Project description:Mice with colonic tumors (chemically induced by AOM/DSS) were treated with Nutlin or control vehicle solution to analyze p53 target gene expression in vivo.
Project description:The heat-shock protein 90 (HSP90) is a promising target in cancer therapy, but its inhibitors' clinical trial failures are partly due to a compensatory heat-shock response (HSR) mediated by heat-shock factor 1 (HSF1). We previously showed that wildtype p53 reduces HSR by repressing HSF1 via a p21-CDK4/6-MAPK-HSF1 axis. Here, we explore if simultaneous p53 activation or cell cycle inhibition can disrupt the HSF1-HSR axis and enhance HSP90 inhibitors' efficiency. mRNA sequencing was performed on HCT116 cells treated for 24 hours with DMSO, 50 nM Ganetespib, 1 µM RG-7388, or their combination. We found that the p53 activator Idasanutlin suppresses HSF1-HSR activity in HSP90 inhibitor-based therapies, synergistically reducing cell viability and accelerating cell death in p53-proficient colorectal cancer (CRC) cells and organoids. Combination therapy upregulates p53 pathways, apoptosis, and inflammation. In a CRC mouse model, dual HSF1-HSP90 inhibition represses tumor growth and alters immune cell composition. CDK4/6 inhibition under HSP90 inhibition mimics HSR repression in p53-proficient CRC cells. In p53-deficient CRC cells and p53-mutated organoids, combined HSP90 and CDK4/6 inhibition suppresses HSF1-HSR and reduces cancer growth, offering a p53-independent strategy for CRC treatment. In conclusion, we present new options to improve HSP90-based therapies for enhanced CRC treatment.
Project description:MOLM-13 acute myeloid leukemia cells were treated with 7 µM 5-Azacytidine (Cayman Chemical 11164), or 450 nM CB-5083 (Cayman Chemical 19311), or in combination, or 0.1% DMSO as control. Treatments were conducted for 48 hours.
Project description:Prenatal irradiation can cause neurodevelopmental defects which are characterized by a reduction in brain size (microcephaly). The underlying molecular mechanisms in humans have so far not been studied. Here, we leveraged human forebrain organoids as a model for human embryonic brain development to investigate time- and dose-dependent effects of radiation on organoid growth. For this, organoids of 14 days and 56 days old were irradiated with acute X-ray doses of 0.5 Gy or 2 Gy and compared to controls. Using bulk RNA-seq at different early (6 h and 24 h) and late (14 days) time points after irradiation, we investigated mechanisms of radiation-induced growth defects which resulted from activation of the DNA damage response (cell cycle arrest, DNA repair, apoptosis), premature differentiation and the coordinated repression of primary microcephaly genes.
Project description:K562 cells with a CRISPR-engineered t(7;12)(q36;p13) translocation (K562-t(7;12)) and control line transiently transfected with Cas9 only (K562-ctrl) were FACS sorted on positivity to surface markers Kit and CD24.
Project description:Mice of the genetic background VBPN, VBPNA, VBPNC were injected with tamoxifen systemically (VBPN) or with 4-OHT intra-colonically (VBPNA, VBPNC). After tumor development, the material was processed and RNA-sequencing was conducted.
Project description:In the present study, Marchantia polymorpha Mppcs loss of function mutants were generated through CRISPR/cas9 mediated genome-editing. To assess whether the knockout of MpPCS gene affects the transcription of M. polymorpha nuclear genes in unstressed condition, the Mppcs-2 knockout mutant and Cam2 wild-type transcriptomes were compared by RNA-Seq.
Project description:LLC-OVA lung carcinoma cells were used to establish subcutaneous tumors in C57BL/6J mice. One million LLC-OVA cells were injected subcutaneously into each mouse. Tumor-bearing mice were divided into two treatment groups: three mice received mifepristone (60 mg/kg body weight) administered via oral gavage on alternate days, and four mice received vehicle control (olive oil) on the same schedule. Treatments were continued for 18 days. On day 19, mice were sacrificed and tumors were harvested for immune profiling. Tumor-infiltrating NK cells were isolated and subjected to bulk RNA-sequencing to assess transcriptional changes induced by glucocorticoid receptor antagonism within the tumor microenvironment.