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1.
Arch Toxicol ; 95(5): 1779-1791, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674969

RESUMO

Crack cocaine users are simultaneously exposed to volatilized cocaine and to its main pyrolysis product, anhydroecgonine methyl ester (AEME). Although the neurotoxic effects of cocaine have been extensively studied, little is known about AEME or its combination. We investigated cell death processes using rat primary hippocampal cells exposed to cocaine (2 mM), AEME (1 mM) and their combination (C + A), after 1, 3, 6 and 12 h. Cocaine increased LC3 I after 6 h and LC3 II after 12 h, but reduced the percentage of cells with acid vesicles, suggesting failure in the autophagic flux, which activated the extrinsic apoptotic pathway after 12 h. AEME neurotoxicity did not involve the autophagic process; rather, it activated caspase-9 after 6 h and caspase-8 after 12 h leading to a high percentage of cells in early apoptosis. C + A progressively reduced the percentage of undamaged cells, starting after 3 h; it activated both apoptotic pathways after 6 h, and was more neurotoxic than cocaine and AEME alone. Also, C + A increased the phosphorylation of p62 after 12 h, but there was little difference in LC3 I or II, and a small percentage of cells with acid vesicles at all time points investigated. In summary, the present study provides new evidence for the neurotoxic mechanism and timing response of each substance alone and in combination, indicating that AEME is more than just a biological marker for crack cocaine consumption, as it may intensify and hasten cocaine neurotoxicity.


Assuntos
Cocaína/análogos & derivados , Animais , Cocaína/toxicidade , Cromatografia Gasosa-Espectrometria de Massas , Hipocampo , Neurônios , Síndromes Neurotóxicas , Pirólise , Ratos
2.
Pharmacol Res ; 159: 104998, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32535222

RESUMO

Indoleamine 2,3-dioxygenase (IDO) is associated with the progression of many types of tumors, including melanoma. However, there is limited information about IDO modulation on tumor cell itself and the effect of BRAF inhibitor (BRAFi) treatment and resistance. Herein, IDO expression was analyzed in different stages of melanoma development and progression linked to BRAFi resistance. IDO expression was increased in primary and metastatic melanomas from patients' biopsies, especially in the immune cells infiltrate. Using a bioinformatics approach, we also identified an increase in the IDO mRNA in the vertical growth and metastatic phases of melanoma. Using in silico analyses, we found that IDO mRNA was increased in BRAFi resistance. In an in vitro model, IDO expression and activity induced by interferon-gamma (IFNγ) in sensitive melanoma cells was decreased by BRAFi treatment. However, cells that became resistant to BRAFi presented random IDO expression levels. Also, we identified that treatment with the IDO inhibitor, 1-methyltryptophan (1-MT), was able to reduce clonogenicity for parental and BRAFi-resistant cells. In conclusion, our results support the hypothesis that the decreased IDO expression in tumor cells is one of the many additional outcomes contributing to the therapeutic effects of BRAFi. Still, the IDO production changeability by the BRAFi-resistant cells reiterates the complexity of the response arising from resistance, making it not possible, at this stage, to associate IDO expression in tumor cells with resistance. On the other hand, the maintenance of 1-MT off-target effect endorses its use as an adjuvant treatment of melanoma that has become BRAFi-resistant.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Vemurafenib/farmacologia , Linhagem Celular Tumoral , Bases de Dados Genéticas , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Melanoma/enzimologia , Melanoma/genética , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Triptofano/análogos & derivados , Triptofano/farmacologia
3.
Food Chem Toxicol ; 141: 111371, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32334110

