Activation of endoplasmic reticulum stress by harmine suppresses the growth of esophageal squamous cell carcinoma.

The worldwide overall 5-year survival rate of esophageal squamous cell carcinoma (ESCC) patients is less than 20%, and novel therapeutic strategies for these patients are urgently needed. Harmine is a natural ß-carboline alkaloid, which received great interest in cancer research because of its biological and anti-tumor activities. The aim of this study is to examine the effects of harmine on ESCC and its mechanism. We investigated the effects of harmine on proliferation, cell cycle, apoptosis, and tumor growth in vivo. RNA sequencing (RNA-seq), real-time PCR, and western blotting were used to detect the mechanism. Harmine inhibited ESCC cell growth in vitro and tumor growth in vivo. Differentially expressed genes in harmine-treated ESCC cells were mainly involved in protein processing in the endoplasmic reticulum (ER). Real-time PCR and western blotting confirmed harmine-induced cellular ER stress. CRISPR-Cas9 knockout of C/EBP homologous protein (CHOP) abolished harmine-induced expression of death receptor 5 and apoptosis. Harmine also induced the expression of CHOP-mediated sestrin-2, which in turn contributes to autophagosome formation via suppressing the AMP-activated protein kinase-protein kinase B-mammalian target of rapamycin signaling pathway. In conclusion, our results demonstrate that harmine inhibits the growth of ESCC through its regulation of ER stress, suggesting that it is a promising candidate for ESCC treatment.

Dual inhibition of BET and HAT/p300 suppresses colorectal cancer via DR5- and p53/PUMA-mediated cell death.

Background: Colorectal cancer (CRC) frequently has a dysregulated epigenome causing aberrant up-regulation of oncogenes such as c-MYC. Bromodomain and extra-terminal domain (BET) proteins and histone acetyltransferases (HAT) are epigenetic regulatory proteins that create and maintain epigenetic states supporting oncogenesis. BET inhibitors and HAT inhibitors are currently being investigated as cancer therapeutics due to their ability to suppress cancer-promoting epigenetic modifiers. Due to the extensive molecular crosstalk between BET proteins and HAT proteins, we hypothesized that dual inhibition of BET and HAT could more potently inhibit CRC cells than inhibition of each individual protein. Methods: We investigated the activity and mechanisms of a dual BET and HAT inhibitor, NEO2734, in CRC cell lines and mouse xenografts. MTS, flow cytometry, and microscopy were used to assess cell viability. qPCR, Western blotting, and immunofluorescent staining were used to assess mechanisms of action. Results: We found that NEO2734 more potently suppresses CRC cell growth than first generation BET inhibitors, regardless of the status of common CRC driver mutations. We previously showed that BET inhibitors upregulate DR5 to induce extrinsic apoptosis. In the current study, we show that NEO2734 treatment induces CRC cell apoptosis via both the intrinsic and extrinsic apoptosis pathways. NEO2734 increases p53 expression and subsequently increased expression of the p53-upregulated mediator of apoptosis (PUMA), which is a critical mechanism for activating intrinsic apoptosis. We demonstrate that inhibition of either the intrinsic or extrinsic branches of apoptosis partially rescues CRC cells from NEO2734 treatment, while the dual inhibition of both branches of apoptosis more strongly rescues CRC cells from NEO2734 treatment. Finally, we show that NEO2734 monotherapy is able to suppress tumor growth in CRC xenografts by inducing apoptosis. Conclusions: Our study demonstrates NEO2734 potently suppresses CRC cells in vitro and in vivo by simultaneously upregulating PUMA and DR5 to induce cell death. Further studies of NEO2734 for treating CRC are warranted.

Reactive Oxygen Species Mediate 6c-Induced Mitochondrial and Lysosomal Dysfunction, Autophagic Cell Death, and DNA Damage in Hepatocellular Carcinoma.

