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c-MET and STAT-3 are significant targets for cancer treatments. Here, we describe a class of very effective dual STAT-3 and c-MET inhibitors with coumarin-based thiazoles (3a-o) as its scaffold. Spectroscopic evidence (NMR, HRMS, and HPLC) validated the structural discoveries of the new compounds. The cytotoxic activity of these compounds was also tested against a panel of cancer cells in accordance with US-NCI guidelines. Compound 3g proved to be active at 10 µM, thus it was automatically scheduled to be tested at five doses. Towards SNB-75 (CNS cancer cell line), compound 3g showed notable in vitro anti-cancer activity with GI50 = 1.43 µM. For the molecular targets, compound 3g displayed potent activity towards STAT-3 and c-MET having IC50 of 4.7 µM and 12.67, respectively, compared to Cabozantinib (IC50 = 15 nM of c-MET) and STAT-3-IN-3 (IC50 = 2.1 µM of STAT-3). Moreover, compound 3g significantly induced apoptosis in SNB-75 cells, causing a 3.04-fold increase in apoptotic cell death (treated cells exhibited 11.53 % overall apoptosis, against 3.04 % in reference cells) and a 3.58-fold increase in necrosis. Moreover, it arrests cells at the G2 phase. Dual inhibition of c-MET and STAT-3 protein kinase was further validated using RT-PCR. The target compound's binding mechanism was determined by the application of molecular docking.
Assuntos
Antineoplásicos , Proliferação de Células , Cumarínicos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas Proto-Oncogênicas c-met , Fator de Transcrição STAT3 , Tiazóis , Humanos , Cumarínicos/farmacologia , Cumarínicos/química , Cumarínicos/síntese química , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Tiazóis/farmacologia , Tiazóis/química , Tiazóis/síntese química , Relação Estrutura-Atividade , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Simulação de Acoplamento MolecularRESUMO
The use of VEGFR-2 inhibitors as a stand-alone treatment has proven to be ineffective in clinical trials due to the robustness of cellular response loops that lead to treatment resistance when only targeting VEGFR-2. The over-activation of the signal transducer/activator of transcription 3 (STAT-3) is expected to significantly impact treatment failure and resistance to VEGFR-2 inhibitors. In this study, we propose the concept of combined inhibition of VEGFR-2 and STAT-3 to combat induced STAT-3-mediated resistance to VEGFR-2 inhibition therapy. To explore this, we synthesized new isatin-grafted phenyl-1,2,3-triazole derivatives "6a-n" and "9a-f". Screening on PANC1 and PC3 cancer cell lines revealed that compounds 6b, 6 k, 9c, and 9f exhibited sub-micromolar ranges. The most promising molecules, 6b, 6 k, 9c, and 9f, demonstrated the highest inhibition when tested as dual inhibitors on VEGFR-2 (with IC50 range 53-82 nM, respectively) and STAT-3 (with IC50 range 5.63-10.25 nM). In particular, triazole 9f showed the best results towards both targets. Inspired by these findings, we investigated whether 9f has the ability to trigger apoptosis in prostate cancer PC3 cells via the assessment of the expression levels of the apoptotic markers Caspase-8, Bcl-2, Bax, and Caspase-9. Treatment of the PC3 cells with compound 9f significantly inhibited the protein expression levels of VEGFR-2 and STAT-3 kinases compared to the control.
Assuntos
Antineoplásicos , Proliferação de Células , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Isatina , Inibidores de Proteínas Quinases , Fator de Transcrição STAT3 , Triazóis , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Humanos , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Isatina/farmacologia , Isatina/química , Isatina/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Relação Estrutura-Atividade , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular TumoralRESUMO
BACKGROUND: Colon cancer has high mortality rate which making it one of the leading causes of cancer deaths. Oxaliplatin is a common chemotherapeutic drug, but it has disadvantages such as drug resistance. OBJECTIVE: The purpose of this study is to explore the mechanism of exosomes in the resistance of oxaliplatin and verify whether elemene and STAT3 inhibitors reverse the resistance to oxaliplatin. METHODS: Related cell line models were constructed and the proliferation, migration, invasion, apoptosis and resistance to oxaliplatin were evaluated for all three cells of HCT116/L, sensitive cell HCT116 and HCT116+HCT116/L-exosomes (HCT116-exo). It was to explore probable signaling pathways and mechanisms by Western blotting. RESULTS: HCT116-exo drug-resistant chimeric cells showed greater capacity for proliferation, migration and invasion than HCT116 sensitive cells. After the above cells were treated with oxaliplatin, the apoptosis rate of chimeric drug-resistant cells HCT116-exo and its IC50 increased compared with the sensitive cells HCT116. The proliferation, invasion and migration of cells treated with STAT3 inhibitor or ß-elemene combined with oxaliplatin reduced compared with those treated with oxaliplatin or ß-elemene alone. The STAT3 inhibitor or ß-elemene in combination with oxaliplatin increased the rate of apoptosis relative to oxaliplatin or ß-elemene alone. Drug-resistant cell exosomes could promote the EMT process, related to the participation of FGFR4, SHMT2 and STAT3 inhibitors. CONCLUSION: Drug-resistant cell exosomes could induce resistance, and improve the capacity of colon cancer towards proliferate, invade, migrate and promote the EMT process. The ß-elemene combined with oxaliplatin could reverse the above results which might be related to the STAT3 pathway and EMT pathway in colon cancer.
