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1.
Biomolecules ; 10(4)2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32244385

RESUMO

Triple-negative breast cancer (TNBC) is among the most aggressive and potentially metastatic malignancies. Most affected patients have poor clinical outcomes due to the lack of specific molecular targets on tumor cells. The upregulated expression of disruptor of telomeric silencing 1-like (DOT1L), a histone methyltransferase specific for the histone H3 lysine 79 residue (H3K79), is strongly correlated with TNBC cell aggressiveness. Therefore, DOT1L is considered a potential molecular target in TNBC. Fluoro-neplanocin A (F-NepA), an inhibitor of S-adenosylhomocysteine hydrolase, exhibited potent antiproliferative activity against various types of cancer cells, including breast cancers. However, the molecular mechanism underlying the anticancer activity of F-NepA in TNBC cells remains to be elucidated. We determined that F-NepA exhibited a higher growth-inhibitory activity against TNBC cells relative to non-TNBC breast cancer and normal breast epithelial cells. Moreover, F-NepA effectively downregulated the level of H3K79me2 in MDA-MB-231 TNBC cells by inhibiting DOT1L activity. F-NepA also significantly inhibited TNBC cell migration and invasion. These activities of F-NepA might be associated with the upregulation of E-cadherin and downregulation of N-cadherin and Vimentin in TNBC cells. Taken together, these data highlight F-NepA as a strong potential candidate for the targeted treatment of high-DOT1L-expressing TNBC.

2.
Anticancer Res ; 40(4): 1855-1866, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234873

RESUMO

BACKGROUND/AIM: The resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib or erlotinib, is considered a major challenge in the treatment of patients with non-small cell lung cancer (NSCLC). Herein, we identified the critical roles of anterior gradient 2 (AGR2) in gefitinib (Gef) resistance of mutant NSCLC cells. MATERIALS AND METHODS: Using datasets from a pair of NSCLC-sensitive and NSCLC-resistant cells, immunoblotting, immunofluorescence and immunohistochemistry, and cell viability assays were applied to identify the effects of AGR2. RESULTS: AGR2 was found to be significantly over-expressed in Gef-resistant cells and was highly associated with drug resistance, proliferation, migration, and invasion of cancer cells. Moreover, AGR2 and ADAMTS6 formed a negative feedback loop in drug-resistant cells. CONCLUSION: Modulation of overexpression of AGR2 in mutant NSCLC cells may be an attractive therapeutic strategy for the treatment of EGFR-TKI-resistant NSCLC.

3.
Mar Drugs ; 18(2)2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32013063

RESUMO

Skin is an important barrier to protect the body from environmental stress. However, exposure to ultraviolet radiation (UV) and various environmental oxidative stresses can cause skin inflammation. Cyclooxygenase-2 (COX-2) is an inducible enzyme that mediates the formation of prostaglandin E2 (PGE2) against internal and external inflammatory stimulations. Therefore, the inhibition of COX-2 is an important approach to maintain skin health and prevent skin inflammation and carcinogenesis. Topsentin, a bis(indolyl)imidazole alkaloid isolated from the marine sponge Spongosorites genitrix, has been reported to exhibit anti-tumor and anti-microbial activities. However, the effect of topsentin on skin inflammation and its underlying molecular mechanism has not been elucidated. In the present study, we identified the photoprotective effects of topsentin on UVB irradiated human epidermal keratinocyte HaCaT cells. Topsentin suppresses COX-2 expression and its upstream signaling pathways, AP-1 and MAPK. Furthermore, topsentin inhibits miR-4485, a new biomarker selected from a microarray, and its target gene tumor necrosis factor alpha induced protein 2 (TNF-α IP2). The photoprotective effect of topsentin was also confirmed in a reconstructed human skin model. These findings suggest that topsentin may serve as a potential candidate for cosmetic formulations with skin inflammatory-mediated disorder.

4.
Mar Drugs ; 18(2)2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32085561

RESUMO

Chemical profiling of the Streptomyces sp. strain SUD119, which was isolated from a marine sediment sample collected from a volcanic island in Korea, led to the discovery of three new metabolites: donghaecyclinones A-C (1-3). The structures of 1-3 were found to be rearranged, multicyclic, angucyclinone-class compounds according to nuclear magnetic resonance (NMR) and mass spectrometry (MS) analyses. The configurations of their stereogenic centers were successfully assigned using a combination of quantum mechanics-based computational methods for calculating the NMR shielding tensor (DP4 and CP3) as well as electronic circular dichroism (ECD) along with a modified version of Mosher's method. Donghaecyclinones A-C (1-3) displayed cytotoxicity against diverse human cancer cell lines (IC50: 6.7-9.6 µM for 3).

