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Hippocampal neurons maintain the ability of proliferation throughout life to support neurogenesis. Deoxynivalenol (DON) is a mycotoxin that exhibits brain toxicity, yet whether and how DON affects hippocampal neurogenesis remains unknown. Here, we use mouse hippocampal neuron cells (HT-22) as a model to illustrate the effects of DON on neuron proliferation and to explore underlying mechanisms. DON exposure significantly inhibits the proliferation of HT-22 cells, which is associated with an up-regulation of cell cycle inhibitor p21 at both mRNA and protein levels. Global and site-specific m 6 A methylation levels on the 3'UTR of p21 mRNA are significantly increased in response to DON treatment, whereas inhibition of m 6 A hypermethylation significantly alleviates DON-induced cell cycle arrest. Further mechanistic studies indicate that the m 6 A readers YTHDF1 and IGF2BP1 are responsible for m 6 A-mediated increase in p21 mRNA stability. Meanwhile, 3'UTR of E3 ubiquitin ligase TRIM21 mRNA is also m 6 A hypermethylated, and another m 6 A reader YTHDF2 binds to the m 6 A sites, leading to decreased TRIM21 mRNA stability. Consequently, TRIM21 suppression impairs ubiquitin-mediated p21 protein degradation. Taken together, m 6 A-mediated upregulation of p21, at both post-transcriptional and post-translational levels, contributes to DON-induced inhibition of hippocampal neuron proliferation. These results may provide new insights for epigenetic therapy of neurodegenerative diseases., (© 2024. The Author(s).)

Anaplastic thyroid cancer (ATC) represents the type with the worst prognosis among thyroid cancers. In ATC with a highly invasive phenotype, selective targeting of TERT with BIBR1532 may be a goal-driven approach to preserving healthy tissues. In present study, it was aimed to investigate the effects of treatment of SW1736 cells with BIBR1532 on apoptosis, cell cycle progression, and migration. The apoptotic effect of BIBR1532 on SW1736 cells was examined using the Annexin V method, the cytostatic effect using cell cycle test, migration properties using wound healing assay. Gene expression differences were determined by real-time qRT-PCR and differences in protein level by ELISA test. BIBR1532-treated SW1736 cells had 3.1-fold increase in apoptosis compared to their untreated counterpart. There was 58.1% arrest in the G 0 /G 1 phase and 27.6% arrest in the S phase of the cell cycle in untreated group, treatment with BIBR1532 increased cell population in G 0 /G 1 phase to 80.9% and decreased in S phase to 7.1%. Treatment with the TERT inhibitor resulted in a 50.8% decrease in cell migration compared to the untreated group. After BIBR1532 treatment of SW1736 cells, upregulation of BAD, BAX, CASP8, CYCS, TNFSF10, CDKN2A genes, and downregulation of BCL2L11, XIAP, CCND2 genes were detected. BIBR1532 treatment resulted in an increase in BAX and p16 proteins, and a decrease in concentration of BCL-2 protein compared to untreated group. Targeting TERT with BIBR1532 as a mono drug or using of BIBR1532 at "priming stage" prior to chemotherapy treatment in ATC may present a novel and promising treatment strategy., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Chronic myeloid leukemia (CML) is a cancer type of the white blood cells and because of BCR-ABL translocation it results in increased tyrosine kinase activity. For this purpose, dasatinib is the second-generation tyrosine kinase inhibitor that is used for inhibition of BCR-ABL. Effectively and safetly, dasatinib has been used for imatinib-intolerant/resistant CML patients. Protein phosphatase 2A (PP2A) is the major serine/threonine phosphatase ensuring cellular homeostasis in cells and is associated with many cancer types including leukemias. In this study, we aimed to investigate the effects of dasatinib and okadaic acid (OA), either alone or in combination, on apoptosis and cell cycle arrest and dasatinib effect on enzyme activity and protein-level changes of PP2A in K562 cell line. The cytotoxic effects of dasatinib were evaluated by WST-1 analysis. Apoptosis was determined by Annexin V and Apo-Direct assays by flow cytometry. Cell cycle arrest analysis was performed for the investigation of the cytostatic effect. We also used OA as a PP2A inhibitor to assess apoptosis and cell cycle arrest changes in case of reducing the level of PP2A. PP2A enyzme activity and protein levels of PP2A were examined by serine/threonine phosphatase assay and Western blot analysis, respectively. Apoptosis was increased with dasatinib and OA combination. Cell cycle arrest was determined especially after OA treatment. The enzyme activity was decreased depending on time after dasatinib application. PP2A regulatory and catalytic subunit protein levels were decreased compared to control. Targeting the PP2A by dasatinib and OA has potential for CML treatment., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The aggressive, invasive and treatment resistant nature of glioblastoma makes it one of the most lethal cancers in humans. Total surgical resection is difficult, and a combination of radiation and chemotherapy is used to treat the remaining invasive cells beyond the tumour border by inducing DNA damage and activating cell death pathways in glioblastoma cells. Unfortunately, recurrence is common and a major hurdle in treatment, often met with a more aggressive and treatment resistant tumour. A mechanism of resistance is the response of DNA repair pathways upon treatment-induced DNA damage, which enact cell-cycle arrest and repair of DNA damage that would otherwise cause cell death in tumour cells., Conclusions: In this review, we discuss the significance of DNA repair mechanisms in tumour formation, aggression and treatment resistance. We identify an underlying trend in the literature, wherein alterations in DNA repair pathways facilitate glioma progression, while established high-grade gliomas benefit from constitutively active DNA repair pathways in the repair of treatment-induced DNA damage. We also consider the clinical feasibility of inhibiting DNA repair in glioblastoma and current strategies of using DNA repair inhibitors as agents in combination with chemotherapy, radiation or immunotherapy. Finally, the importance of blood-brain barrier penetrance when designing novel small-molecule inhibitors is discussed., (© 2021. Crown.)

The Cytolethal Distending Toxin (CDT) is a bacterial genotoxin produced by pathogenic bacteria causing major foodborne diseases worldwide. CDT activates the DNA Damage Response and modulates the host immune response, but the precise relationship between these outcomes has not been addressed so far. Here, we show that chronic exposure to CDT in HeLa cells or mouse embryonic fibroblasts promotes a strong type I interferon (IFN) response that depends on the cytoplasmic DNA sensor cyclic guanosine monophosphate (GMP)-adenosine monophosphate (AMP) synthase (cGAS) through the recognition of micronuclei. Indeed, despite active cell cycle checkpoints and in contrast to other DNA damaging agents, cells exposed to CDT reach mitosis where they accumulate massive DNA damage, resulting in chromosome fragmentation and micronucleus formation in daughter cells. These mitotic phenotypes are observed with CDT from various origins and in cancer or normal cell lines. Finally, we show that CDT exposure in immortalized normal colonic epithelial cells is associated to cGAS protein loss and low type I IFN response, implying that CDT immunomodulatory function may vary depending on tissue and cell type. Thus, our results establish a direct link between CDT-induced DNA damage, genetic instability and the cellular immune response that may be relevant in the context of natural infection associated to chronic inflammation or carcinogenesis., (© 2021. The Author(s).)

Introduction Differentiation therapy is a promising strategy for cancer treatment. The translationally controlled tumor protein (TCTP) is an encouraging target in this context. By now, this field of research is still at its infancy, which motivated us to perform a large-scale screening for the identification of novel ligands of TCTP. We studied the binding mode and the effect of TCTP blockade on the cell cycle in different cancer cell lines. Methods Based on the ZINC-database, we performed virtual screening of 2,556,750 compounds to analyze the binding of small molecules to TCTP. The in silico results were confirmed by microscale thermophoresis. The effect of the new ligand molecules was investigated on cancer cell survival, flow cytometric cell cycle analysis and protein expression by Western blotting and co-immunoprecipitation in MOLT-4, MDA-MB-231, SK-OV-3 and MCF-7 cells. Results Large-scale virtual screening by PyRx combined with molecular docking by AutoDock4 revealed five candidate compounds. By microscale thermophoresis, ZINC10157406 (6-(4-fluorophenyl)-2-[(8-methoxy-4-methyl-2-quinazolinyl)amino]-4(3H)-pyrimidinone) was identified as TCTP ligand with a K D of 0.87 ± 0.38. ZINC10157406 revealed growth inhibitory effects and caused G0/G1 cell cycle arrest in MOLT-4, SK-OV-3 and MCF-7 cells. ZINC10157406 (2 × IC50) downregulated TCTP expression by 86.70 ± 0.44% and upregulated p53 expression by 177.60 ± 12.46%. We validated ZINC10157406 binding to the p53 interaction site of TCTP and replacing p53 by co-immunoprecipitation. Discussion ZINC10157406 was identified as potent ligand of TCTP by in silico and in vitro methods. The compound bound to TCTP with a considerably higher affinity compared to artesunate as known TCTP inhibitor. We were able to demonstrate the effect of TCTP blockade at the p53 binding site, i.e. expression of TCTP decreased, whereas p53 expression increased. This effect was accompanied by a dose-dependent decrease of CDK2, CDK4, CDK, cyclin D1 and cyclin D3 causing a G0/G1 cell cycle arrest in MOLT-4, SK-OV-3 and MCF-7 cells. Our findings are supposed to stimulate further research on TCTP-specific small molecules for differentiation therapy in oncology., (© 2021. The Author(s).)

