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1.
Nutrients ; 13(9)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34578877

RESUMO

Background: Increasing evidence suggests that combinations of phytochemicals are more efficient than single components in the modulation of signaling pathways involved in cancer development. In this study, the impact of phenethyl isothiocyanate (PEITC), indole-3-carbinol (I3C), xanthohumol, (X), and resveratrol (RES) and their combinations on the activation and expression of Nrf2 and NF-κB in human hepatocytes and HCC cells were evaluated. Methods: THLE-2 and HepG2 cells were exposed to single phytochemicals and their combinations for 24 h. The activation of Nrf2 and NF-κB, expression of their target genes, and effect on cells survival were assessed. The tumor burden was evaluated in mice carrying xenografts. Results: All phytochemicals enhanced the activation and expression of Nrf2 and its target genes SOD and NQO1 in HepG2 cells. The increased expression of NQO1 (~90%) was associated with increased ROS generation. X + PEITC downregulated NF-κB activation reducing binding of its active subunits to DNA resulting in diminished COX-2 expression. In contrast to single phytochemicals, X + PEITC induced apoptosis. Moderate reduction of tumor burden in mice carrying xenografts following X and PEITC or their combination was observed. Conclusions: Since Nrf2 is overexpressed in HCC its reduced activation together with diminished level of NF-κB by X + PEITC may be considered as a strategy to support conventional HCC therapy.

2.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443375

RESUMO

The study aimed to evaluate the possible modulation of Nrf2, NF-ĸB and STAT3 signaling pathways in the colorectal cancer (CRC) cells line DLD-1 and HCT116 by secondary metabolites of lichens. An attempt was made to indicate the most promising targets in these signaling pathways. Attention was also paid to the effects of the compounds tested on CRC cells using anakoinosis-that is, simultaneous analysis of several signaling pathways. The effects of the tested natural compounds on the activity of selected transcriptional factors related to CRC were analyzed by Western blot and RT-PCR assays. The highest activity against CRC cells was shown by physodic and salazinic acids from the studied secondary metabolites of lichens. As a result, an increase in the activation of transcription factor Nrf2 and the expression of its selected target genes was observed. Physodic and salazinic acids induced the opposite effect in relation to the NF-κB and STAT3 pathways. These results confirmed our earlier observations that lichen-derived compounds have the ability to modulate signaling pathway networks. While caperatic acid affected Wnt/ß-catenin to the most extent, salazinic acid was the most potent modulator of Nrf2, NF-κB and STAT3 pathways. Physodic acid seemed to affect all the investigated pathways.


Assuntos
Neoplasias Colorretais/metabolismo , Depsídeos/farmacologia , Lactonas/farmacologia , Líquens/química , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Depsídeos/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lactonas/química , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Metabolismo Secundário/efeitos dos fármacos
3.
Molecules ; 26(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34443544

RESUMO

Naturally occurring pentacyclic triterpenoid oleanolic acid (OA) serves as a good scaffold for additional modifications to achieve synthetic derivatives. Therefore, a large number of triterpenoids have been synthetically modified in order to increase their bioactivity and their protective or therapeutic effects. Moreover, attempts were performed to conjugate synthetic triterpenoids with non-steroidal anti-inflammatory drugs (NSAIDs) or other functional groups. Among hundreds of synthesized triterpenoids, still the most promising is 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO), which reached clinical trials level of investigations. The new group of synthetic triterpenoids are OA oximes. The most active among them is 3-hydroxyiminoolean-12-en-28-oic acid morpholide, which additionally improves the anti-cancer activity of standard NSAIDs. While targeting the Nrf2 and NF-κB signaling pathways is the main mechanism of synthetic OA derivatives' anti-inflammatory and anti-cancer activity, most of these compounds exhibit multifunctional activity, and affect cross-talk within the cellular signaling network. This short review updates the earlier data and describes the new OA derivatives and their conjugates in the context of modification of signaling pathways involved in inflammation and cell survival and subsequently in cancer development.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Ácido Oleanólico/farmacologia , Animais , Humanos , Simulação de Acoplamento Molecular , Ácido Oleanólico/química , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
4.
Pharmaceuticals (Basel) ; 14(7)2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34358114

