Sensitisation of Ehrlich ascitic tumour cells to methotrexate by inhibiting glutaminase.
BACKGROUND
Glutaminase activity is correlated with cancer proliferation and with growth rate in normal cells. Ehrlich ascites tumour cells (EATC) and their derivative 0.28AS-2 cells, which express antisense glutaminase mRNA, show differences in both morphology and tumorigenic capacity.


METHODS
Cell viability was determined with the microtetrazolium cytotoxicity test assay. Immunofluorescence staining with annexin-V and propidium iodide was carried out to assess the number of apoptotic cells.


RESULTS
0.28AS-2 cells are less resistant to H2O2 than EATC, since half the concentration of H2O2 caused a similar effect on the cell population in 24 h. Methotrexate significantly inhibited the proliferation of both EATC and 0.28AS-2 cells at concentrations higher than 64 nM after 48 h of exposure.


CONCLUSIONS
0.28AS-2 cells are highly sensitised to methotrexate. These results provide insights into the possible role of glutaminase in cancer therapy by demonstrating that the expression of antisense mRNA for glutaminase decreases chemoresistance to some pro-apoptotic agents.
Alonso
Francisco J
FJ
Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, 29071 Málaga, Spain.
Segura
Juan A
JA
Lora
Jorge
J
Lobo
Carolina
C
Fernández-Molina
Beatriz
B
Márquez
Javier
J
Matés
José M
JM
D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002286:Carcinoma, Ehrlich Tumor / Q000188:drug therapy* / Q000201:enzymology* / Q000473:pathology; D048708:Cell Growth Processes / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005972:Glutaminase / Q000037:antagonists & inhibitors* / Q000235:genetics; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008727:Methotrexate / Q000494:pharmacology*; D016372:RNA, Antisense / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics
D000964:Antimetabolites, Antineoplastic; D016372:RNA, Antisense; D012333:RNA, Messenger; D006861:Hydrogen Peroxide; D005972:Glutaminase; D008727:Methotrexate