Biomarker-based prognosis in hepatocellular carcinoma: validation and extension of the BALAD model.

BACKGROUND: The Japanese 'BALAD' model offers the first objective, biomarker-based, tool for assessment of prognosis in hepatocellular carcinoma, but relies on dichotomisation of the constituent data, has not been externally validated, and cannot be applied to the individual patients. METHODS: In this Japanese/UK collaboration, we replicated the original BALAD model on a UK cohort and then built a new model, BALAD-2, on the original raw Japanese data using variables in their continuous form. Regression analyses using flexible parametric models with fractional polynomials enabled fitting of appropriate baseline hazard functions and functional form of covariates. The resulting models were validated in the respective cohorts to measure the predictive performance. RESULTS: The key prognostic features were confirmed to be Bilirubin and Albumin together with the serological cancer biomarkers, AFP-L3, AFP, and DCP. With appropriate recalibration, the model offered clinically relevant discrimination of prognosis in both the Japanese and UK data sets and accurately predicted patient-level survival. CONCLUSIONS: The original BALAD model has been validated in an international setting. The refined BALAD-2 model permits estimation of patient-level survival in UK and Japanese cohorts.

Quantitative assessment of the risk of rabies entering Japan through the importation of dogs and cats from the USA.

Up to October 2004, dogs and cats imported into Japan were subjected to a quarantine regimen which consisted of vaccination and a 30- to 365-day waiting period in the country of origin and a 14-day quarantine period upon arrival in Japan. This regimen was replaced by a new one, consisting of vaccination, antibody level titration and a 180-day waiting period in the country of origin, in November 2004. To evaluate the effect of this policy change, a quantitative risk assessment was undertaken. The risk of rabies entering Japan through the importation of dogs and cats from the USA under the old - and new - regimens was quantitatively assessed and compared. Under the new regimen, rabies will enter Japan once every 4932 years (90% confidence interval 1812-13 412 years) through the importation of dogs and cats from the USA. Under the old regimen, rabies would enter Japan once every 70 years (39-205 years), 83 years (45-267 years) or 190 years (104-609 years) assuming that the animal departs the country of origin 30 days, 180 days or 365 days after vaccination, respectively. This indicates the policy change would reduce the risk by a factor of 1/25-1/70.

AFP-L3: a new generation of tumor marker for hepatocellular carcinoma.

BACKGROUND: Alpha-fetoprotein (AFP) from hepatocellular carcinoma (HCC) displays differential affinity to lectin Lens culinaris agglutinin (LCA) compared to that from chronic hepatitis/liver cirrhosis. According to their binding capability to LCA, total AFP can be separated into three different glycoforms, AFP-L1, AFP-L2, and AFP-L3. AFP-L1 is the non-LCA-bound fraction, which constitutes the major glycoform of AFP in serum of chronic hepatitis and liver cirrhosis. AFP-L3 is the LCA-bound fraction of AFP. It has been reported that malignant liver cells produce AFP-L3, even when HCC is at its early stages, and especially when the tumor mass is supplied by the hepatic artery. Clinical research has determined that AFP-L3 is a highly specific marker for HCC. The AFP-L3 can be detected in the serum of approximately 35% of the patients with small HCC (<2 cm). The AFP-L3-positive HCC has potential for rapid growth and early metastasis. Compared to imaging techniques, it has been shown to have 9-12 months of lead-time in early HCC recognition. Combined sensitivity of AFP-L3 for HCC is 56%, with a specificity of >95%. METHODS: Automated assay for measuring AFP-L3 has been developed and introduced in clinical use. The new automated method for measurement of ALP-L3 is based on liquid phase binding of the AFP-L3 glycoform with LCA and two specific monoclonal antibodies labeled with peroxidase and polysulfated tyrosine peptide, respectively. CONCLUSION: AFP-L3 is a new generation of tumor marker for HCC and yields useful information on HCC for clinical decision making.

Lens culinaris agglutinin-reactive alpha-fetoprotein, an alternative variant to alpha-fetoprotein in prenatal screening for Down's syndrome.

