Altered p-STAT3 (tyr705) expression is associated with histological grading and intratumour microvessel density in hepatocellular carcinoma.
BACKGROUND
Constitutive activation of signal transducer and activator of transcription 3 at tyrosine residue 705 (p-STAT3 (tyr705)) has been associated with many types of human cancers. However, its potential roles and biological effects in hepatocellular carcinoma (HCC) are not well established.


OBJECTIVE
To explore whether an altered p-STAT3 (tyr705) expression is associated with angiogenesis or proliferation and thereby plays a part in HCC development.


METHODS
Paraffin-wax-embedded sections from 69 patients with HCC were collected in this study. Using a semiquantitative immunohistochemical staining method, the expression patterns of p-STAT3 (tyr705) in both HCC lesions and the adjacent non-tumorous liver parenchyma were analysed. The results obtained were further correlated with intratumour microvessel density (MVD), Ki-67 expression, clinicopathological parameters and overall survival.


RESULTS
A strong p-STAT3 (tyr705) nuclear staining was observed in 49.3% of HCC lesions, but was reported only in 5.8% of the adjacent non-tumorous liver parenchyma (p<0.001). The expression of p-STAT3 (tyr705) in HCC lesions was significantly and positively correlated with the intratumour MVD (p = 0.002), but not with Ki-67 expression. No significant correlation of p-STAT3 (tyr705) was found in addition to histological grading (p = 0.019). Multivariate Cox regression analysis showed that p-STAT3 (tyr705) expression was a significant predictor of overall survival for HCC (p = 0.036), although the Kaplan-Meier survival curves showed no significant difference between the high and low p-STAT3 (tyr705) expression subgroups.


CONCLUSIONS
The results showed that p-STAT3 (tyr705) expression was closely correlated with histological grading and intratumour MVD in HCC. Thus, the potential role of p-STAT3 (tyr705) in HCC development may be through these correlations.
Yang
Sheau-Fang
SF
Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
Wang
Shen-Nien
SN
Wu
Chih-Fung
CF
Yeh
Yao-Tsung
YT
Chai
Chee-Yin
CY
Chunag
Shih-Chang
SC
Sheen
Maw-Chang
MC
Lee
King-Teh
KT
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism; D008113:Liver Neoplasms / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic / Q000378:metabolism* / Q000473:pathology; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D016019:Survival Analysis
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D050796:STAT3 Transcription Factor