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1.
Front Oncol ; 11: 594917, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34354940

RESUMO

Pancreatic cancer is an aggressive, devastating disease due to its invasiveness, rapid progression, and resistance to surgical, pharmacological, chemotherapy, and radiotherapy treatments. The disease develops from PanINs lesions that progress through different stages. KRAS mutations are frequently observed in these lesions, accompanied by inactivation of PTEN, hyperactivation of the PI3K/AKT pathway, and chronic inflammation with overexpression of COX-2. Nimesulide is a selective COX-2 inhibitor that has shown anticancer effects in neoplastic pancreatic cells. This drug works by increasing the levels of PTEN expression and inhibiting proliferation and apoptosis. However, there is a need to improve nimesulide through its encapsulation by solid lipid nanoparticles to overcome problems related to the hepatotoxicity and bioavailability of the drug.

2.
Front Oncol ; 9: 541, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293975

RESUMO

Caffeic acid (CA) is a phenolic compound synthesized by all plant species and is present in foods such as coffee, wine, tea, and popular medicines such as propolis. This phenolic acid and its derivatives have antioxidant, anti-inflammatory and anticarcinogenic activity. In vitro and in vivo studies have demonstrated the anticarcinogenic activity of this compound against an important type of cancer, hepatocarcinoma (HCC), considered to be of high incidence, highly aggressive and causing considerable mortality across the world. The anticancer properties of CA are associated with its antioxidant and pro-oxidant capacity, attributed to its chemical structure that has free phenolic hydroxyls, the number and position of OH in the catechol group and the double bond in the carbonic chain. Pharmacokinetic studies indicate that this compound is hydrolyzed by the microflora of colonies and metabolized mainly in the intestinal mucosa through phase II enzymes, submitted to conjugation and methylation processes, forming sulphated, glucuronic and/or methylated conjugates by the action of sulfotransferases, UDP-glucotransferases, and o-methyltransferases, respectively. The transmembrane flux of CA in intestinal cells occurs through active transport mediated by monocarboxylic acid carriers. CA can act by preventing the production of ROS (reactive oxygen species), inducing DNA oxidation of cancer cells, as well as reducing tumor cell angiogenesis, blocking STATS (transcription factor and signal translation 3) and suppression of MMP2 and MMP-9 (collagen IV metalloproteases). Thus, this review provides an overview of the chemical and pharmacological parameters of CA and its derivatives, demonstrating its mechanism of action and pharmacokinetic aspects, as well as a critical analysis of its action in the fight against hepatocarcinoma.

3.
Transl Res ; 204: 51-71, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30304666

RESUMO

Aflatoxin B1 (AFB1) is currently the most commonly studied mycotoxin due to its great toxicity, its distribution in a wide variety of foods such as grains and cereals and its involvement in the development of + (hepatocellular carcinoma; HCC). HCC is one of the main types of liver cancer, and has become a serious public health problem, due to its high incidence mainly in Southeast Asia and Africa. Studies show that AFB1 acts in synergy with other risk factors such as hepatitis B and C virus leading to the development of HCC through genetic and epigenetic modifications. The genetic modifications begin in the liver through the biomorphic AFB1, the AFB1-exo-8.9-Epoxy active, which interacts with DNA to form adducts of AFB1-DNA. These adducts induce mutation in codon 249, mediated by a transversion of G-T in the p53 tumor suppressor gene, causing HCC. Thus, this review provides an overview of the evidence for AFB1-induced epigenetic alterations and the potential mechanisms involved in the development of HCC, focusing on a critical analysis of the importance of severe legislation in the detection of aflatoxins.


Assuntos
Aflatoxina B1/toxicidade , Carcinoma Hepatocelular/induzido quimicamente , Epigênese Genética/efeitos dos fármacos , Neoplasias Hepáticas/induzido quimicamente , Saúde Pública , Carcinoma Hepatocelular/genética , Metilação de DNA , Histonas/metabolismo , Humanos , Neoplasias Hepáticas/genética , MicroRNAs/fisiologia , Biossíntese de Proteínas , RNA Longo não Codificante/fisiologia , Risco
4.
Artigo em Inglês | MEDLINE | ID: mdl-27525023

RESUMO

The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS), were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing (1)H-NMR spectra and fifteen terpenes were identified by GC-MS. EEP-Y MS showed cytotoxic activity against human tumour strain OVCAR-8 but was not active against Gram-negative or Gram-positive bacteria. Our results confirm the difficulty of establishing a uniform quality standard for propolis from diverse geographical origins. The most appropriate pharmacological applications of yellow types of propolis must be further investigated.

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