[Co-expression of CD99/MIC2 and ALK in anaplastic large-cell lymphoma tissues and its significance].
OBJECTIVE
To investigate co-expression of CD99/MIC2 and anaplastic lymphoma kinase (ALK) protein in anaplastic large-cell lymphoma (ALCL) tissues and Karpas 299 cells and its significance.


METHODS
Clinical prognoses and ALK protein expressions of 25 cases of ALCL were reviewed retrospectively, the median duration of survival was analyzed for patients with ALK(+) ALCL and ALK(-) ALCL. Histological and immunohistochemical staining were applied to other 25 cases of ALCL and paraffin-embedded tissue from human anaplastic large-cell lymphoma Karpas 299 cells to detect the protein of CD99 and ALK.


RESULTS
Of former 25 cases of ALCL, median duration of survival for ALK(+) patients was 59 months, whereas 20 months for ALK(-) patients. The prognosis of ALK(+) group was better than that of ALK(-) group, survival curves of these two groups showed statistically significant (P < 0.05). CD99 was positive in 18 cases (72.0%) while negative in 7 cases (28.0%) of the latter 25 ALCL, ALK was positive in 19 cases (76.0%) while negative in 6 cases (24.0%); Of 19 ALK(+) ALCL, 16 (84.2%) cases co-expressed CD99-ALK; and in 6 ALK(-) ALCL, 2(33.3%) were CD99-ALK double negative, the expression of CD99 protein strongly correlated with that of ALK protein (P < 0.05). ALK and CD99 protein expressed in Karpas 299 cells with diffuse distribution.


CONCLUSIONS
CD99 highly expressed in ALCL, and showed high rate of co-expression with ALK. CD99 protein expression could be considered as a helpful diagnostic and prognostic factor of ALCL, especially for ALK(+) ALCL.
Department of Pathology, Southern Medical University, Guangzhou, China.
Lin
L
Zhong
Qing-zhu
QZ
Wei
Xue-ping
XP
Huang
Tian-hai
TH
Ji
Feng
F
Li
Zhi-qiang
ZQ
Wang
Xiang-zhao
XZ
Li
Jiang-huan
JH
Liu
Tong
T
Zhao
D000071443:12E7 Antigen; D000293:Adolescent; D000328:Adult; D000368:Aged; D000077548:Anaplastic Lymphoma Kinase; D015703:Antigens, CD / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D017728:Lymphoma, Large-Cell, Anaplastic / Q000175:diagnosis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D012189:Retrospective Studies; D055815:Young Adult
D000071443:12E7 Antigen; D015703:Antigens, CD; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases