Non-coding RNAs play a critical role in gene regulation in cancer cells. Reduced expression of microRNA-192 (miR-192) has been detected in many cancers. In this study, we investigated the role of miR-192 in cell proliferation and cell cycle control in NALM-6 cell line, a model of acute lymphoblastic leukemia (ALL). Cell cycle analysis by DNA content using propidium iodide staining and cell apoptosis analysis using Annexin V assay were carried out. Cell proliferation changes were monitored using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In addition, the relative changes in P53, BAX, CASP3, and BCL-2 gene expression were determined by quantitative reverse transcription PCR. Overexpression of miR-192 resulted in cell proliferation arrest in ALL cells. After 72 and 96 hours of transduction, apoptosis was significantly increased in the cells transduced with miR-192-overexpressing virus compared with control cells. The expression of P53, BAX, and CASP3 increased after 48 hours of transduction in miR-192-overexpressing cells, but no change was observed in BCL-2 expression. The G0/S and G1/S ratio changed to 7.5 and 4.5, respectively, in the cells overexpressing miR-192 compared with controls. The results of our study suggest, for the first time, tumor suppressive effects of miR-192 in ALL cells.

Spermatogonial cells (SCs) are key cells for spermatogenesis. These cells are affected by paracrine signals originated from nearby somatic cells, among them Leydig cells have receptors for osteocalcin, a hormone known for exerting positive roles in the promotion of spermatogenesis. The aim of this study was to evaluate roles for osteocalcin on SCs proliferative and differentiation features after coculture with Leydig cells. SCs and Leydig cells were isolated from neonate NMRI offspring mice and adult NMRI mice, respectively. SCs population were then enriched in a differential attachment technique and assessed for morphological features and identity. Then, SCs were cocultured with Leydig cells and incubated with osteocalcin for 4 weeks. Evaluation of proliferation and differentiation‐related factors were surveyed using immunocytochemistry (ICC), Western blot, and quantitative real‐time polymerase chain reaction (PCR). Finally, the rate of testosterone release to the culture media was measured at the end of 4th week. Morphological and flow cytometry results showed that the SCs were the population of cells able to form colonies and to express ID4, α6‐, and β1‐integrin markers, respectively. Leydig cells were also able to express Gprc6α as a specific marker for the cells. Incubation of SCs/Leydig coculture with osteocalcin has resulted in an increase in the rate of expressions for differentiation‐related markers. Levels of testosterone in the culture media of SCs/Leydig was positively influenced by osteocalcin. It could be concluded that osteocalcin acts as a positive inducer of SCs in coculture with Leydig cells probably through stimulation of testosterone release from Leydig cells and associated signaling.

No abstract

Introduction: Chronic myelogenous leukemia (CML) is a myeloproliferative disorder caused by the Philadelphia chromosome translocation, at (9; 22), which results in BCR-ABL fusion tyrosine kinase oncoprotein. This fusion induces down-regulation of miR-155. Upregulation of miR-155 can influence cell fate via the effect on p27kip1 and apoptosis. The aim of this study was to induce apoptosis in K562 CML cell line by overexpression of miR-155. Methods: The K562 cell line was transfected with pLenti-III-pre mir155-GFP constructs through electroporation. Then, overexpression of miR-155 as well as the expression level of p27kip1 and c-Myc was analyzed by quantitative PCR (qPCR). The level of p27 (Kip1) protein expression was measured by Western blot and the Annexin V method was carried out to investigate apoptosis. Results: Flow cytometric analysis results of K562 cells transfected with pLenti-III-pre mir155-GFP construct showed a significant increase in cell apoptosis. Gene expression and protein level of p27kip1 were upregulated. However, there was no change in c-Myc expression profile. Conclusion: miR-155 could be a promising approach to aid in the treatment of CML. However, further studies are required in this respect.

No abstract