Detection of mucin 7 gene expression in exfoliated cells in urine from patients with bladder tumor.
OBJECTIVE
To determine whether mucin (MUC) 7 gene expression can be used as a bladder tumor marker for transitional cell carcinoma in patients with bladder carcinoma.


METHODS
Cells from the urine of 65 patients with bladder cancer, 15 patients with a negative bladder biopsy for bladder cancer, and 30 healthy volunteers were compared for the following parameters: tumor stage, grade, size, and number, urinary cytology, and expression of MUC7. Nested reverse transcriptase-polymerase chain reaction (RT-PCR) was used to determine MUC7 expression (348 base pairs).


RESULTS
MUC7 in the urine samples of the control group was negative (no false-positive results, specificity 100%). Among the 15 patients with nonmalignant disease, MUC7 was negative in 13 (specificity 87%). In the 2 patients with positive MUC7, the histologic examination showed chronic inflammation. Among the 65 patients with bladder transitional cell carcinoma, MUC7 was positive in 44 (68%). Nested RT-PCR for MUC7 was positive in 25 (61%) of 41 with superficial stages (pTa and pT1) versus 16 (76%) of 21 patients with Stage pT2 or advanced stages. Nested RT-PCR for MUC7 was positive in 5 (42%) of 12 patients with grade 1 disease, 22 (65%) of 34 patients with grade 2 disease, and 17 (89%) of 19 patients with grade 3 disease. We demonstrated no correlation between MUC7 and the clinicopathologic features (tumor stage, grade, or size) of urinary bladder tumors.


CONCLUSIONS
Our results indicate that MUC7 is a potential marker for bladder cancer. This noninvasive detection method assesses urothelial cells from voided urine specimens using RT-PCR.
Okegawa
Takatsugu
T
Department of Urology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
Kinjo
Manami
M
Horie
Shigeo
S
Nutahara
Kikuo
K
Higashihara
Eiji
E
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics; D001706:Biopsy; D002295:Carcinoma, Transitional Cell / Q000175:diagnosis / Q000235:genetics / Q000473:pathology / Q000652:urine*; D015179:Colorectal Neoplasms / Q000737:chemistry / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000032:analysis* / Q000235:genetics; D009363:Neoplasm Proteins / Q000032:analysis* / Q000235:genetics; D014411:Neoplastic Stem Cells / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012471:Salivary Proteins and Peptides; D014407:Tumor Cells, Cultured / Q000737:chemistry; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000473:pathology / Q000652:urine*; D014556:Urine / Q000166:cytology*
D014408:Biomarkers, Tumor; C083238:MUC7 protein, human; D009077:Mucins; D009363:Neoplasm Proteins; D012471:Salivary Proteins and Peptides