MicroRNA-10b (miR-10b) is commonly elevated in glioblastoma (GBM), while not expressed in normal brain tissues. Targeted inhibition of miR-10b has pleiotropic effects on GBM derived cell lines, it reduces GBM growth in animal models, but does not affect normal neurons and astrocytes. This data raises the possibility of developing miR-10b-targeting GBM therapy. However, the mechanisms contributing to miR-10b-mediated glioma cell survival and proliferation are unexplored. We found that inhibition of miR-10b has distinct effects on specific glioma cell lines. In cells expressing high levels of tumor suppressor p21WAF1/Cip1, it represses E2F1-mediated transcription, leading to down-regulation of multiple E2F1 target genes encoding for S-phase specific proteins, epigenetic modulators, and miRNAs (e.g. miR-15/16), and thereby stalling progression through the S-phase of cell cycle. Subsequently, miR-15/16 activities are reduced and many of their direct targets are de-repressed, including ubiquitin ligase FBXW7 that destabilizes Cyclin E. Conversely, GBM cells expressing low p21 level, or after p21 knock-down, exhibit weaker or no E2F1 response to miR-10b inhibition. Comparative analysis of The Cancer Genome Atlas revealed a strong correlation between miR-10b and multiple E2F target genes in GBM and low-grade glioma. Taken together, these findings indicate that miR-10b regulates E2F1-mediated transcription in GBM, in a p21-dependent fashion.
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http://dx.doi.org/10.18632/oncotarget.3009 | DOI Listing |
Exp Hematol Oncol
January 2025
Department of Medical Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China.
Background: Osimertinib has emerged as a critical element in the treatment landscape following recent clinical trials. Further investigation into the mechanisms driving resistance to Osimertinib is necessary to address the restricted treatment options and survival advantages that are compromised by resistance in patients with EGFR-mutated lung adenocarcinoma (LUAD).
Methods: Spatial transcriptomic and proteomic analyses were utilized to investigate the mechanisms of Osimertinib resistance.
Int J Mol Sci
December 2024
Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda 669-1330, Hyogo, Japan.
In almost all cancers, the p53 pathway is disabled and cancer cells survive. Hence, it is crucially important to induce cell death independent of p53 in the treatment of cancers. The transcription factor E2F1 is controlled by binding of the tumor suppressor pRB, and induces apoptosis by activating the gene, an upstream activator of p53, when deregulated from pRB by loss of pRB function.
View Article and Find Full Text PDFCell Death Discov
December 2024
High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, China.
Ribonucleotide reductase M1 (RRM1), the catalytic subunit of ribonucleotide reductase, plays a pivotal role in converting ribonucleotides (NTP) into deoxyribonucleotides (dNTP), essential for DNA replication and repair. Elevated RRM1 expression is associated with various human cancers, correlating with poorer prognosis and reduced overall survival rates. Our previous study found that RRM1 will enter the nucleus to promote DNA damage repair.
View Article and Find Full Text PDFFront Pharmacol
July 2024
Division of Abdominal Tumor Multimodality Treatment, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
Long noncoding RNAs (lncRNAs) constitute a distinctive subset of RNA molecules with limited protein-coding potential, which exert crucial impacts on various biological activities. In the context of cancer, dysregulated lncRNAs function as essential regulators that affect tumor initiation and malignant progression. These lncRNAs serve as competitive endogenous RNAs (ceRNAs) through sponging microRNAs and regulating the expression of targeted genes.
View Article and Find Full Text PDFBr J Cancer
August 2024
School of Pharmacy, Jiangsu University, Zhenjiang, 212013, Jiangsu, China.
Background: Poly (ADP-ribose) polymerase inhibitors (PARPis) can effectively treat ovarian cancer patients with defective homologous recombination (HR). Loss or dysfunction of PTEN, a typical tumour suppressor, impairs double-strand break (DSB) repair. Hence, we explored the possibility of inhibiting PTEN to induce HR deficiency (HRD) for PARPi application.
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