BACKGROUND: Three serum tests, alpha-fetoprotein (AFP), human chorionic gonadotrophin and unconjugated oestriol, are now widely used for screening for Down's syndrome. Lens culinaris agglutinin-reactive alpha-fetoprotein (AFP-L3) is a variant of alpha-fetoprotein with alpha1-->6 fucose appended to the reducing terminal N-acetylglucosamine. It is the most prominent AFP detected in the serum of patients with hepatocellular carcinoma. METHODS: We investigated microheterogeneities of the carbohydrate chain on AFP in fetal liver tissues, amniotic fluids and maternal sera obtained from pregnancies with Down's syndrome using lectin affinity electrophoresis with four lectins. The percentages of AFP-L3 in maternal sera from 22 Down's syndrome and 227 unaffected pregnancies were determined. RESULTS: Unlike the case with AFP concentration, the percentage of AFP-L3 in maternal serum and amniotic fluid was similar, and apparently not influenced by membrane permeability. Knowing the percentage of AFP-L3 in maternal serum was effective for discriminating between Down's syndrome-affected pregnancies and unaffected pregnancies. The percentage of AFP-L3 in maternal serum identified 55% of Down's syndrome cases with a 5% false-positive rate. CONCLUSIONS: AFP-L3 should be an effective replacement for AFP in prenatal Down's syndrome screening.

Paradoxical weight loss with extra energy expenditure at brown adipose tissue in adolescent patients with Duchenne muscular dystrophy.

We examined the energy expenditure in patients with Duchenne muscular dystrophy(DMD) to evaluate the cause of the paradoxical weight loss observed in large numbers of adolescent patients before any obvious impairment of their swallowing function. In the morning, resting energy expenditure (REE)/m(2) was almost the same as that in normal controls despite a reduction in fat-free mass (FFM); thus, REE/m(2)/FFM was significantly increased in patients (median, 21.2 kcal/m(2)/FFM kg; range, 17.7 to 44.2, P =.012). A thermographic examination in the morning showed an obvious elevation of the body surface temperature on the back. This phenomenon was consistent with a paradoxical fall in the low frequency (LF)/high frequency (HF) ratio at night analyzed using the inter-RR spectrum by 24-hour electrocardiogram, which indicated relative activation of the sympathetic nervous system. The urinary secretion of norepinephrine at night was also significantly greater in patients (median, 0.119 microg/kg/h; range, 0.061 to 0.219, P =.011). These results suggest that paradoxical activation of the sympathetic nervous system may accelerate the production of heat in brown adipose tissue (BAT) and increase the level of energy consumption in patients, and that adolescent DMD patients may require greater caloric intake than expected to maintain body weight, which is important to improve the prognosis of their respiratory function.

Clinical evaluation of lentil lectin-reactive alpha-fetoprotein-L3 in histology-proven hepatocellular carcinoma.

INTRODUCTION: Serum alpha-fetoprotein (AFP) is a useful marker of hepatocellular carcinoma (HCC), although the serum AFP concentration is also increased in patients with chronic liver diseases (CLD). The analysis of AFP glycoforms has been known to be of diagnostic value. We applied the lectin-affinity electrophoresis and antibody-affinity blotting techniques to HCC patients in Vietnam in order to better understand the role of lentil lectin-affinity AFP-L3 in the diagnosis and differential diagnosis of HCC, and its relationship with the biological characteristics of HCC. METHODS: Lens culinaris agglutinin-reactive AFP (AFP-L3) was measured in 65 patients with histologically proven HCC and 25 patients with CLD. All patients had serum AFP levels above 54 ng/mL. AFP-L3 levels were determined by lectin affinity electrophoresis coupled with antibody-affinity blotting. The diagnosis of HCC was confirmed histologically by ultrasound-guided biopsy. RESULTS: The mean value of AFP-L3 in the HCC patients was 49.6 +/- 21.6%, which was significantly higher (p<0.001) than that in the 25 CLD patients (10.7 +/- 4.3%). When the cutoff level for AFP-L3 was set at 15% (mean +/- SD), the sensitivity was 96.9%, the specificity 92.0% and the accuracy 95.5% in the 65 HCC patients. There was no clear correlation between serum AFP level and AFP-L3 percentage (r=0.16). There was no correlation between AFP-L3 and the maximum diameter of HCC nodules (r=0.05). However, the mean AFP-L3 value was higher in moderately or poorly differentiated HCC than in well differentiated tumors (p<0.001). CONCLUSIONS: AFP-L3 is potentially a clinically useful marker for the differentiation of increased AFP levels in hepatocellular carcinoma and chronic liver diseases. The AFP-L3 percentage is closely related to HCC differentiation. We consider the analysis of AFP-L3 a useful adjunct in the diagnosis of HCC.

