Expression of hypoxic marker carbonic anhydrase IX predicts poor prognosis in resectable hepatocellular carcinoma.

Carbonic anhydrase IX (CA-IX), a hypoxia marker, correlates with tumor progression in a variety of human cancers. However, the role of CA-IX in hepatocellular carcinomas (HCCs) remains largely unknown. We examined the expression of 277 unifocal, resectable, primary HCC tumors using immunohistochemistry. The CA-IX protein was expressed in 110 of the 227 (48.5%) HCC tumors. The expression of CA-IX correlated with younger age (P = 0.0446), female sex (P = 0.0049), high serum α-fetoprotein levels (P<1x10-6), larger tumor size (P = 0.0031), high tumor grade P<1x10-6) and high tumor stage (P = 1.5x10-6). Patients with HCC tumors that expressed CA-IX were more likely to have lower 5-year disease-free survival (DFS; P = 0.0001) and 5-year overall survival (OS; P<1x10-6). The multivariate analysis indicated that CA-IX expression was an independent predictor for high tumor stage (P = 0.0047) and DFS (P = 0.0456), and a borderline predictor for OS (P = 0.0762). Furthermore, CA-IX expression predicted poor DFS and OS in patients with high tumor stage (P = 0.0004 and P<1x10-6, respectively). Interestingly, CA-IX expression might contribute to the worse prognosis of female patients with advanced HCCs. Our study indicates the expression of the CA-IX protein is a crucial predictor of poor prognosis in resectable HCC, and it is also an unfavorable prognostic predictor in HCC patients with high tumor stage

Kaplan–Meier analyses of 5-year disease free survival (DFS) and 5-year overall survival (OS) in 227 patients with HCC.

<p>(A and B) The HCCs with CA-IX protein expression correlated with significantly lower DFS and OS than the HCCs without CA-IX protein expression (<i>P</i> = 0.0001 and <i>P</i><1x10^-6, respectively). (C and D) The combinatorial analyses revealed that CA-IX-positive high-stage HCCs had the lowest DFS (<i>P</i><1 x10^-6) and OF (<i>P</i><1x10^-6), which were lower than CA-IX negative high-stage HCCs (<i>P</i> = 0.0004 and <i>P</i><1x10^-6, respectively). However, there were no differences concerning both DFS and OS in low-stage HCCs regardless presence or absence of CA-IX expression. (E and F) The female patients presenting with high-stage HCCs exhibited the lowest DFS (<i>P</i><1 x 10^-6) and OS (<i>P</i><1x10^-6), which were lower than male patients presenting with high-stage HCCs (<i>P</i> = 0.0214 and <i>P</i> = 0.0188, respectively). However, there were no differences concerning DFS and OS in male and female patients with low-stage HCCs. (+): The presence of CA-IX protein expression. (-): The absence of CA-IX expression.</p

Univariate analysis of CA-IX protein expression with various clinical and pathological features in 227 patients with surgically resectable primary hepatocellular carcinoma.

<p>Univariate analysis of CA-IX protein expression with various clinical and pathological features in 227 patients with surgically resectable primary hepatocellular carcinoma.</p

Multivariate analyses of the risk factors associated with high stage tumor, disease-free survival and overall survival of patients with surgically resectable primary hepatocellular carcinoma.

<p>Abbreviations: S.E., Standard error; O.R., Odds ratio; H.R., Hazard ratio; C.I., Confidence interval; AFP, α-fetoprotein; L, Low or Large; H, High; S, Small; P, presence; N, absences.</p><p>^† Logistic regression model</p><p>^‡ Cox’s proportional hazards model</p><p>Multivariate analyses of the risk factors associated with high stage tumor, disease-free survival and overall survival of patients with surgically resectable primary hepatocellular carcinoma.</p

Expression of CA-IX protein in non-cancerous liver parenchyma and HCC.

<p>(A and C) Immunohistochemical staining showed heterogeneous and diffuse membranous/cytoplasmic expression of CA-IX in HCC. (E) In the region of tumor necrosis, the viable tumor cells surrounding the necrotic area (<i>N</i>) exhibited strong CA-IX expression. (B, D, F) B, D, and F were the nontumorous counterpart of A, C, and E, respectively. They exhibited strong staining in the bile duct epithelial cells in the portal area but not in the hepatocytes or the mesenchymal cells. A-F x200 (original magnification).</p

Analysis of CA-IX protein expression in 227 patients with surgically resectable primary hepatocellular carcinoma stratified by gender and tumor stage

<p>Abbreviations: H, high tumor stage; L, low tumor stage.</p><p>a, b, and c designate comparison between the indicated two groups.</p><p><i>P</i> values:</p><p>^a0.0275;</p><p>^b0.0385;</p><p>^c< 1x10^-6</p><p>Analysis of CA-IX protein expression in 227 patients with surgically resectable primary hepatocellular carcinoma stratified by gender and tumor stage</p