[Clinical significance of regulatory T cells proportion in the peripheral blood and tumor tissue in primary hepatocellular carcinoma].

OBJECTIVE: To investigate the clinical significance of the amount of regulatory T cells (Treg) in the peripheral blood CD4+ cells and tumor tissue in primary hepatocellular carcinoma (HCC). METHODS: From January 1999 to December 2000, 63 HCC patients underwent radical resection in Sun Yatsen University Cancer Center. Tregs in those patients were detected in the samples of preoperative peripheral blood by flow cytometry and also in tissue samples of the resected tumors by immunohistochemistry. All patients had been followed up till Dec 30, 2005. The correlations of Treg amount in the peripheral blood CD4+ cells and tumor tissue with clinicopathologic characteristics and prognosis of HCC were analyzed. RESULTS: The proportion of Treg/CD4+ in the peripheral blood was significantly higher in the patients with HCC than that in those with HBsAg positive (P < 0.01) and in the normal controls (P < 0.01). The mean number of Treg in tumor tissue was (15.69 +/- 13.29)/mm2, but none or very few Treg was detected in the normal liver tissue, para-cancerous liver tissue, and HBV-infected liver tissue. The proportion of Treg/ CD4+ in the peripheral blood was significantly positively correlated with the number of Treg in tumor tissue (P = 0.024). The 5-year survival in patients with high amount of Treg in both peripheral blood and tumor tissue was significantly poorer than that in the patients with low amount of Treg (P = 0.042, 0.019). The 5-year disease-free survival rate was significantly lower in the patients with high amount of Treg in tumor tissue than that in the patients with lower amount (P = 0.001). CONCLUSION: Regulatory T cells in the circulatory blood and tumor tissue are increased in patients with hepatocellular carcinoma. The increased amount of regulatory T cells either in peripheral blood or in the tumor tissue is pertaining to poor prognosis. Detection of regulatory T cells both in the preoperative peripheral blood CD4+ cells and tumor tissue may be used as a potential immunological prognostic indicator for the hepatocellular carcinoma patients after radical resection.

Enhancing the efficiency of Epstein-Barr viral serologic test in the diagnosis of nasopharyngeal carcinoma.

OBJECTIVE: To investigate the efficiency of concurrent application of VCA-IgA, EA-IgA and EA-IgG serological tests in diagnosing nasopharyngeal carcinoma (NPC). METHODS: The sera of 266 untreated NPC patients and 347 healthy adults were collected. In addition to the conventional immunoenzymatic method of VCA-IgA test, enzyme-linked immunosorbent assay (ELISA) was adopted as an alternative to test the antibody level of EA-IgG and EA-IgA. A new statistical formula was used to evaluate the odds ratio of different combinations of these three tests. RESULTS: The sensitivity and specificity of VCA-IgA, EA-IgG and EA-IgA concurrently were as high as 95.11% and 97.41%, respectively, which were higher than those of single test (90.60% and 94.52% for VCA-IgA, 93.98% and 93.66% for EA-IgG, 89.84% and 88.18% for EA-IgA). Furthermore, the odds ratio of 3-test positivity (1 912.5) was higher than those of 2-test positivity (27.903 2 for VCA-IgA and EA-IgG, 11.169 0 for EA-IgG and EA-IgA, 8.032 8 for VCA-IgA and EA-IgA), which were even higher than those of 1-test positivity (0.121 4 for VCA-IgA, 0.170 5 for EA-IgG and 0.048 8 for EA-IgA). CONCLUSION: ELISA is more accurate in reflecting the antibody level of EA-IgG and EA-IgA than the conventional immunoenzymatic method. The concurrent application of VCA-IgA, EA-IgG and EA-IgA test can markedly improve the sensitivity, specificity and odds ratio as well, thus resulting in enhancing the efficiency of diagnosing nasopharyngeal carcinoma serologically.

[Micrometastasis distribution in liver tissue surrounding hepatocellular carcinoma].