RESUMO

Combining NSAIDs with conventional therapeutics was recently explored as a new strategy in cancer therapy. Our earlier studies showed that novel oleanolic acid oximes (OAO) conjugated with aspirin or indomethacin may enhance their anti-cancer potential through modulation of the Nrf2 and NF-κB signaling pathways. This study focused on the synthesis and biological evaluation of four diclofenac (DCL)-OAO derivative conjugates in the context of these pathways' modification and hepatic cells survival. Treatment with the conjugates 4d, 3-diclofenacoxyiminoolean-12-en-28-oic acid morpholide, and 4c, 3-diclofenacoxyiminoolean-12-en-28-oic acid benzyl ester significantly reduced cell viability in comparison to the DCL alone. In THLE-2, immortalized normal hepatocytes treated with these conjugates resulted in the activation of Nrf2 and increased expression in SOD-1 and NQO1, while the opposite effect was observed in the HepG2 hepatoma cells. In both cell lines, reduced activation of the NF-κB and COX-2 expression was observed. In HepG2 cells, conjugates increased ROS production resulting from a reduced antioxidant defense, induced apoptosis, and inhibited cell proliferation. In addition, the OAO morpholide derivative and its DCL hybrid reduced the tumor volume in mice bearing xenografts. In conclusion, our study demonstrated that conjugating diclofenac with the OAO morpholide and a benzyl ester might enhance its anti-cancer activity in HCC.

5.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360990

RESUMO

Nrf2 (nuclear factor erythroid 2-related factor 2) and NF-κB (nuclear factor-kappa B) signaling pathways play a central role in suppressing or inducing inflammation and angiogenesis processes. Therefore, they are involved in many steps of carcinogenesis through cooperation with multiple signaling molecules and pathways. Targeting both transcription factors simultaneously may be considered an equally important strategy for cancer chemoprevention and therapy. Several hundreds of phytochemicals, mainly edible plant and vegetable components, were shown to activate Nrf2 and mediate antioxidant response. A similar number of phytochemicals was revealed to affect NF-κB. While activation of Nrf2 and inhibition of NF-κB may protect normal cells against cancer initiation and promotion, enhanced expression and activation in cancer cells may lead to resistance to conventional chemo- or radiotherapy. Most phytochemicals, through different mechanisms, activate Nrf2, but others, such as luteolin, can act as inhibitors of both Nrf2 and NF-κB. Despite many experimental data confirming the above mechanisms currently, limited evidence exists demonstrating such activity in humans. Combinations of phytochemicals resembling that in a natural food matrix but allowing higher concentrations may improve their modulating effect on Nrf2 and NF-κB and ultimately cancer prevention and therapy. This review presents the current knowledge on the effect of selected phytochemicals and their combinations on Nrf2 and NF-κB activities in the above context.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Neoplasias/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Humanos , Neoplasias/metabolismo , Neoplasias/prevenção & controle , Transdução de Sinais/efeitos dos fármacos
6.
Nutr Cancer ; : 1-16, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34120541

RESUMO

Cancer prevention particularly related to aging can be improved by the use of phytochemicals combinations. In this study, we evaluated the effect of phenethyl isothiocyanate (PEITC), xanthohumol (XAN), indole-3-carbinol (I3C), and resveratrol (RES) and their combinations on the Nrf2 signaling pathway. Human pancreatic cancer cells MIA-Pa-Ca-2 were treated with the phytochemicals alone or their equimolar mixture for 24 h and activation of Nrf2 and expression of its target genes were evaluated. Phytochemicals alone enhanced Nrf2 activation and expression, but their combinations were more efficient. The mixture of XAN and PEITC was found to be the most potent modulator of the Nrf2 pathway. Moreover, increased levels of P-Nrf2 and P-JNK and decreased level of P-GSK-3ß suggested possible activation of Nrf2 through modulation of these kinases. The combinations of XAN with PEITC and RES with PEITC increased mostly the expression of SOD, GSTP, CAT, and GPx. XAN and PEITC mixture induced the cell cycle arrest in G0/G1 phase and increased apoptotic and autophagy markers. These results indicate that combinations of phytochemicals resembling that occurring in natural diets may efficiently modulate the signaling pathways, which proper function is important for pancreatic cancer prophylaxis or improving the results of conventional therapy.

7.
Mol Cell Biochem ; 476(6): 2539-2549, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33635505

RESUMO

Naturally occurring phytochemicals of different origin and structure, arctigenin, bergenin, usnic acid and xanthohumol, were shown to affect Nrf2 pathway in the context of various diseases, but their effect on this pathway in cancer cells was not extensively investigated. This study aimed to evaluate the effect of these compounds on Nrf2 expression and activation in hypopharyngeal FaDu squamous cell carcinoma cells. FaDu cells were treated with 2 or 10 µM arctigenin, bergenin, (+)-usnic acid or xanthohumol for 24 h. While arctigenin, bergenin, and xanthohumol did not affect either Nrf2 expression or activation, (+)-usnic acid treatment increased its transcript level and increased the nuclear/cytosol Nrf2 protein ratio-the measure of Nrf2 pathway activation. Consequently, (+)-usnic acid enhanced the transcription and translation of Nrf2 target genes: NQO1, SOD, and to a lesser extent, GSTP. The treatment of FaDu cells with (+)-usnic acid decreased both GSK-3ß transcript and protein level, indicating its possible involvement in Nrf2 activation. All the tested compounds decreased Bax mRNA but did not change the level of Bax protein. (+)-Usnic acid tended to increase the percentage of early apoptotic cells and LC3 protein, autophagy marker. Significant induction of p53 also was observed after treatment with (+)-usnic acid. In summary, the results of this study indicate that low concentrations of (+)-usnic acid activate Nrf2 transcription factor, most probably as a result of ROS accumulation, but do not lead to FaDu hypopharyngeal carcinoma cells death.


Assuntos
Elementos de Resposta Antioxidante , Benzofuranos/farmacologia , Neoplasias Hipofaríngeas/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Neoplasias Hipofaríngeas/tratamento farmacológico , Neoplasias Hipofaríngeas/genética , Neoplasias Hipofaríngeas/patologia , Fator 2 Relacionado a NF-E2/genética , Proteínas de Neoplasias/genética , Transdução de Sinais/genética
9.
Mol Cell Biochem ; 474(1-2): 113-123, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32737773

RESUMO

The present study aimed to evaluate the cytotoxicity and its mechanism of five synthetic methoxy stilbenes, namely 3,4,4'-trimethoxy, 3,4,2'-trimethoxy, 3,4,2',4'-tetramethoxy, 3,4,2',6'-tetramethoxy, and 3,4,2',4',6'-pentamethoxy-trans-stilbenes (MS), in comparison with resveratrol (RSV). Human promyelocytic (HL-60) and monocytic leukemia (THP-1) cells were treated with the tested compounds for 24 h, and cytotoxicity, cell cycle distribution, and apoptosis were evaluated. Significant differences were found in the susceptibility of these cell lines to all stilbenes, including RSV. The THP-1 cells were more resistant to cytotoxic activity of these compounds than HL-60 cells. Among the tested stilbenes, 3,4,4'-tri-MS and 3,4,2',4'-tetra-MS exhibited higher cytotoxicity toward both cell lines than RSV and the other methoxy stilbenes. This activity might be related to cell cycle arrest at the G2/M phase and induction of apoptosis. In this regard, 3,4,4'-tri-MS and 3,4,2',4'-tetra-MS at highest concentrations increased the p53 protein level particularly in HL-60 cells. Moreover, treatment with these derivatives increased the ratio of the proapoptotic Bax protein to the antiapoptotic Bcl-xl protein, suggesting the induction of apoptosis through the intrinsic mitochondrial pathway in both cell lines. Further studies are required to fully elucidate the mechanism of these activities.


