Cycle Phase Arrest Research Articles

A peptide alleviated oxidative damages in the L02 cells and mice liver

The liver is vitally metabolic for a multitude of biochemical reactions. Consequently, it generates many free radicals and reactive oxygen species, rendering it more susceptible to oxidative stress-induced damage. Oxidative stress represents a pivotal factor in the pathogenesis of liver diseases. We screened some antioxidant peptides previously. Here we investigated whether the peptides could attenuate oxidative damage with APPH in L02 cells. The results showed that one of the peptides, sequence FETLMPLWGNK, could decrease the excessive reactive oxygen species, increase antioxidant enzyme activity and protect mitochondrial function, reduce the ratio of apoptosis and S phase cycle arrest, and improve the survival rate of L02 cells damaged by APPH compared to cells of the control group. Then the peptide was evaluated in mice that CCl4 injured. We found that CCl4-injured mice had significantly increased serum inflammatory factors and liver injury markers, a large number of inflammatory cell infiltration, and local necrosis in the liver. The peptide could reduce inflammation, and improve liver pathological changes. This phenomenon may be associated with the activation of the Nrf2 signaling pathway. Concurrently, the peptide protects the liver by regulating the expression of proteins related to the mitochondrial apoptosis pathway (p53, Bax, Bcl-2, and Caspase3) and mitophagy-related proteins (PINK1, Parkin, and AMPKα). Therefore, the results indicated that the peptide is an active substance with antioxidant activity and anti-inflammatory effects.

Cucurbitacin B Inhibits the Proliferation of WPMY-1 Cells and HPRF Cells via the p53/MDM2 Axis.

Modern research has shown that Cucurbitacin B (Cu B) possesses various biological activities such as liver protection, anti-inflammatory, and anti-tumor effects. However, the majority of research has primarily concentrated on its hepatoprotective effects, with limited attention devoted to exploring its potential impact on the prostate. Our research indicates that Cu B effectively inhibits the proliferation of human prostate stromal cells (WPMY-1) and fibroblasts (HPRF), while triggering apoptosis in prostate cells. When treated with 100 nM Cu B, the apoptosis rates of WPMY-1 and HPRF cells reached 51.73 ± 5.38% and 26.83 ± 0.40%, respectively. In addition, the cell cycle assay showed that Cu B had a G2/M phase cycle arrest effect on WPMY-1 cells. Based on RNA-sequencing analysis, Cu B might inhibit prostate cell proliferation via the p53 signaling pathway. Subsequently, the related gene and protein expression levels were measured using quantitative real-time PCR (RT-qPCR), immunocytochemistry (ICC), and enzyme-linked immunosorbent assays (ELISA). Our results mirrored the regulation of tumor protein p53 (TP53), mouse double minute-2 (MDM2), cyclin D1 (CCND1), and thrombospondin 1 (THBS1) in Cu B-induced prostate cell apoptosis. Altogether, Cu B may inhibit prostate cell proliferation and correlate to the modulation of the p53/MDM2 signaling cascade.

Protective Mechanisms of Various Active Substances on Cell DNA Damage and Apoptosis Induced by Deoxynivalenol.

Deoxynivalenol (DON) is a secondary metabolite of fungi that is harmful to humans and animals. This study examined the protective effects of natural substances, including resveratrol, quercetin, vitamin E, vitamin C, and microbe-derived antioxidants (MA), on both human gastric mucosal cells (GES-1) and pig small intestinal epithelial cells (IPEC-1) when induced by DON. Cells were incubated with active substances for 3 h and then exposed to DON for 24 h. The oxidative stress index, cell cycle, and apoptosis were measured. As compared to cells treated only with DON, pretreatment with active substances improved the balance of the redox status in cells caused by DON. Specifically, quercetin, vitamin E, vitamin C, and MA showed the potential to alleviate the G2 phase cell cycle arrest effect that was induced by DON in both kinds of cells. It was observed that vitamin E and vitamin C can alleviate DON-induced apoptosis and the G2 phase cycle arrest effect mediated via the ATM-Chk 2-Cdc 25C and ATM-P53 signaling pathways in GES-1 cells. In IPEC-1 cells, vitamin C and MA can alleviate both DON-induced apoptosis and the G2 phase cycle arrest effect via the ATM-Chk 2-Cdc 25C signaling pathway. Different bioactive substances utilize different protective mechanisms against DON in interacting with different cells. The proper addition of vitamin E and vitamin C to food can neutralize the toxic effect of DON, while the addition of vitamin C and MA to animal feed can reduce the harm DON does to animals.

