Journal of Receptors and Signal Transduction最新文献

Purpose: Doxorubicin (DOX) is a common chemotherapeutic agent, with toxic side effects, and chemoresistance. Combination chemotherapy is a successful approach to overcome these limitations. Here, we investigated the effects of pioglitazone (PGZ), a PPARγ agonist, and/or DOX on the viability, cell cycle, apoptosis on THP-1 cells and normal human monocytes (NHMs).

Methods: MTT assay was used to evaluate the cytotoxicity of DOX and/or PGZ. Cell cycle progression and apoptosis induction were examined by PI or Annexin V-PI double staining, and analyzed by flow cytometry. Quantitative RT-PCR was used to evaluate the changes in the mRNA expression of cell cycle progression or apoptosis-associated genes including P27, P21, CDK2, P53, BCL2 and FasR.

Results: DOX, PGZ and DOX + PGZ exerted their cytotoxic effects in a dose- and time-dependent manner with low toxicity on NHMs. The cell growth inhibitory effects of DOX were in association with G2/M arrest, while PGZ executed S phase arrest. PGZ treatment enhanced G2/M among DOX-treated combinations with moderate elevation in the S phase. DOX, PGZ and combined treatments induced apoptosis (mostly late phase) in a dose-dependent manner. All treatments resulted in the significant overexpression of p21, p27, p53 and FasR genes and downregulation of CDK2. DOX + PGZ combined treatments exhibited the most significant changes in mRNA expression.

Conclusion: We demonstrated that the antiproliferative, cell cycle regulation and apoptosis-inducing capacity of DOX was enhanced by PGZ in THP-1 leukemia cells in a dose-dependent manner. Therefore, the combination of DOX + PGZ could be used as a novel combination to target AML.

Purpose: Long non-coding RNA (lncRNA) XIST has been shown to be involved in the immune escape of breast cancer, but it is unclear whether it is involved in the immune escape of lung cancer, so it will be discussed in this study.

Methods: XIST and miR-34a-5p expression in lung cancer tissues and cells were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The targeting relationship between miR-34a-5p and XIST/programmed cell death receptor ligand 1 (PDL1) was predicted by bioinformatics website and verified by dual-luciferase report experiment. After co-transfection with XIST specific short hairpin RNA (sh-XIST) and miR-34a-5p inhibitors, the changes in PDL1 expression, and cell biological behavior were detected by qRT-PCR, cell counting kit 8, flow cytometry, and Transwell experiments. Similarly, after co-transfection of PDL1 specific small interfering RNA (siPDL1) and miR-34a-5p inhibitors, the changes in cell biological behavior were detected again. After CD8+ T cells were co-cultured with lung cancer cells transfected with sh-XIST and miR-34a-5p inhibitors, the expression of cytokines and immunosuppressive molecules was detected by western blot and enzyme-linked immunosorbent assay (ELISA).

Results: XIST was up-regulated in lung cancer tissues, while miR-34a-5p was the opposite. XIST up-regulated the expression of PDL1 by targeting miR-34a-5p, thereby affecting the viability, apoptosis, migration, and invasion of lung cancer cells. In the co-culture system, XIST targeted miR-34a-5p to inhibit cytokines secretion and promote the expression of immunosuppressive molecules.

Conclusions: XIST/miR-34a-5p/PDL1 axis was involved in the malignant biological behavior of lung cancer cells and the immune function of CD8⁺ T cells.

The pseudoguaianolide-type sesquiterpene lactone (SL) britannin (BRT), found in different Inula species, has been characterized as a potent anticancer agent acting via modulation of the transcription factor NFkB and the Nrf2-Keap1 signaling pathway. In addition, a BRT-induced down-regulation of the immune checkpoint PD-L1 (programmed cell death ligand 1) expressed on cancer cells has been evidenced. Here we have performed a docking analysis of the direct binding of BRT to the PD-L1 protein, both in its monomeric and dimeric state. BRT appears to form stable complexes with PD-L1, with a preference for the dimeric form, binding at the interface of the two monomers. The calculated empirical energy of interaction (ΔE) value reaches -63.1 kcal/mol for the BRT-PD-L1 dimer complex, not far from the value calculated with the reference PD-L1 ligand BMS-202 (ΔE = -73.4 kcal/mol) under identical conditions. We also studied the potential PD-L1 dimer binding of 15 pseudoguaianolide sesquiterpene lactones analogues to BRT, including helenalin, gaillardin, bigelovin, coronopilin, and others. The docking analysis predicted that the SL chamissonolide (CHM) can also form equally stable complexes with PD-L1 dimer (ΔE = -64.8 kcal/mol). Preliminary compound structure-PD-L1 binding relationships have been delineated. This computational study supports the proposed interaction of BRT with PD-L1 and provides a guidance to the design of novel PD-L1 binders incorporating a SL-like tricyclic core unit.

