Inhibited Cell Survival Research Articles

Ruta graveolens, but Not Rutin, Inhibits Survival, Migration, Invasion, and Vasculogenic Mimicry of Glioblastoma Cells.

Glioblastoma (GBM) is the most aggressive type of brain tumor, characterized by poor outcome and limited therapeutic options. During tumor progression, GBM may undergo the process of vasculogenic mimicry (VM), consisting of the formation of vascular-like structures which further promote tumor aggressiveness and malignancy. The resulting resistance to anti-angiogenetic therapies urges the identification of new compounds targeting VM. Extracts of natural plants may represent potential therapeutic tools. Among these, components of Ruta graveolens water extract (RGWE) display a wide range of biological activities. To test the effect of RGWE on human GBM and rat glioma cell line VM, tube formation on a gelled matrix was monitored. Quantitative assessment of VM formation shows the clear-cut inhibitory activity of RGWE. Unlike rutin, one of the most abundant extract components, the whole RGWE strongly reduced the migration and invasion of GBM tumor cells. Moreover, RGWE induced cell death of GBM patient-derived cancer stem cells and impaired VM at sub-lethal doses. Overall, our data reveal a marked RGWE-dependent inhibition of GBM cell survival, migration, invasion, and VM formation. Thus, the clear-cut ability of RGWE to counteract GBM malignancy deserves attention, holding the promise to bring natural products to clinical use, thus uncovering new therapeutic opportunities.

Gene Expression Profiling of Maslinic Acid-treated MCF-7 Breast Cancer Cells Using Nanostring nCounter Pancancer Pathway Panel

Breast cancer remains a significant global health concern, impacting millions of women every year. Maslinic acid (MA), a pentacyclic triterpene has been found to exert promising anticancer effect in various cancers, including breast cancer, yet the underlying mechanisms remain unclear. This study aims to elucidate the anticancer properties of MA via gene expression profiles in breast cancer cells. Cytotoxicity assay results revealed that MCF-7 exerts the highest sensitivity after 72 h of MA treatment followed by T-47D and MDA-MB-231. MCF-7 were then selected for in-depth analysis using the Nanostring nCounter Pancancer Pathway Panel to analyze the differential expression of genes (DEGs). Across three time points (24, 48, and 72 h), 20 significant DEGs were identified, of which 5 were upregulated and 15 were downregulated. In silico analysis indicated that these DEGs were involved in Pathway of Cancer, Focal Adhesion-PI3K-mTOR Signaling Pathway, PI3K-Akt, and Ras Signaling Pathway. The regulation of these DEGs contributes to several cellular activities such as apoptosis, inhibition of cell proliferation, cell cycle and survival, reduction of glycolysis, angiogenesis, and DNA repair. Additionally, the unfolded protein response emerged as a noteworthy biological process in this study. This study unravels the molecular mechanisms underpinning the therapeutic potential of MA against breast cancer.

Gochujang suppresses cell survival and changes reactive oxygen species metabolism in colorectal cancer cells.

There is a significant global increase in colorectal cancer (CRC) among young adults. Gochujang, one of the signature Korean traditional fermented foods, contains various bioactive compounds and has multiple health-beneficial effects, including anticancer effects; however, the detailed cellular and molecular mechanisms of its anticancer outcomes are not fully understood. The objective of the present study was to investigate the detailed underlying anticancer mechanisms of Gochujang in CRC cells. Gochujang was extracted with 80% ethanol, and total polyphenol contents (9.9 ± 1.63 mgGAE/g) and total flavonoid contents (0.14 ± 0.07 mgQE/g) of Gochujang extract (GE) were evaluated. GE significantly suppressed cell viability, migration, and colony formation in CRC cells. Also, GE increased the cell cycle arrest-related protein p21 level, whereas it decreased cell cycle progression-associated proteins, such as p-Rb. Moreover, GE markedly elevated the levels of proapoptotic proteins (e.g. Bim and c-PARP), while it downregulated antiapoptotic protein expressions (e.g. Bcl-2 and Bcl-xL). GE also altered the expression of the autophagy-involved proteins. Furthermore, GE strongly reduced the expression of major antioxidant enzymes and increased the reactive oxygen species (ROS) generation in CRC cells, causing an imbalance of ROS metabolism. In conclusion, this study demonstrated that Gochujang exerts anticancer effects in CRC cells by inhibiting cell proliferation, increasing cell death, and interrupting ROS metabolism.

