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Cervical cancer is a health problem among women worldwide. Considering the limitations of prevention and antineoplastic chemotherapy against cervical cancer, research is needed to discover new, more effective, and safe antitumor agents. In the present study, we investigated the in vitro cytotoxicity of a new synthetic dibenzylideneacetone derived from 1,5-diaryl-3-oxo-1,4-pentadienyl (A3K2A3) against cervical cancer cells immortalized by HPV 16 (SiHa), and 18 (HeLa) by MTT assay. Furthermore, we performed spectrofluorimetry, flow cytometry, and Western blot analyzes to explore the inhibitory mechanism of A3K2A3 in cervical cancer cells. A3K2A3 showed cytotoxic activity against both cell lines. Mitochondrial depolarization and reduction in intracellular ATP levels were observed, which may be dependent on the redox imbalance between increased ROS and reduced levels of the antioxidant defense. In addition, damage to the cell membrane and DNA, and effective blocking of cell division in the G2/M phase were detected, which possibly led to the induction of apoptosis. This result was further confirmed by the upregulation of apoptosis-related proteins Bax, cytochrome C, and caspases 9 and 3. Our results provided the first evidence that A3K2A3 contributes to the suppression of cervical cancer in vitro, showing promise as a possible alternative for the treatment of this cancer.

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Abstract Curcumin, the primary polyphenol found in turmeric, is derived from the Curcuma longa plant. Since curcumin is nontoxic and has a wide range of medicinal qualities, including anti-oxidant, analgesic, anti-inflammatory, and antibacterial action, it has been widely employed in Ayurveda medicine for ages. Curcumin has recently been discovered to have anti-cancer properties through its impact on numerous biological pathways involved in carcinogenesis, metastasis, tumorigenesis, cell cycle regulation, mutagenesis, and oncogene expression. In this study, we determined the Antiproliferative activity and apoptosis-inducing mechanism of C. longa (Turmimax®) on human cancer cells. The cytotoxic effect was evaluated against HeLa cell lines using the MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. Flow cytometric analysis was performed to detect apoptotic cell death. Turmimax® exhibits promising properties as a potential anti-cancer therapeutic agent in human cervical adenocarcinomas and possibly other cancer types, with an IC50 value of 87.89 µg/mL. In HeLa cells treated with Turmimax®, cell cycle arrest was seen in the G0/G1 and S phases. By inducing apoptosis and increasing the number of apoptotic cells in a dose-dependent manner, the experimental data suggest that Turmimax® has considerable promise in cancer prevention and treatment.

Resumo A curcumina, o polifenol primário encontrado no açafrão, é derivada da planta Curcuma longa. Como a curcumina não é tóxica e possui ampla gama de qualidades medicinais, incluindo ação antioxidante, analgésica, anti-inflamatória e antibacteriana, ela tem sido muito empregada na medicina ayurvédica há séculos. Descobriu-se recentemente que a curcumina possui propriedades anticancerígenas por meio de seu impacto em várias vias biológicas envolvidas na carcinogênese, metástase, tumorigênese, regulação do ciclo celular, mutagênese e expressão de oncogenes. Neste estudo, determinamos a atividade antiproliferativa e o mecanismo de indução de apoptose de C. longa (Turmimax®) em células cancerígenas humanas. O efeito citotóxico foi avaliado em linhagens de células HeLa usando o ensaio MTT - brometo de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazólio. Uma análise de citometria de fluxo foi realizada para detectar a morte celular apoptótica. Turmimax® exibe propriedades promissoras como um potencial agente terapêutico anticancerígeno em adenocarcinomas cervicais humanos e possivelmente em outros tipos de câncer, com um valor de IC50 de 87,89 µg/mL. Nas células HeLa tratadas com Turmimax®, a parada do ciclo celular foi observada nas fases G0/G1 e S. Ao induzir a apoptose e aumentar o número de células apoptóticas de maneira dependente da dose, os dados experimentais sugerem que Turmimax® tem uma indicação considerável na prevenção e tratamento do câncer.

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The conventional treatment for toxoplasmosis with pyrimethamine and sulfadiazine shows toxic effects to the host, and it is therefore necessary to search for new drugs. Some studies suggest the use of statins, which inhibit cholesterol synthesis in humans and also the initial processes of isoprenoid biosynthesis in the parasite. Thus, the objective of this study was to evaluate the activity of the statins pravastatin and simvastatin in HeLa cells infected in vitro with the RH strain of T. gondii. HeLa cells (1×105) were infected with T. gondii tachyzoites (5×105) following two different treatment protocols. In the first protocol, T. gondii tachyzoites were pretreated with pravastatin (50 and 100µg/mL) and simvastatin (1.56 and 3.125µg/mL) for 30min prior to infection. In the second, HeLa cells were first infected (5×105) with tachyzoites and subsequently treated with pravastatin and simvastatin for 24h at the concentrations noted above. Initially, we evaluated the cytotoxicity of drugs by the MTT assay, number of tachyzoites adhered to cells, number of infected cells, and viability of tachyzoites by trypan blue exclusion. The supernatant of the cell cultures was collected post-treatment for determination of the pattern of Th1/Th2/Th17 cytokines by cytometric bead array. There was no cytotoxicity to HeLa cells with 50 and 100µg/mL pravastatin and 1.56 and 3.125µg/mL simvastatin. There was no change in the viability of tachyzoites that received pretreatment. Regarding the pre- and post-treatment of the cells with pravastatin and simvastatin alone, there was a reduction in adhesion, invasion and proliferation of cells to T. gondii. As for the production of cytokines, we found that IL-6 and IL-17 were significantly reduced in cells infected with T. gondii and treated with pravastatin and simvastatin, when compared to control. Based on these results, we can infer that pravastatin and simvastatin alone possess antiproliferative effects on tachyzoites forms of T. gondii, giving these drugs new therapeutic uses.

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A collection of 69 eae-positive strains expressing 29 different intimin types and eight tir alleles was characterizedwith respect to their adherence patterns to HeLa cells, ability to promote actin accumulation in vitro, the presence of bfpA alleles in positive strains, and bundle-forming pilus (BFP) expression. All of the nine typical enteropathogenic Escherichia coli (tEPEC) studied harbored the enteropathogenic E. coli adherence factor (EAF) plasmid, as shown by PCR and/or EAF probe results. In addition, they were positive for bfpA, as shown by PCR, and BFP expression, as confirmed by immunofluorescence(IFL) and/or immunoblotting (IBL) assays. Localized adherence (LA) was exclusively displayed by those ninetEPEC, while localized-adherence-like (LAL) was the most frequent pattern among atypical EPEC (aEPEC) and Shiga-toxinproducing E. coli (STEC). All LA and LAL strains were able to cause attaching and effacing (AE) lesions, as established by means of the FAS test. There was a significant association between the presence of tir allele á1 and bfpA-positive strains, and consequently, with the LA pattern. However, intimin type or bfpA was not associated with the adherence pattern displayed in HeLa cells. Among the eight bfpA alleles detected, a new type (â10; accession number FN391178) was identified in a strain of serotype O157:H45, and a truncated variant (â3.2-t; accession number FN 391181) in four strains belonging to differentpathotypes.

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