Calcimycin mediates apoptosis in breast and cervical cancer cell lines by inducing intracellular calcium levels in a P2RX4-dependent manner

BACKGROUND

Calcimycin (A23187) is a polyether antibiotic and divalent cation ionophore, extracted from Streptomyces chartrecensis. With wide variety of antimicrobial activities, it also exhibits cytotoxicity of tumor cells. Calcimycin exhibit therapeutic potential against tumor cell growth; however, the molecular mechanism remains to be fully elucidated. Present study explores the mechanism of calcimycin-induced apoptosis cancer cell lines.

METHODS

Apoptotic induction in a dose-dependent manner were recorded with MTT assays, Phase contrast imaging, wound healing assay, fluorescence imaging by DAPI and AO/EB staining and FACS using cell line model. Mitochondrial potential was analyzed by TMRM assay as Ca2+ signaling is well known to be influenced and synchronized by mitochondria also.

RESULTS

Calcimycin induces apoptosis in dose dependent manner, also accompanied by increased intracellular calcium-level and expression of purinergic receptor-P2RX4, a ligand-gated ion channel.

CONCLUSION

Calcimycin tends to increase the intracellular calcium level, mRNA expression of ATP receptor P2RX4, and phosphorylation of p38. Blocking of either intracellular calcium by BAPTA-AM, P2RX4 expression by antagonist 5-BDBD, and phospho-p38 by SB203580, abrogated the apoptotic activity of calcimycin.

GENERAL SIGNIFICANCE

Taken together, these results show that calcimycin induces apoptosis in P2RX4 and ATP mediated intracellular Ca2+ and p38 MAPK mediated pathway in both the cancer cell lines. This study explored a new mode of action for calcimycin in cancer that could be potentially employed in future studies for cancer therapeutic research. This study disentangles that the calcimycin-induced apoptotic cell death is P2RX4 and ATP involved, intracellular Ca2+ and p38 MAPK mediated pathway.

Licochalcone A induces cell cycle arrest and apoptosis via suppressing MAPK signaling pathway and the expression of FBXO5 in lung squamous cell cancer

Lung squamous cell carcinoma (LSCC) is a highly heterogeneous malignancy with high mortality and few therapeutic options. Licochalcone A (LCA, PubChem ID: 5318998) is a chalcone extracted from licorice and possesses anticancer and anti‑inflammatory activities. The present study aimed to elucidate the anticancer effect of LCA on LSCC and explore the conceivable molecular mechanism. MTT assay revealed that LCA significantly inhibited the proliferation of LSCC cells with less cytotoxicity towards human bronchial epithelial cells. 5‑ethynyl‑2'‑deoxyuridine (EdU) assay demonstrated that LCA could reduce the proliferation rate of LSCC cells. The flow cytometric assays indicated that LCA increased the cell number of the G1 phase and induced the apoptosis of LSCC cells. LCA downregulated the protein expression of cyclin D1, cyclin E, CDK2 and CDK4. Meanwhile, LCA increased the expression level of Bax, cleaved poly(ADP‑ribose)polymerase‑1 (PARP1) and caspase 3, as well as downregulated the level of Bcl‑2. Proteomics assay demonstrated that LCA exerted its antitumor effects via inhibiting mitogen‑activated protein kinase (MAPK) signaling pathways and the expression of F‑box protein 5 (FBXO5). Western blot analysis showed that LCA decreased the expression of p‑ERK1/2, p‑p38MAPK and FBXO5. In the xenograft tumors of LSCC, LCA significantly inhibited the volumes and weight of tumors in nude mice with little toxicity in vital organs. Therefore, the present study demonstrated that LCA effectively inhibited cell proliferation and induced apoptosis in vitro, and suppressed xenograft tumor growth in vivo. LCA may serve as a future therapeutic candidate of LSCC.

Evaluation of the anticancer effect of telomerase inhibitor BIBR1532 in anaplastic thyroid cancer in terms of apoptosis, migration and cell cycle

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 G0/G1 phase and 27.6% arrest in the S phase of the cell cycle in untreated group, treatment with BIBR1532 increased cell population in G0/G1 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.

A Selective Nano Cell Cycle Checkpoint Inhibitor Overcomes Leukemia Chemoresistance

Cell cycle checkpoint activation promotes DNA damage repair, which is highly associated with the chemoresistance of various cancers including acute myeloid leukemia (AML). Selective cell cycle checkpoint inhibitors are strongly demanded to overcome chemoresistance, but remain unexplored. A selective nano cell cycle checkpoint inhibitor (NCCI: citric acid capped ultra-small iron oxide nanoparticles) that can catalytically inhibit the cell cycle checkpoint of AML to boost the chemotherapeutic efficacy of genotoxic agents is now reported. NCCI can selectively accumulate in AML cells and convert H2 O2 to • OH to cleave heat shock protein 90, leading to the degradation of ataxia telangiectasia and Rad3-related proteinand checkpoint kinase 1, and the subsequent dysfunction of the G2/M checkpoint. Consequently, NCCI revitalizes the anti-AML efficacy of cytarabine that is previously ineffective both in vitro and in vivo. This study offers new insights into designing selective cell cycle checkpoint inhibitors for biomedical applications.

Anti-proliferative effect of melatonin in human hepatoma HepG2 cells occurs mainly through cell cycle arrest and inflammation inhibition

Hepatocellular carcinoma (HCC) is the major lethal primary liver malignant worldwide. Although, melatonin has various antitumor bioactivities; there is a requirement for more investigations to elucidate the not discussed effects, and the controversial responses of the treatment with melatonin on targets mediated in HCC. To achieve the aim of the present study, HCC-HepG2 cells were treated with different concentrations of melatonin at various time intervals. The selected minimal proliferation inhibition doses of melatonin were then incubated with cells to examine the arresting effect of melatonin on dividing cells using flow cytometry. Furthermore, the molecular patterns of genes that contributed to apoptosis, drug resistance development, antioxidation, and melatonin crossing were quantified by qRT-PCR. Additionally, the Human inflammation antibody array membrane (40 targets) was used to check the anti-inflammatory effect of melatonin. Our results validated that, melatonin shows anti-proliferative action through preserving cells in G0/G1 phase (P < 0.001) that is associated with a highly significant increase in the expression level of the P53 gene (P < 0.01). On contrary, as a novelty, our data recorded decreases in expression levels of genes involved in the pro-apoptotic pathway; with a significant increase (P < 0.05) in the expression level of an anti-apoptotic gene, Bcl2. Interestingly, we detected observed increases in the expression levels of genes responsible for conferring drug resistance including ABCB1, ABCC1, and ABCC5. Our study proved the anti-inflammatory activity of 1 mM melatonin in HCC-HepG2 cells. Accordingly, we can conclude that melatonin facilitates the anti-proliferation of cells at doses of 1 mM, and 2.5 mM after 24 h. This action is initiated through cell cycle arrest at G0/G1 phase via increasing the expression of P53, but independently on apoptosis. Collectively, melatonin is an effective anti-inflammatory and anti-proliferative promising therapy for the treatment of HCC. However, its consumption should be cautious to avoid the development of drug resistance and provide a better treatment strategy.

Bisphenol A modulates proliferation, apoptosis, and wound healing process of normal prostate cells: Involvement of G2/M-phase cell cycle arrest, MAPK signaling, and transcription factor-mediated MMP regulation

Bisphenol A (BPA) is commonly used to produce epoxy resins and polycarbonate plastics. BPA is an endocrine-disrupting chemical that is leaked from the polymer and absorbed into the body to disrupt the endocrine system. Although BPA may cause cytotoxicity in the prostate, a hormone-dependent reproductive organ, its underlying mechanism has not yet been elucidated. Here, we investigated the effects of BPA on cell proliferation, apoptosis, and the wound healing process using prostate epithelial cells (RWPE-1) and stromal cells (WPMY-1). Observations revealed that BPA induced G2/M cell cycle arrest in both cell types through the ATM-CHK1/CHK2-CDC25c-CDC2 signaling pathway, and the IC₅₀ values were estimated to be 150 μM. Furthermore, BPA was found to induce caspase-dependent apoptosis through initiator (caspase-8 and -9) and executioner (caspase-3 and -7) caspase cascades. In addition, BPA interfered with the wound healing process through inhibition of MMP-2 and - 9 expression, accompanied by reductions in the binding activities of AP-1 as well as NF-κB motifs. Phosphorylation of MAPKs was associated with the BPA-mediated toxicity of prostate cells. These results suggest that BPA exhibits prostate toxicity by inhibiting cell proliferation, inducing apoptosis, and interfering with the wound healing process. Our study provided new insights into the precise molecular mechanisms of BPA-induced toxicity in human prostate cells.

Nrf2 affects hydroquinone-induces cell cycle arrest through the p16/pRb signaling pathway and antioxidant enzymes

Hydroquinone (HQ), a well-known carcinogenic agent, induces oxidative stress, cell cycle arrest, apoptosis, and malignant transformation. As an antioxidant actor, the nuclear factor erythroid 2-related factor 2 (Nrf2) drives adaptive cellular protection in response to oxidative stress. The human lymphoblastoid cell line (TK6 cells) is widely used as a model for leukemia researches. In the present study, we focused on exploring whether Nrf2 regulatory cell cycle in TK6 cells upon HQ treatment and the underlying mechanisms. The results showed that the cell cycle arrest in TK6 cells induced by hydroquinone was accompanied by activation of the Nrf2 signaling pathway. We further clarified that Nrf2 loss accelerated cell cycle progression from G0/G1 to S and G2/M phases and promoted ROS production by downregulating the expression of SOD and GSH. Western blotting analysis indicated that Nrf2 regulated cell cycle progression via p16/pRb signaling pathways. Therefore, we conclude that Nrf2 is engaged in HQ-induced cell cycle arrest as well through p16/pRb and antioxidant enzymes.