Increasing the level of reactive oxygen species (ROS) in cancer cells has been suggested as a viable approach to cancer therapy. Our previous study has demonstrated that mitochondria-targeted flavone-naphthalimide-polyamine conjugate 6c elevates the level of ROS in cancer cells. However, the detailed role of ROS in 6c-treated cancer cells is not clearly stated. The biological effects and in-depth mechanisms of 6c in cancer cells need to be further investigated. In this study, we confirmed that mitochondria are the main source of 6c-induced ROS, as demonstrated by an increase in 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) and MitoSox fluorescence. Compound 6c-induced mitochondrial ROS caused mitochondrial dysfunction and lysosomal destabilization confirmed by absolute quantitation (iTRAQ)-based comparative proteomics. Compound 6c-induced metabolic pathway dysfunction and lysosomal destabilization was attenuated by N-acetyl-L-cysteine (NAC). iTRAQ-based comparative proteomics showed that ROS regulated the expression of 6c-mediated proteins, and treatment with 6c promoted the formation of autophagosomes depending on ROS. Compound 6c-induced DNA damage was characterized by comet assay, p53 phosphorylation, and γH2A.X, which was diminished by pretreatment with NAC. Compound 6c-induced cell death was partially reversed by 3-methyladenine (3-MA), bafilomycin (BAF) A1, and NAC, respectively. Taken together, the data obtained in our study highlighted the involvement of mitochondrial ROS in 6c-induced autophagic cell death, mitochondrial and lysosomal dysfunction, and DNA damage.

Design, Synthesis, and Biological Evaluation of Benzo[cd]indol-2(1H)-ones Derivatives as a Lysosome-Targeted Anti-metastatic Agent.

Lysosomes have become a hot topic in tumor therapy; targeting the lysosome is therefore a promising strategy in cancer therapy. Based on our previous lysosome-targeted bio-imaging agent, homospermine-benzo[cd]indol-2(1H)-one conjugate (HBC), we further developed three novel series of polyamine- benzo[cd]indol-2(1H)-one conjugates. Among them, compound 15f showed potent inhibitory activity in hepatocellular carcinoma migration both in vitro and in vivo. Our study results showed that compound 15f entered the cancer cells via the polyamine transporter localized in the lysosomes and caused autophagy and apoptosis. The mechanism of action revealed that the crosstalk between autophagy and apoptosis induced by 15f was mutually reinforcing patterns. Besides, 15f also targeted lysosomes and exhibited stronger green fluorescence than HBC, which indicated its potential as an imaging agent. To summarize, compound 15f could be used as a valuable dual-functional lead compound for future development against liver-cancer metastasis and lysosome imaging.

Suppression of oxidative phosphorylation and IDH2 sensitizes colorectal cancer to a naphthalimide derivative and mitoxantrone.

Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Oxidative phosphorylation (OXPHOS) has attracted a considerable attention in CRC. It is of great interest to explore novel therapies that inhibit OXPHOS for CRC treatment. Compound 6c is a novel naphthalimide derivative. However, the effects of 6c on CRC and the underlying mechanism are unclear. In this study, 6c suppressed CRC tumor growth and metastasis. RNA-seq data showed that 6c triggered the inhibition of OXPHOS and tricarboxylic acid cycle. 6c specifically inhibited mitochondrial complex III activity and the expression of isocitrate dehydrogenase 2 (IDH2), resulting in oxidative stress. Antioxidants reversed 6c-induced cell death, senescence, and autophagosomes formation. 6c inhibited autophagy flux; however, pretreatment with autophagy inhibitors resulted in the reduction of 6c-induced cytoplasmic vacuolization and proliferation inhibition. Moreover, combinatory treatment of 6c and mitoxantrone (MIT) showed stronger inhibitory effects on CRC compared with the single agent. Downregulation of IDH2 induced reactive oxygen species production, leading to MIT accumulation and autophagic cell death after co-treatment with 6c and MIT. In summary, our findings indicated 6c as a promising candidate for CRC treatment.

Identification of molecular anti-metastasis mechanisms of lycorine in colorectal cancer by RNA-seq analysis.