From parasitic life to health-promoting applications - A versatile goldmine discovered in nature's secret treasure chest: Orobanche nana

Studies evaluating the phytoconstituents and therapeutic potential of species belonging to Orobanche (Family Orobanchaceae) are rather limited. The present study was designed to evaluate the chemical composition, antioxidant, enzyme inhibition and cytotoxic properties of the aerial parts of Orobanche nana Noë ex Rchb. Extracts were prepared by sequential maceration in dichloromethane, ethyl acetate and ethanol and finally an aqueous extraction by infusion were performed. NMR and LC-DAD-MS analysis allowed the identification of different phytoconstituents including the characteristic compounds of Orobanche like verbascoside, poliumoside, orobanone and orobanchoside. The ethanol extract displayed the highest total phenolic (115.63 mg GAE/g) and flavonoids (16.53 mg RE/g) contents, antiradical (DPPH = 623.70 mg TE/g; ATBS = 843.50 mg TE/g) and ions reducing (Cu++ = 725.39; Fe+++ = 617.70) properties while the aqueous extract exerted the best chelating power (19.54 mg EDTAE/g). It was determined that EtOH and Water extracts applied to HepG2 cells decreased the levels of anti-apoptotic proteins p-NFκB, BCL-2 and BCL-XL, while increasing the levels of apoptotic proteins BAX and p-53, thus inhibiting cell survival. In addition, Orobanche nana played an active role in the rearrangement of overexpress MMPs that cause disruption of ECM homeostasis. We employed Network Pharmacology to investigate the mechanisms through which Orobanche nana's compounds impact Kidney and Liver diseases. These findings suggested that O. nana could be a promising source of bioactive molecules with potential therapeutic applications.

Therapeutic potential of monoterpene molecules acts against 7KCh-mediated oxidative stress and neuroinflammatory amyloidogenic signalling pathways

Alzheimer’s disease (AD) is a degenerative disorder characterised by amyloid-beta aggregates activated by the accumulation of lipid molecules and their derivatives, especially 7-ketocholesterol (7KCh), an oxidised lipid that plays a great part in the progression of AD. The current therapeutics need bio-potential molecules and their biomedical application preventing 7KCh-induced cytotoxicity. In this study, bornyl acetate (BA) and menthol (ME), the natural monoterpenes were investigated for their neuroprotective effects against 7KCh-induced SH-SY5Y cells and their effects were compared to the standard drug galantamine (GA). 7KCh-induced changes like lipid accumulation, amyloid generation, free radical generation, acetylcholinesterase levels, calcium accumulation and mitochondrial membrane integrity were analysed in SH-SY5Y cells with or without BA and ME treatment. Furthermore, various mediators involved in the amyloidogenic, inflammatory and apoptotic pathways were studied. In our results, the cells induced with 7KCh upon co-treatment with BA and ME significantly reduced lipid accumulation and amyloid generation through toll-like receptor (TLR) 4 suppression and enhanced ATP binding cassette (ABCA) 1-mediated clearance. Co-treatment with BA and ME concurrently regulated oxidative stress, acetylcholinesterase activity, mitochondrial membrane potential and intracellular calcification altered by 7KCh-induced SH-SY5Y cells. Moreover, 7KCh-induced cells showed elevated mRNA levels of misfolded protein markers and apoptotic mediators which were significantly downregulated by BA and ME co-treatment. In addition, the protein expression of amyloidogenic, proinflammatory as well as pro-apoptotic markers was decreased by BA and ME co-treatment in 7KCh-induced cells. Overall, BA and ME mediated inhibition of amyloidogenic activation and cell survival against 7KCh-induced inflammation, thereby preventing the onset and progression of AD in comparison to GA.

GenoMine: a CRISPR-Cas9-based kill switch for biocontainment of Pseudomonas putida.