Zanthoxylum bungeanum seed oil inhibits RANKL-induced osteoclastogenesis by suppressing ERK/c-JUN/NFATc1 pathway and regulating cell cycle arrest in RAW264.7 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Zanthoxylum bungeanum Maxim (ZBM), a traditional Chinese medicine, is traditionally used for osteoporosis treatment recorded in ancient Chinese medicine work Benjingshuzheng and reported to have the anti-bone loss activity in recent studies. However, the anti-osteoporotic activities of the seed of ZBM have not been elucidated yet. Our previous study found that Zanthoxylum bungeanum Maxim seed oil (ZBSO) was rich in polyunsaturated fatty acids (PUFAs), which were reported to prevent bone loss. Thus, we propose a hypothesis that ZBSO could be a potential natural resource for anti-bone loss.

AIM OF THE STUDY

To investigate whether ZBSO could prevent bone loss by targeting osteoclastogenesis and investigate the potential mechanisms in receptor-activator of nuclear factor κB ligand (RANKL)-induced RAW264.7 cells.

MATERIALS AND METHODS

RAW264.7 cells were treated with RANKL in the presence or absence of ZBSO. The effect of ZBSO on osteoclast differentiation and bone resorption activity of RAW264.7 cells were evaluated by tartrate-resistant acid phosphatase (TRAP) staining, F-actin ring staining, and bone resorption assay. Differentially expression genes (DEGs) and relevant pathways of different cell groups were obtained from RNA sequencing and protein-protein interaction (PPI) network analysis followed by KEGG pathway enrichment analysis. The effect of ZBSO on the RANKL-induced cell cycle change was analyzed by flow cytometry assay, and the expression of genes and proteins related to the selected pathways was further verified by RT-qPCR and western blot analysis.

RESULTS

The inhibitory effects of ZBSO on osteoclast differentiation and bone resorption activity in a dose-dependent manner were demonstrated by TRAP staining, F-actin ring staining, and bone resorption assay in RANKL-induced RAW264.7 cells. Osteoclast differentiation and cell cycle pathways were the most enriched pathways based on DEGs enrichment analysis among different cell groups. The reversion effect of ZBSO on the RANKL-induced RAW264.7 cell cycle arrest at the G1 phase was observed by flow cytometry assay. Western blot results showed that ZBSO markedly decreased RANKL-induced activation of ERK, as well as the phosphorylation of c-JUN and NFATc1 expression, and subsequently suppressed osteoclast-specific genes, such as Ctsk, Trap, and Dc-stamp.

CONCLUSIONS

ZBSO exhibited an inhibitory effect on osteoclastogenesis via suppressing the ERK/c-JUN/NFATc1 pathway and regulating cell cycle arrest induced by RANKL, suggesting that ZBSO may serve as a promising agent for anti-bone loss.

Silybin B exerts protective effect on cisplatin-induced neurotoxicity by alleviating DNA damage and apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Silybum marianum is a traditional Chinese medicine that has been used for treating liver disease. Silybin consisting of silybin A and silybin B, is a member of Silybum marianum, and exerts a therapeutic effect on many diseases. However, the protective effect of silybin on cisplatin-induced neurotoxicity and the stereoisomer contributing to the effect remain unknown.

AIM OF THE STUDY

The present study aimed to study the effect of silybin on cisplatin-induced neuronal injury, compare the difference of protective effect between silybin A and silybin B, and the potential mechanism.

MATERIALS AND METHODS

High performance liquid chromatography (HPLC) was used to separate silybin A and silybin B. X-ray crystallographic analysis in combination with experimental and calculated ECD were performed to identify the structure of silybin A and silybin B. The toxicity of the silybin or cisplatin against murine hippocampal neuronal HT22 cells was determined through MTT assay. The cell cycle and cell apoptosis were measured by PI staining and Annexin V-FITC/PI staining, respectively, and then subjected to flow cytometry. Western blot analysis was conducted to quantify the expression of proteins related to apoptosis and DNA damage. Immunofluorescence was used to evaluate the expression of DNA damage marker. In vivo experiment, the behavioral analysis was determined through pole test, swimming test and Morris water maze test. The index of superoxide dismutase (SOD), reduced glutathione (GSH), total antioxidant capacity (T-AOC) and lipid peroxidation (LPO) were examined to evaluate the antioxidant capacity in mice brain. Nissl staining and Tunel assay were used to detect the neuronal viability and apoptosis in hippocampus.

RESULTS

We successfully separated and identified silybin A and silybin B. We found both silybin A and silybin B alleviated cisplatin-induced apoptosis and cell cycle arrest in HT22 cells, and silybin B was more effective. We chose silybin B for further mechanism investigation, and found silybin B alleviated DNA damage by enhancing phosphorylation of ATR and decreasing expression of γ-H2AX. In the in vivo experiment, we observed that silybin B markedly improved the behavioral abnormalities in cisplatin-treated mice, reduced LPO level while increased SOD, GSH and T-AOC in mice brain tissue. Nissl staining and Tunel assay showed that silybin B alleviated cisplatin-induced hippocampal damage.

CONCLUSIONS

These results suggest that silybin B might serve as a promising drug candidate in mitigating cisplatin-induced neural injury in the brain and thereby improving the chemotherapeutic outcomes.

Matrine injection inhibits pancreatic cancer growth via modulating carbonic anhydrases- a network pharmacology-based study with in vitro validation

ETHNOPHARMACOLOGICAL RELEVANCE

Matrine injection is a complex mixture of plant bioactive substances extracted from Sophora flavescens Aiton and Smilax glabra Roxb. Since its approval by the Chinese Food and Drug Administration (CFDA) in 1995, Matrine injection has been clinically used as a complementary and alternative treatment for various cancers; however, the underlying mechanism of pancreatic cancer treatment is yet to be elucidated.

AIM OF THE STUDY

The present study explores the potential mechanism of matrine injection on pancreatic cancer through network pharmacology technique and in vitro experimental validation.

MATERIALS AND METHODS

Genes differentially expressed in pancreatic cancer were obtained from the Gene Expression Omnibus (GEO) database (GSE101448). The potential active components of matrine injection were selected following a literature search, and target prediction was performed by the SwissTarget Prediction database. Overlapping genes associated with survival were screened by the Gene Expression Profiling Interactive Analysis (GEPIA) database. In vitro experimental validation was performed with cell counting kit-8 (CCK-8) assay, apoptosis detection, cell cycle analysis, immunoblotting, and co-immunoprecipitation of the identified proteins.

RESULTS

One thousand seven hundred genes differentially expressed among pancreatic tumor and non-tumor tissues were screened out. Sixteen active components and 226 predicted target genes were identified in matrine injection. A total of 25 potential target genes of matrine injection for the treatment of pancreatic cancer were obtained. Among them, the prognostic target genes carbonic anhydrase 9 (CA9) and carbonic anhydrase 12 (CA12) based on the GEPIA database are differently expressed in tumors compared to adjacent normal tissue. In vitro experiments, the results of CCK-8 assay, apoptosis and cell cycle analysis, immunoblotting, and co-immunoprecipitation showed that matrine injection inhibited Capan-1 and Mia paca-2 proliferation, arrested the cell cycle at the S phase, and induced apoptosis through up-regulated CA12 and down-regulated CA9.

CONCLUSIONS

In this study, bioinformatics and network pharmacology were applied to explore the treatment mechanism on pancreatic cancer with matrine injection. This study demonstrated that matrine injection inhibited proliferation, arrested the cell cycle, and induced apoptosis of pancreatic cancer cells. The mechanism may be related to the induction of CA12 over-expression, and CA9 reduced expression. As novel targets for pancreatic cancer treatment, Carbonic anhydrases require further study.

Bolbostemma paniculatum (Maxim.) Franquet extract suppresses the development of colorectal cancer through downregulation of PI3K/Akt pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Bolbostemma paniculatum (Maxim.) Franquet (BPF), a kind of Chinese medicine, has been traditionally used in treating mastitis, dysentery, phlegm nuclear, and sore swelling poison.

AIM OF THE STUDY

In current study, we tried to investigate the possible anti-colorectal cancer (CRC) effects of BPF.

MATERIALS AND METHODS

The effects of BPF extract on human colon cancer cells HCT-116 and SW-620, and a colitis associated colorectal cancer (CACC) mouse model were evaluated using the method of experimental pharmacology combined with network pharmacology.

RESULTS

The ethyl acetate extract 3 (EA3) of BPF showed the most potent growth inhibitory effect in CRC cells. It could inhibit the clone formation, induce the apoptosis and cell cycle arrest in G1 phase as well as suppress the invasion and migration of CRC cells. And EA3 prevented ICR mice against CACC effectively. Both KEGG and GO analysis indicated that EA3 may inhibit CRC through influencing PI3K/Akt pathway. Results of Western blot analysis and ELISA confirmed that the molecules in the pathway were affected by EA3.

CONCLUSIONS

These results demonstrate that EA3 from BPF could suppress the development of CRC through inhibiting the activity of PI3K/Akt pathway.

Anticancer effects of Pimaric acid is mediated via endoplasmic reticulum stress, caspase-dependent apoptosis, cell cycle arrest, and inhibition of cell migration in human ovarian cancer cells

Pimaric acid is a naturally occurring resin and has been found to perform many pharmacological activities including, anticancer activity. However, the role of Pimaric acid in ovarian cancer is still not known. This investigation aimed to evaluate the anticancer effects of Pimaric acid and its molecular mechanism in human ovarian cancer cells. MTT assay was used to examine cell viability. Cell morphology was determined through phase contrast microscopy. DAPI staining and TUNEL assay were performed for apoptotic study. Examination of cell cycle phase distribution was carried out through flow cytometry. In vitro wound healing assay was used for cell migration determination. Pimaric acid induced cytotoxicity in human ovarian cancer cells (PA-1) in a dose-dependent manner without causing too much cytotoxicity in human ovarian epithelial cells (T1074). Cell morphology in treated cancer cells showed significant changes compared to untreated controls. Furthermore, it was observed that the cytotoxic effects of Pimaric acid were apoptosis-mediated and caspase-dependent cascade. Western blotting analysis showed that the expression of apoptosis-associated proteins like BAX, p-53 and caspase-3 was enhanced and BCL-2 expression was diminished. The induction of cytotoxicity was mediated via endoplasmic reticulum stress through expressions of related proteins which showed a tremendous increase in p-PERK, PERK, AT-4, CHOP and IRE-1 levels after treatment. Cell cycle analysis through cytometry showed significant results as it revealed G2/M phase cell cycle arrest. Furthermore, the in vitro wound healing assay showed specific anti-migratory effects of Pimaric acid on PA-1 cells. In conclusion it can be assumed that Pimaric acid may act as a potential anticancer agent against ovarian carcinoma, however further investigations are required to validate this initial claim.

