MicroRNA-23a-3p influences the molecular mechanism of gastric cancer cells via CCL22/PI3K/Akt axis.

A great many microRNAs (miRNAs) have been reported to play different roles in human cancers, including gastric cancer (GC). However, the specific character of miR-23a-3p in GC has not been elucidated. This study was to explore the function of miR-23a-3p in GC. The results manifested that miR-23a-3p was down-regulated in GC and patients with reduced miR-23a-3p had poor prognosis. Functional experiments assured that elevated miR-23a-3p refrained GC proliferation, invasion, migration, PIK3/Akt phosphorylation and apoptosis, while knockdown miR-23a-3p accelerated the growth of GC. Double luciferase report experiments manifested that miR-23a-3p targeted CCL22 expression. Functional rescue experiments affirmed that the repression of elevated miR-23a-3p on GC was reversed by simultaneous augmented CCL22. In vivo, elevated miR-23a-3p restrained the volume and tumor of GC and reduced the expression of CCL22 and phosphorylated PIK3/Akt, while knockdown miR-23a-3p motivated tumor growth. In conclusion, the results of this study indicate that miR-23a-3p plays a repressive role in GC, and affects the progression of GC via down-regulating CCL22 and blocking PI3K/AKT signal transduction pathway, which may offer a new molecular target for clinical treatment of GC.

Integrative molecular characterization of Chinese prostate cancer specimens.

Prostate cancer (PCa) exhibits epidemiological and molecular heterogeneity. Despite extensive studies of its phenotypic and genetic properties in Western populations, its molecular basis is not clear in Chinese patients. To determine critical molecular characteristics and explore correlations between genomic markers and clinical parameters in Chinese populations, we applied an integrative genetic/transcriptomic assay that combines targeted next-generation sequencing and quantitative real-time PCR (qRT-PCR) on samples from 46 Chinese patients with PCa. Lysine (K)-specific methyltransferase 2D (KMT2D), zinc finger homeobox 3 (ZFHX3), A-kinase anchoring protein 9 (AKAP9), and GLI family zinc finger 1 (GLI1) were frequently mutated in our cohort. Moreover, a clinicopathological analysis showed that RB transcriptional corepressor 1 (RB1) deletion was common in patients with a high risk of disease progression. Remarkably, four genomic events, MYC proto-oncogene (MYC) amplification, RB1 deletion, APC regulator of WNT signaling pathway (APC) mutation or deletion, and cyclin-dependent kinase 12 (CDK12) mutation, were correlated with poor disease-free survival. In addition, a close link between KMT2D expression and the androgen receptor (AR) signaling pathway was observed both in our cohort and in The Cancer Genome Atlas Prostate Adenocarcinoma (TCGA-PRAD) data. In summary, our results demonstrate the feasibility and benefits of integrative molecular characterization of PCa samples in disease pathology research and personalized medicine.

Air pollutants and outpatient visits for cardiovascular disease in a severe haze-fog city: Shijiazhuang, China.

BACKGROUND: Many studies have reported the impact of air pollution on cardiovascular disease (CVD), but few of these studies were conducted in severe haze-fog areas. The present study focuses on the impact of different air pollutant concentrations on daily CVD outpatient visits in a severe haze-fog city. METHODS: Data regarding daily air pollutants and outpatient visits for CVD in 2013 were collected, and the association between six pollutants and CVD outpatient visits was explored using the least squares mean (LSmeans) and logistic regression. Adjustments were made for days of the week, months, air temperature and relative humidity. RESULTS: The daily CVD outpatient visits for particulate matter (PM10 and PM2.5), sulphur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) in the 90th-quantile group were increased by 30.01, 29.42, 17.68, 14.98, 29.34%, and - 19.87%, respectively, compared to those in the <10th-quantile group. Odds ratios (ORs) and 95% confidence intervals (CIs) for the increase in daily CVD outpatient visits in PM10 300- and 500-µg/m3, PM2.5 100- and 300-µg/m3 and CO 3-mg/m3 groups were 2.538 (1.070-6.020), 7.781 (1.681-36.024), 3.298 (1.559-6.976), 8.72 (1.523-49.934), and 5.808 (1.016-33.217), respectively, and their corresponding attributable risk percentages (AR%) were 60.6, 87.15, 69.68, 88.53 and 82.78%, respectively. The strongest associations for PM10, PM2.5 and CO were found only in lag 0 and lag 1. The ORs for the increase in CVD outpatient visits per increase in different units of the six pollutants were also analysed. CONCLUSIONS: All five air pollutants except O3 were positively associated with the increase in daily CVD outpatient visits in lag 0. The high concentrations of PM10, PM2.5 and CO heightened not only the percentage but also the risk of increased daily CVD outpatient visits. PM10, PM2.5 and CO may be the main factors of CVD outpatient visits.