Synthetic genetic circuits have revolutionised our capacity to control cell viability by conferring microorganisms with programmable functionalities to limit survival to specific environmental conditions. Here, we present the GenoMine safeguard, a CRISPR-Cas9-based kill switch for the biotechnological workhorse Pseudomonas putida that employs repetitive genomic elements as cleavage targets to unleash a highly genotoxic response. To regulate the system's activation, we tested various circuit-based mechanisms including the digitalised version of an inducible expression system that operates at the transcriptional level and different options of post-transcriptional riboregulators. All of them were applied not only to directly control Cas9 and its lethal effects, but also to modulate the expression of two of its inhibitors: the AcrIIA4 anti-CRISPR protein and the transcriptional repressor TetR. Either upon direct induction of the endonuclease or under non-induced conditions of its inhibitors, the presence of Cas9 suppressed cell survival which could be exploited beyond biocontainment in situations where further CRISPR genome editing is undesirable.

Anti-Skin Aging and Cytotoxic Effects of Methanol-Extracted Solanum betaceum Red Fruit Seed Extract on Ca9-22 Gingival Carcinoma Cells.

The tamarillo, or Solanum betaceum, recognized for its comprehensive nutritional profile, has long been valued for its diverse ethnobotanical uses. This study delves into the potential therapeutic applications of S. betaceum by analyzing its polyphenolic content (TPC), total flavonoid content (TFC), anti-skin aging activities against key enzymes like elastase, tyrosinase, and hyaluronidase, and its cytotoxic effects on oral carcinoma cells. Extracts from the seeds, pulp, and peel of red and yellow fruits were prepared using methanol, ethanol, and acetone. The highest TPC was found in the methanol extract from red fruit seeds (9.89 mg GAE/g), and the highest TFC was found in the methanol extract of yellow fruit peel (3.02 mg QUE/g). Some of these extracts significantly inhibited skin aging-associated enzymes with the red fruit seed extract (100 μg/mL) showing up to 50.4% inhibition of tyrosinase. Additionally, the red fruit seed extract obtained using methanol demonstrated potential anticancer effects against Ca9-22 oral carcinoma cells by inhibiting cell survival, migration, and proliferation as well as inducing apoptosis. These results underscore the potential of S. betaceum fruit extracts, especially from red fruit seeds, as promising agents for anti-skin aging and anticancer applications, meriting further exploration for therapeutic uses.

Anti-Skin Aging Potential, Antibacterial Activity, Inhibition of Single-Stranded DNA-Binding Protein, and Cytotoxic Effects of Acetone-Extracted Passiflora edulis (Tainung No. 1) Rind Extract on Oral Carcinoma Cells.

The passion fruit, Passiflora edulis, recognized for its rich nutritional properties, has long been used for its varied ethnobotanical applications. This study investigates the therapeutic potential of P. edulis var. Tainung No. 1 rind extracts by examining their polyphenolic content (TPC), total flavonoid content (TFC), anti-skin aging activities against key enzymes such as elastase, tyrosinase, and hyaluronidase, and their ability to inhibit bacterial growth, single-stranded DNA-binding protein (SSB), and their cytotoxic effects on oral carcinoma cells. The acetone extract from the rind exhibited the highest levels of TPC, TFC, anti-SSB, and antibacterial activities. The antibacterial effectiveness of the acetone-extracted rind was ranked as follows: Escherichia coli > Pseudomonas aeruginosa > Staphylococcus aureus. A titration curve for SSB inhibition showed an IC50 value of 313.2 μg/mL, indicating the potency of the acetone extract in inhibiting SSB. It also significantly reduced the activity of enzymes associated with skin aging, particularly tyrosinase, with a 54.5% inhibition at a concentration of 100 μg/mL. Gas chromatography-mass spectrometry (GC-MS) analysis tentatively identified several major bioactive compounds in the acetone extract, including stigmast-5-en-3-ol, vitamin E, palmitic acid, stigmasterol, linoleic acid, campesterol, and octadecanoic acid. Molecular docking studies suggested some of these compounds as potential inhibitors of tyrosinase and SSB. Furthermore, the extract demonstrated anticancer potential against Ca9-22 oral carcinoma cells by inhibiting cell survival, migration, and proliferation and inducing apoptosis. These results underscore the potential of P. edulis (Tainung No. 1) rind as a promising candidate for anti-skin aging, antibacterial, and anticancer applications, meriting further therapeutic investigation.

Morin overcomes doxorubicin resistance in human breast cancer by inducing DNA damage and modulating the LKB1/AMPK/mTORC1 signaling pathway.

