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BACKGROUND: Treatment with regorafenib, a multiple-kinase inhibitor, to manage metastatic colorectal cancers (mCRCs) shows a modest improvement in overall survival but is associated with severe toxicities. Thus, to reduce regorafenib-induced toxicity, we used regorafenib at low concentration along with a dual JAK/HDAC small-molecule inhibitor (JAK/HDACi) to leverage the advantages of both JAK and HDAC inhibition to enhance antitumor activity. The therapeutic efficacy and safety of the combination treatment was evaluated with CRC models. METHODS: The cytotoxicity of JAK/HDACi, regorafenib, and their combination were tested with normal colonic and CRC cells exhibiting various genetic backgrounds. Kinomic, ATAC-seq, RNA-seq, cell cycle, and apoptosis analyses were performed to evaluate the cellular functions/molecular alterations affected by the combination. Efficacy of the combination was assessed using patient-derived xenograft (PDX) and experimental metastasis models of CRC. To evaluate the interplay between tumor, its microenvironment, and modulation of immune response, MC38 syngeneic mice were utilized. RESULTS: The combination therapy decreased cell viability; phosphorylation of JAKs, STAT3, EGFR, and other key kinases; and inhibited deacetylation of histone H3K9, H4K8, and alpha tubulin proteins. It induced cell cycle arrest at G0-G1 phase and apoptosis of CRC cells. Whole transcriptomic analysis showed that combination treatment modulated molecules involved in apoptosis, extracellular matrix-receptor interaction, and focal adhesion pathways. It synergistically reduces PDX tumor growth and experimental metastasis, and, in a syngeneic mouse model, the treatment enhances the antitumor immune response as evidenced by higher infiltration of CD45 and cytotoxic cells. Pharmacokinetic studies showed that combination increased the bioavailability of regorafenib. CONCLUSIONS: The combination treatment was more effective than with regorafenib or JAK/HDACi alone, and had minimal toxicity. A clinical trial to evaluate this combination for treatment of mCRCs is warranted.
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Neoplasias Colorretais , Inibidores de Histona Desacetilases , Compostos de Fenilureia , Piridinas , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Humanos , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/administração & dosagem , Animais , Camundongos , Piridinas/farmacologia , Piridinas/administração & dosagem , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Inibidores de Histona Desacetilases/administração & dosagem , Metástase Neoplásica , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Sinergismo Farmacológico , Linhagem Celular Tumoral , Feminino , Apoptose/efeitos dos fármacos , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/administração & dosagem , Inibidores de Janus Quinases/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Thyroid hormone receptor-interacting protein 13 (TRIP13) is involved in cancer progression, but its role in pancreatic ductal adenocarcinoma (PDAC) is unknown. Thus, we assessed the expression, functional role, and mechanism of action of TRIP13 in PDAC. We further examined the efficacy of TRIP13 inhibitor, DCZ0415, alone or in combination with gemcitabine on malignant phenotypes, tumor progression, and immune response. We found that TRIP13 was overexpressed in human PDACs relative to corresponding normal pancreatic tissues. TRIP13 knockdown or treatment of PDAC cells with DCZ0415 reduced proliferation and colony formation, and induced G2/M cell cycle arrest and apoptosis. Additionally, TRIP13 knockdown or targeting with DCZ0415 reduced the migration and invasion of PDAC cells by increasing E-cadherin and decreasing N-cadherin and vimentin. Pharmacologic targeting or silencing of TRIP13 also resulted in reduce expression of FGFR4 and STAT3 phosphorylation, and downregulation of the Wnt/ß-catenin pathway. In immunocompromised mouse models of PDAC, knockdown of TRIP13 or treatment with DCZ0415 reduced tumor growth and metastasis. In an immunocompetent syngeneic PDAC model, DCZ0415 treatment enhanced the immune response by lowering expression of PD1/PDL1, increasing granzyme B/perforin expression, and facilitating infiltration of CD3/CD4 T-cells. Further, DCZ0415 potentiated the anti-metastatic and anti-tumorigenic activities of gemcitabine by reducing proliferation and angiogenesis and by inducing apoptosis and the immune response. These preclinical findings show that TRIP13 is involved in PDAC progression and targeting of TRIP13 augments the anticancer effect of gemcitabine.