RESUMO

NRAS-mutations arise in 15-20% of all melanomas and are associated with aggressive disease and poor prognosis. Besides, the treatment for NRAS-mutant melanoma are not very efficient and is currently limited to immune checkpoints inhibitors or aggressive chemotherapy. 4-nerolidylcathecol (4-NC), a natural product extracted from Pothomorphe umbellata, induces apoptosis in melanoma cells by ROS production, DNA damage and increased p53 expression, in addition to inhibiting invasion in reconstructed skin. Moreover, 4-NC showed cytotoxicity in BRAF/MEKi-resistant and naive melanoma cells by Endoplasmic Reticulum (ER) stress induction in vitro. We evaluated the in vivo efficacy and the systemic toxicity of 4-NC in a NRAS-mutant melanoma model. 4-NC was able to significantly suppress tumor growth 4-fold compared to controls. Cleaved PARP and p53 expression were increased indicating cell death. As a proof of concept, MMP-2 and MMP-14 gene expression were decreased, demonstrating a possible role of 4-NC in melanoma invasion inhibition. Toxicological analysis indicated minor changes in the liver and bone marrow, but this toxicity was very mild when compared to other proteasome inhibitors and ER stress inductors already described. Our data indicate that 4-NC can counteract melanoma growth in vivo with minor adverse effects, suggesting further investigation as a potential NRAS-mutant melanoma treatment.


Assuntos
Antineoplásicos/farmacologia , Catecóis/farmacologia , GTP Fosfo-Hidrolases/genética , Melanoma/patologia , Proteínas de Membrana/genética , Mutação , Neoplasias Cutâneas/patologia , Animais , Antineoplásicos/toxicidade , Catecóis/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Melanoma/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Cutâneas/genética , Testes de Toxicidade Subaguda , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Anticancer Agents Med Chem ; 20(9): 1038-1050, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32067622

RESUMO

BACKGROUND: Melanoma is the most aggressive skin cancer, and BRAF (V600E) is the most frequent mutation that led to the development of BRAF inhibitors (BRAFi). However, patients treated with BRAFi usually present recidivism after 6-9 months. Curcumin is a turmeric substance, and it has been deeply investigated due to its anti-inflammatory and antitumoral effects. Still, the low bioavailability and biodisponibility encouraged the investigation of different analogs. DM-1 is a curcumin analog and has shown an antitumoral impact in previous studies. METHODS: Evaluated DM-1 stability and cytotoxic effects for BRAFi-sensitive and resistant melanomas, as well as the role in the metalloproteinases modulation. RESULTS: DM-1 showed growth inhibitory potential for melanoma cells, demonstrated by reduction of colony formation, migration and endothelial tube formation, and cell cycle arrest. Subtoxic doses were able to downregulate important Metalloproteinases (MMPs) related to invasiveness, such as MMP-1, -2 and -9. Negative modulations of TIMP-2 and MMP-14 reduced MMP-2 and -9 activity; however, the reverse effect is seen when increased TIMP-2 and MMP-14 resulted in raised MMP-2. CONCLUSION: These findings provide essential details into the functional role of DM-1 in melanomas, encouraging further studies in the development of combinatorial treatments for melanomas.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Melanoma/tratamento farmacológico , Metaloproteases/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Melanoma/metabolismo , Melanoma/patologia , Metaloproteases/metabolismo , Estrutura Molecular , Proteínas Proto-Oncogênicas B-raf/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
5.
Anticancer Agents Med Chem, v. 20, n. 9, p. 1038-1050, jan. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3190

RESUMO

Background: Melanoma is the most aggressive skin cancer, and BRAF (V600E) is the most frequent mutation that led to the development of BRAF inhibitors (BRAFi). However, patients treated with BRAFi usually present recidivism after 6-9 months. Curcumin is a turmeric substance, and it has been deeply investigated due to its anti-inflammatory and antitumoral effects. Still, the low bioavailability and biodisponibility encouraged the investigation of different analogs. DM-1 is a curcumin analog and has shown an antitumoral impact in previous studies. Methods: Evaluated DM-1 stability and cytotoxic effects for BRAFi-sensitive and resistant melanomas, as well as the role in the metalloproteinases modulation. Results: DM-1 showed growth inhibitory potential for melanoma cells, demonstrated by reduction of colony formation, migration and endothelial tube formation, and cell cycle arrest. Subtoxic doses were able to downregulate important Metalloproteinases (MMPs) related to invasiveness, such as MMP-1, -2 and -9. Negative modulations of TIMP-2 and MMP-14 reduced MMP-2 and -9 activity; however, the reverse effect is seen when increased TIMP-2 and MMP-14 resulted in raised MMP-2. Conclusion: These findings provide essential details into the functional role of DM-1 in melanomas, encouraging further studies in the development of combinatorial treatments for melanomas.

