Circ_0060531 knockdown ameliorates IL-22-induced keratinocyte damage by binding to miR-330-5p to decrease GAB1 expression

BACKGROUND

Psoriasis is a chronic immune-mediated skin disease. Recent studies showed its pathogenesis involved circular RNA (circRNA). However, the role of circ_0060531 in psoriasis development and the behind mechanism remain to be explored.

METHODS

Psoriasis cell model was constructed by treating keratinocytes (HaCaT cells) using interleukin 22 (IL-22). Expression of circ_0060531, microRNA-330-5p (miR-330-5p) and GRB2 associated binder 1 (GAB1) was determined by quantitative real-time polymerase chain reaction. The functional effects of circ_0060531 on IL-22-caused cell injury were investigated by 3-(4,5-Dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide, 5-Ethynyl-29-deoxyuridine, wound-healing and enzyme-linked immunosorbent assays. Protein expression was analysed by Western blot. The interactions among circ_0060531, miR-330-5p and GAB1 were identified by dual-luciferase reporter or RNA immunoprecipitation assay.

RESULTS

Circ_0060531 and GAB1 expression were significantly increased, while miR-330-5p was decreased in psoriatic skin biopsies and IL-22-stimulated HaCaT cells in comparison with controls. In function, circ_0060531 knockdown assuaged IL-22-induced cell proliferation, cell migration and inflammation. Besides, circ_0060531 acted as a miR-330-5p sponge, and regulated the processes of IL-22-treated HaCaT cells by binding to the miRNA. Under the treatment of IL-22, miR-330-5p mediated HaCaT cell damage by targeting GAB1. Importantly, circ_0060531 modulated GAB1 production by interacting with miR-330-5p.

CONCLUSION

Circ_0060531 knockdown assuaged IL-22-induced keratinocyte dysfunction through miR-330-5p/GAB1 pathway, proving a novel target for the therapy of psoriasis.

Disuse muscle atrophy-improving effect of ninjin'yoeito in a mouse model

Disuse syndrome indicates psychosomatic hypofunction caused by excess rest and motionless and muscle atrophy is termed disuse muscle atrophy. Disuse muscle atrophy-induced muscle weakness and hypoactivity further induces muscle atrophy, leading to a vicious cycle, and this is considered a factor causing secondary sarcopenia and subsequently frailty. Since frailty finally leads to a bedridden state requiring nursing, in facing a super-aging society, intervention for a risk factor of frailty, disuse muscle atrophy, is important. However, the main treatment of disuse muscle atrophy is physical therapy and there are fewer effective preventive and therapeutic drugs. The objective of this study was to search for Kampo medicine with a disuse muscle atrophy-improving effect. Ninjin'yoeito is classified as a qi-blood sohozai (dual supplement) in Chinese herbal medicine, and it has an action supplementing the spleen related to muscle. In addition, improvement of muscle mass and muscle weakness by ninjin'yoeito in a clinical study has been reported. In this study, the effect of ninjin'yoeito on disuse muscle atrophy was investigated. A disuse muscle atrophy model was prepared using male ICR mice. After surgery applying a ring for tail suspension, a 1-week recovery period was set. Ninjin'yoeito was administered by mixing it in the diet for 1 week after the recovery period, followed by tail suspension for 14 days. Ninjin'yoeito administration was continued until autopsy including the hindlimb suspension period. The mice were euthanized and autopsied immediately after completion of tail suspension, and the hindlimb muscles were collected. The food and water intakes during the hindlimb unloaded period, wet weight of the collected muscle, and muscle synthesis and muscle degradation-related factors in blood and muscle were evaluated. Ingestion of ninjin'yoeito inhibited tail suspension-induced reduction of the soleus muscle wet weight. In addition, an increase in the blood level of a muscle synthesis-related factor, IGF-1, and promotion of phosphorylation of mTOR and 4E-BP1 in the soleus muscle were observed. It was suggested that ninjin'yoeito has a disuse muscle atrophy-improving action. Promotion of the muscle synthesis pathway was considered the action mechanism of this.

MiR-145 regulates steroidogenesis in mouse primary granulosa cells through targeting Crkl

AIMS

It has been demonstrated that miR-145 is expressed in primordial follicles and modulates the initiation of primordial follicle development. We aimed to explore the function of miR-145 in mouse granulosa cells (mGCs).

MATERIALS AND METHODS

The proliferation and differentiation of GCs were examined via MTT, EDU assay, QRT-PCR, ELISA and electron microscope analysis. The target of miR-145 was determined by bioinformatics analysis and luciferase reporter assay and the molecular mechanisms were examined via western blot and quantitative Real-Time RT-PCR.

KEY FINDINGS

We proved that down-regulation of miR-145 could inhibit GCs proliferation and differentiation. In addition, we provided evidence that Crkl was the target gene of miR-145. The miR-145 antagomir caused an increase in Crkl expression and activation of the JNK/p38 MAPK pathway. Overexpression of Crkl with pEGFP-N1-Crkl vector inhibited GCs differentiation and progesterone synthesis as well as activation of the JNK/p38 MAPK pathway.

SIGNIFICANCE

Our study shows that miR-145 targets Crkl and through the JNK/p38 MAPK signaling pathway promotes the GCs proliferation, differentiation, and steroidogenesis. MiR-145 may play an important role in the ovarian physiology and pathology.

CircRNA SEPT9 contributes to malignant behaviors of glioma cells via miR-432-5p-mediated regulation of LASP1

BACKGROUND

Circular RNA (circRNA) septin 9 (circSEPT9; hsa_circ_0005320) has been reported to be abnormally up-regulated in glioma. However, the exact role and working mechanism of circSEPT9 in glioma progression are barely known.

METHODS

RNA and protein levels were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot assay, respectively. Cell proliferation was assessed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation assay and flow cytometry. Cell apoptosis was evaluated by flow cytometry. Cell motility was analyzed by transwell assays. Cell glycolytic metabolism was analyzed using commercial kits. Dual-luciferase reporter assay, RNA-pull down assay and RNA immunoprecipitation (RIP) assay were conducted to verify the intermolecular interactions. Xenograft mice model was utilized to assess the role of circSEPT9 in vivo.

RESULTS

CircSEPT9 was highly expressed in glioma tissues and cell lines. CircSEPT9 interference inhibited the proliferation, migration, invasion and glycolytic metabolism and triggered the apoptosis of glioma cells. MicroRNA-432-5p (miR-432-5p) was a target of circSEPT9, and circSEPT9 silencing-mediated effects in glioma cells were largely alleviated by the addition of anti-miR-432-5p. MiR-432-5p bound to the 3' untranslated region (3'UTR) of LIM and SH3 protein 1 (LASP1), and LASP1 overexpression largely overturned miR-432-5p-induced effects in glioma cells. CircSEPT9 up-regulated LASP1 expression by acting as miR-432-5p sponge. CircSEPT9 silencing suppressed xenograft tumor growth in vivo.

CONCLUSION

CircSEPT9 exerted an oncogenic role to enhance the malignant behaviors of glioma cells by binding to miR-432-5p to induce LASP1 expression.

Expression of mammalian sterile 20-like kinase 1 and 2 and Yes-associated protein 1 proteins in triple-negative breast cancer and the clinicopathological significance

BACKGROUND AND AIM

Mammalian sterile 20-like kinase 1 and 2 (MST1/2) and Yes-associated protein 1 (YAP1) are the core molecules of the Hippo signaling pathway, which have been found to be unbalanced in the occurrence of tumors and promote the development of the lesions. The present study aimed to investigate the expression of MST1/2 and YAP1 proteins in triple-negative breast cancer (TNBC) and their clinicopathological significance.

METHODS

Immunohistochemistry was used to detect the expression level of protein in tissues. According to the percentage of positive cells and staining intensity, the expression intensity of MST1/2 and YAP1 proteins in the tissue samples was scored, and the correlation between MST1/2 and the clinicopathological features of TNBC were discussed.

RESULTS

The expression of MST1/2 and YAP1 was associated with histological grade, metastasis, lymph node metastasis stage, and tumor node metastasis stage. The overexpression of YAP1 predicted a poor prognosis in terms of overall survival and disease-free survival time. The MST1/2 expression was associated with improved overall survival and disease free survival of the patients.

CONCLUSION

MST1/2 and YAP1 may be used as prognostic indicators to evaluate the recurrence of TNBC and might become one of the new targets for breast cancer treatment.

Increased PA2G4 Expression Is an Unfavorable Factor in Nasopharyngeal Carcinoma

PA2G4 plays a dual role in tumors. However, the correlation of its expression with clinical feature and prognosis has never been reported in nasopharyngeal carcinoma (NPC). Using immunohistochemical staining, we examined PA2G4 protein level in clinicopathologically characterized 201 NPC cases (138 male and 63 female) with age ranging from 21 to 83 years and 45 nasopharyngeal (NP) tissues. Statistical methods were used to assess the difference in PA2G4 expression and its relationship with clinical parameters and prognosis in NPC. Immunohistochemical analysis showed that the protein expression of PA2G4 examined in NPC tissues was higher than that in the nasopharyngeal tissues (P=0.005). In addition, high levels of PA2G4 protein were positively correlated with tumor size (T classification) (P<0.001), the status of lymph node metastasis (N classification) (P<0.001), distant metastasis (P=0.029), and clinical stage (P<0.001) of NPC patients. Patients with higher PA2G4 expression had a significantly shorter overall survival time than did patients with low PA2G4 expression. Stratified analysis indicated that high expression of PA2G4 showed the inversed survival time in clinical stages III-IV, but not stages I-II. Finally, multivariate analysis suggested that the level of PA2G4 expression was an independent prognostic indicator (P<0.001) for the survival of patients with NPC. Elevated protein expression of PA2G4 was significantly shown, which plays an unfavorable outcome for NPC patient survival.

Clinical significance of YAP1 and TAZ in esophageal squamous cell carcinoma

BACKGROUND

Esophageal cancer is the eighth most frequent and sixth most fatal cancer worldwide. This study aimed to investigate the clinical characteristics and prognostic significance of yes related protein 1 (YAP1) and transcriptional co-activator with PDZ binding motif (TAZ) in patients with esophageal squamous cell carcinoma (ESCC).

