OBJECTIVES: The aim of this study was to determine the antiproliferative and apoptotic effects of hot water extracts of Chlorella vulgaris on hepatoma cell line HepG2. INTRODUCTION: The search for food and spices that can induce apoptosis in cancer cells has been a major study interest in the last decade. Chlorella vulgaris, a unicellular green algae, has been reported to have antioxidant and anti-cancer properties. However, its chemopreventive effects in inhibiting the growth of cancer cells have not been studied in great detail. METHODS: HepG2 liver cancer cells and WRL68 normal liver cells were treated with various concentrations (0-4 mg/ ml) of hot water extract of C. vulgaris after 24 hours incubation. Apoptosis rate was evaluated by TUNEL assay while DNA damage was assessed by Comet assay. Apoptosis proteins were evaluated by Western blot analysis. RESULTS: Chlorella vulgaris decreased the number of viable HepG2 cells in a dose dependent manner (p < 0.05), with an IC50 of 1.6 mg/ml. DNA damage as measured by Comet assay was increased in HepG2 cells at all concentrations of Chlorella vulgaris tested. Evaluation of apoptosis by TUNEL assay showed that Chlorella vulgaris induced a higher apoptotic rate (70%) in HepG2 cells compared to normal liver cells, WRL68 (15%). Western blot analysis showed increased expression of pro- apoptotic proteins P53, Bax and caspase-3 in the HepG2 cells compared to normal liver cells WRL68, and decreased expression of the anti-apoptotic protein Bcl-2. CONCLUSIONS: Chlorella vulgaris may have anti-cancer effects by inducing apoptosis signaling cascades via an increased expression of P53, Bax and caspase-3 proteins and through a reduction of Bcl-2 protein, which subsequently lead to increased DNA damage and apoptosis. � 2010 CLINICS.

Objectives: Streptococcus pneumoniae causes acute otitis media, pneumonia, meningitis and bacteraemia. This study aimed to determine the prevalence of Streptococcus pneumoniae oropharyngeal carriage in healthy children and the antimicrobial susceptibility in a daycare nursery and a government-managed orphanage in Kuala Lumpur during 2010.Methods: Throat swabs were obtained from 36 children of daycare nursery (open community) and from 84 orphans from orphanage (closed community) those did not receive any pneumococcal vaccine. Children were between births to 6 years of age. Antibiotic susceptibility of isolated strains was determined using disk diffusion method and Etest� (minimum inhibitory concentration). Results: Overall prevalence of Streptococcus pneumoniae of the children was 1.7% (2 out of 120). Prevalence of the bacteria in open community was 5.6% (2 out of 36) and no positive cases were recorded in orphanage (closed community, (p=0.161). Prevalence was 15.4% (2 out of 13) in children aged below 2 years in the open community. There was no association was found to exist between Streptococcus pneumoniae carriage with age (p=0.432) and gender (p=0.418). Serotyping showed serotype 11F for one isolate, while the other was non-typable. Both isolates were susceptible to penicillin, azithromycin, ceftriaxone and vancomycin. The serotype 11F isolate was susceptible while the non-typable isolate was resistant to erythromycin.Conclusions: The results demonstrated low prevalence of Streptococcus pneumoniae in healthy children. These findings may complement other studies to explore further risk factors for colonisation, antimicrobial susceptibility and serotype distribution of Streptococcus pneumoniae to help for the planning of immunization strategies.