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , ATPases Associadas a Diversas Atividades Celulares/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , ATPases Associadas a Diversas Atividades Celulares/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Gencitabina , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismoRESUMO
Pancreatic cancer (PanCa) is one of the most aggressive forms of cancer and its incidence rate is continuously increasing every year. It is expected that by 2030, PanCa will become the 2nd leading cause of cancer-related deaths in the United States due to the lack of early diagnosis and extremely poor survival. Despite great advancements in biomedical research, there are very limited early diagnostic modalities available for the early detection of PanCa. Thus, understanding of disease biology and identification of newer diagnostic and therapeutic modalities are high priority. Herein, we have utilized high dimensional omics data along with some wet laboratory experiments to decipher the expression level of hormone receptor interactor 13 (TRIP13) in various pathological staging including functional enrichment analysis. The functional enrichment analyses specifically suggest that TRIP13 and its related oncogenic network genes are involved in very important patho-physiological pathways. These analyses are supported by qPCR, immunoblotting and IHC analysis. Based on our study we proposed TRIP13 as a novel molecular target for PanCa diagnosis and therapeutic interventions. Overall, we have demonstrated a crucial role of TRIP13 in pathogenic events and progression of PanCa through applied integrated computational biology approaches.
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Purpose: Although there is an established role for microbiome dysbiosis in the pathobiology of colorectal cancer (CRC), CRC patients of various race/ethnicities demonstrate distinct clinical behaviors. Thus, we investigated microbiome dysbiosis in Egyptian, African American (AA), and European American (EA) CRC patients. Patients and methods: CRCs and their corresponding normal tissues from Egyptian (n = 17) patients of the Alexandria University Hospital, Egypt, and tissues from AA (n = 18) and EA (n = 19) patients at the University of Alabama at Birmingham were collected. DNA was isolated from frozen tissues, and the microbiome composition was analyzed by 16S rRNA sequencing. Differential microbial abundance, diversity, and metabolic pathways were identified using linear discriminant analysis (LDA) effect size analyses. Additionally, we compared these profiles with our previously published microbiome data derived from Kenyan CRC patients. Results: Differential microbiome analysis of CRCs across all racial/ethnic groups showed dysbiosis. There were high abundances of Herbaspirillum and Staphylococcus in CRCs of Egyptians, Leptotrichia in CRCs of AAs, Flexspiria and Streptococcus in CRCs of EAs, and Akkermansia muciniphila and Prevotella nigrescens in CRCs of Kenyans (LDA score >4, adj. p-value <0.05). Functional analyses showed distinct microbial metabolic pathways in CRCs compared to normal tissues within the racial/ethnic groups. Egyptian CRCs, compared to normal tissues, showed lower l-methionine biosynthesis and higher galactose degradation pathways. Conclusions: Our findings showed altered mucosa-associated microbiome profiles of CRCs and their metabolic pathways across racial/ethnic groups. These findings provide a basis for future studies to link racial/ethnic microbiome differences with distinct clinical behaviors in CRC.