METHODS

A total of 306 ESCC pathological specimens and adjacent tissues (as control; tissues from the esophageal mucosa >5 cm from the edge of the tumor) were collected between January, 2008 and December, 2018. Immunohistochemical staining was used to assess the expression of YAP1 and TAZ proteins in the ESCC and adjacent tissues, and their relationship with clinicopathological parameters was evaluated using SPSS 21.0 software.

RESULTS

YAP1 and TAZ proteins were highly expressed in ESCC, and their expression was closely related to TNM stage and lymph node metastasis. Expression of YAP1 was associated with tumor size (P = .029), differentiation (P = .000), depth of invasion (P = .001), and TNM stage (P = .000). Expression of TAZ was associated with tumor size (P = .034), differentiation (P = .000), depth of invasion (P = .029), lymph node metastasis (P = .006), and ethnicity (P < .001). The expression of YAP1 protein was positively correlated with the expression of TAZ protein (r = 0.257, P < .05). YAP1 and TAZ expression (P = .039 and .000, respectively), tumor size (P = .041), and lymph node metastasis (P = .001) significantly affected the overall survival of patients with ESCC, and represent independent factors for overall survival.

CONCLUSION

YAP1 and TAZ proteins are highly expressed in ESCC, and closely related to the clinical and pathological parameters such as the diameter of the tumor, degree of differentiation, and depth of invasion, indicating that YAP1 and TAZ may be involved in the development of ESCC. YAP1 and TAZ may be used as prognostic markers in ESCC.

Expression of Delta Like Ligand 4 (DLL4) in endometrial carcinomas and tumor vasculature

PURPOSE

Delta like ligand 4 (DLL4) is a transmembrane ligand of the Notch Signalling pathway, that regulates blood vessel sprouting and maturation. We investigated the expression of DLL4 in endometrial cancer.

METHODS

DLL4 was assessed in the plasma (with ELISA) and tissues (with immunohistochemistry) 33 patients with endometrial cancer, treated with radical hysterectomy for stage I endometroid carcinoma. The angiogenic activity (AA) of endometrial cancer was quantified by assessing the CD31+ microvessel density (MVD) in the invading tumor front. Vascular maturation index (VMI), defined as the percentage of CD31+ microvessels expressing DLL4, was calculated as the ratio of the CD31+ MVD to the DLL4+ MVD.

RESULTS

The angiogenic activity was directly related with the histological grade (p=0.01). The VMI ranged from 0.1 to 0.7 (median 0.34). The concentration of DLL4 in the plasma ranged from 55-81pg/ml (mean 62.8) before, and dropped to 55-62 (mean 58.2) after hysterectomy (p<0.05). DLL4 was also expressed by cancer cells in 17/33 cases. No correlation between DLL4-related parameters with histopathological variables was noted.

CONCLUSION

This pilot study shows that DLL4 is overexpressed in endometrial cancer cells, vasculature and is also elevated in the plasma of a fraction of patients before surgery. The percentage of DLL4+ vessels in the penetrating sample ranged from 10-70%, indicating a large difference in the quality of angiogenesis produced between the endometrial tumors of the same histological type and differentiation.

Lnc-OIP5-AS1 exacerbates aorta wall injury during the development of aortic dissection through upregulating TUB via sponging miR-143-3p

AIMS

Dysfunction of major cells constituting the aortic wall is the pathological basis for AD development. Determining whether non-coding RNAs can influence AD progression by regulating these cellular functions and identifying some specific non-coding RNAs is of great significance in uncovering molecular mechanisms of the development of AD.

MAIN METHODS

Microarray analyses and hierarchical clustering analysis were used to select candidate lncRNAs and miRNAs associated with AD. Dual-luciferase reporter assay, RNA immunoprecipitation, and RNA pull-down assay were performed to verify the direct bonding relationship between genes. The regulatory effects of genes on cell function were examined in a series of experiments.

KEY FINDINGS

We found that lnc-OIP5-AS1 was upregulated, whereas miR-143-3p was downregulated in cells treated with angiotensin II (AngII) and AD tissues. Lnc-OIP5-AS1 functioned as a competing endogenous RNA (ceRNA) of miR-143-3p to suppress the proliferation and mobility, but promote apoptosis of HAECs and HASMCs, and simultaneously result in the imbalances between MMP-2/9 and TIMP-2/1 in HASMCs and the excessive secretion of IL-6, IL-1β, and IL-17A of HAAFs. Moreover, overexpression or silence of TUB, a target gene of miR-143-3p, counteracted the influence of miR-143-3p or lnc-OIP5-AS1 on cells, respectively.

SIGNIFICANCE

Our findings revealed that lncRNA OIP5-AS1 exacerbates aorta intima, media, and adventitia injury in the development of AD through upregulating TUB via sponging miR-143-3p and also support more detailed future studies by providing a novel molecular basis underlying AD formation.

Characterization hiPSC-derived neural progenitor cells and neurons to investigate the role of NOS1AP isoforms in human neuron dendritogenesis

Abnormal dendritic arbor development has been implicated in a number of neurodevelopmental disorders, such as autism and Rett syndrome, and the neuropsychiatric disorder schizophrenia. Postmortem brain samples from subjects with schizophrenia show elevated levels of NOS1AP in the dorsolateral prefrontal cortex, a region of the brain associated with cognitive function. We previously reported that the long isoform of NOS1AP (NOS1AP-L), but not the short isoform (NOS1AP-S), negatively regulates dendrite branching in rat hippocampal neurons. To investigate the role that NOS1AP isoforms play in human dendritic arbor development, we adapted methods to generate human neural progenitor cells and neurons using induced pluripotent stem cell (iPSC) technology. We found that increased protein levels of either NOS1AP-L or NOS1AP-S decrease dendrite branching in human neurons at the developmental time point when primary and secondary branching actively occurs. Next, we tested whether pharmacological agents can decrease the expression of NOS1AP isoforms. Treatment of human iPSC-derived neurons with d-serine, but not clozapine, haloperidol, fluphenazine, or GLYX-13, results in a reduction in endogenous NOS1AP-L, but not NOS1AP-S, protein expression; however, d-serine treatment does not reverse decreases in dendrite number mediated by overexpression of NOS1AP isoforms. In summary, we demonstrate how an in vitro model of human neuronal development can help in understanding the etiology of schizophrenia and can also be used as a platform to screen drugs for patients.

LncRNA RHPN1-AS1 accelerates proliferation, migration, and invasion via regulating miR-485-5p/BSG axis in hepatocellular carcinoma

It is reported that long noncoding RNA RHPN1-AS1 (lncRNA RHPN1-AS1) functions as an oncogene among multiple types of cancers; however, the effect of lncRNA RHPN1-AS1 in hepatocellular carcinoma (HCC) is left to be investigated. The main purpose of this work was to study the effects of lncRNA RHPN1-AS1/miR-485-5p system on proliferation, migration, and invasion in HCC and future investigate the latent mechanisms. Our work found that lncRNA RHPN1-AS1 was observably up-regulated in HCC tissues and cell lines, especially HCCLM3 and SMMC-7721 cells. LncRNA RHPN1-AS1 knockdown decreased the capacity of proliferation, invasion, and migration in HCCLM3 and SMMC-7721 cells, which could be crippled by miR-485-5p inhibitor. Besides, the expression of basigin (BSG) was decreased after lncRNA RHPN1-AS1 silence, indicating the function of lncRNA RHPN1-AS1/miR-485-5p/BSG axis in HCC progression. Our study opens novel insights to help understand the mechanisms of lncRNA RHPN1-AS1/miR-485-5p/BSG axis in HCC progression, which may provide a new therapeutic target for HCC treatment.

Upregulation of MTOR, RPS6KB1, and EIF4EBP1 in the whole blood samples of Iranian patients with multiple sclerosis compared to healthy controls

Various genetic and epigenetic mechanisms have been suggested to play roles as the underlying pathophysiology of Multiple Sclerosis (MS). Changes in different parts of the mTOR signaling pathway are among the potential suggested mechanisms based on the specific roles of this pathway in CNS. MTOR, RPS6KB1, and EIFEBP1 genes are among important genes in the mTOR pathway, responsible for the proper function of acting proteins in this signaling pathway. This study aimed to investigate the relative expression levels of these genes in the blood samples of relapsing-remitting MS (RRMS) patients compared to healthy controls. In this case-control study blood samples were collected from 30 newly diagnosed RRMS patients and 30 age and sex-matched healthy controls. mRNA level of MTOR, RPS6KB1, and EIFEBP1 genes were assessed using Real-Time PCR. The expression of MTOR, RPS6KB1, and EIF4EBP1 genes was up regulated in MS patients compared to healthy controls (p < 0.001 for all mentioned genes). Considering gender differences, expression of the mentioned genes was increased among female patients (all P < 0.001). However, no statistically significant changes were observed among male patients. Based on the receiver operating characteristic, MTOR gene had the highest diagnostic value followed by EIF4EBP1 and RPS6KB1 genes in differentiating RRMS patients from controls. In conclusion, we found the simultaneous upregulation of MTOR, RPS6KB1, and EIF4EBP1 genes among RRMS patients. MTOR showed to have the highest diagnostic value compared to other 2 genes in differentiating RRMS patients. Further studies evaluating the importance of these findings from pharmacological and prognostic perspectives are necessary.

Pseudogene PA2G4P4 promotes oncogene PA2G4 expression and nuclear translocation to affect glioblastoma cell viability and apoptosis

Dysregulation of pseudogenes is involved in the progression of various types of cancer, including glioblastoma (GBM). Proliferation associated-2G4 (PA2G4) pseudogene 4 (PA2G4P4) has been shown to play an oncogenic role in bladder cancer development. Our study aimed to explore the role and mechanism of PA2G4P4 in GBM progression. PA2G4P4 and PA2G4 expression in GBM tissues was analyzed using the GEPIA database. Cell viability, apoptosis, and activities of caspase-3 and caspase-9 in GBM cells were explored by CCK-8, flow cytometry analysis, and colorimetric activity assay kits, respectively. GEPIA database showed that PA2G4P4 and PA2G4 were both upregulated in GBM tissues. PA2G4P4 expression was also boosted in GBM cells. Knockdown of PA2G4P4 or PA2G4 inhibited cell viability, induced apoptosis, and increased caspase-3 and caspase-9 activities in GBM cells. Data from UALCAN database showed that among top 15 genes correlated with PA2G4P4, PA2G4 had the highest correlation coefficient. Additionally, knockdown of PA2G4P4 inhibited PA2G4 expression and nuclear translocation in GBM cells. Overexpression of PA2G4 abolished the functions of PA2G4P4 knockdown on viability and apoptosis in GBM cells. Summarily, pseudogene PA2G4P4 promotes oncogene PA2G4 expression and nuclear translocation to affect cell viability and apoptosis in GBM cells.

