BACKGROUND.Early detection of hepatocellular carcinoma (HCC), one of the most common and deadly tumors worldwide, still is difficult due to the lack of adequate biomarkers that show high sensitivity and specificity. The authors recently demonstrated that squamous cell carcinoma antigen (SCCA) variants were overexpressed remarkably in all surgically resected HCCs. METHODS.For the current study, the authors assessed the presence of SCCA, as a free form and complexed with immunoglobulins, in serum from patients with HCC, cirrhosis, and chronic hepatitis and from healthy control participants and compared SCCA measurement with the measurement of ␣-fetoprotein (AFP) levels. RESULTS.Circulating immune complexes (ICs) composed by SCCA and immunoglobulin M (IgM) IC (SCCA-IgM IC) were undetectable (Ͻ 120 arbitrary units[AU]/mL) in serum from a healthy control population (0 of 73 controls); however, 35 of 50 patients with HCC (70%) were reactive for SCCA-IgM IC independent of etiology (mean Ϯ standard deviation [SD], 2568.5 Ϯ 6797.3 AU/mL). No correlation was found with AFP levels, which were elevated significantly in only 21 of 50 patients with HCC (42%). By using an AFP cut-off value of 20 ng/mL, 96% of patients with HCC were positive for at least 1 marker. Among cirrhotic patients, the presence of circulating SCCA-IgM IC was displayed in 13 of 50 patients (26%), but at lower levels compared with the patients who had HCC (mean Ϯ SD, 147.5 Ϯ 348.3 AU/mL; P Ͻ 0.01; Student t test), whereas 9 of 50 patients with chronic hepatitis (18%) were reactive (mean Ϯ SD, 39.5 Ϯ 89.7 AU/mL). No significant presence of free SCCA, free anti-SCCA variants IgG or IgM, or SCCA-IgG IC was found. CONCLUSIONS.The study results indicated that SCCA-IgM ICs represent novel serologic biomarkers, which, alone or in combination with AFP, can increase the sensitivity for diagnosing HCC significantly.

Pathogenetic mechanisms of hepatocellular carcinoma (HCC) are still unclear and new tools for diagnostic and therapeutic purposes are ongoing. We have assessed whether squamous cell carcinoma antigen (SCCA), a serpin overexpressed in neoplastic cells of epithelial origin, is also expressed in liver cancer. Squamous cell carcinoma antigen was evaluated by immunohistochemistry in 65 HCCs of different aetiology and in 20 normal livers. Proliferative activity was assessed using MIB-1 antibody. In 18 surgical samples, tumour and nontumour liver tissue was available for SCCA cDNA amplification and sequencing. Squamous cell carcinoma antigen was detected in 55 out of 65 (85%) tumour specimens, but in none of the 20 controls. In the majority of the cases, the positive signal was found in the cytoplasm of more than 50% of the hepatocytes. Low or undetectable SCCA (scorep1) was associated to lower MIB-1 labelling index, compared to cases with SCCA score X2 (mean7s.d.: 2%72.4 vs 7.5%710.3, Po0.05). Squamous cell carcinoma antigen mRNA could be directly sequenced in 14 out of 18 liver tumours but in none of the corresponding nontumour samples. From sequence alignment, a novel SCCA1 variant (G 351 to A) was identified in five cases, while SCCA1 was revealed in six cases and SCCA2 in three cases. In conclusion, SCCA variants are overexpressed in HCC, independently of tumour aetiology. A novel SCCA1 variant has been identified in one third of liver tumours. Hepatocellular carcinoma (HCC) is one of the most important sanitary problems over the world for its high prevalence and for its poor prognosis. More than 250 000 new cases per year are diagnosed and mean 5-year survival is lower than 5% (El-Serag and Mason, 1999). Several factors have been involved in the development of liver cancer, some of them differing in various geographic areas and explaining, at least in part, distinct geographical incidence (Bruix et al, 2001). The most powerful risk factor is the presence of liver cirrhosis. Among cirrhotic Caucasian patients, chronic viral infection by HBV and HCV are the most biologically relevant causes leading to this clinical condition (Benvegnù et al, 1994). However, pathogenetic mechanisms of neoplastic transformation are still unclear; several growth factors and tumour suppressor genes (Collier et al, 1993; Naka et al, 1998; Abou-Shady et al, 1999) have been involved but insufficient data have been generated to date. cDNA microarray analyses for gene expression profiling and potential identification of target genes for diagnostic or therapeutic purposes are ongoing (Shirota et al, 2001;Takeo et al, 2001;Xu et al, 2001).Squamous cell carcinoma antigen is a serine protease inhibitor physiologically found in the spinous and granular layers of normal squamous epithelium, but typically expressed by neoplastic cells of epithelial origin (Kato, 1996). Recent studies indicate that both SCCA1 and SCCA2, the two isoforms so far identified (Schneider et al, 1995), protect neoplastic cells from apoptotic death induced by several k...