Colorectal cancer (CRC) is the second most common gastrointestinal cancer globally. Prevention of tumor cell proliferation and metastasis is vital for prolonging patient survival. Polyphenols provide a wide range of health benefits and prevention from cancer. In the gut, urolithins are the major metabolites of polyphenols. The objective of our study was to elucidate the molecular mechanism of the anticancer effect of urolithin A (UA) on colorectal cancer cells. UA was found to inhibit the cell proliferation of CRC cell lines in a dose-dependent and time-dependent manner in HT29, SW480, and SW620 cells. Exposure to UA resulted in cell cycle arrest in a dose-dependent manner along with alteration in the expression of cell cycle-related protein. Treatment of CRC cell lines with UA resulted in the induction of apoptosis. Treatment of HT29, SW480, and SW620 with UA resulted in increased expression of the pro-apoptotic proteins, p53 and p21. Similarly, UA treatment inhibited the anti-apoptotic protein expression of Bcl-2. Moreover, exposure of UA induced cytochrome c release and caspase activation. Furthermore, UA was found to generate reactive oxygen species (ROS) production in CRC cells. These findings indicate that UA possesses anticancer potential and may be used therapeutically for the treatment of CRC.

Cisplatin-based therapy is a widely used chemotherapeutic regimen for non-small cell lung cancer (NSCLC); however, drug resistance limits its efficacy. Acetyl-11-keto-β-boswellic acid (AKBA), a bioactive compound from frankincense, has been shown to exert anti-cancer effects. The aim of this study is to explore the potential of AKBA in combination with cisplatin as a new regimen for NSCLC. CCK8 assay and clone formation assay were used to determine the effects of AKBA in combination with cisplatin on cell viability of NSCLC cell lines. A three-dimensional spherification assay was used to simulate in vivo tumor formation. Flow cytometry was performed to examine cell cycle distribution and the percentages of apoptotic cells. The associated proteins and mRNA of cell cycle, apoptosis, and autophagy were measured by western blotting and real-time fluorescence quantitative PCR. Immunofluorescence assay was used to test apoptotic nuclei and autolysosome. Small interfering RNA experiments were used to silence the expression of p21. Combination treatment of AKBA and cisplatin inhibited cell viability, clone formation, and three-dimensional spherification, enhanced G 0 /G 1 phase arrest, increased the percentages of apoptotic cells, and decreased the ratio of positive autolysosomes, compared with cisplatin alone. AKBA in combination with cisplatin suppressed the protein expressions of cyclin A2, cyclin E1, p-cdc2, CDK4, Bcl-xl, Atg5, and LC3A/B, and upregulated p27 and p21 mRNA levels in A549 cells. Downregulation of p21 decreased G 0 /G 1 phase arrest and the percentages of apoptotic cells, and promoted autophagy in NSCLC A549 cells. Our study demonstrates that AKBA enhances the cisplatin sensitivity of NSCLC cells and that the mechanisms involve G 0 /G 1 phase arrest, apoptosis induction, and autophagy suppression via targeting p21-dependent signaling pathway.

Lactoferrin has gained extensive attention due to its ample biological properties. In this study, recombinant human lactoferrin carrying humanized glycosylation (rhLf-h-glycan) expressed in the yeast Pichia pastoris SuperMan5, which is genetically glycoengineered to efficiently produce functional humanized glycoproteins inclosing (Man) 5 (GlcNAc) 2 Asn-linked glycans, was analyzed, inspecting its potential toxicity against cancer cells. The live-cell differential nuclear staining assay was used to quantify the rhLf-h-glycan cytotoxicity, which was examined in four human cell lines: acute lymphoblastic leukemia (ALL) CCRF-CEM, T-cell lymphoblastic lymphoma SUP-T1, cervical adenocarcinoma HeLa, and as control, non-cancerous Hs27 cells. The defined CC 50 values of rhLf-h-glycan in CCRF-CEM, SUP-T1, HeLa, and Hs27 cells were 144.45 ± 4.44, 548.47 ± 64.41, 350 ± 14.82, and 3359.07 ± 164 µg/mL, respectively. The rhLf-h-glycan exhibited a favorable selective cytotoxicity index (SCI), preferentially killing cancer cells: 23.25 for CCRF-CEM, 9.59 for HeLa, and 6.12 for SUP-T1, as compared with Hs27 cells. Also, rhLf-h-glycan showed significant antiproliferative activity (P < 0.0001) at 24, 48, and 72 h of incubation on CCRF-CEM cells. Additionally, it was observed via fluorescent staining and confocal microscopy that rhLf-h-glycan elicited apoptosis-associated morphological changes, such as blebbing, nuclear fragmentation, chromatin condensation, and apoptotic bodies in ALL cells. Furthermore, rhLf-h-glycan-treated HeLa cells revealed shrinkage of the microfilament structures, generating a speckled/punctuated pattern and also caused PARP-1 cleavage, a hallmark of apoptosis. Moreover, in ALL cells, rhLf-h-glycan altered cell cycle progression inducing the G2/M phase arrest, and caused apoptotic DNA fragmentation. Overall, our findings revealed that rhLf-h-glycan has potential as an anticancer agent and therefore deserves further in vivo evaluation.

Hormesis describes a biphasic dose-response relationship generally characterized by a low-dose excitement and a high-dose inhibition. This phenomenon has been observed in the regulation of cell, organ, and organismic level. However, hormesis has not reported in oocytes. In this study, we observed, for the first time, hormetic responses of PIPP levels in oocytes by inhibitor of Akt1 or PKCδ. The expression of PIPP was detected by qPCR, immunofluorescent (IF), and Western Blot (WB). To observe the changes of PIPP levels, we used the inhibitors against pAkt1 (Ser473) or PKCδ, SH-6 or sotrastaurin with low and/or high-dose, treated GV oocytes and cultured for 4 h, respectively. The results showed that PIPP expression was significantly enhanced when oocytes were treated with SH-6 or sotrastaurin 10 μM, but decreased with SH-6 or sotrastaurin 100 μM. We also examined the changes of PIPP levels when GV oocytes were treated with exogenous PtdIns(3,4,5)P 3 or LY294002 for 4 h. Our results showed that PIPP level was enhanced much higher under the treatment of 0.1 μM PtdIns(3,4,5)P 3 than that of 1 μM PtdIns(3,4,5)P 3 , which is consistent with the changes of PIPP when oocytes were treated with inhibitors of pAkt1 (Ser473) or PKCδ. In addition, with PIPP siRNA, we detected that down-regulated PIPP may affect distributions of Akt, Cdc25, and pCdc2 (Tyr15). Taken together, these results show that the relationships between PIPP and Akt may follow the principle of hormesis and play a key role during release of diplotene arrest in mouse oocytes.

Two novel chemotherapeutic chalcones were synthesized and their structures were confirmed by different spectral tools. Theoretical studies such as molecular modeling were done to detect the mechanism of action of these compounds. In vitro cytotoxicity showed a strong effect against all tested cell lines (MCF7, A459, HepG2, and HCT116), and low toxic effect against normal human melanocytes (HFB4). The lung carcinoma cell line was chosen for further molecular studies. Real-time PCR demonstrated that the two compounds upregulated gene expression of (BAX, p53, casp-3, casp-8, casp-9) genes and decreased the expression of anti-apoptotic genes bcl2, CDK4, and MMP1. Flow-cytometry indicated that cell cycle arrest of A459 was induced at the G2/M phase and the apoptotic percentage increased significantly compared to the control sample. Cytochrome c oxidase and VEGF enzyme activity were detected by ELISA assay. SEM tool was used to follow the morphological changes that occurred on the cell surface, cell granulation, and average roughness of the cell surface. The change in the number and morphology of mitochondria, cell shrinkage, increase in the number of cytoplasmic organelles, membrane blebbing, chromatin condensation, and apoptotic bodies were observed using TEM. The obtained data suggested that new chalcones exerted their pathways on lung carcinoma through induction of two pathways of apoptosis. Graphical abstract Novel chalcones were prepared and confirmed by different spectral tools. Docking simulations were done to detect the mechanism of action. In vitro cytotoxicity indicated a strong effect against different cancer cell lines and low toxic effects against normal human melanocytes (HFB4). The lung carcinoma cell line was chosen for further molecular studies that include Real-time PCR, Flow-cytometry, Cytochrome c oxidase, and ELISA assay. SEM and TEM tool were used to follow the morphological changes occurred on the cell surface.

