[Study on activation of AKT/mTOR pathway in anaplastic large cell lymphoma].
OBJECTIVE
To study the expression of anaplastic lymphoma kinase (ALK) and the phosphorylation status of AKT, mammalian target of rapamycin (mTOR), 4E-binding protein 1 (4E-BP1) and ribosomal protein S6 kinase (p70S6K) and their interrelationships and clinical pathological significance in anaplastic large cell lymphoma (ALCL) patients.


METHODS
Immunohistochemical and EnVision methods were used to detect the expression of ALK, p-AKT, p-mTOR, p-4E-BP1 and p-p70S6K.


RESULTS
Among the 81 ALCL patients, 51 (63.0%) expressed ALK, whereas the other 30 (37.0%) did not. Patients with ALK(+) ALCL had a better prognosis than those with ALK-ALCL (P < 0.05). Out of the 71 ALCL samples studied, p-AKT was detected in 54 (76.1%) samples and its phosphorylation was correlated with ALK expression (P < 0.05); p-mTOR was detected in 57 (80.3%) samples and its expression was correlated with both ALK and p-AKT (P < 0.05); p-4E-BP1 and p-p70S6K were detected in 64 (90.1%) and 66 (93.0%) samples respectively, and their expressions were related with p-mTOR (P < 0.05), but not with ALK or p-AKT (P > 0.05). COX Proportional Hazard Model analysis showed that both the expression of ALK and the B symptoms affected the prognosis (P < 0.05), moreover, the former had greater impact than the later.


CONCLUSIONS
Expressions of p-AKT, p-mTOR, p-4E-BP1 and p-p70S6K are detected in ALCL, while ALK(+) cases have higher incidence than those with ALK(-) cases. Phosphorylation of AKT and mTOR is correlated with ALK expression, suggesting that there is an activated pathway of AKT/mTOR in patients with ALK(+) ALCL, but the activation have no obvious prognostic significance.
Li
Jin-Fan
JF
Department of Pathology, West China Hospital, Sichuan University, Chengdu 610041, China.
Li
Gan-di
GD
Gu
Ling
L
Liu
Wei-Ping
WP
Li
Feng-Yuan
FY
Liao
Dian-Ying
DY
Ma
Zhi-Gui
ZG
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000368:Aged; D000077548:Anaplastic Lymphoma Kinase; D018797:Cell Cycle Proteins; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D017728:Lymphoma, Large-Cell, Anaplastic / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases; D055815:Young Adult
D048868:Adaptor Proteins, Signal Transducing; D018797:Cell Cycle Proteins; C087000:EIF4EBP1 protein, human; D047908:Intracellular Signaling Peptides and Proteins; D010750:Phosphoproteins; C546842:MTOR protein, human; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D058570:TOR Serine-Threonine Kinases