Structural characteristics of the N-glycans of two isoforms of prostate-specific antigens purified from human seminal fluid.

Prostate-specific antigen (PSA) is a glycosylated chymotrypsin-like serine protease and is found mainly in prostatic tissue and seminal fluid. We purified two forms of PSA (PSA-A and PSA-B) from human seminal fluid with pI values of approx. 7.2 and approx. 6.9, respectively. To characterize the N-glycans of the two isoforms, the sugar chains were liberated by hydrazinolysis followed by N-acetylation, and derivatized with 2-aminobenzamide. Both PSA-A and PSA-B contained mono- and disialylated sugar chains, although PSA-B had a much higher content of the latter. After removal of sialic acid residues by sialidase digestion, mono- and biantennary N-glycans and three outer chain moieties (Galbeta1-4GlcNAcbeta1-, GlcNAcbeta1-, GalNAcbeta1-4GlcNAcbeta1-) were found in both samples. However, the ratios of each N-glycan were different. These results indicate that PSA-A and PSA-B differ not only in their sialic acid contents, but also in their outer chain features.

Alpha-fetoprotein microheterogeneity: a potential biochemical marker for Down's syndrome.

Our purpose was to examine the utility of analyzing alpha-fetoprotein (AFP) microheterogeneity assessed by lectin affinity in Down's syndrome (DS) screening. Maternal sera and amniotic fluids were collected from 18 women who were carrying DS fetuses and 70 unaffected pregnancies around 16 weeks of gestation. The percentages of AFP which reacted with Lens culinaris agglutinin (AFP-L2,3) were determined by lectin affinity electrophoresis. AFP-L2,3 levels were significantly increased (P<0.0001) in both maternal serum and amniotic fluid from DS-affected versus unaffected pregnancies. The fractional areas under the receiver operating characteristic curves were 0.835 and 0.700 (P=0.106) for AFP-L3 and AFP MoM (multiples of the median) in maternal serum. No correlation was found between AFP-L3 and AFP MoM in maternal serum (r=0.006). Our data suggest that the measurement of AFP-L3 in maternal serum is a potential biochemical marker for DS.

Total alpha-fetoprotein and Lens culinaris agglutinin-reactive alpha-fetoprotein in fetal chromosomal abnormalities.

OBJECTIVE: To examine the differences in multiples of the median (MoM) of total alpha-fetoprotein, and the proportion of Lens culinaris agglutinin reactive alpha-fetoprotein (% alpha-fetoprotein-L2 + L3) in the maternal serum and amniotic fluid of pregnant women whose fetuses were diagnosed with autosomal or sex chromosomal abnormalities. DESIGN: Prospective consecutive series. SETTING: University hospital. SAMPLE: Maternal sera and amniotic fluids from 46 pregnant women with trisomy 21 fetuses, 10 pregnant women with trisomy 18 fetuses, one pregnant woman with a trisomy 13 fetus, six pregnant women with fetal sex chromosomal abnormalities, and 100 pregnant women for whom the fetal karyotype was diagnosed as normal following a genetic amniocentesis. RESULTS: The proportion of alpha-fetoprotein-L2 + L3 in maternal serum for trisomy 21 (40.3%. P < 0.0001) and trisomy 18 (39.8%, P < 0.05) showed a significantly higher value compared with normal (32.6%). The proportion of alpha-fetoprotein-L2 + L3 in amniotic fluid was significantly higher (P < 0.0001) for trisomy 21 (46.6%) than for a normal karyotype (41.5%). Only for the trisomy 21 group was there a strong correlation in the % alpha-fetoprotein-L2 + L3 between maternal serum and amniotic fluid (r = 0.840, P < 0.0001). For all groups, there was no correlation between alpha-fetoprotein MoM and % alpha-fetoprotein-L2 + L3 in maternal serum and amniotic fluid. CONCLUSION: The proportion of alpha-fetoprotein-L2 + L3 in maternal serum is an appropriate choice for a trisomy 21 biochemical marker, and it is possible that combining alpha-fetoprotein-L2 + L3 analysis with assays of alpha-fetoprotein in maternal serum could further improve the sensitivity and specificity of multiple marker screening.