LRP8 promotes tumorigenesis in ovarian cancer through inhibiting p53 signaling.

Ovarian cancer (OC) is the most lethal gynecological malignancy with a high mortality rate. Low-density lipoprotein (LDL) receptor-related protein 8 (LRP8) is a cell membrane receptor belonging LDL receptor family and is involved in several tumor progressions. However, there is limited understanding of how LRP8 mediates OC development. LRP8 expression level was identified in human OC tissues and cells using immunohistochemical staining and quantitative polymerase chain reaction assays, respectively. Functions of LRP8 in OC progression were evaluated by Celigo cell counting, wound healing, transwell and flow cytometry assays, and the xenograft models. The human phospho-kinase array analysis was used for screening potential signaling involved in OC development. We observed that LRP8 was overexpressed in OC tissues, and high expression of LRP8 was associated with poor prognosis of OC patients. Functionally, LRP8 knockdown remarkably reduced proliferation and migration of OC cells, and induced apoptosis and S phase cycle arrest. LRP8 deficiency attenuated in vivo tumor growth of OC cells. Moreover, the addition of p53 inhibitor partially reversed the effects of LRP8 knockdown on OC cell proliferation and apoptosis, indicating the involvement of p53 signaling in LRP8-mediated OC progression. This study confirmed that LRP8/p53 axis contributed to OC progression, which might serve as a novel potential therapeutic target for OC patients.

Transcriptomics and molecular docking reveal the potential mechanism of lycorine against pancreatic cancer.

Pancreatic cancer is an extremely malignant digestive tumor, however, owing to its high drug resistance of pancreatic cancer, the search for more effective anti-pancreatic cancer drugs is urgently needed. Lycorine, an alkaloid of natural plant origin, exerts antitumor effects on a variety of tumors. This study aimed to investigate the therapeutic effect of lycorine on pancreatic cancer and elucidate its potential molecular mechanism. Two pancreatic cancer cell lines, PANC-1 and BxPC-3, were used to investigate the therapeutic effects of lycorine on pancreatic cancer in vitro using the CCK8 assay, colony formation assay, 5-Ethynyl-2'- deoxyuridine (EdU) incorporation assay, flow cytometry, and western blotting. Transcriptome sequencing and gene set enrichment analysis (GSEA) were used to analyze the differentially expressed genes and pathways after lycorine treatment. Molecular docking, quantitative real-time PCR (qRT-PCR), oil red O staining, small interfering RNA (siRNA) transfection, and other experiments were performed to further validate the differentially expressed genes and pathways. In vivo experiments were conducted to investigate lycorine's inhibitory effects and toxicity on pancreatic cancer using a tumor-bearing mouse model. Lycorine inhibited the proliferation of pancreatic cancer cells, caused G2/M phase cycle arrest and induced apoptosis. Transcriptome sequencing and GSEA showed that lycorine inhibition of pancreatic cancer was associated with fatty acid metabolism, and aldehyde dehydrogenase 3A1 (ALDH3A1) was a significantly enriched target in the fatty acid metabolism process. ALDH3A1 expression was significantly upregulated in pancreatic cancer and was closely associated with prognosis. Molecular docking showed that lycorine binds strongly to ALDH3A1. Further studies revealed that lycorine inhibited the fatty acid oxidation (FAO) process in pancreatic cancer cells and induced cell growth inhibition and apoptosis through ALDH3A1. Lycorine also showed significant suppressive effects in tumor-bearing mice. Importantly, it did not result in significant toxicity to liver and kidney of mice, demonstrating its therapeutic potential as a safe antitumor agent. Lycorine inhibited pancreatic cancer cell proliferation, blocked the cell cycle, and induced apoptosis by targeting ALDH3A1. FAO inhibition was identified for the first time as a possible mechanism for the anticancer effects of lycorine. These findings enrich the theory of targeted therapy for pancreatic cancer, expand our understanding of the pharmacological targets of lycorine, and provide a reference for exploring its natural components.