Assuntos
Apoptose , Pontos de Checagem do Ciclo Celular , Leucemia Mieloide/tratamento farmacológico , Resveratrol/análogos & derivados , Resveratrol/farmacologia , Estilbenos/química , Antioxidantes/farmacologia , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Células HL-60 , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/metabolismo
10.
Eur J Pharmacol ; 883: 173307, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32668287

RESUMO

Our previous study demonstrated that new oleanolic acid oxime (OAO) derivatives and their conjugates with aspirin (ASP) inhibit NF-κB activation. Evidence exists that the downregulation of NF-κB negatively interferes with the Nrf2 signaling pathway. This study aimed to evaluate the effect of these compounds on Nrf2 activation and its cellular consequences in human hepatoma HepG2 cells and immortalized normal hepatocytes THLE-2. The results showed the enhanced activation and expression of Nrf2 as a result of treatment with OAO derivatives themselves and to less extent by their ASP conjugates, mainly in HepG2 cells. The association between cytotoxicity evaluated in our previous study and Nrf2 activation was observed. In this regard, compounds (18) with morpholide substituent at the C-17 position of OAO molecule and (12) with methyl ester substituent at the same position of OAO molecule to the most extent activated Nrf2 and subsequently cell cycle arrest at G2/M, leading to increased apoptosis and the number of resting HepG2 cells. The derivative of OAO (18) substituted with ASP (19) also affected Nrf2 activation and expression, but this effect was less pronounced in comparison with non-conjugated OAO. However, conjugation enhanced Nrf2 activation in normal THLE-2 cells. These results confirmed our earlier suggestion that OAO derivatives conjugated with ASP have the potential for application in the liver cancer chemoprevention. OAO themselves, particularly OAO substituted with morpholide, may be considered therapeutic agents, which may support conventional treatment strategy. Further studies are required to confirm this suggestion.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
11.
Toxicol In Vitro ; 65: 104799, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32070777

RESUMO

Phytochemicals such as phenethyl isothiocyanate (PEITC), indole-3-carbinol (I3C), xanthohumol (XAN), and resveratrol (RES) have been shown to target signaling pathways that are involved in the proliferation and survival of different pancreatic cancer (PC) cell lines. While the activity of these compounds alone was extensively studied, their combinations were never assessed. Thus, the aim of this study was to evaluate and compare the effect of PEITC, I3C, XAN, and RES and their combinations on the expression and activation of NF-κB and Nrf2 in human PC cell line PANC-1. The combination of XAN and PEITC was more efficient than the single compounds in reducing the binding of NF-κB p65 subunits to DNA by 47-60% and expression of p65 gene by 28-48%. The combination of XAN and PEITC also enhanced the activation and expression of Nrf2 and subsequently the expression of GSTP, NQO1, and SOD genes which are controlled by this transcription factor. Modulation of the activity of NF-κB and Nrf2 by the combination of XAN and PEITC was found to lead to reduced proliferation of PANC-1 cells. These results suggest that the combination of XAN and PEITC might be considered as a novel strategy for the prophylaxis and/or treatment of PC.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Flavonoides/farmacologia , Isotiocianatos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/antagonistas & inibidores , Neoplasias Pancreáticas/metabolismo , Propiofenonas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Indóis/farmacologia , NF-kappa B/metabolismo , Resveratrol/farmacologia
12.
Pharmaceuticals (Basel) ; 14(1)2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33396453

RESUMO

Nrf2 and NF-κB play a key role in inflammation-driven cancers. Conjugation of anti-inflammatory drugs with oleanolic acid oxime (OAO) may enhance their therapeutic potential as a result of downregulation of these pathways. Novel OAO derivatives conjugated with indomethacin (IND) were synthesized, and their effect on the activation and expression of Nrf2 and NF-κB in HepG2 hepatoma cells and THLE-2 immortalized normal hepatocytes was evaluated in relation to cell cycle arrest and apoptosis. Treatment with OAO-IND conjugates reduced the activation of Nrf2 and NF-κB and the expression of their active forms in HepG2 cells, while in normal hepatocytes, the activation of Nrf2 was increased and NF-κB diminished. Compounds 3d, 3-indomethacinoxyiminoolean-12-en-28-oic acid morpholide, and 3c, 3-indomethacinoxyiminoolean-12-en-28-oic acid benzyl ester, were the most efficient. In THLE-2 cells, as opposed to HepG2 cells, the expressions of SOD-1 and NQO1 were significantly enhanced after treatment with these compounds. The COX-2 expression was diminished in both cell lines. OAO-IND derivatives affected the cell cycle arrest at G2/M, leading to increased apoptosis and increased number of resting HepG2 cells. Therefore, the conjugation of IND with OAO derivatives may preserve cancer cells against chemoresistance through the inhibition of the Nrf2-ARE pathway and NF-κB and, at the same time, exert a chemopreventive effect in normal hepatocytes.