Loss of KMT2D induces prostate cancer ROS-mediated DNA damage by suppressing the enhancer activity and DNA binding of antioxidant transcription factor FOXO3.

Histone methyltransferase KMT2D has diverse functions and distinct mechanisms in different cancers. Although we have previously found KMT2D serves as an oncogene that promotes tumor growth and metastasis in prostate cancer (PCa), the functions and mechanisms of KMT2D are complicated and most remain undefined. Here, the function of KMT2D regarding DNA damage in PCa and the underlying mechanisms of KMT2D in epigenetic regulation were explored in a series of studies. Knockdown of KMT2D sensitized cells to DNA damage through the disturbance of antioxidative gene expression and increased levels of intracellular reactive oxygen species, which led to cell apoptosis and senescence. The loss of KMT2D reduced the abundance of enhancer activity markers H3K4me1 and H3K27ac, which blocked the DNA binding of FOXO3, a critical mediator of the cellular response to oxidative stress, and suppressed antioxidative gene transcription. Moreover, KMT2D deletion in PCa cells also increased their sensitivity to genotoxic anticancer drugs and a PARP inhibitor, which suggested that lower levels of KMT2D may mediate the response of PCa to particular treatments. These findings further highlighted the important role of KMT2D in PCa progression and suggested that targeting KMT2D might be therapeutically beneficial for advanced PCa treatment.

Correction: Regulation of tumor suppressor EAF2 polyubiquitination by ELL1 and SIAH2 in prostate cancer cells.

[This corrects the article DOI: 10.18632/oncotarget.8588.].

Regulation of ELL2 stability and polyubiquitination by EAF2 in prostate cancer cells.

BACKGROUND: Elongation factor for RNA polymerase 2 (ELL2) and ELL associated factor 2 (EAF2) have been reported to have tumor suppressive properties in prostate epithelial cells. AIMS: We investigated ELL2 expression in human prostate cancer specimens, and ELL2 protein stability and ubiquitination in prostate cancer cells. MATERIALS AND METHODS: Immunostaining analysis of human prostate cancer specimens was used to determine ELL2 expression in tumor and normal tissues. ELL2 knockdown in prostate cancer cell lines LNCaP and C4-2 was used to compare proliferation and motility. Deletion and site-directed mutagenesis was used to identify amino acid residues in ELL2 that were important for degradation. RESULTS: ELL2 protein was downregulated in prostate cancer specimens and was up-regulated by androgens in prostate cancer cell lines LNCaP and C4-2. ELL2 knockdown enhanced prostate cancer cell proliferation and motility. ELL2 protein has a short half-life and was stabilized by proteasome inhibitor MG132. Amino acid residues K584 and K599 in ELL2 were important for ELL2 degradation. EAF2 could stabilize ELL2 and inhibited its polyubiquitination. CONCLUSION: Our findings provide further evidence that ELL2 is a potential tumor suppressor frequently down-regulated in clinical prostate cancer specimens and provides new insights into regulation of ELL2 protein level by polyubiquitination and EAF2 binding.

XB130 is overexpressed in prostate cancer and involved in cell growth and invasion.