The Correlation of Centromere Protein Q with Diagnosis and Prognosis in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the major types of liver cancer. Previous studies have shown that the centromere protein family is associated with malignant biological behaviors such as HCC proliferation. As a member of the centromere protein family, centromere protein Q (CENPQ) is closely associated with immunotherapy and immune cell infiltration in various tumors. However, the role and mechanism of CENPQ in HCC remain unclear. Multiple public databases and RT-qPCR were used to study the expression of CENPQ in HCC. Based on TCGA data, the correlation between CENPQ and clinicopathological characteristics and prognosis of HCC patients was analyzed, and its diagnostic value was evaluated. The potential biological functions of CENPQ in HCC were explored by functional enrichment analysis of differentially expressed genes. The distribution of tumor-infiltrating immune cell types was assessed using single-sample GSEA, and immune checkpoint gene expression was analyzed using Spearman correlation. Subsequently, loss-of-function experiments were performed to determine the function of CENPQ on the cell cycle and proliferation of HCC cells in vitro. CENPQ was found highly expressed in HCC and correlated with weight, BMI, age, AFP, T stage, pathologic stage, histologic grade, and prothrombin time (all p < 0.05). ROC and Kaplan-Meier analyses indicated that CENPQ may be potentially used as a diagnostic marker for HCC (AUC = 0.881), and its upregulation is associated with decreased OS (p = 0.002), DSS (p < 0.001), and PFI (p = 0.002). Functional enrichment analysis revealed an association of CENPQ with biological processes such as immune cell infiltration, cell cycle, and hippo-merlin signaling deregulation in HCC. Furthermore, knockdown of CENPQ manifested in HCC cells with G0/1 phase cycle arrest and decreased proliferative capacity. CENPQ expression was higher in HCC tissues than in normal liver tissues. It was significantly associated with poor prognosis, immune cell infiltration, cell cycle, and proliferation. Therefore, CENPQ may become a promising prognostic biomarker for HCC patients.

DON induced DNA damage triggers absence of p53-mediated G2 arrest and apoptosis in IPEC-1 cells

Deoxynivalenol (DON) stands among the prevalent mycotoxins, and usually contaminates cereal foods and animal feed, leading to human and animal clinical poisoning symptoms such as abdominal pain, diarrhea, and vomiting. To date, the mechanism of toxicity of DON in different mammalian cells is not fully elucidated. In this study, we explored the detrimental impacts of DON on porcine intestinal epithelial cells (IPEC-1), serving as a representative model for porcine intestinal epithelial cells. After treating cells with DON for 24 h, DON can significantly inhibit the activity of cells, induce the production of reactive oxygen species (ROS), significantly reduce the content of glutathione and the activity of catalase, and increase the activity of superoxide dismutase and malondialdehyde, leading to an imbalance in intracellular redox status. In addition, DON can induce DNA double-strand breaks, and decrease mitochondrial membrane potential. Furthermore, DON can promote the release of Cyt C through changes in mitochondrial permeability through inhibit the expression of B-cell lymphoma 2 (Bcl-2) proteins, leading to apoptosis through the mitochondrial pathway. On the other hand, we found that DON can cause IPEC-1 cells G2 phase cycle arrest. Different with our pervious study, DON induces cell cycle arrest in the G2 phase only by activating the ATM-Chk2-Cdc 25 C pathway, but cannot regulate the cell cycle arrest via the ATM-p53 pathway. These results indicate that DON can induce the same toxic phenotype in different cells, but its toxic mechanism is different. All these provide a rationale for revealing DON induced cytotoxicity and intestinal diseases.

Arctigenin Suppresses the Proliferation and Metastasis, and Induces Apoptosis and Cycle Arrest of Osteosarcoma Cells by inhibiting HMOX1 Expression.

