Gene-expression signature of adhesion/growth-regulatory tissue lectins (galectins) in transitional cell cancer and its prognostic relevance.
OBJECTIVE
Lectins, and especially galectins, appear to be important in malignancy-associated processes. The aim was to analyse comprehensively the presence of galectins in urothelial tumours.


RESULTS
Non-cross-reactive antibodies against seven family members from the three subgroups (prototype: galectin-1, -2 and -7; chimera type: galectin-3; tandem-repeat type: galectin-4, -8 and -9) were used. Gene expression was monitored in specimens of normal urothelium, fresh tumour tissue and cell lines by real-time polymerase chain reaction (PCR). The presence and evidence of tumour-associated up-regulation were shown for galectin-1 and -3. This was less clear-cut for galectin-4 and -8. Galectin-7 was expressed in all cell lines; galectin-2 and -9 were detected at comparatively low levels. Galectin-2, -3 and -8 up-regulation was observed in superficial tumours, but not in muscle-invasive tumours (P < 0.05). Immunoreactivity correlated with tumour grading for galectin-1, -2 and -8, and disease-dependent mortality correlated with galectin-2 and -8 expression. Binding sites were visualized using labelled galectins.


CONCLUSIONS
The results demonstrate a complex expression pattern of the galectin network in urothelial carcinomas. Galectin-1, -2, -3 and -8 are both potential disease markers and also possible targets for bladder cancer therapy.
Langbein
S
S
Department of Urology, Academic Medic Centrum, University of Amsterdam, Amsterdam, The Netherlands. s.i.langbein@amc.uva.nl
Brade
J
J
Badawi
J K
JK
Hatzinger
M
M
Kaltner
H
H
Lensch
M
M
Specht
K
K
André
S
S
Brinck
U
U
Alken
P
P
Gabius
H-J
HJ
D001665:Binding Sites; D002295:Carcinoma, Transitional Cell / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D016172:DNA Fingerprinting; D037161:Galectins / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D009367:Neoplasm Staging; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D019459:Urothelium / Q000473:pathology
D037161:Galectins