A novel cold-water-soluble polysaccharide (BEP), with a molecular weight of 6.0 × 10 6  Da, was isolated from Boletus edulis. BEP consists of galactose, glucose, xylose, mannose, glucuronic, and galacturonic acid in a ratio of 0.34:0.28:0.28:2.57:1.00:0.44. The IR results showed that BEP was an acid polysaccharide, containing α-type and β-type glucoside bonds. MTT assay showed BEP could inhibit cell proliferation significantly. Morphological observation demonstrated that BEP-treated MDA-MB-231 and Ca761 cells exhibited typical apoptotic morphological features. Flow cytometry analysis revealed that BEP caused mitochondrial membrane potential collapse. Annexin V-FITC/PI staining indicated that BEP induced apoptosis of MDA-MB-231 and Ca761 cells through cell block in S phase and G 0 /G 1 phase, respectively. Western blot results showed that BEP could increase the Bax/Bcl-2 ratios, promote the release of cytochrome C, and activate the expression of caspase-3 and caspase-9 in MDA-MB-231 and Ca761 cells. In conclusion, our results demonstrated that BEP could inhibit the proliferation of breast cancer cells and induce apoptosis through mitochondrial pathways.

Multiple myeloma has always been an important health problem in human beings due to its high morbidity, high mortality, and lack of effective therapeutic drugs. This study investigated the anticancer effect and mechanism of the newly synthesized small molecule compound CPUC002 on multiple myeloma. Our results confirmed that CPUC002 inhibited proliferation and induced G0/G1 cell cycle arrest in multiple myeloma cells. Moreover, CPUC002 also induced apoptosis by mitochondrial pathway and exogenous pathway. In mechanism, CPUC002 triggered apoptosis by stabilizing p53 in NCI-H929 cells which expressed wt-p53. Knockdown of p53 partially suppressed CPUC002-induced apoptosis. This suggests that there are other molecular mechanisms underlying CPUC002's antitumor effect. Further studies showed that the CPUC002 also inhibited the STAT3 signaling pathway, while knockdown of STAT3 abolished CPUC002-induced apoptosis and cell cycle arrest. In vivo, CPUC002 has significant antitumor activity through the same mechanism as our in vitro studies, and is highly safe in xenograft models. Together these findings indicate that CPUC002 induces apoptosis and G0/G1 cell cycle arrest in multiple myeloma cells by stabilizing p53 and inhibiting the STAT3 signaling pathway.

eIF4E plays key roles in protein synthesis and tumorigenesis. It is phosphorylated by the kinases MNK1 and MNK2. Binding of MNKs to eIF4G enhances their ability to phosphorylate eIF4E. Here, we show that mTORC1, a key regulator of mRNA translation and oncogenesis, directly phosphorylates MNK2 on Ser74. This suppresses MNK2 activity and impairs binding of MNK2 to eIF4G. These effects provide a novel mechanism by which mTORC1 signaling impairs the function of MNK2 and thereby decreases eIF4E phosphorylation. MNK2[S74A] knock-in cells show enhanced phosphorylation of eIF4E and S6K1 (i.e., increased mTORC1 signaling), enlarged cell size, and increased invasive and transformative capacities. MNK2[Ser74] phosphorylation was inversely correlated with disease progression in human prostate tumors. MNK inhibition exerted anti-proliferative effects in prostate cancer cells in vitro. These findings define a novel feedback loop whereby mTORC1 represses MNK2 activity and oncogenic signaling through eIF4E phosphorylation, allowing reciprocal regulation of these two oncogenic pathways.

Myricetin is categorized under the secondary metabolite flavonoid which includes a diverse range of consumable plant parts, and it has a potential against several classes of cancer including cancers and tumors. In the present study, the anticancer potential of the unique flavonoid-myricetin in A549 lung cancer cells was evaluated. Among different doses of myricetin, 73 μg/ml was more effective to prevent the cancer cell growth. It also promoted sub-G1 phase aggregation of cells and a equivalent decrease in the fraction of cells entering the S and subsequent phase which indicates apoptotic cell death. Myricetin generated enormous free radicals and, altered the potential of mitochondrial membrane in A549 cells as paralleled to untreated cells. In addition, myricetin treatment intensified the expression of P53 and relegated the expression of EGFR in A549 cells. These results suggested that myricetin exhibits cytotoxic potential by arresting the progression of cell cycle and ROS-dependent mitochondria-mediated mortality in cancer A549 lung cancer cells and it would be useful to develop as a drug candidate for lung cancer therapeutics. In silico experiments were carried out against human EGFR and P53 tumor suppressor protein to gain more insights into the binding mode of the myricetin may act as significant potential for anticancer therapy.

Purpose: Acute lymphoblastic leukemia (ALL) is an aggressive hematological cancer with limited therapeutic options for adult patients. Aurora kinases have drawn attention as potential targets in hematological neoplasms due to their high expression and biological functions. Aurora kinase A (AURKA) and AURKB are essential for a successful mitosis, acting in spindle mitotic organization and cytokinesis. Reversine is a synthetic purine analog that acts as a multi-kinase inhibitor with anti-neoplastic activity by targeting AURKA and AURKB., Methods: ALL patient gene expression data were retrieved from the Amazonia!, Database: For functional assays, Jurkat (T-ALL) and Namalwa (B-ALL) cells were exposed to increasing concentrations of reversine and submitted to various cellular and molecular assays., Results: We found that AURKB expression was higher in ALL patient samples compared to normal lymphocytes (p < 0.0001). The ALL cell lines tested displayed aberrant AURKA and AURKB expression. In Jurkat and Namalwa cells, reversine reduced cell viability in a dose- and time-dependent manner (p < 0.05). Reversine also significantly reduced the viability of primary ALL cells. Reversine induced apoptosis and autophagy, and reduced cell proliferation in both cell lines (p < 0.05). Mitotic catastrophe markers, including cell cycle arrest at G 2 /M, increased cell size and DNA damage, were observed upon reversine exposure. Short- and long-term treatment with reversine inhibited autonomous clonogenicity (p < 0.05). At the molecular level, reversine reduced AURKB activity, induced SQSTM1/p62 consumption, and increased LC3BII and γ-H2AX levels. In Namalwa cells, reversine modulated 25 out of 84 autophagy-related genes, including BCL2, BAD, ULK1, ATG10, IRGM and MAP1LC3B, which indicates that reversine acts by initiating and sustaining autophagy signals in ALL cells., Conclusions: From our data we conclude that reversine reduces the viability of ALL cells by triggering multiple cell death mechanisms, including apoptosis, mitotic catastrophe, and autophagy. Our findings highlight reversine as a potential anticancer agent for ALL.

Hepatocellular carcinoma (HCC) is the most prevalent type of tumor among primary liver tumors and is the second highest cause of cancer-related deaths worldwide. Current therapies are controversial, and more research is needed to identify effective treatments. A new synthetic compound, potassium 5-cyano-4-methyl-6-oxo-1,6-dihydropyridine-2-olate (CPBMF65), is a potent inhibitor of the human uridine phosphorylase-1 (hUP1) enzyme, which controls the cell concentration of uridine (Urd). Urd is a natural pyrimidine nucleoside involved in cellular processes, such as RNA synthesis. In addition, it is considered a promising biochemical modulator, as it may reduce the toxicity caused by chemotherapeutics without impairing its anti-tumor activity. Thus, the objective of this study is to evaluate the effects of CPBMF65 on the proliferation of the human hepatocellular carcinoma cell line (HepG2). Cell proliferation, cytotoxicity, apoptosis, senescence, autophagy, intracellular Urd levels, cell cycle arrest, and drug resistance were analyzed. Results demonstrate that, after incubation with CPBMF65, HepG2 cell proliferation decreased, mainly through cell cycle arrest and senescence, increasing the levels of intracellular Urd and maintaining cell proliferation reduced during chronic treatment. In conclusion, results show, for the first time, the ability of a hUP1 inhibitor (CPBMF65) to reduce HepG2 cell proliferation through cell cycle arrest and senescence.

Purpose: Hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC), which has a male predominance, lacks effective therapeutic options. Previously, the cardiac glycoside analogue bufalin has been found to inhibit HBV infection and HCC development. As yet, however, its molecular role in HBV-associated HCC has remained obscure., Methods: Colony formation and soft agar assays, xenograft and orthotopic mouse models and HBV X protein (HBx) transgenic mice with exposure to diethylnitrosamine were used to evaluate the effect of bufalin on HBV-associated HCC growth and tumorigenicity. HBx-induced oncogenic signaling regulated by bufalin was assessed using PCR array, chromatin immunoprecipitation, site-directed mutagenesis, luciferase reporter, transcription and protein expression assays. Synergistic HCC therapeutic effects were examined using combinations of bufalin and sorafenib., Results: We found that bufalin exerted a more profound effect on inhibiting the proliferation of HBV-associated HCC cells than of non HBV-associated HCC cells. Bufalin significantly inhibited HBx-induced malignant transfromation in vitro and tumorigenicity in vivo. Androgen receptor (AR) signaling was found to be a target of bufalin resistance to HBV-associated hepatocarcinogenesis. We also found that bufalin induced both AR dephosphorylation and cell cycle-related kinase (CCRK) degradation to inhibit β-catenin/TCF signaling, which subsequently led to cell cycle arrest via cyclin D1 down-regulation and p21 up-regulation, resulting in HCC regression. Furthermore, we found that bufalin reduced > 60% diethylnitrosamine-induced hepatocarcinogenesis in HBx transgenic mice, and improved the sensitivity of refractory HBV-associated HCC cells to sorafenib treatment., Conclusion: Our results indicate that bufalin acts as a potential anti-HCC therapeutic candidate to block HBx-induced AR/CCRK/β-catenin signaling by targeting AR and CCRK, which may provide a novel strategy for the treatment of HBV-associated HCC.