Osteosarcoma is the most common malignant bone tumor, with highly proliferative and metastatic properties. Previous studies have reported that arctigenin (Arc), a bioactive lignin compound, showed excellent anti-tumor activities in a variety of human cancers. However, its role in osteosarcoma has not been studied. We aimed to investigate the anti-tumor effects of Arc on osteosarcoma cell proliferation, migration, invasion, apoptosis, and cell cycle. Effects of Arc on osteosarcoma cell proliferation were detected by MTT and colony formation assay. Flow cytometry analysis was performed to assess the cell apoptosis and cycle arrest. Transwell assay was used to evaluate the capability of migration and invasion. qRT-PCR and Western blot were employed to determine the changes in mRNA and protein levels. Arc could significantly suppress the proliferation, colony formation, and induce cell apoptosis and S phase cycle arrest of MG63 and U-2 OS cells in a dose-dependent manner. In addition, we also observed an inhibitory effect of Arc treatment on osteosarcoma cell invasion, migration, and epithelial-mesenchymal transition (EMT). HMOX1, encoding enzyme heme oxygenase-1, was predicted to be a candidate target of Arc using STITCH. Arc treatment significantly reduced the mRNA and protein levels of HMOX1. Furthermore, overexpression of HMOX1 could partly reverse the inhibitory effects of Arc on osteosarcoma cell malignant phenotypes. Our results suggest that Arc inhibits the proliferation, metastasis and promotes cell apoptosis and cycle arrest of osteosarcoma cells by downregulating HMOX1 expression.

Combining transcriptomics and network pharmacology to reveal the mechanism of Zuojin capsule improving spasmolytic polypeptide-expressing metaplasia

Ethnopharmacological relevanceSpasmolytic polypeptide-expressing metaplasia (SPEM) is a gastric precancerous lesion (GPL). Zuojin capsule (ZJC), consisting of Coptis chinensis Franch. (Ranunculaceae, recorded in the Chinese Pharmacopoeia as Rhizoma Coptidis) and Tetradium ruticarpum (A.Juss.) T.G.Hartley (Rutaceae, recorded in the Chinese Pharmacopoeia as Fructus Evodiae), has long been used for various gastrointestinal diseases. However, the effect and mechanism of ZJC on SPEM remain unclear. Aim of the studyTo clarify the role of ZJC in improving SPEM and study its mechanism. Materials and methodsThe study utilized SPEM mice induced by 250 mg/kg body weight of tamoxifen (TAM) to assess the effects of ZJC and investigate its possible mechanisms. A strategy of transcriptomics combined with network pharmacology was conducted to explore the targets and mechanisms of ZJC in improving SPEM. The “ingredients-target-pathway” network was constructed, and the possible connections were verified by RT-qPCR and Western blot assays. ResultsZJC significantly attenuated the abnormal serological indices, destruction of the gastric mucosal structure, hyperplasia of gastric pits, increased gastric mucus, massive secretion of CD44 and TFF2, oxyntic atrophy and massive proliferation of stem/progenitor cells in TAM-induced SPEM mice. Combined transcriptomics and network pharmacology analysis, 50 core targets of ZJC related to SPEM improvement were obtained. KEGG results showed that the core targets were significantly enriched in the cell cycle, and PI3K-AKT signaling pathway. The top-ranked targets according to PPI network analysis were CDK1, CCNB1, and CCNA2, which are also associated with cell cycle. Combined experiments demonstrated that ZJC can induce G2/M phase cycle arrest and inhibit TAM-induced malignant proliferation by regulating abnormal activation of cell cycle-related proteins such as CDK1, CCNB1, CCNA2 and PI3K-AKT signaling pathways. ConclusionsZJC may improve TAM-induced SPEM by inhibiting abnormal activation of cell cycle-related proteins (CDK1, CCNB1, CCNA2) and PI3K-AKT signaling pathway. This finding supports the use of ZJC, a famous traditional Chinese medicine compound, as a potential treatment for gastric precancerous lesions.

Two novel silver(I) phenanthroline derivative complexes induce G2/M phase cycle arrest and apoptosis of MDA‐MB‐231 cancer cells by multiple mechanisms

Two novel silver(I) phenanthroline derivative complexes (P‐235 and P‐239) have been synthesized and characterized by IR, HPLC‐MS, and 1HNMR. The cytotoxicity of two complexes exhibited significant cytotoxicity against human breast cancer (MDA‐MB‐231) cell line (IC50 = 0.48 ± 0.01 and 0.12 ± 0.01 μM) and less toxicity than cisplatin by MTT assays. Furthermore, anticancer mechanistic studies showed that P‐235 and P‐239 induced G2/M phase cell cycle arrest to inhibit the growth of MDA‐MB‐231 cells. Flow cytometry analysis showed that MDA‐MB‐231 cells could be significantly induced to undergo apoptosis by P‐235 and P‐239. And P‐235‐ and P‐239‐induced apoptosis was linked with reactive oxygen species (ROS) production. Further study revealed that P‐235 and P‐239 cause mitochondrial membrane potential depolarization and destroy mitochondrial membrane potential.