Granatin B and punicalagin from Chinese herbal medicine pomegranate peels elicit reactive oxygen species-mediated apoptosis and cell cycle arrest in colorectal cancer cells

BACKGROUND

Colorectal cancer ranks among the most common cancers. 5-Fluorouracil (5-FU) based first-line chemotherapy for colorectal cancer treatment often leads to chemoresistance and gastrointestinal mucositis.

PURPOSE

This study aimed to find potential therapeutic agents from herbal medicine with anti-colorectal cancer and anti-mucositis activities.

METHODS

Chinese medicine theory, network pharmacology analyses, and antioxidant activity coupled with liquid chromatography tandem mass spectrometry analyses were used to identify potential bioactive compounds. HT-29 human colorectal cancer cell culture and xenograft tumor models were employed to study anti-colorectal cancer efficacy. Lipopolysaccharide-induced RAW 264.7 and 5-FU treated Dark Agouti rats were used to evaluate anti-inflammatory and anti-mucositis activities. Histological staining, immunofluorescence imaging, western blots, and flow cytometric analyses were employed to explore the underlying mechanisms.

RESULTS

Both Chinese medicine theory and network pharmacology analyses indicated pomegranate peels as a potential anti-colorectal cancer and anti-mucositis agent. Antioxidant activity coupled with liquid chromatography tandem mass spectrometry analyses revealed granatin B and punicalagin as the most potent antioxidant compounds in pomegranate peels. Granatin B and punicalagin demonstrated superior anti-colorectal cancer activities in both cell culture and xenograft tumor models. Granatin B and punicalagin also exhibited strong anti-inflammatory activities in lipopolysaccharide-induced RAW264.7 cells and anti-mucositis activities in 5-FU-treated rats. Mechanistic studies revealed that granatin B and punicalagin induced reactive oxygen species-mediated S-phase cell cycle arrest and apoptosis in HT-29 cells. Moreover, these compounds sensitized HT-29 cells to 5-FU-induced cell death and S-phase cell cycle arrest.

CONCLUSION

We report that granatin B and punicalagin exhibit superior anti-colorectal cancer and anti-mucositis activities. To the best of our knowledge, these results are novel and suggest that utilizing phenols from herbal medicine, such as granatin B and punicalagin, to target reactive oxygen species may be an innovative therapy to treat colorectal cancer and intestinal mucositis.

Inhibition of FGFR2 enhances chemosensitivity to gemcitabine in cholangiocarcinoma through the AKT/mTOR and EMT signaling pathways

AIM

To investigate the oncogenic role of FGFR2 in carcinogenesis in cholangiocarcinoma (CCA) cells. In addition, the feasibility of using FGFR inhibitors in combination with standard chemotherapy was also explored for the chemosensitizing effect in CCA cells.

MAIN METHODS

Five CCA cell lines were used to screen FGFR2 expression by Western immunoblotting. Two CCA cell lines, KKU-100 and KKU-213A, were knocked down of the FGFR2 gene using siRNA. Cell viability was assessed by the MTS cell proliferation assay. Reproductive cell death was assessed by clonogenic assay. The effects on cell migration and invasion were analyzed by the Transwell chamber method. Cell cycle analysis was performed by flow cytometry. Cell angiogenesis was assessed by HUVEC tube formation and human angiogenesis antibody array analysis. Proteins associated with proliferative and metastatic properties were evaluated by Western blotting.

KEY FINDINGS

Knockdown of FGFR2 suppressed cell growth and colony formation in CCA cells in association with G2/M cell cycle arrest and downregulation of STAT3, cyclin A and cyclin B1. Silencing FGFR2 enhanced the suppressive effect of gemcitabine (Gem) on cell migration and invasion. The combination of infigratinib, an FGFR inhibitor, and Gem, interrupted cell growth, migration, and invasion via downregulation of FGFR/AKT/mTOR pathways and the EMT-associated proteins vimentin and slug. Moreover, the combination also suppressed tube formation together with decreased expression of the proangiogenic factor VEGF.

SIGNIFICANCE

Inhibition of FGFRs by infigratinib enhanced the antitumor effect of Gem in CCA cells through downregulation of the FGFR/AKT/mTOR, FGFR/STAT3 and EMT signaling pathways.

GPR17 signaling activation by CHBC agonist induced cell death via modulation of MAPK pathway in glioblastoma

AIM

Glioblastoma multiforme (GBM) is the most common and aggressive primary adult brain tumor. GBM is characterized by a heterogeneous population of cells that are resistant to chemotherapy. Recently, we have synthesized CHBC, a novel indole derivative targeted to GBM biomarker G-protein-coupled receptor 17 and inhibitor of GBM cells. In this study, CHBC was further investigated to characterize the efficiency of this agonist at the molecular level and its underlying mechanism in GBM cell death induction.

MATERIALS AND METHODS

The effect of CHBC and TMZ was determined using time dependent inhibitor assay in glioblastoma cells, LN229 and SNB19. Drug induced cell cycle arrest was measured using PI staining followed by image analysis. The induction of apoptosis and mechanism of action of CHBC was studied using apoptosis, caspase 3/7 and mitochondrial membrane permeability assays. Modulation of the key genes involved in MAPK signaling pathway was also measured using immunoblotting array.

KEY FINDINGS

The inhibitory kinetic study has revealed that CHBC inhibited SNB19 and LN229 cell growth in a time-dependent manner. Furthermore, CHBC with the IC50 of 85 μM, mediated cell death through an apoptosis mechanism in both studied cell lines. The study also has revealed that CHBC targets GPR17 leading to the induction of apoptosis via the activation of Caspase 3/7 and dysfunction of mitochondrial membrane potential. In addition, CHBC treatment led to marked G2/M cell cycle arrest. The protein array has confirmed the anticancer effect of CHBC by the disruption of the mitogen-activated protein kinase pathway (MAPK).

SIGNIFICANCE

Taken together, these results demonstrated that CHBC induced G2/M cell cycle arrest and apoptosis by disrupting MAPK signaling in human glioblastoma cells. This study concludes that CHBC represent a class of compounds for treating glioblastoma.

BDE-209 induce spermatocytes arrest at early-pachytene stage during meiotic prophase I in mice

Deca-brominated diphenyl ether (BDE-209) is a common flame retardant utilized in electronic products, textiles, furniture, and upholstery materials. Environmental BDE-209 exposure results in spermatogenesis disorder, because of the characteristics of bioaccumulation, persistence, and probably toxicity. Meiotic prophase I is a crucial phase during spermatogenesis which is a key influential factor of normal sperm production. However, the effects of BDE-209 on meiotic prophase I during spermatogenesis are poorly understood. The present study aimed to evaluate whether BDE-209 exposure impairs meiotic prophase I during spermatogenesis of spermatocytes. We validated the effects of BDE-209 on alternations of meiotic prophase I in Balb/c male mice. Firstly, we analyzed sperm quality in cauda epididymis with decreasing sperm count, increasing abnormal sperm, and male reproductive dysfunction after exposure to BDE-209. Then, reactive oxygen species (ROS) and malondialdehyde (MDA) levels in testis and GC-2spd cells were significant increased after treated with BDE-209. Furthermore, we found that meiotic prophase I arrest at early-pachytene stage during spermatogenesis with increasing of DSBs damage and trimethylated histone H3 at lysine-4 (H3K4me3) in spermatocytes exposed to BDE-209. Finally, we conducted homologous recombination (HR) analyses to identify the progression of meiosis. The recombination markers, including DMC1 and RAD51, and crossover marker MLH1 were decreased during spermatogenesis after exposure to BDE-209. Collectively, our data indicated that BDE-209 has detrimental impacts on meiotic prophase I of spermatocytes in mice.

Artemisinin potentiates apoptosis and triggers cell cycle arrest to attenuate malignant growth of salivary gland tumor cells

One of the rare malignant tumors developing within the glands of the buccal cavity in human beings is salivary gland tumors (SGTs). The hallmark of SGTs is the fusion of nuclear factor IB (NFIB) and myeloblastosis (MYB) genes developed after the translocation of q22-23; p23-24. Although the aetiology of SGTs is not clear, however, the therapeutic modalities are surgical resection followed by the combination of chemotherapy and radiotherapy if a chance of recurrence seems to develop. Owing to have numerous side effects of chemotherapy, the drug development has been shifted to natural products with minimal side effects. One of the key phytochemical artemisinin derived from wormwood Artemisia annua exhibits various pharmacological activities against various in-vivo and in-vitro cellular models. Here, we evaluated the cytotoxic potential of artemisinin against A-253 cells with possible underlying cell death mechanisms. Our results showed that artemisinin reduces the proliferation of cells in a concentration-dependent manner and displays IC50 value in a range of 10.23, 14.21 μM, and 203.18 μM against A-253/HTB-41 and transformed salivary gland SMIE cells, respectively. Flow cytometry analysis demonstrated that artemisinin promotes a significant amount of apoptotic cellular population and triggers G0/G1 arrest of A-253 cells in a concentration-dependent manner. To verify the mechanism of cell death induced by artemisinin in A-253 cells, we found an increased level of Bax, Bim, Bad, Bak and reduced level of antiapoptotic protein Bcl-2, Bcl-XL with concomitant release of mitochondrial resident protein cytochrome c into the cytoplasm. Additionally, we found that artemisinin augments the production of reactive oxygen species which further leads to the activation of proapoptotic proteins PARP1, and caspase-3, in a concentration-dependent manner thereby triggering apoptosis. In conclusion, artemisinin exhibits promising anticancer therapeutic potential against A-253 cells and needs further validation of in-vitro results in preclinical models.

Activation of ATM/Chk2 by Zanthoxylum armatum DC extract induces DNA damage and G1/S phase arrest in BRL 3A cells

ETHNOPHARMACOLOGICAL RELEVANCE

Zanthoxylum armatum DC is a traditional medicinal plant. It is widely used in clinical treatment and disease prevention in China, India and other regions. Modern studies have reported the phytotoxicity, cytotoxicity and the animal toxicity of Zanthoxylum armatum DC, and the damage of genetic material has been observed in plants, but the detailed mechanism has not been explored. Besides, the toxicity of normal mammalian cells has not been evaluated.

