The expression of HSP27 is associated with poor clinical outcome in intrahepatic cholangiocarcinoma

Antonello A Romani¹ , Pellegrino Crafa² , Silvia Desenzani¹ , Gallia Graiani² , Costanza Lagrasta² , Mario Sianesi³ , Paolo Soliani³ and Angelo F Borghetti¹

¹Dipartimento di Medicina Sperimentale – Sezione di Patologia Molecolare ed Immunologia, Università degli Studi di Parma, 43100 Parma, Italy

²Dipartimento di Patologia e Medicina di Laboratorio – Sezione di Anatomia ed Istologia Patologica, Università degli Studi di Parma, 43100 Parma, Italy

³Dipartimento di Scienze Chirurgiche – Sezione di Clinica Chirurgica Generale e dei Trapianti d'Organo, Università degli Studi di Parma, 43100 Parma, Italy

author email corresponding author email

BMC Cancer 2007, 7:232doi:10.1186/1471-2407-7-232


Published:	21 December 2007

Abstract

Background

The heat shock proteins (HSPs) 27-kDa (HSP27) and 72-kDa (HSP72), are ubiquitous chaperone molecules inducible in cells exposed to different stress conditions. Increased level of HSPs are reported in several human cancers, and found to be associated with the resistance to some anticancer treatments and poor prognosis. However, there is no study of the relationship between HSPs expression and patient's prognosis in intrahepatic cholangiocarcinoma (IHCCA). In this exploratory retrospective study, we investigated the expressions of HSP27 and HSP72 as potential prognostic factors in IHCCA.

Methods

Thirty-one paraffin-embedded samples were analyzed by immunohistochemical methods using HSP27 and HSP72 monoclonal antibodies. Proliferation rate was assessed in the same specimens by using monoclonal antibody against phosphorylated histone H3 (pHH3). Fisher's exact test was used to assess the hypothesis of independence between categorical variables in 2 × 2 tables. The ANOVA procedure was used to evaluate the association between ordinal and categorical variables. Estimates of the survival probability were calculated using the Kaplan-Meier method, and the log rank test was employed to test the null hypothesis of equality in overall survival among groups. The hazard ratio associated with HSP27 and HSP72 expression was estimated by Cox hazard-proportional regression.

Results

The expression of HSP27 was related to mitotic index, tumor greatest dimension, capsular and vascular invasion while the expression of HSP72 was only related to the presence of necrosis and the lymphoid infiltration. Kaplan-Maier analysis suggested that the expression of HSP27 significantly worsened the patients' median overall survival (11 ± 3.18 vs 55 ± 4.1 months, P-value = 0.0003). Moreover HSP27-positive patients exhibited the worst mean survival (7.0 ± 3.2 months) in the absence of concomitant HSP72 expression.

Conclusion

The expression of HSP27, likely increasing cell proliferation, tumor mass, vascular and capsular invasion, might promote aggressive tumor behaviour in IHCCA and decrease patients' survival. Immunohistochemical detection of HSP27 on routine sections may provide a reliable prognostic marker for IHCCA able to influence the therapeutic strategies for this cancer.