Molecular mechanism of Ganji Fang in the treatment of hepatocellular carcinoma based on network pharmacology, molecular docking and experimental verification technology.

Background: Hepatocellular carcinoma (HCC) is a malignant tumor harmful to human health. Ganji Fang (GJF) has good clinical efficacy in the treatment of HCC, but its mechanism is still unclear. Objective: The aim of this study was to investigate the mechanism of action of GJF in the treatment of HCC through network pharmacology, molecular docking and in vitro experiments. Methods: A series of network pharmacology methods were used to identify the potential targets and key pathways of GJF in the treatment of HCC. Then, molecular docking technology was used to explore the binding ability of key active ingredients and targets in GJF. Multiple external databases were used to validate the key targets. In in vitro experiments, we performed MTT assays, wound-healing assays, cell cycle assays, apoptosis assays and RT‒qPCR to verify the inhibitory effect of GJF on the Human hepatoma G2 (HepG2) cells. Result: A total of 162 bioactive components and 826 protein targets of GJF were screened, and 611 potential targets of HCC were identified. Finally, 63 possible targets of GJF acting on HCC were obtained. KEGG enrichment analyses showed that the top five pathways were the cell cycle, cellular senescence, p53 signaling pathway, PI3K/Akt signaling pathway, and progesterone-mediated oocyte maturation. Among them, we verified the PI3K/Akt signaling pathway. CCNE1, PKN1, CCND2, CDK4, EPHA2, FGFR3, CDK6, CDK2 and HSP90AAI were enriched in the PI3K/Akt pathway. The molecular docking results showed that the docking scores of eight active components of GJF with the two targets were all less than -5.0, indicating that they had certain binding activity. In vitro cell experiments showed that GJF could inhibit the proliferation and migration of HepG2 cells, block the cell cycle and induce apoptosis of HepG2 cells, which may be related to the PI3K/Akt signaling pathway. In summary, EPHA2 may be an important target of GJF in HCC, and pachymic acid may be an important critical active compound of GJF that exerts anticancer activity. Conclusion: In general, we demonstrated, for the first time, that the molecular mechanism of GJF in HCC may involve induction of G0/G1 phase cycle arrest through inhibition of the PI3K/Akt signaling pathway and promote apoptosis of hepatoma cell lines. This study provides a scientific basis for the subsequent clinical application of GJF and the in-depth study of its mechanism.

Anthocyanins from Lycium ruthenicum Murray Inhibit HepG2 Cells Growth, Metastasis and Promote Apoptosis and G2/M Phase Cycle Arrest by Activating the AMPK/mTOR Autophagy Pathway.

Among the most common malignancies in humans, liver cancer ranks third in terms of mortality in the world. Seeking new anticancer drugs or adjuvant chemotherapy drugs from natural products has attracted the attention of many researchers. Lycium ruthenicum Murray (LR), a health food and traditional Chinese medicine, exerts extensive pharmacological properties, of which anthocyanins are one of the key active components. In this research, we explored the antitumor activity and autophagy regulation mechanism of anthocyanins from Lycium ruthenicum Murray (ALR) in HepG2 cells. Our results found that ALR profoundly reduced the cell viability, clone formation, migration, and invasion and promoted apoptosis and G2/M phase arrest of HepG2 cells in a dose-dependent pattern. Further studies confirmed that ALR treatment significantly increased the number of autophagic vacuoles and autophagosomes, upregulated the expression of Beclin-1, p62, LC3-II/LC3-I, and p-AMPK, and concomitantly downregulated the expression of p-mTOR. When autophagy was inhibited by 3-methyladenine (3-MA), ALR-induced proliferation inhibition, invasion, and migration capabilities, as well as apoptosis rate and G2/M phase arrest, were all reversed, and the activities of key proteins in the AMPK/mTOR pathway were all constrained. In summary, the results presented here indicate that ALR may be effective as a natural antitumor agent by activating AMPK and inhibiting the mTOR autophagy pathway in HepG2 cells.