AIM OF THE STUDY

To evaluate the effects and underlying mechanism of genetic material damage in BRL 3A cells induced by Zanthoxylum armatum DC.

MATERIALS AND METHODS

Ultra-High Performance Liquid Chromatography and Orbitrap High-Resolution Mass Spectrometry was used for identification of compounds in methanol extract of Zanthoxylum armatum DC. BRL 3A cells were incubated with different concentrations of methanol extract of Zanthoxylum armatum DC (24 h). The cytotoxicity of extract was assessed with cell viability, LDH release rate, and ROS production. The damage of genetic material was assessed with OTM value of comet cells, cell cycle and the expression levels of p-ATM, p- Chk2, Cdc25A, and CDK2.

RESULTS

Ultra-High Performance Liquid Chromatography and Orbitrap High-Resolution Mass Spectrometry investigation revealed the presence of compounds belonging to flavonoid, fatty acid and alkaloid groups. The viability of BRL 3A cells was reduced in a time-dose dependent manner treated by methanol extract of Zanthoxylum armatum DC. It increased LDH release rate and ROS production, activated the DNA double strand damage marker of γH2AX and produced comet cells. In addition, methanol extract of Zanthoxylum armatum DC caused ATM-mediated DNA damage, further phosphorylated Chk2, inhibited cell cycle related proteins, and arrested the G1/S cycle.

CONCLUSIONS

Methanol extract of Zanthoxylum armatum DC induces DNA damage and further leads G1/S cell cycle arrest by triggering oxidative stress in the BRL 3A cells. This study provides some useful evidences for its development as an antitumor drug via activation of ATM/Chk2.

Nanoplatform to Investigate Tumor-Initiating Cancer Stem Cells: Breaking the Diagnostic Barrier

Drug-resistant capacity in a small population of tumor-initiating cancer stem cells (tiCSCs) can be due to aberrant epigenetic changes. However, currently available conventional detection methods are inappropriate and cannot be applied to investigate the scarce population (tiCSCs). In addition, selective inhibitor drugs are shown to reverse epigenetic changes; however, each cancer type is discrete. Hence, it is essential to probe the resultant changes in tiCSCs even after therapy. Therefore, we have developed a multimode nanoplatform to investigate tiCSCs, detect epigenetic changes, and subsequently explore their transformation signals following drug therapy. We performed this by developing a surface-enhanced Raman scattering (SERS)-active nanoplatform integrated with n-dopant using an ultrafast laser ionization technique. The dopant functionalization enhances Raman scattering ability and permits label-free analysis of biomarkers in tiCSCs with the resolution down to the cellular level. Here, we investigated epigenetic biomarkers of tiCSCs in pancreatic and lung cancers. An extended study using inhibitor drugs demonstrates an unexpected increase of tiCSCs from lung cancer; this difference can be attributed to transformation changes in lung tiCSC. Thus, our work brings new insight into the differentiation abilities of CSCs upon epigenetic reversal, emphasizing unique perceptions in cancer treatment.

Sdy-1 Executes Antitumor Activity in HepG2 and HeLa Cancer Cells by Inhibiting the Wnt/β-Catenin Signaling Pathway

Demethylincisterol A₃ (Sdy-1), a highly degraded sterol that we previously isolated from Chinese mangrove Rhizophora mucronata endophytic Pestalotiopsis sp. HQD-6, exhibits potent antitumor activity towards a variety of cancer cells. In this study, we further verified that Sdy-1 effectively inhibited the proliferation and migration of human liver (HepG2) and cervical cancer (HeLa) cells in vitro and it can induce cell apoptosis and arrest the cell cycle in the G1-phase. Mechanistically, we demonstrated that Sdy-1 executes its function via inhibition of the Wnt/β-catenin signaling pathway. Sdy-1 may not inhibit the Wnt signaling pathway through the cascade reaction from upstream to downstream, but directly acts on β-catenin to reduce its transcription level, thereby reducing the level of β-catenin protein and further reducing the expression of downstream related proteins. The possible interaction between Sdy-1 and β-catenin protein was further confirmed by molecular docking studies. In the nude mouse xenograft model, Sdy-1 can also significantly inhibit tumor growth. These results indicated that Sdy-1 is an efficient inhibitor of the Wnt signaling pathway and is a promising antitumor candidate for therapeutic applications.

Anti-proliferative effects of the combination of Sulfamethoxazole and Quercetin via caspase3 and NFkB gene regulation: an in vitro and in vivo study

Combination therapy comprising natural polyphenols and anticancer drugs has been used to decrease the adverse effects and increase the effectiveness and antioxidant activities of the drugs. The antioxidant and anticancer effects of quercetin (Q), a nutritive polyphenol, have been observed both in vitro and in vivo. Likewise, the anticancer activity of sulfamethoxazole (S) has been demonstrated in vitro and in vivo. This study aimed to investigate the in vitro and in vivo anticancer effects of Q alone and in combination with S. The in vitro effects of S, Q, and S + Q on HCT-116, HepG2, MCF-7, and PC3 cell lines were examined. Additionally, the in vivo effects of these drugs were evaluated using Ehrlich ascites carcinoma (EAC) tumor-bearing mice. The in vitro data revealed the potent anticancer activity of S + Q through the induction of apoptosis and cell cycle arrest. The EAC-inoculated mice treated with S + Q presented with elevated SOD, GSH, CAT, and TAC levels and decreased malondialdehyde levels compared with the untreated EAC group, thus revealing the antioxidant and protective actions of S + Q against EAC cell invasion. Furthermore, the downregulation of NFkB and upregulation of the caspase3 gene in the EAC-inoculated mice treated with the S + Q indicated the induction of the apoptotic pathway and decrease in both cell proliferation and metastasis. In conclusion, the combination of S and Q might exert anticancer effects by inducing apoptosis and exhibiting selective toxicity against the cancer cells and thereby protecting the vital organs.

Aflatoxin B1 induces microglia cells apoptosis mediated by oxidative stress through NF-κB signaling pathway in mice spinal cords

Many studies have shown that aflatoxin B1 (AFB1) can cause cytotoxicity in numerous cells and organs induced by oxidative stress. However, the toxic effects and related mechanism of AFB1 on the microglia cells in the spinal cords have not been studied yet. Our results showed that AFB1 significantly reduced the number of microglia cells, increased the oxidants (malonaldehyde and hydrogen peroxide) but decreased the anti-oxidants (superoxide dismutase and total antioxidant capacity) in a dose dependent manner in mice spinal cords. In addition, AFB1 significantly increased the oxidative stress, promoted apoptosis and cell cycle arrest in G2-M phase, and activated NF-κB phosphorylation in BV2 microglia cells. However, the addition of active oxygen scavenger N-acetylcysteine can significantly reduce the ROS production, improve cell cycle arrest, reduce apoptosis, and the expression of phosphorylated NF-κB in BV2 microglia cells. These results indicate that AFB1 induces microglia cells apoptosis through oxidative stress by activating NF-κB signaling pathway.

Novel diosgenin-amino acid-benzoic acid mustard trihybrids exert antitumor effects via cell cycle arrest and apoptosis

In discovering new powerful antitumor agents, two series of novel diosgenin-amino acid-benzoic acid mustard trihybrids (7a-7 g and 12a-12 g) were designed and synthesized. The antiproliferative activities were tested against five human tumor cell lines and one normal cell line using CCK-8 assays. Among the trihybrids, 12e was the most promising compound, which inhibited T24 cells with IC₅₀ value of 6.96 μM, and was stronger than its parent compound diosgenin (IC₅₀ = 32.33 μM). In addition, 12e had weak cytotoxicity on the normal GES-1 cell line (IC₅₀ = 213.74 μM). Moreover, 12e could cause G2/M cell cycle arrest, increase the percentage of apoptosis, induce mitochondrial depolarization, and promote reactive oxygen species generation in T24 cells. Further studies on antitumor mechanism demonstrated that 12e triggered the intrinsic (mitochondrial) and extrinsic (death receptor) apoptotic pathways. More importantly, 12e could inhibit T24 cell proliferation in an in vivo zebrafish xenograft model. Therefore, 12e, as a novel trihybrid with potent cytotoxicity, might be applied as a promising skeleton for antitumor agents, which deserved further optimization.

Androgen receptor negatively regulates mitotic checkpoint signaling to induce docetaxel resistance in castration-resistant prostate cancer

BACKGROUND

Despite multiple treatment advances for castration-resistant prostate cancer (CRPC), there are currently no curative therapies and patients ultimately to succumb to the disease. Docetaxel (DTX) is the standard first-line chemotherapy for patients with metastatic CRPC; however, drug resistance is inevitable and often develops rapidly, leading to disease progression in nearly all patients. In contrast, when DTX is deployed with androgen deprivation therapy in castration-sensitive disease, more durable responses and improved outcomes are observed, suggesting that aberrant androgen receptor (AR) signaling accelerates DTX resistance in CRPC. In this study, we demonstrate that AR dysregulates the mitotic checkpoint, a critical pathway involved in the anticancer action of DTX.

METHODS

Androgen-dependent and independent cell lines were used to evaluate the role of AR in DTX resistance. Impact of drug treatment on cell viability, survival, and cell-cycle distribution were determined by plate-based viability assay, clonogenic assay, and cell-cycle analysis by flow cytometry, respectively. Mitotic checkpoint kinase signal transduction and apoptosis activation was evaluated by Western blotting. Pathway gene expression analysis was evaluated by RT-PCR. A Bliss independence model was used to calculate synergy scores for drug combination studies.