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Medulloblastoma is a type of brain cancer that primarily affects children. While chemotherapy has been shown to be effective in treating medulloblastoma, the development of chemotherapy resistance remains a challenge. One potential therapeutic approach is to selectively inhibit the inducible transcription factor called STAT3, which is known to play a crucial role in the survival and growth of tumor cells. The activation of STAT3 has been linked to the growth and progression of various cancers, including medulloblastoma. Inhibition of STAT3 has been shown to sensitize medulloblastoma cells to chemotherapy, leading to improved treatment outcomes. Different approaches to STAT3 inhibition have been developed, including small-molecule inhibitors and RNA interference. Preclinical studies have shown the efficacy of STAT3 inhibitors in medulloblastoma, and clinical trials are currently ongoing to evaluate their safety and effectiveness in patients with various solid tumors, including medulloblastoma. In addition, researchers are also exploring ways to optimize the use of STAT3 inhibitors in combination with chemotherapy and identify biomarkers that can predict treatment that will help to develop personalized treatment strategies. This review highlights the potential of selective inhibition of STAT3 as a novel approach for the treatment of medulloblastoma and suggests that further research into the development of STAT3 inhibitors could lead to improved outcomes for patients with aggressive cancer.
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The signal transducer and activator of transcription 3 (STAT3) has been established as a crucial drug target in the development of antitumor agents. In this study, a series of 21 derivatives of the STAT3 inhibitor napabucasin were designed and synthesized. Through preliminary screening against tumor cell lines, SZ6 emerged as the most potent compound with half maximal inhibitory concentration (IC50) values of 46.3 nM, 66.4 nM, and 53.8 nM against HCT116, HepG2, and Hela cells respectively. Furthermore, SZ6 effectively suppressed tumor invasion and migration in HCT116 cell assays by inducing S-phase arrest and apoptosis through inhibition of Protein Kinase B (PKB/AKT) activity and induction of reactive oxygen species (ROS). The mechanism underlying SZ6's action involves inhibition of STAT3 phosphorylation, which was confirmed by western blotting analysis. Additionally, surface plasmon resonance (SPR) and cellular thermal shift assay (CETSA) demonstrated direct binding between SZ6 and STAT3. Notably, in vivo studies revealed that SZ6 significantly inhibited tumor growth without any observed organ toxicity. Collectively, these findings identify SZ6 as a promising STAT3 inhibitor for colorectal cancer treatment.
Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fator de Transcrição STAT3 , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Animais , Tiazóis/farmacologia , Tiazóis/química , Tiazóis/síntese química , Camundongos , Naftoquinonas/farmacologia , Naftoquinonas/síntese química , Naftoquinonas/química , Camundongos Nus , Camundongos Endogâmicos BALB C , Movimento Celular/efeitos dos fármacos , BenzofuranosRESUMO
A category of cytoplasmic transcription factors called STATs mediates intracellular signaling, which is frequently generated at receptors on cell surfaces and subsequently sent to the nucleus. STAT3 is a member of a responsible for a variety of human tumor forms, including lymphomas, hematological malignancies, leukemias, multiple myeloma and several solid tumor types. Numerous investigations have demonstrated constitutive STAT3 activation lead to cancer development such as breast, head and neck, lung, colorectal, ovarian, gastric, hepatocellular, and prostate cancers. It's possible to get a hold of the book here. Tumor cells undergo apoptosis when STAT3 activation is suppressed. This review highlights the STAT3 activation and inhibition which can be used for further studies.
