HSP60 may predict good pathological response to neoadjuvant chemoradiotherapy in bladder cancer.
BACKGROUND
Heat shock proteins (HSPs) play crucial roles in cellular responses to stressful conditions. Expression of HSPs in invasive or high-risk superficial bladder cancer was investigated to identify whether HSPs predict pathological response to neoadjuvant chemoradiotherapy (CRT).


METHODS
Immunohistochemistry was used to assess expression levels of HSP27, HSP60, HSP70, HSP90 and p53 in 54 patients with invasive or high-risk superficial bladder cancer, prior to low-dose neoadjuvant CRT, followed by radical or partial cystectomy. Patients were classified into two groups (good or poor responders) depending on pathological response to CRT, which was defined as the proportion of morphological therapeutic changes in surgical specimens. Good responders showed morphological therapeutic changes in two-thirds or more of tumor tissues. In contrast, poor responders showed changes in less than two-thirds of tumor tissues.


RESULTS
Using a multivariate analysis, positive HSP60 expression prior to CRT was found to be marginally associated with good pathological response to CRT (P = 0.0564). None of clinicopathological factors was associated with HSP60 expression level. In the good pathological responders, the 5-year cause-specific survival was 88%, which was significantly better than survival in the poor responders (51%) (P = 0.0373).


CONCLUSIONS
Positive HSP60 expression prior to CRT may predict good pathological response to low-dose neoadjuvant CRT in invasive or high-risk superficial bladder cancer.
Urushibara
Masayasu
M
Department of Urology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
Kageyama
Yukio
Y
Akashi
Takumi
T
Otsuka
Yukihiro
Y
Takizawa
Touichiro
T
Koike
Morio
M
Kihara
Kazunori
K
D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D015415:Biomarkers; D001706:Biopsy; D018834:Chaperonin 60 / Q000378:metabolism*; D005260:Female; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D012189:Retrospective Studies; D016019:Survival Analysis; D001749:Urinary Bladder Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology / Q000628:therapy
D000970:Antineoplastic Agents; D015415:Biomarkers; D018834:Chaperonin 60; D006360:Heat-Shock Proteins