RESULTS

Activation of AR in hormone-sensitive cells induces a rescue phenotype by increasing cell viability and survival and attenuating G2/M arrest in response to DTX. Analysis of mitotic checkpoint signaling shows that AR negatively regulates spindle checkpoint signaling, resulting in premature mitotic progression and evasion of apoptosis. This phenotype is characteristic of mitotic slippage and is also observed in CRPC cell lines where we demonstrate involvement of AR splice variant AR-v7 in dysregulation of checkpoint signaling. Our findings suggest that DTX resistance is mediated through mechanisms that drive premature mitotic exit. Using pharmacologic inhibitors of anaphase-promoting complex/cyclosome and polo-like kinase 1, we show that blocking mitotic exit induces mitotic arrest, apoptosis, and synergistically inhibits cell survival in combination with DTX.

CONCLUSION

Our results suggest that targeting the mechanisms of dysregulated mitotic checkpoint signaling in AR-reactivated tumors has significant clinical potential to extend treatment benefit with DTX and improve outcomes in patients with lethal prostate cancer.

Anti-tumor effects of vitamin D in glioblastoma: mechanism and therapeutic implications

Glioma is the most prevalent primary brain tumor in adults among which glioblastoma is the most malignant and lethal subtype. Its common resistance to conventional chemotherapeutics calls for the development of alternative or concomitant treatment. Taking advantage of its endocrine function as a neurosteroid, vitamin D has become a target of interest to be used in conjunction with different chemotherapies. In this article, we review the mechanisms through which vitamin D and its analogs induce anti-tumor activity in glioblastoma, and the practical issues relevant to their potential application based on in vitro and in vivo studies. Vitamin D has largely been reported to promote cell cycle arrest and induce cell death to suppress tumor growth in glioblastoma. Glioblastoma cells treated with vitamin D have also shown reduced migratory and invasive phenotypes, and reduced stemness. It is worth noting that vitamin D analogs are able to produce similar inhibitory actions without causing adverse effects such as hypercalcemia in vivo. Upregulation of vitamin D receptors by vitamin D and its analogs may also play a role in enhancing its anti-tumor activity. Based on current findings and taking into consideration its potential cancer-protective effects, the clinical application of vitamin D in glioblastoma treatment and prevention will be discussed. With some study findings subject to controversy, further investigation is warranted to elucidate the mechanism of action of vitamin D and to evaluate relevant issues regarding its treatment efficacy and potential clinical application.

Alkaloid-rich fraction of Ervatamia coronaria sensitizes colorectal cancer through modulating AMPK and mTOR signalling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Ervatamia coronaria, a popular garden plant in India and some other parts of the world is known traditionally for its anti-inflammatory and anti-cancer properties. The molecular bases of these functions remain poorly understood.

AIM OF THE STUDY

Efficacies of the existing therapies for colorectal cancer (CRC) are limited by their life-threatening side effects and unaffordability. Therefore, identifying a safer, efficient, and affordable therapeutic is urgent. We studied the anti-CRC activity of an alkaloid-rich fraction of E. coronaria leaf extracts (AFE) and associated underlying mechanism.

MATERIALS AND METHODS

Activity guided solvant fractionation was adopted to identify the activity in AFE. Different cell lines, and tumor grown in syngeneic mice were used to understand the anti-CRC effect. Methodologies such as LCMS, MTT, RT-qPCR, immunoblot, immunohistochemistry were employed to understand the molecular basis of its activity.

RESULTS

We showed that AFE, which carries about six major compounds, is highly toxic to colorectal cancer (CRC) cells. AFE induced cell cycle arrest at G1 phase and p21 and p27 genes, while those of CDK2, CDK-4, cyclin-D, and cyclin-E genes were downregulated in HCT116 cells. It predominantly induced apoptosis in HCT116p53+/+ cells while the HCT116p53-/- cells under the same treatment condition died by autophagy. Notably, AFE induced upregulation of AMPK phosphorylation, and inhibition of both of the mTOR complexes as indicated by inhibition of phosphorylation of S6K1, 4EBP1, and AKT. Furthermore, AFE inhibited mTOR-driven conversion of cells from reversible cell cycle arrest to senescence (geroconversion) as well as ERK activity. AFE activity was independent of ROS produced, and did not primarily target the cellular DNA or cytoskeleton. AFE also efficiently regressed CT26-derived solid tumor in Balb/c mice acting alone or in synergy with 5FU through inducing autophagy as a major mechanism of action as indicated by upregulation of Beclin 1 and phospho-AMPK, and inhibition of phospho-S6K1 levels in the tumor tissue lysates.

CONCLUSION

AFE induced CRC death through activation of both apoptotic and autophagy pathways without affecting the normal cells. This study provided a logical basis for consideration of AFE in future therapy regimen to overcome the limitations associated with existing anti-CRC chemotherapy.

Chemical Space Expansion of Flavonoids: Induction of Mitotic Inhibition by Replacing Ring B with a 10π-Electron System, Benzo[b]thiophene

Natural products, which are enzymatically biosynthesized, have a broad range of biological activities. In particular, many flavonoids are known to contribute to human health with low toxicity. We previously reported that novel benzo[b]thiophenyl (BT) flavones with a 10π-electron BT ring B replacing the usual 6π-electron phenyl ring showed potent antiproliferative activity against human tumor cell lines. Interestingly, the activity profiles against cell cycle progression of the BT-flavones totally changed depending on the combination of substituents at the C-3 and C-5 positions. This finding encouraged an extension of these studies on the impact of BT to related flavonoids, such as chalcones, isoflavones, and aurones. Accordingly, 10 isoflavones, 29 chalcones, and four aurones were synthesized and evaluated for antiproliferative activity against five human tumor cell lines including a multi-drug-resistant cell line. Among these compounds, BT-isoflavone 7, BT-chalcones 48, 52, 57, 66, and 77, and BT-aurone 80 displayed significant antiproliferative effects against all tested tumor cell lines. The structure-antiproliferative activity relationships clearly demonstrated the importance of BT instead of phenyl as ring B for the isoflavone and chalcones, but not the aurones. Flow cytometry and immunocytochemical studies demonstrated that the active BT-flavonoids led to cell cycle arrest at the prometaphase by induction of multipolar spindle formation. The present studies should contribute greatly to the synthesis and functional analysis of biologically active flavonoid derivatives for chemical space expansion.

Alkaloids and Colon Cancer: Molecular Mechanisms and Therapeutic Implications for Cell Cycle Arrest

Cancer is the second most fatal disease worldwide, with colon cancer being the third most prevalent and fatal form of cancer in several Western countries. The risk of acquisition of resistance to chemotherapy remains a significant hurdle in the management of various types of cancer, especially colon cancer. Therefore, it is essential to develop alternative treatment modalities. Naturally occurring alkaloids have been shown to regulate various mechanistic pathways linked to cell proliferation, cell cycle, and metastasis. This review aims to shed light on the potential of alkaloids as anti-colon-cancer chemotherapy agents that can modulate or arrest the cell cycle. Preclinical investigated alkaloids have shown anti-colon cancer activities and inhibition of cancer cell proliferation via cell cycle arrest at different stages, suggesting that alkaloids may have the potential to act as anticancer molecules.

Rhenium Perrhenate (188ReO4) Induced Apoptosis and Reduced Cancerous Phenotype in Liver Cancer Cells

Recurrence in hepatocellular carcinoma (HCC) after conventional treatments is a crucial challenge. Despite the promising progress in advanced targeted therapies, HCC is the fourth leading cause of cancer death worldwide. Radionuclide therapy can potentially be a practical targeted approach to address this concern. Rhenium-188 (188Re) is a β-emitting radionuclide used in the clinic to induce apoptosis and inhibit cell proliferation. Although adherent cell cultures are efficient and reliable, appropriate cell-cell and cell-extracellular matrix (ECM) contact is still lacking. Thus, we herein aimed to assess 188Re as a potential therapeutic component for HCC in 2D and 3D models. The death rate in treated Huh7 and HepG2 lines was significantly higher than in untreated control groups using viability assay. After treatment with 188ReO4, Annexin/PI data indicated considerable apoptosis induction in HepG2 cells after 48 h but not Huh7 cells. Quantitative RT-PCR and western blotting data also showed increased apoptosis in response to 188ReO4 treatment. In Huh7 cells, exposure to an effective dose of 188ReO4 led to cell cycle arrest in the G2 phase. Moreover, colony formation assay confirmed post-exposure growth suppression in Huh7 and HepG2 cells. Then, the immunostaining displayed proliferation inhibition in the 188ReO4-treated cells on 3D scaffolds of liver ECM. The PI3-AKT signaling pathway was activated in 3D culture but not in 2D culture. In nude mice, Huh7 cells treated with an effective dose of 188ReO4 lost their tumor formation ability compared to the control group. These findings suggest that 188ReO4 can be a potential new therapeutic agent against HCC through induction of apoptosis and cell cycle arrest and inhibition of tumor formation. This approach can be effectively combined with antibodies and peptides for more selective and personalized therapy.

FGFC1 Exhibits Anti-Cancer Activity via Inhibiting NF-κB Signaling Pathway in EGFR-Mutant NSCLC Cells

FGFC1, an active compound isolated from the culture of marine fungi Stachybotrys longispora FG216, elicits fibrinolytic, anti-oxidative, and anti-inflammatory activity. We have previously reported that FGFC1 inhibited the proliferation, migration, and invasion of the non-small cell lung cancer (NSCLC) cells in vitro. However, the precise mechanisms of FGFC1 on NSCLC and its anti-cancer activity in vivo remains unclear. Hence, this study was focused to investigate the effects and regulatory mechanisms of FGFC1 on two NSCLC cell lines, EGFR-mutant PC9 (ex19del) and EGFR wild-type H1299. Results suggested that FGFC1 significantly inhibited proliferation, colony formation, as well as triggered G0/G1 arrest and apoptosis of PC9 cells in a dose- and time-dependent manner, but no obvious inhibitory effects were observed in H1299 cells. Subsequently, transcriptome analysis revealed that FGFC1 significantly down-regulated 28 genes related to the NF-κB pathway, including IL-6, TNF-α, and ICAM-1 in the PC9 cells. We further confirmed that FGFC1 decreased the expression of protein p-IKKα/β, p-p65, p-IκB, IL-6, and TNF-α. Moreover, NF-κB inhibitor PDTC could strengthen the effects of FGFC1 on the expression of CDK4, Cyclin D1, cleaved-PARP-1, and cleaved-caspase-3 proteins, suggesting that the NF-κB pathway plays a major role in FGFC1-induced cell cycle arrest and apoptosis. Correspondingly, the nuclear translocation of p-p65 was also suppressed by FGFC1 in PC9 cells. Finally, the intraperitoneal injection of FGFC1 remarkably inhibited PC9 xenograft growth and decreased the expression of Ki-67, p-p65, IL-6, and TNF-α in tumors. Our results indicated that FGFC1 exerted anti-cancer activity in PC9 cells via inhibiting the NF-κB signaling pathway, providing a possibility for FGFC1 to be used as a lead compound for the treatment of NSCLC in the future.

