Selective cytotoxic and genotoxic activities of 5-(2-bromo-5-methoxybenzylidene)-thiazolidine-2,4-dione against NCI-H292 human lung carcinoma cells.

BACKGROUND: Thiazolidine-2,4-dione ring system is used as a pharmacophore to build various heterocyclic compounds aimed to interact with biological targets. In the present study, benzylidene-2,4-thiazolidinedione derivatives (compounds 2-5) were synthesized and screened against cancer cell lines and the genotoxicity and cytotoxicity of the most active compound (5) was investigated on normal and lung cancer cell line. METHODS: For in vitro cytotoxic screening, the MTT assay was used for HL60 and K562 (leukemia), MCF-7 (breast adenocarcinoma), HT29 (colon adenocarcinoma), HEp-2 (cervix carcinoma) and NCI-H292 (lung carcinoma) tumor cell lines and Alamar-blue assay was used for non-tumor cells (PBMC, human peripheral blood mononuclear cells) were used. Cell morphology was visualized after Giemsa-May-Grunwald staining. DNA content, phosphatidylserine externalization and mitochondrial depolarization were measured by flow cytometry. Genotoxicity was assessed by Comet assay. RESULTS: 5-(2-Bromo-5-methoxybenzylidene)-thiazolidine-2,4-dione (5) presented the most potent cytotoxicity, especially against NCI-H292 lung cancer cell line, with IC50 value of 1.26µg/mL after 72h incubation. None of the compounds were cytotoxic to PBMC. After 48h incubation, externalization of phosphatidylserine, mitochondrial depolarization, internucleosomal DNA fragmentation and morphological alterations consistent with apoptosis were observed in NCI-H292 cells treated with compound (5). In addition, compound (5) also induced genotoxicity in NCI-H292 cells (2.8-fold increase in damage index compared to the negative control), but not in PBMC. CONCLUSION: Compound 5 presented selective cytotoxic and genotoxic activity against pulmonary carcinoma (NCI-H292 cells).

Treatment with pCramoll Alone and in Combination with Fluconazole Provides Therapeutic Benefits in C. gattii Infected Mice.

Cryptococcus gattii is one of the main causative agents of cryptococcosis in immunocompetent individuals. Treatment of the infection is based on the use of antimycotics, however, the toxicity of these drugs and the increase of drug-resistant strains have driven the search for more effective and less toxic therapies for cryptococcosis. pCramoll are isolectins purified from seeds of Cratylia mollis, a native forage plant from Brazil, which has become a versatile tool for biomedical application. We evaluated the effect of pCramoll alone and in combination with fluconazole for the treatment of mice infected with C. gatti. pCramoll alone or in combination with fluconazole increased the survival, reduced the morbidity and improved mice behavior i.e., neuropsychiatric state, motor behavior, autonomic function, muscle tone and strength and reflex/sensory function. These results were associated with (i) decreased pulmonary and cerebral fungal burden and (ii) increased inflammatory infiltrate and modulatory of IFNγ, IL-6, IL-10, and IL-17A cytokines in mice treated with pCramoll. Indeed, bone marrow-derived macrophages pulsed with pCramoll had increased ability to engulf C. gattii, with an enhanced production of reactive oxygen species and decrease of intracellular fungal proliferation. These findings point toward the use of pCramoll in combination with fluconazole as a viable, alternative therapy for cryptococcosis management.