Background: The advent of immune checkpoint inhibitors has dramatically changed the treatment landscape of many different tumor types. In the clinical routine, humanized antibodies against the immune checkpoints cytotoxic T‑lymphocyte associated protein 4 (CTLA-4) and programmed cell death 1/programmed cell death ligand 1 (PD1/PD-L1) are generally applied., Objective: This article provides an overview of the treatment landscape with immune checkpoint inhibitors, especially for solid tumors in oncology., Material and Methods: Description and discussion of recent trial results as well as current treatment recommendations and treatment approval indications., Results: In the clinical routine seven different immune checkpoint inhibitors are applied in oncology: one anti-CTLA‑4 antibody, three anti-PD1 antibodies and three anti-PD-L1 antibodies. On the US market FDA approval for 17 different tumor entities and one agnostic indication (tumors with mismatch repair mechanism deficiency/high microsatellite instability). Long-term remission can be achieved for ca. two thirds of patients with tumor response., Conclusion: Clinical benefits for only a part of patients treated with immune checkpoint inhibitors. The understanding of primary and secondary mechanisms of resistance to immune checkpoint inhibitors has just begun to evolve. Combination strategies of immune checkpoint inhibitors with e.g. chemotherapy, new immune checkpoint inhibitors (e.g. anti-LAG3 antibody) or targeted therapies (e.g. CDK4/6, PARP inhibitors) to improve efficacy are under clinical investigation. Reliable and predictive biomarkers are urgently needed.

Purpose: Although doxorubicin is widely used to treat cancer, severe side effects limit its clinical use. Combination of standard chemotherapy with natural products can increase the efficacy and attenuate the side effects of current therapies. Here we studied the anticancer effects of a combined regimen comprising doxorubicin and [10]-gingerol against triple-negative breast cancer, which does not respond to hormonal or targeted therapies., Methods: Cytotoxicity was evaluated by MTT assay, cell cycle progression and apoptosis were analyzed by flow cytometry and signaling pathways were analyzed by Western blotting in human and murine triple negative breast cancer cell systems. The anticancer/antimetastatic and toxic effects of the combined regimen was evaluated using syngeneic and xenograft orthotopic models., Results: The combination of doxorubicin and [10]-gingerol significantly increased the number of apoptotic cells, compared to each compound alone. In 4T1Br4 cells, the combined regimen was the only condition able to increase the levels of active caspase 3 and γH2AX and to decrease the level of Cdk-6 cyclin. In vivo, doxorubicin (3 mg/Kg, D3) and [10]-gingerol (10 mg/Kg, G10) resulted in a significant reduction in the volume of primary tumors and a decrease in the number of circulating tumor cells (CTCs). Interestingly, only the combined regimen led to decreased tumor burdens to distant organs (i.e., metastasis) and reduced chemotherapy-induced weight loss and hepatotoxicity in tumor-bearing animals. Likewise, in a xenograft model, only the combined regimen was effective in significantly reducing the primary tumor volume and the prevalence of CTCs., Conclusions: Our data indicate that [10]-gingerol has potential to be used as a neoadjuvant or in combined therapy with doxorubicin, to improve its anticancer activity.

Chemotherapy has always been the first therapeutic option for patients with advanced non-small cell lung cancer (NSCLC) with untreatable oncogenic mutations. However, chemotherapy has demonstrated limited success and is associated with severe side effects. This research aimed to investigate the antitumor efficacy and cytotoxic safety of the conjugate Z HER2:V2 -pemetrexed, a novel targeted chemotherapeutic drug. In this context, human epidermal growth factor receptor 2 (HER2) + A549 lung xenografts were treated using Z HER2:V2 -pemetrexed, pemetrexed or physiological saline. Therapeutic efficacy was monitored by single photon emission computed tomography (SPECT) imaging using the 99m Tc-labeled Z HER2:V2 -pemetrexed conjugate and further confirmed by performing apoptosis assays using flow cytometry analysis and hematoxylin-eosin (H&E) staining. To evaluate the expression of HER2 in tumor tissues, immunohistochemistry was performed, accompanied by quantitative analysis using flow cytometry. A toxicological evaluation was also conducted. Imaging with 99m Tc-Z HER2:V2 -pemetrexed demonstrated that in HER2+ A549 models, Z HER2:V2 -pemetrexed showed better antineoplastic effects than pemetrexed. Compared with pemetrexed, the results from the pathological and flow cytometry analyses also revealed that Z HER2:V2 -pemetrexed exhibits high antitumor activity against A549 tumors, inducing necrosis, apoptosis and cell cycle arrest. In addition, the clinical signs of toxicity in the Z HER2:V2 -pemetrexed treated group were reduced compared with those in the pemetrexed treated group. These data revealed that the Z HER2:V2 -pemetrexed conjugate encompasses promising targeted antitumor activity against HER2-positive lung adenocarcinoma, with reduced side effects compared with pemetrexed. Thus, the Z HER2:V2 -pemetrexed conjugate may serve as a novel molecular agent with tremendous clinical breakthrough potential in the diagnosis and treatment of HER2-positive lung adenocarcinoma.

Protein neddylation, a process of conjugating neural precursor cell expressed, developmentally downregulated 8 (NEDD8) to substrates, plays a tumor-promoting role in lung carcinogenesis. Our previous study showed MLN4924, an inhibitor of NEDD8 activating enzyme (E1), significantly inhibits the growth of multiple cancer cells. However, resistance can develop to MLN4924 by mutation. Therefore, it is important to further understand how NEDD8 acts in lung cancer. In the present study, we demonstrated NEDD8 is overactivated in lung cancers and confers a worse patient overall survival. Furthermore, we report that in lung adenocarcinoma cells, NEDD8 depletion significantly suppressed lung cancer cell growth and progression both in vitro and in vivo. Mechanistic studies revealed that NEDD8 depletion induced the accumulation of a panel of tumor-suppressive cullin-RING ubiquitin ligase substrates (e.g., p21, p27, and Wee1) via blocking their degradation, triggering cell cycle arrest at G 2 phase, thus inducing apoptosis or senescence in a cell-line-dependent manner. The present study demonstrates the role of NEDD8 in regulating the malignant phenotypes of lung cancer cells and further validates NEDD8 as a potential therapeutic target in lung cancer.

We studied the effects of berberine on the proliferation, apoptosis, and migration of skin melanoma A375 cells, as well as cell cycle-related miRNAs and their target genes, CDK1, CDK2, and cyclins D1 and A. The inhibitory effect of berberine on the growth of A375 cells was evaluated by MTT assay. Cell apoptosis was detected by trypan blue staining. Cell migration was assessed by the scratch test. Cell cycle phases were determined by flow cytometry. The levels of miRNA-582-5p and miRNA-188-5, and mRNA of their target genes encoding CDK1, CDK2, and cyclins D1 and A were measured by qRT-PCR. The expression of cell cycle-related proteins (CDK1, CDK2, and cyclins D1 and A) was determined by Western blotting. Berberine inhibited the proliferation of A375 cells in a time- and dose-dependent manner and significantly and dose-dependently enhanced cell apoptosis. Scratch assay showed an inhibitory effect of berberine on migration of A375 cells. Berberine in low concentrations (20 and 40 μM) caused cell cycle arrest in the S and G2/M phases, while treatment with high concentrations of berberine (60 and 80 μM) arrested cell-cycle in the G2/M phase. The increase in berberine concentration led to an increase in miRNA-582-5p and miRNA-188-5p expression and a decrease in the expression of mRNA for the corresponding target genes encoding CDK1, CDK2, and cyclins D1 and A. Western blotting also revealed reduced expression of CDK1, CDK2, and cyclins D1 and A. Thus, berberine suppressed the growth and migration of human melanoma cells and promoted their apoptosis. Berberine can increase the expression of cell cycle-related miRNAs and cause degradation of the corresponding target genes, thereby blocking the cell cycle progression and inhibiting the melanoma A375 cells.

In the present study, the antitumoral properties of a series of 7-chloroquinoline-1,2,3-triazoyl-carboxamides (QTCA) were investigated by analyzing their cytotoxic activities against human bladder cells (5637; grade II carcinoma). In addition, their effects on cell viability, cell cycle arrest mechanisms, apoptosis induction, in silico molecular docking, and detection of pro-apoptotic and anti-apoptotic proteins were evaluated. The cytotoxicity assay identified major dose- and time-dependent cytotoxic effects in 5637 cells after they were exposed to treatment with QTCA, only minimal effects were observed on normal cells. A live/dead assay confirmed that significant cell death, arrest in the G0/G1 phase and apoptosis were associated with treatment by 1-(7-Chloroquinolin-4-yl)-5-methyl-N-phenyl-1H-1,2,3-triazole-4-carboxamide (QTCA-1) and 1-(7-Chloroquinolin-4-yl)-N-(4-fluorophenyl)-5-methyl-1H-1,2,3-triazole-4-carboxamide (QTCA-4). The in silico results indicated that these compounds acted through different mechanisms for the induction of cell cycle arrest and apoptosis. Western blotting confirmed the binding of the QTCAs to pro- and anti-apoptotic proteins. In conclusion, QTCA-1 and QTCA-4 are promising candidates for inducing cytotoxicity, cell cycle arrest, and apoptosis in human bladder cancer cells.