Curcin C inhibit osteosarcoma cell line U2OS proliferation by ROS induced apoptosis, autophagy and cell cycle arrest through activating JNK signal pathway

Osteosarcoma is a kind of primary bone malignant tumors. Its cure rate has been stagnant in the past decade years. Curcin C belongs to type I ribosome inactivating proteins, extracted from the cotyledons of post-germinated Jatropha curcas seeds. It can inhibit the proliferation of several tumor lines including U2OS cells with extraordinary efficiency. The treated U2OS cells were arrested in both S and G2/M phase, showed typical apoptosis morphological characteristic, formed autophagosomes and increase the ratio of LC3II to LC3I. Meanwhile, the level of ROS in the treated cells was found increasing significantly, with the change of mitochondrial membrane potential and decreased antioxidant enzyme activities. The application of ROS scavenger NAC not only significantly inhibited the toxicity of Curcin C but also prevented the happen of apoptosis and autophagy to some extent. These results suggested that Curcin C may function through ROS pathway. In addition, the Curcin C treatment could activate JNK and inhibit ERK signal pathway. Sp600125, an inhibitor of JNK signaling pathway, can prevent subsequent apoptosis and autophagy events, suggesting that JNK pathway was at least one of the pathways of Curcin C action. Moreover, the relevant including antagonistic among autophagy, apoptosis and cell cycle arresting induced by Curcin C also was found. In summary, it can be speculated that Curcin C may induce S, G2/M phase arrest, apoptosis and autophagy of human osteosarcoma U2OS cells through activating JNK signal pathway and blocking ERK signal pathway by promoting ROS accumulation in cell, thus finally reflected in the effect of inhibiting tumor cell proliferation.

Olive Mill Wastewater Inhibits Growth and Proliferation of Cisplatin- and Gemcitabine-Resistant Bladder Cancer Cells In Vitro by Down-Regulating the Akt/mTOR-Signaling Pathway

Bladder cancer patients whose tumors develop resistance to cisplatin-based chemotherapy often turn to natural, plant-derived products. Beneficial effects have been particularly ascribed to polyphenols, although their therapeutic relevance when resistance has developed is not clear. The present study evaluated the anti-tumor potential of polyphenol-rich olive mill wastewater (OMWW) on chemo-sensitive and cisplatin- and gemcitabine-resistant T24, RT112, and TCCSUP bladder cancer cells in vitro. The cells were treated with different dilutions of OMWW, and tumor growth and clone formation were evaluated. Possible mechanisms of action were investigated by evaluating cell cycle phases and cell cycle-regulating proteins. OMWW profoundly inhibited the growth and proliferation of chemo-sensitive as well as gemcitabine- and cisplatin-resistant bladder cancer cells. Depending on the cell line and on gemcitabine- or cisplatin-resistance, OMWW induced cell cycle arrest at different phases. These differing phase arrests were accompanied by differing alterations in the CDK-cyclin axis. Considerable suppression of the Akt-mTOR pathway by OMWW was observed in all three cell lines. Since OMWW blocks the cell cycle through the manipulation of the cyclin-CDK axis and the deactivation of Akt-mTOR signaling, OMWW could become relevant in supporting bladder cancer therapy.

Suppressing Effect of Na+/Ca2+ Exchanger (NCX) Inhibitors on the Growth of Melanoma Cells

The role of calcium ion (Ca²⁺) signaling in tumorigenicity has received increasing attention in melanoma research. Previous Ca²⁺ signaling studies focused on Ca²⁺ entry routes, but rarely explored the role of Ca²⁺ extrusion. Functioning of the Na⁺/Ca²⁺ exchanger (NCX) on the plasma membrane is the major way of Ca²⁺ extrusion, but very few associations between NCX and melanoma have been reported. Here, we explored whether pharmacological modulation of the NCX could suppress melanoma and promise new therapeutic strategies. Methods included cell viability assay, Ca²⁺ imaging, immunoblotting, and cell death analysis. The NCX inhibitors SN-6 and YM-244769 were used to selectively block reverse operation of the NCX. Bepridil, KB-R7943, and CB-DMB blocked either reverse or forward NCX operation. We found that blocking the reverse NCX with SN-6 or YM-244769 (5–100 μM) did not affect melanoma cells or increase cytosolic Ca²⁺. Bepridil, KB-R7943, and CB-DMB all significantly suppressed melanoma cells with IC₅₀ values of 3–20 μM. Bepridil and KB-R7943 elevated intracellular Ca²⁺ level of melanoma. Bepridil-induced melanoma cell death came from cell cycle arrest and enhanced apoptosis, which were all attenuated by the Ca²⁺ chelator BAPTA-AM. As compared with melanoma, normal melanocytes had lower NCX1 expression and were less sensitive to the cytotoxicity of bepridil. In conclusion, blockade of the forward but not the reverse NCX leads to Ca²⁺-related cell death in melanoma and the NCX is a potential drug target for cancer therapy.

Reprogramming of nucleotide metabolism by interferon confers dependence on the replication stress response pathway in pancreatic cancer cells

We determine that type I interferon (IFN) response biomarkers are enriched in a subset of pancreatic ductal adenocarcinoma (PDAC) tumors; however, actionable vulnerabilities associated with IFN signaling have not been systematically defined. Integration of a phosphoproteomic analysis and a chemical genomics synergy screen reveals that IFN activates the replication stress response kinase ataxia telangiectasia and Rad3-related protein (ATR) in PDAC cells and sensitizes them to ATR inhibitors. IFN triggers cell-cycle arrest in S-phase, which is accompanied by nucleotide pool insufficiency and nucleoside efflux. In combination with IFN, ATR inhibitors induce lethal DNA damage and downregulate nucleotide biosynthesis. ATR inhibition limits the growth of PDAC tumors in which IFN signaling is driven by stimulator of interferon genes (STING). These results identify a cross talk between IFN, DNA replication stress response networks, and nucleotide metabolism while providing the rationale for targeted therapeutic interventions that leverage IFN signaling in tumors.

Growth Inhibition and Apoptotic Effect of Pine Extract and Abietic Acid on MCF-7 Breast Cancer Cells via Alteration of Multiple Gene Expressions Using In Vitro Approach

In vitro anti-proliferative activity of Pinus palustris extract and its purified abietic acid was assessed against different human cancer cell lines (HepG-2, MCF-7 and HCT-116) compared to normal WI-38 cell line. Abietic acid showed more promising IC50 values against MCF-7 cells than pine extract (0.06 µg/mL and 0.11 µM, respectively), with insignificant cytotoxicity toward normal fibroblast WI-38 cells. Abietic acid triggered both G2/M cell arrest and subG0-G1 subpopulation in MCF-7, compared to SubG0-G1 subpopulation arrest only for the extract. It also induced overexpression of key apoptotic genes (Fas, FasL, Casp3, Casp8, Cyt-C and Bax) and downregulation of both proliferation (VEGF, IGFR1, TGF-β) and oncogenic (C-myc and NF-κB) genes. Additionally, abietic acid induced overexpression of cytochrome-C protein. Furthermore, it increased levels of total antioxidants to diminish carcinogenesis and chemotherapy resistance. P. palustris is a valuable source of active abietic acid, an antiproliferative agent to MCF-7 cells through induction of apoptosis with promising future anticancer agency in breast cancer therapy.

Rutaecarpine Prevents High Glucose-Induced Endothelial Cell Senescence Through Transient Receptor Potential Vanilloid Subtype 1/ SIRT1 Pathway

ABSTRACT

SIRT1 functions as a longevity factor to counteract vascular aging induced by high glucose. Our previous study revealed that rutaecarpine, the natural agonist of transient receptor potential vanilloid subtype 1 (TRPV1), prevented high glucose-induced endothelial dysfunction. The present study aims to evaluate the effects of rutaecarpine on endothelial cell senescence induced by high glucose, and focus on the regulatory effect on SIRT1 expression. In cultured human umbilical vein endothelial cell (HUVEC), exposure to 33 mM high glucose for 72 hours induced cellular senescence, demonstrated as cell cycle arrest at G0/G1 phase, decreased cell viability, and increased number of senescence-associated β-galactosidase positive senescence cells and ROS production, which were effectively attenuated by treatment with rutaecarpine (0.3, 1, and 3 μM). Furthermore, rutaecarpine upregulated longevity protein SIRT1 expression in HUVECs, accompanied by decreased level of senescence marker p21. In addition, rutaecarpine increased intracellular calcium level in HUVECs, and pretreatment with TRPV1 antagonist capsazepine, intracellular Ca2+ chelator BAPTA-AM or CaM antagonist W-7 abolished the effects of rutaecarpine on SIRT1 expression. In summary, this study shows that rutaecarpine upregulates SIRT1 expression and prevents high glucose-induced endothelial cell senescence, which is related to activation of TRPV1/[Ca2+]i/CaM signal pathway. Our findings provide evidence that rutaecarpine may be a promising candidate with a novel mechanism in prevention vascular aging in diabetes.