5.
Mar Drugs ; 18(2)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069904

RESUMO

Marine-derived microorganisms are a valuable source of novel bioactive natural products. Asperphenin A is a lipopeptidyl benzophenone metabolite isolated from large-scale cultivation of marine-derived Aspergillus sp. fungus. The compound has shown potent antiproliferative activity against various cancer cells. However, the underlying mechanism of action remained to be elucidated. In this study, we demonstrated the antitumor activity and molecular mechanism of asperphenin A in human colon cancer cells for the first time. Asperphenin A inhibited the growth of colon cancer cells through G2/M cell cycle arrest followed by apoptosis. We further discovered that asperphenin A can trigger microtubule disassembly. In addition to its effect on cell cycle, asperphenin A-induced reactive oxygen species. The compound suppressed the growth of tumors in a colon cancer xenograft model without any overt toxicity and exhibited a combination effect with irinotecan, a topoisomerase I inhibitor. Moreover, we identified the aryl ketone as a key component in the molecular structure responsible for the biological activity of asperphenin A using its synthetic derivatives. Collectively, this study has revealed the antiproliferative and antitumor mechanism of asperphenin A and suggested its possibility as a chemotherapeutic agent and lead compound with a novel structure.

6.
Sci Adv ; 6(6): eaav7416, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32083171

RESUMO

Secondary drug resistance stems from dynamic clonal evolution during the development of a prior primary resistance. This collateral type of resistance is often a characteristic of cancer recurrence. Yet, mechanisms that drive this collateral resistance and their drug-specific trajectories are still poorly understood. Using resistance selection and small-scale pharmacological screens, we find that cancer cells with primary acquired resistance to the microtubule-stabilizing drug paclitaxel often develop tolerance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), leading to formation of more stable resistant cell populations. We show that paclitaxel-resistant cancer cells follow distinct selection paths under EGFR-TKIs by enriching the stemness program, developing a highly glycolytic adaptive stress response, and rewiring an apoptosis control pathway. Collectively, our work demonstrates the alterations in cellular state stemming from paclitaxel failure that result in collateral resistance to EGFR-TKIs and points to new exploitable vulnerabilities during resistance evolution in the second-line treatment setting.

7.
J Nat Prod ; 83(2): 277-285, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32073848

RESUMO

The cultivation of a Streptomyces sp. SD53 strain isolated from the gut of the silkworm Bombyx mori produced two macrolactam natural products, piceamycin (1) and bombyxamycin C (2). The planar structures of 1 and 2 were identified by a combination of NMR, MS, and UV spectroscopic analyses. The absolute configurations were assigned based on chemical and chromatographic methods as well as ECD calculations. A new chromatography-based experimental method for determining the configurations of stereogenic centers ß to nitrogen atoms in macrolactams was established and successfully applied in this report. These compounds exhibited significant bioactivities against the silkworm entomopathogen Bacillus thuringiensis and various human pathogens as well as human cancer cell lines. In particular, piceamycin potently inhibited Salmonella enterica and Proteus hauseri with MIC values of 0.083 µg/mL and 0.025 µg/mL, respectively. The biosynthetic pathway involved in the formation of the cyclopentenone moiety in piceamycin is discussed.

8.
Molecules ; 25(3)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041324

RESUMO

Aberrant activation of a Wnt/ß-catenin pathway results in nuclear accumulation of ß-catenin in colon cancer. Inhibiting ß-catenin is one strategy for treating colon cancer. Here, we identified Z-ajoene, a sulfur containing compound isolated from crushed garlic, as an inhibitor of colon cancer cell growth. Z-Ajoene repressed ß-catenin response transcriptional activity, intracellular ß-catenin levels, and its representative target protein levels (c-Myc and cyclin D1) in SW480 colon cancer cells. To clarify the regulatory mechanism of decreased ß-catenin levels, we examined the effect of Z-ajoene on ß-catenin phosphorylation, which is involved in ß-catenin degradation. Z-Ajoene promoted the phosphorylation of ß-catenin at Ser45 in a casein kinase 1α (CK1α)-dependent manner, which is an essential step in ß-catenin degradation in the cytosol. These findings indicate that Z-ajoene from garlic may be a potential chemotherapeutic agent by modulating CK1α activity and the Wnt/ß-catenin signaling pathway.