Inflammation-induced PINCH expression leads to actin depolymerization and mitochondrial mislocalization in neurons

BACKGROUND

Diseases and disorders with a chronic neuroinflammatory component are often linked with changes in brain metabolism. Among neurodegenerative disorders, people living with human immunodeficiency virus (HIV) and Alzheimer's disease (AD) are particularly vulnerable to metabolic disturbances, but the mechanistic connections of inflammation, neurodegeneration and bioenergetic deficits in the central nervous system (CNS) are poorly defined. The particularly interesting new cysteine histidine-rich-protein (PINCH) is nearly undetectable in healthy mature neurons, but is robustly expressed in tauopathy-associated neurodegenerative diseases including HIV infection and AD. Although robust PINCH expression has been reported in neurons in the brains of patients with HIV and AD, the molecular mechanisms and cellular consequences of increased PINCH expression in CNS disease remain largely unknown.

METHODS

We investigated the regulatory mechanisms responsible for PINCH protein-mediated changes in bioenergetics, mitochondrial subcellular localization and bioenergetic deficits in neurons exposed to physiological levels of TNFα or the HIV protein Tat. Changes in the PINCH-ILK-Parvin (PIP) complex association with cofilin and TESK1 were assessed to identify factors responsible for actin depolymerization and mitochondrial mislocalization. Lentiviral and pharmacological inhibition experiments were conducted to confirm PINCH specificity and to reinstate proper protein-protein complex communication.

RESULTS

We identified MEF2A as the PINCH transcription factor in neuroinflammation and determined the biological consequences of increased PINCH in neurons. TNFα-mediated activation of MEF2A via increased cellular calcium induced PINCH, leading to disruption of the PIP ternary complex, cofilin activation by TESK1 inactivation, and actin depolymerization. The disruption of actin led to perinuclear mislocalization of mitochondria by destabilizing the kinesin-dependent mitochondrial transport machinery, resulting in impaired neuronal metabolism. Blocking TNFα-induced PINCH expression preserved mitochondrial localization and maintained metabolic functioning.

CONCLUSIONS

This study reported for the first time the mechanistic and biological consequences of PINCH expression in CNS neurons in diseases with a chronic neuroinflammation component. Our findings point to the maintenance of PINCH at normal physiological levels as a potential new therapeutic target for neurodegenerative diseases with impaired metabolisms.

A-kinase interacting protein 1 high expression correlates with advanced tumor stage and poor overall survival in surgical patients with clear cell renal cell carcinoma

The present study aimed to detect the A-kinase interacting protein 1 (AKIP1) expression in clear cell renal cell carcinoma (ccRCC) tumor tissues and adjacent tissues, and further investigate the correlation of tumor AKIP1 expression with clinicopathological features and survival profile in ccRCC patients.Totally 210 ccRCC patients who underwent resection were retrospectively reviewed, and their tumor and adjacent tissue specimens were acquired for immunohistochemical detection of AKIP1 expression. The survival data of patients were collected for overall survival (OS) assessment.AKIP1 was upregulated in ccRCC tumor tissues compared with adjacent tissues (P < .001). Tumor AKIP1 expression was positively associated with T stage (P = .019), N stage (P = .032), and TNM stage (P = .005) in ccRCC patients. According to AKIP1 expression in tumor tissues, all patients were grouped as AKIP1 low and high expression (AKIP1 high expression were further divided into AKIP1 high+, high++, and high+++ expression). OS was the lowest in the patients with AKIP1 high+++ expression, followed by those with AKIP1 high++ expression and AKIP1 high+ expression, and then patients with AKIP1 low expression (P < .001). Furthermore, multivariate Cox regression exhibited tumor AKIP1 high expression (P = .017), age (>60 years) (P = .030), pathological grade (G2/G3 vs G1) (P = .037), and TNM stage (II/III vs I) (P < .001) were independent predictive factors for decreased OS in ccRCC patients.AKIP1 presents potency to be a novel biomarker for tumor progression and prognosis surveillance in ccRCC.

A novel ETV6-miR-429-CRKL regulatory circuitry contributes to aggressiveness of hepatocellular carcinoma

BACKGROUND

Tumor metastasis is one of the main causes of the high mortality of hepatocellular carcinoma (HCC). E-Twenty Six variant gene 6 (ETV6) is a strong transcriptional repressor, associated with the development and progression of tumors. However, the exact role and underlying mechanism of ETV6 in HCC remain unclear.

METHODS

Western blotting, quantitative real-time PCR and immunohistochemistry were used to detect the expression levels of ETV6, CRKL (v-crk sarcoma virus CT10 oncogene homologue (avian)-like) and miR-429 in HCC tissues and cells; Transwell chamber and F-actin cytoskeleton staining assay to examine the effects of ETV6 and CRKL deregulation on the migration, invasion and cytoskeleton of HCC cells; Co-immunoprecipitation assay to determine the interaction between CRKL and ETV6; Chromatin immunoprecipitation assay to investigate the interaction between ETV6 and miR-429.

RESULTS

We established a novel ETV6-miR-429-CRKL regulatory circuitry contributes to HCC metastasis. ETV6 and CRKL were frequently increased, while miR-429 was downregulated in both hepatocarcinoma tissues and hepatocarcinoma cells. Moreover, ETV6 upregulation was positively correlated with CRKL upregulation, and two negative correlations were also established for ETV6 and CRKL upregulation with miR-429 downregulation in both hepatocarcinoma patients' tumorous tissues and hepatocarcinoma cells. Functional investigations revealed that overexpression and knockdown of ETV6 was remarkably effective in promoting and suppressing HCC cell migration, invasion, cytoskeleton F-actin expression and arrangement, whereas, CRKL overexpression exhibited similar effects to the overexpression of ETV6. Mechanistically, ETV6 negatively regulates miR-429 expression by directly binding to the promoter region of miR-429; miR-429 negatively regulates CRKL expression by selectively targeting CRKL-3'-UTR; ETV6 directly binds to CRKL and positively regulates its expression, which in turn CRKL positively regulates ETV6 expression.

CONCLUSIONS

Our data demonstrated that ETV6 promotes migration and invasion of HCC cells by directly binding to promoter region of miR-429 via modulating CRKL expression. The newly identified ETV6-miR-429-CRKL regulatory circuitry contributes to the aggressiveness of HCC, which provides new clues for fundamental research on diagnosis and treatment parameters for HCC.

ASPP1 deficiency promotes epithelial-mesenchymal transition, invasion and metastasis in colorectal cancer

The apoptosis-stimulating protein of p53 (ASPP) family of proteins can regulate apoptosis by interacting with the p53 family and have been identified to play an important role in cancer progression. Previously, we have demonstrated that ASPP2 downregulation can promote invasion and migration by controlling β-catenin-dependent regulation of ZEB1, however, the role of ASPP1 in colorectal cancer (CRC) remains unclear. We analyzed data from The Cancer Genome Atlas (TCGA) and coupled this to in vitro experiments in CRC cell lines as well as to experimental pulmonary metastasis in vivo. Tissue microarrays of CRC patients with information of clinical-pathological parameters were also used to investigate the expression and function of ASPP1 in CRC. Here, we report that loss of ASPP1 is capable of enhancing migration and invasion in CRC, both in vivo and in vitro. We demonstrate that depletion of ASPP1 could activate expression of Snail2 via the NF-κB pathway and in turn, induce EMT; and this process is further exacerbated in RAS-mutated CRC. ASPP1 could be a prognostic factor in CRC, and the use of NF-κB inhibitors may provide new strategies for therapy against metastasis in ASPP1-depleted CRC patients.

MicroRNA-16 inhibits the proliferation and metastasis of human lung cancer cells by modulating the expression of YAP1

PURPOSE

Accounting for significant human morbidity and mortality across the globe, lung cancer is the most prevalent type of cancer as far as incidence and mortality is concerned. MicroRNAs (miRs) have shown an amazing potential to act as therapeutic agents for the management of several human diseases. This study investigated the function of miR-16 in lung cancer.

METHODS

The normal lung cancer cell line MRC3 and lung cancer cell lines SK-MES-1, A549, MS-53 and SK-LU-1 were used in the present study. The qRT-PCR was used for expression profiling of miR-16 and yes associated protein 1 (YAP1). WST-1 assay was used to monitor the proliferation rate. Flow cytometry was used for cell cycle analysis. Apoptosis was examined by DAPI and annexin V/propidium iodide (PI) staining. TargetScan analysis was performed to identify the potential target of miR-16 and western blot analysis was done to estimate the protein expression.

RESULTS

The gene expression analysis showed miR-16 to be suppressed in lung cancer tissues and cell lines. Overexpression of miR-16 inhibited the growth and metastasis of the DMS-53 lung cancer cells via induction of the apoptotic cell death. Bioinformatic approaches revealed miR-16 exerts its effects by targeting YAP1. YAPI expression was found elevated in lung cancer tissues and its silencing halted the growth of the DMS-53 lung cancer cells. Nonetheless, YAP1 overexpression could reverse the growth inhibitory effects of miR-16.

CONCLUSION

Taken together, miR-16 may serve as novel therapeutic target for the treatment of lung cancer.

Different Effects of Fluoride Exposure on the Three Major Bone Cell Types

Fluoride accumulates and is toxic to bones. Clinical bone lesions occur in a phased manner, being less severe early in the natural course of skeletal fluorosis. Previous research rarely focused on osteocyte, osteoclast, and osteoblast at the same time, although these three types of cells are involved in the process of fluorosis. In this study, commitment of bone cells was performed according to their respective characteristics. Osteocyte-like cells were verified by protein expression of sclerostin (SOST) in IDG-SW3 cell culture with mineral medium. Positive tartrate-resistant acid phosphatase (TRACP) staining, characteristic of osteoclasts, is observed in RAW264.7 cells after administration of RANKL. We successfully purified a high percentage (94%) of bone mesenchymal stem cells (BMSCs) co-expressing CD34 and CD44. Parallel studies were performed to observe cell viability and apoptosis rates in osteocyte, osteoclast, and osteoblast like cells by using MTT and Annexin V FITC assays. Our results demonstrated that osteocytes have a strong tolerance to high fluoride concentrations, while osteoclasts are more sensitive to changes of fluoride dose. The range of anabolic action of fluoride concentration on osteoblast was narrow. Notably, fluoride exposure aggravated apoptosis of osteocyte and osteoclast induced by administration of PTH and TGF-β, respectively. In short, three types of bone cells display disparate responses to fluoride exposure and to PTH- and TGF-β-induced apoptosis.