13.
Bioorg Chem ; 93: 103326, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31586705

RESUMO

The aim of this study was to evaluate the effect of new oleanolic acid oxime (OAO) derivatives and their conjugates with aspirin (ASP) on the expression and activation of NF-κB in human hepatoma HepG2 cells. OAO derivatives showed a stronger cytotoxic effect against HepG2 cells compared with their conjugates with aspirin. Moreover, conjugation of OAO with ASP led to enhanced downregulation of NF-κB expression and activation. Among the hybrids with ASP, compounds: 19, 3-(2-acetoxy)benzoyloxyiminoolean-12-en-28-oic acid morpholide and 13, 3-(2-acetoxy)benzoyloxyiminoolean-12-en-28-oic acid methyl ester, differing, respectively, in morpholide and methyl ester groups at the C-17 position of oleanolic acid (OA) molecule were the most efficient. COX-2 transcript and protein levels were also diminished after treatment with these compounds. The results of this study indicate that the new derivatives of OAO and particularly their conjugates with ASP, downregulate the expression of COX-2 in HepG2 cells by modulating the NF-κB signaling pathway and suggest their potential application in the prevention of liver inflammation and cancer.


Assuntos
Aspirina/química , NF-kappa B/metabolismo , Ácido Oleanólico/farmacologia , Oximas/química , Transcrição Genética/efeitos dos fármacos , Células Hep G2 , Humanos , Ácido Oleanólico/química , Transdução de Sinais/efeitos dos fármacos
14.
Pharmacol Rep ; 71(6): 1001-1005, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31561186

RESUMO

BACKGROUND: "Orphan" cytochromes are a new group of P450 cytochromes without a fully recognized biological role. The expression of these CYPs in tumors is higher than that in normal tissues, which makes them attractive as chemopreventive and/or therapeutic targets. In this study, we compared the effect of synthetic methoxy stilbenes and resveratrol on the expression of two orphan cytochromes, CYP2S1 and CYP2W1, in breast cancer cells. METHODS: Breast cancer cells, lines MCF7 and MDA-MB-231, were treated for 72 h with tested compounds. The expression of CYP2S1 and CYP2W1 was evaluated at the transcript and protein levels by RT-PCR and Western blot, respectively. RESULTS: The constitutive expression of both isoforms was confirmed at the mRNA and protein levels. CYP2S1 and CYP2W1 showed higher expression in MDA-MB-231 cells. In MCF7 cells treated with stilbenes, the expression of both CYPs was increased at the mRNA level, whereas at the protein level this effect was confirmed for CYP2S1 alone. In contrast, in estrogen receptor-negative MDA-MB-231 cells treated with stilbenes, the expression of both CYPs decreased, but mostly at the transcript level. CONCLUSIONS: The results of the present study confirmed the constitutive expression of CYP2S1 and CYP2W1 in breast cancer cells, although their relatively low level of expression suggests that they may be less involved in the transformation of therapeutic agents in these types of tumors. Stilbenes, particularly 3MS and 4MS, can modulate the expression of "orphan" CYPs more efficiently than resveratrol.


Assuntos
Neoplasias da Mama/enzimologia , Sistema Enzimático do Citocromo P-450/biossíntese , Família 2 do Citocromo P450/biossíntese , Estilbenos/farmacologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Indução Enzimática/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/enzimologia , Células Epiteliais/patologia , Feminino , Humanos , Células MCF-7 , Resveratrol/farmacologia
15.
Chem Biol Interact ; 311: 108786, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31401087