Multicenter prospective analysis of newly diagnosed hepatocellular carcinoma with respect to the percentage of Lens culinaris agglutinin-reactive alpha-fetoprotein.

BACKGROUND AND AIM: The Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3) has been reported to be a highly useful marker for hepatocellular carcinoma (HCC) compared with a conventional serum AFP concentration, which allows earlier detection of HCC compared with using other imaging modalities and predicting prognosis after therapy. A collaborative prospective study involving nine Japanese hospitals was conducted to analyze the relationships between the tumor characteristics of a HCC patient and the percentage of AFP-L3/AFP total at the initial detection. METHODS: Between 1 October 1996 and 30 September 1997, a total of 388 patients with newly diagnosed HCC were registered. RESULTS: The cut-off level of the percentage of AFP-L3 was altered from 15 to 10%. The AFP-L3-positive HCC patients demonstrated the characteristics of having an advanced tumor, such as the number of tumors, maximum diameter, tumor spread, portal vein invasion, tumor stage, and tumor classification. With the conventional cut-off level of 15% of the percentage of AFP-L3, the malignant characteristics were more definite than that of 10%. However, no significant differences of serum AFP concentration were observed for malignant characteristics such as maximum diameter and histopathological grading. CONCLUSION: Serum AFP concentration does not reveal a malignancy of HCC, however, the AFP-L3-positive HCC has biologically malignant characteristics, especially portal vein invasion and lower tumor classification, and is an advanced tumor regardless of small tumor size and lower serum AFP concentration. As AFP-L3 shows the tumor characteristics, its presence should be an important factor in the determination of therapy and prognosis of patients.

Usefulness of measurement of Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein as a marker of prognosis and recurrence of small hepatocellular carcinoma.

OBJECTIVE: Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3%) is a recently described marker of hepatocellular carcinoma (HCC), and its usefulness has been demonstrated in many studies. We evaluated the usefulness of serial measurement of AFP-L3% as a marker of prognosis and recurrence after treatment of small HCC. METHODS: AFP-L3% was measured before and after initial treatment in 60 patients with small HCC (maximum diameter < or = 2 cm). AFP-L3% was taken as the ratio of AFP-L3 to total AFP and multiplied by 100%, and levels > or = 10% were considered positive. Outcomes and recurrence were compared between patients AFP-L3%-negative after initial treatment (Group A, n = 43) and patients who were AFP-L3%-positive after initial treatment (Group B, n = 17). RESULTS: Before treatment, AFP-L3% was positive in 14 (23.3%) of the 60 patients. The cumulative survival rate of Group A was significantly longer (p = 0.0091) than that of Group B. The recurrence rate was significantly higher in Group B (p = 0.0104) than in Group A. When recurrence was limited to intrahepatic metastasis, the recurrence rate was significantly higher in Group B (p = 0.0064). However, the recurrence rate of multicentric occurrence did not differ significantly between Groups A and B. CONCLUSIONS: Measurement of AFP-L3% after treatment may be useful for understanding prognosis and recurrence of HCC.

Clinical utility of Lens culinaris agglutinin-reactive alpha-fetoprotein in small hepatocellular carcinoma: special reference to imaging diagnosis.