6.
Pharmacol Res ; 141: 63-72, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30550954

RESUMO

Melanoma accounts for only 4% of malignant neoplasms of the skin, but is considered the most serious because it is highly deadly. Mutations in the MAPK (Ras-Raf-MEK-ERK) pathway is closely linked to the lack of control of cell proliferation. Especially in melanoma, this pathway has become a target for the development of oncogene-targeted therapies, such as the potent inhibitors of v-Raf murine sarcoma viral oncogene homolog B (BRAFi) and mitogen-activated protein kinase kinase (MEKi). Very high rates of response have been achieved, but most patients are relapsed due to the development of resistance, justifying the constant search for new therapeutic compounds. Early results from our group indicated that 4-nerolidylcatechol (4-NC), a catechol compound extracted from Pothomorphe umbellata, induces DNA damage, ROS production, increased p53 expression culminating in apoptosis in melanoma but with no data regarding the 4-NC effects in cells resistant to BRAFi or MEKi. Therefore, here we evaluated the role of 4-NC alone or in combination with BRAFi/MEKi in resistant melanoma cells. Double-resistant cells were generated and characterized by MAPK pathway reactivation. 4-NC alone or in combination (30 µM) with MAPK inhibitors was cytotoxic, inhibited colony formation and decreased invasiveness in two and three-dimensional cell culture models of treatment-naïve, BRAFi-resistant and BRAF/MEKi double-resistant melanoma cells. Apoptosis induction was demonstrated in resistant and double-resistant melanoma cell lines after 4-NC treatments. 4-NC showed important ability to induce apoptosis via Endoplasmatic Reticulum (ER) stress and specifically BiP and CHOP that had increased protein expression in all melanoma cell lines proving to be part of the ER stress pathway activation. CHOP knockdown slightly but enough increases cellular viability following 4-NC treatment indicating that apoptosis observed is partially dependent on CHOP. In summary, we show that 4-NC is a compound with activity against cutaneous melanoma, including resistant cells to clinically approved therapies.


Assuntos
Antineoplásicos/farmacologia , Catecóis/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico
7.
Pharmacol Res ; 125(Pt B): 178-187, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28882690

RESUMO

Melanoma is a highly invasive and metastatic cancer with high mortality rates and chemoresistance. Around 50% of melanomas are driven by activating mutations in BRAF that has led to the development of potent anti-BRAF inhibitors. However resistance to anti-BRAF therapy usually develops within a few months and consequently there is a need to identify alternative therapies that will bypass BRAF inhibitor resistance. The curcumin analogue DM-1 (sodium 4-[5-(4-hydroxy-3-methoxy-phenyl)-3-oxo-penta-1,4-dienyl]-2-methoxy-phenolate) has substantial anti-tumor activity in melanoma, but its mechanism of action remains unclear. Here we use a synthetic lethal genetic screen in Saccharomyces cerevisiae to identify 211 genes implicated in sensitivity to DM-1 toxicity. From these 211 genes, 74 had close human orthologues implicated in oxidative phosphorylation, insulin signaling and iron and RNA metabolism. Further analysis identified 7 target genes (ADK, ATP6V0B, PEMT, TOP1, ZFP36, ZFP36L1, ZFP36L2) with differential expression during melanoma progression implicated in regulation of tumor progression, cell differentiation, and epithelial-mesenchymal transition. Of these TOP1 and ADK were regulated by DM-1 in treatment-naïve and vemurafenib-resistant melanoma cells respectively. These data reveal that the anticancer effect of curcumin analogues is likely to be mediated via multiple targets and identify several genes that represent candidates for combinatorial targeting in melanoma.