RESUMO

Naturally occurring oleanolic acid (OA) possesses a hepatoprotective activity and ability to inhibit proliferation of human hepatocellular carcinoma cells. Both properties might be related to its anti-inflammatory activity. Its low bioavailability justifies the search for more hydrophilic OA derivatives. The aim of this study was the design and synthesis of four novel OA oxime derivatives conjugated with succinic acid at the C-3 position of oleanane skeleton structure and evaluation of their effect on NF-κB and STATs expression and activation in HepG2 cells. The expression of NF-κB and cyclooxygenase-2 (COX-2), STAT5A/B and STAT3 with its target genes: BAX, BCL-XL and MYC was evaluated after 24 h treatment with tested compounds. The comparison of the levels of cytosolic and nuclear NF-κB subunits p50, p65 and STATs proteins was used as the measure of their activation. The results pointed out the 3-succinyloxyiminoolean-12-en-28-oic acid morpholide (SMAM) as the most potent modulator of NF-κB and STAT3. SMAM significantly reduced the expression and activation of NF-κB as well as its nuclear protein level of p65 subunit. This compound also reduced the expression and activation of STAT3 and STAT5A/B. Combined effect of SMAM on these transcription factors resulted in reduced expression of COX-2, MYC and anti-apoptotic BCL-XL genes. Simultaneously, the increased expression of pro-apoptotic BAX gene was observed. In the cells treated with 3-succinyloxyiminoolean-12-en-28-oic acid (SMAA) the increased expression of BAX was also found. The effects of 3-succinyloxyiminoolean-12-en-28-oic acid benzyl ester (SMAEB) and 3-succinyloxyiminoolean-12-en-28-oic acid methyl ester (SMAEM) were moderate and ambiguous in relation to the tested factors. Moreover, the coordinated action of SMAM on NF-κB and STAT3 confirms their close association in HepG2 cells. We conclude that SMAM efficiently downregulates the key elements of signaling pathways involved in inflammatory driven HCC. Thus, may be considered as a potential chemopreventive or therapeutic agent in this type of cancer.


Assuntos
NF-kappa B/metabolismo , Ácido Oleanólico/análogos & derivados , Oximas/farmacologia , Fatores de Transcrição STAT/metabolismo , Ácido Succínico/química , Carcinoma Hepatocelular , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas , NF-kappa B/genética , Oximas/química , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição STAT/genética , Transcrição Genética/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
16.
Cell Oncol (Dordr) ; 42(4): 505-520, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31089983

RESUMO

PURPOSE: Activation of the Wnt pathway contributes to the development of head and neck squamous cell carcinomas (HNSCC) and its inhibition has recently emerged as a promising therapeutic strategy. Here, we aimed at identifying suitable molecular targets for down-regulation of canonical Wnt signaling in HNSCC cells. METHODS: Candidate target genes (PORCN, WNT3A, FZD2, FZD5, LRP5, DVL1, CIP2A, SET, KDM1A, KDM4C, KDM6A, CBP, CARM1, KMT2A, TCF7, LEF1, PYGO1, XIAP) were silenced using siRNA and selected targets were subsequently blocked using small molecule inhibitors. The effect of this treatment on the expression of ß-catenin-dependent genes was assessed by qRT-PCR. The effect of the inhibitors on cell viability was evaluated using a resazurin assay in HNSCC-derived cell lines. A luciferase reporter assay was used for confirmation of the inhibition of Wnt-dependent gene expression. Cell migration was evaluated using a scratch wound healing assay. Cytometric analysis of propidium iodide stained cells was used for cell cycle distribution evaluation, whereas cytometric analysis of caspase 3/7 activity was used for apoptosis induction evaluation. RESULTS: We found that inhibition of Porcupine and CBP/ß-catenin interaction by IWP-2 and PRI-724, respectively, most strongly affected ß-catenin-dependent gene expression in HNSCC cells. These inhibitors also induced apoptosis and affected HNSCC cell migration. CONCLUSIONS: Targeting Porcupine or the CBP/ß-catenin interaction seems to be an effective strategy for the inhibition of canonical Wnt signaling in HNSCC cells. Further studies are required to confirm the possible therapeutic effect of IWP-2 and PRI-724 in HNSCC.


