Synthesis and Biological Evaluation of Thienopyrrolizines, a New Family of CDK/GSK-3 Inhibitors

Sensitization of ovarian carcinoma cells to Bcl-xL-targeting strategies through indirect modulation of Mcl-1 activity by MR22388, a molecule of the tripentone family

Background

Our work has been carried out in the context of the therapeutic failure in ovarian carcinoma, which remains the leading cause of death by gynecologic malignancy. In these tumours, recurrence and subsequent acquired chemoresistance constitute major hurdles to successful therapy. Here we studied the interest of a member of the tripentone chemical family, MR22388, for the treatment of chemoresistant ovarian cancer cells.

Findings

MR22388 activity has been assessed in vitro on cisplatin-resistant (SKOV3 and IGROV1-R10) ovarian cancer cell lines by conventional analysis, alone or combined to a BH3-mimetic molecule, ABT-737. MR22388 exerts its activity on cisplatin resistant cells, and we showed that it induces a decrease of the Mcl-1 anti-apoptotic protein expression. Considering our previous work demonstrating that the efficiency of Bcl-x_L targeting strategies is conditioned to the concomitant inhibition of Mcl-1 we studied the interest of the association of this MR22388 with ABT-737, and showed that this combination was highly cytotoxic in chemoresistant cells.

Conclusions

This work thus opens new perspectives for the use of this promising molecule for the treatment of highly chemoresistant ovarian cancer cells and for sensitization of emerging Bcl-x_L targeting strategies such as the use of BH3-mimetic molecules.

Novel aryl and heteroaryl substituted N-[3-(4-phenylpiperazin-1-yl)propyl]-1,2,4-oxadiazole-5-carboxamides as selective GSK-3 inhibitors

Synthesis, biological evaluation, and SAR dependencies for a series of novel aryl and heteroaryl substituted N-[3-(4-phenylpiperazin-1-yl)propyl]-1,2,4-oxadiazole-5-carboxamide inhibitors of GSK-3beta kinase are described. The inhibitory activity of the synthesized compounds is highly dependent on the character of substituents in the phenyl ring and the nature of terminal heterocyclic fragment of the core molecular scaffold. The most potent compounds from this series contain 3,4-di-methyl or 2-methoxy substituents within the phenyl ring and 3-pyridine fragment connected to the 1,2,4-oxadiazole heterocycle. These compounds selectively inhibit GSK-3beta kinase with IC(50) value of 0.35 and 0.41 microM, respectively.

Synthesis and Anti-tumor Activities of Novel Methylthio-, Sulfinyl-, and Sulfonyl-8H-thieno[2,3-b]pyrrolizin-8-oximino Derivatives

A series of novel methylthio-, sulfinyl-, and sulfonyl-8H-thieno[2,3-b]pyrrolizin-8-oximino derivatives 7A-12P was designed and synthesized as anti-tumor agents. Their structures were confirmed by IR, (1)H-NMR, MS, and elemental analysis. The anti-tumor activities of all the target compounds were tested by the MTT method in vitro against Bel-7402 (human liver cancer) and HT-1080 (human fibro sarcoma) cell lines. Among them, compound 11N (IC(50) = 18.2 microM, 8.2 microM), was the most promising compound of all synthesized molecules, it was 2.5- and 3.3-times more active than cisplatin (IC(50) = 45.2 microM, 26.7 microM), respectively.