Anti-gp130 (S778) Antibody (A25546)

Acute erythroid leukemia (AEL) is characterized by lower incidence, poorer prognosis and worse survival than other types of leukemia and results from collaboration of malignant proliferation and erythroid differentiation blockage. The expression, function and therapeutic significance of noncoding RNAs in AEL have not been well studied. Here, we show that one miRNA cluster, including miR-23a, -27a and -24, is dramatically downregulated in AEL patients. Restoration of miR-23a, -27a and -24 expression induces apoptosis and erythropoiesis, inhibits adverse growth and partly relieves the leukemic symptoms of AEL patients. At the whole-genome scale, we identify that miR-23a, -27a and -24 synergistically target multiple members of the oncogenic gp130-JAK1-Stat3 pathway, and thus reinforce their inhibition on the cascade to regulate cell proliferation and apoptosis. Importantly, Ruxolitinib, a JAK1 inhibitor, could rescue the phenotypic changes induced by miR-23a, -27a and -24 inhibitors. Furthermore, miR-23a cluster-mediated-inactivation of the JAK1-Stat3 pathway promotes the expression and activity of GATA1 via inhibiting PU.1, thereby improving erythroid differentiation. Collectively, we reveal an important regulatory circuit comprising GATA1, the miR-23a cluster and gp130-JAK1-Stat3 pathway, that synergistically facilitates apoptosis and erythropoiesis and restrains adverse proliferation, indicating the therapeutic significance of miR-23a, -27a and -24 for AEL treatment.

We have previously demonstrated the growth-promoting effect of intrathecal delivery of recombinant rat IL-6 immediately after corticospinal tract (CST) injury. Our present study aims to further clarify whether intrathecal delivery of IL-6 after CST injury could reactivate the intrinsic growth capacity of pyramidal cells in the sensorimotor cortex which project long axons to the spinal cord. We examined, by ELISA, levels of cyclic adenosine monophosphate (cAMP), adenylyl cyclase (AC, which synthesizes cAMP), phosphodiesterases (PDE, which degrades cAMP), and, by RT-PCR, the expression of regeneration-associated genes in the rat sensorimotor cortex after intrathecal delivery of IL-6 for 7 days, started immediately after CST injury. Furthermore, we injected retrograde neuronal tracer Fluorogold (FG) to the spinal cord to label pyramidal cells in the sensorimotor cortex, layers V and VI, combined with βIII-tubulin immunostaining, then we analyzed by immunohistochemisty and western blot the expression of the co-receptor gp-130 of IL-6 family, and pSTAT3 and mTOR, downstream IL-6/JAK/STAT3 and PI3K/AKT/mTOR signaling pathways respectively. We showed that intrathecal delivery of IL-6 elevated cAMP level and upregulated the expression of regeneration-associated genes including GAP-43, SPRR1A, CAP-23 and JUN-B, and the expression of pSTAT3 and mTOR in pyramidal cells of the sensorimotor cortex. In contrast, AG490, an inhibitor of JAK, partially blocked these effects of IL-6. All these results indicate that intrathecal delivery of IL-6 immediately after spinal cord injury can reactivate the intrinsic growth capacity of pyramidal cells in the sensorimotor cortex and these effects of IL-6 were partially JAK/STAT3-dependent.