BackgroundA growing amount of evidence has indicated that PSAT1 is an oncogene that plays an important role in cancer progression and metastasis. In this study, we explored the expression and function of PSAT1 in estrogen receptor (ER)-negative breast cancer.MethodThe expression level of PSAT1 in breast cancer tissues and cells was analyzed using real-time-PCR (RT-PCR), TCGA datasets or immunohistochemistry (IHC). The overall survival of patients with ER-negative breast cancer stratified by the PSAT1 expression levels was evaluated using Kaplan-Meier analysis. The function of PSAT1 was analyzed using a series of in vitro assays. Moreover, a nude mouse model was used to evaluate the function of PSAT1 in vivo. qRT-PCR and western blot assays were used to evaluate gene and protein expression, respectively, in the indicated cells. In addition, we demonstrated that PSAT1 was activated by ATF4 by chromatin immunoprecipitation (ChIP) assays.ResultsmRNA expression of PSAT1 was up-regulated in ER-negative breast cancer. A tissue microarray that included 297 specimens of ER-negative breast cancer was subjected to an immunohistochemistry assay, which demonstrated that PSAT1 was overexpressed and predicted a poor clinical outcome of patients with this disease. Our data showed that PSAT1 promoted cell proliferation and tumorigenesis in vitro and in vivo. We further found that PSAT1 induced up-regulation of cyclin D1 via the GSK3β/β-catenin pathway, which eventually led to the acceleration of cell cycle progression. Furthermore, ATF4 was also overexpressed in ER-negative breast cancers, and a positive correlation between the ATF4 and PSAT1 mRNA levels was observed in ER-negative breast cancers. We further demonstrated that knockdown of ATF4 by siRNA reduced PSAT1 expression. Finally, chromatin immunoprecipitation (ChIP) assays showed that PSAT1 was a target of ATF4.ConclusionsPSAT1, which is overexpressed in ER-negative breast cancers, is activated by ATF4 and promotes cell cycle progression via regulation of the GSK3β/β-catenin/cyclin D1 pathway.Electronic supplementary materialThe online version of this article (doi: 10.1186/s13046-017-0648-4) contains supplementary material, which is available to authorized users.

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Neuropathic pain (NP) is a frustrating and burdensome problem. Current treatments for NP have unendurable side effects and/or questionable efficacy, and once these therapies are stopped, the symptoms often return. Thus, novel drugs are needed to enhance the effectiveness of treatments for NP. One novel target for pain treatments is adenosine monophosphate-activated protein kinase (AMPK), which regulates a variety of cellular processes, including protein translation, which is considered to be affected in NP. Metformin is a widely available drug that possesses the ability to activate AMPK. The signal transducer and activator of transcription 3 (STAT3) pathway plays an important role in neuroinflammation. The present study investigated the analgesic effect of metformin on NP induced by chronic constriction injury (CCI), and the influence of metformin on the expression of AMPK and STAT3 in the spinal dorsal horn (SDH). In CCI rats, paw withdrawal latencies in response to thermal hyperalgesia were significantly shorter, while phosphorylated (p)-AMPK was expressed at lower levels and p-STAT3 was expressed at higher levels in the SDH. Administering intraperitoneal injections of metformin (200 mg/kg) for 6 successive days activated AMPK and suppressed the expression of p-STAT3, in addition to reversing hyperalgesia. Finally, metformin inhibited the activation of microglia and astrocytes in the SDH, which may explain how it alleviates NP.

BackgroundAs biomarkers, DNA methylation is used to detect colorectal cancer (CRC) and make assessment of CRC prognosis. The published findings showed the association between the methylation of SFRP1, SFRP2, and WIF1, located in the Wnt signaling pathway, and the prognosis of CRC were not consistent. Our study aimed to explore the potential possibility of SFRP1, SFRP2, and WIF1 concomitant promoter methylation as prognostic biomarkers of postoperative CRC patients.MethodsAs a total of 307 sporadic postoperative CRC patients were followed up, we detected SFRP1, SFRP2, and WIF1 methylation obtained from tumor tissues and adjacent non-tumor tissues respectively on the basis of methylation-sensitive high resolution melting analysis. Univariate and multivariate Cox regressions were carried out so as to assess the potential possibility of SFRP1, SFRP2, and WIF1 promoter methylation as predictors of prognosis. Confounders in our study were controlled by Propensity Score (PS) analysis.ResultsThe SFRP1, SFRP2, and WIF1 methylation levels in tumor tissues were significantly higher than that in adjacent non-tumor tissues (P < 0.001). SFRP2 hypermethylation was significantly associated with a favorable clinical outcome at the hazard ratio (HR) of 0.343 [95% confidence intervals (CI): 0.164–0.718, P = 0.005] and 0.410 (95% CI: 0.200–0.842, P = 0.015) in multivariate Cox regression and PS analysis, respectively. Co-hypermethylation of SFRP1 and SFRP2 was significantly associated with a favorable clinical outcome at the HR of 0.333 (95% CI: 0.159–0.694, P = 0.003) and 0.398 (95% CI: 0.192–0.821, P = 0.013) in multivariate Cox regression and PS analysis, respectively. Co-hypermethylation of SFRP1, SFRP2 and WIF1 was significantly associated with a favorable clinical outcome at the HR of 0.326 (95% CI: 0.117–0.908, P = 0.032) and 0.401 (95% CI: 0.146–1.106, P = 0.077) in multivariate Cox regression and PS analysis, respectively.ConclusionsSFRP1, SFRP2, and WIF1 were frequently hypermethylated in CRC tumor tissues. It was apparent that the promoter hypermethylation of SFRP2 and co-hypermethylation of SFRP1 and SFRP2 might be considered as independent prognostic predictors for survival advantage of postoperative CRC patients.