BACKGROUND/AIMS: Blood concentration levels of alpha-fetoprotein like the Lens culinaris agglutinin-reactive fraction (AFP-L3) are a useful marker for predicting the long-term prognosis of hepatocellular carcinoma. This study investigated the relationship between serum AFP-L3 and various imaging modalities. METHODS: Sixty-three patients with small hepatocellular carcinomas < or = 2 cm in diameter were studied. Serum AFP-L3 concentrations were measured by lectin-affinity electrophoresis coupled with antibody-affinity blotting and expressed as % AFP-L3 (the percent of AFP-L3 as total AFP). A clinical "cutoff level" of 10% was used in this study to indicate the presence of hepatocellular carcinoma. Selective hepatic intraarterial digital subtraction angiography (DSA), ultrasonographic angiography with carbon dioxide microbubbles (USAG), and computed tomography during arterial portography (CTAP) were performed to evaluate the hemodynamics of hepatic nodules. RESULTS: Fourteen (22.2%) of the 63 patients were positive for % AFP-L3. The % AFP-L3 levels (n=45, 4.4%) of patients with hypervascular tumors were significantly higher than those (n=15, 0.0%) of patients with isovascular or hypovascular tumors as determined by USAG (p=0.0061). The % AFP-L3 levels (n=53, 4.4%) of patients with a negative portal blood supply were significantly higher than the % AFP-L3 levels (n=7, 0.0%) of patients with a positive portal blood supply as determined by CTAP (p=0.0140). The % AFP-L3 levels of patients with tumors with a long doubling time (DT) were significantly lower than for patients with tumors with a short DT (p=0.0176). CONCLUSION: AFP-L3 is a positive indicator which may be more specific for small advanced hepatocellular carcinoma.

Evaluation of curability and prediction of prognosis after surgical treatment for hepatocellular carcinoma by lens culinaris agglutinin-reactive alpha-fetoprotein.

The clinical significance of serum lens culinaris agglutinin-reactive alpha-fetoprotein (AFP-L3), which can distinguish between hepatocellular carcinoma and hepatitis by detecting a sugar chain micro heterogeneity, was evaluated for its possible ability to recognize previously undetectable residual tumors, and for increasing the accuracy of prognosis after surgical treatment for hepatocellular carcinoma. Serum lens culinaris agglutinin-reactive alpha-fetoprotein was measured pre- and post-operatively in 130 patients who underwent curative surgical treatment for hepatocellular carcinoma. The preoperative AFP-L3 positive rate was 35.4%. AFP-L3 remained positive postoperatively in 28 of the 46 preoperative AFP-L3 positive patients, and converted to positive in 4 of the 84 preoperative AFP-L3 negative patients. Regardless to preoperative AFP-L3, the postoperative AFP-L3 positive patients had a poorer recurrence-free rate (p<0.0001). The postoperative L3 positive patients had a high incidence of recurrence due to metastasis, but did not have recurrence due to multicentric origin. Multivariate analysis revealed that AFP-L3 (p<0.0001) was the most independently significant factor for predicting survival after surgery among several conventional prognostic factors. Thus, AFP-L3 is a valuable marker for evaluation of curability of surgical treatment and for improving the accuracy of prognosis.

Lectin-dependent modulation of interaction between human alpha-fetoprotein and its monoclonal antibodies. Epitope mapping.

The effect of lentil lectin (LCA) on the binding of mouse monoclonal antibody (MoAb) against human alpha-fetoprotein (AFP) to LCA-nonreactive AFP-L1 and LCA-reactive AFP-L3 was studied on a panel of 30 MoAbs provided by the TD-2 Workshop of ISOBM for epitope mapping. LCA inhibited the binding of MoAbs 93 and 98 to AFP-L3 but not to AFP-L1, indicating that there was a competition between the MoAbs and LCA for the AFP sugar chain. With MoAbs 100, 109, 118, and 120, LCA rather increased the binding to AFP-L3 over that to AFP-L1. These modulating effects of LCA on the MoAb binding to AFP-L3 were abolished by periodate treatment of the AFP preparations without affecting the binding of MoAb to AFP. Concanavalin A had similar inhibiting and enhancing effects on MoAb binding, but equally to AFP-L1 and AFP-L3, both of which are fully reactive with concanavalin A. The results suggested that MoAbs 93 and 98 recognized epitopes closely related to sugar chain, and their binding to AFP-L3 was inhibited by the bound LCA due to steric hindrance. The enhanced binding of some MoAbs to AFP-L3 over AFP-L1 with LCA, or both glycoforms of AFP with concanavalin A, may be explained by postulating an allosteric mechanism mediated by the oligosaccharide-lectin interaction.