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Because survival of patients with metastatic colorectal cancer remain poor, there is an urgent need to identify potential novel druggable targets that are associated with colorectal cancer progression. One such target, basic leucine zipper and W2 domains 2 (BZW2), is involved in regulation of protein translation, and its overexpression is associated with human malignancy. Thus, we investigated the expression and regulation of BZW2, assessed its role in activation of WNT/ß-catenin signaling, identified its downstream molecules, and demonstrated its involvement in metastasis of colorectal cancer. In human colorectal cancers, high mRNA and protein expression levels of BZW2 were associated with tumor progression. BZW2-knockdown reduced malignant phenotypes, including cell proliferation, invasion, and spheroid and colony formation. BZW2-knockdown also reduced tumor growth and metastasis; conversely, transfection of BZW2 into BZW2 low-expressing colorectal cancer cells promoted malignant features, including tumor growth and metastasis. BZW2 expression was coordinately regulated by microRNA-98, c-Myc, and histone methyltransferase enhancer of zeste homolog 2 (EZH2). RNA sequencing analyses of colorectal cancer cells modulated for BZW2 identified P4HA1 and the long noncoding RNAs, MALAT1 and NEAT1, as its downstream targets. Further, BZW2 activated the Wnt/ß-catenin signaling pathway in colorectal cancers expressing wild-type ß-catenin. In sum, our study suggests the possibility of targeting BZW2 expression by inhibiting EZH2 and/or c-Myc. IMPLICATIONS: FDA-approved small-molecule inhibitors of EZH2 can indirectly target BZW2 and because BZW2 functions as an oncogene, these inhibitors could serve as therapeutic agents for colorectal cancer.
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Neoplasias Colorretais , MicroRNAs , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Proliferação de Células/genética , Via de Sinalização Wnt/genética , Transfecção , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , MicroRNAs/genéticaRESUMO
Background: Colorectal cancer (CRC) is the fifth most diagnosed cancer in Sub-Saharan Africa. In Kenya, CRC incidence rates tripled from 1997 to 2017. In the Moi Teaching and Referral Hospital, Moi University, there has been an increase in CRC cases, notably for younger patients. A suggested pathobiology for this increase is gut microbiome dysbiosis. Since, for the Kenyan CRC patient population, microbiome studies are rare, there is a need for a better understanding of how microbiome dysbiosis influences CRC epidemiology in Kenya. In this single-center study, the focus was on profiling the gut microbiome of Kenyan CRC patients and healthy volunteers and evaluating associations between microbiome profiles and the age of CRC patients. Methods: The gut mucosa-associated microbiome of 18 CRC patients and 18 healthy controls were determined by 16S rRNA sequencing and analyzed for alpha and beta diversity, differential abundance, and microbial metabolic profiling. Results: Alpha diversity metrics showed no significant differences, but beta diversity metrics showed dissimilarities in the microbial communities between CRC patients and healthy controls. The most underrepresented species in the CRC group were Prevotella copri (P. copri) and Faecalibacterium prausnitzii (F. prausnitzii), although Bacteroides fragilis (B. fragilis) and Prevotella nigrescens were overrepresented (linear discriminant analysis, LDA score >2, P<0.05). Also, for CRC patients, significant metagenomic functional alterations were evident in microbial glutamate metabolic pathways (L-glutamate degradation VIII was enriched, and L-glutamate and L-glutamine biosynthesis were diminished) (P<0.05, log2 Fold Change >1). Moreover, the microbiome composition was different for patients under 40 years of age compared to older patients (LDA score >2, P<0.05). Conclusions: Microbiome and microbial metabolic profiles of CRC patients are different from those of healthy individuals. CRC microbiome dysbiosis, particularly P. copri and F. prausnitzii depletion and glutamate metabolic alterations, are evident in Kenyan CRC patients.
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Reliable preclinical models are needed for screening new cancer drugs. Thus, we developed an improved 3D tumor organoid model termed "organoid raft cultures" (ORCs). Development of ORCs involved culturing tumors ex vivo on collagen beds (boats) with grid supports to maintain their morphological structure. The ORCs were developed from patient-derived xenografts (PDXs) of colon cancers excised from immune-deficient mice (NOD/SCID/IL2Rgammanull). We utilized these new models to evaluate the efficacy of an investigational drug, Navitoclax (ABT-263). We tested the efficacy of ABT-263, an inhibitor of BCL-2 family proteins, in these ORCs derived from a PDX that showed high expression of antiapoptotic BCL2 family proteins (BCL-2, BCL-XL, and BCL-W). Hematoxylin and eosin staining evaluation of PDXs and corresponding ORCs indicated the retention of morphological and other histological integrity of ORCs. ORCs treated with ABT-263 showed decreased expression of antiapoptotic proteins (BCL2, BCL-XL and BCL-W) and increased proapoptotic proteins (BAX and PUMA), with concomitant activation of caspase 3. These studies support the usefulness of the ORCs, developed from PDXs, as an alternative to PDXs and as faster screening models.