Par6 regulates cell cycle progression through enhancement of Akt/PI3K/GSK-3β signaling pathway activation in glioma

As the key factor of the polarity protein complex, Par6 not only regulates polarization processes, but also plays important roles in tumor metastasis and progression in many epithelium malignancy tumors. Here, we showed that Par6 is an essential component in glioma tumorigenesis. Our results indicated the aberrant expression of Par6 in malignant glioma tissues and cell lines. We found that the regulation of Par6 expression induces cell proliferation and tumor growth in vivo and in vitro. Additionally, RNA-seq revealed the effects of Par6 were associated with cyclin D1-regulated cell cycle progression in glioma cells. Moreover, our results demonstrated that the regulation of Par6 can enhance the activation of Akt/PI3K signaling pathway, and subsequently upregulate the expression level of GSK-3β protein, which then regulate cyclin D1-mediated cell cycle regulation. Furthermore, we found that TGF-β-induced the upregulation of Par6 expression may be involved in this process. The pathological analysis confirmed the correlation between Par6 expression and the prognosis in human glioma tissues, suggesting the regulation of Par6 expression regulates glioma tumorigenesis and progression. Thus, our findings showed that Par6 might be a potential biomarker for the diagnosis and providing a therapeutic strategy for the treatment of malignant glioma.

Sostdc1 is expressed in all major compartments of developing and adult mammalian eyes

PURPOSE

This study was conducted in order to study Sostdc1 expression in rat and human developing and adult eyes.

METHODS

Using the yeast signal sequence trap screening method, we identified the Sostdc1 cDNA encoding a protein secreted by the adult rat retinal pigment epithelium. We determined by in situ hybridization, RT-PCR, immunohistochemistry, and western blot analysis Sostdc1 gene and protein expression in developing and postnatal rat ocular tissue sections. We also investigated Sostdc1 immunohistolocalization in developing and adult human ocular tissues.

RESULTS

We demonstrated a prominent Sostdc1 gene expression in the developing rat central nervous system (CNS) and eyes at early developmental stages from E10.5 days postconception (dpc) to E13 dpc. Specific Sostdc1 immunostaining was also detected in most adult cells of rat ocular tissue sections. We also identified the rat ocular embryonic compartments characterized by a specific Sostdc1 immunohistostaining and specific Pax6, Sox2, Otx2, and Vsx2 immunohistostaining from embryonic stages E10.5 to E13 dpc. Furthermore, we determined the localization of SOSTDC1 immunoreactivity in ocular tissue sections of developing and adult human eyes. Indeed, we detected SOSTDC1 immunostaining in developing and adult human retinal pigment epithelium (RPE) and neural retina (NR) as well as in several developing and adult human ocular compartments, including the walls of choroidal and scleral vessels. Of utmost importance, we observed a strong SOSTDC1 expression in a pathological ocular specimen of type 2 Peters' anomaly complicated by retinal neovascularization as well in the walls ofother pathological extra-ocular vessels.  CONCLUSION: As rat Sostdc1 and human SOSTDC1 are dual antagonists of the Wnt/β-catenin and BMP signaling pathways, these results underscore the potential crucial roles of these pathways and their antagonists, such as Sostdc1 and SOSTDC1, in developing and adult mammalian normal eyes as well as in syndromic and nonsyndromic congenital eye diseases.

The Inhibitory Effect of (-)-Epigallocatechin-3-Gallate on Breast Cancer Progression via Reducing SCUBE2 Methylation and DNMT Activity

Epigenetic modifications are important mechanisms responsible for cancer progression. Accumulating data suggest that (-)-epigallocatechin-3-gallate (EGCG), the most abundant catechin of green tea, may hamper carcinogenesis by targeting epigenetic alterations. We found that signal peptide-CUB (complement protein C1r/C1s, Uegf, and Bmp1)-EGF (epidermal growth factor) domain-containing protein 2 (SCUBE2), a tumor suppressor gene, was hypermethylated in breast tumors. However, it is unknown whether EGCG regulates SCUBE2 methylation, and the mechanisms remain undefined. This study was designed to investigate the effect of EGCG on SCUBE2 methylation in breast cancer cells. We reveal that EGCG possesses a significantly inhibitory effect on cell viability in a dose- and time-dependent manner and presents more effects than other catechins. EGCG treatment resulted in enhancement of the SCUBE2 gene, along with elevated E-cadherin and decreased vimentin expression, leading to significant suppression of cell migration and invasion. The inhibitory effect of EGCG on SCUBE2 knock-down cells was remarkably alleviated. Further study demonstrated that EGCG significantly decreased the SCUBE2 methylation status by reducing DNA methyltransferase (DNMT) expression and activity. In summary, this study reported for the first time that SCUBE2 methylation can be reversed by EGCG treatment, finally resulting in the inhibition of breast cancer progression. These results suggest the epigenetic role of EGCG and its potential implication in breast cancer therapy.

Effects of body temperature on the expression and localization of meiosis-related proteins STRA8 and SCP3 in boar testes

Body temperature could lead to interruption of spermatogenesis, but the molecular mechanism was still unclear. Cryptorchidism was defined as the failure of testes to enter the scrotum, which exposed the testes to body temperature. Meiosis was a unique feature of germ cell development. Whether cryptorchidism damage the initiation of meiosis in boars had not been reported. The aim of this study was to determine whether spermatogonia in the cryptorchid testes entered into meiosis by detecting meiosis-related markers stimulated by retinoic acid gene 8 (STRA8) and synaptonemal complex protein 3 (SCP3). Three boars with spontaneous unilateral abdominal cryptorchidism were used. The testis located in the abdomen was cryptorchidism group, the scrotal testis of the same animal was used as control. HE results showed that only Sertoli cells, and a few spermatogonia remained in the seminiferous tubules, and no spermatids were seen compared with the control. Immunohistochemistry results showed that in both control and cryptorchidism group, STRA8 was mainly expressed in the nucleus of spermatogonia and spermatocytes. In control group, SCP3 was expressed in the nucleus of spermatocytes. In cryptorchidism group, SCP3 immunopositive cells were also observed. qRT-PCR and Western Blot results showed that the mRNA and protein levels of STRA8 and SCP3 were significantly decreased in cryptorchid boars. The expression of STRA8 and SCP3 in cryptorchidism suggested that spermatogonia could still enter meiosis in cryptorchid boars.

Dihydrotestosterone inhibits arylsulfatase B and Dickkopf Wnt signaling pathway inhibitor (DKK)-3 leading to enhanced Wnt signaling in prostate epithelium in response to stromal Wnt3A

BACKGROUND

In tissue microarrays, immunostaining of the enzyme arylsulfatase B (ARSB; N-acetylgalactosamine-4-sulfatase) was less in recurrent prostate cancers and in cancers with higher Gleason scores. In cultured prostate stem cells, decline in ARSB increased Wnt signaling through effects on Dickkopf Wnt Signaling Pathway Inhibitor (DKK)3. The effects of androgen exposure on ARSB and the impact of decline in ARSB on Wnt signaling in prostate tissue were unknown.

METHODS

Epithelial and stromal tissues from malignant and normal human prostate were obtained by laser capture microdissection. mRNA expression of ARSB, galactose-6-sulfate-sulfatase (GALNS) and Wnt-signaling targets was determined by QPCR. Non-malignant human epithelial and stromal prostate cells were grown in tissue culture, including two-cell layer cultures. ARSB was silenced by specific siRNA, and epithelial cells were treated with stromal spent media following treatment with IWP-2, an inhibitor of Wnt secretion, and by exogenous recombinant human Wnt3A. Promoter methylation was detected using specific DKK3 and ARSB promoter primers. The effects of DHT and of ARSB overexpression on DKK expression were determined. Cell proliferation was assessed by BrdU incorporation.

RESULTS

Normal stroma showed higher expression of vimentin, ARSB, and Wnt3A than epithelium. Normal epithelium had higher expression of E-cadherin, galactose 6-sulfate-sulfatase (GALNS), and DKK3 than stroma. In malignant epithelium, expression of ARSB and DKK3 declined, and expression of GALNS and Wnt signaling targets increased. In cultured prostate epithelial cells, Wnt-mediated signaling was greatest when ARSB was silenced and cells were exposed to exogenous Wnt3A. Exposure to 5α-dihydrotestosterone (DHT) increased ARSB and DKK3 promoter rmethylation, and effects of DHT on DKK3 expression were reversed when ARSB was overexpressed.

CONCLUSIONS

Androgen-induced declines in ARSB and DKK3 may contribute to prostate carcinogenesis by sustained activation of Wnt signaling in prostate epithelium in response to stromal Wnt3A.

Liprin alfa 2 gene expression is increased by cannabis use and associated with neuropsychological function

The relation of heavy cannabis use with decreased neuropsychological function has frequently been described but the underlying biological mechanisms are still largely unknown. This study investigates the relation of cannabis use with genome wide gene expression and subsequently examines the relations with neuropsychological function. Genome-wide gene expression in whole blood was compared between heavy cannabis users (N = 90) and cannabis naïve participants (N = 100) that were matched for psychotic like experiences. The results were validated using quantitative real-time PCR. Psychotic like experiences were assessed using the Comprehensive Assessment of Psychotic Experiences (CAPE). Neuropsychological function was estimated using four subtasks of the Wechsler Adult Intelligence Scale (WAIS). Subsequent in vitro studies in monocytes and a neuroblastoma cell line investigated expression changes in response to two major psychotropic components of cannabis; tetrahydrocannabinol (THC) and cannabidiol (CBD). mRNA expression of Protein Tyrosine Phosphatase Receptor Type F Polypeptide-Interacting-Protein Alpha-2 (PPFIA2) was significantly higher in cannabis users (LogFold Change 0.17) and confirmed by qPCR analysis. PPFIA2 expression level was negatively correlated with estimated intelligence (B=-22.9, p = 0.002) also in the 100 non-users (B=-28.5, p = 0.037). In vitro exposure of monocytes to CBD led to significant increase in PPFIA2 expression. However, exposure of monocytes to THC and neuroblastoma cells to THC or CBD did not change PPFIA2 expression. Change in PPFIA2 gene expression in response to cannabinoids is a putative mechanism by which cannabis could influence neuropsychological functions. The findings warrant further exploration of the role of PPFIA2 in cannabis induced changes of neuropsychological function, particularly in relation to CBD.

