HIF1A-AS2 Promotes the Proliferation and Metastasis of Gastric Cancer Cells Through miR-429/PD-L1 Axis.

BACKGROUND: Gastric cancer (GC) is a common leading cause of cancer-related mortality of all malignancies. LncRNA hypoxia-inducible factor-1 alpha antisense RNA-2 (HIF1A-AS2) has been identified to involve in the development of GC. Therefore, we further explored the detailed molecular mechanism of HIF1A-AS2 in GC progression. METHODS: The expression of HIF1A-AS2, microRNA-429 (miR-429), and programmed cell death ligand 1 (PD-L1) was measured using quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell proliferation, migration, and invasion abilities were detected by Cell Counting Kit-8 (CCK-8) or transwell assay. The interaction between miR-429 and HIF1A-AS2 or PD-L1 was confirmed by luciferase reporter assay. Murine xenograft model was established to investigate the role of HIF1A-AS2 in vivo. RESULTS: HIF1A-AS2 was elevated in GC tissues and cell lines. Functional experiments showed that HIF1A-AS2 knockdown inhibited GC cell proliferation, migration, and invasion in vitro, as well as hindered tumor growth in vivo. Moreover, HIF1A-AS2 directly bound to miR-429 based on bioinformatics prediction and luciferase assay, and inhibition of miR-429 abolished the effects of HIF1A-AS2 knockdown on GC cells. Furthermore, miR-429 directly targeted PD-L1, and overexpression of miR-429 suppressed GC tumorigenesis via PD-L1. Besides that, PD-L1 also performed an oncogenic role in GC cell proliferation and metastasis. Additionally, HIF1A-AS2 could indirectly regulate PD-L1 expression via sponging miR-429. CONCLUSION: HIF1A-AS2 is a dependable predictor of malignancy and prognosis in GC and functions as an oncogene to promote GC cell proliferation and metastasis by regulating miR-429/PD-L1 axis, indicating a new insight into the search for novel biomarkers and therapeutic strategies.

HIF­3α affects preeclampsia development by regulating EVT growth via activation of the Flt­1/JAK/STAT signaling pathway in hypoxia.

Preeclampsia (PE) is a common obstetric disease occurring after 20 weeks of gestation. Hypoxia­inducible factor (HIF)­3α potentially functions as a regulatory factor in PE development, however its specific molecular mechanism remains to be elucidated. The present study aimed to investigate the function of HIF­3α in trophoblast cell line HTR­8/SVneo, to provide a better understanding of the pathology and treatment of PE. Normal and PE placentas were obtained from pregnant women. HTR8/SVneo cells were cultured under the condition of normoxia or hypoxia, pretreated with or without AG490, then transfected with HIF­3α. The gene expression levels of HIF­3α and Fms like tyrosine kinase receptor (Flt) 1 extracted from the placentas and cells were detected by reverse transcription­quantitative PCR, and the expression levels of proteins and Janus kinase signal transducer and activator of transcription (JAK/STAT) phosphorylation were detected by western blot analysis. Viability and apoptosis of the treated cells were assessed by MTT and flow cytometry. The results demonstrated that HIF­3α and Flt­1 gene expression levels of PE placentas were reduced compared with normal placentas. Under a hypoxic environment, the expression levels of HIF­3α and Flt­1, the phosphorylation of JAK/STAT and the cell viability of HTR8/SVneo cells were increased at first and then reduced, whereas cell apoptosis was promoted over time. Under chronic hypoxia, the expression levels of HIF­3α and Flt­1, JAK/STAT pathway phosphorylation and cell viability of AG490­treated HTR8/SVneo cells were reduced, but cell apoptosis was promoted. However, the upregulation of HIF­3α in HTR8/SVneo cells markedly reversed the effects of AG490 on the cells under hypoxia. Thus, the present study preliminarily demonstrated that HIF­3α was involved in PE development by regulating extravillous cytotrophoblast growth via Flt­1 and the JAK/STAT signaling pathway.

MicroRNA­195 suppresses rectal cancer growth and metastasis via regulation of the PI3K/AKT signaling pathway.