The bromodomain and extra-terminal domain (BET) family of proteins, especially bromodomain-containing protein 4 (BRD4), has emerged as exciting anti-tumor targets due to their important roles in epigenetic regulation. Therefore, the discovery of BET inhibitors with promising anti-tumor efficacy will provide a novel approach to epigenetic anticancer therapy. Recently, we discovered the new BET inhibitor compound 171, which is derived from a polo-like kinase 1 (PLK1)-BRD4 dual inhibitor based on our previous research. Compound 171 was found to maintain BET inhibition ability without PLK1 inhibition, and there was no selectivity among BET family members. The in vitro and in vivo results both indicated that the overall anti-tumor activity of compound 171 was improved compared with the (+)-JQ-1 or OTX-015 BET inhibitors. Furthermore, we found that compound 171 could regulate the expression of cell cycle-regulating proteins including c-Myc and p21 and induce cell cycle arrest in the G 0 /G 1 phase. However, compound 171 only has a quite limited effect on apoptosis, in considering that apoptosis was only observed at doses greater than 50 μM. To determine the mechanisms underlying cell death, proliferation activity assay was conducted. The results showed that compound 171 induced clear anti-proliferative effects at doses that no obvious apoptosis was induced, which indicated that the cell cycle arresting effect contributed mostly to its anti-tumor activity. The result of this study revealed the anti-tumor mechanism of compound 171, and laid a foundation for the combination therapy in clinical practice, if compound 171 or its series compounds become drug candidates in the future.

The anticancer activity of a series of novel synthesized, hydroxypyridone-based metal chelators (analogues of L-mimosine) was evaluated in an in vitro model of melanoma consisting of malignant melanoma (A375), non-melanoma epidermoid carcinoma (A431) and immortalized non-malignant keratinocyte (HaCaT) cells. More specifically, we have demonstrated that the L-enantiomer of a methylated analogue of L-mimosine (compound 22) can exert a potent anticancer effect in A375 cells when compared to either A431 or HaCaT cells. Moreover, we have demonstrated that this analogue has the ability to i) promote increased generation of reactive oxygen species (ROS), ii) activate both intrinsic and extrinsic apoptosis and iii) induce perturbations in cell cycle growth arrest. Our data highlights the potential of compound 22 to act as a promising therapeutic agent against an in vitro model of human malignant melanoma.

Vitamin K 3 , also known as menadione, is a synthetic lipid-soluble 2-methyl-1,4- naphthoquinone analogs of vitamin K. The vitamin K derivatives exhibit potent cytotoxicity against several cancer cell lines through ROS induction and mitochondrial dysfunction. We investigated vitamin K 3 -inspired derivatives as potential apoptotic inducers and analyzed their mechanisms beyond apoptosis. The cytotoxicity of a panel of vitamin K 3 analogs was screened against 10 doxorubicin-sensitive and -resistant cancer cell lines overexpressing ATP-binding cassette transporters (P-glycoprotein, ABCB5, BCRP) or oncogenes (ΔEGFR) or with knockout of tumor suppressors (p53), Cell cycle arrest, apoptosis, cell migration, and microtubule formation were further investigated. The online tool SwissTargetPrediction was utilized for target prediction. Among the screened compounds, one vitamin K 3 thio-derivative (No. 45, VKT-1) exhibited the most potent cytotoxicity specifically against both drug-sensitive and -resistant cancer cell lines. In addition, VKT-1 arrested the cells at the G2/M phase and induced apoptosis as detected by flow cytometry. As predicted by SwissTargetPrediction, VKT-1 targeted microtubule-associated tau protein. Indeed, VKT-1 dramatically inhibited cell migration and microtubule formation in vitro. In conclusion, the synthetic vitamin K 3 thio-derivative (VKT-1) inhibited doxorubicin-sensitive and -resistant tumor cells by cell arrest, apoptosis induction, as well as, migration inhibition, and microtubule deterioration of U2OS-GFP-α-tubulin cells.

The majority of patients with Philadelphia-negative myeloproliferative neoplasms (MPNs) harbor a gain of function mutation V617F in Janus kinase (JAK) 2. Although JAK2 inhibitors such as ruxolitinib have been shown to be clinically efficacious, the hematological toxicity and eventual drug resistance limit its use as monotherapy. Other gene mutations or dysregulation correlated with the disease phenotype and prognosis have been found to contribute to the complexity and heterogeneity of MPNs, giving rise to an increasing demand for combination therapies. Here, we combine ruxolitinib and the histone deacetylase inhibitor vorinostat as a rational combination strategy for MPNs. We tested the combination of ruxolitinib and vorinostat in cells with the JAK2V617F mutation, such as HEL cells, c-Kit + cells from JAK2V617F transgenic mice and bone marrow mononuclear cells (BMMNCs) from patients with MPN. Our results showed significant synergistic effects of this combination strategy. Cotreatment with ruxolitinib and vorinostat synergistically induced apoptosis, cell cycle arrest and inhibition of the colony-forming capacity of HEL cells by attenuating the JAK/signal transducer and activator of transcription (STAT) and protein kinase-B (AKT) signaling pathways. In particular, cotreatment with ruxolitinib and vorinostat prevented the formation of large colonies of colony-forming unit-granulocyte/erythroid/macrophage/megakaryocytes (CFU-GEMMs) and colony-forming unit-granulocyte/macrophages (CFU-GMs) derived from the BMMNCs of patients with MPN. Taken together, these data provided preclinical evidence that the combination of ruxolitinib and vorinostat is a potential dual-target therapy for patients with MPN.

Microtubule targeting agents (MTAs) are extensively used in cancer treatment and many have achieved substantial clinical success. In recent years, targeting microtubules to inhibit cell division has become a widespread pharmaceutical approach for treatment of various cancer types. Nevertheless, the development of multidrug resistance (MDR) in cancer remains a major obstacle for successful application of these agents. Herein, we provided the evidence that CKT0353, α-branched α,β-unsaturated ketone, possesses the capacity to successfully evade the MDR phenotype as an MTA. CKT0353 induced G 2 /M phase arrest, delayed cell division via spindle assembly checkpoint activation, disrupted the mitotic spindle formation and depolymerized microtubules in human breast, cervix, and colorectal carcinoma cells. Molecular docking analysis revealed that CKT0353 binds at the nocodazole binding domain of β-tubulin. Furthermore, CKT0353 triggered apoptosis via caspase-dependent mechanism. In addition, P-glycoprotein overexpressing colorectal carcinoma cells showed higher sensitivity to this agent when compared to their sensitive counterpart, demonstrating the ability of CKT0353 to overcome this classic MDR mechanism involved in resistance to various MTAs. Taken together, these findings suggest that CKT0353 is an excellent candidate for further optimization as a therapeutic agent against tumors with MDR phenotype.

Splicing of pre-mRNA into functional mRNA, carried out by the spliceosome, represents a crucial step in eukaryotic gene expression. Mutations and other deregulation in some of the spliceosome components have been identified in multiple pathologies, including hematological malignancies. In this context, we evaluated the therapeutic potential of a splicing inhibitor, Pladienolide B (Pla-B), in two erythroleukemia cell lines. HEL and K562 cell lines were incubated with increasing doses of Pla-B in single and daily administration. Cell viability and density were evaluated using trypan blue assay. Flow cytometry was used to evaluate cell death, cell cycle, and caspase activity. NGS analysis was performed to assess the mutational status of 4 splicing-related genes (SF3B1, U2AF1, ZRSR2 and SRSF2). Expression levels of SF3B1 and unspliced DNAJB1 were evaluated by qPCR. Pla-B significantly decreased the viability and proliferation of both cell lines in time, dose, administration schedule, and cell line-dependent manner. HEL cells were more sensible to Pla-B (IC 50  = 1.5 nM) than K562 (IC 50  = 25 nM), with an IC 50 almost 17 times lower. Pla-B induced cell death, mainly by apoptosis, and cell cycle arrest in G 0 /G 1 phase. No mutations were found in any of the analyzed genes, suggesting that the observed cytotoxic effect is independent of the spliceosome mutations. Splicing modulator Pla-B showed high antitumor activity against HEL and K562 cell lines, inducing apoptosis and cell cycle arrest. These data suggest that Pla-B might represent a new therapeutic approach for erythroleukemia.