Mutant p53 reactivator SLMP53-2 hinders ultraviolet B radiation-induced skin carcinogenesis

The growing incidence of skin cancer (SC) has prompted the search for additional preventive strategies to counteract this global health concern. Mutant p53 (mutp53), particularly with ultraviolet radiation (UVR) signature, has emerged as a promising target for SC prevention based on its key role in skin carcinogenesis. Herein, the preventive activity of our previously disclosed mutp53 reactivator SLMP53-2 against UVR-induced SC was investigated. The pre-treatment of keratinocyte HaCaT cells with SLMP53-2, before UVB exposure, depleted mutp53 protein levels with restoration of wild-type-like p53 DNA-binding ability and subsequent transcriptional activity. SLMP53-2 increased cell survival by promoting G1-phase cell cycle arrest, while reducing UVB-induced apoptosis through inhibition of c-Jun N-terminal kinase (JNK) activity. SLMP53-2 also protected cells from reactive oxygen species and oxidative damage induced by UVB. Moreover, it enhanced DNA repair through upregulation of nucleotide excision repair pathway and depletion of UVB-induced DNA damage, as evidenced by a reduction of DNA in comet tails, γH2AX staining and cyclobutane pyrimidine dimers (CPD) levels. SLMP53-2 further suppressed UVB-induced inflammation by inhibiting the nuclear translocation and DNA-binding ability of NF-κB, and promoted the expression of key players involved in keratinocytes differentiation. Consistently, the topical application of SLMP53-2 in mice skin, prior to UVB irradiation, reduced cell death and DNA damage. It also decreased the expression of inflammatory-related proteins and promoted cell differentiation, in UVB-exposed mice skin. Notably, SLMP53-2 did not show signs of skin toxicity for cumulative topical use. Overall, these results support a promising protective activity of SLMP53-2 against UVB-induced SC.

NF-κB suppression synergizes with E7386, an inhibitor of CBP/β-catenin interaction, to block proliferation of patient-derived colon cancer spheroids

Dysregulated activation of the WNT/β-catenin signaling pathway is essential for the initiation and development of various cancers. E7386, a small-molecule compound, attenuates WNT signaling by blocking the interaction between β-catenin and CREB-binding protein (CBP); hence, it is regarded as a therapeutic candidate for cancers with activated WNT signaling. In the present study, we evaluated the biological characteristics associated with E7386 sensitivity by using a panel of patient-derived colon cancer spheroids. An integrative approach that combined E7386 sensitivity and gene expression profiles revealed that the resistance of the cancer spheroids to E7386 was associated with the activation of the NF-κB pathway. NF-κB pathway inhibitors acted synergistically with E7386 to block proliferation and induce cell cycle arrest in E7386-resistant spheroids. These findings suggest a possibility that a combination of E7386 and NF-κB inhibition may effectively block the proliferation of a subset of colon cancer cells.

FDI-6 and olaparib synergistically inhibit the growth of pancreatic cancer by repressing BUB1, BRCA1 and CDC25A signaling pathways

Inducing homologous recombination (HR) deficiency is a promising strategy to broaden the indication of PARP1/2 inhibitors in pancreatic cancer treatment. In addition to inhibition kinases, repression of the transcriptional function of FOXM1 has been reported to inhibit HR-mediated DNA repair. We found that FOXM1 inhibitor FDI-6 and PARP1/2 inhibitor Olaparib synergistically inhibited the malignant growth of pancreatic cancer cells in vitro and in vivo. The results of bioinformatic analysis and mechanistic study showed that FOXM1 directly interacted with PARP1. Olaparib induced the feedback overexpression of PARP1/2, FOXM1, CDC25A, CCND1, CDK1, CCNA2, CCNB1, CDC25B, BRCA1/2 and Rad51 to promote the acceleration of cell mitosis and recovery of DNA repair, which caused the generation of adaptive resistance. FDI-6 reversed Olaparib-induced adaptive resistance and inhibited cell cycle progression and DNA damage repair by repressing the expression of FOXM1, PARP1/2, BUB1, CDC25A, BRCA1 and other genes-involved in cell cycle control and DNA damage repair. We believe that targeting FOXM1 and PARP1/2 is a promising combination therapy for pancreatic cancer without HR deficiency.

Palmitate Enhances the Efficacy of Cisplatin and Doxorubicin against Human Endometrial Carcinoma Cells

Endometrial cancer is the most common gynecological cancer worldwide. At present there is no effective screening test for its early detection and no curative treatment for women with advanced-stage or recurrent disease. Overexpression of fatty acid synthase is a common molecular feature of a subgroup of sex steroid-related cancers associated with poor prognoses, including endometrial cancers. Disruption of this fatty acid synthesis leads to cell apoptosis, making it a potential therapeutic target. The saturated fatty acid palmitate reportedly induces lipotoxicity and cell death by inducing oxidative stress in many cell types. Here, we explored the effects of palmitate combined with doxorubicin or cisplatin in the HEC-1-A and RL95-2 human endometrial cancer cell lines. The results showed that physiological concentrations of exogenous palmitate significantly increased cell cycle arrest, DNA damage, autophagy, and apoptosis in both RL95-2 and HEC-1-A cells. It also increased the chemosensitivity of both cell types. Notably, we did not observe that palmitate lipotoxicity reflected increased levels of reactive oxygen species, suggesting palmitate acts via a different mechanism in endometrial cancer. This study thus provides a potential therapeutic strategy in which palmitate is used as an adjuvant in the treatment of endometrial cancer.

The Influence of Angiotensin Peptides on Survival and Motility of Human High-Grade Serous Ovarian Cancer Cells in Serum Starvation Conditions

High-grade serous ovarian carcinoma (HGSOC) is the most frequent and malignant form of ovarian cancer. A local renin-angiotensin system (RAS) has been found in the ovary, and changes in selected components of this system were observed in pathological states and also in ovarian cancer. In the present study, we examined the effect of three peptides, Ang-(1-7), Ang-(1-9) and Ang-(3-7), on proliferation and motility of the OVPA8 cell line, a new well-defined and preclinical model of HGSOC. We confirmed the presence of mRNA for all angiotensin receptors in the tested cells. Furthermore, our findings indicate that all tested angiotensin peptides increased the metabolic serum in the medium by activation of cell defense mechanisms such as nuclear factor kappaB signaling pathway andapoptosis. Moreover, tested angiotensin peptides intensified serum starvation-induced cell cycle arrest at the G0/G1 phase. In the case of Ang-(3-7), a significant decrease in the number of Ki67 positive cells (Ki67+) and reduced percentage of activated ERK1/2 levels in ovarian cancer cells were additionally reported. The angiotensin-induced effect of the accumulation of cells in the G0/G1 phase was not observed in OVPA8 cells growing on the medium with 10% FBS. Moreover, in the case of Ang-(3-7), the tendency was quite the opposite. Ang-(1-7) but not Ang-(1-9) or Ang-(3-7) increased the mobility of reluctant-to-migrate OVAP8 cells cultured in the serum-free medium. In any cases, the changes in the expression of VIM and HIF1A gene, associated with epithelial-mesenchymal transition (EMT), were not observed. In conclusion, we speculate that the adaptation to starvation in nutrient-deprived tumors can be modulated by peptides from the renin-angiotensin system. The influence of angiotensin peptides on cancer cells is highly dependent on the availability of growth factors and nutrients.

Aroylhydrazone Diorganotin Complexes Causes DNA Damage and Apoptotic Cell Death: From Chemical Synthesis to Biochemical Effects

Under microwave irradiation, eighteen new aroylhydrazone diorganotin complexes (1a–9b) were produced through the reaction of aroylhydrazine, 2-ketobutyric acid, and the corresponding diorganotin. Fourier transform infrared spectroscopy, ¹H, ¹³C, and ¹¹⁹Sn nuclear magnetic resonance spectroscopies, high-resolution mass spectroscopy, X-ray crystallography, and thermogravimetric analysis (TGA) were performed to characterize the complexes. The in vitro anticancer activity for complexes were assessed using a CCK-8 assay on human cancer cells of HepG2, NCI-H460, and MCF-7. Complex 4b revealed more intensive anticancer activity against MCF-7 cells than the other complexes and cisplatin. Flow cytometry analysis and transmission electron microscope observation demonstrated that complex 4b mediated cell apoptosis of MCF-7 cells and arrested cell cycle in S phase. Western blotting analysis showed that 4b induced DNA damage in MCF-7 cells and led to apoptosis by the ATM-CHK2-p53 pathway. The single cell gel electrophoreses assay results showed that 4b induced DNA damage. The DNA binding activity of 4b was studied by UV–Visible absorption spectrometry, fluorescence competitive, viscosity measurements, gel electrophoresis, and molecular docking, and the results show that 4b can be well embedded in the groove and cleave DNA.

Senotherapeutic-like effect of Silybum marianum flower extract revealed on human skin cells

Cellular senescence causes irreversible growth arrest of cells. Prolonged accumulation of senescent cells in tissues leads to increased detrimental effects due to senescence associated secretory phenotype (SASP). Recent findings suggest that elimination of senescent cells has a beneficial effect on organismal aging and lifespan. In this study, using a validated replicative senescent human dermal fibroblasts (HDFs) model, we showed that elimination of senescent cells is possible through the activation of an apoptotic mechanism. We have shown in this replicative senescence model, that cell senescence is associated with DNA damage and cell cycle arrest (p21, p53 markers). We have shown that Silybum marianum flower extract (SMFE) is a safe and selective senolytic agent targeting only senescent cells. The elimination of the cells is induced through the activation of apoptotic pathway confirmed by annexin V/propidium iodide and caspase-3/PARP staining. Moreover, SMFE suppresses the expression of SASP factors such as IL-6 and MMP-1 in senescent HDFs. In a co-culture model of senescent and young fibroblasts, we demonstrated that senescent cells impaired the proliferative capacities of young cells. Interestingly, when the co-culture is treated with SMFE, the cell proliferation rate of young cells is increased due to the decrease of the senescent burden. Moreover, we demonstrated in vitro that senescent fibroblasts trigger senescent process in normal keratinocytes through a paracrine effect. Indeed, the conditioned medium of senescent HDFs treated with SMFE reduced the level of senescence-associated beta-galactosidase (SA-β-Gal), p16INK4A and SASP factors in keratinocytes compared with CM of senescent HDFs. These results indicate that SMFE can prevent premature aging due to senescence and even reprograms aged skin. Indeed, thanks to its senolytic and senomorphic properties SMFE is a candidate for anti-senescence strategies.