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies worldwide. Metastasis is the major cause of death in patients with CRC. Lycorine, the phenanthridine alkaloid most commonly found in spp of the Amaryllidaceae family, has shown promising anticancer activities with minor side effects. However, the effects and the detailed mechanism of lycorine against metastasis of CRC remains unclear. STUDY DESIGN/METHODS: The purpose of this study was to investigate the effects of lycorine on CRC and characterize the molecular mechanisms observed in lycorine-treated CRC cells using RNA-sequencing. MTT assay, colony formation assay, acridine orange/ethidium bromide (AO/EB) staining and Annexin V-FITC/Propidium iodide (PI) staining were conducted to examine the effects of lycorine on cell proliferation and apoptosis in CRC cells. RNA sequencing, real-time PCR assays and western blot were performed. Migration and invasion abilities of lycorine-treated CRC cells were investigated by wound healing and transwell invasion assays. The mouse CRC lung metastasis model was established and was used to detect the effect of lycorine on CRC in vivo. RESULTS: Our results demonstrated that lycorine inhibited the proliferation and colony formation of CRC cells in a concentration-dependent manner. AO/EB staining and Annexin V-FITC/PI staining showed that lycorine induced apoptosis in a concentration-dependent manner. Lycorine also reduced lung metastasis of CRC in vivo. Moreover, transcriptomic analysis suggested that lycorine regulated the expression of 3556 genes. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway was implicated according to the differentially expressed genes (DEGs), and multiple pathways including those of mitogen-activated protein kinase (MAPK), relaxin, Ras, phosphatidylinositol 3­kinase (PI3K)-protein kinase B (Akt) and Wnt/ß-catenin were selected by functional enrichment analyses. Furthermore, based on transcriptomic analysis, we found that the tumor necrosis factor (TNF) pathway and endoplasmic reticulum stress were responsible for lycorine-induced apoptosis. CONCLUSIONS: These results obtained in this study demonstrated that lycorine has the potential to suppress CRC in vitro and in vivo through the lycorine-regulated multiple signaling pathways.

The Role of p53-Mediated Signaling in the Therapeutic Response of Colorectal Cancer to 9F, a Spermine-Modified Naphthalene Diimide Derivative.

Colorectal cancer (CRC) is one of the most prevalent cancers due to its frequency and high rate of mortality. Polyamine-vectorized anticancer drugs possess multiple biological properties. Of these drugs, 9F has been shown to inhibit tumor growth and the metastasis of hepatocellular carcinoma. This current study aims to investigate the effects of 9F on CRC and determine its molecular mechanisms of action. Our findings demonstrate that 9F inhibits CRC cell growth by inducing apoptosis and cell cycle arrest, and suppresses migration, invasion and angiogenesis in vitro, resulting in the inhibition of tumor growth and metastasis in vivo. Based on RNA-seq data, further bioinformatic analyses suggest that 9F exerts its anticancer activities through p53 signaling, which is responsible for the altered expression of key regulators of the cell cycle, apoptosis, the epithelial-to-mesenchymal transition (EMT), and angiogenesis. In addition, 9F is more effective than amonafide against CRC. These results show that 9F can be considered as a potential strategy for CRC treatment.

Synthesis and biological evaluation of novel asymmetric naphthalene diimide derivatives as anticancer agents depending on ROS generation.

Naphthalenetetracarboxylic diimide (NDI) is widely used as a photoelectric material in the field of medicine. A series of asymmetric naphthalene diimide derivatives were synthesized and evaluated for their anticancer properties by various experimental assays. As the representative compound, 3c exerted significantly greater inhibitory effects on hepatoma cells SMMC-7721 and Hep G2 with an IC50 value of 1.48 ± 0.43 µM and 1.70 ± 0.53 µM, respectively, than normal hepatocytes QSG-7701 with an IC50 value of 7.11 ± 0.08 µM. Treatment with compound 3c (3 µM) for 48 h resulted in apoptosis of SMMC-7721 cells and Hep G2 cells with 52.1% and 67.8% apoptotic cells, respectively. Compound 3c induced autophagy and suppressed the migration of hepatoma cells in a concentration-dependent manner, resulting from the generation of reactive oxygen species (ROS). Based on its biological ability, compound 3c was considered as a potent anticancer agent.

