

PTBP3 contributes to colorectal cancer growth and metastasis via translational activation of HIF-1α.

BACKGROUND: Colorectal cancer (CRC) remains the fourth most common cause of cancer-related mortality worldwide. We aimed to identify key molecules and signalling pathways mediating CRC growth and metastasis. Polypyrimidine tract-binding protein 3 (PTBP3) is a member of PTB family. A prooncogenic role for PTBP3 has also been discovered in several kinds of tumors. However, the expression and biological functions of the PTBP3 are still unknown in CRC. METHODS: We analysed the expression levels of PTBP3 using tissue microarray containing 568 CRC tissues and corresponding non-tumor adjacent tissues. The correlations between the PTBP3 expression level and clinicopathological features were evaluated using the chi-square test. The functional characterization for the role and molecular mechanism of PTBP3 in CRC was investigated through a series of in vitro and in vivo experiments. RESULTS: We showed that PTBP3 expression was increased in human CRC, and high PTBP3 expression was correlated with poor five-year overall survival and disease-free survival. Moreover, PTBP3 promoted tumor cell proliferation, migration and invasion in vitro and tumor growth and metastasis in vivo. PTBP3 enhanced HIF-1α protein expression by directly binding to the 5'UTR HIF-1α mRNA and activated translation of HIF-1α. Furthermore, HIF-1α was responsible for PTBP3-induced cell migration and invasion. CONCLUSIONS: PTBP3 appears to be a novel oncogene of CRC through binding to the IRES region of HIF-1α mRNA, which regulates HIF-1α translation. PTBP3 can serve as a promising predictive biomarker for recurrence and prognosis in patients with CRC.