Tetrahydropyridinol derivatives were recently reported to exhibit good biological activities, and the incorporation of fluorine into organic molecules may have profound effects on their physical and biological properties. Therefore, we investigated the anticancer activities of six fluorinated tetrahydropyridinol derivatives that we synthesized previously. We found that only one compound, 3,3-difluoro-2,2-dimethyl-1,6-diphenyl-5-tosyl-1,2,3,6-tetrahydropyridin-4-ol, showed significant antiproliferative activity on human hepatocellular carcinoma HepG2 and HMCCLM3 cells (the IC 50 values were 21.25 and 29.07 μM, respectively). We also found that this compound mediated cell cycle arrest in the G0/G1 phase at 30-40 μM. Western blot analysis demonstrated that the cell cycle arrest induced by this compound in HepG2 and HMCCLM3 cells was associated with a significant decrease in Cdc2 and cyclin B1, which led to the accumulation of the phosphorylated-Tyr 15 (inactive) form of Cdc2 and low expression of M phase-promoting factor (cyclin B1/Cdc2). Moreover, cells treated with this compound exhibited decreased expression of cyclin-dependent kinase (CDK)-activating kinase (CDK7/cyclin H). This compound also induced cell apoptosis via activation of caspase-3. A xenograft model in nude mice demonstrated anti-liver cancer activity and the mechanism of action of this compound. These findings indicated that the anticancer effect of this compound was partially due to G0/G1 cell cycle arrest via inhibition of CDK7-mediated expression of Cdc2, and this compound may be a promising anticancer candidate for further investigation.

Purpose: Gemcitabine (GEM)-based chemotherapy is the first-line treatment for locally advanced pancreatic cancer. GEM resistance, however, remains a significant clinical challenge. Here, we investigated whether exosomes derived from GEM-resistant pancreatic cancer stem cells (CSCs) mediate cell-cell communication between cells that are sensitive or resistant to GEM and, by doing so, regulate drug resistance., Methods: GEM-sensitive BxPC-3-derived Bx S and PANC-1 pancreatic cancer cells were cultured with exosomes extracted from CSCs isolated from GEM-resistant BxPC-3-derived Bx R cells (Bx R -CSC). The effect of exosomes on drug resistance, cell cycle progression, apoptosis and miRNA expression was evaluated in Bx S and PANC-1 cells. Relevant miRNAs associated with GEM resistance were identified and the role of miR-210 in conferring drug resistance was examined in vitro and in vivo., Results: Bx R -CSC-derived exosomes induced GEM resistance, inhibited GEM-induced cell cycle arrest, antagonized GEM-induced apoptosis, and promoted tube formation and cell migration in Bx S and PANC-1 cells. Elevated miR-210 expression levels were detected in Bx R -CSCs and Bx R -CSC-derived exosomes compared to those in Bx S -CSCs and Bx S -CSC-derived exosomes. In addition, increased expression levels of miR-210 were observed in Bx S and PANC-1 cells cultured with Bx R -CSC-derived exosomes upon exposure to GEM in a dose-dependent manner. Also, a series of biological changes was observed in Bx S cells after transfection with miR-210 mimics, including activation of the mammalian target of rapamycin (mTOR) signaling pathway, and these changes were similar to those triggered by Bx R -CSC-derived exosomes., Conclusions: Our findings suggest that exosomes derived from GEM-resistant pancreatic cancer stem cells mediate the horizontal transfer of drug-resistant traits to GEM-sensitive pancreatic cancer cells by delivering miR-210.

Although it's widely known that targeted therapy against angiogenesis and immunotherapy agents showed survival benefit over chemoradiotherapy in advanced or metastatic renal cell carcinoma, some patients still cannot receive a satisfied prognosis. We performed a systematic review and meta-analysis to explore the efficacy and safety of anti-angiogenic agents combined with immune checkpoint inhibitors. We conducted a search for randomized controlled trials in Pubmed, Embase, Cochrane, and major conference. Enrolled eligible studies and extracted data were completed by two investigators to compare OS, PFS, and ORR both in PD-L1 and ITT subset. Then, we calculated the pooled RR and 95% CI of all-grade and high-grade adverse effects to study its safety. Besides, we assessed the heterogeneity through subgroup and sensitivity analysis. A total of three RCTs covering 2662 patients were enrolled. In PFS analysis, the estimated HR for ITT subset was 0.74 with 95% CI of 0.65 to 0.84 and for PD-L1 subset was 0.65 with 95% CI of 0.56 to 0.76. And in OS analysis, the result was 0.74 with 95% CI of 0.53 to 1.03 in ITT subset and 0.74 with 95% CI of 0.56 to 0.96 in PD-L1 subset. As for ORR analysis, combination therapy showed advantage rather than monotherapy in ITT subset (RR 1.54; 95% CI 1.11 to 2.14), but conversely in PD-L1 positive subset (RR 1.64; 95% CI 0.94 to 2.84). Additionally, combination therapy failed to show obvious safety in most immune-related adverse events, whatever in all-grade or high grade.

ERK1/2 inhibitors are new promising anticancer drugs. The aim of this study was to investigate the effect of the combination of ERK2 inhibitor VX-11e and voreloxin on MOLM-14, K562, REH and MOLT-4 leukemia cell lines. We found that VX-11e alone and in combination with voreloxin significantly decreased ERK activation in all cell lines tested. To evaluate the interactions of the drugs, cells were treated for 24 h with VX-11e or voreloxin alone and in combination at fixed ratios based on IC 50 values. The combinatorial effects of both drugs were synergistic over a wide range of concentrations in MOLM-14, REH and MOLT-4 cell lines. In K562 cells, three effects were found to be additive, one antagonistic and only one synergistic. The results showed that incubation with both VX-11e and voreloxin inhibited the growth of leukemia cells, affected cell cycle and induced apoptosis. Furthermore, the molecular mechanism of these effects might be attributed to an increased expression of p21 and a decreased expression of survivin and NF-κB in all cell lines tested except from K562 cells. In conclusion, combination of VX-11e and voreloxin can exert a synergistic anticancer effect in leukemia cells.

Hepatic stellate cell (HSC) activation plays an indispensable role in hepatic fibrosis. Inducing apoptosis of activated HSCs can attenuate or reverse fibrogenesis. In this study, we initially found that oroxylin A (OA) protected CCl 4 -induced liver injury accompanied by endoplasmic reticulum stress (ERS) activation of HSCs in mice. In vitro, OA treatment markedly reduced fibrogenesis by modulating extracellular matrix synthesis and degradation. OA inhibited cell proliferation and induced cell cycle arrest of HSCs at S phase. Further, OA was observed to induce HSC apoptosis, as indicated by caspase activation. Using the eIF2α dephosphorylation inhibitor salubrinal, we found that ERS pathway activation was required for OA to induce HSC apoptosis. ERS-related proteins were significantly upregulated by OA treatment, and salubrinal abrogated the effects of OA on HSCs. Thus, we inferred that OA attenuated HSC activation by promoting ERS. In vivo, inhibition of ERS by salubrinal partly abrogated the hepatoprotective effect of OA in CCl 4 -treated mice. In conclusion, our findings suggest a role for ERS in the mechanism underlying amelioration of hepatic fibrosis by OA.

We tested the hypothesis that stimulation of adiponectin receptors with the synthetic agonist AdipoRon suppresses proliferation and induces apoptotic death in human high grade serous ovarian tumor cell lines and in ex vivo primary tumors, mediated by activation of 5' AMP-activated protein kinase (AMPK) and inhibition of mechanistic target of rapamycin (mTOR). We determined the effect of AdipoRon on high grade serous ovarian tumor cells lines (OVCAR3, OVCAR4, A2780) and ex vivo primary tumor tissue. Western blotting analysis was performed to examine changes in activation of AMPK and mTOR signaling and flow cytometry was utilized to examine changes in cell cycle progression. Immunofluorescence of cleaved caspase-3 positive cells and flow cytometry of annexin V positive cells were used to determine changes in apoptotic response. The CyQUANT proliferation assay was used to assess cell proliferation. AdipoRon treatment increased AMPK phosphorylation (OVCAR3 P = 0.01; A2780 P = 0.02) but did not significantly alter mTOR activity. AdipoRon induced G1 cell cycle arrest in OVCAR3 (+ 12.1%, P = 0.03) and A2780 (+ 12.0%, P = 0.002) cells. OVCAR3 and OVCAR4 cells treated with AdipoRon underwent apoptosis based on cleaved caspase-3 and annexin V staining. AdipoRon treatment resulted in a dose dependent decrease in cell number versus vehicle treatment in OVCAR3 (-61.2%, P < 0.001), OVCAR4 (-79%, P < 0.001), and A2780 (-56.9%, P < 0.001). Ex vivo culture of primary tumors treated with AdipoRon resulted in an increase in apoptosis measured with cleaved caspase-3 immunohistochemistry. AdipoRon induces activation of AMPK and exhibits an anti-tumor effect in ovarian cancer cell lines and primary tumor via a mTOR-independent pathway.