Assuntos
Aciltransferases/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/patologia , Proteínas de Membrana/metabolismo , Fragmentos de Peptídeos/metabolismo , Sialoglicoproteínas/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Neoplasias de Cabeça e Pescoço/genética , Humanos , Bibliotecas de Moléculas Pequenas/farmacologia , Survivina/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos
17.
Cytotechnology ; 70(5): 1349-1362, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29808373

RESUMO

The aim of this study was to evaluate the cytotoxicity of a series of seven 4'-methylthio-trans-stilbene derivatives against cancer cells: MCF7 and A431 in comparison with non-tumorigenic MCF12A and HaCaT cells. The mechanism of anti-proliferative activity of the most cytotoxic trans-resveratrol analogs: 3,4,5-trimethoxy-4'-methylthio-trans-stilbene (3,4,5-MTS) and 2,4,5-trimethoxy-4'-methylthio-trans-stilbene (2,4,5-MTS) was analyzed and compared with the effect of trans-resveratrol. All the compounds that were studied exerted a stronger cytotoxic effect than trans-resveratrol did. MCF7 cells were the most sensitive to the cytotoxic effect of trans-resveratrol analogs with IC50 in the range of 2.1-6.0 µM. Comparing the cytotoxicity of 3,4,5-MTS and 2,4,5-MTS, a significantly higher cytotoxic activity of these compounds against MCF7 versus MCF12A was observed, whereas no significant difference was observed in cytotoxicity against A431 and HaCaT. In the series of 4'-methylthio-trans-stilbenes, 3,4,5-MTS and 2,4,5-MTS were the most promising compounds for further mechanistic studies. The proapoptotic activity of 3,4,5-MTS and 2,4,5-MTS, estimated with the use of annexin-V/propidium iodide assay, was comparable to that of trans-resveratrol. An analysis of cell cycle distribution showed a significant increase in the percentage of apoptotic cells and G2/M phase arrest in MCF7 and A431 as a result of treatment with 3,4,5-MTS, whereas trans-resveratrol tended to increase the percentage of cells in S phase, particularly in epithelial breast cells MCF12A and MCF7. Both trans-stilbene derivatives enhanced potently tubulin polymerization in a dose-dependent manner with sulfur atom participating in the interactions with critical residues of the paclitaxel binding site of ß-tubulin.

18.
Adv Clin Exp Med ; 27(6): 735-742, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29790697

RESUMO

BACKGROUND: Cancer cells are dependent on aerobic glycolysis for energy production and increased glutamine consumption. HIF-1α and c-MYC transcription factors regulate the expression of glycolytic and glutaminolytic genes. Their activity may be repressed by SIRT6. Head and neck carcinomas show frequent activation of c-MYC function and SIRT6 down-regulation, which contributes to a strong dependence on glucose and glutamine availability. OBJECTIVES: The aim of this study was to compare the influence of HIF-1α and c-MYC inhibitors (KG-548 and 10058-F4, respectively) and potential SIRT6 inducers - resveratrol and its synthetic derivative DMU-212 with the effect of glycolysis and glutaminolysis inhibitors (2-deoxyglucose and aminooxyacetic acid, respectively) on the metabolism and expression of metabolic enzymes in FaDu hypopharyngeal carcinoma cells. MATERIAL AND METHODS: Cell viability was assessed by means of an MTT assay. Quantitative PCR was performed to evaluate the expression of SIRT6, HIF-1α, c-MYC, GLUT1, SLC1A5, HK2, PFKM, PKM2, LDHA, GLS, and GDH. The release of glycolysis and glutaminolysis end-products into the culture medium - lactate and ammonia, respectively - was assessed using standard colorimetric assays. RESULTS: Lactate production was significantly inhibited by 10058-F4, KG-548, and 2-deoxyglucose. Moreover, 10058-F4 strongly reduced the amount of ammonia release. The effects of 10058-F4 activity can be attributed to a reduction in the expression of PKM2 and LDHA. On the other hand, the induction of SIRT6 expression by resveratrol and DMU-212 was not associated with significant modulation of the expression of metabolic enzymes. CONCLUSIONS: Overall, the results of this study indicate that the inhibition of c-MYC may be considered to be a promising strategy of the modulation of cancer-related metabolic changes in head and neck carcinomas.