Breast cancer chemoresistance hampers chemotherapy efficacy; researchers investigate the pharmacological activities of natural products for potential solutions. This study aimed to determine the effect of morin, a bioflavonoid isolated from Maclura pomifera, on two Dox-resistant human breast cancer cell lines MDA-MB-231 (MDA-DR) and MCF-7 (MCF-DR). Sulforhodamine B and colony-forming assays demonstrated the cytotoxic effect of morin on both cell lines. Morin induced DNA damage and reduced the DNA repair mechanism, a feature of chemoresistance. In addition, morin reduced the protein expressions of cell cycle regulators, such as cyclin D1, CDK4, cyclin E1, cyclin B1, and p-Rb, thereby halting cell cycle progression. Moreover, morin slightly reduced PARP and Bcl-xL expressions but left LC3-II and RIPK3 expressions unchanged. Annexin-V/7-AAD analysis showed morin increased 7-AAD positive cells and annexin-V positive cells among MDA-DR and MCF-DR cells, respectively. In addition, morin increased p-AMPK and p-LKB1 levels; and, thus, inhibited phosphorylation of the mTOR pathway, but decreased t-AMPK levels by inducing lysosomal degradation, and AICAR, an AMPK activator, reduced Raptor, cyclin D1, CDK4, cyclin E1 and phosphorylated, and total mTOR levels, indicating AMPK is a key player in inducing cell death. Also, morin modulated MAPK phosphorylation and attenuated p-Akt and p-GSK3αβ levels; and thus, inhibited cell survival. In addition, morin suppressed tumor growth in our MDA-DR xenografted mouse model. These findings indicate that morin is a potential treatment for Dox-resistant breast cancer and that it does so by inducing DNA damage and modulating the LKB1/AMPK/mTORC1 pathway, along with regulating the MAPK, and Akt/GSK3αβ signaling pathways.

Biological Activity of Natural and Synthetic Peptides as Anticancer Agents.

Cancer is one of the leading causes of morbidity and death worldwide, making it a serious global health concern. Chemotherapy, radiotherapy, and surgical treatment are the most used conventional therapeutic approaches, although they show several side effects that limit their effectiveness. For these reasons, the discovery of new effective alternative therapies still represents an enormous challenge for the treatment of tumour diseases. Recently, anticancer peptides (ACPs) have gained attention for cancer diagnosis and treatment. ACPs are small bioactive molecules which selectively induce cancer cell death through a variety of mechanisms such as apoptosis, membrane disruption, DNA damage, immunomodulation, as well as inhibition of angiogenesis, cell survival, and proliferation pathways. ACPs can also be employed for the targeted delivery of drugs into cancer cells. With over 1000 clinical trials using ACPs, their potential for application in cancer therapy seems promising. Peptides can also be utilized in conjunction with imaging agents and molecular imaging methods, such as MRI, PET, CT, and NIR, improving the detection and the classification of cancer, and monitoring the treatment response. In this review we will provide an overview of the biological activity of some natural and synthetic peptides for the treatment of the most common and malignant tumours affecting people around the world.

ARID1A is involved in DNA double-strand break repair in gastric cancer.

Defects in DNA damage repair can cause genetic mutations, which in turn can cause different types of cancers. Chromatin remodeling complexes, which help repair damaged DNA, can cause the chromatin structure to change as a result of DNA damage. ARID1A may play a role in the process of DNA damage repair, and arid1a may be related to the occurrence and development of gastric cancer (GC). This study aimed to investigate the mechanism of ARID1A regulating the DNA damage repair of gastric adenocarcinoma cell lines AGS and SGC-7901 and its effect on migration, proliferation and apoptosis. The expression of ARID1A plasmid was detected by Western blot and real-time polymerase chain reaction (PCR). The effect of etoposide (ETO) on the survival rate of AGS and SGC-7901 gastric adenocarcinoma cell lines was detected by MTT assay. The DNA double-strand break model was established by ETO and then passed through the comet assay and immunofluorescence co-localization to observe DNA damage; western blot method was used to detect the effect of ARID1A on the expression of related proteins in DNA damage repair pathway in gastric adenocarcinoma cells; scratch test and colony formation experiments were used to observe ARID1A migration and proliferation of gastric adenocarcinoma cells. The flow cytometry was used to detect the effect of ARID1A on apoptosis of gastric adenocarcinoma cells. The expression of mRNA and protein was increased after transfection of ARID1A plasmid. ETO was confirmed by MTT assay to inhibit cell survival in a dose-dependent manner. After the DNA double-strand break model was established by ETO, the expression levels of phospho-ataxia telangiectasia mutated (p-ATM) protein increased in the overexpressed ARID1A group. Meanwhile, the overexpressed ARID1A group had a shortened tail moment, and γ-H2AX and ARID1A co-localized in the DNA damage site of the nucleus. The over-expressed ARID1A group had weaker wound healing ability, reduced number of clone formation, and increased apoptosis rate. ARID1A may repair DNA double-strand breaks caused by ETO by p-ATM pathway; ARID1A can inhibit the migration and proliferation of gastric adenocarcinoma cells and promote apoptosis. Our findings indicate that ARID1A could serve as a therapeutic target and biomarker for GC patients.