Discovery of the Polyamine Conjugate with Benzo[ cd]indol-2(1 H)-one as a Lysosome-Targeted Antimetastatic Agent.

Polyamine derivatives have a promising prospect in dealing with disseminated tumor cells, a major obstacle in cancer therapy. To develop a bifunctional polyamine derivative that can serve as a fluorescent probe and an antimetastatic agent, three kinds of polyamine conjugates with benzo[ cd]indol-2(1 H)-one as a scaffold were designed and synthesized. Compound 5e was selected as a lead by in vitro screening. Two animal models demonstrated that 5e inhibited pulmonary metastasis and tumor growth. As a fluorescent probe, 5e might partially enter cells via a polyamine transporter and subsequently localize in the lysosome. Mechanistic investigations demonstrated the interdependence of 5e-triggered apoptosis and autophagy. Compound 5e modulated the expression of LC3-II, p62, cathepsins, and the expression of capases 3, caspase 8, Bcl-2, and p53. The SSAT-mediated Akt/ß-catenin pathways were also inhibited by 5e. The dual features of 5e make it a worthwhile lead compound for further structural optimization.

Synthesis and biological evaluation of naphthalimide-polyamine conjugates modified by alkylation as anticancer agents through p53 pathway.

In this study, a series of novel naphthalimide-polyamine conjugates modified by alkylation at the terminal of the polyamine chain were synthesized. These novel conjugates were evaluated for their anti-cancer activities. The results revealed that the length of the polyamine chain and the terminal alkyl group had influences on anticancer activities. Compound 3g was chosen to further study the anti-cancer mechanism and evaluate the anti-tumor efficacy in vivo. It induced intrinsic apoptosis and suppressed migration of hepatoma cells. The preliminary studies of compound 3gin vivo showed that it might be a promising candidate for cancer therapy.

Synthesis and biological evaluation of novel alkylated polyamine analogues as potential anticancer agents.

A new class of polyamine analogues modified by alkylation at the terminal of the polyamine chain has been synthesized and their structures were determined by 1H NMR, 13C NMR, ESI-MS and elemental analysis. As the representative compound, 3f displayed a broad spectrum of anti-cancer effects by MTT assays. Tumor xenograft model and pulmonary metastasis model showed that compound 3f significantly suppressed tumor growth and metastasis in vivo, which was more stronger than the reference drug amonafide. Molecular mechanisms indicated that compound 3f exhibited antiproliferative activities and induced the generation of reactive oxygen species (ROS), which resulted in the occurrence of autophagy. The downregulated expression of MMP-9 and ß-catenin by compound 3f accounted for the inhibition of migration. Taken altogether, the in vitro and in vivo biological evaluations corroborated compound 3f to be an effective anticancer agent.

Design, Synthesis and Evaluation of Naphthalimide Derivatives as Potential Anticancer Agents for Hepatocellular Carcinoma.

Two kinds of naphthalimide derivatives were synthesized and evaluated for in vitro their anti-hepatocellular carcinoma properties. Compound 3a with a fused thiazole fragment to naphthalimide skeleton inhibited cell migration of SMMC-7721 and HepG2, and further in vivo trials with two animal models confirmed that compound 3a moderately inhibited primary H22 tumor growth (52.6%) and potently interrupted lung metastasis (75.7%) without obvious systemic toxicity at the therapeutic dose. Mechanistic research revealed that compound 3a inhibited cancerous liver cell growth mostly by inducing G2/M phase arrest. Western blotting experiments corroborated that 3a could up-regulate the cell cycle related protein expression of cyclin B1, CDK1 and p21, and inhibit cell migration by elevating the E-cadherin and attenuating integrin α6 expression. Our study showed that compound 3a is a valuable lead compound worthy of further investigation.

Design, Synthesis, and Biological Evaluation of Mitochondria-Targeted Flavone-Naphthalimide-Polyamine Conjugates with Antimetastatic Activity.