Curcumin ameliorates PRMT5-MEP50 arginine methyltransferase expression by decreasing the Sp1 and NF-YA transcription factors in the A549 and MCF-7 cells

The protein arginine methyltransferase 5 (PRMT5) and its catalytic partner methylosome protein MEP50 (WDR77) catalyse the mono- and symmetric di-methylation of selective arginines in various histones and non-histone target proteins. It has emerged as a crucial epigenetic regulator in cell proliferation and differentiation; which also reported to be overexpressed in many forms of cancers in humans. In this study, we aimed to assess the modulations in the expression of this enzyme upon exposure to the well-studied natural compound from the spice turmeric, curcumin. We exposed the lung and breast cancer cell lines (A549 and MCF-7) to curcumin (2 and 20 μM) and observed a highly significant inhibitory effect on the expression of both PRMT5 and MEP50. The level of symmetrical dimethylarginine (SDMA) in multiple proteins, and more specifically, the H4R3me2s mark (which predominates in GC-rich motifs in nucleosomal DNA) was also diminished significantly. We also found that curcumin significantly reduced the level and enrichment of the transcription factors Sp1 and NF-YA which shares their binding sites within the GC-rich region of the PRMT5 proximal promoter. Furthermore, the involvement of both PKC-p38-ERK-cFos and AKT-mTOR signalling was observed in reducing the Sp1 and NF-YA expression by curcumin. Therefore, we propose curcumin decreased the expression of PRMT5 in these cells by affecting at least these two transcription factors. Altogether, we report a new molecular target of curcumin and further elucidation of this proposed mechanism through which curcumin affects the PRMT5-MEP50 methyltransferase expression might be explored for its therapeutic application.

High-fat and high-glucose microenvironment decreases Runx2 and TAZ expression and inhibits bone regeneration in the mouse

BACKGROUND

Type 2 diabetes mellitus (T2DM) and hyperlipidemia are negatively related to bone regeneration. The aim of this study was to evaluate the effect of high-fat and high-glucose microenvironment on bone regeneration and to detect the expression of runt-related transcription factor 2 (Runx2) and transcriptional co-activator with PDZ-binding domain (TAZ) during this process.

METHODS

After establishing a high-fat and high-glucose mouse model, a 1 mm × 1.5 mm bone defect was developed in the mandible. On days 7, 14, and 28 after operation, bone regeneration was evaluated by hematoxylin-eosin staining, Masson staining, TRAP staining, and immunohistochemistry, while Runx2 and TAZ expression were detected by immunohistochemistry, RT-PCR, and Western blot analysis.

RESULTS

Our results showed that the inhibition of bone regeneration in high-fat and high-glucose group was the highest among the four groups. In addition, the expression of Runx2 in high-fat, high-glucose, and high-fat and high-glucose groups was weaker than that in the control group, but the expression of TAZ only showed a decreasing trend in the high-fat and high-glucose group during bone regeneration.

CONCLUSIONS

In conclusion, these results suggest that high-fat and high-glucose microenvironment inhibits bone regeneration, which may be related to the inhibition of Runx2 and TAZ expression.

HBXIP protein overexpression predicts the poor prognosis of pancreatic ductal adenocarcinomas

BACKGROUND

Hepatitis B virus X-interacting protein (HBXIP) is associated with a variety of tumors. The purpose of this study was to investigate the clinicopathological significance of HBXIP expression in pancreatic ductal adenocarcinoma (PDAC) and to explore its potential as a biomarker for PDAC.

METHODS

Immunohistochemical (IHC) staining was performed on 126 PDAC tissues, 36 paraneoplastic tissues and 22 normal pancreatic tissues. The relationship between high levels of HBXIP expression and pathological features of PDAC patients was evaluated by chi-squared values.

RESULTS

The positive rate of HBXIP protein in PDAC tissues was 85.7% (108/126), which was significantly higher than that of adjacent pancreatic tissue (41.7%, 15/36) and normal pancreas (18.2%, 4/22). In addition, strong positive expression of HBXIP was associated with tumor size, positive lymph node metastasis, clinical stage and 80-month overall survival. Patient's age, gender, degree of differentiation, Ki-67 expression index, and calcification were, however, not associated with high levels of HBXIP expression.

CONCLUSIONS

We present association between HBXIP expression and the pathological features of patients with PDAC.

Specific Soft-Tissue Invasion and LMP1 Expression Are Potential Indicators of Extranodal NK/T Cell Lymphoma, Nasal Type

BACKGROUND Extranodal NK/T cell lymphoma, nasal type (ENKTL-NT) is difficult to distinguish from nasal polyps and inverted papilloma, leading to its high misdiagnosis ratio. The aim of this study was to investigate its potential prognostic indicators. MATERIAL AND METHODS Kaplan-Meier method was used to calculate overall survival (OS) rate. Cox proportional hazards regression was used to analyze risk ratios (ORs) with 95% confidence intervals (CIs). RESULTS Nasal ala infiltration and nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm were potential prognostic factors for OS (p=0.0323 and 0.0072, respectively). Cox proportional-hazards regression indicated that high LMP1 expression and the nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm were the independent risk factors for poor OS of ENKTL-NT (HR=3.0655, p=0.028; HR=2.3650, p=0.0452, respectively). In the subgroup analysis, the OS rate was lower when the nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm in the patients who had high expression of LMP1 (p=0.0651), whereas high LMP1 expression increased the risk of worse prognostic outcome in patients with deep infiltration thickness. Thus, high LMP1 expression may contribute to the tissue invasion of ENKTL-NT. CONCLUSIONS Any patient with nasal ala soft-tissue invasion, nasal floor thickness >2.0 mm/nasal septum thickness >2.5 mm on CT imaging or high LMP1 expression should prompt immediate histopathologic diagnosis to rule out ENKTL-NT in clinical practice.

Perturbation of epithelial apicobasal polarity by rhomboid family-1 gene overexpression

The human rhomboid family (RHBDF)1 gene is highly expressed in breast cancer under clinical conditions but not in normal mammary gland tissues. Silencing the RHBDF1 gene in breast cancer xenograft tumors leads to inhibition of tumor growth. We show in this study that artificially raising RHBDF1 protein levels in the mammary epithelial cells MCF-10A results in severe perturbations of the ability of the cells to form lumen-containing acini, either in 3-dimensional cell cultures or implanted in mouse mammary fat pads. Knocking down RHBDF1 with short hairpin (sh)RNA leads to restoration of acinus formation. Consistently, RHBDF1 overexpression gives rise to disordered distribution of polarity markers GM130 and laminin-5, which otherwise are located in apical and basal positions, respectively, in the acini. Further investigations reveal that RHBDF1 directly binds to Par6a, a component of a protein complex consisting of partitioning-defective scaffold protein (Par)6, Par3, renin-angiotensin system-related C3 botulinum toxin substrate (Rac)1, and cell-division cycle (Cdc)42, which is structurally critical to the formation of apicobasal polarity. RHBDF1 binding to Par6a results in collapse of the protein complex and thus disruption of polarity formation. Since early stages of breast cancer are characterized by the loss of mammary gland epithelial cell polarity, our findings indicate that perturbations of apicobasal polarity by high levels of RHBDF1 is a significant attribute in the development of breast neoplasia.-Peng, X.-M., Gao, S., Deng, H.-T., Cai, H.-X., Zhou, Z., Xiang, R., Zhang, Q.-Z., Li, L.-Y. Perturbation of epithelial apicobasal polarity by rhomboid family-1 gene overexpression.

Up-regulation of NSP3 by Oligomeric Aβ Accelerates Neuronal Death Through Cas-independent Rap1A Activation

β-Amyloid (Aβ) plays an important role in the early pathogenesis of Alzheimer's disease (AD). In vitro studies have demonstrated that Aβ oligomers induce hippocampal and neocortical neuronal death. However the neurotoxic mechanisms by which soluble Aβ oligomers cause neuronal damage and death remain to be fully elucidated. To this end, we analyzed the gene expression profile of rat cerebral cortical neurons treated with Aβ oligomers in vitro. Aβ treatment induced the expression of novel SH2-containing protein 3 (NSP3), an adaptor molecule interacting with Cas family proteins. NSP3 expression was upregulated not only in oligomeric-Aβ-treated cultured neurons but also in the neocortex of aged Tg2576 mice. NSP3 overexpression in cultured cortical neurons accelerated neuronal death. The C-terminal region of NSP3 unbound to a Cas protein was necessary for the NSP3-induced acceleration of neuronal death, as was Cas-independent Rap1A activation downstream of NSP3. Moreover, NSP3 RNAi knockdown partially rescued Aβ-oligomer-treated neurons. These results indicate that NSP3 upregulation by soluble Aβ oligomers may accelerate neuronal death via Cas-independent Rap1A activation, implicating NSP3 in the pathogenesis of AD.

Hippo component YAP promotes focal adhesion and tumour aggressiveness via transcriptionally activating THBS1/FAK signalling in breast cancer

BACKGROUND

Focal adhesion plays an essential role in tumour invasiveness and metastasis. Hippo component YAP has been widely reported to be involved in many aspects of tumour biology. However, its role in focal adhesion regulation in breast cancer remains unexplored.

METHODS

Tissue microarray was used to evaluate YAP expression in clinical breast cancer specimens by immunohistochemical staining. Cell migration and invasion abilities were measured by Transwell assay. A cell adhesion assay was used to measure the ability of cell adhesion to gelatin. The focal adhesion was visualized through immunofluorescence. Phosphorylated FAK and other proteins were detected by Western blot analysis. Gene expression profiling was used to screen differently expressed genes, and gene ontology enrichment was performed using DAVID software. The gene mRNA levels were measured by quantitative real-time PCR. The activity of the THBS1-promoter was evaluated by dual luciferase assay. Chromatin immunoprecipitation (ChIP) was used to verify whether YAP could bind to the THBS1-promoter region. The prediction of potential protein-interaction was performed with the String program. The ChIP sequence data of TEAD was obtained from the ENCODE database and analysed via the ChIP-seek tool. The gene expression dataset (GSE30480) of purified tumour cells from primary breast tumour tissues and metastatic lymph nodes was used in the gene set enrichment analysis. Prognostic analysis of the TCGA dataset was performed by the SurvExpress program. Gene expression correlation of the TCGA dataset was analysed via R2: Genomics Analysis and Visualization Platform.

