Magnolol and Honokiol Inhibited the Function and Expression of BCRP with Mechanism Exploration

Breast cancer resistance protein (BCRP), one of the ATP-binding cassette (ABC) transporters, was associated with the multidrug resistance (MDR) of chemotherapy. Magnolol (MN) and honokiol (HK) are major bioactive polyphenols of Magnolia officinalis. This study investigated the effects of MN and HK on the function and expression of BCRP for the purpose of developing BCRP inhibitor to overcome MDR. Cell lines including MDCKII-BCRP and MDCKII-WT were used for evaluating the function and expression of BCRP. The results showed that MN (100–12.5 µM) and HK (100–12.5 µM) significantly decreased the function of BCRP by 80~12% and 67~14%, respectively. In addition, MN and HK were verified as substrates of BCRP. Furthermore, MN and HK reduced the protein expression of BCRP, and inhibited the phosphorylation of epidermal growth factor receptor (EGFR) and phosphatidylinositol 3-kinase (PI3K). In conclusion, both MN and HK decreased the function and expression of BCRP via EGFR/PI3K signaling pathway. Therefore, both compounds were promising candidates for reversing the MDR of chemotherapy.

Evodiamine Inhibits Gastric Cancer Cell Proliferation via PTEN-Mediated EGF/PI3K Signaling Pathway

Aims. In this study, the pharmacological effects and potential molecular mechanisms of evodiamine in treating gastric cancer (GC) were investigated. Methods. GC cells lines of AGS and BGC-823 were treated with evodiamine at various concentrations for different times (24, 48, and 72 h). Inhibition of the proliferation of AGS and BGC-823 cells was assessed using a CCK-8 assay. The morphology of gastric cancer cells was detected by high-content screening (HCS). The apoptosis-inducing effect of evodiamine on AGS and BGC-823 cells was detected by flow cytometric analysis. Cell migration and invasion were detected by Transwell assay. The relative mRNA and protein expression levels of PTEN-mediated EGF/PI3K signaling pathways were investigated via RT-qPCR or western blotting, respectively. Results. Evodiamine substantially inhibited AGS and BGC-823 cells proliferation in a dose- and time-dependent manner. Flow cytometric analysis revealed that evodiamine could induce apoptosis of AGS and BGC-823 cells in a dose-dependent manner. In addition, evodiamine inhibited AGS and BGC-823 cell migration and invasion. Mechanistically, the results demonstrated that evodiamine promoted the relative mRNA and protein expression of PTEN and decreased expression of EGF, EGFR, PI3K, AKT, p-AKT, and mTOR. Most importantly, evodiamine could effectively increase the mRNA and protein expression of PTEN and decrease the protein expression of EGF/PI3K pathway, indicating that evodiamine downregulated EGF/PI3K through the activation of PTEN pathway. Conclusion. Evodiamine inhibited the directional migration and invasion of GC cells by inhibiting PTEN-mediated EGF/PI3K signaling pathway. These findings revealed that evodiamine might serve as a potential candidate for the treatment or prevention of GC.

Comprehensive targeted next-generation sequencing in patients with slow-flow vascular malformations

Recent studies have shown that the PI3K signaling pathway plays an important role in the pathogenesis of slow-flow vascular malformations (SFVMs). Analysis of genetic mutations has advanced our understanding of the mechanisms involved in SFVM pathogenesis and may identify new therapeutic targets. We screened for somatic variants in a cohort of patients with SFVMs using targeted next-generation sequencing. Targeted next-generation sequencing of 29 candidate genes associated with vascular anomalies or with the PI3K signaling pathway was performed on affected tissues from patients with SFVMs. Fifty-nine patients with SFVMs (venous malformations n = 21, lymphatic malformations n = 27, lymphatic venous malformations n = 1, and Klippel–Trenaunay syndrome n = 10) were included in the study. TEK and PIK3CA were the most commonly mutated genes in the study. We detected eight TEK pathogenic variants in 10 samples (16.9%) and three PIK3CA pathogenic variants in 28 samples (47.5%). We also identified a pathogenic variant in RASA1 in one sample. In total, 38 of 59 patients (64.4%) with SFVMs harbored pathogenic variants in these three genes involved in the PI3K signaling pathway. Inhibitors of this pathway may prove useful as molecular targeted therapies for SFVMs.