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Neoplasias , Organoides , Camundongos , Humanos , Animais , Organoides/metabolismo , Camundongos SCID , Camundongos Endogâmicos NOD , Navios , Xenoenxertos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína bcl-X/metabolismo , Modelos Animais de Doenças , Neoplasias/patologia , Proteínas Reguladoras de ApoptoseRESUMO
Background: For several cancers, including those of the breast, young age at diagnosis is associated with an adverse prognosis. Although this effect is often attributed to heritable mutations such as BRCA1/2, the relationship between pathologic features, young age of onset, and prognosis for breast cancer remains unclear. In the present study, we highlight links between age of onset and lymph node metastasis (NM) in US women with breast cancer. Methods: Case listings from Surveillance, Epidemiology, and End Result (SEER) 18 registry data for women with breast cancer, which include information on race, were used. NM and its associated outcomes were evaluated for a subset of women with receptor subtype information and then compared against a larger, pre-subtype validation set of data from the same registry. Age of diagnosis was a 5-category variable; under 40 years, 40-49 years, 50-59 years, 60-69 years and 70+ years. Univariate and adjusted multivariate survival models were applied to both sets of data. Results: As determined with adjusted logistic regression models, women under 40 years old at diagnosis had 1.55 times the odds of NM as women 60-69 years of age. The odds of NM for (HR = hormone receptor) HR+/HER2+, HR-/HER2+, and triple-negative breast cancer subtypes were significantly lower than those for HR+/HER2-. In subtype-stratified adjusted models, age of diagnosis had a consistent trend of decreasing odds of NM by age category, most noticeable for HR+ subtypes of luminal A and B. Univariate 5-year survival by age was worst for women under 40 years, with NM attributable for 49% of the hazard of death from cancer in adjusted multivariate models. Conclusions: Lymph node metastasis is age-dependent, yet not all molecular subtypes are clearly affected by this relationship. For <40-yr-old women, NM is a major cause for shorter survival. When stratified by subtype, the strongest associations were in HR+ groups, suggesting a possible hormonal connection between young age of breast cancer onset and NM.
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Thyroid receptor-interacting protein 13 (TRIP13), a protein of the AAA-ATPase family, is upregulated in various human cancers, including colorectal cancer (CRC). This study focused on the inhibition of TRIP13-induced CRC progression and signalling by DCZ0415, a small molecule targeting TRIP13. It demonstrated potent antitumour activity in TRIP13-deregulated cancer cell lines, regardless of their p53, KRAS, BRAF, epidermal growth factor receptor or microsatellite instability status. The treatment of CRC cells with DCZ0415 resulted in decreased cell proliferation, induced cell cycle arrest in the G2-M phase and increased apoptosis. DCZ0415 diminished xenograft tumour growth and metastasis of CRC in immunocompromised mice. DCZ0415 reduced expression of fibroblast growth factor receptor 4 (FGFR4), signal transducer and activator of transcription 3 (STAT3), and proteins associated with the epithelial-mesenchymal transition and nuclear factor kappa B (NF-κB) pathways in cells and xenografts exhibiting high expression of TRIP13. Additionally, DCZ0415 decreased cyclin D1, ß-catenin and T-cell factor 1, leading to the inactivation of the Wnt/ß-catenin pathway. In a syngeneic CRC model, DCZ0415 treatment induced an immune response by decreasing PD1 and CTLA4 levels and increasing granzyme B, perforin and interferon gamma. In sum, DCZ04145 inhibits the TRIP13-FGFR4-STAT3 axis, inactivates NF-κB and Wnt/ß-catenin signalling, activates antitumour immune response and reduces the progression and metastasis of CRC. This study provides a rationale to evaluate DCZ0415 clinically for the treatment of a subset of CRCs that exhibit dysregulated TRIP13 and FGFR4.