MiR-338-3p acts as a tumor suppressor in lung squamous cell carcinoma by targeting FGFR2/FRS2

BackgroundLung cancer refers to the occurrence of malignant tumors in the lung, and squamous cell carcinoma is one of the most common pathological types of non-small cell lung cancer. Studies have shown that microRNAs (miRNAs) play an important role in the occurrence, development, early diagnosis, and treatment of lung cancer. This study aimed to explore the role and possible mechanism of MicroRNA-338-3p (miR-338-3p) in lung squamous cell carcinoma (LUSC). MethodIn this study, we compared 238 LUSC patients with relatively high miR-338-3p expression levels with 238 miR-338-3p expression levels in The Cancer Genome Atlas (TCGA)-LUSC dataset using first-line gene set enrichment analysis (GSEA). Second, the mRNA expression of miR-338-3p, FGFR2, and fibroblast growth factor receptor substrate 2 (FRS2) in 30 lung cancers and adjacent lung tissues was detected using quantitative real-time polymerase chain reaction (qRT-PCR). Finally, in vitro experiments were conducted, whereby the expression levels of miR-338-3p in lung cancer cells (H1703, SKMES1, H2170, H520) and normal lung epithelial cells (16HBE) were detected using qRT-PCR. miR-338-3p was overexpressed in lung cancer cells (H1703), and the cell proliferation (cell counting kit-8 [CCK8] assay), colony formation, cell apoptosis, cell cycle (BD-FACSVerse assay, Becton Dickinson, Bedford, MA, USA), cell invasion, and migration (Transwell assay, Thermo Fischer Corporation, Waltham, MA, USA) were detected. ResultsWe found that the expression of miR-338-3p was significantly reduced in LUSC tissues (p ​< ​0.001) and cancer cell lines (P < 0.01), and miR-338-3p was significantly negatively correlated with the expression of FGFR2 (P < 0.001) and FRS2 (P < 0.01). Furthermore, overexpression of miR-338-3p inhibited proliferation (P < 0.001), migration, and invasion (P < 0.001) of LUSC cell lines and increased apoptosis in the G1 phase (P < 0.001) and cell cycle arrest (P < 0.05). ConclusionsOur study demonstrates that miR-338-3p inhibits tumor cell proliferation and migration by targeting FGFR2 and FRS2 in LUSC. We believe that miR-338-3p may be a promising target for the treatment of LUSC.

The antitumor activity of a novel GCN2 inhibitor in head and neck squamous cell carcinoma cell lines

BackgroundGeneral control nonderepressible 2 (GCN2) senses amino acid deprivation and activates activating transcription factor 4 (ATF4), which regulates many adaptive genes. We evaluated the impact of AST-0513, a novel GCN2 inhibitor, on the GCN2-ATF4 pathway. Additionally, we evaluated the antitumor effects of AST-0513 in amino acid deprivation in head and neck squamous cell carcinoma (HNSCC) cell lines. MethodsGCN2 expression in HNSCC patient tissues was measured by immunohistochemistry. Five HNSCC cell lines (SNU-1041, SNU-1066, SNU-1076, Detroit-562, FaDu) grown under amino acid deprivation conditions, were treated with AST-0513. After AST-0513 treatment, cell proliferation was measured by CCK-8 assay. Flow cytometry was used to evaluate apoptosis and cell cycle phase. In addition, immunoblotting was performed to evaluate the effect of AST-0513 on the GCN2-ATF4 pathway, cell cycle arrest, and apoptosis. ResultsWe demonstrated that GCN2 was highly expressed in HNSCC patient tissues. AST-0513 inhibited the GCN2-ATF4 pathway in all five HNSCC cell lines. Inhibiting the GCN2-ATF4 pathway during amino acid deprivation reduced HNSCC cell proliferation and prevented adaptation to nutrient stress. Moreover, AST-0513 treatment led to p21 and Cyclin B1 accumulation and G2/M phase cycle arrest. Also, apoptosis was increased, consistent with increased bax expression, increased bcl-xL phosphorylation, and decreased bcl-2 expression. ConclusionA novel GCN2 inhibitor, AST-0513, inhibited the GCN2-ATF4 pathway and has antitumor activity that inhibits proliferation and promotes cell cycle arrest and apoptosis. Considering the high expression of GCN2 in HNSCC patients, these results suggest the potential role of GCN2 inhibitor for the treatment of HNSCC.