Assuntos
Curcumina/análogos & derivados , Curcumina/farmacologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Melanoma/genética , Saccharomyces cerevisiae/genética , Linhagem Celular Tumoral , Biologia Computacional , Humanos , Mutação , Toxicogenética
8.
Pharmacol Res ; 111: 523-533, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27436149

RESUMO

The BRAF(V600E) mutation confers constitutive kinase activity and accounts for >90% of BRAF mutations in melanoma. This genetic alteration is a current therapeutic target; however, the antitumorigenic effects of the BRAF(V600E) inhibitor vemurafenib are short-lived and the majority of patients present tumor relapse in a short period after treatment. Characterization of vemurafenib resistance has been essential to the efficacy of next generation therapeutic strategies. Herein, we found that acute BRAF inhibition induced a decrease in active MMP-2, MT1-MMP and MMP-9, but did not modulate the metalloproteinase inhibitors TIMP-2 or RECK in naïve melanoma cells. In vemurafenib-resistant melanoma cells, we observed a lower growth rate and an increase in EGFR phosphorylation followed by the recovery of active MMP-2 expression, a mediator of cancer metastasis. Furthermore, we found a different profile of MMP inhibitor expression, characterized by TIMP-2 downregulation and RECK upregulation. In a 3D spheroid model, the invasion index of vemurafenib-resistant melanoma cells was more evident than in its non-resistant counterpart. We confirmed this pattern in a matrigel invasion assay and demonstrated that use of a matrix metalloproteinase inhibitor reduced the invasion of vemurafenib resistant melanoma cells but not drug naïve cells. Moreover, we did not observe a delimited group of cells invading the dermis in vemurafenib-resistant melanoma cells present in a reconstructed skin model. The same MMP-2 and RECK upregulation profile was found in this 3D skin model containing vemurafenib-resistant melanoma cells. Acute vemurafenib treatment induces the disorganization of collagen fibers and consequently, extracellular matrix remodeling, with this pattern observed even after the acquisition of resistance. Altogether, our data suggest that resistance to vemurafenib induces significant changes in the tumor microenvironment mainly by MMP-2 upregulation, with a corresponding increase in cell invasiveness.


Assuntos
Antineoplásicos/farmacologia , Indóis/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Melanoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Sulfonamidas/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/fisiologia , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Humanos , Interleucina-8/metabolismo , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Melanoma/genética , Melanoma/metabolismo , Invasividade Neoplásica , Proteínas Proto-Oncogênicas B-raf/genética , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Regulação para Cima , Vemurafenib
9.
Cancer Epidemiol Biomarkers Prev ; 24(10): 1539-47, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26261088

RESUMO

BACKGROUND: Matrix metalloproteinases (MMP) are important enzymes in the tumor microenvironment associated with progression of cervical intraepithelial neoplasia (CIN) toward squamous cell carcinoma (SCC) of the cervix. However, the role of MMPs in the inflammatory process associated with Chlamydia trachomatis infection concomitant with the carcinogenic process driven by HPV has not yet been addressed. In the present study, we analyzed the state of the MMP-9-RECK axis in cervical carcinogenesis. METHODS: The levels of MMP-9 and RECK expression were analyzed by immunocytochemistry in liquid-based cytology samples from 136 women with high-grade cervical lesions (CIN2/CIN3) and cervical SCC diagnosed by LLETZ, and in 196 women without cervical neoplasia or CIN1. Real-time qPCR was performed to analyze expression of MMP-9 and RECK in 15 cervical samples. The presence of HPV-DNA and other genital pathogens was evaluated by PCR. RESULTS: We found a higher expression of MMP-9 [OR, 4.2; 95% confidence interval (CI), 2.2-7.8] and lower expression of RECK (OR, 0.4; 95% CI, 0.2-0.7) in women with CIN2/CIN3/SCC when compared with women from the control group (no neoplasia/CIN1). A statistically significant association was also found between MMP-9/RECK imbalance and infection by alpha-9 HPV and C. trachomatis. The prevalence of C. trachomatis infection was significantly higher in women with high-grade cervical disease (OR, 3.7; 95% CI, 1.3-11.3). CONCLUSIONS: MMP-9/RECK imbalance in cervical smears is significantly associated with high-grade cervical diseases and infection by alpha-9 HPV and C. trachomatis. IMPACT: MMP-9/RECK imbalance during cervical inflammation induced by C. trachomatis might play a role in HPV-mediated cervical carcinogenesis.


