n-(cyanomethyl)-4-(2-((4-(4-morpholinyl)phenyl)amino)-4-pyrimidinyl)benzamide and Glioblastoma

Recent studies have showed that IKBKE is overexpressed in several kinds of cancers and that IKBKE-knockdown inhibits tumor progression. In this article, we first verified that two glioblastoma cell lines, U87-MG and LN-229, were sensitive to CYT387 by measuring the half maximal inhibitory concentration (IC50) with a CCK-8 assay and then demonstrated that CYT387, as a potent IKBKE inhibitor, suppressed glioblastoma cell proliferation, migration and invasion. Additionally, CYT387 induced cell apoptosis and arrested the cell cycle at the G2/M checkpoint in vitro. Furthermore, we showed that CYT387 did not simply inhibit IKBKE activity but also decreased IKBKE expression at the protein level rather than at the mRNA level. We discovered that CYT387 restrained malignant tumor progression by activating the Hippo pathway in vitro. By coimmunoprecipitation (co-IP), we showed that IKBKE interacted with TEAD2 and YAP1, thus accelerating TEAD2 and YAP1 transport into the nucleus. In subsequent in vivo experiments, we found that CYT387 inhibited subcutaneous nude mouse tumor growth but had little impact on intracranial orthotopic xenografts, probably due to a limited ability to penetrate the blood-brain barrier (BBB). These results suggest that CYT387 has potential as a new antiglioblastoma drug, but an approach to allow passage through the blood-brain barrier (BBB) is needed.

Topics: Animals; Benzamides; Cell Line, Tumor; Cell Proliferation; Glioblastoma; Hippo Signaling Pathway; Humans; I-kappa B Kinase; Mice; Protein Serine-Threonine Kinases; Pyrimidines

Temozolomide (TMZ) is a widely used chemotherapeutic agent for glioblastoma multiforme (GBM). However, chemoresistance to TMZ is still a major obstacle for GBM patients. An abundance of candidates has been reported to improve the chemotherapeutic sensitization of TMZ. In the present study, it was demonstrated that momelotinib (MTB) enhanced the sensitivity of glioma cells to TMZ in vitro, as evidenced by a noticeable decrease in cell growth and a significant increase in apoptosis and autophagy following treatment with the combination of TMZ and MTB compared to TMZ alone. Mechanistically, MTB and TMZ combination treatment reduced U251 cell growth by activating both apoptosis and autophagy pathways. MTB potentiated TMZ to inhibit the phosphorylation of JAK2 and STAT3 in U251 cells, resulting in the inactivation of JAK2/STAT3 signaling pathways. Moreover, we investigated the effect of MTB in xenograft tumor model mice. MTB and TMZ combination reduced tumor weight, decreased the expression of Ki‑67, P62, p‑STAT3 and p‑JAK2, while increased the ratio of LC3‑II/I and the expression of caspase‑3 and Beclin1 in vivo. Importantly, this combination was well tolerated, and caused significant tumor growth inhibition in the GBM xenografts. In summary, the present study provides pharmacological evidence that MTB has potential value in the treatment of GBM.

Topics: Adult; Animals; Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Autophagy; Benzamides; Brain Neoplasms; Cell Line, Tumor; Drug Resistance, Neoplasm; Drug Synergism; Glioblastoma; Humans; Janus Kinase 2; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Protein Kinase Inhibitors; Pyrimidines; Signal Transduction; STAT3 Transcription Factor; Temozolomide; Xenograft Model Antitumor Assays