Medulloblastoma is a cerebellar tumor and the most common pediatric brain malignancy. Radiotherapy is part of the standard care for this tumor, but its effectiveness is accompanied by significant neurocognitive sequelae due to the deleterious effects of radiation on the developing brain. We have previously shown that the protein kinase MRK/ZAK protects tumor cells from radiation-induced cell death by regulating cell-cycle arrest after ionizing radiation. Here, we show that siRNA-mediated MRK depletion sensitizes medulloblastoma primary cells to radiation. We have, therefore, designed and tested a specific small molecule inhibitor of MRK, M443, which binds to MRK in an irreversible fashion and inhibits its activity. We found that M443 strongly radiosensitizes UW228 medulloblastoma cells as well as UI226 patient-derived primary cells, whereas it does not affect the response to radiation of normal brain cells. M443 also inhibits radiation-induced activation of both p38 and Chk2, two proteins that act downstream of MRK and are involved in DNA damage-induced cell-cycle arrest. Importantly, in an animal model of medulloblastoma that employs orthotopic implantation of primary patient-derived UI226 cells in nude mice, M443 in combination with radiation achieved a synergistic increase in survival. We hypothesize that combining radiotherapy with M443 will allow us to lower the radiation dose while maintaining therapeutic efficacy, thereby minimizing radiation-induced side effects. Mol Cancer Ther; 15(8); 1799-808. ©2016 AACR.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1158/1535-7163.MCT-15-0849 | DOI Listing |
Mol Med Rep
March 2025
Department of Orthopedics, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing 100029, P.R. China.
Osteoarthritis (OA) is a common joint disorder involving the cartilage and other joint tissues. Quercetin (QCT) serves a protective role in the development of OA. However, to the best of our knowledge, the regulatory mechanisms of QCT in the progression of OA have not yet been fully elucidated.
View Article and Find Full Text PDFDrug Dev Res
February 2025
Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt.
Five series of new 1,3,4-thiadiazole hybrids were designed and synthesized as promising EGFR inhibitors. Three human cancer cell lines were employed for testing each hybrid's in vitro antiproliferative efficacy; colon HCT-116, liver HepG-2 and breast MCF-7 using MTT assay. Comparing compound 9a to the reference doxorubicin, 9a shown superior activity to that of Dox with respect to MCF-7 (IC 3.
View Article and Find Full Text PDFDrug Dev Res
February 2025
Pharmaceutical Medicinal Chemistry and Drug Design Department, Faculty of Pharmacy (Boys), Al-Azhar University, Nasr City, Cairo, Egypt.
New phthalazine-derived inhibitors for VEGFR-2 were synthesized for anticancer evaluations. Also, docking studies were performed to explore the suggested binding orientations of the novel derivatives inside the binding site of VEGFR-2. The achieved biological data were extremely interrelated to that of docking study.
View Article and Find Full Text PDFJ Biochem Mol Toxicol
January 2025
Department of Pharmaceutical Chemistry, Division of Computer-Aided Drug Design, R. C. Patel Institute of Pharmaceutical Education and Research, Shirpur, Maharashtra, India.
A series of 2,4-disubstituted pyrimidine derivatives bearing 5-substituted-1,3,4 thidiazole were devised and synthesized based on the binding mode of the approved drug Osimertinib with the ATP competitive site of EGFR-L858R/T790M in order to increase selectivity towards double mutant EGFR and potent antitumor activity. Their cellular bioactivity and corresponding enzyme inhibition were studied, and it was revealed that several compounds had significant biological activity and selectivity when compared to the control compounds. One of the most promising compound 8, substantially suppressed the proliferation of H1975 cells and showed significant inhibition of double mutant EGFR-L858R/T790M TK with IC values of 0.
View Article and Find Full Text PDFJ Biochem Mol Toxicol
January 2025
Department of Translational Medicine, Clinical Research Centre, Skåne University Hospital, Lund University, Malmö, Sweden.
Berberine, an isoquinoline alkaloid derived from various medicinal plants, emerges as a potential therapeutic agent against diverse human diseases. It has particularly shown notable anticancer efficacy against breast, colorectal, lung, prostate, and liver cancer. Berberine results in inhibition of cancer cell proliferation, induction of apoptosis, and suppressing angiogenesis, positioning it as a versatile, multitargeted therapeutic tool against cancer.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!