Bombyxin II Regulates Glucose Absorption and Glycogen Synthesis through the PI3K Signaling Pathway in HepG2 Cells

Bombyxin, as an insulin-like insect hormone, was discovered in the silkmoth Bombyx mori. It can regulate the metabolism of trehalose and glycogen in Bombyx mori, but whether it has glucose absorption and glycogen synthesis effect on mammalian cells was not clear. BombyxinII (BbxII) and mutant BbxII (mBbxII) genes were cloned into pcDNA3.1(+) vector, respectively; then, gene vectors were transfected into 293FT cells using Lipofectamine 2000. Levels of mRNA and protein expression of BbxII and mBbxII were detected by PCR and Western blot in 293FT cells, respectively. Glucose consumption and glycogenesis were determined by glucose oxidase-peroxidase (GOD-POD) and periodic acid-Schiff (PAS) staining in HepG2 cells; the PI3K signaling pathway was inhibited with wortmannin S1952 in HepG2 cells. Result showed that BbxII and mBbxII genes were being successfully expressed in 293FT cells, respectively. The expression protein of BbxII gene is 10kd pre-bombyxinII, and yet, the expression protein of mBbxII gene is 4kd mature bombyxinII. Only the 4kd bombyxinII showed increased glucose uptake and glycogenesis in HepG2 cells, and the ability of increasing glucose uptake was equal to the human insulin (10 nM). PI3K-wortmannin S1952 inhibitor can decrease the glycogen synthesis induced by bombyxin II protein in HepG2 cells. In conclusion, mature bombyxin II may adjust glucose absorption and glycogen synthesis in HepG2 cells through the PI3K signaling pathway.

Knockdown of microRNA-126 Suppresses Non-Small-Cell Lung Cancer via Inhibiting PI3K-AKT-mTOR Pathway

Background As one of the most common cause of cancer death in the world, lung cancer causes approximate 1.6 million deaths annually. Among, NSCLC accounts approximately 85% of patients in whole lung cancer patients. As one of miRNAs, miR-126 closely involves in pathogenesis of several types of cancers including colorectal, prostate, bladder and gastric cancer, and so on. Thus, the present study aims to investigate effects of miR126 on pathogenesis of NSCLC. In the study, two lung cancer cell lines including A549 and H1650 were used. Results It was found that expression of miR126 was decreased in PBMC of NSCLC patients compared to healthy control. Expression of miR126 was decreased in cancer tissue compared to paracancerous tissues in NSCLC patients. MiR-126 KD remarkably increased expression of apoptosis genes including caspase3 and capsae9, and decreased cell viability in lung cancer cells including A549 and H1650 cells. Interesting, In Silico analysis indicated that miR-126 could target PI3K signaling pathway, which was confirmed by WB assay. KD of PI3KR2 compromised promotion of miR-126 on cell apoptosis. Similarly, it was found that KD of mTOR compromised promotion of miR-126 on cell apoptosis. Conclusions Thus, the present study confirmed that miR-126 plays an important role in apoptosis of lung cells via mTOR signaling pathway. miR-126 might be a potential therapeutic target for developing novel drugs against NSCLC.