MicroRNAs (miRNAs) play a vital role in the progression of cancer, however, only limited data on miRNAs in rectal cancer are available. The aim of the present study was to investigate whether miR­195 could inhibit the progression of rectal cancer. The miR­195 mimic was transfected into 2 types of human rectal cancer cells (SW837 and SW1463). Cell viability and apoptosis were analyzed by Cell Counting Kit­8 (CCK­8) assay and flow cytometry, and cell migration and invasion were assessed by scratch test and Transwell assay. The results revealed that insulin­like growth factor 1 (IGF1) was predicted as a potential target of miR­195 by Targetscan7.2, and the result was verified by dual­luciferase reporter assay. The co­transfection of IGF1 was performed to confirm the underlying mechanism of tumor suppressor of miR­195 in rectal cancer. The activation of PI3K/AKT signaling was determined by western blotting. The levels of miR­195 in SW837 and SW1463 cells were revealed to be lower than in human rectal mucosa epithelial cells. After the transfection with miR­195, the cell viability was decreased, while the apoptosis was significantly increased (SW837: 5.21% vs. 20.96%; SW1463: 4.19% vs. 25.22%). Moreover, cell migration and invasion were significantly inhibited in the mimic group. miR­195 specifically targeted IGF1, however, the co­transfection of IGF1 could partially reverse the inhibitory effects of miR­195 on rectal cancer cells. It was also determined that the phosphorylation of PI3K and AKT were significantly inhibited in the mimic group. The tumor suppressive ability of miR­195 in rectal cancer cell proliferation and metastasis was mediated by blocking IGF1 expression and inhibiting the PI3K/AKT pathway.

Relationship between the expressions of PD-L1 and tumour-associated fibroblasts in gastric cancer.

Previous studies have focused on the changes of tumour cells in immune escape, and less is known about the effect of tumour microenvironment (TME) on immune escape. Tumour-associated fibroblasts (TAF) is an important part of the TME and has special physiological and biochemical characteristics, but the specific mechanism has not been clarified. In order to investigate the effect of TAF on the expression of PD-L1 in gastric cancer cells, gastric cancer cell lines MNK45, SGC7901 were non-contact co-culturing with TAF 1, 3 and 7 d via transwell. PD-L1 mRNA and protein expression were detected using qRT-PCR and FCM. Then, 95 cases of gastric cancer tissues were selected and evaluated PD-L1 and TAF expressions by immunohistochemical examination. The results showed that the mRNA and protein expression of PD-L1 in the experiment group were significantly higher than that in the control group. PD-L1 expression was associated with massive lymphocyte infiltration, diffuse/mixed histology and intratumoral TAFs in gastric cancers. In conclusion, TAFs promoted the growth in gastric cancer cell lines by increased the PD-L1 expression.

Androgen attenuates antitumor effects of gastric cancer cells by bone marrow mesenchymal stem cells via restricting the JNK signaling activation.

BACKGROUND: Researches on bone marrow mesenchymal stem cells (BMMSCs) have generated controversial results in tumor research. In the present study, we aimed to explore the functions of BMMSCs on gastric cancer and the possible mechanism in a mimicking microenvironment of the stomach. METHODS: Transwell co-cultured system was used to co-culture BMMSCs and gastric cancer SGC-7901 cells. In some experiments, androgen and its antagonist were added into the cells as required. Cell viability, cell apoptosis, mRNA and protein expressions of apoptosis- and JNK signaling- associated genes were respectively determined by performing cell counting kit-8, flow cytometry, quantitative real-time PCR and western blot. RESULTS: Androgen contributed to the growth of BMMSCs and SGC-7901 cells. In co-cultured system, BMMSCs not only suppressed SGC-7901 cell viability, induced cell apoptosis and promoted tumor necrosis factor (TNF)-α release, but also regulated the level of Bax/Bcl-2 and elevated the expressions of phosphorylation (p)-JNK and p53. After adding androgens, the anti-tumor effects of BMMSCs were weakened. Meanwhile, the antagonists of androgens could partially recover BMMSCs in vitro inhibitory effects on gastric cancer cells by activation of JNK signaling. CONCLUSIONS: This study demonstrated the important roles of BMMSCs on the growth and apoptosis of gastric cancer cells in vitro. Additionally, in the mimicking microenvironment of the stomach, androgen weakened the antitumor effects of BMMSCs by limiting JNK signaling activation, suggesting that androgen antagonist may be a promising adjuvant drug to BMMSCs in gastric cancer therapy.

Protective effect of baicalin on fetal lung development in a rabbit model of congenital diaphragmatic hernia.