Assuntos
Antineoplásicos , Neoplasias , Fator de Transcrição STAT3 , Humanos , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
In part due to the resilience of cellular feedback pathways that develop therapeutic resistance to targeting the EGFR alone, using EGFR inhibitors alone was demonstrated to be unsuccessful in clinical trials. The over-activation of the signal transducer/activator of transcription 3 (STAT3) during the administration of an EGFR inhibitor is expected to play a substantial part in the failure and resistance of EGFR inhibitor treatment. Therein, we proposed a hypothesis that induced STAT3-mediated resistance to EGFR inhibition therapy could be addressed by a dual inhibition of EGFR and STAT3 method. To this end, we tried to discover new thieno[2,3-d]pyrimidine derivatives "5a-o". Results from the screening on A549 and MCF7 cancer cell lines revealed that compounds 5j and 5k showed two-digit nanomolar with appropriate safety towards the WI-38 cell line. The best molecules, 5j and 5k, were subjected to γ-radiation, and their cytotoxic efficacy didn't change after irradiation, demonstrating that not having to use it avoided its side effects. Compounds 5j and 5k demonstrated the highest inhibition when their potency was tested as dual inhibitors on EGFR 67 and 41 nM, respectively, and STAT3 5.52 and 3.34 nM, respectively, proved with in silico molecular docking and dynamic simulation. In light of the results presented above, the capacity of both powerful compounds to alter the cell cycle and initiate the apoptotic process in breast cancer MCF7 cells was investigated. Caspase-8, Bcl-2, Bax and Caspase-9 apoptotic indicators were studied.
Assuntos
Antineoplásicos , Receptores ErbB , Fator de Transcrição STAT3 , Humanos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/antagonistas & inibidores , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Relação Estrutura-AtividadeRESUMO
Hepatocellular carcinoma (HCC) is a challenging and very fatal liver cancer. The signal transducer and activator of transcription 3 (STAT3) pathway is a crucial regulator of tumor development and are ubiquitously active in HCC. Therefore, targeting STAT3 has emerged as a promising approach for preventing and treating HCC. Various natural bioactive compounds (NBCs) have been proven to target STAT3 and have the potential to prevent and treat HCC as STAT3 inhibitors. Numerous kinds of STAT3 inhibitors have been identified, including small molecule inhibitors, peptide inhibitors, and oligonucleotide inhibitors. Due to the undesirable side effects of the conventional therapeutic drugs against HCC, the focus is shifted to NBCs derived from plants and other natural sources. NBCs can be broadly classified into the categories of terpenes, alkaloids, carotenoids, and phenols. Most of the compounds belong to the family of terpenes, which prevent tumorigenesis by inhibiting STAT3 nuclear translocation. Further, through STAT3 inhibition, terpenes downregulate matrix metalloprotease 2 (MMP2), matrix metalloprotease 9 (MMP9) and vascular endothelial growth factor (VEGF), modulating metastasis. Terpenes also suppress the anti-apoptotic proteins and cell cycle markers. This review provides comprehensive information related to STAT3 abrogation by NBCs in HCC with in vitro and in vivo evidences.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Terpenos/farmacologia , Terpenos/uso terapêutico , Metaloproteases/metabolismoRESUMO
The Janus kinase/signal transducer and activator of the transcription 3 (JAK/STAT3) signaling pathway controls multiple biological processes, including cell survival, proliferation, and differentiation. Abnormally activated STAT3 signaling promotes tumor cell growth, proliferation, and survival, as well as tumor invasion, angiogenesis, and immunosuppression. Hence, JAK/STAT3 signaling has been considered a promising target for antitumor therapy. In this study, a number of ageladine A derivative compounds were synthesized. The most effective of these was found to be compound 25. Our results indicated that compound 25 had the greatest inhibitory effect on the STAT3 luciferase gene reporter. Molecular docking results showed that compound 25 could dock into the STAT3 SH2 structural domain. Western blot assays demonstrated that compound 25 selectively inhibited the phosphorylation of STAT3 on the Tyr705 residue, thereby reducing STAT3 downstream gene expression without affecting the expression of the upstream proteins, p-STAT1 and p-STAT5. Compound 25 also suppressed the proliferation and migration of A549 and DU145 cells. Finally, in vivo research revealed that 10 mg/kg of compound 25 effectively inhibited the growth of A549 xenograft tumors with persistent STAT3 activation without causing significant weight loss. These results clearly indicate that compound 25 could be a potential antitumor agent by inhibiting STAT3 activation.
