Regional differences of methylation of metallothionein-3 gene in tissues of esophageal cancer / 肿瘤

Objective:To investigate the methylation of CpG island of metallothionein-3 (MT-3) gene in esophageal cancer tissues and normal tissues in middle and south area of Hebei Province and Chaoshan area of Guangdong Province and compared the results with those in low risk area of esophageal cancer. Methods:The blood samples from 10 normal volunteers, 10 embryonic esophageal tissues, 20 esophageal mucosa tissues from normal subjects in low risk area as well as 30 fresh surgical specimens of esophageal cancer and 30 normal marginal tissues in the high risk middle-south Hebei Province and Chaoshan area were collected. Methylation-specific polymerase chain reaction (MSP) was used to detect the methylation status of the CpG island of MT-3 gene in these samples. Its relationship with clinicopatho-logical features was analyzed. Results:There were 20 (33.3%) cases with MT-3 methylation in the marginal tissues of esophageal cancer from high-risk area, which was higher than that in the normal mucosa from low-risk area (P=0.013). And there were 49 (81.7%) cases with MT-3 methylation in esophageal cancer tissues, which was higher than that in normal marginal tissues (P<0.001). But there was no significant difference in the methylation degree between middle-south of Hebei Province and Chaoshan area (P=0.739). Conclusion:MT-3 methylation widely exists in esophageal mucosa and carcinoma tissues. Acquired stimulus may be the main cause of these methylations.

Autophagy Induced by NGAL Protein in Esophageal Carcinoma Cells / 生物化学与生物物理进展

Previous studies suggest that NGAL (neutro phil gelatinase-associated lipocalin) is involved in the transformation and development of esophageal carcinoma. Alteration of NGAL expression can trigger the change of cellular morphology in esophageal carcinoma cells. However, the mechanisms remain unclear. To get a better understanding of NGAL function in esophageal carcinoma, NGAL protein was expressed in methylotrophic yeast, Pichia pastoris, and purified by chromatography. EC1.71 cells expressed high levels of NGALR (NGAL receptor) and EC109 cells expressed low levels of NGALR were used as cells model. The trafficking and the possible function of NGAL protein were then analyzed in the esophageal carcinoma cells. The results showed that 5-FAM-labeled recombinant NGAL protein could internalize into the EC1.71 and EC109 cells. Furthermore, the internalized NGAL protein could induce the alteration of cellular morphology, resulting in generation of autophagosome, transcriptional up-regulation of genes associated with autophagy and increase of phospho-ERK1/2 (p-ERK1/2). Interestingly, the treatment with the NGAL protein did not affect the intracellular iron level. These data indicate that induced autophagy by exogenous NGAL protein is a mechanism that internalized NGAL plays important roles in esophageal carcinoma cells, independent with NGAL-mediated iron transport process, while ERK1/2 signal pathway is involved in activation of autophagy by exogenous NGAL protein.

The promoter effects of sodium butyrate on the malignant transformation of the immortalized esophageal epithelium induced by human papillomavirus / 中华病理学杂志

<p><b>OBJECTIVE</b>Study on the promoter effects of sodium butyrate in high or low dosages on carcinogenesis process, based on the immortalization of human fetal esophageal epithelium induced by human papillomavirus (HPV) 18E(6)E(7) genes.</p><p><b>METHODS</b>The immortalized esophageal epithelium SHEE was treated with high concentration of the sodium butyrate (80 mmol/L) and then with low concentration (5 mmol/L) for 8 weeks respectively. The cells were cultured continuously without sodium butyrate for 14 weeks. The morphology, proliferation and apoptosis of the cells were studied by phase contrast microscopy, immunohistochemistry and flow cytometry. The dead and the viable cells were assayed by fluorescent microscopy with Hoechst 33342 and Propidium iodide staining. Tumorigenesis of the cells was assessed by soft agar colony formation and by transplantation of cells into nude mice and SCID mice.</p><p><b>RESULTS</b>When cells were exposed to high concentration of sodium butyrate, cell death was increased leaving few live cells. When cells were cultured in the medium with low concentration of sodium butyrate, the first proliferative stage appeared. Removal of the butyrate caused the cell to enter a crisis stage with a long doubling time resembling senescent cells. After the crisis stage, the cells progressed to the second proliferation stage with continuous replication and atypical hyperplasia. At the end of the second proliferative stage, carcinogenesis of the cells appeared with large colonies in soft-agar and tumor formation in transplanted SCID mice and nude mice.</p><p><b>CONCLUSIONS</b>The malignant change of the immortalized epithelium by the effects of sodium butyrate is the consequence of a two-stage mortality mechanism: cells death by butyrate cytotoxicity and cell crisis by abrogation of sodium butyrate. These data reveal that in high dosage, sodium butyrate induces cell death and in low dosage, it induces cell proliferation, which emphasizes the importance of butyrate as a promotor of carcinogenesis.</p>