RESULTS

Our study provides evidence that YAP acts as a promoter of focal adhesion and tumour invasiveness via regulating FAK phosphorylation in breast cancer. Further experiments reveal that YAP could induce FAK phosphorylation through a TEAD-dependent manner. Using gene expression profiling and bioinformatics analysis, we identify the FAK upstream gene, thrombospondin 1, as a direct transcriptional target of YAP-TEAD. Silencing THBS1 could reverse the YAP-induced FAK activation and focal adhesion.

CONCLUSION

Our results unveil a new signal axis, YAP/THBS1/FAK, in the modulation of cell adhesion and invasiveness, and provides new insights into the crosstalk between Hippo signalling and focal adhesion.

TIFA Promotes Cell Survival and Migration in Lung Adenocarcinoma

BACKGROUND/AIMS

TNF-α receptor-associated factor (TRAF)-interacting protein with a forkhead-associated (FHA) domain (TIFA) may mediate the impact of TRAF on the development of lung cancer. The current study was conducted to investigate the expression of TIFA in lung adenocarcinoma and its potential role in the regulation of cancer cell proliferation and migration, and its influence on patient survival.

METHODS

Specimens of lung adenocarcinoma tissues and their adjacent normal lung tissues were obtained from 116 patients who underwent surgical resection of lung cancer. The expression of TIFA in the lung tissues was examined by immunohistochemistry, immunoblotting, and real-time RT-PCR in four different lung cancer cell lines and one normal bronchial epithelial cell line (BEAS-2B). TIFA was silenced by RNAi technique, and cell proliferation was then assessed by the CCK8 method. Furthermore, cell migration was determined by wound-healing trans-well and wound-healing migration assays. Additionally, cell-cycle arrest and apoptosis were assessed by flow cytometry analysis.

RESULTS

TIFA was positively detected in 63 (54.3%) out of 116 lung adenocarcinoma specimens, which was significantly higher than the respective rate established in normal tissues adjacent to the tumor (30.1%, p < 0.05). The overall survival rate was significantly lower in the patients with positive TIFA expression than that in the patients with negative TIFA expression (p < 0.05). TIFA was also highly expressed in the lung cancer cell lines (H1299, H1975, and HCC827) tested. It is noteworthy that siRNA suppressed the expression of TIFA, which contributed to the attenuation of cell proliferation and migration, but promoted cell-cycle arrest and apoptosis. Furthermore, the silencing of TIFA caused upregulation of p53, p21, and cleaved-caspase-3, but downregulation of Bcl-2, cyclin D1, and CDK4, as well as phosphorylation of IKKß, IκB, and p65.

CONCLUSIONS

TIFA may serve as a biomarker in the prediction of lung adenocarcinoma. Furthermore, TIFA may modulate lung cancer cell survival and proliferation through regulating the synthesis of apoptosis-associated proteins.

COPB2 promotes cell proliferation and tumorigenesis through up-regulating YAP1 expression in lung adenocarcinoma cells

Lung adenocarcinoma is the most common subtype of non-small cell lung cancer and responsible for more than 500,000 deaths per year worldwide. In this study, we aimed to explore the effects of COPB2 in the progression of lung adenocarcinoma and its underlying mechanism. The mRNA and protein levels of COPB2 in tumor tissues and cell lines were determined by qRT-PCR and western blotting analysis. siRNAs and over-expressed vector targeting COPB2 were used to down-regulate and up-regulate COPB2 expression in lung adenocarcinoma cell lines H1975. Cell apoptosis rate, proliferation and tumorigenesis of H1975 cells were determined by flow cytometry analysis, MTT assay and in vivo xenotransplantation assay, respectively. Western blotting and immunofluorescence assays were performed to evaluate the effects of COPB on the expression and subcellular location of YAP. Results showed COPB2 was significantly up-regulated in lung adenocarcinoma tissues and cell lines, which showed a close correlation with advanced clinical symptoms, such as tumor differentiation, TNM stage and the occurrence of lymph node metastasis and distance metastasis. Besides, the overall survival time of patients with high expression of COPB2 was shorter than that of patients with low COPB2 expression. After knockdown of COPB2, cell apoptosis rate was increased, whereas cell proliferation was decreased. Compared with that in the normal lung cell line H1688 cells, YAP1 expression was obviously increased in H1975, and over-expression of COPB2 translocated YAP1 from cytoplasm to nuclear, whereas knockdown of COPB2 showed the opposite effect. Overexpression of COPB2 enhanced cell proliferation, tumorigenesis and inhibited cell apoptosis. However, these effects were abolished when down-regulated YAP1 expression on the base of COPB2 over-expression. In conclusion, the increased expression of COPB2 was significantly correlated with the progression of lung adenocarcinoma. Up-regulation of COPB2 inhibited cell apoptosis and promoted cell growth and tumorigenesis through up-regulating YAP1 expression in lung adenocarcinoma.

Nuclear domain 10 components upregulated via interferon during human cytomegalovirus infection potently regulate viral infection

Human cytomegalovirus (HCMV) is a ubiquitous betaherpesvirus that causes life-threatening disease in immunocompromised and immunonaïve individuals. Type I interferons (IFNs) are crucial molecules in the innate immune response to HCMV and are also known to upregulate several components of the interchromosomal multiprotein aggregates collectively referred to as nuclear domain 10 (ND10). In the context of herpesvirus infection, ND10 components are known to restrict gene expression. This raises the question as to whether key ND10 components (PML, Sp100 and hDaxx) act as anti-viral IFN-stimulated genes (ISGs) during HCMV infection. In this study, analysis of ND10 component transcription during HCMV infection demonstrated that PML and Sp100 were significantly upregulated whilst hDaxx expression remained unchanged. In cells engineered to block the production of, or response to, type I IFNs, upregulation of PML and Sp100 was not detected during HCMV infection. Furthermore, pre-treatment with an IFN-β neutralizing antibody inhibited upregulation of PML and Sp100 during both infection and treatment with HCMV-infected cell supernatant. The significance of ND10 components functioning as anti-viral ISGs during HCMV infection was determined through knockdown of PML, Sp100 and hDaxx. ND10 knockdown cells were significantly more permissive to HCMV infection, as previously described but, in contrast to control cells, could support HCMV plaque formation following IFN-β pre-treatment. This ability of HCMV to overcome the potently anti-viral effects of IFN-β in ND10 expression deficient cells provides evidence that ND10 component upregulation is a key mediator of the anti-viral activity of IFN-β.

Expression and Histopathological Significance of Disabled-2 in Aldosterone-Producing Adenoma

The current pathological diagnosis of aldosterone-producing adenoma (APA) is challenging because no histological markers of aldosterone production are available in routine practice. A previous study demonstrated that Disabled-2 (DAB2) is a specific marker of the zona glomerulosa (ZG) in rodents. The aim of the present study was to investigate the significance of immunohistochemical staining to detect DAB2 in the adrenal tissue of patients with APA. We investigated the expression of DAB2 in 36 adrenal glands with APA, 23 adrenal glands with cortisol-producing adenoma (CPA), and 33 adrenal glands with non-functioning adenoma (NFA). Immunohistochemical staining was performed using anti-DAB2 antibodies on paraffin-embedded sections. We analysed the expression of DAB2 semi-quantitatively by scoring staining intensity, and assessed the correlation of this information with the clinical findings. DAB2 mRNA expression in adenoma tissues was evaluated by RT-PCR. DAB2 was highly expressed in the ZG in normal human adrenal glands. DAB2 expression was heterogeneous in APA, with spotted, strong staining noted in most samples (25 of 36 APA). CPA and NFA also exhibited extensive low or moderate DAB2 expression. DAB2 mRNA was significantly increased and positively correlated with CYP11B2 in APA (p<0.05). In APA, the DAB2 score adjusted for tumour volume was positively correlated with plasma aldosterone (p<0.05). Patients with low or moderate DAB2 staining more frequently exhibited high blood pressure and were diagnosed at a younger age compared with patients with high DAB2 staining. The present study clearly demonstrates that DAB2 is a specific marker of the ZG in normal human adrenal glands but that DAB2 immunostaining is not sufficiently powerful for histopathological diagnosis of APA. DAB2 might be involved in excessive aldosterone biosynthesis and correlate with specific clinical characteristics of APA patients.

eIF5A-PEAK1 Signaling Regulates YAP1/TAZ Protein Expression and Pancreatic Cancer Cell Growth

In pancreatic ductal adenocarcinoma (PDAC), mutant KRAS stimulates the translation initiation factor eIF5A and upregulates the focal adhesion kinase PEAK1, which transmits integrin and growth factor signals mediated by the tumor microenvironment. Although eIF5A-PEAK1 signaling contributes to multiple aggressive cancer cell phenotypes, the downstream signaling processes that mediate these responses are uncharacterized. Through proteomics and informatic analyses of PEAK1-depleted PDAC cells, we defined protein translation, cytoskeleton organization, and cell-cycle regulatory pathways as major pathways controlled by PEAK1. Biochemical and functional studies revealed that the transcription factors YAP1 and TAZ are key targets of eIF5A-PEAK1 signaling. YAP1/TAZ coimmunoprecipitated with PEAK1. Interfering with eIF5A-PEAK1 signaling in PDAC cells inhibited YAP/TAZ protein expression, decreasing expression of stem cell-associated transcription factors (STF) including Oct4, Nanog, c-Myc, and TEAD, thereby decreasing three-dimensional (3D) tumor sphere growth. Conversely, amplified eIF5A-PEAK1 signaling increased YAP1/TAZ expression, increasing expression of STF and enhancing 3D tumor sphere growth. Informatic interrogation of mRNA sequence databases revealed upregulation of the eIF5A-PEAK1-YAP1-TEAD signaling module in PDAC patients. Taken together, our findings indicate that eIF5A-PEAK1-YAP signaling contributes to PDAC development by regulating an STF program associated with increased tumorigenicity. Cancer Res; 77(8); 1997-2007. ©2017 AACR.