XB130 is a cytosolic adaptor protein involved in various physiological processes and oncogenesis of certain malignancies, but its role in the development of prostate cancer remains unclear. In current study, we examined XB130 expression in prostate cancer tissues and found that XB130 expression was remarkably increased in prostate cancer tissues and significantly correlated with increased prostate specific antigen (PSA), free PSA (f-PSA), prostatic acid phosphatase (PAP) and T classification. Patients with highly expressed XB130 had significantly decreased survival, which suggested XB130 as a possible prognostic indicator for prostate cancer. In vitro experiments showed that reduced XB130 expression restrained tumor growth both in vitro and in vivo. Furthermore, XB130 knockdown hindered transition of G1 to S phase in prostate cancer cell line DU145 and LNCap, which might contribute to the inhibition of cellular proliferation. Results from transwell assay demonstrated that downregulation of XB130 may attenuate invasion and metastasis of prostate cancer. Semiquantitative analysis of Western blot suggested that decreased XB130 expression was accompanied by diminished Akt signaling and EMT process. Thus, above observations suggest that XB130 may be a novel molecular marker and potent therapeutic target for prostate cancer.

Regulation of tumor suppressor EAF2 polyubiquitination by ELL1 and SIAH2 in prostate cancer cells.

RNA Polymerase II Elongation Factor (ELL)-associated factor 2 (EAF2) is a tumor suppressor frequently down-regulated in human prostate cancer. We previously reported that its binding partner ELL1 can enhance EAF2 protein stability and activity. Here we show that EAF2 can be polyubiquitinated and its degradation blocked by proteasome inhibitor. Co-immunoprecipitation detected EAF2 binding to SIAH2, an E3 ligase, and SIAH2 overexpression enhanced polyubiquitination of EAF2. Co-transfection of EAF2 binding partner ELL1 blocked EAF2 ubiquitination, providing a mechanism for EAF2 stabilization. Finally, EAF2K81R mutant, which exhibits reduced polyubiquitination and increased stability, was more potent than wild-type EAF2 in apoptosis induction. These findings suggest that SIAH2 is an E3 ligase for EAF2 polyubiquitination and ELL1 can enhance EAF2 level and function by blocking its polyubiquitination.

Pristimerin overcomes adriamycin resistance in breast cancer cells through suppressing Akt signaling.

Breast cancer remains a major public health problem worldwide. Chemotherapy serves an important role in the treatment of breast cancer. However, resistance to chemotherapeutic agents, in particular, multi-drug resistance (MDR), is a major cause of treatment failure in cancer. Agents that can either enhance the effects of chemotherapeutics or overcome chemoresistance are urgently needed for the treatment of breast cancer. Pristimerin, a quinonemethide triterpenoid compound isolated from Celastraceae and Hippocrateaceae, has been shown to possess antitumor, anti-inflammatory, antioxidant and insecticidal properties. The aim of the present study was to investigate whether pristimerin can override chemoresistance in MCF-7/adriamycin (ADR)-resistant human breast cancer cells. The results demonstrated that pristimerin indeed displayed potent cytocidal effect on multidrug-resistant MCF-7/ADR breast cancer cells, and that these effects occurred through the suppression of Akt signaling, which in turn led to the downregulation of antiapoptotic effectors and increased apoptosis. These findings indicate that use of pristimerin may represent a potentially promising approach for the treatment of ADR-resistant breast cancer.

Inhibition of mTOR sensitizes breast cancer stem cells to radiation-induced repression of self-renewal through the regulation of MnSOD and Akt.

The sensitization of breast cancer stem cells (BrCSCs) to the inhibitive effects of radiotherapy through adjuvant therapy which targets oncogenic pathways represents a prospective strategy for improving the effect of radiation in patients with triple-negative breast cancer (TNBC). Mammalian target of rapamycin (mTOR) activation is one of the most frequent events in human malignancies, and is critical for sustaining the self­renewing ability of cancer stem cells (CSCs); inhibition by rapamycin is an effective and promising strategy in anticancer treatments. In the present study, we found that mTOR activity was closely related to the self-renewal ability of BrCSCs, and in triple negative MDA-MB-453 and MDA-MB­468 cells, rapamycin repression of mTOR phosphorylation decreased the number of mammospheres and helped to sensitize the resistant CSCs to low-dose radiation therapy. By inhibiting mTOR and mitochondrial manganese superoxide dismutase (MnSOD), we confirmed that rapamycin functioned through the mTOR/MnSOD/reactive oxygen species (ROS) signaling pathway, and the existence of Akt governed the rapamycin­induced asymmetric division (AD) of stem cells in cases of radiation­treated breast cancer. The synergic effects of rapamycin and low-dose radiation induced the AD of stem cells, which then resulted in a decrease in the number of mammospheres, and both were mediated by MnSOD. Governed by Akt, the consequent inhibition of ROS formation and oxidative stress preserved the AD mode of stem cells, which is critical for an improved radiotherapy response in clinical treatment, as the tumor group is thus easier to eliminate with radiation therapy. We posit that an in-depth understanding of the interaction of radiation with CSCs has enormous potential and will make radiation even better and more effective.

miR-141 regulates TGF-ß1-induced epithelial-mesenchymal transition through repression of HIPK2 expression in renal tubular epithelial cells.

