Animal cloning can be achieved through somatic cell nuclear transfer (SCNT), although the live birth rate is relatively low. Recent studies have identified H3K9me3 in donor cells and abnormal Xist activation as epigenetic barriers that impede SCNT. Here we overcome these barriers using a combination of Xist knockout donor cells and overexpression of Kdm4 to achieve more than 20% efficiency of mouse SCNT. However, post-implantation defects and abnormal placentas were still observed, indicating that additional epigenetic barriers impede SCNT cloning. Comparative DNA methylome analysis of IVF and SCNT blastocysts identified abnormally methylated regions in SCNT embryos despite successful global reprogramming of the methylome. Strikingly, allelic transcriptomic and ChIP-seq analyses of pre-implantation SCNT embryos revealed complete loss of H3K27me3 imprinting, which may account for the postnatal developmental defects observed in SCNT embryos. Together, these results provide an efficient method for mouse cloning while paving the way for further improving SCNT efficiency.

SummaryAstrocytes, due to the proximity to neuronal lineage and capability to proliferate, are ideal starting cells to regenerate neurons. Human fetal astrocytes have been successfully converted into neuronal cells by small molecules, which offered a broader range of further applications than transcription factor-mediated neuronal reprogramming. Here we report that human adult astrocytes could also be converted into neuronal cells by a different set of small molecules. These induced cells exhibited typical neuronal morphologies, expressed neuronal markers, and displayed neuronal electrophysiological properties. Genome-wide RNA-sequencing analysis showed that the global gene expression profile of induced neuronal cells resembled that of human embryonic stem cell-differentiated neurons. When transplanted into post-natal mouse brains, these induced neuronal cells could survive and become electrophysiologically mature. Altogether, our study provides a strategy to directly generate transgene-free neuronal cells from human adult astrocytes by small molecules.

Background: Acquired proteasome inhibitor resistance emerges in myeloma patients through incompletely understood mechanisms. Results: Activation of nuclear factor (erythroid-derived 2)-like 2 (NRF2) and proteassemblin (POMP) was linked to bortezomib resistance, while their inhibition reversed resistance. Conclusion:The NRF2/POMP axis contributes to bortezomib resistance. Significance: NRF2/POMP axis inhibition can be translated to the clinic to reverse bortezomib resistance and induce chemosensitization.

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Bromodomain and extraterminal (BET) domain containing protein (BRD)-4 modulates the expression of oncogenes such as c-myc, and is a promising therapeutic target in diverse cancer types. We performed pre-clinical studies in myeloma models with bi-functional protein-targeting chimeric molecules (PROTACs) which target BRD4 and other BET family members for ubiquitination and proteasomal degradation. PROTACs potently reduced the viability of myeloma cell lines in a time- and concentration-dependent manner associated with G0/G1 arrest, reduced levels of CDKs 4 and 6, increased p21 levels, and induction of apoptosis. These agents specifically decreased cellular levels of downstream BRD4 targets, including c-MYC and N-MYC, and a Cereblon-targeting PROTAC showed downstream effects similar to those of an immunomodulatory agent. Notably, PROTACs overcame bortezomib, dexamethasone, lenalidomide, and pomalidomide resistance, and their activity was maintained in otherwise isogenic myeloma cells with wild-type or deleted TP53. Combination studies showed synergistic interactions with dexamethasone, BH3 mimetics, and Akt pathway inhibitors. BET-specific PROTACs induced a rapid loss of viability of primary cells from myeloma patients, and delayed growth of MM1.S-based xenografts. Our data demonstrate that BET degraders have promising activity against pre-clinical models of multiple myeloma, and support their translation to the clinic for patients with relapsed and/or refractory disease.

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Background Accumulating evidence suggests that plant-derived molecules may prove extremely beneficial in the development of chemotherapy for deadly cancer types. Multiple myeloma is a rare and incurable type of cancers. Very little research has been directed towards the development of chemotherapy for the management of multiple myeloma. Here, the anticancer effects of a plant-derived triterpenoid, Asiaticoside, were examined against the drug-resistant myeloma cell line KM3/BTZ. Material/Methods Cell viability was determined by CCK-8 assay and autophagy was checked by transmission electron microscopy. ROS levels were determined by flow cytometery. Cell migration and invasion were examined by Transwell assay. Protein expression was assessed by Western blotting. Results The results showed that Asiaticoside inhibits the growth of the KM3/BTZ cells and exhibited an IC 50 of 12 μM. Further, it was observed that the anticancer effects of Asiaticoside are due to the induction of autophagy allied with upsurge of the expression of LC3-II. Moreover, the expression of the effector caspases in the KM3/BTZ cells was also altered. Asiaticoside also caused accretion of the ROS in the KM3/BTZ cells and inhibited their migratory and invasive properties via modulation of the STAT-3 signaling pathway. Conclusions Asiaticoside may prove useful in the management and treatment of the multiple myeloma and needs further investigation.

The present study was undertaken to determine the molecular mechanisms by which embelin induces apoptosis in human leukemia cells. Embelin resulted in loss of cell viability and inhibition of proliferation in a dose- and time-dependent manner, which was largely attributed to apoptosis. Embelin caused depolarization of mitochondrial membrane potential. Western blot analysis showed that the expression of anti-apoptotic proteins X-linked inhibitor of apoptosis (XIAP) was down-regulated by embelin. Embelin induced activation of caspase-9 and embelin-induced apoptosis was prevented by caspase inhibitors. Taken together, these findings suggest that embelin results in human leukemia cells apoptosis through caspase-dependent mechanisms involving down-regulation of XIAP.