Background. Hedysarum multijugum Maxim.-Chuanxiong rhizoma compound (HCC) is a common herbal formula modified from Buyang Huanwu decoction. Clinical trials have demonstrated its therapeutic potential for ischemic stroke (IS). However, the mechanism of HCC remains unclear. Methods. The HCC’s components were collected from the TCMSP database and TCM@Taiwan database. After that, the HCC’s compound targets were predicted by PharmMapper. The IS-related genes were obtained from GeneCards, and OMIM and the protein-protein interaction (PPI) data of HCC’s targets and IS genes were obtained from the String database. After that, the DAVID platform was applied for Gene Ontology (GO) enrichment analysis and pathway enrichment analysis and the Cytoscape 3.7.2 was utilized to construct and analyze the networks. Finally, a series of animal experiments were carried out to validate the prediction results of network pharmacology. The expressions of GRP78, p-PERK, and CHOP proteins and mRNAs in different time periods after HCC intervention were detected by Western blot, immunohistochemistry, and RT-qPCR. Results. A total of 440 potential targets and 388 IS genes were obtained. The results of HCC-IS PPI network analysis showed that HCC may regulate IS-related targets (such as ALB, AKT1, MMP9, IGF1, and CASP3), biological processes (such as endoplasmic reticulum stress, inflammation modules, hypoxia modules, regulation of neuronal apoptosis and proliferation, and angiogenesis), and signaling pathways (such as PI3K-Akt, FoxO, TNF, HIF-1, and Rap1 signaling). The animal experiments showed that HCC can improve the neurobehavioral scores and protect the neurons of IS rats ( P < 0.05 ). HCC inhibited the expression of p-PERK in the PERK pathway from 12 h after surgery, significantly promoted the expression of GRP78 protein, and inhibited the expression of CHOP protein after surgery, especially at 24 h after surgery ( P < 0.05 ). The results of RT-qPCR showed that HCC can significantly reduce the expression of CHOP mRNA in the neurons in the CA1 region of the hippocampus 72 h after MCAO ( P < 0.05 ). Conclusion. HCC may achieve a role in the treatment of IS by intervening in a series of targets, signaling pathways, and biological processes such as inflammation, oxidative stress, endoplasmic reticulum stress, and angiogenesis.

Calcification is a major risk factor for vascular integrity. This pathological symptom and the underlying mechanisms in hypoxic pulmonary artery hypertension remain elusive. Here we report that pulmonary vascular medial calcification is elevated in pulmonary artery hypertension models as a result of an osteoblastic phenotype change of pulmonary arterial smooth muscle cells induced by hypoxia. Notably, inhibiting store-operated calcium channels significantly decreased osteoblastic differentiation and calcification of pulmonary arterial smooth muscle cells under hypoxia. We identified granzyme B, a major constituent of cytotoxic T lymphocytes/natural killer cell granules involved in apoptosis, as the main regulator of pulmonary arterial calcification. Overexpression of granzyme B blocked the mineralization through its effect on store-operated calcium channels in cultured pulmonary arterial smooth muscle cells under hypoxic conditions. Mice with overexpression of granzyme B exposed to hypoxia for 3 weeks showed attenuated vascular calcification and pathological progression of hypoxic pulmonary arterial hypertension. Our findings emphasize the central function of granzyme B in coordinating vascular calcification in hypoxic pulmonary arterial hypertension.

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The function of Fer-1 like family member 4 (FER1L4) in human pan-cancer is unknown.Expression of FER1L4 in tumor tissues and nontumor tissues, upstream regulation of FER1L4, and the relationship between its expression with prognosis and chemoresistance were examined by The Cancer Genome Atlas and Gene Expression Omnibus databases.Next, these results were validated in breast tumor and paired nontumor tissues in our cohort. FER1L4 expression is higher in tumor tissues compared with the adjacent nontumor tissues. High FER1L4 expression is associated with worse disease outcomes.Hypomethylation and H3K4me3 accumulation in FER1L4 promoter locus activate its transcriptional expression. Moreover, FER1L4 may trigger chemoresistance in human cancer. Gene Ontology enrichment analysis revealed that FER1L4 may be involved in processes associated with tumorigenesis. These results indicated that FER1L4 may act as an oncogenic driver and it may be a potential therapy target in human cancer. K E Y W O R D SFER1L4, long noncoding RNA, methylation, pan-cancer, survival