Species-specific KRAB-ZFPs function as repressors of retroviruses by targeting PBS regions.

SignificanceHosts often target the relatively conserved regions in rapidly mutating retroviruses to inhibit their replication. One of these regions is called a primer binding site (PBS), which has to be complementary to the host tRNA to initiate reverse transcription. By analyzing endogenous retroviral elements, we found that host cells use this sequence as a target in efforts to block the expression of viral elements. A specific type of zinc finger protein targets the PBS in a host genome, which not only inhibits the transcription of endogenous viruses but also inhibits the replication of exogenous retroviruses with the same PBS. Thus, our study sheds light on a strategy for searching for host restriction factors targeting retroviruses.

An Insight on Synergistic Anti-cancer Efficacy of Biochanin A and Sulforaphane Combination Against Breast Cancer.

Breast cancer is a serious malignancy that has higher rate of morbidity and mortality. It has been known to affect the women indifferently. The lack and side effects in the current therapeutic modules result in the search of the wide treatment options including combinatorial treatment. The goal of this study was to investigate combinatorial anti-proliferative efficacy of biochanin A (BCA) and sulforaphane (SFN) against MCF-7 breast cancer cells. The study involves the utilisation of various qualitative techniques including cytotoxicity analysis (MTT), morphogenic analysis, AO/EtBr, DAPI, ROS, cell cycle, and cell migration analysis in order to examine the combinatorial efficacy of BCA and SFN in inducing the cell death. The results had shown that the cytotoxicity of BCA and SFN was found to be around 24.5 µM and 27.2 µM respectively, while the combination of BCA and SFN had shown an inhibitory activity at about 20.1 µM. And furthermore, AO/EtBr and DAPI had shown a profound increase in apoptogenic activity of compounds when treated in combination at lower dose. This apoptogenic activity may be attributed to the increased ROS production. Moreover, it has been shown that the BCA and SFN have been involved in the down-regulation of ERK-1/2 signalling pathway resulting in induction of apoptosis of cancer cells. Thus, our results had concluded that BCA and SFN co-treatment could be used as an efficient therapeutic target against breast cancer. Furthermore, in vivo efficiency by which the co-treatment induces apoptosis has to be deliberated further in near future to make their use commercially.