ABSTRACT
Besides the fundamental components of the chromatin, DNA and octameric histone, the non-histone chromatinproteins and non-coding RNA play a critical role in the organization of functional chromatin domains. Thenon-histone chromatin proteins therefore regulate the transcriptional outcome in both physiological andpathophysiological state as well. They also help to maintain the epigenetic state of the genome indirectly.Several transcription factors and histone interacting factors also contribute in the maintenance of the epigeneticstates, especially acetylation by the induction of autoacetylation ability of p300/CBP. Alterations of KATactivity have been found to be causally related to disease manifestation, and thus could be potential therapeutictarget.
ABSTRACT
The Aurora kinases represent a group of serine/threonine kinases which are crucial regulators of mitosis. DysregulatedAurora kinase B (AurkB) expression, stemming from genomic amplification, increased gene transcription or overexpressionof its allosteric activators, is capable of initiating and sustaining malignant phenotypes. Although AurkB level in cells iswell-orchestrated, studies that relate to its stability or activity, independent of mitosis, are lacking. We report that AurkBundergoes acetylation in vitro by lysine acetyltransferases (KATs) belonging to different families, namely by p300 andTip60. The haploinsufficient tumor suppressor Tip60 acetylates two highly conserved lysine residues within the kinasedomain of AurkB which not only impinges the protein stability but also its kinase activity. These results signify a probableoutcome on the increase in ‘‘overall activity’’ of AurkB upon Tip60 downregulation, as observed under cancerous conditions. The present work, therefore, uncovers an important functional interplay between AurkB and Tip60, frailty of whichmay be an initial event in carcinogenesis.
ABSTRACT
Background & objectives: The complementary and alternative medicines (CAM) have not been systematically evaluated for the management of HIV/AIDS patients. In a prospective, single-site, open-label, non-randomized, controlled, pilot trial, we evaluated a polyherbal formulation (PHF) for its safety and efficacy in treating subjects with HIV-AIDS. Methods: A total of 32 and 31 subjects were enrolled under the PHF and highly active antiretroviral treatment (HAART) arms, respectively, and followed up for a period of 24 months. Plasma viral RNA, CD4 cell count and blood chemistry were monitored at 3-month intervals. Following mid-term safety evaluation, 12 subjects from the PHF arm were shifted to HAART and were followed separately as PHF-to-HAART arm, for the rest of the period. Results: The HAART arm was characterized by significant improvements in CD4 cell count (154.4 cells/μl/year, P<0.001) and reduction in plasma viral load within 3 to 6 months (-0.431+ 0.004 log10 IU/month, P<0.001). In contrast, the PHF arm showed a profile of CD4 cell loss at remarkably slower kinetics (14.3 cells/μl/year, P=0.021) and insignificant reduction in the viral load. The PHF and HAART arms did not differ significantly in the occurrence of AIDS-related illnesses over the study period of 24 months. In the PHF-to-HAART arm, the rates of CD4 count and reduction in viral load were significant and comparable to that of the HAART group. In the PHF arm, at 1 month, a significant increase in CD4 cell count and a concomitant decrease in viral load were seen. Interpretation & conclusions: The PHF appears to have provided protection by delaying the kinetics of CD4 cell reduction. Given the several study limitations, drawing assertive inferences from the data is challenging. Future studies with a stringent study design are warranted to confirm these findings.