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Neoplasias Colorretais , beta Catenina , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , NF-kappa B/metabolismo , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Fator de Transcrição STAT3/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismoRESUMO
Melanoma is the most aggressive skin cancer. Its aggressiveness is most commonly attributed to ERK pathway mutations leading to constitutive signaling. Though initial tumor regression results from targeting this pathway, resistance often emerges. Interestingly, interrogation of the NCI-60 database indicates high growth hormone receptor (GHR) expression in melanoma cell lines. To further characterize melanoma, we tested responsiveness to human growth hormone (GH). GH treatment resulted in GHR signaling and increased invasion and migration, which was inhibited by a GHR monoclonal antibody (mAb) antagonist in WM35, SK-MEL 5, SK-MEL 28 and SK-MEL 119 cell lines. We also detected GH in the conditioned medium (CM) of human melanoma cell lines. GHR, JAK2 and STAT5 were basally phosphorylated in these cell lines, consistent with autocrine/paracrine GH production. Together, our results suggest that melanomas are enriched in GHR and produce GH that acts in an autocrine/paracrine manner. We suggest that GHR may constitute a therapeutic target in melanoma.
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Skin cancer is the most common type of cancer with increasing incidence rate and public health burden. Solar ultraviolet (UV) radiation causes an array of damaging cellular and molecular events that eventually lead to the development of skin cancer. Despite increased awareness about sun protection, the exposure rate remains high with less than 15% of men and 30% of women using sunscreen on a regular basis. Therefore, there is an imperative need for the development of novel preventive approaches. Skin cancer chemoprevention using phytochemicals either as dietary supplements or by topical applications has gained considerable attention due to their low toxicity, availability, and anticarcinogenic properties. Tea, the second most commonly consumed beverage in the world, is a rich source of promising phytochemicals known as polyphenols. In this review, we discuss the findings of various in vitro, in vivo and human studies signifying the chemopreventive effects of tea polyphenols against UVB-induced skin cancer. This is accomplished by exploring the role of tea polyphenols in DNA repair, inflammation, oxidative stress, signaling pathways, and epigenetics. Finally, this review discusses a variety of innovative delivery methods that enhance the photochemopreventive effects of tea polyphenols against skin cancer.
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Reparo do DNA/efeitos dos fármacos , Polifenóis/farmacologia , Neoplasias Cutâneas/prevenção & controle , Chá , Apoptose/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Humanos , Inflamação/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/etiologia , Raios Ultravioleta/efeitos adversosRESUMO
Cancer is the second leading cause of death in the United States, and those who survive cancer may experience lasting difficulties, including treatment side effects, as well as physical, cognitive, and psychosocial struggles. Naturally-occurring agents from dietary fruits and vegetables have received considerable attention for the prevention and treatment of cancers. These natural agents are safe and cost efficient in contrast to expensive chemotherapeutic agents, which may induce significant side effects. The pomegranate (Punica granatum L.) fruit has been used for the prevention and treatment of a multitude of diseases and ailments for centuries in ancient cultures. Pomegranate exhibits strong antioxidant activity and is a rich source of anthocyanins, ellagitannins, and hydrolysable tannins. Studies have shown that the pomegranate fruit as well as its juice, extract, and oil exert anti-inflammatory, anti-proliferative, and anti-tumorigenic properties by modulating multiple signaling pathways, which suggest its use as a promising chemopreventive/chemotherapeutic agent. This review summarizes preclinical and clinical studies highlighting the role of pomegranate in prevention and treatment of skin, breast, prostate, lung, and colon cancers.