OBJECTIVE: To study the micrometastasis distribution in liver tissue surrounding hepatocellular carcinoma (HCC), and provide reference for appropriate surgical safety margin. METHODS: Thirty-six patients with HCC but without clinical metastasis underwent hepatectomy. Their specimens showing ample surgical margin were made into giant sections. Tumor micrometastasis in liver tissue around the primary tumor were examined microscopically. In each specimen, the surrounding tissue was divided into proximal(p) and distal(d) areas. In either area, three lines of demarcation 0.5 cm, 1.0 cm, and 2.0 cm away from the margin of the primary tumor were designated as L(0.5), L(1.0) and L(2.0). Therefore, the surrounding tissue was divided into six zones - Z(p0.5), Z(p1.0), Z(p2.0) and Z(d0.5), Z(d1.0), Z(d2.0). The maximum micrometastasis spread distance (MMSD) and density (D(p0.5), D(p1.0), D(p2.0) and D(d0.5), D(d1.0), D(d2.0)) in each zone were analyzed after search for micrometastasis in the giant sections. RESULTS: 72.5% (111/153) micrometastases were found in form of microscopic tumor emboli. Their spread distance could be up to 6.1 cm. In 66.7% (24/36) specimens, micrometastases were found in the surrounding tissue. In 91.7% (22/24) of them, the distal MMSD was less than 3 cm. The proximal MMSD was less than 1.5 cm in 92.3% (12/13). The comparison of micrometastasis density in the different zones were D(d0.5) > D(d1.0) > D(d 2.0); D(p0.5) > D(p1.0) > D(p2.0); D(d1.0) > D(p1.0); D(d2.0) > D(p2.0) with significant differences. CONCLUSION: (1) Micrometastases of HCC exist mainly in form of microscopic tumor emboli, (2) The longer the distance from the primary focus, the lower the micrometastasis incidence, (3) In zones more than 0.5 cm away from the primary focus, tumor micrometastasis incidence is significantly lower in the proximal zones than that in the distal zones and (4) For HCC patients without clinical metastasis, a surgical margin of 3 cm wide in the distal area and 1.5 cm wide in the proximal area may reduce the rate of postoperative recurrence.

[Value of EBNA1-IgA and EA-IgG in serological diagnosis of nasopharyngeal carcinoma].

OBJECTIVE: To evaluate the value of EBNA1-IgA and EA-IgG in serological diagnosis of nasopharyngeal carcinoma (NPC). METHODS: The serum EBNA1-IgA and EA-IgG of 56 patients with NPC and 58 healthy adults were detected by ELISA. The sensitivity, specificity, positive predictive value, accuracy rate and odds ratio of the two tests used singly or in combination were compared with each other. RESULTS: The sensitivity of EBNA1-IgA (91.07%) was higher than that of EA-IgG (87.50%), while the specificity of EA-IgG (87.93%) was higher than that of EBNA1-IgA (84.48%). The combination of EBNA1-IgA and EA-IgG could enhance the specificity (94.83%), positive predictive value (0.9375), likelihood ratio (15.5435) and odds ratio (75.0000) for serological diagnosis of NPC. Forty-five patients showed both positive EBNA1-IgA and positive EA-IgG. A positive EA-IgG was detected in 4 out of 5 patients with negative EBNA1-IgA and a positive EBNA1-IgA was founded in 6 out of 7 patients with negative EA-IgG. CONCLUSION: Although relatively high sensitivity and specificity could be obtained by either EBNA1-IgA or EA-IgG test alone, the combination of these two tests with a complementary effect is able to enhance the reliability of serological diagnosis of NPC as most patients have positive ENBA1-IgA and EA-IgG concurrently.

Therapeutic targeting of the endothelin a receptor in human nasopharyngeal carcinoma.

The endothelin A receptor (ET(A)R) autocrine pathway is overexpressed in many malignancies, including nasopharyngeal carcinoma (NPC). In this tumor, ET(A)R expression is an independent determinant of survival and a robust independent predictor of distant metastasis. To evaluate whether ET(A)R represents a new target in NPC treatment, we tested the therapeutic role of ET(A)R in NPC. Cell proliferation was inhibited by the ET(A)R-selective antagonist ABT-627 in two ET(A)R-positive NPC cells in a dose-dependent manner. Proliferation of ET(A)R-negative NPC cells was not decreased. ET(A)R blockade also resulted in sensitization to cisplatin and 5-fluorouracil-induced apoptosis. In nude mice, ABT-627 inhibited the growth of NPC cell xenografts. Combined treatment of ABT-627 with the cytotoxic drug cisplatin or 5-fluorouracil produced additive antitumor effects. The antitumor activity of ABT-627 was demonstrated finally on an experimental lung metastasis by a reduction in the number of tumors. These results support the rationale of combining ABT-627 with current standard chemotherapy to further improve the therapeutic ratio in the treatment of NPC.

Elevated plasma big ET-1 is associated with distant failure in patients with advanced-stage nasopharyngeal carcinoma.