Epithelial-mesenchymal transition (EMT) plays a critical role in embryonic development, wound healing, tissue regeneration, cancer progression and organ fibrosis. The proximal tubular epithelial cells undergo EMT, resulting in matrix-producing fibroblasts and thereby contribute to the pathogenesis of renal fibrosis. The profibrotic cytokine, TGF­ß, is now recognized as the main pathogenic driver that has been shown to induce EMT in tubular epithelial cells. Increasing evidence indicate that HIPK2 dysfunction may play a role in fibroblasts behavior, and therefore, HIPK2 may be considered as a novel potential target for anti-fibrosis therapy. Recently, members of the miR-200 family (miR­200a, b and c and miR­141) have been shown to inhibit EMT. However, the steps of the multifactorial renal fibrosis progression that these miRNAs regulate, particularly miR­141, are unclear. To study the functional importance of miR­141 in EMT, a well­established in vitro EMT assay was used to demonstrate renal tubulointerstitial fibrosis; transforming growth factor­ß1­induced EMT in HK-2 cells. Overexpression of miR­141 in HK­2 cells, either with or without TGF­ß1 treatment, hindered EMT by enhancing E­cadherin and decreasing vimentin and fibroblast­specific protein 1 expression. miR­141 expression was repressed during EMT in a dose­ and time­dependent manner through upregulation of HIPK2 expression. Ectopic expression of HIPK2 promoted EMT by decreasing E-cadherin. Furthermore, co-transfection of miR­141 with the HIPK2 ORF clone partially inhibited EMT by restoring E­cadherin expression. miR­141 downregulated the expression of HIPK2 via direct interaction with the 3'-untranslated region of HIPK2. Taken together, these findings aid in the understanding of the role and mechanism of miR­141 in regulating renal fibrosis via the TGF­ß1/miR-141/HIPK2/EMT axis, and miR-141 may represent novel biomarkers and therapeutic targets in the treatment of renal fibrosis.

Curcumin protects intestinal mucosal barrier function of rat enteritis via activation of MKP-1 and attenuation of p38 and NF-κB activation.

BACKGROUND: Intestinal mucosa barrier (IMB) dysfunction results in many notorious diseases for which there are currently few effective treatments. We studied curcumin's protective effect on IMB and examined its mechanism by using methotrexate (MTX) induced rat enteritis model and lipopolysaccharide (LPS) treated cell death model. METHODOLOGY/PRINCIPAL FINDINGS: Curcumin was intragastrically administrated from the first day, models were made for 7 days. Cells were treated with curcumin for 30 min before exposure to LPS. Rat intestinal mucosa was collected for evaluation of pathological changes. We detected the activities of D-lactate and diamine oxidase (DAO) according to previous research and measured the levels of myeloperoxidase (MPO) and superoxide dismutase (SOD) by colorimetric method. Intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß) were determined by RT-PCR and IL-10 production was determined by ELISA. We found Curcumin decreased the levels of D-lactate, DAO, MPO, ICAM-1, IL-1ß and TNF-α, but increased the levels of IL-10 and SOD in rat models. We further confirmed mitogen-activated protein kinase phosphatase-1 (MKP-1) was activated but phospho-p38 was inhibited by curcumin by western blot assay. Finally, NF-κB translocation was monitored by immunofluorescent staining. We showed that curcumin repressed I-κB and interfered with the translocation of NF-κB into nucleus. CONCLUSIONS/SIGNIFICANCE: The effect of curcumin is mediated by the MKP-1-dependent inactivation of p38 and inhibition of NF-κB-mediated transcription. Curcumin, with anti-inflammatory and anti-oxidant activities may be used as an effective reagent for protecting intestinal mucosa barrier and other related intestinal diseases.