9.
Fitoterapia ; 142: 104486, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31987982

RESUMO

Inflammation is a very common and important basic pathological process. There is still a great need for the isolation of effective anti-inflammatory agents from plants. In this paper, five new isobutylamides, zanthoxylumamides E-I (1-5), and four known isobutylamides (6-9) were isolated from Zanthoxylum nitidum var. tomentosum (Rutaceae). Chiral resolution of seven racemic isobutylamides (1-4 and 6-8) was successfully performed, and the absolute configurations of two stereoisomers of 1-4 were validated by ECD and NMR. The obtained isobutylamides were evaluated in vitro anti-inflammatory activity with the lipopolysaccharide (LPS)-stimulated production of nitric oxide (NO) in murine macrophage RAW264.7 cells. Compound 8 exhibited significant inhibition of LPS-induced NO production. The underlying molecular mechanisms of the anti-inflammatory activity of 8 revealed that it suppressed the NO production through the modulation of myeloid differentiation factor 88 (MyD88) and interferon regulatory factor 3 (IRF3) signaling pathways.

10.
J Nat Prod ; 83(1): 118-126, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31894983

RESUMO

Ohmyungsamycin A (1), a novel cyclic peptide discovered from a marine Streptomyces sp., was previously reported with antibacterial and anticancer activities. However, the antitumor activities and the underlying molecular mechanisms of 1 remain to be elucidated. Compound 1 inhibited the proliferation and tumor growth of HCT116 human colorectal cancer cells based on both in vitro cell cultures and an in vivo animal model. A cDNA microarray analysis revealed that 1 downregulated genes involved in cell cycle checkpoint control. Compound 1 also induced G0/G1 cell cycle arrest that was mediated by the regulation of S-phase kinase-associated protein 2 (Skp2)-p27 axis and minichromosome maintenance protein 4 (MCM4). Furthermore, a longer exposure of 1 exhibited an accumulation of a sub-G1 phase cell population, which is characteristic of apoptotic cells. The induction of apoptosis by 1 was also associated with the modulation of caspase family proteins. Compound 1 effectively suppressed tumor growth in a xenograft mouse model subcutaneously implanted with HCT116 cells. In addition, analysis of tumors revealed that 1 upregulated the expression of the CDK inhibitor p27 but downregulated the expression of Skp2 and MCM4. These findings demonstrate the involvement of 1 in cell cycle regulation and the induction of apoptosis in human colorectal cancer cells.

11.
Molecules ; 25(3)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979361

RESUMO

Oxypeucedanin (OPD), a furocoumarin compound from Angelica dahurica (Umbelliferae), exhibits potential antiproliferative activities in human cancer cells. However, the underlying molecular mechanisms of OPD as an anticancer agent in human hepatocellular cancer cells have not been fully elucidated. Therefore, the present study investigated the antiproliferative effect of OPD in SK-Hep-1 human hepatoma cells. OPD effectively inhibited the growth of SK-Hep-1 cells. Flow cytometric analysis revealed that OPD was able to induce G2/M phase cell cycle arrest in cells. The G2/M phase cell cycle arrest by OPD was associated with the downregulation of the checkpoint proteins cyclin B1, cyclin E, cdc2, and cdc25c, and the up-regulation of p-chk1 (Ser345) expression. The growth-inhibitory activity of OPD against hepatoma cells was found to be p53-dependent. The p53-expressing cells (SK-Hep-1 and HepG2) were sensitive, but p53-null cells (Hep3B) were insensitive to the antiproliferative activity of OPD. OPD also activated the expression of p53, and thus leading to the induction of MDM2 and p21, which indicates that the antiproliferative activity of OPD is in part correlated with the modulation of p53 in cancer cells. In addition, the combination of OPD with gemcitabine showed synergistic growth-inhibitory activity in SK-Hep-1 cells. These findings suggest that the anti-proliferative activity of OPD may be highly associated with the induction of G2/M phase cell cycle arrest and upregulation of the p53/MDM2/p21 axis in SK-HEP-1 hepatoma cells.

