[The frequency of API2-MALT1 fusion gene variants in MALT lymphoma and its correlation with apoptosis of MALT lymphoma].
OBJECTIVE
To investigate the frequency of different variant of API2-MALT1 fusion gene in extranodal marginal zone B-cell lymphoma of mucosa-associated tissue(MALT1) lymphoma and the correlation between API2-MALT1 transcript and apoptosis of MALT lymphoma.


METHODS
The API2-MALT1 fusion transcripts were detected in 62 cases of MALT lymphoma by reverse transcription-polymeras chain reaction(RT-PCR) and Nested PCR. Five cases with reactive proliferation of lymph node were in use for negative control, and beta-actin was regarded as internal control; the apoptosis index, mRNA and protein of API2 were assayed in all samples by means of TUNEL, RT-PCR and immunohistochemistry respectively.


RESULTS
API2-MALT1 transcript was detected in 28 of 62 cases with MALT lymphoma (45.16%). Two kinds of API2-MALT1 variants (A1446-M1123 and A1446-M814) were detected. Variant A1446-M1123 was detected more frequently as compared with A1446-M814. The frequency of API2-MALT1 transcript was lower in thyroid MALT lymphoma(1/12) but similar in pulmonary and gastrointestinal MALT lymphoma. In the group of API2-MALT1(+), the apoptosis index was higher and the API2 mRNA and protein were lower when compared against those in the group of API2MALT1(-). But no significant differences in the levels of apoptosis and API2 were observed between the group of A1446-M1123(+) and A1446-M814(+).


CONCLUSIONS
API2-MALT1 transcript displayed variable frequency in MALT lymphomas of different sites. A1446-M1123 was noted to be probably the main type of API2-MALT1 variant in MALT lymphoma of Chinese. API2-MALT1 transcript was confirmed to be associated with the levels of apoptosis and API2 of MALT lymphoma.
Yang
Wen-xiu
WX
Department of Pathology, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041 PR China.
Li
Gan-di
GD
Zhou
Qiao
Q
Liu
Wei-ping
WP
Chen
Ni
N
Gong
Jing
J
D017209:Apoptosis / Q000235:genetics*; D001483:Base Sequence; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007150:Immunohistochemistry; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
C415943:API2-MALT1 fusion protein, human; D015514:Oncogene Proteins, Fusion