Modeling PTEN overexpression-induced microcephaly in human brain organoids

The phosphatase and tensin homolog (PTEN) protein, encoded by the PTEN gene on chromosome 10, is a negative regulator of the phosphoinositide 3-kinase (PI3K) signaling pathway. Loss of PTEN has been linked to an array of human diseases, including neurodevelopmental disorders such as macrocephaly and autism. However, it remains unknown whether increased dosage of PTEN can lead to human disease. A recent human genetics study identifies chromosome 10 microduplication encompassing PTEN in patients with microcephaly. Here we generated a human brain organoid model of increased PTEN dosage. We showed that mild PTEN overexpression led to reduced neural precursor proliferation, premature neuronal differentiation, and the formation of significantly smaller brain organoids. PTEN overexpression resulted in decreased AKT activation, and treatment of wild-type organoids with an AKT inhibitor recapitulated the reduced brain organoid growth phenotypes. Together, our findings provide functional evidence that PTEN is a dosage-sensitive gene that regulates human neurodevelopment, and that increased PTEN dosage in brain organoids results in microcephaly-like phenotypes.

Gastroprotection against Rat Ulcers by Nephthea Sterol Derivative

Different species belonging to the genus Nephthea (Acyonaceae) are a rich resource for bioactive secondary metabolites. The literature reveals that the gastroprotective effects of marine secondary metabolites have not been comprehensively studied in vivo. Hence, the present investigation aimed to examine and determine the anti-ulcer activity of 4α,24-dimethyl-5α-cholest-8β,18-dihydroxy,22E-en-3β-ol (ST-1) isolated from samples of a Nephthea species. This in vivo study was supported by in silico molecular docking and protein–protein interaction techniques. Oral administration of ST-1 reduced rat stomach ulcers with a concurrent increase in gastric mucosa. Molecular docking calculations against the H+/K+-ATPase transporter showed a higher binding affinity of ST-1, with a docking score value of −9.9 kcal/mol and a pKi value of 59.7 nM, compared to ranitidine (a commercial proton pump inhibitor, which gave values of −6.2 kcal/mol and 27.9 µM, respectively). The combined PEA-reactome analysis results revealed promising evidence of ST-1 potency as an anti-ulcer compound through significant modulation of the gene set controlling the PI3K signaling pathway, which subsequently plays a crucial role in signaling regarding epithelialization and tissue regeneration, tissue repairing and tissue remodeling. These results indicate a probable protective role for ST-1 against ethanol-induced gastric ulcers.

FOXM1 Promotes Head and Neck Squamous Cell Carcinoma via Activation of the Linc-ROR/LMO4/AKT/PI3K Axis

Background/AimPrevious literature has implicated the sustained expression of FOXM1 in numerous human cancers, including head and neck squamous cell carcinoma (HNSCC). The current study aimed to elucidate the function and regulatory mechanism of FOXM1 in HNSCC.MethodsWestern blot and RT-qPCR methods were performed to evaluate the expression of Linc-ROR, FOXM1, and LMO4 in HNSCC tissue samples and cells. The binding between FOXM1 and Linc-ROR was analyzed using a ChIP assay. Various cellular processes including proliferation and invasion abilities were assessed following alteration of FOXM1, Linc-ROR and LMO4 expression in HNSCC cells. Xenograft mouse models were established to validate the in vitro findings.ResultsLinc-ROR and FOXM1 were highly expressed in HNSCC tissues and cells. FOXM1 operated as a potential transcription factor to bind to the promoter region of Linc-ROR. Linc-ROR and FOXM1 exhibited high expression levels in both the clinical tissue samples as well as the HNSCC cells, which could facilitate the proliferation and invasion of HNSCC cells. Linc-ROR upregulated the expression of LMO4 and promoted activation of the AKT/PI3K signaling pathway, thus stimulating the proliferation and invasion of HNSCC cells. Silencing of Linc-ROR brought about a contrasting effect relative to that seen when FOXM1 was overexpressed in HNSCC in vivo.ConclusionsOverall, FOXM1 promoted the expression of Linc-ROR and induced the activation of the LMO4-dependent AKT/PI3K signaling pathway, thus facilitating the occurrence and development of HNSCC.