Bacalin has been reported to improve fetal lung growth by increasing fetal lung surfactant phospholipids. Therefore, the present study evaluated the effect of transplacental treatment of baicalin during lung development in rabbits with congenital diaphragmatic hernia (DH) rabbit. DH was induced in fetal rabbit on gestational day 23 and baicalin injections were administered daily until term period. Fetal survival rate, body weight and lung-to-body weight ratio (LBWR) were subsequently measured, and the expression of surfactant protein B (SPB) and Ki-67, and morphometry analysis was determined in lung tissues. It was observed that in baicalin treated group the fetal survival rate and LBWR were decreased compared with the control without DH group. Lung morphometry results suggested that treatment with baicalin did not significantly ameliorate congenital DH, and adventitial and medial thickness were similar to those in the control groups, and less muscularization of vessels measuring 30-60 µm. Furthermore, baicalin treatment did not markedly affect the expressions of Ki-67 and SPB in fetuses with DH. Baicalin was demonstrated to improve the morphology of lung in rabbits; however, as it did not induce marked airway changes this present study suggests that baicalin is not suitable for the management of congenital DH.

Upregulated miR-222 targets BCL2L11 and promotes apoptosis of mesenchymal stem cells in preeclampsia patients in response to severe hypoxia.

Abnormal maternal trophoblast invasion is a common finding in preeclampsia pregnancy. A hypoxic environment develops in the placenta after the 10th week of pregnancy and exerts a major influence over trophoblast activity. In the present study, we investigated expression of miR-222 and apoptosis-related BCL2L11 in preeclampsia placenta and in primary placenta mesenchymal stem cells (MSCs) under hypoxia. The results demonstrate that miR-222 is upregulated in the placenta of preeclampsia patients, along with the downregulation of BCL2L11 in both mRNA and protein levels. In vitro results demonstrate that miR-222 is upregulated either in preeclampsia placenta tissues or in the MSCs under hypoxia. Western blotting showed downregulation of BCL2L11 in the trophoblasts under hypoxia, along with an increased MSC apoptosis. miR-222 was also confirmed to downregulate BCL2L11 expression via targeting the 3' untranslated region (UTR) of the BCL2L11 gene. miR-222 inhibitor transfection markedly ameliorated expression and transcriptional activity of BCL2L11. Altogether, the present study found that upregulation of miR-222 promotes apoptosis of mesenchymal stem cells in preeclampsia patients in response to hypoxia, via targeting BCL2L11. This suggests that a key regulatory role of miR-222 is in preeclampsia progression.

Preventing necrotizing enterocolitis by food additives in neonates: A network meta-analysis revealing the efficacy and safety.

BACKGROUND: Necrotizing enterocolitis (NEC) is a serious multifactorial gastrointestinal disease which is often discovered in premature infants. Various additives have been used to prevent NEC; yet, their relative efficacy and safety remain disputed. This study aims to compare the efficacy and safety of 5 food additives, namely, probiotics, probiotics + fructo-oligosaccharides, pentoxifylline, arginine, and lactoferrin in preventing NEC in neonates. METHODS: Embase, PubMed, and Cochrane Library had been searched for all eligible randomized control trials. Odds ratios (ORs) were estimated for dichotomous data and mean differences with 95% credible intervals (CrIs) were estimated for continuous data. Surface under the cumulative ranking curve was used to rank efficacy and safety of the prevention methods on each endpoint. RESULTS: A total of 27 eligible studies with 4649 preterm infants were included in this network meta-analysis (NMA), and the efficacy and safety of 5 food additives were evaluated. Probiotic and arginine exhibited better preventive efficacy compared with placebo (OR = 0.50, 95% CrIs: 0.32-0.73; OR = 0.30, 95% CrIs: 0.12-0.73, respectively). Only probiotic achieved a considerable decrease in the risk of mortality compared to placebo (OR = 0.68, 95% CrIs: 0.46-0.98). NEC patients with lactoferrin appeared to have lower incidence of sepsis than those of placebo (OR = 0.13, 95% CrIs: 0.03-0.61) or probiotic (OR = 0.18, 95% CrIs: 0.03-0.83). CONCLUSION: Based on this NMA, probiotics had the potential to be the most preferable additive, since it exhibited a significant superiority for NEC and mortality as well as a relatively balanced performance in safety.