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Purpose: Urinary bladder urothelial carcinoma (UBUC) is a common malignant disease, and its high recurrence rates impose a heavy clinical burden. The objective of this study was to identify signaling pathways downstream of epithelial membrane protein 2 (EMP2), which induces cytostasis and apoptosis in UBUC., Methods: A series of in vitro and in vivo assays using different UBUC-derived cell lines and mouse xenograft models were performed, respectively. In addition, primary UBUC specimens were evaluated by immunohistochemistry., Results: Exogenous expression of EMP2 in J82 UBUC cells significantly decreased DNA replication and altered the expression levels of several TGFβ signaling-related proteins. EMP2 knockdown in BFTC905 UBUC cells resulted in opposite effects. EMP2-dysregulated cell cycle progression was found to be mediated by the TGFβ/TGFBR1/SP1 family member SMAD. EMP2 or purinergic receptor P2X7 (P2RX7) gene expression upregulation induced apoptosis via both intrinsic and extrinsic pathways. In 242 UBUC patient samples, P2RX7 protein levels were found to be significantly and positively correlated with EMP2 protein levels. Low P2RX7 levels conferred poor disease-specific and metastasis-free survival rates, and significantly decreased apoptotic cell rates. EMP2 was found to physically interact with P2RX7. In the presence of a P2RX7 agonist, BzATP, overexpression of both EMP2 and P2RX7 significantly increased apoptotic cell rates compared to overexpression of EMP2 or P2RX7 alone., Conclusions: EMP2 induces cytostasis via the TGFβ/SMAD/SP1 axis and recruits P2RX7 to enhance apoptosis in UBUC. Our data provide new insights that may be employed for the design of UBUC targeting therapies., (© 2021. Springer Nature Switzerland AG.)

The objective was to investigate the upstream mechanisms of apoptosis which were triggered by a novel antimicrotubule drug, ABT-751, in a tumor protein p53 ( TP53)-deficient hepatocellular carcinoma-derived Hep-3B cells. A series of in vitro assays indicated that ABT-751 caused the disruption of the mitotic spindle structure, collapse of mitochondrial membrane potential, generation of reactive oxygen species, DNA damage, G 2 /M cell cycle arrest, inhibition of anchorage-independent cell growth and apoptosis in Hep-3B cells accompanied by alteration of the expression levels of several DNA damage checkpoint proteins and cell cycle regulators. Subsequently, ABT-751 triggered apoptosis along with markedly upregulated several proapoptotic proteins involving in extrinsic, intrinsic, and caspase-mediated apoptotic pathways. A pan-caspase inhibitor suppressed ABT-751-induced apoptosis. ABT-751 also induced autophagy soon after the occurrence of apoptosis through the suppression of AKT serine/threonine kinase/mechanistic target of rapamycin signaling pathway. Exogenous expression of the TP53 gene significantly incurred both apoptosis and autophagy in Hep-3B cells. Pharmacological inhibition of autophagosome (early autophagy) but not autolysosome (late autophagy) enhanced ABT-751-induced apoptosis in TP53-deficient Hep-3B cells. Our study provided a new strategy to augment ABT-751-induced apoptosis in TP53-deficient cells., (© 2018 Wiley Periodicals, Inc.)

Thirty Cryptolepine and Aromathecin based mimics were designed and synthesized. Their cytotoxicity was evaluated in four human cancer cell lines (HepG-2, T24, NCI-H460 and MGC-803) and one normal human cell line (HL-7702). Most compounds exhibited potent anticancer activity with IC 50 values from 0.31 to 11.97 μM. 8-Fluoro-10-(N-3-dimethylaminopropyl)amino-11H-indeno[1,2-b]quinoline (5b) was identified as the most promising candidate in view of its anticancer activity. Molecular mechanism studies suggested that 5b not only could strongly bind to G-quadruplex, but intercalate into supercoil DNA and resulted in significant DNA double-strand break as well. Furthermore, 5b caused cell cycle arrest at S/G2 phase and induced apoptosis. After treatment with 5b, pro-apoptotic proteins Bak, Bax and Bim were up-regulated, anti-apoptotic proteins Bcl-2 and Bcl-xL were down-regulated, and the effector caspase-3/9 was activated to initiate apoptosis. The anticancer activity of 5b was finally validated in a MGC-803 xenograft tumor model with tumor growth inhibition (TGI) up to 53.2%, while displaying no obvious toxicity. Taken together, these results suggest that 5b may be a potential candidate of cytotoxic antineoplastic drugs for cancer therapy., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Aim: To study the effect of resveratrol (RES) on the apoptosis of lymphocytes in allograft in a rat liver transplantation model., Methods: Male Sprague-Dawley (SD) rats were selected as donors and male Wistar rats as recipients for a rejection model. The recipients were divided into four groups after orthotopic liver transplantation (OLTx). In the RES A, B, and C groups, RES was given intraperitoneally once a day (25, 50, and 100 mgkg(-1), respectively) after OLTx, whereas in the control group vehicle buffer was given intraperitoneally once a day. The survival period, lymphocytes apoptosis, expressions of Bcl-2/Bax proteins in lymphocytes, and histopathological findings were then compared among these groups., Results: The mean survival period after OLTx in RES C group was significantly longer than that in control group (P < 0.05). On the seventh post-transplant day, the apoptosis index (AI) of lymphocytes in portal area and the positive rate of Bax protein in lymphocytes in RES C group were significantly increased in comparison with those in control group (both P < 0.05), whereas there is no obvious difference in the expression of Bcl-2 protein in lymphocytes between the control group and various drug groups (all P < 0.05), and a histological examination revealed apparent difference in the severity of rejection between the RES C group and control group (P < 0.05)., Conclusion: RES has an immunosuppressive effect on lymphocytes under allograft rejection in rat. Inducing apoptosis of lymphocytes and upregulating the ratio of Bax/bcl-2 proteins in lymphocytes in allograft liver may be part of the mechanisms.