Metformin-induced oxidative stress inhibits LNCaP prostate cancer cell survival.

Preclinical and clinical studies over the past several decades have indicated the potential value of metformin, a widely utilized treatment for Type 2 diabetes, in prostate cancer therapy. Notably, these studies demonstrated metformin's pleiotropic effects on several molecular and metabolic pathways, such as androgen signaling, cell cycle, and cellular bioenergetics. In this study we investigated the role of metformin in regulating intracellular redox status and cell survival in LNCaP prostate cancer cells. The cytotoxic effects of metformin with or without the presence of SBI0206965 (AMPK inhibitor) on LNCaP cells were determined using MTT and trypan blue exclusion assays. Seahorse XP extracellular analysis, Liquid Chromatography/ Mass Spectrophotometry (LC/MS), and 2,7- and Dichlorofluoresin diacetate (DCFDA) assay were used to assess the effects of metformin on cellular bioenergetics, redox status, and redox-related metabolites. mRNA expression and protein concentration of redox-related enzymes were measured using Real Time-qPCR and ELISA assay, respectively. Independently of AMP-activated protein kinase, metformin exhibited a dose- and time-dependent inhibition of LNCaP cell survival, a response mitigated by glutathione or N-acetylcysteine (ROS scavengers) treatment. Notably, these findings were concomitant with a decline in ATP levels and the inhibition of oxidative phosphorylation. The results further indicated metformin's induction of reactive oxygen species, which significantly decreased glutathione levels and the ratio of reduced to oxidized glutathione, as well as the transsulfuration metabolite, cystathionine. Consistent with an induction of oxidative stress condition, metformin increased mRNA levels of the master redox transcription factor Nrf-2 (nuclear factor erythroid-derived 2-like), as well as transsulfuration enzymes cystathionine beta-synthase and cystathionase and GSH synthesis enzymes γ-glutamylcysteine synthetase and glutathione synthetase. Our findings highlight multiple mechanisms by which metformin-induced formation of reactive oxygen species may contribute to its efficacy in prostate cancer treatment, including promotion of oxidative stress, Nrf2 activation, and modulation of redox-related pathways, leading to its anti-survival action.

Integrated Transcriptome Analysis of Radioresistant Cells Revealed Genes and Pathways Predictive Of Tumor Response to Radiotherapy and Chemotherapy in Breast Cancer

AbstractBreast cancer cells exposed to radiotherapy frequently develop radiation resistance through molecular and phenotypic changes. While there is evidences of pathways controlling radioresistance, the evolution of diverse cell phenotypes and transcriptional changes as mediators of radioresistance in breast cancer are restricted. Moreover, the effectiveness of the chemotherapy on radioresistant cells remains uncertain. In this work, an isogenic model of radioresistant breast cancer cells (RR cells) is used to study this phenotype. RR cells show high survival rates after radiation, moreover, RR cells of the triple negative breast cancer (TNBC) subtype show a significantly advanced invasiveness phenotype. Notably, RR cells are significantly sensitive to chemotherapy by inhibit cell survival and promote apoptosis. Transcriptomics and gene co‐expression network analysis identify differentially expressed genes (DEGs) and hub genes related to survival and apoptosis pathways in the RR cells of luminal subtype, while in TNBC subtype, cell migration, cell differentiation, and immune pathways are enriched. Hub genes predict the failure of radiotherapy in breast cancer patients, but they are also related to pathological complete response after chemotherapy. Transcriptome changes during acquired radioresistance uncover genes and pathways associated to radio and chemotherapy response. These results demonstrate that radioresistant pathways may converge to develop collateral chemo‐sensitivity.