Approximately 90% of cancer-associated deaths result from disseminated tumors, indicating the ineffectiveness of current therapies and the imperative need of antimetastatic drugs. A novel pharmacophore with flavonoid and naphthalimide moieties was constructed by using a fragment-based drug design and a series of eight flavone-naphthalimide-polyamine conjugates were synthesized. In vitro evaluation revealed that compound 6c with a homospermidine motif displayed better cell selectivity between cancerous and normal liver cells than amonafide did. The in vivo assays on two hepatocellular carcinoma (HCC) models verified that 6c potently suppressed pulmonary metastasis with improved organ indexes compared to amonafide. Various experiments showed that 6c as a potential fluorescent chemical probe could target the mitochondria. Preliminary investigation into the mechanism of action of 6c indicated that it might harness a polyamine transporter for cell entrance, localize in the mitochondria, selectively cause reactive oxygen species (ROS) overproduction in hepatoma cells instead of normal liver cells, and finally lead to HCC cell apoptosis and migration inhibition via multiple ROS-mediated signaling pathways.

Extracellular polyamines-induced proliferation and migration of cancer cells by ODC, SSAT, and Akt1-mediated pathway.

High levels of polyamines were observed and were related to a poor prognosis in cancer patients. However, the mechanism is not obvious. The aim of this study is to mimic the extracellular polyamines in a tumor microenviroment and to explore the role of extracellular polyamines in the proliferation and migration of cancer cells. Three different concentrations of polyamines composed of putrescine, spermidine, and spermine were used. Colony formation assay, wound healing assay, and transwell migration assay were performed. Akt1-overexpression cells were constructed. The related protein expression was examined using a western blot. In this study, polyamines promoted colony formation and cell migration in a concentration-dependent and time-dependent manner. Polyamines upregulated the expression of ornithine decarboxylase (ODC), SSAT, Akt1, Akt, hypoxia-inducible factors-1α, vascular endothelial growth factor, and matrix metalloproteinases, and downregulated p27 expression. The effects of combination of polyamines and Akt1 overexpression on colony formation and migration were more obvious than the effects of Akt1 overexpression alone. In Akt1-overexpression cells, polyamines also upregulated the expression of ODC, SSAT, hypoxia-inducible factors-1α, vascular endothelial growth factor, and matrix metalloproteinases and downregulated p27 expression. In conclusion, extracellular polyamines induced proliferation and cancer cell migration by inducing ODC and SSAT expression, and the Akt1-mediated pathway.

Spermidine/spermine N1-acetyltransferase regulates cell growth and metastasis via AKT/ß-catenin signaling pathways in hepatocellular and colorectal carcinoma cells.

Hepatocellular carcinoma (HCC) and colorectal cancer (CRC) are among the most common cancers across the world. Therefore, identifying the potential molecular mechanisms that promote HCC and CRC progression and metastasis are urgently needed. Spermidine/spermine N1-acetyltransferase (SSAT) is a catabolic enzyme that acetylates the high-order polyamines spermine and spermidine, thus decreasing the cellular content of polyamines. Several publications have suggested that depletion of intracellular polyamines inhibited tumor progression and metastasis in various cancer cells. However, whether and how SSAT regulates cell growth, migration and invasion in hepatocellular and colorectal carcinoma cells remains unclear. In this study, depletion of polyamines mediated by SSAT not only attenuated the tumor cell proliferation but also dramatically inhibited cell migration and invasion in hepatocellular and colorectal carcinoma cells. Subsequent investigations revealed introduction of SSAT into HepG2, SMMC7721 hepatocellular carcinoma cells and HCT116 colorectal carcinoma cells significantly suppressed p-AKT, p-GSK3ß expression as well as ß-catenin nuclear translocation, while inhibition of GSK3ß activity or exogenous polyamines could restore SSAT-induced decreases in the protein expression of p-AKT, p-GSK3ß and ß-catenin. Conversely, knockdown of SSAT in Bel7402 hepatocellular carcinoma cells and HT-29 colorectal carcinoma cells which expressed high levels of SSAT endogenously significantly promoted the expression of p-AKT, p-GSK3ß as well as ß-catenin nuclear translocation. Taken together, our results indicated depletion of polyamines by SSAT significantly inhibited cell proliferation, migration and invasion through AKT/GSK3ß/ß-catenin signaling pathway in hepatocellular carcinoma and colorectal cancer cells.

