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β-Lapachone is a natural naphthoquinone originally obtained from the bark of the purple Ipe (Tabebuia avellanedae Lor, Bignoniaceae) and its therapeutic potential in human cancer cells has been evaluated in several studies. In this study, we examined the effects of β-lapachone and its 3-iodine derivatives (3-I-α-lapachone and 3-I-β-lapachone) on cell proliferation, cell death, and cancer-related gene expression in human oral squamous cell carcinoma cells. β-Lapachone and its 3-iodine derivatives showed potent cytotoxicity against different types of human cancer cell lines. Indeed, treatment with these compounds induced cell cycle arrest at G2/M phase, followed by internucleosomal DNA fragmentation, and caused significant increases in phosphatidylserine externalization, caspase-8 and -9 activation, mitochondrial membrane depolarization, reactive oxygen species (ROS) production, and apoptotic cell death morphology. The apoptosis induced by the compounds was prevented by pretreatment with a pan-caspase inhibitor (Z-VAD-FMK) and an antioxidant (N-acetyl- l -cysteine). In vivo, β-lapachone and its 3-iodine derivatives significantly reduced tumor burden and did not alter any of the biochemical, hematological, or histological parameters of the animals. Overall, β-lapachone and its 3-iodine derivatives showed promising cytotoxic activity due to their ability to induce cell cycle arrest at G2/M phase and promote caspase- and ROS-mediated apoptosis. In addition, β-lapachone and its 3-iodine derivatives were able to suppress tumor growth in vivo, indicating that these compounds may be new antitumor drug candidates.

The present study aims to assess the influence of Aluminum-Gallium-Indium-Phosphide laser (AlGaInP laser, λ = 660 nm), whether or not in association with the application of a membrane of bacterial cellulose (Nexfill™), during recovery from induced second-degree burns at the dorsum of Wistar rats. (Rattus norvegicus, Wistar). Forty-eight animals have been distributed into four groups: Control (burns remained untreated), Group I (laser-treated), Group II (treated with Nexfill), and Group III (laser + Nexfill™). In addition to a morphological analysis, immunohistochemical analysis has been performed for type I collagen, type III collagen, fibronectin, and laminin. The Fisher's Test was used to assess differences among groups (p 0,05). A larger amount of collagen type III was observed in Control, Group II and Group III when compared with Group I (p 0,05). Group I and Group III have shown a greater collagen deposition when compared with Group II (p 0,05), but the amount of collagen was similar in Group I, Group III, and Control. Group III has shown larger fibronectin amounts in comparison with Group II (p 0,05). As regards laminin, Group I has shown a predominant discontinuity pattern on the basal lamina in comparison with Control, Group II, and Group III (p 0,05). It is concluded that in this current study the laser when used alone (Group I) hasn't influenced collagen deposition neither has it acted on fiber pattern (fibril and/or reticular). Moreover, laser application hasn't accelerated the repair of wounds caused by inflicted second-degree burns.

Submitted by Renorbio (renorbioba@ufba.br) on 2018-05-02T18:48:24Z No. of bitstreams: 1 ANTI-LIVER CANCER ACTIVITY IN VITRO AND IN VIVO INDUCED BY 2-PYRIDYL 2,3-THIAZOLE DERIVATIVES.pdf: 2793458 bytes, checksum: fcbb9a4336522af9d68dd7cdd4ded487 (MD5) Approved for entry into archive by Delba Rosa (delba@ufba.br) on 2018-05-04T14:23:31Z (GMT) No. of bitstreams: 1 ANTI-LIVER CANCER ACTIVITY IN VITRO AND IN VIVO INDUCED BY 2-PYRIDYL 2,3-THIAZOLE DERIVATIVES.pdf: 2793458 bytes, checksum: fcbb9a4336522af9d68dd7cdd4ded487 (MD5) Made available in DSpace on 2018-05-04T14:23:31Z (GMT). No. of bitstreams: 1 ANTI-LIVER CANCER ACTIVITY IN VITRO AND IN VIVO INDUCED BY 2-PYRIDYL 2,3-THIAZOLE DERIVATIVES.pdf: 2793458 bytes, checksum: fcbb9a4336522af9d68dd7cdd4ded487 (MD5) A total of 24 hybrid compounds containing pyridyl and 1,3-thiazole moieties were screened against HL-60 (leukemia), MCF-7 (breast adenocarcinoma),HepG2 (hepatocellular carcinoma), NCI-H292 (lung carcinoma) human tumor cell lines and non-tumor cells (PBMC, human peripheral blood mononuclear cells). Most of them were highly potent in at least one cell line tested (IC50 ≤ 3 μM), being HL-60 the most sensitive and HepG2 the most resistant cell line. Among them, TAP-07 and TP-07 presented cytotoxic activity in all tumor cell lines, including HepG2 (IC50 2.2 and 5.6 μM, respectively) without antiproliferative effects to normal cells (PBMC) (IC50 N 30 μM),making TAP-07 and TP-07, the compounds with the most favorable selectivity index. TAP-07 and TP-07 induced apoptosis in HepG2 cells and presented in vivo antitumor activity in hepatocellular xenograft cancer model in C.B-17 severe combined immunodeficientmice. Systemic toxicological verified by biochemical and histopathological techniques reveled nomajor signs of toxicity after treatmentwith TAP-07 and TP-07. Together the results indicated the anti-liver cancer activity of 2-pyridyl 2,3-thiazole derivatives.

Guatteria megalophylla Diels (Annonaceae) is an 8−10 m tall tree that grows near streams and is widely spread throughout Colombian, Ecuadorian, Peruvian, Brazilian and Guianese Amazon rainforest. Herein, we investigated for the first time the chemical composition and in vitro and in vivo anti-leukemia potential of G. megalophylla leaf essential oil (EO) using human promyelocytic leukemia HL-60 cells as model. EO was obtained by a hydrodistillation clevenger-type apparatus and characterized quali- and quantitatively by GC–MS and GC–FID, respectively. In vitro cytotoxic potential of EO was evaluated in human cancer cell lines (HL-60, MCF-7 CAL27, HSC-3, HepG2 and HCT116) and in human non-cancer cell line (MRC-5) by Alamar blue method. Annexin V/propidium iodide staining, cell cycle distribution and reactive oxygen species (ROS) were assessed by flow cytometry for HL-60 cells treated with EO. In vivo efficacy of EO (50 and 100 mg/kg) was evaluated in C.B-17 SCID mice with HL-60 cell xenografts. Chemical composition analyses showed spathulenol, γ-muurolene, bicyclogermacrene, β-elemene and δ-elemene as main constituents of assayed sample. EO displayed in vitro cytotoxicity, including anti-leukemia effect with IC50 value of 12.51 μg/mL for HL-60 cells. EO treatment caused augment of phosphatidylserine externalization and DNA fragmentation without increasing of ROS in HL-60 cells. In vivo tumor mass inhibition rates of EO was 16.6–48.8 %. These data indicate anti-leukemia potential of G. megalophylla leaf EO.