Two gene networks help control human intelligenceAbout 40% of variation in human intelligence is inherited, but isolating the genes responsible has been a daunting task. Now, researchers have leveraged vast amounts of genetic and behavioral data to identify two networks of genes that seem to contribute to higher brain functions, The Guardian reports. The networks are implicated in both neurodevelopmental disorders and normal variation in cognitive abilities, the researchers reported Monday in Nature Neuroscience. Perhaps most exciting, the networks are likely to share the same regulatory systema system that researchers could potentially target to treat conditions such as epilepsy and schizophrenia. Novas alternativas de combate ao CAEstudo publicado por cientistas demonstram que o uso de RNA de interferencia pode reduzir a proliferacao de tumores de cancer de prostata.\HUANG, S.Q. et al. RNAi-mediated knockdown of pituitary tumor- transforming gene-1 (PTTG1) suppresses the proliferation and invasive potential of PC3 human prostate cancer cells. Braz J Med Biol Res [online]. 2012, vol.45, n.11, pp. 995-1001. Epub Aug 09, 2012 ISSN 1414-431X. http://dx.doi.org/10.1590/S0100-879X2012007500126.Pituitary tumor-transforming gene-1 (PTTG1) is a proto-oncogene that promotes tumorigenesis and metastasis in numerous cell types and is overexpressed in a variety of human tumors. We have demonstrated that PTTG1 expression was up-regulated in both human prostate cancer specimens and prostate cancer cell lines. For a more direct assessment of the function of PTTG1 in prostate tumorigenesis, RNAi-mediated knockdown was used to selectively decrease PTTG1 expression in PC3 human prostate tumor cells. After three weeks of selection, colonies stably transfected with PTTG1-targeted RNAi (the knockdown PC3 cell line) or empty vector (the control PC3 cell line) were selected and expanded to investigate the role of PTTG1 expression in PC3 cell growth and invasion. Cell proliferation rate was significantly slower (28%) in the PTTG1 knockdown line after 6 days of growth as indicated by an MTT cell viability assay (P < 0.05). Similarly, a soft agar colony formation assay revealed significantly fewer (66.7%) PTTG1 knockdown PC3 cell colonies than control colonies after three weeks of growth. In addition, PTTG1 knockdown resulted in cell cycle arrest at G1 as indicated by fluorescence-activated cell sorting. The PTTG1 knockdown PC3 cell line also exhibited significantly reduced migration through Matrigel in a transwell assay of invasive potential, and down-regulation of PTTG1 could lead to increased sensitivity of these prostate cancer cells to a commonly used anticancer drug, taxol. Thus, PTTG1 expression is crucial for PC3 cell proliferation and invasion, and could be a promising new target for prostate cancer therapy.Keywords : PTTG1; Prostate cancer; Cell proliferation; Transwell invasion assay; Anticancer drug resistance. Bad luck not a major cause of cancer, new study saysIn January, two researchers at Johns Hopkins University in Baltimore, Maryland, (and the journalists who wrote about them) spurred a firestorm by writing in Science that much of cancer is due to bad luck, or random mistakes that take place when cells divide. That paper launched a lively debate, and today a group at the State University of New York at Stony Brook has fired back: The authors argue in Nature that the earlier analysis was flawed,