Frequency and prognostic relevance of cancer testis antigen 45 expression in multiple myeloma.
OBJECTIVE
This study aims to analyze the expression of cancer testis antigen 45 (CT45) in normal tissues and in plasma cell disorders and to identify possible associations with clinical data and prognosis in multiple myeloma (MM) patients.


METHODS
Expression of CT45 was studied in 20 normal tissues (testis, placenta, skeletal muscle, bladder, lung, spleen, heart, brain and fetal brain, thymus, uterus, stomach, mammary gland, pancreas, prostate, small intestine, kidney, adrenal gland, spinal cord, colon, and one pool of 10 normal bone marrow samples) and bone marrow aspirates from 3 monoclonal gammopathies of undetermined significance, 5 solitary plasmacytomas, 61 newly diagnosed MM patients and MM cell line U266 by reverse transcriptase polymerase chain reaction.


RESULTS
CT45 was positive in 3 of 20 (15%) normal tissues tested: lung, brain (both fetal and adult), and spinal cord. Among monoclonal gammopathies, CT45 was positive in 2 of 5 (40%) solitary plasmacytomas bone marrow aspirates, 10 of 61 (16%) MM bone marrow aspirates, and in the U266 MM cell line.


CONCLUSIONS
We did not find associations between bone marrow histology and CT45 expression. However, we demonstrated for the first time that positive expression of CT45 was associated with poor prognostic (International Staging System) and poor outcomes in MM patients, meaning that CT45-positive cases presented seven times more chance of worse evolution than the negative ones.
Andrade
Valéria C C
VC
Discipline of Hematology and Hemotherapy, Universidade Federal de São Paulo, UNIFESP, São Paulo, Brazil.
Vettore
André L
AL
Regis Silva
Maria Regina
MR
Felix
Roberta S
RS
Almeida
Manuella S S
MS
de Carvalho
Fabrício
F
Zago
Marco Antonio
MA
Caballero
Otavia L
OL
Simpson
Andrew J
AJ
Colleoni
Gisele W B
GW
D000368:Aged; D000951:Antigens, Neoplasm / Q000097:blood* / Q000378:metabolism*; D001853:Bone Marrow / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011379:Prognosis; D012015:Reference Standards; D020133:Reverse Transcriptase Polymerase Chain Reaction
D000951:Antigens, Neoplasm; C502804:CT45A1 protein, human