Bipolar disorder (BD) is a severe mental illness characterized by aberrant mood changes between hypomania and mania or mixed states and depression. Metabolic changes also accompany disease progression and cause significant morbidity. Symptomatic treatment options are available, but asymptomatic patients and poor drug responders are significant problems. Based on the most common pharmacological agent that is used in the treatment, lithium and its main mechanisms of action, oxidative stress, and glycogen synthase kinase-3β (GSK-3β) signaling are extensively investigated. However, knowledge about the effects of compounds that positively affect oxidative stress and GSK-3β signaling, such as glucagon-like peptide-1 (GLP-1) mimetics, liraglutide, is still missing. Therefore, in this study, we aimed to investigate the effects of liraglutide on the ouabain-induced bipolar disease model in rats. After intracerebroventricular single dose ouabain administration, animals were treated with 100, 200, and 400 µg/kg liraglutide (s.c.) and valproic acid (200 mg/kg, i.p.) for 10 d. The locomotion and depressive states of animals were assessed by an open field, forced swimming test, and sucrose preference tests. Serum total antioxidant (TAS) and oxidant states (TOS) and glutathione, malonyl dialdehyde (MDA) levels in the brain tissue were determined. GSK-3β phosphorylation was evaluated by western blotting. Our results demonstrated that liraglutide attenuated ouabain-induced hyperlocomotion and depressive state. Additionally, liraglutide prevented oxidative stress after ouabain administration. Decreased GSK-3β phosphorylation due to the ouabain insult was alleviated by liraglutide treatment. These findings indicate that the manic and depressive-like behaviors are ameliorated by liraglutide, which exerted antioxidant action, possibly improving GSK-3β phosphorylation.

In this study, it was aimed to analyze behavioral changes of adrenergic receptors (ARs) in first three passages and osteogenic/adipogenic differentiation of mesenchymal stem cells (MSCs) derived from placenta fetal membrane (FM) and bone marrow (BM). It was also aimed to evaluate effects of receptor blockade on differentiation. We obtained first three passages of MSCs from placenta and BM samples. For cell identification, the cells were analyzed by flow cytometry using CD34, CD45 and CD3, CD105 antibodies in each passage. The effects of propranolol and phenoxybenzamine at incremental doses were analyzed by MTT. In addition, cell cultures were separately maintained with the blockers or without after second passage. After each passage and differentiation, α1A, α1B, α2A, α2B, β1, β2, β3 AR-mRNA expressions analyzed by RT-qPCR technique. BMP6 and PPARG mRNA expressions only after differentiation and passage 3 were analyzed. A microscopic examination was also performed. Our results showed that AR expression behaviors were different in MSCs obtained from different tissue sources. In particular, α_1A-AR and α_2A-AR were expressed with considerably high coefficients in differentiation under blocker effect in BM-derived MSCs. No such coefficients were observed in any group of placental MSCs. In addition, it was found that the blockers stimulated adipogenesis in BM-derived MSCs during osteogenic differentiation. MSCs exhibit protein expressions that vary according to source of tissue and differentiation. Given that MSCs from different sources are used for repair and modulation, our study makes implications of this variable expression intriguing in the clinical practice.

Increasing diabetic population is one of the major health concerns all over the world. Inhibition of α-glucosidase is a clinically proved and attractive strategy to manage diabetes. In this study, robust and reliable QSAR models to predict α-glucosidase inhibitory potential of xanthone derivatives are developed by the Monte Carlo technique. The chemical structures are represented by SMILES notation without any 3D-optimization. The significance of the index of ideality correlation (IIC) with applicability domain (AD) is also studied in depth. The models developed using CORAL software by considering IIC criteria are found to be statistically more significant and robust than simple balance of correlation. The QSAR models are validated by both internal and external validation methods. The promoters of increase and decrease of activity are also extracted and interpreted in detail. The interpretation of developed models explains the role of different structural attributes in predicting the pIC₅₀ of xanthone derivatives as α-glucosidase inhibitors. Based on the results of model interpretation, modifications are done on some xanthone derivatives and 15 new molecules are designed. The α-glucosidase inhibitory activity of novel molecules is further supported by docking studies.

