Are statins a risk factor in patients with atherosclerosis? / ¿Son las estatinas un factor de riesgo en pacientes con aterosclerosis?

SUMMARY: Statins inhibit cholesterol synthesis, but also have other pleiotropic effects. There are indications that they affect macrophage survival trough the regulation of apoptosis. We analyzed 50 samples of aortic wall, selected based on statins in patients' therapy (n=25, Th-S group) or statin-free therapy (n=25, Th-nonS group). Each group had 5 samples of healthy aortic tissue, 10 samples of mild and 10 samples of severe atherosclerotic changes in aortic wall. Tissue was stained with hematoxylin-eosin and immunohistochemical methods (anti-Bcl-2 antibody). Presence of Bcl2-positive macrophages (Bcl-2+ MP) was determined semiquantitatively, and data were processed in Microsoft Excell and IMB SPSS 23 Statistics. 60 % of patients in the Th-S group had a mild increase of Bcl-2+ MP The use of statins leads to a significantly more frequent increase in Bcl2+ macrophages in the intima of the healthy aortic tissue. Analysis of all aortic samples with pathohistological diagnosis showed that statin therapy was statistically significantly more often leading to a markedly increased presence of Bcl-2+ MP. In the media, all samples of the Th-S group have a mild increase of Bcl-2+ MP, and in adventitia 40 % of patients. The use of statins more often leads to a markedly increased presence of Bcl-2+ MP in aortic tissue with diagnosed mild and severe atherosclerosis. In samples of severe atherosclerosis, statins lead to a markedly increased presence of Bcl-2+ MP in the parts of the plaque towards the intima and towards the media. Statins lead to an increased presence of Bcl-2+ macrophages, prolong their life, both in healthy and atherosclerotic altered aortic tissue. This indicates potentiation of inflammation and damage to the aortic wall, and calls into question the positive effect of statins on the aortic wall with atherosclerosis.

RESUMEN: Las estatinas inhiben la síntesis de colesterol, pero también tienen otros efectos pleiotrópicos. Hay indicios de que afectan la supervivencia de los macrófagos a través de la regulación de la apoptosis.Se analizaron 50 muestras de pared aórtica, seleccionadas en base a estatinas en tratamiento de pacientes (n=25, grupo Th-S) o en tratamiento libre de estatinas (n=25, grupo Th- nonS). Cada grupo tenía 5 muestras de tejido aórtico sano, 10 muestras de cambios ateroscleróticos leves y 10 muestras de cambios ateroscleróticos severos en la pared aórtica. El tejido se tiñó con hematoxilina-eosina y métodos inmunohistoquímicos (anticuerpo anti-Bcl-2). La presencia de macrófagos positivos para Bcl2 (Bcl- 2+ MP) se determinó semicuantitativamente y los datos se procesaron en Microsoft Excell e IMB SPSS 23 Statistics. El 60 % de los pacientes del grupo Th-S tuvo un aumento leve de Bcl-2+ MP. El uso de estatinas conduce a un aumento significativamente más frecuente de macrófagos Bcl2+ en la íntima del tejido aórtico sano. El análisis de todas las muestras aórticas con diagnóstico anatomopatológico mostró que la terapia con estatinas fue significativamente más frecuente desde el punto de vista estadístico, lo que condujo a una presencia marcadamente mayor de Bcl-2+ MP. En los medios, todas las muestras del grupo Th-S tienen un leve aumento de Bcl-2+ MP, y en adventicia en el 40 % de los pacientes. El uso de estatinas con mayor frecuencia conduce a una presencia marcadamente mayor de MP Bcl-2+ en el tejido aórtico con aterosclerosis leve y grave diagnosticada. En muestras de aterosclerosis severa, las estatinas conducen a una presencia aumentada de Bcl-2+ MP en las partes de la placa hacia la íntima y hacia la media. Las estatinas conducen a una mayor presencia de macrófagos Bcl-2+, prolongan su vida, tanto en tejido aórtico sano como aterosclerótico alterado. Esto indica la potenciación de la inflamación y el daño a la pared aórtica y pone en duda el efecto positivo de las estatinas en la pared aórtica con aterosclerosis.

MicroRNA-153-3p enhances cell radiosensitivity by targeting BCL2 in human glioma

BACKGROUND: Glioma is the most prevalent malignant tumor in human central nervous systems. Recently, the development of resistance to radiotherapy in glioma patients markedly vitiates the therapy outcome. MiR-153-3p has been reported to be closely correlated with tumor progression, but its effect and molecular mechanism underlying radioresistance remains unclear in glioma. METHODS: The expression of miR-153-3p was determined in radioresistant glioma clinical specimens as well as glioma cell lines exposed to irradiation (IR) using quantitative real-time PCR. Cell viability, proliferation and apoptosis were then evaluated by MTT assay, colony formation assay, Flow cytometry analysis and caspase-3 activity assay in glioma cells (U87 and U251). Tumor forming was evaluated by nude mice model in vivo. TUNEL staining was used to detect cell apoptosis in nude mice model. The target genes of miR-153-3p were predicted and validated using integrated bioinformatics analysis and a luciferase reporter assay. RESULTS: Here, we found that miR-153-3p was down-regulated in radioresistant glioma clinical specimens as well as glioma cell lines (U87 and U251) exposed to IR. Enhanced expression of miR-153-3p promoted the radiosensitivity, promoted apoptosis and elevated caspase-3 activity in glioma cells in vitro, as well as the radiosensitivity in U251 cell mouse xenografs in vivo. Mechanically, B cell lymphoma-2 gene (BCL2) was identified as the direct and functional target of miR-153-3p. Moreover, restoration of BCL2 expression reversed miR-153-3p-induced increase of radiosensitivity, apoptosis and caspase-3 activity in U251 cells in vitro. In addition, clinical data indicated that the expression of miR-153-3p was significantly negatively associated with BCL2 in radioresistance of glioma samples. CONCLUSIONS: Our findings suggest that miR-153-3p is a potential target to enhance the effect of radiosensitivity on glioma cells, thus representing a new potential therapeutic target for glioma.

Cytotoxic and apoptotic potential of Myristica fragrans Houtt. (mace) extract on human oral epidermal carcinoma KB cell lines

Several studies have revealed that certain naturally occurring medicinal plants inhibit the growth of various cancers. The present study was conducted to evaluate cytotoxicity and apoptotic induction potential of Myristica fragrans Houtt mace extract. The cytotoxic activity of the Myristica fragrans Houtt mace acetone extract was assayed by MTT assay on human oral epidermal carcinoma KB cell lines. KB cells were incubated with different concentration of mace extract ranging from 25 to 125 µg/mL for 24hrs. The apoptotic induction potential was also studied by the analysis of Bcl-2 protein and gene expression in mace extract incubated KB cell lines using western blotting technique and real-time polymerase chain reaction. The mace extract exhibited cytotoxicity and anticancer effect against KB cell lines and it also suppressed the growth of cancer cells, therefore growth inhibitory effect was noted in extract treated cell lines. The apoptotic potential of mace extract was accompanied by reduced gene expression of Bcl-2 compared to the untreated KB cells. The mace extract shows the cytotoxic activity and induced the apoptosis through the modulation of its target genes Bcl-2 in the KB cell lines, suggesting the potential of mace as a candidate for oral cancer chemoprevention. This can be further investigated in vivo for its anticancer potential.