Assuntos
Janus Quinases , Transdução de Sinais , Humanos , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Janus Quinases/metabolismo , Fosforilação , Fator de Transcrição STAT3/metabolismo , Proliferação de Células , Ensaios Antitumorais Modelo de Xenoenxerto , ApoptoseRESUMO
STAT3 is a promising therapeutic target for the treatment of gastric cancer, which is one of the most common solid tumors worldwide. In the previous works, we discovered a series of novel STAT3 inhibitors bearing an imidazo[1,2-a] pyridine scaffold. In order to improve the metabolic stability of these compounds, herein we performed a systematic structural optimization leading to a bioactive inhibitor 42, which demonstrated significant effects on inhibiting the growth, migration and invasion of human gastric cancer cells lines (AGS and MGC-803). Meanwhile, it was able to block the phosphorylation and dimerization of STAT3 at low micromolar concentration. Furthermore, compound 42 obviously suppressed tumor growth in MGC-803 derived xenograft mouse model, suggesting that it deserves further exploration as a promising anti-cancer agent for advanced gastric cancer.
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Neoplasias Gástricas , Humanos , Camundongos , Animais , Neoplasias Gástricas/patologia , Proliferação de Células , Linhagem Celular Tumoral , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Piridinas/farmacologia , Piridinas/uso terapêuticoRESUMO
The superimposition of the X-ray complexes of cyclohexanediones (i.e., TUB015), described by our research group, and nocodazole, within the colchicine binding site of tubulin provided an almost perfect overlap of both ligands. This structural information led us to propose hybrids of TUB015 and nocodazole using a salicylanilide core structure. Interestingly, salicylanilides, such as niclosamide, are well-established signal transducers and activators of transcription (STAT3) inhibitors with anticancer properties. Thus, different compounds with this new scaffold have been synthesized with the aim to identify compounds inhibiting tubulin polymerization and/or STAT3 signaling. As a result, we have identified new salicylanilides (6 and 16) that showed significant antiproliferative activity against a panel of cancer cells. Both compounds were able to reduce the levels of p-STAT3Tyr705 without affecting the total expression of STAT3. While compound 6 inhibited tubulin polymerization and arrested the cell cycle of DU145 cells at G2/M, similar to TUB015, compound 16 showed a more potent effect on inhibiting STAT3 phosphorylation and arrested the cell cycle at G1/G0, similar to niclosamide. In both cases, no toxicity towards PBMC cells was detected. Thus, the salicylanilides described here represent a new class of antiproliferative agents affecting tubulin polymerization and/or STAT3 phosphorylation.
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Patients with BRAFV600E-mutant melanoma are effectively treated with the BRAF-inhibiting drug, vemurafenib, but soon develop drug resistance, limiting vemurafenib's therapeutic efficacy. Constitutive activation of STAT3 in cancer cells and immune cells in the tumor microenvironment (TME) is a crucial contributor to the development of drug resistance and immune evasion in most cancers. Here, we investigated the antitumor efficacy and TME remodeling by APTSTAT3-9R, a cell-permeable STAT3 inhibitory peptide, as a strategy to treat vemurafenib-resistant melanoma. We found that vemurafenib-resistant melanoma remodels into immunosuppressive TME by increasing the expression of specific chemokines to facilitate the infiltration of immunosuppressive immune cells, such as myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). Intratumoral treatment of APTSTAT3-9R led to a reduction in the population of MDSCs and TAMs, while increasing infiltration of cytotoxic T lymphocytes in the TME. Moreover, combination therapy with APTSTAT3-9R and an anti-PD-1 antibody enhanced significant suppression of tumor growth by decreasing infiltration of these immunosuppressive immune cells while increasing the infiltration and cytotoxicity of CD8+ T cells. These findings suggest that combined blockade of STAT3 and PD-1 signaling pathways may be an effective treatment option for overcoming poor therapeutic outcomes associated with drug-resistant BRAF-mutant melanoma.
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Triple-negative breast cancer lacks an expression of ER, PR, and Her-2, has a poor prognosis, and there are no target therapies available. Therapeutic options to treat TNBC are limited and urgently needed. Strong evidence indicates that molecular signaling pathways have a significant function to regulate biological mechanisms and their abnormal expression endows with the development of cancer. PIM kinase is overexpressed in various human cancers including TNBC which is regulated by various signaling pathways that are crucial for cancer cell proliferation and survival and also make PIM kinase as an attractive drug target. One of the targets of the STAT3 signaling pathway is PIM1 that plays a key role in tumor progression and transformation. In this review, we accumulate the current scenario of the PIM-STAT3 axis that provides insights into the PIM1 and STAT3 inhibitors which can be developed as potential co-inhibitors as prospective anticancer agents.
Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/metabolismoRESUMO
In our continued SAR study efforts, a series of O-alkylamino-tethered salicylamide derivatives with various amino acid linkers has been designed, synthesized, and biologically evaluated as potent anticancer agents. Five selected compounds with different representative chemical structures were found to show broad anti-proliferative activities, effective against all tested ER-positive breast cancer (BC) and triple-negative breast cancer (TNBC) cell lines with low micromolar IC50 values. Among these compounds, compound 9a (JMX0293) maintained good potency against MDA-MB-231 cell line (IC50 = 3.38 ± 0.37 µM) while exhibiting very low toxicity against human non-tumorigenic breast epithelial cell line MCF-10A (IC50 > 60 µM). Further mechanistic studies showed that compound 9a could inhibit STAT3 phosphorylation and contribute to apoptosis in TNBC MDA-MB-231 cells. More importantly, compound 9a significantly suppressed MDA-MB-231 xenograft tumor growth in vivo without significant toxicity, indicating its great potential as a promising anticancer drug candidate for further clinical development.
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Antineoplásicos , Neoplasias de Mama Triplo Negativas , Aminoácidos/farmacologia , Aminoácidos/uso terapêutico , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Salicilamidas , Relação Estrutura-Atividade , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
The Signal Transducer and Activator of Transcription 3 (STAT3) protein is encoded on chromosome 17q21. The SH2 and the DNA binding domains are critical structural components of the protein, together with tyrosine and serine residues that initiate phosphorylation. STAT3 interacts with DNA directly and functions in cells as both a signal transducer and a transcription factor. Its cytoplasmic activation results in dimerisation and nuclear translocation, where it is involved in the transcription of a large number of target genes. STAT3 is hyperactive in cancer cells as a result of upstream STAT3 mutations or enhanced cytokine production in the tumour environment. The STAT3 signalling pathway promotes many hallmarks of carcinogenesis and metastasis, including enhanced cell proliferation and survival, as well as migration and invasion into the extracellular matrix. Recent investigations into novel STAT3-based therapies describe a range of innovative approaches, such as the use of novel oligonucleotide drugs. These limit STAT3 binding to its target genes by attaching to SH2 and DNA-binding domains. Yet, despite these significant steps in understanding the underpinning mechanisms, there are currently no therapeutic agents that addresses STAT3 signalling in a clinically relevant manner.
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Neoplasias , Fator de Transcrição STAT3 , Regulação da Expressão Gênica , Humanos , Neoplasias/genética , Fosforilação , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/fisiologiaRESUMO
Background: STAT3 is a pro-oncogenic transcription factor. Pyrimethamine (PYM) is a STAT3 inhibitor that suppresses the proliferation of some cancer cells through downregulation of STAT3 target proteins. Methodology & Results: We have used structure-based tools to design novel PYM-based compounds. Intracellular target validation studies revealed that representative compounds 11b-d and 15a downregulate STAT3 downstream proteins and inhibit STAT3 DNA binding domain (DBD). Relative to PYM, a cohort of these compounds are >100-fold more cytotoxic to cancer cells with constitutively active (high pSTAT3) and basal (low pSTAT3) STAT3 signaling, suggesting that STAT3 DBD inhibition is deleterious to the proliferation of cancer cells with low and high pSTAT3 levels. Conclusion: These are promising leads for further preclinical evaluation as therapeutic agents for STAT3-dependent cancers.
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DNA/química , Desenho de Fármacos , Pirimetamina/química , Fator de Transcrição STAT3/antagonistas & inibidores , Sítios de Ligação , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Domínios Proteicos , Pirimetamina/metabolismo , Pirimetamina/farmacologia , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
In developed countries, colorectal cancer (CRC) is the fourth most common cancer and the second leading cause of malignant-related deaths. CRC is treatable cancer when diagnosed early; however, diagnosis at the advanced stage is associated with a poor prognosis. Although chemotherapy is generally very promising, STAT3 protein which is overexpressed and persistently activated in CRC cells is observed to be the major contributor of chemoresistance development. It has been shown to play a prominent and pathogenic role in CRC initiation, progression, and metastasis. While over the past few years, research has been focused on STAT3 which is expressed at the center of various oncogenic pathways. This review is a discussion of the oncogenic role of STAT3 in CRC and potential therapeutic STAT3 inhibitors and analogs used to control and treat CRC.