Although in vivo and in vitro zearalenone (ZEN) exposure impaired oocyte quality, the mechanisms by which ZEN damages oocytes and the lowest observed effect level remain unclear. Furthermore, although it is known that premature chromatin condensation may occur in oocytes under proapoptotic conditions, whether ZEN exposure compromises oocyte competence by impairing gene transcription by causing premature chromatin condensation remains to be investigated. This study tested the toxic concentrations of in vivo ZEN exposure that impair oocyte preimplantation developmental potential (PIDP) and the hypothesis that ZEN exposure compromises oocyte competence by increasing oxidative stress and changing chromatin configuration and the transcription of related genes. We found that in vivo treatment of mice (Kunming strain, 8 weeks after birth) with 0.5–1 mg kg−1 ZEN daily for 5 days, impaired the PIDP of mouse oocytes, increased oxidative stress, disturbed spindle assembly and chromosome segregation, caused premature chromatin condensation, impaired global gene transcription and disturbed the expression of genes related to oocyte competence, spindle assembly, redox potential and apoptosis. In conclusion, ZEN dose-dependently compromised the competence of mouse oocytes by causing oxidative stress and impairing chromatin configuration and gene transcription. Because zearalenone (ZEN) can enter the food chain and cause health problems, studies of its toxic effects on oocytes are of great importance for healthy reproduction in both humans and animals. This study demonstrates that ZEN dose-dependently compromises the competence of mouse oocytes by causing oxidative stress and impairing chromatin configuration and gene transcription. These data will contribute to our understanding of the mechanisms by which ZEN and other similar toxins impair oocyte quality, and thus female reproduction. [ABSTRACT FROM AUTHOR]

Twenty-seven 3-(benzo[d]thiazol-2-yl)-4-aminoquinoline derivatives have been designed and synthesized as topoisomerase I inhibitors. The in vitro anti-proliferation evaluation against four human cancer cell lines (MGC-803, HepG-2, T24, and NCI-H460) and one normal cell line (HL-7702) indicated that most of them exhibited potent cytotoxicity. Among them, 5a was identified as the most promising candidate with a low IC50 value of about 2.20 ± 0.14 and was selected for further exploration. Spectroscopic analyses and agarose-gel electrophoresis assays indicated that 5a could interact with DNA and strongly inhibit topoisomerase I (Topo I). Further screening of the Topo I activity of compounds 5b, 5c, 5e, 5f, 5h, 5i, 5j, 5l, and 5n suggested that some of the compounds might exert quite a different cytotoxicity profile to that of 5a. Molecular modeling studies confirmed that 5a adopts a unique mode to interact with DNA and Topo I. Other molecular mechanistic studies suggested that the treatment of MGC-803 cells with 5a induces S phase arrest, up-regulates the pro-apoptotic protein, down-regulates the anti-apoptotic protein, activates caspase-3, and subsequently induces mitochondrial dysfunction so as to induce cell apoptosis. The in vivo efficiency of 5a was also evaluated on MGC-803 xenograft nude mice and the relative tumor growth inhibition was 42.4% at 12 mg kg−1 without an obvious loss in the body weight. [ABSTRACT FROM AUTHOR]