Lysophosphatidic Acid Receptor 1 (LPA1) Antagonists as Potential Migrastatics for Triple Negative Breast Cancer.

Metastasis is responsible for about 90 % of cancer deaths. Anti-metastatic drugs, termed as migrastatics, offer a distinctive therapeutic approach to address cancer migration and invasion. However, therapeutic exploitation of metastasis-specific targets remains limited, and the effective prevention and suppression of metastatic cancer continue to be elusive. Lysophosphatidic acid receptor 1 (LPA1) is activated by an endogenous lipid molecule LPA, leading to a diverse array of cellular activities. Previous studies have shown that the LPA/LPA1 axis supports the progression of metastasis for many types of cancer. In this study, we report the synthesis and biological evaluation of fluorine-containing triazole derivatives as potent LPA1 antagonists, offering potential as migrastatic drugs for triple negative breast cancer (TNBC). In particular, compound 12 f, the most potent and highly selective in this series with an IC50 value of 16.0 nM in the cAMP assay and 18.4 nM in the calcium mobilization assay, inhibited cell survival, migration, and invasion in the TNBC cell line. Interestingly, the compound did not induce apoptosis in TNBC cells and demonstrated no cytotoxic effects. These results highlight the potential of LPA1 as a migrastatic target. Consequently, the LPA1 antagonists developed in this study hold promise as potential migrastatic candidates for TNBC.

MiR-1202 regulates BPH-1 cell proliferation, apoptosis, and epithelial-to-mesenchymal transition through targeting HMGCL.

Benign prostatic hyperplasia (BPH) is the expansion of the prostate gland that results in urinary symptoms. Both the epithelial-to-mesenchymal transition (EMT) and the Wnt signaling pathway are associated with BPH pathology. In this study, we find that miR-1202 is increased in BPH samples. Overexpression of miR-1202 in TGF-β-treated BPH-1 cells enhances cell survival and DNA synthesis and inhibits cell apoptosis, whereas miR-1202 inhibition partially abolishes the effects of TGF-β on BPH-1 cells. miR-1202 overexpression reduces E-cadherin level but elevates vimentin, N-cadherin, and snail levels, whereas miR-1202 inhibition partially attenuates the effects of TGF-β on EMT markers. Regarding the Wnt/β-catenin pathway, miR-1202 overexpression significantly enhances, whereas miR-1202 inhibition partially decreases, the promotive effects of TGF-β on Wnt1, c-Myc, and cyclin D1 proteins. 3-Hydroxy-3-methylglutaryl-CoA lyase (HMGCL) is a direct downstream target of miR-1202, and miR-1202 inhibits HMGCL expression through binding to its 3'UTR. Overexpression of HMGCL significantly reduces the effect of miR-1202 overexpression on the phenotypes of BPH-1 cells by inhibiting cell survival and promoting apoptosis. Similarly, HMGCL overexpression has the opposite effects on EMT markers and the Wnt/β-catenin signaling, and markedly alleviates the effects of miR-1202 overexpression. Finally, in the BPH rat model, Ki67 and vimentin levels are elevated, but E-cadherin and HMGCL levels are reduced. In conclusion, miR-1202 is upregulated in benign prostatic hyperplasia; miR-1202 enhances epithelial cell proliferation, suppresses cell apoptosis, and promotes EMT by targeting HMGCL. The Wnt/β-catenin pathway may participate in the miR-1202/HMGCL axis-mediated regulation of BPH-1 cell phenotypes.

RAF1 facilitates KIT signaling and serves as a potential treatment target for gastrointestinal stromal tumor.