Determination of alpha-fetoprotein concentration based on liquid-phase binding assay using anion exchange chromatography and sulfated peptide introduced antibody.

A new immunoassay for alpha-fetoprotein based upon liquid-phase binding reactions is described. In this procedure, a sample that contains alpha-fetoprotein is mixed with a solution of two anti-alpha-fetoprotein monoclonal antibodies complexed with peroxidase and sulfated peptide, respectively. After incubation, immune complex is separated from other components by anion exchange column chromatography. Immune complex is quantified using fluorometric detection by peroxidase enzymatic activity. Peroxidase activity correlated with a alpha-fetoprotein with a 1:1 relationship. The stoichiometric immunoreaction allowed a large analytical range (0.4-7500 ng/ml) with a linear dose-response relationship, high sensitivity and good precision. Endogenous substances did not interfere with assay performance. Assay results showed good correlation with other established methods. These results indicate that the method is useful for clinical alpha-fetoprotein determinations.

Automatic and simultaneous analysis of Lens culinaris agglutinin-reactive alpha-fetoprotein ratio and total alpha-fetoprotein concentration.

An automated analytical method for analyzing alpha-fetoprotein (AFP) carbohydrate chain microheterogeneity based on competitive reaction between lectin and anti-AFP monoclonal antibody in liquid phase is described. The antibody used binds to all species of AFP molecule without Lens culinaris agglutinin (LCA); however, its binding reaction to LCA-reactive AFP was inhibited by LCA. Sulfated tyrosine octamer was conjugated to the antibody, and sulfated tyrosine pentamer and peroxidase were conjugated to other monoclonal antibodies, respectively. Serum reacted with three anti-AFP monoclonal antibodies and LCA in liquid phases, and two types of immune complex were observed. The two types were separated directly by the liquid-phase binding assay system equipped with an anion-exchange column. Peroxidase activity of immune complex was determined fluorophotometrically. Total AFP concentration and the ratio of LCA-reactive AFP in samples were calculated simultaneously, using the sum of the two peaks and the ratio of peaks obtained by LCA inhibition to sum of two peaks. The results correlated well with conventional methods. The method is simple and convenient for routine clinical assays.

Liquid-phase binding assay of alpha-fetoprotein using a sulfated antibody for bound/free separation.

A rapid immunoassay using a sulfated antibody for bound/free separation in a liquid-phase binding assay is described. A first anti-alpha-fetoprotein monoclonal antibody was labeled with peroxidase (Fab'-POD) and a second monoclonal antibody was conjugated with polysulfated tyrosine peptide (Fab'-YS). The monoclonal antibodies and alpha-fetoprotein (AFP) were mixed, incubated, and analyzed directly by anion-exchange column chromatography. The amount of POD activity in the column effluent was determined fluorophotometrically. The bound (Fab'-POD + AFP + Fab'-YS) and free (Fab'-POD) forms of the conjugate were clearly and easily separated by ionic charge, and the free sulfated antibody (Fab'-YS) was not detectable fluorophotometrically. The elution position of the bound conjugate was adjusted by varying the length of the polysulfated tyrosine peptide. This method is convenient for antigen measurement because (1) only two modified antibodies are used in a buffer solution, (2) the concentration of antibodies and other assay conditions are easily set, (3) no solid phase is required, and (4) no washing is necessary.

Prognostic significance of Lens culinaris agglutinin A-reactive alpha-fetoprotein in small hepatocellular carcinomas.