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Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Lythraceae/química , Neoplasias , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Anti-Inflamatórios/farmacologia , Proliferação de Células/efeitos dos fármacos , Quimioprevenção , Frutas/metabolismo , Humanos , Neoplasias/dietoterapia , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Transdução de Sinais/efeitos dos fármacosRESUMO
Ultraviolet (UV) exposure has an array of damaging effects and is the main cause of skin cancer in humans. Nonmelanoma skin cancer (NMSC), including basal cell carcinoma and squamous cell carcinoma, is the most common type of cancer. Incidence of NMSC has increased due to greater UV radiation, increased life expectancy and other changes in lifestyle; the annual cost of skin cancer treatment in the United States has increased concurrently to around eight billion dollars. Because of these trends, novel approaches to skin cancer prevention have become an important area of research to decrease skin cancer morbidity and defray the costs associated with treatment. Chemoprevention aims to prevent or delay the development of skin cancer through the use of phytochemicals. Use of phytochemicals as chemopreventive agents has gained attention due to their low toxicity and anticarcinogenic properties. Phytochemicals also exhibit antioxidant, anti-inflammatory and antiproliferative effects which support their use as chemopreventive agents, particularly for skin cancer. Preclinical and human studies have shown that phytochemicals decrease UV-induced skin damage and photocarcinogenesis. In this review article, we discuss the selected phytochemicals that may prevent or delay UV-induced carcinogenesis and highlight their potential use for skin protection.
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Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Induzidas por Radiação/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Animais , Quimioprevenção , DNA/efeitos da radiação , Dano ao DNA/efeitos da radiação , Humanos , Inflamação/etiologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos da radiação , Pele/efeitos da radiação , Neoplasias Cutâneas/classificação , Raios Ultravioleta/efeitos adversosRESUMO
Melanoma is a cutaneous neoplastic growth of melanocytes with great potential to invade and metastasize, especially when not treated early and effectively. Epithelial-mesenchymal transition (EMT) is the process by which melanocytes lose their epithelial characteristics and acquire mesenchymal phenotypes. Mesenchymal protein expression increases the motility, invasiveness, and metastatic potential of melanoma. Many pathways play a role in promotion of mesenchymal protein expression including RAS/RAF/MEK/ERK, PI3K/AKT/mTOR, Wnt/ß-catenin, and several others. Downstream effectors of these pathways induce expression of EMT transcription factors including Snail, Slug, Twist, and Zeb that promote repression of epithelial and induction of mesenchymal character. Emerging research has demonstrated that a variety of small molecule inhibitors as well as phytochemicals can influence the progression of EMT and may even reverse the process, inducing re-expression of epithelial markers. Phytochemicals are of particular interest as supplementary treatment options because of their relatively low toxicities and anti-EMT properties. Modulation of EMT signaling pathways using synthetic small molecules and phytochemicals is a potential therapeutic strategy for reducing the aggressive progression of metastatic melanoma. In this review, we discuss the emerging pathways and transcription factor targets that regulate EMT and evaluate potential synthetic small molecules and naturally occurring compounds that may reduce metastatic melanoma progression.
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Melanoma/genética , Transição Epitelial-Mesenquimal , Humanos , Melanoma/patologia , Compostos Fitoquímicos , Transdução de SinaisRESUMO
Arsenicals are painful, inflammatory and blistering causing agents developed as chemical weapons in World War I/II. However, their large stockpiles still exist posing threat to public health. Phenylarsine oxide (PAO), a strong oxidant and a prototype arsenical is tested for its suitability to defining molecular mechanisms underlying arsenicals-mediated tissue injury. Topically applied PAO induces cutaneous erythema, edema and micro-blisters. These gross inflammatory responses were accompanied by the enhanced production of pro-inflammatory cytokines, ROS and unfolded protein response (UPR) signaling activation. To demonstrate the involvement of UPR in the pathobiology of these lesions, we employed chemical chaperone, 4-phenylbutyric acid (4-PBA) which attenuates UPR. 4-PBA significantly reduced PAO-induced inflammation and blistering. Similar to its effects in murine epidermis, a dose- and time-dependent upregulation of ROS, cytokines, UPR proteins (GRP78, p-PERK, p-eIF2α, ATF4 and CHOP) and apoptosis were observed in PAO-treated human skin keratinocytes NHEK and HaCaT. In addition, 4-PBA significantly restored these molecular alterations in these cells. Employing RNA interference (RNAi)-based approaches, CHOP was found to be a key regulator of these responses. These effects are similar to those manifested by lewisite suggesting that PAO could be used as a prototype of arsenicals to define the molecular pathogenesis of chemical injury.