About 3-4% of cirrhotic patients develop primary liver cancer every year. Specific serologic markers have not yet been identified for screening of high risk patients. The serpin squamous cell carcinoma antigen (SCCA) is overexpressed in liver cancer and circulating SCCA-IgM complexes have been described in patients with hepatocellular carcinoma (HCC). The aim of the present study was to assess the behavior of SCCA-IgM in relation to HCC development in patients with cirrhosis. A retrospective, longitudinal study was conducted in a cohort of prospectively followed cirrhotic patients. Two groups with similar clinical profile at presentation were studied : group A included 16 patients who developed HCC during a median follow up of 4 years; group B included 17 patients who did not develop HCC during the same time interval. Circulating SCCA-IgM immune complexes were determined using a recently standardized ELISA assay. At presentation similar levels of SCCA-IgM complexes [mean 6 SD: 267.40 6 382.25 U/ml vs. 249.10 6 446.90 U/ml, p 5 0.9006] and of alpha-fetoprotein [AFP; 24.11 6 59.04 IU/ml vs. 10.91 6 23.34 IU/ml, p 5 0.3995] were detected in group A and in group B. The increase over time (/) of SCCA-IgM, assessed within at least one year before clinical diagnosis of HCC, was remarkably higher in group A than in group B (mean 6 SD 5 280.05 6 606.71 (U/ml)/year vs. 237.92 6 95.94 (U/ml)/year, p 5 0.0408), while AFP increase was not significantly different (11.89 6 23.27 (IU/ml)/year vs. 3.67 6 11.46 (IU/ ml)/year, p 5 0.2179). Receiver operating characteristic (ROC) curves were plotted for the rate of change in the levels of both markers and the diagnostic accuracy measured as AUROC was higher for SCCA-IgM / (0.821) than for AFP / (0.654). In conclusion, the progressive increase of SCCA-IgM over time was associated with liver tumor development, suggesting that monitoring the behavior of SCCA-IgM might become useful to identify cirrhotic patients at higher risk of HCC development. ' 2006 Wiley-Liss, Inc.Key words: SCCA-IgM; hepatocellular carcinoma; serologic prognostic marker; cirrhosis Hepatocellular carcinoma (HCC) is one of the major health problems worldwide, due to its high incidence and severe prognosis. Figures depicting half a million new cases per year have been reported, and projection studies have estimated an increase of tumor development within the next decade in developed countries. 1The reasons advocated to explain this phenomenon are the increased rate of HCV infection and an improvement in clinical management of liver cirrhosis, identified as the major risk factor for HCC development.2 About 3-4% of cirrhotic patients develop primary liver cancer every year and this justifies surveillance programs to detect HCC at an early stage. 3 The prognosis of the patients depends mainly on the evolutionary stage of the neoplasm, ranging from 5-years survival higher than 70% in surgical patients to less than 3 months in very advanced tumors. 4 Tumor size is one of the main factors influencing the possibility of b...

We assessed the presence of alpha-fetoprotein (AFP) complexed with IgM (AFP-IgM IC) in serum of patients affected by hepatocellular carcinoma (HCC), cirrhosis and chronic hepatitis as well as in healthy subjects by means of a dedicated ELISA assay. The amount of AFP-IgM IC was expressed in arbitrary units (AU) on a reference standard curve. Free AFP (FAFP) levels were determined in parallel in each sample by means of an automated immunoassay system. The mean serum concentration of AFP-IgM IC was significantly higher in HCC patients (mean +/- SD: 1378.3 +/- 2935.7 AU/mL) than in cirrhotic patients (129.8 +/- 261.4 AU/mL) and in patients with chronic hepatitis (80.9 +/- 168.9 AU/mL) (p < 0.01). HCC patients had FAFP values above the 20 ng/mL cutoff in 44% of cases (22/50) and AFP-IgM IC values above the 120 AU/mL cutoff in 60% of cases (30/50). The occurrence of the free and IgM-complexed form of circulating AFP did not overlap, and 82% of patients (41/50) were positive for at least one marker. The results indicate that AFP-IgM IC is a complementary serological marker to FAFP and that the combination of these biomarkers may be useful in the diagnosis of liver cancer.

We have recently shown that alpha fetoprotein (AFP) and squamous cell carcinoma antigen (SCCA), biomarkers associated with hepatocellular carcinoma, may be detected in patient sera as circulating immune complexes with IgM, and that assessment of serum levels of AFP-IgM and SCCA-IgM may be used for the detection of liver cancer. In this study we measured the levels of carcinoembryonic antigen (CEA) as free form (FCEA) and complexed to IgMs (CEA-IgM) in sera of patients affected by colorectal carcinoma (CRC) at different stages as well as in healthy subjects. FCEA levels were above the 5 ng/mL cutoff in 43% of CRC patients (31/72) and CEA-IgM levels were above the 200 AU/mL cutoff in 38% of CRC patients (27/72). Serum levels of CEA-IgM immune complexes (IC) and FCEA did not overlap and 64% of patients (46/72) were positive for at least one marker without compromising the detection specificity (94%). Early detection of CRC was significantly improved by CEA-IgM IC assay. CRC patients at an early stage (stage 1) had elevated CEA-IgM levels in 29% of cases (7/24), while FCEA levels were elevated in only 8% of cases (2/24). These results indicate that CEA-IgM is a complementary serological marker to FCEA which is much more sensitive for early stage CRC, and that the combination of these biomarkers may be useful in the early detection of colorectal cancer.