QSAR modeling was performed on 39 quinolone-triazole derivatives against gram-positive Staphylococcus aureus and gram-negative Pseudomonas aeruginosa bacteria. The molecular structures were optimized using the DFT/B3LYP method and 6-31 G basis set. Molecular descriptors were extracted using quantum mechanical calculations. The hierarchical cluster analysis was performed for a rational subset division. The initial dataset was divided into calibration and validation sets, and modeling was done by stepwise MLR method for each of the two bacteria. Internal and external validation methods confirmed the robustness and predictability of the obtained models. According to the obtained model for S. aureus (R² = 0.889, R²_ext = 0.938, Q²_LOO = 0.853), the four descriptors- partial atomic charges for the N1 atom in triazole and C7 of the quinolone nucleus, 4-carbonyl bond length, and ¹³C-NMR chemical shift of 3-carboxylic acid- were found to be the descriptors controlling the activity. According to the obtained model for P. aeruginosa (R² = 0.957, R²_ext = 0.923, Q²_LOO = 0.909), the O atom's partial charge in carbonyl, LUMO-HOMO energy gap, and logP were found to be the descriptors having the highest correlation with the antibacterial activity. Finally, some new compounds with higher activities were designed and proposed.

Hyperuricemia always develops into hyperuricemic nephropathy (HN). The role of microRNA (miR) in HN is less studied. We aimed to discuss the role of miR-199a in HN. The expression of miR-199a and PPARγ in renal tissues of HN rats was detected. The targeting relation between miR-199a and PPARγ was verified. The contents of SCr, UA, BUN, and mALB, renal injury-relevant biomarkers were detected, and the pathological changes of renal tissue and renal interstitial fibrosis were observed by histological staining. After miR-199a and PPARγ knockdown, the contents of SCr, BUN, and mALB and renal interstitial fibrosis were estimated. Collectively, overexpression of miR-199a aggravated the renal injury in HN rats. By contrast, inhibition of miR-199a weakened renal injury, as evidenced by decreased contents of SCr, UA, BUN, and mALB, and mitigated renal interstitial fibrosis. miR-199a targeted PPARγ. Silencing of PPARγ upregulated the levels of downstream genes of β-catenin and the contents of SCr, UA, BUN, and mALB and deteriorated renal interstitial fibrosis. Moreover, the silencing of PPARγ blocked the alleviative effects of miR-199a inhibitor on the renal injury. Overall, miR-199a targets PPARγ and activates the β-catenin pathway, thus aggravating HN, which might provide a future target for the treatment of HN.

Recent studies have shown that many long noncoding RNAs (lncRNAs) are abnormally expressed in ovarian cancer and involved in the pathological progress of ovarian cancer. In the present study, we aimed to investigate the role of lncRNA LINC00858 and the potential mechanism in ovarian cancer. The qRT-PCR was used to measure the expression levels of LINC00858 and miR-134-5p in ovarian cancer tissue specimens and cell lines. Loss-of-function assays were performed to investigate the role of LINC00858 in ovarian cancer. MTT assay was carried out to measure cell proliferation. Transwell assays were performed to determine cell migration and invasion. Biological information analysis and luciferase report gene assay were used to verify potential downstream genes of LINC00858. The xenograft mouse model was established to analyze tumor growth in vivo. Our results showed that LINC00858 was highly expressed in human ovarian cancer tissues and cell lines. Knockdown of LINC00858 inhibited cell proliferation, migration and invasion of SKOV3 cells, and suppressed tumor growth in mouse xenograft models. Mechanistic studies revealed that LINC00858 acted as a sponge of miR-134-5p and then regulated TRIM44 expression in SKOV3 cells. Furthermore, rescue experiments illustrated that inhibition of miR-134-5p restored the inhibitory effects of LINC00858 knockdown on cell proliferation, migration and invasion. TRIM44 overexpression could counteract the inhibitory effects of miR-134-5p mimics on ovarian cancer cells. In conclusion, these findings demonstrated that LINC00858 exerted oncogenic role in ovarian cancer, which was mediated by miR-134-5p/TRIM44 axis. Thus, LINC00858 might be a therapeutic target for the treatment of ovarian cancer.

Purpose: Previous studies have proved that zingerone was a therapeutic agent for many tumors. Metadherin (MTDH) acts as an oncogene and is involved in tumorigenesis. The purpose of this study was to explore the underlying mechanism of zingerone that regulates MTDH to affect hepatocellular carcinoma (HCC) progression.

Methods: CCK-8 assay was performed to detect HCC cell proliferation. The invasion and migration abilities of HCC cells were evaluated using Transwell assay. The mRNA and protein levels in cells and tissues were measured using qRT-PCR and Western blot assays. Moreover, we established the HCC xenografts nude mice to evaluate the effect of zingerone on tumor growth.

Results: We found that zingerone treatment significantly inhibited HCC cell malignant phenotype and tumor growth. Moreover, MTDH was highly expressed in HCC tissues and cell lines and was positively associated with poor overall survival of patients with HCC. Knockdown of MTDH notably suppressed the proliferation, invasion, and migration capacities of HCC cells. Mechanistically, inhibition of MTDH by zingerone impeded the malignant biological behavior of HCC cells by inactivating the PI3K/Akt pathway.

Conclusion: These results suggested that zingerone served as an effective therapeutic agent in HCC via blocking the MTDH-mediated PI3K/Akt pathway.