Metformin inhibited esophageal squamous cell carcinoma proliferation in vitro and in vivo and enhanced the anti-cancer effect of cisplatin

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy with poor prognosis in China. Chemotherapy now is one of the most frequently used treatments for patients with ESCC in middle or late stage, however the effects were often limited by increased chemoresistance or treatment toxicity. So it is urgent to find new drugs to treat ESCC patients. Metformin with low cost and toxicity has proved to have anti-cancer effects in a numerous cancers, while its role and mechanism in ESCC has seldom been studied. In the present study, we found that metformin exhibited not only an anti-proliferation ability in a dose and time dependent manner but also a proapoptosis effect in a dose dependent manner in ESCC cell line KYSE450. Our in vivo experiment also showed that metformin markedly inhibited KYSE450 xenograft tumors growth compared to those treated with normal saline. What’s more, no obvious toxic reactions were observed. To further explore the underlying mechanism, we found that metformin treatment could significantly damp the expression of 4EBP1 and S6K1 in KYSE 450 cells in vitro and in vivo, furthermore, the p-4EBP1 and p-S6K1 expression in KYSE 450 cells were also inhibited greatly in vitro and in vivo. During the therapy of cancer, in order to overcome side effects, combination therapy was often used. In this paper, we demonstrated that metformin potentiated the effects of cisplatin via inhibiting cell proliferation and promoting cell apoptosis. Taken together, metformin owned the potential anti-cancer effect on ESCC in monotherapy or was combined with cisplatin and these results laid solid basis for the use of metformin in ESCC.

RNA splicing and splicing regulator changes in prostate cancer pathology

Changes in mRNA splice patterns have been associated with key pathological mechanisms in prostate cancer progression. The androgen receptor (abbreviated AR) transcription factor is a major driver of prostate cancer pathology and activated by androgen steroid hormones. Selection of alternative promoters by the activated AR can critically alter gene function by switching mRNA isoform production, including creating a pro-oncogenic isoform of the normally tumour suppressor gene TSC2. A number of androgen-regulated genes generate alternatively spliced mRNA isoforms, including a prostate-specific splice isoform of ST6GALNAC1 mRNA. ST6GALNAC1 encodes a sialyltransferase that catalyses the synthesis of the cancer-associated sTn antigen important for cell mobility. Genetic rearrangements occurring early in prostate cancer development place ERG oncogene expression under the control of the androgen-regulated TMPRSS2 promoter to hijack cell behaviour. This TMPRSS2–ERG fusion gene shows different patterns of alternative splicing in invasive versus localised prostate cancer. Alternative AR mRNA isoforms play a key role in the generation of prostate cancer drug resistance, by providing a mechanism through which prostate cancer cells can grow in limited serum androgen concentrations. A number of splicing regulator proteins change expression patterns in prostate cancer and may help drive key stages of disease progression. Up-regulation of SRRM4 establishes neuronal splicing patterns in neuroendocrine prostate cancer. The splicing regulators Sam68 and Tra2β increase expression in prostate cancer. The SR protein kinase SRPK1 that modulates the activity of SR proteins is up-regulated in prostate cancer and has already given encouraging results as a potential therapeutic target in mouse models.

Psip1/p52 regulates posterior Hoxa genes through activation of lncRNA Hottip

Long noncoding RNAs (lncRNAs) have been implicated in various biological functions including the regulation of gene expression, however, the functionality of lncRNAs is not clearly understood and conflicting conclusions have often been reached when comparing different methods to investigate them. Moreover, little is known about the upstream regulation of lncRNAs. Here we show that the short isoform (p52) of a transcriptional co-activator-PC4 and SF2 interacting protein (Psip1), which is known to be involved in linking transcription to RNA processing, specifically regulates the expression of the lncRNA Hottip-located at the 5' end of the Hoxa locus. Using both knockdown and knockout approaches we show that Hottip expression is required for activation of the 5' Hoxa genes (Hoxa13 and Hoxa10/11) and for retaining Mll1 at the 5' end of Hoxa. Moreover, we demonstrate that artificially inducing Hottip expression is sufficient to activate the 5' Hoxa genes and that Hottip RNA binds to the 5' end of Hoxa. By engineering premature transcription termination, we show that it is the Hottip lncRNA molecule itself, not just Hottip transcription that is required to maintains active expression of posterior Hox genes. Our data show a direct role for a lncRNA molecule in regulating the expression of developmentally-regulated mRNA genes in cis.

The cohesion stabilizer sororin favors DNA repair and chromosome segregation during mouse oocyte meiosis

Maintenance and timely termination of cohesion on chromosomes ensures accurate chromosome segregation to guard against aneuploidy in mammalian oocytes and subsequent chromosomally abnormal pregnancies. Sororin, a cohesion stabilizer whose relevance in antagonizing the anti-cohesive property of Wings-apart like protein (Wapl), has been characterized in mitosis; however, the role of Sororin remains unclear during mammalian oocyte meiosis. Here, we show that Sororin is required for DNA damage repair and cohesion maintenance on chromosomes, and consequently, for mouse oocyte meiotic program. Sororin is constantly expressed throughout meiosis and accumulates on chromatins at germinal vesicle (GV) stage/G2 phase. It localizes onto centromeres from germinal vesicle breakdown (GVBD) to metaphase II stage. Inactivation of Sororin compromises the GVBD and first polar body extrusion (PBE). Furthermore, Sororin inactivation induces DNA damage indicated by positive γH2AX foci in GV oocytes and precocious chromatin segregation in MII oocytes. Finally, our data indicate that PlK1 and MPF dissociate Sororin from chromosome arms without affecting its centromeric localization. Our results define Sororin as a determinant during mouse oocyte meiotic maturation by favoring DNA damage repair and chromosome separation, and thereby, maintaining the genome stability and generating haploid gametes.

Suppression of LIM and SH3 Domain Protein 1 (LASP1) Negatively Regulated by Androgen Receptor Delays Castration Resistant Prostate Cancer Progression

BACKGROUND

LIM and SH3 domain protein 1 (LASP1) has been implicated in several human malignancies and has been shown to predict PSA recurrence in prostate cancer. However, the anti-tumor effect of LASP1 knockdown and the association between LASP1 and the androgen receptor (AR) remains unclear. The aim of this study is to clarify the significance of LASP1 as a target for prostate cancer, and to test the effect of silencing LASP1 in vivo using antisense oligonucleotides (ASO).

METHODS

A tissue microarray (TMA) was performed to characterize the differences in LASP1 expression in prostate cancer treated after hormone deprivation therapy. Flow cytometry was used to analyze cell cycle. We designed LASP1 ASO for knockdown of LASP1 in vivo studies.

RESULTS

The expression of LASP1 in TMA was increased after androgen ablation and persisted in castration resistant prostate cancer (CRPC). Also in TMA, compared with LNCaP cell, LASP1 expression is elevated in CRPC cell lines (C4-2 and VehA cells). Interestingly, suppression of AR elevated LASP1 expression conversely, AR activation decreased LASP1 expression. Silencing of LASP1 reduced cell growth through G1 arrest which was accompanied by a decrease of cyclin D1. Forced overexpression of LASP1 promoted cell cycle and induced cell growth which was accompanied by an increase of cyclin D1. Systemic administration of LASP1 ASO with athymic mice significantly inhibited tumor growth in CRPC xenografts.

CONCLUSIONS

These results indicate that LASP1 is negatively regulated by AR at the transcriptional level and promotes tumor growth through induction of cell cycle, ultimately suggesting that LASP1 may be a potential target in prostate cancer treatment. Prostate 77:309-320, 2017. © 2016 Wiley Periodicals, Inc.

DLG1 polarity protein expression associates with the disease progress of low-grade cervical intraepithelial lesions

Human Discs large tumour suppressor (DLG1) participates in regulating cell polarity and proliferation, suggesting an important connection between epithelial organization and cellular growth control. However, it was demonstrated that DLG1 could acquire oncogenic attributes in some specific contexts. In this work, we evaluated the expression of DLG1 and its contribution to the progress of cervical lesions in order to investigate a potential role of this polarity protein in human oncogenic processes. We analyzed cervical biopsies from women with low-grade squamous intraepithelial lesion (LSIL) diagnosis (n=30), for DLG1 expression by immunohistochemistry. These results were correlated with the clinical monitoring of the patients during a 24-month follow-up period. Our data indicate that while all LSIL patients with a DLG1 staining pattern similar to normal tissues are significantly more likely to regress (n=23, Pattern I), all LSIL biopsy specimens showing a diffuse and intense DLG1 staining likely progress to high-grade lesions (n=4, Pattern II). Finally, all persistent LSIL analyzed showed an undetermined DLG1 staining, with a diffuse distribution without a strong intensity (n=3, Pattern III). We found a significant association between the expression pattern of DLG1 and the evolution of the lesion (p<0.00001). This work contributes to the knowledge of DLG1 biological functions, suggesting that its expression may have an important role in the progression of early dysplastic cervical lesions, giving prognostic information.

Nonstructural Protein 11 of Porcine Reproductive and Respiratory Syndrome Virus Suppresses Both MAVS and RIG-I Expression as One of the Mechanisms to Antagonize Type I Interferon Production

Type I interferons (IFN-α/β) play a key role in antiviral defense, and porcine reproductive and respiratory syndrome virus (PRRSV) is known to down-regulate the IFN response in virus-infected cells and pigs. In this study, we showed that the overexpression of nsp11 of PRRSV induced a strong suppression of IFN production. Nsp11 suppressed both IRF3 and NF-κB activities when stimulated with a dsRNA analogue and TNF-α, respectively. This suppression was RLR dependent, since the transcripts and proteins of MAVS and RIG-I, two critical factors in RLR-mediated pathway, were both found to be reduced in the presence of overexpressed nsp11. Since nsp11 is an endoribonuclease (EndoU), the structure function relationship was examined using a series of nsp11 EndoU mutant plasmids. The mutants that impaired the EndoU activity failed to suppress IFN and led to the normal expression of MAVS. Seven single amino acid substitutions (4 in subdomain A and 3 in subdomain B) plus one insertion (frame-shift in nsp11) were then introduced into PRRSV infectious cDNA clones to generate nsp11 mutant viruses. Unfortunately, all EndoU knock-out nsp11 mutant viruses appeared replication-defective and no progenies were produced. Three mutations in EndoU subdomain A expressed the N and nsp2/3 proteins but their infectivity diminished after 2 passages. Taken together, our data show that PRRSV nsp11 endoribonuclease activity is critical for both viral replication and IFN antagonism. More importantly, the endoribonuclease activity of nsp11 demonstrates the substrate specificity towards MAVS and RIG-I (transcripts and proteins) over p65 and IRF3 in the context of gene transfection and overexpression. This is likely a mechanism of nsp11 suppression of type I IFN production.