BACKGROUND & AIMS: Lens culinaris agglutinin A-reactive fraction of alpha-fetoprotein (AFP-L3) has been reported to be a useful marker in the early diagnosis of hepatocellular carcinoma (HCC). The aim of this study was to evaluate the prognostic value of AFP-L3 for HCC. METHODS: Fifty-five patients with HCC whose AFP-L3 levels were negative before initial therapy were studied. AFP-L3 levels were measured by lectin-affinity electrophoresis coupled with antibody-affinity blotting. RESULTS: Of the 55 patients, 28, 15, and 12 underwent percutaneous ethanol injection, transcatheter arterial embolization, and hepatectomy, respectively. Thirty-two (58.2%) of the 55 patients maintained a negative AFP-L3 status during the study, and 23 patients (41.8%) became positive for AFP-L3 during posttreatment observation. Multiple recurrences of HCC and portal vein tumor thrombus were observed significantly more often in patients with positive AFP-L3 than in those with negative AFP-L3 status (P < 0.0001). In contrast, most patients with negative AFP-L3 had solitary recurrences of HCC without portal vein tumor thrombus. Overall survival was significantly lower in patients with positive AFP-L3 than in those with negative AFP-L3 status (P = 0.0006). Cox's proportional hazards model identified that AFP-L3 was an independent prognostic factor (P = 0.0005). CONCLUSIONS: AFP-L3 seems to be a significant marker of poor prognosis for HCC.

Comparison of carbohydrate structures of serum alpha-fetoprotein by sequential glycosidase digestion and lectin affinity electrophoresis.

Serum alpha-fetoprotein (AFP) is a glycoprotein of which the sugar chain is considered to show structural changes with malignancies. Microheterogeneity of the serum AFP carbohydrate structure was studied in samples from 35 patients with benign and malignant diseases. Sera were digested directly, extensively, and sequentially with sialidase. beta-galactosidase and beta-N-acetylhexosaminidase. Before and after digestion, sera were examined by means of lectin affinity electrophoresis using eight lectins. Relationships between AFP carbohydrate structures and liver diseases were elucidated by the lectin-reactive profiles and the effect of glycosidase digestion. More than 94% of the AFP carbohydrate structures found in patients with benign and malignant liver diseases were biantennary complex-type oligosaccharides. Changes in the AFP carbohydrate structures at the early stage of hepatocellular carcinoma revealed the addition of alpha 1-->6 fucose to the reducing terminal N-acetylglucosamine and monosialylated AFPs. In both advanced hepatocellular carcinoma and AFP producing extrahepatic malignancies, AFP carbohydrate structures were characterized as the further addition of beta 1-->4 N-acetylglucosamine and heterogeneity in the galactose and N-acetylglucosamine residues. Sequential glycosidase digestion and lectin affinity electrophoresis is useful for analysing the carbohydrate structures of serum glycoprotein.

Monitoring of lectin-reactive alpha-fetoproteins in patients with hepatocellular carcinoma treated using transcatheter arterial embolization.

OBJECTIVE: To evaluate the value of lectin-reactive alpha-fetoprotein (LR-AFP) levels for assessing therapeutic effects and for predicting prognosis in patients with hepatocellular carcinoma (HCC) treated using transcatheter arterial embolization (TAE). DESIGN: Twenty-nine patients with HCC were studied. METHODS: LR-AFP levels were measured using lectin-affinity electrophoresis coupled with antibody-affinity blotting. Patients who were initially LR-AFP-positive were divided into those who became negative after TAE and those who remained positive. Patients were also classified into groups showing a reduction in total AFP levels of 75% or more and those showing a reduction of less than 75% and into groups whose tumour size was reduced by 50% or more and those whose tumour size was reduced by less than 50%. RESULTS: Both the length of time between TAE and the recurrence of HCC and the cumulative survival rate differed significantly between the group of patients who became negative after TAE and that which remained positive. However, no significant differences in these parameters were found between the patients in the two classes for total AFP levels or tumour size. CONCLUSIONS: LR-AFP levels appeared to be more useful for predicting clinical results than the serum total AFP value or changes in tumour size.