Combined effects of p53, p21, and pRb expression in the progression of bladder transitional cell carcinoma.
OBJECTIVE
To determine the combined effects of p53, p21, and pRb alterations in predicting the progression of bladder transitional cell carcinoma.


METHODS
p53, p21, and pRb expression was examined immunohistochemically on archival radical cystectomy samples from 164 patients with invasive or high-grade recurrent superficial transitional cell carcinoma (TCC; lymph node-negative, 117 patients; lymph node-positive, 47 patients). Median follow-up was 8.6 years. Based on percentage of nuclear reactivity, p53 was considered as wild-type (0% to 10%) or altered (>10%); p21 was scored as wild-type (>10%) or altered (<10%); and pRb status was considered wild-type (1% to 50%) or altered (0% or >50%).


RESULTS
As individual determinants, the p53, p21, and pRb status were independent predictors of time to recurrence (P<.001, P<.001, and P<.001, respectively), and overall survival (P<.001, P=.002, and P=.001, respectively). By examining these determinants in combination, patients were categorized as group I (no alteration in any determinant, 47 patients), group II (any one determinant altered, 51 patients), group III (any two determinants altered, 42 patients), and group IV (all three determinants altered, 24 patients). The 5-year recurrence rates in these groups were 23%, 32%, 57%, and 93%, respectively (log-rank P<.001), and the 5-year survival rates were 70%, 58%, 33%, and 8%, respectively (log-rank P<.001). After stratifying by stage, the number of altered proteins remained significantly associated with time to recurrence and overall survival.


CONCLUSIONS
This study suggests that alterations in p53, p21, and pRb act in cooperative or synergistic ways to promote bladder cancer progression. Examining these determinants in combination provides additional information above the use of a single determinant alone.
Department of Pathology, University of Southern California Keck School of Medicine, 1441 Eastlake Ave, Los Angeles, CA 90033, USA.
Sunanda J
SJ
Chatterjee
Ram
R
Datar
David
D
Youssefzadeh
Ben
B
George
Peter J
PJ
Goebell
John P
JP
Stein
Lillian
L
Young
Shan-Rong
SR
Shi
Conway
C
Gee
Susan
S
Groshen
Donald G
DG
Skinner
Richard J
RJ
Cote
D002295:Carcinoma, Transitional Cell / Q000378:metabolism* / Q000473:pathology / Q000628:therapy; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000378:metabolism*; D018450:Disease Progression; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D011379:Prognosis; D016016:Proportional Hazards Models; D012008:Recurrence; D016160:Retinoblastoma Protein / Q000378:metabolism*; D016019:Survival Analysis; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000628:therapy
C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D016160:Retinoblastoma Protein; D016159:Tumor Suppressor Protein p53