Soluble intercellular adhesion molecule-1, D-lactate and diamine oxidase in patients with inflammatory bowel disease.

AIM: To study the levels of serum soluble intercellular adhesion molecule-1 (sICAM-1), plasma D-lactate and diamine oxidase (DAO) in patients with inflammatory bowel disease (IBD), and the potential clinical significance. METHODS: Sixty-nine patients with IBD and 30 healthy controls were included in this study. The concentration of sICAM-1 was detected with enzyme-linked immunosorbent assay, the level of D-lactate and DAO was measured by spectroscopic analysis, and the number of white blood cells (WBC) was determined by routine procedure. RESULTS: The levels of sICAM-l, DAO, and WBC in IBD patients were significantly higher than those in the control group (P < 0.01). sICAM-l in IBD patients was found to be closely related to the levels of DAO and D-lactate (212.94 +/- 69.89 vs 6.35 +/- 2.35, P = 0.000), DAO 212.94 +/- 69.89 vs 8.65 +/- 3.54, P = 0.000) and WBC (212.94 +/- 69.89 vs 7.40 +/- 2.61, P = 0.000), but no significant difference was observed between patients with ulcerative colitis and patients with Crohn's disease. The post-treatment levels of sICAM-l, D-lactate and WBC were significantly lower than before treatment (sICAM-l 206.57 +/- 79.21 vs 146.21 +/- 64.43, P = 0.000), (D-lactate 1.46 +/- 0.94 vs 0.52 +/- 0.32, P = 0.000) and (WBC 7.24 +/- 0.2.33 vs 5.21 +/- 3.21, P = 0.000). CONCLUSION: sICAM-1, D-lactate and DAO are closely related to the specific conditions of IBD, and thus could be used as a major diagnostic index.

[Changyanqing decoction produces anti-inflammatory effect by inhibiting the activation of nuclear factor-kappaB].

OBJECTIVE: To detect the changes in intestinal mucosal permeation in rats with methotrexate-induced small intestinal damage and investigate the protective effects of Changyanqing decoction. METHODS: Rat enteritis model was established by methotrexate (MTX) and sodium chloride. The rats were randomly divided into normal control group, model group, N-acetylcysteine (NAC) group and Changyanqing decoction group, and Changyanqing decoction (100 mg/kg) or saline was administered daily in the corresponding groups by gastric irrigation for 6 days. The disease activity index (DAI), colonic mucosal damage index (CMDI) and histological score (HS) of the rats were observed and evaluated. The levels of mRNA expressions of TNF-alpha and IL-1beta were detected by semi-quantitative RT-PCR. The expression of IL-10 was detected by enzyme linked immunosorbent assay, and IkappaB expression was determined with Western blotting. RESULTS: Compared with the normal control group, the model group showed significantly increased DAI, CMDI and HS. The DAI, CMDI, and HS in rats treated with Changyanqing decoction were significantly decreased in comparison with those in the model group (P<0.01). The expressions of TNF-alpha and IL-1beta were significantly higher in MTX-treated group than in the control group. The expression of TNF-alpha and IL-1beta mRNA in the Changyanqing group and NAC group were significantly lower, but IL-10 significantly higher than those of the MTX group. In MTX group, obvious NF-kappaB activation was observed, whose expression was significantly stronger in the cell nuclei, and the IkappaB in the cytoplasm was markedly degraded. CONCLUSION: Changyanqing decoction offers protection on intestinal mucosa by inhibiting NF-kappaB activation to reduce TNF-alpha and IL-1beta mRNA expressions and increase IL-10 expression.

[Value of prostate specific antigen in early diagnosis of prostatic cancer].