Discovery of novel VEGFR-2-PROTAC degraders based on the localization of lysine residues via recruiting VHL for the treatment of gastric cancer

VEGFR-2 is an attractive therapeutic target for antitumor drug research by blocking tumor angiogenesis and PROTAC provides a new technology for targeted protein knockout. Herein, a library of novel VEGFR-2-PROTAC degraders were rationally designed and synthesized based on the Lys residue region on the surface of VEGFR-2 protein using protein structure-based drug design strategy. Among them, P7 exhibited preferable antitumor activity against HGC-27 cells and less toxic to human normal HUVEC, HEK293T and GES-1 cells in vitro, as well as the potent degradation activity of VEGFR-2 protein in HGC-27 cells (DC50: 0.084 ± 0.04 μM, Dmax: 73.7%) and HUVEC cells (DC50: 0.51 ± 0.10 μM, Dmax: 76.6%). Additionally, P7 degraded VEGFR-2 protein by the formation of ternary complex and the ubiquitin proteasome pathway in HGC-27 cells. Furthermore, P7 shortened the half-life of VEGFR-2 protein synthesis and had no inhibitory effect on the expression of VEGFR-2 mRNA in HGC-27 cells. Moreover, P7 inhibited the colony formation, migration and invasion of HGC-27 cells in a time- and dose-dependent manner, and meanwhile induced G2/M phase cycle arrest and apoptosis. All the results demonstrated that P7 could be as a promising VEGFR-2-PROTAC degrader for gastric cancer therapy.

The Mechanism of Rac1 in Regulating HCC Cell Glycolysis Which Provides Underlying Therapeutic Target for HCC Therapy.

Aim To explore the role of Rac1 on sorafenib resistance in hepatocellular carcinoma. Methods CCK-8, wound healing assay, Transwell, and cell cycle assay were used to detect the tumor cells development. Cell viability was assessed by MTT. The glycolytic pathway was revealed by cellular metabolism assays. Result We recovered that Rac1 upregulation was related to HCC patients' poorer prognosis. Forced expression of Rac1 promoted cell development and sorafenib chemoresistance in HCC cells. Rac1 inhibitor EHop-016 and sorafenib combination markedly prevented cell viability, G2/M phase cycle arrest, and apoptosis than single therapy. Furthermore, combination therapy decreased glycolysis in HCC cells. In vivo, the tumor growth was significantly prevented by combination therapy single therapy. Conclusion Our research declares that Rac1 inhibition could block sorafenib resistance in HCC by decreasing glycolysis, which would provide an underlying target for HCC therapy.

Inhibition of cell proliferation by Tas of foamy viruses through cell cycle arrest or apoptosis underlines the different mechanisms of virus–host interactions

ABSTRACT Foamy viruses belong to the Spumaretrovirinae subfamily member of the Retroviridae family and produce nonpathogenic infection to hosts in the natural conditions. However, infections of foamy viruses can dramatically cause severe cytopathic effects in vitro. To date, the exact molecular mechanism has remained unclear which implied the tremendous importance of virus-host cell immune reactions. In this study, we found that the transactivator Tas in two foamy viruses isolated from Old World Monkey (OWM) induced obvious inhibition of cell proliferation via the upregulation of Foxo3a expression. It was mediated by the generation of ROS and the initiation of ER stress, and ultimately, the mitochondrial apoptosis pathway was triggered. Notably, PFV Tas contributed to the accumulation of G0/G1 phase cycle arrest induced by the activation of the p53 signaling pathway and the nuclear transportation of HDAC4 via upregulating PPM1E expression. Together, these results demonstrated the different survival strategies by which foamy virus can hijack host cell cytokines and regulate virus-host cell interactions.