Malignant transformation of the immortalized esophageal epithelial cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>Immortal cell line of human embryonic esophageal epithelium (SHEE) was induced by E6E7 genes of human papillomavirus (HPV) type 18 in our laboratory. To identify the fully malignant transformation at its 85th passage (SHEE85), the malignant phenotype, tumorigenesis and invasive potency were studied.</p><p><b>METHOD</b>The cultured SHEE85 cells were observed under the light and the electron microscope (EM) for cell morphology, analyzed by flow cytometry for cell cycle. The tumorigenesis was assayed by plating cells in soft-agar and transplanting cells into the nude mice and SCID mice. To detect invasive potency, cells were cultured on amniotic membrane in vitro and transplanted into peritoneal cavity of mice in vivo.</p><p><b>RESULTS</b>SHEE85 cells were crowded in cultivation with different sizes and shapes under light microscope, and displayed proliferative morphology under EM. Proliferative index was 47% with 12% hyperploidy cells in determination of DNA histogram. Many large colonies grew in soft-agar (4%) and the transplanted tumors were found in all 4 nude and 4 SCID mice, with strong invasive potency demonstrated in vitro and in vivo.</p><p><b>CONCLUSION</b>The immortal esophageal epithelial cell line induced by HPV18 E6 E7 is derived from a fully malignant transformation with a strong invasive potency at the 85th passage. It is also a reliable model for studying the cellular and molecular mechanisms of carcinogenesis of the esophageal carcinoma.</p>

Study of Location in Tumor Bearing Nude Mice of Monoclonal Antibody to Human Esophageal Carcinoma / 中山大学学报(医学科学版)

【Objective】 To study the location effect of the Mc Ab G9 to human esophageal carcinoma in tumor bearing nude mice. 【Methods】 125　I-G9 was prepared by Chloramine-T method. The distribution of 125 　 I-G9 was detected at different time (24, 48, and 72 h) after peritoneal injecti on. The percentage of the injected dose per gram of tissue(%ID/g) and the ratio of Tumor/non-Tumor were calculated. 【Results】 The distribution of 125　 I -G9 in tumor at the third day was showed by autoradiography obviously higher th an in other organ/tissue (except blood) and the highest is at the 48 h. The T/NT values are 2-7. The autoradiography indicated that radioactivity concentrated in tumor tissue. The concentration in tumor edge is more obvious than in the ce nter. 【Conclusion】 125　I-G9 has a considerable targeting activity and can well locate in esophageal carcinoma tissue in tumor bearing nude mice.

Study on etiology of esophageal carcinoma:retrospect and prospect / 中国癌症杂志

Esophageal carcinoma is one of the top frequently occur malignant cancers, especially in Chinese.Studies on esophageal carcinoma have suggested that genetic predisposition, dietary or environmental factors, such as nitrosamine, tobacco smoking, malnutrition, trace element deficieny and fungus toxin could be important in the carcinogenesis of this cancer.

