Molecular Biology And Clinical Features Of Multiple Meningiomas

Objective:Meningiomas are the most common primary human intracranial tumors that account for 13-20 percentage of all central nerve system tumors. It arises from meningothelial cells. The apparent pathogenesis of meningioma is still unclear. In general, they are slow-growing tumors with benign behavior, but about 3 percent of meningiomas with malignant behavior. Along with the classification of the tumors of nervous system adopted by WHO, there are three types of meningiomas, benign (grade I) , atypical(grade II)and anaplastic (malignant) (grade III). Benign meningiomas grow slowly, have integrated membrances covering, may be cured by excision and have good curative effect, but part of them may be recurred in clinic. At the same time, malignant meningiomas have fast-growing and recurrent after operation. Meningiomas can be divided into solitary meningiomas(SMs) and multiple meningiomas(MMs). Multiple meningiomas account for 40 percent of all intracranial tumors. They are different in shape, size and occurring site, therefore, they have different influence , clinic features and symptoms. When diagnosis they are needed to distinguish with metastasis meningiomas and recrudescent meningiomas. The apparent pathogenesis of multiple meningiomas is still unclear. In order to instruct its clinical diagnosis and therapy, more researches are need to do.At present, there are two mechanisms involved in carcinogenesis: one is genetic alterations with changes in DNA sequence and epigenetic alterations without changes in DNA sequence. Genetic alterations include mutation, chromatin deletion and rearrangement, etc. Another is epigenetic alterations. It mainly refers to the methylation of DNA 5'-flanking region, and it can result in aberrant expression of...