Modulated Electro-Hyperthermia Supports the Effect of Gemcitabine Both in Sensitive and Resistant Pancreas Adenocarcinoma Cell Lines

The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is frequently associated to high treatment resistance. Gemcitabine (GEM) alone or in combination is the most used chemotherapy for unresecable PDACs. Here we studied whether modulated electro-hyperthermia (mEHT), a non-invasive complementary treatment, can support the effect of GEM on PDAC cells in vitro. The LD20 for the GEM-resistant Panc1 cells proved to be 200× higher than for the drug-sensitive Capan1. The mEHT alone caused significant apoptosis in Capan1 cultures as confirmed by the elevated SubG1 phase cell fraction and increased number of cleaved Caspase-3 positive cells 48 h after treatment, with an additive effect when GEM was used after hyperthermia. These were accompanied by reduced number of G1, S, and G2/M phase cells and elevated expression of the cyclin-dependent kinase inhibitor p21waf1 protein. In GEM-resistant Panc1 cells, an initial apoptosis was detected by flow cytometry 24 h after mEHT ± GEM treatment, which however diminished by 48 h at persistent number of cleaved Caspase-3 positive tumor cells. Though GEM monotherapy reduced the number of tumor progenitor colonies in Capan1 cell line, an additive colony inhibitory effect of mEHT was observed after mEHT + GEM treatment. The heat shock induced Hsp27 and Hsp70 proteins, which are known to sensitize PDAC cells to GEM were upregulated in both Capan1 and Panc1 cells 24 h after mEHT treatment. The level of E-Cadherin, a cell adhesion molecule, increased in Capan1 cells after mEHT + GEM treatment. In conclusion, in GEM-sensitive PDAC cells mEHT treatment alone induced cell death and cell cycle inhibition and improved GEM efficiency in combination, which effects were milder and short-term up to 24 h in the GEM-resistant Panc1 cells. Our data further support the inclusion of hyperthermia, in particular of mEHT, into the traditional oncotherapy regimens of PDAC.

Silencing of Pyruvate Kinase M2 via a Metal-Organic Framework Based Theranostic Gene Nanomedicine for Triple-Negative Breast Cancer Therapy

Triple-negative breast cancer (TNBC) is typically associated with poor prognosis due to its only partial response to chemotherapy and lack of clinically established targeted therapies coupled with an aggressive disease course. Aerobic glycolysis is a hallmark of reprogrammed metabolic activity in cancer cells, which can be repressed by small-interfering RNA (siRNA). However, the lack of effective carriers to deliver vulnerable siRNA restricts the clinical potentials of glycolysis-based gene therapy for TNBC. Herein, we develop a tumor-targeted, biomimetic manganese dioxide (MnO₂)-shrouded metal-organic framework (MOF) based nanomedicine to deliver siRNA against pyruvate kinase muscle isozyme M2 (siPKM2), wherein PKM2 is a rate-limiting enzyme in glycolysis, to inhibit the reprogrammed glycolysis of TNBC. This MOF-based genetic nanomedicine shows excellent monodispersity and stability and protects siPKM2 against degradation by nucleases. The nanomedicine not only substantially blocks the glycolytic pathway but also improves intracellular hypoxia in TNBC cells, with a resultant O₂-enhanced anticancer effect. In the mice orthotopic TNBC model, the nanomedicine shows a remarkable therapeutic effect. Meanwhile, the Mn²⁺ ions released from acid microenvironment-responsive MnO₂ enable in vivo monitoring of the therapeutic process with magnetic resonance imaging (MRI). Our study shows great promise with this MRI-visible MOF-based nanomedicine for treating TNBC by inhibition of glycolysis via the RNA interference.

Stattic sensitizes osteosarcoma cells to epidermal growth factor receptor inhibitors via blocking the interleukin 6-induced STAT3 pathway

Osteosarcoma (OS), the most common malignant bone tumor with high metastatic potential, frequently affects children and adolescents. Epidermal growth factor receptor (EGFR)-targeted tyrosine kinase inhibitors exhibit encouraging anti-tumor activity for patients with solid tumors, whereas their effects on OS remain controversial. In the present study, we aimed to elucidate the anti-tumor activity of gefitinib for OS, as well as to explore the underlying mechanisms. Gefitinib inhibits cell viability, tumor growth, cell migration, and invasion and promotes cell apoptosis and G1 cycle arrest in OS at a relatively high concentration via suppressing the PI3K/Akt and ERK pathways. However, gefitinib treatment results in the feedback activation of signal transducer and activator of transcription 3 (STAT3) induced by interleukin 6 (IL-6) secretion. Combined treatment with gefitinib and stattic, an inhibitor for STAT3 phosphorylation, engenders more evident inhibitory effects on cell proliferation, migration, and invasion and promotive effects on cell apoptosis and G1 phase arrest in OS, compared with the single exposure to gefitinib or stattic. Western blot analysis demonstrates that stattic treatment in gefitinib-treated OS abrogates the IL-6-induced STAT3 activation and subsequently further restrains the activities of EGFR, Akt, and ERK pathways in tumor cells. This study confirms that the EGFR inhibitor of gefitinib has moderate anti-tumor effects on OS through IL-6 secretion-mediated STAT3 activation. Additional administration of stattic in EGFR-targeted therapies may contribute to improve the efficacy for OS.

Anticancer Properties of Eugenol: A Review

Conventional cancer treatments have shown several unfavourable adverse effects, as well as an increase in anticancer drug resistance, which worsens the impending cancer therapy. Thus, the emphasis is currently en route for natural products. There is currently great interest in the natural bioactive components from medicinal plants possessing anticancer characteristics. For example, clove (Syzygium aromaticum L.) (Family Myrtaceae) is a highly prized spice that has been historically utilized as a food preservative and for diverse medical uses. It is reckoned amongst the valued sources of phenolics. It is indigenous to Indonesia but currently is cultivated in various places of the world. Among diverse active components, eugenol, the principal active component of S. aromaticum, has optimistic properties comprising antioxidant, anti-inflammatory, and anticancer actions. Eugenol (4-allyl-2-methoxyphenol) is a musky oil that is mainly obtained from clove. It has long been utilized all over the world as a result of its broad properties like antioxidant, anticancer, anti-inflammatory, and antimicrobial activities. Eugenol continues to pique investigators’ interest because of its multidirectional activities, which suggests it could be used in medications to treat different ailments. Anticancer effects of eugenol are accomplished by various mechanisms like inducing cell death, cell cycle arrest, inhibition of migration, metastasis, and angiogenesis on several cancer cell lines. Besides, eugenol might be utilized as an adjunct remedy for patients who are treated with conventional chemotherapy. This combination leads to a boosted effectiveness with decreased toxicity. The present review focuses on the anticancer properties of eugenol to treat several cancer types and their possible mechanisms.

Resolvin D1 attenuates acid-induced DNA damage in esophageal epithelial cells and rat models of acid reflux

The role of resolvin D1 (RvD1) in gastroesophageal reflux disease (GERD) remains largely unknown. Here, we investigated the potential role of RvD1 in acid-induced DNA damage in esophageal epithelial cells, patients with refractory GERD and a rat model of acid reflux. Weak acid exposure induced longer comet tails, reactive oxygen species (ROS) generation, oxidative DNA damage and DNA double-strand breaks (DSBs) in cells and RvD1 (0.1 μM) blocked all these effects. Mechanistic analyses showed that apart from ROS-reducing effects, RvD1 possessed a strong capacity to promote DNA damage repair, augmenting cell cycle checkpoint activity and DSB repair by modulating phosphatase and tensin homolog (PTEN) in cells. We also detected the surface expression of formyl peptide receptor 2 (FPR2), a receptor for RvD1, in the esophageal epithelial cells, and inhibition of FPR2 abrogated the protective effects of RvD1 on cells. Furthermore, a positive correlation between RvD1 and PTEN was observed predominantly in the esophageal epithelium from patients with refractory GERD (r = 0.67, P < 0.05). Additionally, RvD1 administration upregulated PTEN, suppressed DNA DSBs and alleviated microscopic damage in the rat model of gastric reflux. FPR2 gene silencing abolished the therapeutic effects of RvD1 on the rat model. Taken together, RvD1 binding to FPR2 protects the esophageal epithelium from acid reflux-induced DNA damage via a mechanism involving the inhibition of ROS production and facilitation of DSB repair. These findings support RvD1 as a promising approach that may be valuable for the treatment of GERD.

Engineered Bacteriorhodopsin May Induce Lung Cancer Cell Cycle Arrest and Suppress Their Proliferation and Migration

Highly expressible bacteriorhodopsin (HEBR) is a light-triggered protein (optogenetic protein) that has seven transmembrane regions with retinal bound as their chromophore to sense light. HEBR has controllable photochemical properties and regulates activity on proton pumping. In this study, we generated HEBR protein and incubated with lung cancer cell lines (A549 and H1299) to evaluate if there was a growth-inhibitory effect with or without light illumination. The data revealed that the HEBR protein suppressed cell proliferation and induced the G0/G1 cell cycle arrest without light illumination. Moreover, the migration abilities of A549 and H1299 cells were reduced by ~17% and ~31% after incubation with HEBR (40 μg/mL) for 4 h. The Snail-1 gene expression level of the A549 cells was significantly downregulated by ~50% after the treatment of HEBR. In addition, HEBR significantly inhibited the gene expression of Sox-2 and Oct-4 in H1299 cells. These results suggested that the HEBR protein may inhibit cell proliferation and cell cycle progression of lung cancer cells, reduce their migration activity, and suppress some stemness-related genes. These findings also suggested the potential of HEBR protein to regulate the growth and migration of tumor cells, which may offer the possibility for an anticancer drug.

Discovery of novel ibrutinib analogues to treat malignant melanoma

A series of novel ibrutinib analogues was synthesized, and their proliferation inhibitory activities against various B lymphoma cell lines (DaudiB and Raji) and solid tumor cells (B16, CT26, HepG2 and 4T1) were evaluated. The most potent compound, YL7, exhibited strong antiproliferative activity in all cell lines, and its IC50 value in B16 cells was almost 9-fold better than that of ibrutinib. Mechanism of action studies showed that YL7 inhibited proliferation and migration and induced G1 cell cycle arrest, apoptosis and autophagy in B16 cells. Further assessment of in vivo antitumor efficacies demonstrated that YL7 significantly inhibited the growth of B16 melanoma. These preliminary studies suggest that it is reasonable to modify the structure of ibrutinib for antimelanoma treatment.