Characterization of novel heterocyclic compounds based on 4-aryl-4H-chromene scaffold as anticancer agents: Design, synthesis, antiprofilerative activity against resistant cancer cells, dual β-tubulin/c-Src inhibition, cell cycle arrest and apoptosis induction

In this study, three novel sets of 4-aryl-4H-chromene derivatives 4a–c, 6a–d and 7a–c were synthesized and evaluated for anticancer activity. Characterization of new compounds was established on basis of elemental analyses and spectral data. All new compounds were investigated for their antiproliferative activity against HCT-116, HepG-2 and MCF-7 cell lines using vinblastine and staurosporine as positive controls. Compounds 4b, 4c and 6d showed superior cytotoxicity against HCT-116, HepG-2 and MCF-7 cell lines, respectively with IC50 ranged from 3.31 to 4.95 μM. Additionally, compound 4b showed excellent cytotoxic activity (IC50 = 39.83 μM) against resistant HCT-116 better than doxorubicin (IC50 = 164.60 μM), while compounds 4c and 6d exhibited moderate cytotoxic activity against resistant HepG-2 and resistant MCF-7 cell lines. The most potent compounds inhibited both β-tubulin polymerization (IC50 = 8.78 – 16.47 μM) and c-Src kinase (IC50 = 0.07 – 0.18 μM) enzymes. Compounds 4b, 4c and 6d activated caspase-3, caspase-7, and caspase-9 proteins relative to untreated cells, revealing apoptosis induction. Apoptosis was also confirmed through up-regulation of Bax and down-regulation of Bcl-2 protein expression levels. Cell cycle analysis of compound 6d showed accumulation of cells in pre-G1 phase and cell cycle arrest at S phase in MCF-7 treated cells. As well 6d caused 7- and 63- fold increase in apoptotic cell population at early and late apoptosis stages. Finally, molecular modeling study was performed to predict the binding pattern of the target compounds inside c-Src kinase receptor.

Spirostane saponins with a rearranged A/B ring system isolated from the rhizomes of Ophiopogon japonicus

In this study, the popular food and medicinal herb Ophiopogon japonicus was investigated alongside a 70% ethanol extract of its rhizomes, revealing twenty-three steroidal glycosides with four undescribed steroidal saponins, named ophiopogonols A–D. Among them, ophiopogonols A–B are two unusual spirostanols with a rearranged A/B ring system (5/7/6/5/5/6 ring system) that have not previously been identified in plants. The chemical structures of all isolated steroidal glycosides were elucidated by comprehensive analysis through chemical methods, HRESIMS, and NMR spectroscopy. Further, putative biosynthetic pathways for ophiopogonols A–B were proposed. In addition, based on traditional applications of O. japonicus, cytotoxic effects of the isolates were evaluated using human large cell lung carcinoma cells (NCI–H460 cells). Sprengerinin C displayed a remarkable cytotoxic effect with IC50 values of 2.1 ± 0.8 μM by inducing apoptosis and G2/M phase cycle arrest in the NCI–H460 cell line.

Licorice extract inhibits growth of non-small cell lung cancer by down-regulating CDK4-Cyclin D1 complex and increasing CD8+ T cell infiltration

BackgroundTargeting tumor microenvironment (TME) may provide therapeutic activity and selectivity in treating cancers. Therefore, an improved understanding of the mechanism by which drug targeting TME would enable more informed and effective treatment measures. Glycyrrhiza uralensis Fisch (GUF, licorice), a widely used herb medicine, has shown promising immunomodulatory activity and anti-tumor activity. However, the molecular mechanism of this biological activity has not been fully elaborated.MethodsHere, potential active compounds and specific targets of licorice that trigger the antitumor immunity were predicted with a systems pharmacology strategy. Flow cytometry technique was used to detect cell cycle profile and CD8+ T cell infiltration of licorice treatment. And anti-tumor activity of licorice was evaluated in the C57BL/6 mice.ResultsWe reported the G0/G1 growth phase cycle arrest of tumor cells induced by licorice is related to the down-regulation of CDK4-Cyclin D1 complex, which subsequently led to an increased protein abundance of PD-L1. Further, in vivo studies demonstrated that mitigating the outgrowth of NSCLC tumor induced by licorice was reliant on increased antigen presentation and improved CD8+ T cell infiltration.ConclusionsBriefly, our findings improved the understanding of the anti-tumor effects of licorice with the systems pharmacology strategy, thereby promoting the development of natural products in prevention or treatment of cancers.