Fipronil (FPN) is a widely used phenylpyrazole pesticide that can kill pests by blocking γ-aminobutyric acid (GABA)-gated chloride channels. In addition, there are lack of studies on the effects of FPN on the female mammalian gametes. In this study, porcine oocytes were used to investigate the effects of FPN on the oocyte maturation process. The results showed that the first polar body extrusion rate significantly decreased (100 μM FPN vs. control, 18.64 ± 2.95% vs. 74.90 ± 1.50%, respectively), and oocytes were arrested at the germinal vesicle stage in 100 μM FPN group. Meanwhile, the FPN caused a significant increase in reactive oxygen species (ROS) levels and severe DNA damage inside the oocytes. Furthermore, apoptosis was enhanced along with decreases in mitochondrial membrane potential, BCL-xL, and the release of cytochrome C in FPN-treated group. Additionally, low CDK1 activity and delayed cyclin B1 degradation during germinal vesicle breakdown were found in the FPN-treated group, which resulted from the activation of ATM-P53-P21 pathway. In conclusion, FPN induces apoptosis and cell cycle arrest in porcine oocyte maturation because of increased ROS levels and DNA damage. This suggests that the FPN in the environment may have potential detrimental effects on the female mammalian reproductive system.

Plants are important sources of biologically active compounds and they provide unlimited opportunities for the discovery and development of new drug leads, including new chemotherapeutics. Miconidin acetate (MA) is a hydroquinone derivative isolated from E. hiemalis. In this study we demonstrated that MA was cytotoxic against acute leukemia (AL), solid tumor cells and cancer stem cells, with the strongest effect exhibited against AL. Furthermore, it was non-cytotoxic against non-tumor cells and did not cause significant hemolysis. MA blocks the G2/M phase and causes cytostatic effects, acting in a similar way to dexamethasone by increasing PML expression. The compound also triggered intrinsic and extrinsic apoptosis by modulating Bax, FasR and survivin expression. This led to an extensive mitochondrial damage that resulted in AIF, cytochrome c and endonuclease G release, caspase-3 and PARP cleavage and DNA fragmentation. We have further demonstrated that MA was strongly cytotoxic against neoplastic cells collected from patients with different AL subtypes. Interestingly, MA increased the cytotoxic effect of chemotherapeutics cytarabine and vincristine. This study indicates that MA may be a new agent for AL and highlights its potential as a new source of anticancer drugs. Graphical abstract MA blocks G2/M phase with PML expression and KI67 inhibition, ROS generation and intrinsic and extrinsic apoptosis, leading to mitochondrial damage, caspase 3 and PARP cleavage and DNA fragmentation.

Several species of the Annonaceae plants have been used as complementary medicine for cancer-associated illnesses in some ethnic groups of northern Thailand. This study investigated the cytotoxic and cytostatic activity of methanolic extracts derived from the stems of these plants, including Uvaria longipes (Craib) L.L.Zhou, Y.C.F.Su & R.M.K.Saunders, Artabotrys burmanicus A.DC, Marsypopetalum modestum (Pierre) B.Xue & R.M.K.Saunders, and Dasymaschalon sp. Cell death induction of seven human cancer cell lines and cell cycle analyses were assessed by Annexin V and/or propidium iodide (PI) staining and analyzed by flow cytometry. Treatment of cancer cell lines with the extract of four Annonaceae plants resulted in various cytotoxic activities depending on cell type. The extract of U. longipes exhibited the highest cytotoxic activity capable of inducing cell death of several cancer cell lines, particularly against hepatocellular carcinoma cell lines (HepG2 and Hep3B). This extract was capable of inducing cell cycle arrest at the SubG1 phase. Phytochemical screening of all the extracts revealed the presence of alkaloids, sterols, tannins, anthraquinone glycoside, coumarin, and flavonoids. Determination of active compounds by high-performance liquid chromatography standards revealed bullatacin and asiminecin in all the extracts. The extract of Annonaceae stem or its compounds may provide an opportunity for the development of new therapies against cancer.

Depression is a serious medical condition, typically treated by antidepressants. Conventional monotherapy can be effective only in 60-80% of patients, thus modern psychiatry deals with the challenge of new methods development. At the same moment, interactions between antidepressants and the occurrence of potential side effects raise serious concerns, which are even more exacerbated by the lack of relevant data on exact molecular mechanisms. Therefore, the aims of the study were to provide up-to-date information on the relative mechanisms of action of single antidepressants and their combinations. In this study, we evaluated the effect of single and combined antidepressants administration on mouse hippocampal neurons after 48 and 96 h in terms of cellular and biochemical features in vitro. We show for the first time that co-treatment with amitriptyline/imipramine + fluoxetine initiates in cells adaptation mechanisms which allow cells to adjust to stress and finally exerts less toxic events than in cells treated with single antidepressants. Antidepressants treatment induces in neuronal cells oxidative and nitrosative stress, which leads to micronuclei and double-strand DNA brakes formation. At this point, two different mechanistic events are initiated in cells treated with single and combined antidepressants. Single antidepressants (amitriptyline, imipramine or fluoxetine) activate cell cycle arrest resulting in proliferation inhibition. On the other hand, treatment with combined antidepressants (amitriptyline/imipramine + fluoxetine) initiates p16-dependent cell cycle arrest, overexpression of telomere maintenance proteins and finally restoration of proliferation. In conclusion, our findings may pave the way to better understanding of the stress-related effects on neurons associated with mono- and combined therapy with antidepressants.

Introduction: Immune checkpoint inhibitors (ICPI), a breakthrough immunotherapy for cancer, can cause serious neurological adverse events (AEs). We aimed to investigate the characteristics of the neurological and related AEs associated with ICPI treatment, using a large pharmacovigilance database from Japan., Methods: We conducted disproportionality analysis using the Japanese Adverse Drug Event Report (JADER) database containing 566,698 patient cases recorded between April 2004 and March 2019, to detect neurological and related AE signals associated with ICPI treatment by calculating reporting odds ratio (ROR)., Results: Among 7604 cases with ICPI usage, we identified 583 cases (7.67%) with a significantly high reporting of neurological and related AEs (lower 95% of the ROR > 1), including myasthenia gravis (MG), inflammatory myositis, non-infectious encephalitis/myelitis, non-infectious meningitis, hypophysitis/hypopituitarism, and peripheral neuropathy including Guillain-Barre syndrome (GBS). Among the ICPI subtypes, when compared to nivolumab as a reference, number of hypophysitis, hypopituitarism, and meningitis reports from the use of ipilimumab and number of encephalitis/myelitis and meningitis reports from the use of anti-programmed cell death-ligand-1 (PD-L1) agents were significantly higher. Additionally, time to AE onset of symptoms post administration was short in meningitis (median 21 days), MG (median 28 days), myositis (median 28 days), and encephalitis/myelitis (median 32.5 days), while it was longer in peripheral neuropathy (median 42 days), hypophysitis (median 94 days), and hypopituitarism (median 112 days)., Conclusions: Our results showed characteristic features of neurological and related AEs associated with each ICPI subtype, reported in a large number of Japanese patients. This would help in prompt identification and treatment of neurological AEs associated with ICPI treatment.

Encorafenib, a new-generation BRAF inhibitor, has been approved by FDA for the treatment of melanoma in combination with binimetinib. However, the mechanism of the drug works in colorectal cancer (CRC) is still unclear. In this study, the suppression of growth of CRC cells by encorafenib was investigated. The effects of treatment of encorafenib on pathways linked to cancer were studied, and the effective inhibition of cell proliferation was documented. Our findings showed that cell migration was inhibited by encorafenib through a likely involvement of MPP and TIMP modulation. Furthermore, encorafenib treatment also induced cell cycle arrest. In addition, induction of apoptosis in CRC cells by elevating levels of PUMA. These observations indicate the potential therapeutic efficacy of encorafenib on CRC.

Cardiac remodeling characterized by cardiac fibrosis is a pathologic process occurring after acute myocardial infarction. Fibrosis can be ameliorated by interferon-gamma (IFN-γ), which is a soluble cytokine showing various effects such as anti-fibrosis, apoptosis, anti-proliferation, immunomodulation, and anti-viral activities. However, the role of IFN-γ in cardiac myofibroblasts is not well established. Therefore, we investigated the anti-fibrotic effects of IFN-γ in human cardiac myofibroblasts (hCMs) in vitro and whether indoleamine 2,3-dioxygenase (IDO), induced by IFN-γ and resulting in cell cycle arrest, plays an important role in regulating the biological activity of hCMs. After IFN-γ treatment, cell signaling pathways and DNA contents were analyzed to assess the biological activity of IFN-γ in hCMs. In addition, an IDO inhibitor (1-methyl tryptophan; 1-MT) was used to assess whether IDO plays a key role in regulating hCMs. IFN-γ significantly inhibited hCM proliferation, and IFN-γ-induced IDO expression caused cell cycle arrest in G0/G1 through tryptophan depletion. Moreover, IFN-γ treatment gradually suppressed the expression of α-smooth muscle actin. When IDO activity was inhibited by 1-MT, marked apoptosis was observed in hCMs through the induction of interferon regulatory factor, Fas, and Fas ligand. Our results suggest that IFN-γ plays key roles in anti-proliferative and anti-fibrotic activities in hCMs and further induces apoptosis via IDO inhibition. In conclusion, co-treatment with IFN-γ and 1-MT can ameliorate fibrosis in cardiac myofibroblasts through apoptosis.