BACKGROUND: Endothelin-1 (ET-1) is a potent vasoactive peptide and a hypoxia-inducible angiogenic growth factor associated with the development and spread of solid tumors. The clinical significance of plasma big ET-1 in patients with advanced-stage nasopharyngeal carcinoma (NPC) is not known. METHODS: Pretreatment plasma big ET-1 levels were measured in 62 patients with advanced-stage NPC using a sandwich enzyme-linked immunoassay and compared with the levels from a control group (n = 19 participants). RESULTS: The median pretreatment plasma big ET-1 level in patients with advanced-stage NPC was 4.6 pg/mL (range, 1.9-15.2 pg/mL) and was significantly elevated compared with median plasma big ET-1 levels in healthy controls, 2.6 pg/mL (1.6-4.5 pg/mL) (P < .001). Using the upper limit (4.5 pg/mL) of control subjects as the cut-off value, plasma big ET-1 was < or = 4.5 pg/mL in 29 (46.8%) patients and > 4.5 pg/mL in 33 (53.2%) patients. A pretreatment plasma big ET-1 level > 4.5 pg/mL was associated with a significantly poorer 2-year distant metastasis-free survival rate (56.7% vs. 81.1%, P = .031). Multivariate analysis showed that N classification (hazard ratio [HR], 2.416; 95% confidence interval [CI], 1.071-5.447; P = .034) and pretreatment plasma big ET-1 level (HR, 3.151; 95% CI, 1.099-9.028, P = .033) were independent significant prognostic factors for posttreatment distant failure in patients with advanced-stage NPC. CONCLUSIONS: Pretreatment plasma big ET-1 levels may be useful in predicting posttreatment distant failure in patients with advanced-stage NPC.

[Expression of P53 and PCNA in nasopharyngeal carcinoma and their relation with clinical stage, VCA/IgA, EA/IgA, radiation sensibility, and pognosis].

BACKGROUND & OBJECTIVE: P53 and proliferating cell nuclear antigen(PCNA) relate with tumorigenesis, development, and prognosis of malignant tumors. This study was to detect expression of P53 and PCNA in nasopharyngeal carcinoma (NPC) tissue, and discuss their relation of p53 and PCNA expression with clinical stage, VCA/IgA, EA/IgA, radiation sensibility, and prognosis. METHODS: Immunohistochemistry was used to detect P53 and PCNA expression in NPC tissue of 80 patients received radiotherapy alone. Relation of P53 and PCNA expression with clinical stage, VCA/IgA, EA/IgA, extinction of nasopharygeal tumor and neck lymph node when radiation dose was 36 Gy, and 5-year survival rate was analyzed by Chi-square test. RESULTS: Positive rate of P53 in NPC tissues was 92.5%, and that of PCNA was 100%. Expression intensity of PCNA significantly related with extinction of nasopharygeal tumor, and neck lymph node when radiation dose was 36 Gy, but P53 had no significant relation with it. Expression intensities of P53 and PCNA had no significant relation with NPC clinical stage, VCA/IgA, EA/IgA, and 5-year survival rate. CONCLUSIONS: P53 and PCNA relate with NPC occurrence. PCNA relates with NPC radiation sensibility, but P53 doesn't. P53 and PCNA have no relation with NPC clinical stage, VCA/IgA, EA/IgA, and prognosis.

[Screening of dominant epitopes of antigens related to antibodies in the sera of patients with nasopharyngeal carcinoma].

BACKGROUND & OBJECTIVE: Epstein-Barr virus (EBV) is closely related to nasopharyngeal carcinoma (NPC). Many kinds of methods can be used to examine antibodies in NPC patients sera. This study was to screen the dominant epitopes from random peptide libraries (RPLs) displayed on phage using the EBV-related antibodies purified from the sera of NPC patients, and find new antigens at the epitope level. METHODS: The EBV-related antibodies were eluted from the sera of NPC patients using B95-8 cell EBV proteins as antigen, and the phages from 12-mer RPLs were elutriated for 3 rounds with the antibodies. The positive clones were gained by sandwich ELISA, and competitive inhibition assay from the third elution. The positive clones were sequenced, and the peptide coded by the inserted DNA were blasted with the antigen region of EBV proteins. RESULTS: Sixty-four phage clones were randomly picked up from the third eluate,25 positive clones were picked up using sandwich ELISA assay, the positive percentage was 39.06%. Thirteen clones were picked up for competitive ELISA assay,11 clones showed inhibitory phenomena,the inhibitory rates were between 18.09% and 65.94%. Five positive clones with high absorbency value, and high inhibitory rates were selected out, the sequences of peptides displayed on these clones were -A-T-S-H-L-H-V-R-L-P-W-T- (d15, and d18), -G-S-T-H-K-H-N-H-F-N-K-T- (d19), -K-P-I-H-E-H-P-H-R-F-K-S- (e8), -H-T-H-K-I-K-I-P-L-P-I-Q- (e23). These peptide sequences showed similarity with the amino acid sequences located in antigen regions of EBV integral membrane protein (d15, and d18), EBV thymidine kinase (d19), and EBV major capsid protein (e8, and e23). CONCLUSION: EBV-related epitopes could be obtained by screening the phages from RPLs with polyclonal antibodies purified from the sera of NPC patients, which may offer new methods of antigen preparation for sera diagnosis of NPC.