Diabetic gastroparesis (DGP), also known as delayed gastric emptying, is a common complication of diabetes mellitus. There are numerous clinical symptoms associated with DGP, as well as high treatment costs and markedly reduced patient quality of life. However, the pathogenesis of DGP is not clear, thus effective treatment methods are yet to be established. In the present study, a DGP rat model was established in Sprague-Dawley rats by the intraperitoneal injection of streptozotocin (STZ). DGP model rats were treated with different doses of atractylenolide-1 to detect alterations in gastrointestinal function, including gastroparesis, gastric emptying, gastric motility, gastric peristalsis and gastric blood flow. Compared with the DGP group, atractylenolide-1 treatment significantly reduced glycaemia and the level of glycated hemoglobin, as well as restoring gastrointestinal function. Gastroparesis, gastric emptying, gastric motility, gastric peristalsis and gastric blood flow were significantly impaired in the STZ-induced group compared with the vehicle control group. Moreover, the STZ-induced group displayed downregulated expression levels of the DGP indicator KIT proto-oncogene, receptor tyrosine kinase (c-kit), as investigated by immunohistochemistry, and stem cell factor (SCF) protein, as assessed using ELISA, significantly enhanced rat interstitial cells of Cajal (ICC) apoptosis, and significantly altered levels of oxidative stress-related markers (malondialdehyde and superoxide dismutase) in the serum and gastric tissues compared with the vehicle control group. By contrast, treatment with atractylenolide-1 significantly counteracted the effects of DGP on peristalsis, inhibited apoptosis and suppressed oxidative stress by regulating the expression of heme oxygenase 1 in STZ-induced DGP model rats. Further research indicated that atractylenolide-1 regulated oxidative stress reactions and improved gastric function by activating the SCF/c-kit signaling pathway. Collectively, the results of the present study suggested that atractylenolide-1 promoted ICC survival and preserved the structure of the gastric tissue network in a DGP rat model via the SCF/c-kit signaling pathway, providing novel insights for the treatment of DGP. [ABSTRACT FROM AUTHOR]

The mutant p53 proteins and their corresponding cellular response can be manipulated by novel quinazolinone derivatives 4 – 8 ( a – i ) in p53 mutant cancer cells. Of the two most potent compounds, 4a exhibited promising broad-spectrum anti-cancer effects, whereas 6c showed selective and exclusive inhibition activity in p53 mutant cancer cell lines but low toxicity to wild-type p53 cancer cell A375 and normal lung fibroblast WI-38 cells. Furthermore, 6c exhibited a more sophisticated mechanism for cell-destructive response by causing S/G2 phase arrest effect and cell size reduction. Compared with the cellular response of 6b and genetic background of cell lines studied, p53 mutation was found to be the key factor and main target for 6c evoked cell-destructive response. Molecular mechanism studies indicated that p53 phosphorylation and acetylation dual-targeting inhibitor 6c exerted anti-cancer activities with a special mechanism in evoking cell apoptosis by arresting mutant p53 function to trigger the deregulation of Cdk2 caused Bim-mediated apoptosis. To the best of our knowledge, 6c is the first quinazolinone derivative to dictate mutant p53 function for apoptotic cell death. [ABSTRACT FROM AUTHOR]

[Display omitted] • New PI3K-Akt-mTOR inhibitor was in silico designed. • New quinoxaline-based dual inhibitor was identified. • Activate the P53 and induce the generation of ROS. • Display antitumor efficacy in vivo with low toxicity. Thirty-eight new 3-arylaminoquinoxaline-2-carboxamide derivatives were in silico designed, synthesized and their cytotoxicity against five human cancer cell lines and one normal cells WI-38 were evaluated. Molecular mechanism studies indicated that N -(3-Aminopropyl)-3-(4-chlorophenyl) amino-quinoxaline-2-carboxamide (6be), the compound with the most potent anti-proliferation can inhibit the PI3K-Akt-mTOR pathway via down regulating the levels of PI3K, Akt, p-Akt, p-mTOR and simultaneously inhibit the phosphorylation of Thr308 and Ser473 residues in Akt kinase to servers as a dual inhibitor. Further investigation revealed that 6be activate the P53 signal pathway, modulated the downstream target gene of Akt kinase such p21, p27, Bax and Bcl-2, caused the fluctuation of intracellular ROS, Ca2+ and mitochondrial membrane potential to induce cell cycle arrest and apoptosis in MGC-803 cells. 6be also display moderate anti-tumor activity in vivo while displaying no obvious adverse signs during the drug administration. The results suggest that 3-arylaminoquinoxaline-2-carboxamide derivatives might server as new scaffold for development of PI3K-Akt-mTOR inhibitor. [ABSTRACT FROM AUTHOR]