12.
Biomol Ther (Seoul) ; 28(2): 145-151, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31697876

RESUMO

Alzheimer's disease (AD) is a devastating neurodegenerative disease and a major cause of dementia in elderly individuals worldwide. Increased deposition of insoluble amyloid ß (Aß) fibrils in the brain is thought be a key neuropathological hallmark of AD. Many recent studies show that natural products such as polyphenolic flavonoids inhibit the formation of insoluble Aß fibrils and/or destabilize ß-sheet-rich Aß fibrils to form non-cytotoxic aggregates. In the present study, we explored the structure-activity relationship of naturally-occurring biflavonoids on Aß amyloidogenesis utilizing an in vitro thioflavin T assay with Aß1-42 peptide which is prone to aggregate more rapidly to fibrils than Aß1-40 peptide. Among the biflavonoids we tested, we found amentoflavone revealed the most potent effects on inhibiting Aß1-42 fibrillization (IC50: 0.26 µM), as well as on disassembling preformed Aß1-42 fibrils (EC50: 0.59 µM). Our structure-activity relationship study suggests that the hydroxyl groups of biflavonoid compounds play an essential role in their molecular interaction with the dynamic process of Aß1-42 fibrillization. Our atomic force microscopic imaging analysis demonstrates that amentoflavone directly disrupts the fibrillar structure of preformed Aß1-42 fibrils, resulting in conversion of those fibrils to amorphous Aß1-42 aggregates. These results indicate that amentoflavone affords the most potent anti-amyloidogenic effects on both inhibition of Aß1-42 fibrillization and disaggregation of preformed mature Aß1-42 fibrils.

13.
J Photochem Photobiol B ; 202: 111704, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31743829

RESUMO

Ultraviolet B (UVB) induces inflammation and causes skin aging. The signs of skin aging, such as wrinkles, discolored spots, loss of skin moisture, and disruption of the skin barrier, are mostly caused by inflammatory signaling among various skin layers. The cells on the outermost surface of the skin are keratinocytes; these cells protect the skin against environmental stress and play an important role in immunomodulation by secreting cytokines in response to environmental stress. In the present study, we found that UVB activates STAT1 to mediate inflammatory signaling, yet STAT1 (S272) and STAT (Y702) shows different responses against UVB exposure. Anhua drak tea is a post-fermented dark tea produced in Anhua and Xinhua country in Hunan province of China. Treatment with 2S,3R-6-methoxycarbonylgallocatechin (MCGE), an epigallocatechin gallate derivative isolated from black tea (Anhua dark tea), effectively suppresses STAT1 activation and inflammatory cytokines, and activates Nrf2 pathway to protect cells from reactive oxygen species production in UVB exposed keratinocyte cells (HaCaT). Interestingly, the effects of MCGE were independent on MAPK signaling pathway. Moreover, MCGE regulates inflammatory cytokines in monocyte-keratinocyte (THP-1, HaCaT) co-culture and macrophage differentiation models. These results suggest that MCGE potentially can be used as a photoprotective agent against UVB-induced inflammatory responses.


Assuntos
Catequina/farmacologia , Protetores contra Radiação/farmacologia , Transdução de Sinais/efeitos dos fármacos , Chá/química , Raios Ultravioleta , Sítios de Ligação , Catequina/análogos & derivados , Catequina/química , Catequina/isolamento & purificação , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Técnicas de Cocultura , Citocinas/metabolismo , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/efeitos da radiação , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estrutura Terciária de Proteína , Protetores contra Radiação/química , Protetores contra Radiação/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT1/química , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos da radiação , Chá/metabolismo
14.
J Nat Prod ; 82(11): 3056-3064, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31668072

RESUMO

Three new germacrane sesquiterpenoid-type alkaloids with an unusual Δ8-7,12-lactam moiety, glechomanamides A-C (1-3), and two pairs of 7,12-hemiketal sesquiterpenoid epimers (4a/b, 5a/b) were isolated from Salvia scapiformis. Their structures were elucidated by spectroscopic methods including HRESIMS, IR, UV, and 1D and 2D NMR and also confirmed by single-crystal X-ray diffraction analysis. The chemical transformation of compounds 1-5 in a solution environment was analyzed by 2D NMR spectroscopy. The aza acetallactams (1-3) were stable in organic solvent, while single crystals of the hemiacetal esters (4a/b, 5a/b) underwent a tautomeric equilibrium after being dissolved. Single crystals of 4a, 4b, and 5a were obtained for the first time as their naturally occurring forms. Glechomanamide B (2) exhibited antiangiogenic activity by suppression of vascular endothelial growth factor (VEGF)-induced tube formation through modulation of VEGF receptor 2 (VEGFR2)-mediated signaling pathways in human umbilical vascular endothelial cells (HUVECs). In addition, compound 2 also showed the significant suppression of mRNA expression associated with glycolysis and angiogenesis biomarkers in high glucose (30 mM)-induced HUVECs. These findings suggest that compound 2 might be a potential lead compound candidate for the management of diabetic retinopathy.

