Author/Editor		Trinkaus, Miha; Vranič, Andrej; Dolenc, Vincenc V; Lah, Tamara T
Title		Cathepsin L in human maningiomas
Translated title		Katepsin L pri meningiomu
Type		članek
Source		Radiol Oncol
Vol. and No.		Letnik 37, št. 2
Publication year		2003
Volume		str. 89-99
Language		eng
Abstract		Background. Although meningiomas are considered as benign tumours, about 10% comprise a subgroup of atypical meningiomas, classified as WHO grade II, with greater likelihood of recurrences and/or aggressive behaviour, including the possibility of brain tissue invasion. The lysosomal cysteine endopeptidase cathepsin L plays a role in tumour cell invasion and malignant progression of cancer, and has been suggested as a prognostic marker for certain types of tumours. Results. In our study, we compared the expression of cathepsin L in 30 meningiomas with their clinical invasiveness. Cathepsin L was determined by immunohistochemical analysis, quantitative real-time RT-PCR and Northern blot. We showed that expression of cathepsin L protein was significantly higher (p=0.019) in 9 atypical than in 21 benign meningiomas. Within the group of benign meningiomas, expression of cathepsin L was significantly lower in the transitional histological subtype. We measured the levels of cathepsin LA type of RNA splicing variants: LA, LAI and LAII, but not LAIII and not the LB variant, the letter being several times lower than the LA type. In contrast to protein levels, the levels of cathepsin LA, AI AII RNA variants did not differ between histological subtypes or between benign and typical meningiomas. The expression of total measured cathepsin LA, AI, AII RNA variants in the samples, taken from the centre and the periphery of the tumours, also showed no statistically significant differences. Conclusions. These results indicate that cathepsin L protein over-expression may contribute to the development of the agressive and possibly invasive character of atypical meningiomas and that it may be up regulated at the translational level.
Summary		lzhodišča. Čeprav so meningiomi benigni tumorji, jih okoli 10% sodi v skupino atipičnih meningiomov, klasificiranih kot WHO stopnja II, ki imajo večjo verjetnost recidiva in/ali bolj agresivno obnašanje, vključno z večjo verjetnostjo metastaziranja v možganovino. Lizosomalna cisteinska endopeptidaza katepsin L igra določeno vlogo v invaziji tumorskih celic in v malignem napredovanju raka in je prognostičen faktor za izid. Rezultati. V tem delu smo primerjali izražanje katepsina L v 30 meningiomih z njihovo klinično invazivnostjo. Za določevanje katepsina L smo uporabljali imunohistokemijsko reakcijo, kvantitativno RT-PCR analizo in hibridizacijo Northern. Ugotovili smo, da obstajajo značilne razlike v vsebnosti proteina katepsina L (p=0.019) med 9 atipičnimi in 21 benignimi meningiomi. Vsebnosti katepsina L v prehodnem tipu so bile nižje kot v ostalih vrstah benignih meningiomov. Merili smo tudi vsebnosti RNA cepitvenih različic katepsina L A vrst: LA, LAI in LAII, ne pa tudi LAIII in ne LB različice, ki je v meningiomih nekajkrat nižja kot so L A,AI, AII različice. V nasprotju s proteinsko koncentracijo, se skupne vsebnosti merjenih RNA različic katepsina L A, AI, AII med benignimi in atipičnimi meningiomi niso razlikovale. Ko smo primerjali skupne vsebnosti RNA katepsina L A različic med vzorci, vzetimi iz sredice in tistimi z roba tumorja, se te tudi niso statistično značilno razlikovale. Zaključki. Ti rezultati nakazujejo, da utegne povišana proteinska vsebnost katepsina L prispevati k razvoju agresivnosti in morebitne invazivnosti atipičnih meningiomov in da se njegovo izražanje verjetno poviša na nivoju prevoda RNA v protein.
Descriptors		MENINGIOMA CATHEPSINS NEOPLASM INVASIVENESS IMMUNOHISTOCHEMISTRY POLYMERASE CHAIN REACTION NEOPLASM STAGING BLOTTING, NORTHERN