Amplified in Breast Cancer Regulates Transcription and Translation in Breast Cancer Cells

Background

Control of mRNA translation is fundamentally altered in cancer. Insulin-like growth factor-I (IGF-I) signaling regulates key translation mediators to modulate protein synthesis (e.g. eIF4E, 4E-BP1, mTOR, and S6K1). Importantly the Amplified in Breast Cancer (AIB1) oncogene regulates transcription and is also a downstream mediator of IGF-I signaling.

Materials and Methods

To determine if AIB1 also affects mRNA translation, we conducted gain and loss of AIB1 function experiments in estrogen receptor alpha (ERα)⁺ (MCF-7L) and ERα^- (MDA-MB-231, MDA-MB-435 and LCC6) breast cancer cells.

Results

AIB1 positively regulated IGF-I-induced mRNA translation in both ERα⁺ and ERα^- cells. Formation of the eIF4E-4E-BP1 translational complex was altered in the AIB1 ERα⁺ and ERα^- knockdown cells, leading to a reduction in the eIF4E/4E-BP1 and eIF4G/4E-BP1 ratios. In basal and IGF-I stimulated MCF-7 and LCC6 cells, knockdown of AIB1 decreased the integrity of the cap-binding complex, reduced global IGF-I stimulated polyribosomal mRNA recruitment with a concomitant decrease in ten of the thirteen genes tested in polysome-bound mRNAs mapping to proliferation, cell cycle, survival, transcription, translation and ribosome biogenesis ontologies. Specifically, knockdown of AIB1 decreased ribosome-bound mRNA and steady-state protein levels of the transcription factors ERα and E2F1 in addition to reduced ribosome-bound mRNA of the ribosome biogenesis factor BYSL in a cell-line specific manner to regulate mRNA translation.

Conclusion

The oncogenic transcription factor AIB1 has a novel role in the regulation of polyribosome recruitment and formation of the translational complex. Combinatorial therapies targeting IGF signaling and mRNA translation in AIB1 expressing breast cancers may have clinical benefit and warrants further investigation.

Dynamic Regulation of Hypothalamic DMXL2, KISS1, and RFRP Expression During Postnatal Development in Non-Human Primates

The neurobiological mechanism of puberty onset in primates is currently only partly understood. A recent study reported an important role of Dmx-like 2 (DMXL2), a gene encoding rabconnectin-3α vesicular protein, in human subjects with mental retardation and neuroendocrine impairment of reproduction. To further characterize the potential role of DMXL2 in the regulation of reproduction, we analyzed the expression of DMXL2 in hypothalami of newborn, infantile, juvenile, pubertal, and postpubertal female and male common marmoset monkeys. Additionally, as the relative hypothalamic levels of gonadotropin-inhibitory hormone (GnIH) transcript during postnatal development are unknown in primates, we also quantified messenger RNA (mRNA) levels of RFRP, a gene encoding GnIH. Moreover, the transcript levels of kisspeptin, a well-known regulator of the hypothalamic neurohormonal axis controlling reproduction, were also checked. Transcript and protein levels of DMXL2 and Kiss1 transcript levels increase from the newborn to the infantile and from the juvenile (prepubertal) to the pubertal and the postpubertal period. We also noted a clear upsurge in RFRP transcript levels in the prepubertal period. In conclusion, the hypothalamic expressions of Kiss1 and DMXL2 mRNA increase during infantile, pubertal, and adult stages compared to newborn and juvenile stages in common marmoset monkeys. In contrast, the expression of RFRP mRNA upsurges in juvenile monkeys. Further mechanistic studies are needed to characterize the potential inhibitory role of the GnIH-GPR147 signaling in the prepubertal period and the role of DMXL2 in the molecular cascade regulating the neuroendocrine reproductive axis in primates.

SORORIN and PLK1 as potential therapeutic targets in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive type of cancer of the thoracic cavity commonly associated with asbestos exposure and a high mortality rate. There is a need for new molecular targets for the development of more effective therapies for MPM. Using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and an RNA interference-based screening, we examined the SORORIN gene as potential therapeutic targets for MPM in addition to the PLK1 gene, which is known for kinase of SORORIN. Following in vitro investigation of the effects of target silencing on MPM cells, cell cycle analyses were performed. SORORIN expression was analyzed immunohistochemically using a total of 53 MPM samples on tissue microarray. SORORIN was found to be overexpressed in the majority of clinical MPM samples and human MPM cell lines as determined by qRT-PCR. Gene suppression of each SORORIN and PLK1 led to growth inhibition in MPM cell lines. Knockdown of SORORIN showed an increased number of G2M-phase population and a larger nuclear size, suggesting mitotic arrest. High expression of SORORIN (SORORIN-H) was found in 50.9% of all the MPM cases, and there is a tendency towards poorer prognosis for the SORORIN-H group but the difference is not significant. Suppression of SORORIN with PLK1 inhibitor BI 6727 showed a combinational growth suppressive effect on MPM cell growth. Given high-dose PLK1 inhibitor induced drug-related adverse effects in several clinical trials, our results suggest inhibition SORORIN-PLK1 axis may hold promise for the treatment of MPMs.

SLC7A5 Functions as a Downstream Target Modulated by CRKL in Metastasis Process of Gastric Cancer SGC-7901 Cells

SLC7A5, who is also named LAT-1, has been validated as a promoter regulated by miRNA-126 in our previous research for gastric cancer cells. However, the mechanisms driving SLC7A5 to affect the bio-function of gastric cancer cells are unclear, remaining us lots of to elucidate. The aim of this study is to investigate the regulating effect of CRKL, one of the critical genes involving with gastric cancer progression, on SLC7A5 expression. By studying the gastric cancer cell lines and clinical pathological specimens, we found that the expression of SLC7A5 was significantly correlated to CRKL. By depleting CRKL in gastric cancer SGC-7901 cells, the SLC7A5 expression was impaired, and the invasion and migration of SGC-7901 cells were suppressed. Ectopic expression of SLC7A5 could drastically rescue the phenotypes induced by CRKL depletion in this study. Accordingly, we conclude that SLC7A5 functions as a promoter in gastric cancer metastasis, and CRKL could be one of its regulators modulating the expression of SLC7A5 and consequentially affect the metastatic feature of SGC-7901 cells. The findings in this study indicate a regulation relationship between CRKL and SLC7A5, and provide useful evidence for gastric cancer therapeutic strategies.

miR-199a-3p inhibits cell proliferation and induces apoptosis by targeting YAP1, suppressing Jagged1-Notch signaling in human hepatocellular carcinoma

BACKGROUND

miR-199a-3p was significantly downregulated in the majority of human hepatocellular carcinoma (HCC) tissues and HCC cell lines. Yes associated protein 1 (YAP1) was overexpressed in human HCC, which promoted HCC development and progression by upregulating Jagged1 and activating the Notch pathway. We searched potential targets of miR-199a-3p with DIANA, TargetScan and PicTar tools, and found that YAP1 is one of the potential targets. Based on these findings, we speculated that miR-199a-3p might suppress HCC growth by targeting YAP1, downregulating Jagged1 and suppressing the Notch pathway.

RESULTS

We determined the expression of miR-199a-3p and YAP1 by quantitative Real-Time PCR (qRT-PCR) and western blot assays, respectively, and found downregulation of miR-199a-3p and upregulation of YAP1 in HCC cell lines. Cell proliferation and apoptosis assays showed that miR-199a-3p suppresses HCC cell proliferation and promotes apoptosis, and knockdown of YAP1 has similar role. Furthermore, we verified that miR-199a-3p can directly target YAP1. We further investigated and confirmed that miR-199a-3p and YAP1 regulate HCC cell proliferation and apoptosis through Jagged1-Notch signaling.

CONCLUSION

miR-199a-3p targets YAP1, downregulates Jagged1 and suppresses the Notch signaling to inhibit HCC cell proliferation and promote apoptosis. These findings provide new insights into the mechanism by which miR-199a-3p suppresses HCC cell proliferation and induces apoptosis.

MiR-339 and especially miR-766 reactivate the expression of tumor suppressor genes in colorectal cancer cell lines through DNA methyltransferase 3B gene inhibition

It is observed that upregulation of DNMT3B enzyme in some cancers, including colon cancer, could lead to silencing of tumor suppressor genes. MiR-339 and miR-766 have been predicted to target 3'UTR of DNMT3B gene. Luciferase reporter assay validated that individual and co-transfection of miR-766 and miR-339 into the HEK293T cell reduced luciferase activity to 26% ± 0.41%, 43% ± 0.42 and 64% ± 0.52%, respectively, compared to the control (P < 0.05). Furthermore, transduction of miR-339 and miR-766 expressing viruses into colon cancer cell lines (SW480 and HCT116) decreased DNMT3B expression (1.5, 3-fold) and (3, 4-fold), respectively. In addition, DNA methylation of some tumor suppressor genes decreased. Expression of these genes such as SFRP1 (2 and 1.6-fold), SFRP2 (0.07 and 4-fold), WIF1 (0.05 and 4-fold), and DKK2 (2 and 4-fold) increased in SW-339 and SW-766 cell lines; besides, expression increments for these genes in HCT-339 and HCT-766 cell lines were (2.8, 4-fold), (0.005, 1.5-fold), (1.7 and 3-fold) and (0.04, 1.7-fold), respectively. Also, while in SW-766, cell proliferation reduced to 2.8% and 21.7% after 24 and 48 hours, respectively, SW-339 showed no reduced proliferation. Meanwhile, HCT-766 and HCT-339 showed (3.5%, 12.8%) and (18.8%, 33.9%) reduced proliferation after 24 and 48 hours, respectively. Finally, targeting DNMT3B by these miRs, decreased methylation of tumor suppressor genes such as SFRP1, SFRP2, WIF1 and DKK2 in the mentioned cell lines, and returned the expression of these tumor suppressor genes which can contribute to lethal effect on colon cancer cells and reducing tumorigenicity of these cells.