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Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Terapia de Alvo Molecular , Fator de Transcrição STAT3/antagonistas & inibidores , Animais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , HumanosRESUMO
There is an urgent need for new treatment options in metastatic drug-resistant prostate cancer. Combining immunotherapy with other targeted therapies may be an effective strategy for advanced prostate cancer. In the present study, we sought to investigate to enhance the efficacy of anti-CTLA-4 therapy against prostate cancer by the combination with STAT3 inhibition.Male C57BL6 mice were subcutaneously inoculated with the murine prostate cancer cell line RM-1. Tumor progression was monitored following treatment with vehicle, the small molecule STAT3 inhibitor GPB730, anti-CTLA-4 or GPB730 + anti-CTLA-4. Treatment with anti-CTLA-4 or anti-CTLA-4 + GPB730 significantly inhibited tumor growth and enhanced survival compared to vehicle. Combining anti-CTLA-4 treatment with GPB730 resulted in a significantly prolonged survival compared to anti-CTLA-4 alone. GPB730 significantly increased infiltration of CD45 + cells in tumors of anti-CTLA-4-treated mice compared to anti-CTLA-4 alone. The levels of tumor-infiltrating Tregs were significantly decreased and the CD8:Treg ratio significantly increased by GPB730 treatment in combination with anti-CTLA-4 compared to anti-CTLA-4 alone. Immunohistochemical analysis showed a significant increase in CD45-positive cells in anti-CTLA-4 and anti-CTLA-4 + GPB730-treated tumors compared to vehicle or GPB730 monotherapy. Plasma levels of IL10 were significantly increased by anti-CTLA-4 compared to vehicle but no increase was observed when combining anti-CTLA-4 with GPB730.In conclusion, STAT3 inhibition by GPB730 enhances the antitumoral activity of anti-CTLA-4 and decreases the intratumoral Treg frequency in a prostate cancer mouse model. These results support the combination of STAT3 inhibition with anti-CTLA-4 therapy to increase clinical responses in patients with prostate cancer.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias de Próstata Resistentes à Castração/patologia , Fator de Transcrição STAT3/antagonistas & inibidores , Animais , Lactonas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Signal transducer and activator of transcription 3 (STAT3) has been confirmed as an attractive therapeutic target for cancer therapy. Herein, we designed and synthesized a series of N-substituted Sulfamoylbenzamide STAT3 inhibitors based on small-molecule STAT3 inhibitor Niclosamide. Compound B12, the best active compound of this series, was identified as an inhibitor of IL-6/STAT3 signaling with an IC50 of 0.61-1.11 µM in MDA-MB-231, HCT-116 and SW480 tumor cell lines with STAT3 overexpression, by inhibiting the phosphorylation of STAT3 of Tyr705 residue and the expression of STAT3 downstream genes, inducing apoptosis and inhibiting the migration of cancer cells. Furthermore, in vivo study revealed that compound B12 suppressed the MDA-MB-231 xenograft tumor growth in nude mice at the dose of 30 mg/kg (i.g.), which has better antitumor activity than the positive control Niclosamide. More importantly, B12 is an orally bioavailable anticancer agent as a promising candidate for further development.
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Benzamidas/farmacologia , Descoberta de Drogas , Niclosamida/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Benzamidas/síntese química , Benzamidas/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Niclosamida/síntese química , Niclosamida/química , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Drug repurposing is a valuable approach in delivering new cancer therapeutics rapidly into the clinic. Existing safety and patient tolerability data for drugs already in clinical use represent an untapped resource in terms of identifying therapeutic agents for off-label protein targets. The multicellular effects of STAT3 mediated by a range of various upstream signaling pathways make it an attractive therapeutic target with utility in a range of diseases including cancer, and has led to the development of a variety of STAT3 inhibitors. Moreover, heightened STAT3 transcriptional activation in tumor cells and within the cells of the tumor microenvironment contribute to disease progression. Consequently, there are many STAT3 inhibitors in preclinical development or under evaluation in clinical trials for their therapeutic efficacy predominantly in inflammatory diseases and cancer. Despite these advances, many challenges remain in ultimately providing STAT3 inhibitors to patients as cancer treatments, highlighting the need not only for a better understanding of the mechanisms associated with STAT3 activation, but also how various pharmaceutical agents suppress STAT3 activity in various cancers. In this review we discuss the importance of STAT3-dependent functions in cancer, review the status of compounds designed as direct-acting STAT3 inhibitors, and describe some of the strategies for repurposing of drugs as STAT3 inhibitors for cancer therapy.