Antileukemic Effects of Anti-miR-146a, Anti-miR-155, Anti-miR-181a, and Prednisolone on Childhood Acute Lymphoblastic Leukemia.

Prednisolone has been used frequently in the treatment of acute lymphoblastic leukemia. However, to overcome the challenges of the treatment, the development of additional therapies is of great importance. Small, non-protein-coding RNAs, namely, microRNAs (miRNAs), are critical epigenetic regulators with physiological and pathological importance. This study is aimed at determining the effects of miR-146a, miR-155, and miR-181a inhibition with their corresponding anti-miRs on both leukemic and healthy cells, individually and with prednisolone. Leukemic (SUP-B15) and healthy B-lymphocyte (NCI-BL 2171) cell lines were used in this study. A total of 12 experimental groups included individual and combinational silenced ALL-associated miRNAs (hsa-miR-155, hsa-miR-146a, and hsa-miR-181a) and their combination with prednisolone. Cytotoxicity, proliferation, cell cycle, and apoptosis analyses were performed by using WST-1, trypan blue, APC-BrdU, Annexin V, and JC-1 methods in each study group, respectively. To control the effectiveness of anti-miR transfection and prednisolone application, miRNA expression analysis was performed from all groups. Anti-miR application was effective on the viability, proliferation, cell cycle, and apoptosis of leukemia cells, and this effect was increased with prednisolone administration. In addition, this activity was found to be very low on healthy cells. In conclusion, anti-miR applications may have the potential for clinical use of adjuvant to or as an alternative to conventional therapies for childhood acute lymphoblastic leukemia.

Sonic hedgehog signaling is associated with resistance to zoledronic acid in CD133high/CD44high prostate cancer stem cells.

Cancer stem cells (CSCs) are a unique population that has been linked to drug resistance and metastasis and recurrence of prostate cancer. The sonic hedgehog (SHH) signal regulates stem cells in normal prostate epithelium by affecting cell behavior, survival, proliferation, and maintenance. Aberrant SHH pathway activation leads to an unsuitable expansion of stem cell lineages in the prostate epithelium and the transformation of prostate CSCs (PCSCs). Zoledronic acid (ZOL), one of the third-generation bisphosphonates, effectively prevented bone metastasis and treated advanced prostate cancer despite androgen deprivation therapy. Despite strong evidence for the involvement of the SHH in human PCSCs survival and drug resistance, the roles of SHH in the PCSCs-related resistance to ZOL remain to be fully elucidated. The present study aimed to investigate the role of the SHH pathway in ZOL resistance of PCSCs in 2D and three 3D cell culture conditions. For this purpose, we isolated CD133high/ CD44high PCSCs using a flow cytometer. Following ZOL treatment, mRNA and protein expressions of the components of the SHH signaling pathway in PCSCs and non-CSCs were analyzed using qRT-PCR and Immunofluorescence staining, respectively. Our finding suggested that SHH signaling may be activated by different mechanisms that lead to avoidance of the inhibition effect of ZOL. Thereby, SHH pathways may be associated with the resistance to ZOL developed by prostate CSCs. Inhibition of CSCs-related SHH signaling along with ZOL treatment should be considered to achieve improvement in survival or delayed treatment failure and prevention of the CSCs-related drug resistance.