Breast cancer is the most frequently diagnosed cancer among women worldwide. Here, recombinant human lactoferrin (rhLf) expressed in Pichia pastoris was tested for its potential cytotoxic activity on a panel of six human breast cancer cell lines. The rhLf cytotoxic effect was determined via a live-cell HTS imaging assay. Also, confocal microscopy and flow cytometry protocols were employed to investigate the rhLf mode of action. The rhLf revealed an effective CC 50 of 91.4 and 109.46 µg/ml on non-metastatic and metastatic MDA-MB-231 cells, with favorable selective cytotoxicity index values, 11.68 and 13.99, respectively. Moreover, rhLf displayed satisfactory SCI values on four additional cell lines, MDA-MB-468, HCC70, MCF-7 and T-47D (1.55-3.34). Also, rhLf provoked plasma membrane blebbing, chromatin condensation and cell shrinkage in MDA-MB-231 cells, being all three apoptosis-related morphological changes. Also, rhLf was able to shrink the microfilaments, forming a punctuated cytoplasmic pattern in both the MDA-MB-231 and Hs-27 cells, as visualized in confocal photomicrographs. Moreover, performing flow cytometric analysis, rhLf provoked significant phosphatidylserine externalization, cell cycle arrest in the S phase and apoptosis-induced DNA fragmentation in MDA-MB-231 cells. Hence, rhLf possesses selective cytotoxicity on breast cancer cells. Also, rhLf caused apoptosis-associated morphologic changes, disruption of F-actin cytoskeleton organization, phosphatidylserine externalization, DNA fragmentation, and arrest of the cell cycle progression on triple-negative breast cancer MDA-MB-231 cells. Overall results suggest that rhLf is using the apoptosis pathway as its mechanism to inflict cell death. Findings warranty further evaluation of rhLf as a potential anti-breast cancer drug option.

Esophageal squamous cell carcinoma (ESCC) is one of the most serious life-threatening malignancies. Although chemotherapeutic targets and agents for ESCC have made much progress recently, the efficacy is still unsatisfactory. Therefore, there is still an unmet medical need for patients with ESCC. Here, we report the expression status of HDAC1 in human ESCC and matched paracancerous tissues, and the results indicated that HDAC1 was generally upregulated in ESCC specimens. Furthermore, we comprehensively assessed the anti-ESCC activity of a highly active HDAC1 inhibitor quisinostat. Quisinostat could effectively suppress cellular viability and proliferation of ESCC cells, as well as induce cell cycle arrest and apoptosis even at low treatment concentrations. The effectiveness was also observed in KYSE150 xenograft model when quisinostat was administered at tolerated doses (3 mg/kg and 10 mg/kg). Meanwhile, quisinostat also had the ability to suppress the migration and invasion (pivotal steps of tumor metastasis) of ESCC cells. Western blot analysis indicated that quisinostat exerted its anti-ESCC effects mainly through blockade of Akt/mTOR and MAPK/ERK signaling cascades. Overall, HDAC1 may serve as a potential therapeutic target for ESCC, and quisinostat deserves to be further assessed as a promising drug candidate for the treatment of ESCC.

An organometallic ruthenium(II) arene compound, Ru(η 6 -toluene)(PTA)Cl 2 (PTA = 1,3,5-triaza-7-phosphaadamantane), termed RAPTA-T, exerts promising antimetastatic properties. In this study, the effects of RAPTA-T on BRCA1-defective HCC1937 breast cancer cells have been investigated, and compared to its effects on BRCA1-competent MCF-7 breast cancer cells. RAPTA-T showed a very low cytotoxicity against both tested cells. Ruthenium is found mostly in the cytoplasmic compartment of both cells. Flow cytometric analysis reveals that the compound arrests the growth of both cells by triggering the G2/M phase that led to the induction of apoptosis. At equimolar concentrations, RAPTA-T causes much more cellular BRCA1 damage in HCC1937 than in MCF-7 cells, suppressing the expression of BRCA1 mRNA in both cell lines with the subsequent down-regulation of the BRCA1 protein. Interestingly, RAPTA-T exhibits an approximately fivefold greater ability to suppress the expression of the BRCA1 protein in HCC1937 than in MCF-7 cells. These data provide insights into the molecular mechanisms by which RAPTA-T exerts its effects on BRCA1-associated breast cancer cells.

Immune checkpoint inhibitors (ICIs) are novel anticancer agents, recently introduced with the aim of boosting the immune response against tumors. ICIs are monoclonal autoantibodies that specifically target inhibitory receptors on T cells: cytotoxic T lymphocyte antigen 4 (CTLA4), programmed death 1 (PD-1) and its ligand (PD-1L). ICIs also generate peculiar dysimmune toxicities, called immune-related adverse events (irAEs), that can potentially affect any tissue, and some may be life-threatening if not promptly recognized. The endocrine and metabolic side effects of ICIs are reviewed here, with a particular focus on their clinical presentation and management. They are among the most frequent toxicities (around 10%) and include hypophysitis, thyroid disorders, adrenalitis, and diabetes mellitus. Treatment is based on the replacement of specific hormone deficits, accompanied by immunosuppression (with corticosteroids or other drugs), depending on irAEs grade, often without the need of ICI withdrawal, except in more severe forms. Prompt recognition of endocrine and metabolic irAEs and adequate treatment allow the patients to continue a therapy they are benefiting from. Endocrinologists, as an integral part of the multidisciplinary oncologic team, need to be familiar with the unique toxicity profile of these anticancer agents. Practical recommendations for their management are proposed.

Microtubules (made up of α and β-tubulin subunits) play an essential role in the process of mitosis and cell proliferation, thus making them an ideal target for anticancer drugs discovery. Microtubule-targeted drugs, including taxanes and vinca alkaloids, can suppress microtubule dynamics, cause mitotic block and apoptosis, which have been widely used in the treatment of various cancers. There are three unique binding sites (taxanes, vinca alkaloids, and colchicine) in tubulin can be targeted to develop tubulin inhibitors. In this study, we selected the colchicine binding site in tubulin as our target. By performing molecular docking-based virtual screening combined with in vitro tubulin polymerization inhibition assay, we identified two novel and potent tubulin inhibitors (9 and 19). These two compounds arrested cell cycle progression at the G2/M phase and induced apoptosis at sub μM concentrations. In addition, they displayed potent antiproliferative activity with IC 50 values in the nM range. Finally, the probable binding modes of 9 and 19 were probed by molecular docking. These two compounds with novel scaffold will shed new light on the lead molecules discovery and the design of new microtubule-targeting agents (MTAs).

Oral squamous cell carcinoma (OSCC) is a common malignant tumor, accounting for about 7% of all malignant tumors. Palmatine hydrochloride (PaH) is the alkaloid constituent of Fibraurea tinctoria Lour. The present study aims to investigate the antitumor effect of photodynamic therapy (PDT) with PaH (PaH-PDT) on human OSCC cell lines both in vitro and in vivo. The results indicate that PaH-PDT exhibited a potent phototoxic effect in cell proliferation and produced cell apoptosis. PaH-PDT increased the percentage of cells in the G0/G1 phase and decreased the CDK2 and Cyclin E1 protein level. In addition, PaH-PDT markedly increased the generation of intracellular ROS, which can be suppressed using the ROS scavenger N-acetylcysteine (NAC). Furthermore, PaH-PDT increased the expression of p53 protein in vitro and in vivo. In vivo experiments revealed that the PaH-PDT resulted in an effective inhibition of tumor growth and prolonged the survival time of tumor-bearing mice. Moreover, no obvious signs of side effects or a drop in body weight was observed. These results suggested that PaH was a promising sensitizer that can be combined with light to produce significant anti-tumor effects in oral squamous cell carcinoma via enhanced ROS production and up-regulated expression of p53.

Paclitaxel is one of the most commonly used drugs for the treatment of nonsmall cell lung cancer (NSCLC). However acquired resistance to paclitaxel, epithelial to mesenchymal transition and cancer stem cell formation are the major obstacles for successful chemotherapy with this drug. Some of the major reasons behind chemoresistance development include increased ability of the cancer cells to survive under stress conditions by autophagy, increased expression of drug efflux pumps, tubulin mutations etc. In this study we found that inhibition of autophagy with chloroquine prevented development of paclitaxel resistance in A549 cells with time and potentiated the effect of paclitaxel by increased accumulation of superoxide-producing damaged mitochondria, with elevated ROS generation, it also increased the apoptotic rate and sub G0/ G1 phase arrest with time in A549 cells treated with paclitaxel and attenuated the metastatic potential and cancer stem cell population of the paclitaxel-resistant cells by ROS mediated modulation of the Wnt/β-catenin signaling pathway, thereby increasing paclitaxel sensitivity. ROS here played a crucial role in modulating Akt activity when autophagy process was hindered by chloroquine, excessive ROS accumulation in the cell inhibited Akt activity. In addition, chloroquine pre-treatment followed by taxol (10 nM) treatment did not show significant toxicity towards non-carcinomas WI38 cells (lung fibroblast cells). Thus autophagy inhibition by CQ pre-treatment can be used as a fruitful strategy to combat the phenomenon of paclitaxel resistance development as well as metastasis in lung cancer.