The aberrant activation of RAS/RAF/MEK/ERK signaling is important for KIT mutation-mediated tumorigenesis of gastrointestinal stromal tumor (GIST). In this study, we found that inhibition of RAF1 suppresses the activation of both wild-type KIT and primary KIT mutations in GIST, with primary KIT mutations showing greater sensitivity. This suggests a positive feedback loop between KIT and RAF1, wherein RAF1 facilitates KIT signaling. We further demonstrated that RAF1 associates with KIT and the kinase activity of RAF1 is necessary for its contribution to KIT activation. Accordingly, inhibition of RAF1 suppressed cell survival, proliferation, and cell cycle progression in vitro mediated by both wild-type KIT and primary KIT mutations. Inhibition of RAF1 in vivo suppressed GIST growth in a transgenic mouse model carrying germline KIT/V558A mutation, showing a similar treatment efficiency as imatinib, the first-line targeted therapeutic drug of GIST, while the combination use of imatinib and RAF1 inhibitor further suppressed tumor growth. Acquisition of drug-resistant secondary mutation of KIT is a major cause of treatment failure of GIST following targeted therapy. Like wild-type KIT and primary KIT mutations, inhibition of RAF1 suppressed the activation of secondary KIT mutation, and the cell survival, proliferation, cell cycle progression in vitro, and tumor growth in vivo mediated by secondary KIT mutation. However, the activation of secondary KIT mutation is less dependent on RAF1 compared with that of primary KIT mutations. Taken together, our results revealed that RAF1 facilitates KIT signaling and KIT mutation-mediated tumorigenesis of GIST, providing a rationale for further investigation into the use of RAF1 inhibitors alone or in combination with KIT inhibitor in the treatment of GIST, particularly in cases resistant to KIT inhibitors.

Polyphyllin I ameliorates gefitinib resistance and inhibits the VEGF/VEGFR2/p38 pathway by targeting HIF-1a in lung adenocarcinoma

BackgroundLung adenocarcinoma (LUAD) is the most common pathological type of lung cancer. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have been administered as the first-line therapy for patients with EGFR mutations in LUAD, but it is almost inevitable that resistance to EGFR-TKIs therapy eventually arises. Polyphyllin I (PPI), derived from Paris polyphylla rhizomes, has been shown to have potent anti-cancer properties in a range of human cancer types including LUAD. However, the role of PPI in gefitinib resistance and the underlying mechanism remain elusive. PurposeTo evaluate the antitumor impacts of PPI on gefitinib resistance cells and investigate its molecular mechanism. MethodsCCK-8, wound healing, transwell assay, and xenograft model were performed to determine the anti-cancer effects of PPI as well as its ability to overcome gefitinib resistance. Immunoblotting, co-immunoprecipitation, phospho-RTK antibody array, qRT-PCR, and immunofluorescence were utilized to explore the mechanism by which PPI overrides gefitinib resistance. ResultsPPI inhibited cell survival, growth, and migration/invasion in both gefitinib-sensitive (PC9) and -resistant (PC9/GR) LUAD cells (IC50 at 2.0 μM). Significantly, treatment with PPI at 1.0 μM resensitized the resistant cells to gefitinib. Moreover, cell-derived xenograft experiments revealed that the combination of PPI and gefitinib overcame gefitinib resistance. The phospho-RTK array and immunoblotting analyses showed PPI significant inhibition of the VEGFR2/p38 pathway. In addition, molecular docking suggested the interaction between PPI and HIF-1α. Mechanistically, PPI reduced the protein expression of HIF-1α in both normoxia and hypoxia conditions by triggering HIF-1α degradation. Moreover, HIF-1α protein but not mRNA level was elevated in gefitinib-resistant LUAD. We further demonstrated that PPI considerably facilitated the binding of HIF-1α to VHL. ConclusionsWe present a novel discovery demonstrating that PPI effectively counteracts gefitinib resistance in LUAD by modulating the VEGF/VEGFR2/p38 pathway. Mechanistic investigations unveil that PPI facilitates the formation of the HIF-1α /VHL complex, leading to the degradation of HIF-1α and subsequent inhibition of angiogenesis. These findings uncover a previously unidentified mechanism governing HIF-1α expression in reaction to PPI, providing a promising method for therapeutic interventions targeting EGFR-TKI resistance in LUAD.