The Effects of Arsenite Trioxide on the Transplanted Hepatic Carcinoma in Mice / 中国肿瘤生物治疗杂志

Objective: To investigate the antitumor effects of arsenic trioxide (As 2 O 3 ) on solid tumor in vivo , the transplanted hepatic carcinoma of mice were treated with various dosages of As 2 O 3 . Methods: After 50 mice were injected intraperitoneally with 0,2, 4, 6, 8 ?mol/g As 2 O 3 respectively for observation of acute toxicity, 1, 2, 3 ?mol/g were selected for this experiment. Eighty mice were transplanted with hepatic carcinoma cells (1.5?10 6 cells/each side) into both subaxillae. As 2 O 3 in 0, 1, 2 and 3 ?mol/g were injected into right subaxilla respectively once every day for 10 days. At the 30th day after transplanted hepatic carcinoma cell, mice were killed and the size of solid tumors was measured. The chronic cytotoxicity of As 2 O 3 was observed in these mice.Results: In right subaxillae tumors, which were injected directly with As 2 O 3 , were apparent smaller than that in the left ( P

The Effects of Arsenite Trioxide in Various Concentrations on the Esophageal Carcinoma Cell Line / 中国肿瘤生物治疗杂志

Objective: To further study the effects of As 2 O 3 in various concentrations on the esophageal carcinoma cell line. Methods: The esophageal malignant transformed epithelial cells (SHEEC1) were induced by HPV18 in synergy with TPA in our laboratory. The cells cultured in flask and 24 wells plate were treated by As 2 O 3 with concentrations of 1, 3 and 5 ?mol/L for 2, 4, 8, 16, 24 h respectively. The morphologic changes of cells were observed under election microscopy. The mitotic index (MI) of living cells was calculated by phase contrast microscopy and the cells with TdR uptake were examined by autoradiography. The proliferative index (PI) and apoptotic index (AI) were assayed by flow cytometry. Results: A low dosage of As 2 O 3 (1.0 ?mol/L) enhancing the protiferative rate of SHEEC1 was demonstrated with TdR uptake, MI and PI increased. The high AI and low PI were found in the high concentrations (3 and 5 ?mol/L)of As 2 O 3 . The morphological changes of apoptosis and necrosis were found in 24 h after As 2 O 3 in high concentrations (3 and 5 ?mol/L) administrated. Conclusion: The effects of As 2 O 3 in various concentrations are different. Low concentration of As 2 O 3 promotes the proliferation of the esophageal carcinoma cells by increment of DNA synthesis. In high concentration of As 2 O 3 apoptosis and necrosis are induced.

MATHEMATICAL CALCULATION OF AMINO ACID COMPLEMENTATION WITHIN VARIOUS FOODS / 营养学报

Based on amino acid score of food, this article presents an "Amino Acid Score Difference (AASD) " for protein quality evaluation, the minus value of AASD representing the limiting amino acid and its number re- presenting the degree. The minus value in one food can be compensated by the positive value in another when we directly select the rational couple for amino acid complementation in diet. In addition, a calculation formula is introduced for amino acid complementation in two kinds of food or in mixed diet including many foods. It gives an effective means in evaluating the nutritional value of protein in foods and planning an ideal diet by selecting foods on the basis of amino acid complementation

CYTOGENETIC STUDIES ON HPV-18-IMMORTALIZED CELLSFROM ESOPHAGEAL EPITHELIA OF HUMAN EMBRYO / 解剖学报

Objective To study the cytogenetic changes in HPV-immortalized cells(SHEE)for further investigating the esophageal carcinogenesis. Methods Giemsa staining was used to show the modal number of chromosomes.G-banding was done to observe the chromosomal aberrations.Fluorescence in situ hybridization(FISH)of the interphase nuclei with the centromere probes of chromosome 1,7 and 8 were performed to determine the numerical abnormalities. Results The modal numbers at passage 10 and 20 were 58-63 and 57-64, respectively.Passage 61 had a bimodal distribution 58-61 and 63-65.The structural aberrations could almost be found in all of karyotypes.The following structural aberrations were identified:1.del(1)(q12);2.del(1)(p32);3.der(4),t(4;?)(q31;?);4.der(5),t(5:?)(q31;?).FISH results showed that trisomy 1 and tetrasomy 7 markedly increased with the increase of passages and disomy 8 kept in faint change in all passages.Conclusion The modal number moved right slowly in the graph of the modal distribution and the increases of chromosomal numbers were in imbalance with increases of passages of SHEE.The structural aberrations of chromosome were found in most of karyotypes.Our results suggest that the cell immortalization is a multistep process involved in the multiple chromosomes.;