Overexpression of ABCB1 confers resistance to FLT3 inhibitor FN-1501 in cancer cells: in vitro and in vivo characterization.

FN-1501 is a potent FLT3 inhibitor with antitumor activity. A phase 1 trial of FN-1501 monotherapy in patients with advanced solid tumors and R/R AML is in progress. Since one of the primary causes of multidrug resistance (MDR) is the overexpression of ATP-binding cassette superfamily B member 1 (ABCB1), the objective of this study was to investigate the potential relationship between FN-1501 and the ABCB1 transporter. We found ABCB1 overexpressing-cancer cells conferred FN-1501 resistance, which could be reversed by an ABCB1 inhibitor. Molecular docking study revealed that FN-1501 docked the ligand binding site with an affinity score of -9.77 kcal/mol, denoting a strong interaction between FN-1501 and ABCB1. Additionally, the ABCB1 ATPase assay indicated that FN-1501 could significantly stimulate ABCB1 ATPase activity. Furthermore, we observed a similar trend of ABCB1-facilated FN-1501 resistance in tumor-bearing mice model. In sum, we demonstrate that FN-1501 is a substrate of ABCB1 transporter from both in vivo and in vitro studies. Therefore, our findings provide new insight on the mechanism of chemoresistance due to ABCB1 overexpression.

[ZNF185 gene cloning and the localization in mouse testis].

AIM: we Clone the ZNF185 gene and detect the position of ZNF185 in the mouse testis. METHODS: extracted from mouse testis RNA, by RT-PCR, and then the obtained fragment was cloned and identified; extracted from mouse liver, testis and ovary proteins were Western blot analysis; preparation of frozen sections of mouse testes, immunofluorescence techniques analysis. RESULTS: (1) ZNF185 gene cloning was correct. (2) Western blot showed that the most abundant in the testes ZNF185. (3) Immunofluorescence showed, ZNF185 located in Leydig cells and sperm, Leydig cells in the weak, and in round spermatids and mature sperm were highly expressed. CONCLUSION: the gene cloning of ZNF185 was successful and initially proved the position of ZNF185 in the mouse testis.

Interactive effects of granulosa cell apoptosis, follicle size, cumulus-oocyte complex morphology, and cumulus expansion on the developmental competence of goat oocytes: a study using the well-in-drop culture system.

Using a well-in-drop (WID) oocyte/embryo culture system that allows identification of follicular origin, we have investigated the effects of granulosa cells (GCs) apoptosis, follicle size, cumulus-oocyte complexes (COCs) morphology, and cumulus expansion on the developmental competence of goat oocytes matured and cultured individually following parthenogenetic activation. The WID system supported oocyte maturation and embryo development to a level similar to the conventional group system. The majority of goat oocytes acquired competence for development up to the 8-16 cell stage in follicles larger than 2 mm, but did not gain the ability to form morula/blastocyst (M/Bs) until follicles larger than 3 mm in diameter. The extent of atresia affected M/Bs formation. This effect varied according to the follicle size. Cumulus expansion increased with follicle size and decreased with increasing incidence of GCs apoptosis. Oocyte developmental potential was also correlated with cumulus expansion. Regardless of the degree of follicle atresia, 73-84% of the floating cells in the follicular fluid (FF) underwent apoptosis. Correlation between floating cell density in FF and oocyte developmental potency suggests the possibility to use the floating cell density as a simple and non-invasive marker for oocyte quality. It is concluded that the developmental potential of an oocyte is determined by multifactor interactions, and multiple factors must be considered together to accurately predict the quality of an oocyte.

cAMP elevators inhibit LPS-induced IL-12 p40 expression by interfering with phosphorylation of p38 MAPK in murine peritoneal macrophages.

cAMP mediated signaling may play a suppressive role in immune response. We previously found that the cAMP-elevators (CTx and 8-Br-cAMP) inhibited IL-12, IL-la, IL-6 gene expression, but increased the transcriptional levels of IL-10 and IL-1Ra in LPS-treated murine peritoneal macrophages. The present study examined a possible molecular mechanism involved in cAMP elevators-induced inhibition of IL-12 p40 expression in response to LPS. Our data demonstrated that cAMP elevators downregulated IL-12 p40 mRNA expression and IL-12 p70 production in murine peritoneal macrophages. Subsequent studies revealed that cAMP-elevators blocked phosphorylation of p38 MAPK, but did not affect the activity of NF-kappaB binding to IL-12 promoter (-136/-112). This is the first report that cAMP elevators inhibit LPS-induced IL-12 production by a mechanism that is associated, at least in part, with p38-dependent inhibition by cAMP signaling pathways.