15.
Biomolecules ; 9(11)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671649

RESUMO

The cyclic depsipeptides ohmyungsamycin (OMS) A (1) and B (2), isolated from the marine-derived Streptomyces sp. SNJ042, contain two non-proteinogenic amino acid residues, ß-hydroxy-l-phenylalanine (ß-hydroxy-l-Phe) and 4-methoxy-l-tryptophan (4-methoxy-l-Trp). Draft genome sequencing of Streptomyces sp. SNJ042 revealed the OMS biosynthetic gene cluster consisting of a nonribosomal peptide synthetase (NRPS) gene and three genes for amino acid modification. By gene inactivation and analysis of the accumulated products, we found that OhmL, encoding a P450 gene, is an l-Phe ß-hydroxylase. Furthermore, OhmK, encoding a Trp 2,3-dioxygenase homolog, and OhmJ, encoding an O-methyltransferase, are suggested to be involved in hydroxylation and O-methylation reactions, respectively, in the biosynthesis of 4-methoxy-l-Trp. In addition, the antiproliferative and antituberculosis activities of the OMS derivatives dehydroxy-OMS A (4) and demethoxy-OMS A (6) obtained from the mutant strains were evaluated in vitro. Interestingly, dehydroxy-OMS A (4) displayed significantly improved antituberculosis activity and decreased cytotoxicity compared to wild-type OMS A.

16.
Mol Ther Oncolytics ; 15: 140-152, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31720371

RESUMO

Triple-negative breast cancer (TNBC) is the most intractable cancer in women with a high risk of metastasis. While hyper-methylation of histone H3 catalyzed by disruptor of telomeric silencing 1-like (DOT1L), a specific methyltransferase for histone H3 at lysine residue 79 (H3K79), is reported as a potential target for TNBCs, early developed nucleoside-type DOT1L inhibitors are not sufficient for effective inhibition of growth and metastasis of TNBC cells. We found that TNBC cells had a high expression level of DOT1L and a low expression level of E-cadherin compared to normal breast epithelial cells and non-TNBC cells. Here, a novel psammaplin A analog (PsA-3091) exhibited a potent inhibitory effect of DOT1L-mediated H3K79 methylation. Consistently, PsA-3091 also significantly inhibited the proliferation, migration, and invasion of TNBC cells along with the augmented expression of E-cadherin and the suppression of N-cadherin, ZEB1, and vimentin expression. In an orthotopic mouse model, PsA-3091 effectively inhibited lung metastasis and tumor growth by the regulation of DOT1L activity and EMT biomarkers. Together, we report here a new template of DOT1L inhibitor and suggest that targeting DOT1L-mediated H3K79 methylation by a novel PsA analog may be a promising strategy for the treatment of metastatic breast cancer patients.

17.
J Nat Prod ; 82(11): 3140-3149, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31622095

RESUMO

A flavonoid glycoside, quercitrin (1), and two phenylpropanoyl sucrose derivatives, vanicoside B (2) and lapathoside C (3), were isolated for the first time from the herb Persicaria dissitiflora. Vanicoside B (2) exhibited antiproliferative activity against a panel of cancer cell lines in triple-negative breast cancer (TNBC) MDA-MB-231 cells. The underlying mechanisms of the antitumor activity of 2 were investigated in TNBC cells. Upregulation of cyclin-dependent kinase 8 (CDK8) was observed in a claudin-low molecular subtype of TNBC cells. A molecular modeling study indicated that 2 showed a high affinity for CDK8. Further investigations revealed that 2 suppressed CDK8-mediated signaling pathways and the expression of epithelial-mesenchymal transition proteins and induced cell cycle arrest and apoptosis in MDA-MB-231 and HCC38 TNBC cells. Moreover, 2 inhibited tumor growth without overt toxicity in a nude mouse xenograft model implanted with MDA-MB-231 cells. Taken together, these findings demonstrate the significance of CDK8 activity in TNBC and suggest a potential use of 2 as a therapeutic candidate for the treatment of aggressive human triple-negative breast cancer.