Farrerol inhibited angiogenesis through Akt/mTOR, Erk and Jak2/Stat3 signal pathway.

BACKGROUND: Farrerol is one of traditional Chinese medicines, isolated from Rhododendron dauricum L. It has been reported that Farrerol exerts multiple biological activities. Angiogenesis is an important drug target for cancer and inflammation therapy, the effect of Farrerol on angiogenesis is unknown. HYPOTHESIS/PURPOSE: We aimed to investigate whether Farrerol may have inhibitory effects against angiogenesis. STUDY DESIGN/METHODS: Two kinds of endothelial cells, named human umbilical vein endothelia cell and human micro vessel endothelial cells, were used to examine the effect and mechanism of Farrerol on angiogenesis. MTT assay was used to detect cell proliferation, wound healing assay and boyden's chamber assay were used to examine cell migration, Matrigel was used as basement membrane substratum in tube formation assay, Annexin V-FITC/PI dual staining assay and trypan blue staining were used to detect cell apoptosis, mouse aortic rings assay was performed as ex vivo assay, the expression of proteins involved in angiogenesis was tested using western blot, the binding of Farrerol to Stat3 was monitored by docking assay, molecular dynamics simulations and MM-GBSA method. RESULTS: Farrerol showed an inhibitory effect on proliferation, migration and tube formation of human umbilical vein endothelia cell and human micro vessel endothelial cells in a concentration-dependent manner. Farrerol induced cell cycle arrest and increased the apoptotic percentage of endothelial cells. Farrerol also suppressed the formation of new micro vessels from mouse aortic rings. Moreover, Farrerol reduced the phosphorylation levels of Erk, Akt, mTOR, Jak2 and Stat3 as well as protein expression of Bcl-2 and Bcl-xl. Docking assay, molecular dynamics simulations and MM-GBSA method showed that Farrerol bound to domain of Stat3, Ser613,Gln635, Glu638 and Thr714 are the main residues in Farrerol binding sites with the binding free energy -7.3 ∼ -9.0kcal/mol. CONCLUSIONS: In this study, we demonstrated that Farrerol inhibited angiogenesis through down regulation of Akt/mTOR, Erk and Jak2/Stat3 signal pathway. The inhibitory effect of Farrerol on angiogenesis suggested that this compound may be helpful to the angiogenesis-related diseases treatment, such as cancer and inflammations.

Inhibition of breast cancer progression by a novel histone deacetylase inhibitor, LW479, by down-regulating EGFR expression.

BACKGROUND AND PURPOSE: Compounds targeting epigenetic events of tumours are likely to be an important addition to anticancer therapy. Histone deacetylase inhibitors (HDACI) have emerged as a promising novel class for therapeutic interventions associated with cancer, and many of them are currently in clinical investigation. Here, we assessed a novel hydroxamate-based HDACI, LW479, in breast cancer progression and explored its underlying mechanism(s). EXPERIMENTAL APPROACH: LW479 was identified using the HDACI screening kit. Western blot and flow cytometry were used to analyse the biological effects of LW479 as a novel HDACI. The effects of LW479 were assessed in mouse models of spontaneous and experimental breast cancer. Co-immunoprecipitation, immunofluorescent staining and chromatin immunoprecipitation assays along with immunohistochemical analysis, were used to elucidate the molecular basis of the actions of LW479. KEY RESULTS: LW479 was identified as a novel HDACI and showed marked cytotoxicity and induced apoptosis, as well as cell cycle arrest, in a panel of breast cancer cell lines. Intraperitoneal injections of LW479 markedly suppressed breast tumour growth and pulmonary metastasis in nude mice. LW479 also decreased levels of EGF receptors (EGFR) by blocking the binding of the transcription factor Sp1 and HDAC1 to the EGFR promoter region. CONCLUSIONS AND IMPLICATIONS: Our data have elucidated the mechanisms underlying the inhibition by LW479 of tumour growth and metastasis, in models of breast cancer with aberrant EGFR expression. LW479 could be a candidate drug for breast cancer prevention.