OBJECTIVE: To evaluate the value of serum prostate specific antigen (PSA), free PSA (FPSA) and PSA density (PSAD) in early diagnosis of prostatic cancer. METHODS: Sixty-eight patients with benign prostate hyperplasia (BPH), 28 with prostatic intraepithelial neoplasia (PIN) without canceration, and 32 with prostatic cancer, all diagnosed by prostatic biopsy, were enrolled in this study. Serum PSA and FPSA were measured and FPSA/PSA ratio and PSAD calculated for each patient, and the data analyzed to explore the association of these indices with prostatic cancer. RESULTS: Serum PSA level and PSAD were markedly different between the cancer patients and non-cancer patients (P<0.001 and P<0.01, respectively). FPSA/PSA ratio also differed between them (P<0.05). The same results were also found between BPH and cancer patients. Significant difference was noted in serum PSA and PSAD between PIN and cancer patients (P<0.01), but not in FPSA/PSA ratio (P>0.05). No marked difference was observed in serum PSA, FPSA/PSA ratio and PSAD between BPH and PIN patients. CONCLUSION: Serum PSA provides a very important clue for early diagnosis of prostatic cancer, and more accurate diagnosis can be obtained by considering also FPSA/PSA ratio. PSAD may also assist in the early diagnosis of prostatic cancer.

[Frequencies of CGT52TGT, GGC54GAC and GGA57GAA point mutations in MBL gene in Chinese Uyghur population].

OBJECTIVE: To investigate the frequencies of three point mutations, CGT52TGT, GGC54GAC and GGA57GAA, in exon 1 of mannan-binding lectin (MBL) structural gene in Chinese Uyghur population. METHODS: Blood samples were collected from a Uyghur population in Xinjiang Uyghur Autonomous Region, and the genomic DNA was extracted from the leucocytes and the target gene fragment amplified by PCR. The three point mutations in exon 1 of MBL gene were detected by fluorogenic probe hybridization technique with visual monitoring. RESULTS: In 95 Uyghur individuals, 2 were identified as homozygous for codon 54 mutations, 28 were heterozygous for codon 54 mutation, and no CGT52TGT and GGA57GAA point mutations were found. CONCLUSION: The frequencies of CGT52TGT, GGC54GAC and GGA57GAA mutant alleles in exon 1 of MBL structural gene are 0, 0.168 and 0 respectively in the Chinese Uyghur population.

[Construction of standard recombinant plasmids for 7 common mannan-binding lectin gene haplotypes].

OBJECTIVE: To construct the standard recombinant plasmids for 7 common haplotypes of mannan-binding lectin (MBL) gene. METHODS: The DNA samples with known haplotypes and genotypes of MBL gene were used as the templates for amplifying the fragments of MBL gene haplotypes including the promoter region and exon 1 with sequence-specific primer-polymerase chain reaction (SSP-PCR) method. The amplified fragments were cloned into T vector and the bases located at codon 52 and codon 57 of exon 1 in MBL gene were mutated respectively by site-directed mutagenesis. All the 7 recombinant plasmids were identified by PCR and direct sequence analysis. RESULTS: From the DNA samples with known haplotypes and genotypes of MBL gene, the standard plasmids of haplotypes HYPA, LXPA, LYQA, LYPA and LYPB of MBL gene were constructed by SSP-PCR and molecular cloning technique. From the recombinant plasmids of HYPA and LYQA, the standard plasmids of haplotypes HYPD and LYQC of MBL gene were constructed by site-directed mutagenesis, respectively. CONCLUSION: The constructed standard plasmids of haplotypes HYPA, LXPA, LYQA, LYPA, LYPB, HYPD and LYQC of MBL gene provide standard controls for detecting the SNPs, haplotypes and genotypes of MBL gene with such genotyping methods us SSP-PCR and real-time PCR.

Molecular cloning and characterization of mannan binding lectin C gene from Balb/c mice.

OBJECTIVE: To obtain full-length cDNA encoding mouse mannan-binding lectin C(MBL-C) polypeptide. METHODS: The cDNA encoding mouse MBL-C was isolated from Balb/c mouse liver cells by reverse transcriptase (RT)-PCR and inserted into pUC-T vector, and the encoding region structure of the DNA was analyzed to understand its evolutionary relationship with single human MBL homologues. RESULTS: The amplified mouse MBL-C cDNA, which was 735 bp in length, encoded 245 amino acid residues, and its structural analysis showed 100% homology with published mouse MBL-C gene sequence and 71.4% homology with MBL gene of Chinese human. CONCLUSION: The gene encoding Balb/c mouse MBL-C has been successfully isolated, which may facilitate further study of the innate immune functions of MBL molecule in vivo.