Related Experiment Video
Updated: May 30, 2026
05:10
Intracranial Orthotopic Allografting of Medulloblastoma Cells in Immunocompromised Mice
Published on: October 3, 2010
Genetic alterations in microRNAs in medulloblastomas
Sheng-Qing Lv1, Young-Ho Kim, Fiaschetti Giulio
1International Agency for Research on Cancer (IARC), Lyon, France Neuro-Oncology Program, University Children's Hospital of Zurich, Switzerland.
Brain Pathology (Zurich, Switzerland)
|July 29, 2011
Summary
Alterations in microRNA (miRNA) genes, particularly miR-512-2, are linked to MYCC overexpression in medulloblastomas. This suggests a novel mechanism driving tumor development, impacting MYCC regulation.
Area of Science:
- Oncology
- Genetics
- Molecular Biology
Background:
- MicroRNAs (miRNAs) are crucial regulators of cellular processes, often targeting multiple genes.
- MYCC is a proto-oncogene frequently implicated in medulloblastoma development.
- Understanding miRNA involvement in MYCC regulation offers insights into medulloblastoma pathogenesis.
Purpose of the Study:
- To investigate alterations in specific miRNA genes and their relationship with MYCC expression in medulloblastomas.
- To determine if miRNA gene alterations contribute to MYCC overexpression in this cancer type.
Main Methods:
- Screening of 48 medulloblastomas for mutations, deletions, and amplifications in nine selected miRNA genes.
- Differential PCR and real-time RT-PCR to detect genetic alterations and MYCC expression levels.
- Functional assays including antisense knockdown, overexpression, and luciferase reporter assays to confirm miRNA-target interactions.
Main Results:
- Significant deletions were observed in several miRNA genes, including miR-512-2 (33%).
- MYCC overexpression was detected in 30% of cases, correlating with miR-512-2 gene deletion.
- Functional studies confirmed that miR-512-2 directly targets and downregulates MYCC expression.
Conclusions:
- Genetic alterations in miRNA genes, especially miR-512-2, represent a mechanism for MYCC overexpression in medulloblastomas.
- These findings highlight the role of miRNAs as tumor suppressors in medulloblastoma by regulating MYCC.
- Targeting miRNA-dysregulation could offer new therapeutic strategies for medulloblastoma.
Related Concept Videos
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
01:22MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
01:20The Retinoblastoma Gene
Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
01:45Destabilization of Microtubules
The destabilization of microtubules can occur during different stages of the microtubule lifecycle, such as nucleation or elongation. It can take place at either end of the microtubule or in the microtubule lattices as a whole. The lifespan of individual microtubules within a cell varies according to the cell type and stage of the cell cycle. During interphase, the lifespan of the microtubule is about 30 minutes, while during cell division, it is about 15 minutes. In axonal microtubules of...
02:23Abnormal Proliferation
Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...