A novel synthetic small molecule YH-306 suppresses colorectal tumour growth and metastasis via FAK pathway.

Cell migration and invasion are key processes in the metastasis of cancer, and suppression of these steps is a promising strategy for cancer therapeutics. The aim of this study was to explore small molecules for treating colorectal cancer (CRC) and to investigate their anti-metastatic mechanisms. In this study, six CRC cell lines were used. We showed that YH-306 significantly inhibited the migration and invasion of CRC cells in a dose-dependent manner. In addition, YH-306 inhibited cell adhesion and protrusion formation of HCT116 and HT-29 CRC cells. Moreover, YH-306 potently suppressed uninhibited proliferation in all six CRC cell lines tested and induced cell apoptosis in four cell lines. Furthermore, YH-306 inhibited CRC colonization in vitro and suppressed CRC growth in a xenograft mouse model, as well as hepatic/pulmonary metastasis in vivo. YH-306 suppressed the activation of focal adhesion kinase (FAK), c-Src, paxillin, and phosphatidylinositol 3-kinases (PI3K), Rac1 and the expression of matrix metalloproteases (MMP) 2 and MMP9. Meanwhile, YH-306 also inhibited actin-related protein (Arp2/3) complex-mediated actin polymerization. Taken together, YH-306 is a candidate drug in preventing growth and metastasis of CRC by modulating FAK signalling pathway.

Antitumor action of a novel histone deacetylase inhibitor, YF479, in breast cancer.

Accumulating evidence demonstrates important roles for histone deacetylase in tumorigenesis (HDACs), highlighting them as attractive targets for antitumor drug development. Histone deactylase inhibitors (HDACIs), which have shown favorable anti-tumor activity with low toxicity in clinical investigations, are a promising class of anticancer therapeutics. Here, we screened our compound library to explore small molecules that possess anti-HDAC activity and identified a novel HDACI, YF479. Suberoylanilide hydroxamic acid (SAHA), which was the first approved HDAC inhibitor for clinical treatment by the FDA, was as positive control in our experiments. We further demonstrated YF479 abated cell viability, suppressed colony formation and tumor cell motility in vitro. To investigate YF479 with superior pharmacodynamic properties, we developed spontaneous and experimental breast cancer animal models. Our results showed YF479 significantly inhibited breast tumor growth and metastasis in vivo. Further study indicated YF479 suppressed both early and end stages of metastatic progression. Subsequent adjuvant chemotherapy animal experiment revealed the elimination of local-regional recurrence (LRR) and distant metastasis by YF479. More important, YF479 remarkably prolonged the survival of tumor-bearing mice. Intriguingly, YF479 displayed more potent anti-tumor activity in vitro and in vivo compared with SAHA. Together, our results suggest that YF479, a novel HDACI, inhibits breast tumor growth, metastasis and recurrence. In light of these results, YF479 may be an effective therapeutic option in clinical trials for patients burdened by breast cancer.

Synthesis of novel heterocyclic ring-fused 18ß-glycyrrhetinic acid derivatives with antitumor and antimetastatic activity.

Glycyrrhetinic acid (GA) is one of the most important triterpenoic acids shows many pharmacological effects, especially antitumor activity. GA triggers apoptosis in various tumor cell lines. However, the antitumor activity of GA is weak, thus the synthesis of new synthetic analogs with enhanced potency is needed. By introducing various five-member fused heterocyclic rings at C-2 and C-3 positions, 18 novel GA derivatives were obtained. These compounds were evaluated for their inhibitory activity against the growth of eight different tumor cell lines using a SRB assay. The most active compound 37 showed IC50 between 5.19 and 11.72 µm, which was about 11-fold more potent than the lead compound GA. An apoptotic effect of GA and 37 was determined using flow cytometry and trypan blue exclusion assays. We also demonstrated here for the first time that GA and the synthetic derivatives exhibited inhibitory effect on migration of the tested tumor cells, especially 37 which was about 20-fold more potent than GA on antimetastatic activity.