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Arsenicais/imunologia , Edema/imunologia , Eritema/imunologia , Inflamação/imunologia , Queratinócitos/metabolismo , Fator de Transcrição CHOP/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Edema/induzido quimicamente , Chaperona BiP do Retículo Endoplasmático , Eritema/induzido quimicamente , Fator de Iniciação 2 em Eucariotos/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Inflamação/induzido quimicamente , Queratinócitos/patologia , Camundongos , Camundongos Knockout , Estresse Oxidativo , Receptor Patched-1/genética , Fenilbutiratos/metabolismo , RNA Interferente Pequeno/genética , Fator de Transcrição CHOP/genética , Resposta a Proteínas não DobradasRESUMO
Chronic inflammation is a prolonged and dysregulated immune response leading to a wide variety of physiological and pathological conditions such as neurological abnormalities, cardiovascular diseases, diabetes, obesity, pulmonary diseases, immunological diseases, cancers, and other life-threatening conditions. Therefore, inhibition of persistent inflammation will reduce the risk of inflammation-associated chronic diseases. Inflammation-related chronic diseases require chronic treatment without side effects. Use of traditional medicines and restricted diet has been utilized by mankind for ages to prevent or treat several chronic diseases. Bioactive dietary agents or "Nutraceuticals" present in several fruits, vegetables, legumes, cereals, fibers, and certain spices have shown potential to inhibit or reverse the inflammatory responses and several chronic diseases related to chronic inflammation. Due to safe, nontoxic, and preventive benefits, the use of nutraceuticals as dietary supplements or functional foods has increased in the Western world. Fisetin (3,3',4',7-tetrahydroxyflavone) is a dietary flavonoid found in various fruits (strawberries, apples, mangoes, persimmons, kiwis, and grapes), vegetables (tomatoes, onions, and cucumbers), nuts, and wine that has shown strong anti-inflammatory, anti-oxidant, anti-tumorigenic, anti-invasive, anti-angiogenic, anti-diabetic, neuroprotective, and cardioprotective effects in cell culture and in animal models relevant to human diseases. In this chapter, we discuss the beneficial pharmacological effects of fisetin against different pathological conditions with special emphasis on diseases related to chronic inflammatory conditions.
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Flavonoides/uso terapêutico , Animais , Doença Crônica , Diabetes Mellitus/prevenção & controle , Flavonoides/farmacologia , Flavonóis , Humanos , Doenças do Sistema Nervoso/prevenção & controle , Obesidade/prevenção & controle , Transdução de Sinais/efeitos dos fármacosRESUMO
Arsenic is a mitochondrial toxin, and its derivatives, such as arsenic trioxide (ATO), can trigger endoplasmic reticulum (ER) and the associated unfolded protein response (UPR). Here, we show that arsenic induction of the UPR triggers ATF4, which is involved in regulating this ER-mitochondrial crosstalk that is important for the molecular pathogenesis of arsenic toxicity. Employing ATF4+/+ and ATF4-/- MEFs, we show that ATO induces UPR and impairs mitochondrial integrity in ATF4+/+ MEF cells which is largely ablated upon loss of ATF4. Following ATO treatment, ATF4 activates NADPH oxidase by promoting assembly of the enzyme components Rac-1/P47phox/P67phox, which generates ROS/superoxides. Furthermore, ATF4 is required for triggering Ca++/calpain/caspase-12-mediated apoptosis following ATO treatment. The IP3R inhibitor attenuates Ca++/calpain-dependent apoptosis, as well as reduces m-ROS and MMP disruption, suggesting that ER-mitochondria crosstalk involves IP3R-regulated Ca++ signaling. Blockade of m-Ca++ entry by inhibiting m-VDAC reduces ATO-mediated UPR in ATF4+/+ cells. Additionally, ATO treatment leads to p53-regulated mitochondrial apoptosis, where p53 phosphorylation plays a key role. Together, these findings indicate that ATO-mediated apoptosis is regulated by both ER and mitochondria events that are facilitated by ATF4 and the UPR. Thus, we describe novel mechanisms by which ATO orchestrates cytotoxic responses involving interplay of ER and mitochondria.
Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Apoptose , Arsenicais/química , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , NADPH Oxidases/metabolismo , Óxidos/química , Fator 4 Ativador da Transcrição/genética , Animais , Trióxido de Arsênio , Cálcio/química , Linhagem Celular , Sobrevivência Celular , Estresse do Retículo Endoplasmático , Fibroblastos/metabolismo , Homeostase , Camundongos , Oxirredução , Fosforilação , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Superóxidos/metabolismoRESUMO
Lewisite is a potent arsenic-based chemical warfare agent known to induce painful cutaneous inflammation and blistering. Only a few modestly effective antidotes have so far been described in the literature. However, the discovery of effective antidotes for lewisite was hampered by the paucity of the exact molecular mechanism underlying its cutaneous pathogenesis. We investigated the molecular mechanism underlying lewisite-induced cutaneous blistering and inflammation and describe its novel antidotes. On the basis of our initial screening, we used a highly sensitive murine model that recapitulates the known human pathogenesis of arsenicals-induced cutaneous inflammation and blistering. Topically administered lewisite induced potent acute inflammation and microvesication in the skin of Ptch1(+/-)/SKH-1 mice. Even at a very low dose, lewisite up-regulates unfolded protein response signaling, inflammatory response, and apoptosis. These cutaneous lesions were associated with production of reactive oxygen species and extensive apoptosis of the epidermal keratinocytes. We confirmed that activation of reactive oxygen species-dependent unfolded protein response signaling is the underlying molecular mechanism of skin damage. Similar alterations were noticed in lewisite-treated cultured human skin keratinocytes. We discovered that chemical chaperone 4-phenyl butyric acid and antioxidant N-acetylcysteine, which significantly attenuate lewisite-mediated skin injury, can serve as potent antidotes. These data reveal a novel molecular mechanism underlying the cutaneous pathogenesis of lewisite-induced lesions. We also identified novel potential therapeutic targets for lewisite-mediated cutaneous injury.
Assuntos
Antídotos/farmacologia , Antioxidantes/farmacologia , Vesícula/tratamento farmacológico , Substâncias para a Guerra Química/efeitos adversos , Chaperonas Moleculares/farmacologia , Receptor Patched-1/genética , Acetilcisteína/farmacologia , Animais , Arsenicais/efeitos adversos , Vesícula/induzido quimicamente , Vesícula/patologia , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/patologia , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Pelados , Camundongos Endogâmicos C57BL , Receptor Patched-1/metabolismo , Fenilbutiratos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Melanoma claims approximately 80% of skin cancer-related deaths. Its life-threatening nature is primarily due to a propensity to metastasize. The prognosis for melanoma patients with distal metastasis is bleak, with median survival of six months even with the latest available treatments. The most commonly mutated oncogenes in melanoma are BRAF and NRAS accounting approximately 60% and 20% of cases, respectively. In malignant melanoma, accumulating evidence suggests that multiple signaling pathways are constitutively activated and play an important role in cell proliferation, cell survival, epithelial to mesenchymal transition, metastasis and resistance to therapeutic regimens. Phytochemicals are gaining considerable attention because of their low toxicity, low cost, and public acceptance as dietary supplements. Cell culture and animals studies have elucidated several cellular and molecular mechanisms by which phytochemicals act in the prevention and treatment of metastatic melanoma. Several promising phytochemicals, such as, fisetin, epigallocatechin-3-gallate, resveratrol, curcumin, proanthocyanidins, silymarin, apigenin, capsaicin, genistein, indole-3-carbinol, and luteolin are gaining considerable attention and found in a variety of fresh fruits, vegetables, roots, and herbs. In this review, we will discuss the preventive potential, therapeutic effects, bioavailability and structure activity relationship of these selected phytochemicals for the management of melanoma.