Assuntos
Glutamina/metabolismo , Glicólise/fisiologia , Neoplasias Hipofaríngeas/metabolismo , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Neoplasias Hipofaríngeas/patologia , Tiazóis/farmacologia
19.
Mol Cell Biochem ; 444(1-2): 53-62, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29189985

RESUMO

Our previous study showed that the new synthetic methoxy-stilbenes, 3,4,2'-trimethoxy-trans-stilbene (3MS), 3,4,2',4'-tetramethoxy-trans-stilbene (4MS), and 3,4,2',4',6'-pentamethoxy-trans-stilbene (5MS), modulate the constitutive expression of enzymes and receptors involved in estrogen metabolism in breast immortalized epithelial MCF10 cells. In this study, we evaluated the effect of 3MS, 4MS, and 5MS in comparison to resveratrol activity in MCF7 estrogen-dependent and MDA-MB-231 estrogen-independent breast cancer cell lines. 3MS similarly to resveratrol reduced the expression of estrogen receptor α in MCF7 cells. However, in these cells, 5MS reduced the most CYP19, the gene encoding aromatase, at mRNA transcript level. In contrast, in the MDA-MB-231 cells, the most efficient inhibitor of CYP19 expression was 3MS, reducing the level of its protein by ~ 25%. This stilbene also inhibited the aromatase activity in a recombinant protein system with IC50 value ~ 85 µM. Treatment with the methoxy-stilbenes reduced the level of estradiol in culture medium. The most significant reduction was exerted by 3MS. None of the tested stilbenes including resveratrol changed significantly the expression of AhR, although CYP1A1 protein level was slightly reduced in MDA-MB-231 cells, while CYP1B1 expression was increased in these cells as a result of treatment with 3MS, but only at the transcript level. Overall, these results show weak or moderate effect of the new methoxy-stilbenes on the expression of key proteins involved in estrogens metabolism in cancer breast cells. However, the reduced CYP19 expression and activity upon 3MS treatment in metastatic MDA-MB-231 cells require the further studies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Neoplasias da Mama/metabolismo , Sistema Enzimático do Citocromo P-450/biossíntese , Receptor alfa de Estrogênio/biossíntese , Estrogênios/biossíntese , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Neoplasias/biossíntese , Receptores de Hidrocarboneto Arílico/biossíntese , Estilbenos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Estilbenos/química
20.
Reprod Sci ; 24(11): 1520-1531, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29017438

RESUMO

Hypertensive Disorders of Pregnancy (HDsP) remain leading causes of maternal and perinatal morbidity and mortality. Growing evidence suggests the involvement of epigenetic factors, such as gene-specific and global DNA methylation changes, both in the etiology and as an effect of HDsP. In this study, we investigated the potential association between placental DNA methylation status in selected CpGs of HSD11B2 cortisol level controlling gene, RUNX3 tumor suppressor gene, and long interspersed nucleotide element-1 (LINE-1) repetitive elements and HDsP-preeclampsia (PE), gestational hypertension (GH), and chronic hypertension (CH). Methylation-specific polymerase chain reaction (MSP) and pyrosequencing (PSQ) were used to analyze placental DNA methylation. Plasma and urine cortisol and cortisone levels were measured using high performance liquid chromatography with fluorescence detection (HPLC-FLD), whereas serum progesterone level was determined by electrochemiluminescence immunoassay. The mean percentage of HSD11B2, RUNX3, and LINE-1 methylation was not altered in the placentas of patients with HDsP, as compared to the controls. However, among patients from PE, GH, and CH groups, several significant correlations were observed between the methylation status of HSD11B2, RUNX3, or LINE-1 and children's birth weight, gestational age at delivery, mother's age, and body mass index as well as hormones levels. These results indicate lack of association between methylation status of HSD11B2, RUNX3, or LINE-1 repetitive elements and HDsP. However, association of these parameters with some clinical variables may suggest the role of placental DNA methylation in fetal development and should be further explored.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Metilação de DNA/fisiologia , Hipertensão/metabolismo , Placenta/metabolismo , Proteínas/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Feminino , Humanos , Hipertensão/patologia , Hipertensão Induzida pela Gravidez/metabolismo , Hipertensão Induzida pela Gravidez/patologia , Placenta/patologia , Gravidez , Adulto Jovem
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