Assuntos
Infecções por Chlamydia/genética , Proteínas Ligadas por GPI/genética , Regulação Neoplásica da Expressão Gênica , Metaloproteinase 9 da Matriz/genética , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/genética , Cervicite Uterina/genética , Adulto , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/virologia , Colo do Útero/metabolismo , Colo do Útero/patologia , Infecções por Chlamydia/metabolismo , Infecções por Chlamydia/patologia , Chlamydia trachomatis/genética , Estudos Transversais , DNA Bacteriano/genética , DNA de Neoplasias/genética , DNA Viral/genética , Feminino , Proteínas Ligadas por GPI/biossíntese , Regulação Bacteriana da Expressão Gênica , Genótipo , Papillomavirus Humano 16/genética , Humanos , Imuno-Histoquímica , Metaloproteinase 9 da Matriz/biossíntese , Teste de Papanicolaou , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/virologia , Cervicite Uterina/metabolismo , Cervicite Uterina/microbiologia , Esfregaço Vaginal
10.
Tissue Eng Part A ; 21(17-18): 2417-25, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26132636

RESUMO

The advanced glycation end products (AGEs) of proteins are common factors in the pathophysiology of a number of disorders related to aging. The skin generation of AGEs occurs mainly through nonenzymatic glycation reactions of extracellular matrix (ECM) proteins in the dermis. The AGEs have been touted as one of the factors responsible for healing impairment and loss of elasticity of healing skin, affecting growth, differentiation, and cellular motility, as well as cytokines response, metalloproteinases expression, and vascular hemostasis. In this study, we generated an in vitro full-thickness reconstructed skin based on a glycated collagen matrix dermal compartment to evaluate the effects of glycation on dermal ECM and ultimately on the epidermis. Epidermal differentiation and stratification patterns and the glycation-induced ECM changes were evaluated by histology, immunohistochemistry, and mRNA levels. In this study, we reported for the first time that changes in the dermal matrix caused by collagen I in vitro glycation processes also affect the epidermal compartment. We demonstrated that glycation of collagen induces expression of carboxymethyllysine in dermal and epidermal compartments and, consequently, an aging phenotype consisting of poor stratification of epidermal layers and vacuolization of keratinocyte cytoplasm. Increased expression of cell-cell adhesion markers, such as desmoglein and E-cadherin in glycated skins, is observed in the stratum spinosum, as well as an increased compression of dermal collagen matrix. We also submitted our 3D model of reconstructed glycated skin to screening of anti-AGE molecules, such as aminoguanidine, which prevented the glycated morphological status. Controlled human studies investigating the effects of anti-AGE strategies against skin aging are largely missing. In this context, we proposed the use of skin equivalents as an efficient model to investigate cellular interactions and ECM changes in the aging skin, and to elucidate the role of anti-AGEs molecules in this process.


Assuntos
Envelhecimento da Pele/patologia , Pele/patologia , Engenharia Tecidual , Animais , Diferenciação Celular , Epitélio/fisiologia , Matriz Extracelular/metabolismo , Glicosilação , Humanos , Masculino , Microscopia , Ratos , Pele/anatomia & histologia
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