Synthesis and antitumor activity of dolutegravir derivatives bearing 1,2,3-triazole moieties

Modification of marketed drugs is an important way to develop drugs because its safety and clinical applicability. Oxygen-nitrogen heterocycles are a class of important active substances discovered in the process of new drug development. Dolutegravir, an HIV drug with a nitrogen-oxygen heterocycle structure, has the potential ability to inhibit cell survival. In order to find and explore novel anti-tumor drugs, new dolutegravir derivatives bearing different 1,2,3-triazole moieties were prepared via click reactions. In vitro biological experiments performed in several lung cancer cell lines suggested that these novel compounds displayed potent anti-tumor ability. Especially, the compound 9e with a substituent of 2-methyl-3-nitrophenyl and the compound 9p with a substituent of 3-trifluoromethylphenyl were effective against PC-9 cell line with IC50 values of 3.83 and 3.17 µM, respectively. Moreover, compounds 9e and 9p were effective against H460 and A549 cells. Further studies suggested that compounds 9e and 9p could induce cancer cell apoptosis in PC-9 and H460, inhibit cancer cell proliferation, change the cell cycle, and increase the level of reactive oxygen species (ROS) which further induce tumor cell apoptosis. In addition, compounds 9e and 9p increased LC3 protein expression which was the key regulator in autophagy signaling pathway in PC-9 cells. Compound 9e also showed low toxicity against normal cells, and could be regarded as an interesting lead compound for further structure optimization.

In vitro effects and mathematical modelling of CTCE-9908 (a chemokine receptor 4 antagonist) on melanoma cell survival.

CTCE-9908, a CXC chemokine receptor 4 (CXCR4) antagonist, prevents CXCR4 phosphorylation and inhibits the interaction with chemokine ligand 12 (CXCL12) and downstream signalling pathways associated with metastasis. This study evaluated the in vitro effects of CTCE-9908 on B16 F10 melanoma cells with the use of mathematical modelling. Crystal violet staining was used to construct a mathematical model of CTCE-9908 B16 F10 (melanoma) and RAW 264.7 (non-cancerous macrophage) cell lines on cell viability to predict the half-maximal inhibitory concentration (IC50). Morphological changes were assessed using transmission electron microscopy. Flow cytometry was used to assess changes in cell cycle distribution, apoptosis via caspase-3, cell survival via extracellular signal-regulated kinase1/2 activation, CXCR4 activation and CXCL12 expression. Mathematical modelling predicted IC50 values from 0 to 100 h. At IC50, similar cytotoxicity between the two cell lines and ultrastructural morphological changes indicative of cell death were observed. At a concentration 10 times lower than IC50, CTCE-9908 induced inhibition of cell survival (p = 0.0133) in B16 F10 cells but did not affect caspase-3 or cell cycle distribution in either cell line. This study predicts CTCE-9908 IC50 values at various time points using mathematical modelling, revealing cytotoxicity in melanoma and non-cancerous cells. CTCE-9908 significantly inhibited melanoma cell survival at a concentration 10 times lower than the IC50 in B16 F10 cells but not RAW 264.7 cells. However, CTCE-9908 did not affect CXCR4 phosphorylation, apoptosis,\ or cell cycle distribution in either cell line.

Inhibition of Prostate Cancer Cell Survival and Proliferation by Carnosic Acid Is Associated with Inhibition of Akt and Activation of AMPK Signaling.

Prostate cancer, accounting for 375,304 deaths in 2020, is the second most prevalent cancer in men worldwide. While many treatments exist for prostate cancer, novel therapeutic agents with higher efficacy are needed to target aggressive and hormone-resistant forms of prostate cancer, while sparing healthy cells. Plant-derived chemotherapy drugs such as docetaxel and paclitaxel have been established to treat cancers including prostate cancer. Carnosic acid (CA), a phenolic diterpene found in the herb rosemary (Rosmarinus officinalis) has been shown to have anticancer properties but its effects in prostate cancer and its mechanisms of action have not been examined. CA dose-dependently inhibited PC-3 and LNCaP prostate cancer cell survival and proliferation (IC50: 64, 21 µM, respectively). Furthermore, CA decreased phosphorylation/activation of Akt, mTOR, and p70 S6K. A notable increase in phosphorylation/activation of AMP-activated kinase (AMPK), acetyl-CoA carboxylase (ACC) and its upstream regulator sestrin-2 was seen with CA treatment. Our data indicate that CA inhibits AKT-mTORC1-p70S6K and activates Sestrin-2-AMPK signaling leading to a decrease in survival and proliferation. The use of inhibitors and small RNA interference (siRNA) approaches should be employed, in future studies, to elucidate the mechanisms involved in carnosic acid's inhibitory effects of prostate cancer.