18.
Mediators Inflamm ; 2019: 7651470, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31182933

RESUMO

Lumbar spinal stenosis (LSS) is a major cause of chronic low back pain; however, only a few therapies which have been used in clinics still have limited effects on functional recovery. SHINBARO2 is a refined traditional formulation for inflamed lesions and relieve pain of muscular skeletal disease. This study aimed at investigating the effects of SHINBARO2 on LSS and at determining its underlying molecular mechanism in rat models. The LSS rat models were set up by surgical operations in 6-week-old male Sprague-Dawley rats. SHINBARO2 was orally or intraperitoneally administered for 14 days. The motor and sensory ability of rats were evaluated using the activity cage and hot plate method. On the termination day, total vertebrae including the disc and spinal cord were excised for ex vivo study. SHINBARO2 improved locomotor functions and pain sensitivity in LSS rat models. Mechanism study suggested that SHINBARO2 inhibited the production of nitric oxide and prostaglandin E2 in tissues from LSS-induced rats. SHINBARO2 also suppressed the expression of proinflammatory cytokines including tumor necrosis factor-α and interleukin-1ß. The activation of NF-κB by LSS surgery was effectively reduced by SHINBARO2, which coincided with the inhibition of IκB degradation. In addition, brain-derived neurotrophic factor (BDNF), a potent promoter of neurite growth, and its downstream ERK signaling were also regulated by SHINBARO2. These findings suggest that the effect of SHINBARO2 might be associated in part with the anti-inflammation and pain control in LSS rat models.


Assuntos
Anti-Inflamatórios/uso terapêutico , Estenose Espinal/tratamento farmacológico , Animais , Anti-Inflamatórios/química , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Imuno-Histoquímica , Interleucina-1beta/metabolismo , Locomoção/fisiologia , Masculino , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Estenose Espinal/imunologia , Estenose Espinal/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
19.
Cell Death Dis ; 10(5): 361, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043587

RESUMO

Acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) has been a major obstacle in the treatment of non-small cell lung cancer (NSCLC) patients. AXL has been reported to mediate EGFR-TKIs. Recently, third generation EGFR-TKI osimertinib has been approved and yet its acquired resistance mechanism is not clearly understood. We found that AXL is involved in both gefitinib and osimertinib resistance using in vitro and in vivo model. In addition, AXL overexpression was correlated with extended protein degradation rate. We demonstrate targeting AXL degradation is an alternative route to restore EGFR-TKIs sensitivity. We confirmed that the combination effect of YD, an AXL degrader, and EGFR-TKIs can delay or overcome EGFR-TKIs-driven resistance in EGFR-mutant NSCLC cells, xenograft tumors, and patient-derived xenograft (PDX) models. Therefore, combination of EGFR-TKI and AXL degrader is a potentially effective treatment strategy for overcoming and delaying acquired resistance in NSCLC.

20.
Cancers (Basel) ; 11(5)2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060329

RESUMO

Aberrant activation of hepatocyte growth factor (HGF)/c-Met signaling pathway caused by gene amplification or mutation plays an important role in tumorigenesis. Therefore, c-Met is considered as an attractive target for cancer therapy and c-Met inhibitors have been developed with great interests. However, cancers treated with c-Met inhibitors inevitably develop resistance commonly caused by the activation of PI3K/Akt signal transduction pathway. Therefore, the combination of c-Met and PI3Kα inhibitors showed synergistic activities, especially, in c-Met hyperactivated and PIK3CA-mutated cells. In our previous study, we rationally designed and synthesized DFX117(6-(5-(2,4-difluorophenylsulfonamido)-6-methoxypyridin-3-yl)-N-(2-morpholinoethyl) imidazo[1,2-a]pyridine-3-carboxamide) as a novel PI3Kα selective inhibitor. Herein, the antitumor activity and underlying mechanisms of DFX117 against non-small cell lung cancer (NSCLC) cells were evaluated in both in vitro and in vivo animal models. Concurrent targeted c-Met and PI3Kα by DFX117 dose-dependent inhibited the cell growth of H1975 cells (PIK3CA mutation and c-Met amplification) and A549 cells (KRAS mutation). DFX117 subsequently induced G0/G1 cell cycle arrest and apoptosis. These data highlight the significant potential of DFX117 as a feasible and efficacious agent for the treatment of NSCLC patients.

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