TY - JOUR
T1 - Role of phosphatidylinositol 3′-kinase/AKT pathway in diffuse large B-cell lymphoma survival
AU - Uddin, Shahab
AU - Hussain, Azhar R.
AU - Siraj, Abdul K.
AU - Manogaran, Pulicat S.
AU - Al-Jomah, Naif A.
AU - Moorji, Azadali
AU - Atizado, Valerie
AU - Al-Dayel, Fouad
AU - Belgaumi, Asim
AU - El-Solh, Hassan
AU - Ezzat, Adnan
AU - Bavi, Prashant
AU - Al-Kuraya, Khawla S.
PY - 2006/12/15
Y1 - 2006/12/15
N2 - Phosphatidylinositol 3′-kinase (PI3K) is a key player in cell-growth signaling in a number of lymphoid malignancies, but its role in diffuse large B-cell lymphoma (DLBCL) has not been fully elucidated. Therefore, we investigated the role of the PI3K/AKT pathway in a panel of 5 DLBCL cell lines and 100 clinical samples. Inhibition of PI3K by a specific inhibitor, LY294002, induced apoptosis in SUDHL4, SUDHL5, and SUDHL10 (LY-sensitive) cells, whereas SUDHL8 and OCI-LY19 (LY-resistant) cells were refractory to LY294002-induced apoptosis. AKT was phosphorylated in 5 of 5 DLBCL cell lines and inhibition of PI3K caused dephosphorylation/inactivation of constitutively active AKT, FOXO transcription factor, and GSK3 in LY-sensitive cell lines. In addition, there was a decrease in the expression level of inhibitory apoptotic protein, XIAP, in the DLBCL cell lines sensitive to LY294002 after treatment. However, no effect was observed in XIAP protein levels in the resistant DLBCL cell lines following LY294002 treatment. Finally, using immunohistochemistry, p-AKT was detected in 52% of DLBCL tumors tested. Furthermore, in univariate analysis, high p-AKT expression was associated with short survival. In multivariate analysis, this correlation was no longer significant. Altogether, these results suggest that the PI3K/AKT pathway may be a potential target for therapeutic intervention in DLBCL.
AB - Phosphatidylinositol 3′-kinase (PI3K) is a key player in cell-growth signaling in a number of lymphoid malignancies, but its role in diffuse large B-cell lymphoma (DLBCL) has not been fully elucidated. Therefore, we investigated the role of the PI3K/AKT pathway in a panel of 5 DLBCL cell lines and 100 clinical samples. Inhibition of PI3K by a specific inhibitor, LY294002, induced apoptosis in SUDHL4, SUDHL5, and SUDHL10 (LY-sensitive) cells, whereas SUDHL8 and OCI-LY19 (LY-resistant) cells were refractory to LY294002-induced apoptosis. AKT was phosphorylated in 5 of 5 DLBCL cell lines and inhibition of PI3K caused dephosphorylation/inactivation of constitutively active AKT, FOXO transcription factor, and GSK3 in LY-sensitive cell lines. In addition, there was a decrease in the expression level of inhibitory apoptotic protein, XIAP, in the DLBCL cell lines sensitive to LY294002 after treatment. However, no effect was observed in XIAP protein levels in the resistant DLBCL cell lines following LY294002 treatment. Finally, using immunohistochemistry, p-AKT was detected in 52% of DLBCL tumors tested. Furthermore, in univariate analysis, high p-AKT expression was associated with short survival. In multivariate analysis, this correlation was no longer significant. Altogether, these results suggest that the PI3K/AKT pathway may be a potential target for therapeutic intervention in DLBCL.
UR - http://www.scopus.com/inward/record.url?scp=33845501828&partnerID=8YFLogxK
U2 - 10.1182/blood-2006-04-016907
DO - 10.1182/blood-2006-04-016907
M3 - Article
C2 - 16946303
AN - SCOPUS:33845501828
SN - 0006-4971
VL - 108
SP - 4178
EP - 4186
JO - Blood
JF - Blood
IS - 13
ER -