Cross-resistance to five glucocorticoids in childhood acute lymphoblastic and non-lymphoblastic leukemia samples tested by the MTT assay: preliminary report.
In vitro antileukemic activity of five glucocorticoids and their cross-resistance pattern in childhood acute lymphoblastic and non-lymphoblastic leukemia were determined by means of the MTT assay in 25 leukemia cell samples of childhood acute leukemias. The equivalent antileukemic concentrations of the drugs tested were: 34 microM hydrocortisone (HC), 8 microM prednisolone (PRE), 1.5 microM methylprednisolone (MPR), 0.44 microM dexamethasone (DX) and 0.22 microM betamethasone (BET). In comparison with initial ALL cell samples, the relapsed ALL group was more resistant to PRE (38-fold, p = 0.044), DX (> 34-fold, p = 0.04), MPR (38-fold), BET (45-fold) and HC (33-fold). The AML cell samples were even more resistant to: PRE (> 85-fold, p = 0.001), DX (> 34-fold, p = 0.004), MPR (> 69-fold, p = 0.036), BET (> 69-fold, p = 0.038) and HC (54-fold, p = 0.059) when compared with ALL on initial diagnosis. A significant cross-resistance among all the glucocorticoids used was found. Only in some individual cases the cross-resistance was less pronounced.
Department of Pediatric Hematology and Oncology, Medical University, Bydgoszcz, Poland. jan_styczynski@kki.net.pl
Jan
J
Styczyński
Mariusz
M
Wysocki
Robert
R
Debski
Walentyna
W
Balwierz
Roma
R
Rokicka-Milewska
Michał
M
Matysiak
Anna
A
Balcerska
Jerzy
J
Kowalczyk
Jacek
J
Wachowiak
Danuta
D
Sońta-Jakimczyk
Alicja
A
Chybicka
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D019008:Drug Resistance, Neoplasm; D005260:Female; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D007223:Infant; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy*; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*; D013778:Tetrazolium Salts; D013844:Thiazoles
D005938:Glucocorticoids; D013778:Tetrazolium Salts; D013844:Thiazoles; C022616:thiazolyl blue