Polyimide covalent organic frameworks bearing star-shaped electron-deficient polycyclic aromatic hydrocarbon building blocks: molecular innovations for energy conversion and storage.

Polyimide covalent organic frameworks (PI-COFs) are outstanding functional materials for electrochemical energy conversion and storage owing to their integrated advantages of the high electroactive feature of polyimides and the periodic porous structure of COFs. Nevertheless, only anhydride monomers with C2 symmetry are generally used, and limited selectivity of electron-deficient monomers has become a major obstacle in the development of materials. The introduction of polycyclic aromatic hydrocarbons (PAHs) is a very effective method to regulate the structure-activity relationship of PI-COFs due to their excellent stability and electrical properties. Over the past two years, various star-shaped electron-deficient PAH building blocks possessing different compositions and topologies have been successfully fabricated, greatly improving the monomer selectivity and electrochemical performances of PI-COFs. This paper systematically summarizes the recent highlights in PI-COFs based on these building blocks. Firstly, the preparation of anhydride (or phthalic acid) monomers and PI-COFs related to different star-shaped PAHs is presented. Secondly, the applications of these PI-COFs in energy conversion and storage and the corresponding factors influencing their performance are discussed in detail. Finally, the future development of this meaningful field is briefly proposed.

Brain uptake of a non-radioactive pseudo-carrier and its effect on the biodistribution of [(18)F]AV-133 in mouse brain.

INTRODUCTION: 9-[(18)F]Fluoropropyl-(+)-dihydrotetrabenazine ([(18)F]AV-133) is a new PET imaging agent targeting vesicular monoamine transporter type II (VMAT2). To shorten the preparation of [(18)F]AV-133 and to make it more widely available, a simple and rapid purification method using solid-phase extraction (SPE) instead of high-pressure liquid chromatography (HPLC) was developed. The SPE method produced doses containing the non-radioactive pseudo-carrier 9-hydroxypropyl-(+)-dihydrotetrabenazine (AV-149). The objectives of this study were to evaluate the brain uptake of AV-149 by UPLC-MS/MS and its effect on the biodistribution of [(18)F]AV-133 in the brains of mice. METHODS: The mice were injected with a bolus including [(18)F]AV-133 and different doses of AV-149. Brain tissue and blood samples were harvested. The effect of different amounts of AV-149 on [(18)F]AV-133 was evaluated by quantifying the brain distribution of radiolabelled tracer [(18)F]AV-133. The concentrations of AV-149 in the brain and plasma were analyzed using a UPLC-MS/MS method. RESULTS: The concentrations of AV-149 in the brain and plasma exhibited a good linear relationship with the doses. The receptor occupancy curve was fit, and the calculated ED50 value was 8.165mg/kg. The brain biodistribution and regional selectivity of [(18)F]AV-133 had no obvious differences at AV-149 doses lower than 0.1mg/kg. With increasing doses of AV-149, the brain biodistribution of [(18)F]AV-133 changed significantly. CONCLUSION: The results are important to further support that the improved radiolabelling procedure of [(18)F]AV-133 using an SPE method may be suitable for routine clinical application.

Mapping the target localization and biodistribution of non-radiolabeled VMAT2 ligands in rat brain.

Imaging targeting vesicular monoamine transporter (VMAT2) alterations is a sensitive tool for early diagnosis of Parkinson's disease. Our group has reported several novel 2-amino-DTBZ derivatives as potential VMAT2 imaging agents. The objective of this paper is to develop a non-radiolabeled methodology to screen the candidate compounds for accelerating the drug discovery process. 9-[(18)F]fluoropropyl-(+)-dihydrotetrabenazine ([(18)F]AV-133) is a PET imaging agent targeting VMAT2 binding sites in the brain. Nonradioactive AV-133 was injected (iv) into rats, at the end of the allotted time, the animals were killed and six regions of brain and plasma from each animal were processed for quantitative measurement of AV-133 by LC-MS/MS. These data were converted to the percentage injected dose per gram tissue weight (%ID/g tissue) and the brain target tissue to background ratios to allow direct comparison with data obtained by gamma counting of the injected radioactive [(18)F]AV-133. The %ID/g and the brain target tissue to background ratios calculated using the LC-MS/MS method were highly correlated to the values obtained by standard radioactivity measurements of [(18)F]AV-133. The pattern of AV-133 in rat brain was consistent with the known distribution of VMAT2. The concordance indicated that high-sensitivity LC-MS/MS is an indispensable tool in evaluating the quantity of administered chemical in tissue as part of the development of new molecular imaging probes. Furthermore, several novel 2-amino-DTBZ derivatives were detected using this methodology, and their biodistribution data in rat brain were obtained. The information about target engagements of candidates was provided.

Correlation between expression of extracellular matrix metalloproteinase inducer and matrix metalloproteinase-2 and cervical lymph node metastasis of nasopharyngeal carcinoma.

OBJECTIVES: We evaluated the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase-2 (MMP-2) in nasopharyngeal carcinoma (NPC) and studied their relationship with cervical lymph node metastasis. METHODS: Immunohistochemical staining was used to detect the expression of EMMPRIN and MMP-2 in specimens from patients with chronic nasopharyngitis (CN), nonmetastastic NPC (NM-NPC), and lymph node-metastatic NPC (LNM-NPC). RESULTS: The rates of positive EMMPRIN expression in CN, NM-NPC, and LNM-NPC were 13.3%, 30.0%, and 66.7%, respectively. Significant differences were found between the rates in CN and LNM-NPC (p <0.01) and between the rates in NM-NPC and LNM-NPC (p = 0.01). In the LNM-NPC group, NPC cells had a higher rate of expression of EMMPRIN in tumor metastases than in the primary tumor (81.8% versus 66.7%; p = 0.01). The rates of positive MMP-2 expression in CN, NM-NPC, and LNM-NPC were 13.3%, 35.0%, and 60.6%, respectively. A significant difference was found between the rates in CN and LNM-NPC (p < 0.01). In the LNM-NPC group, NPC cells had a higher rate of MMP-2 expression in tumor metastases than in the primary tumor (72.7% versus 60.6%; p <0.01). The expressions of MMP-2 and EMMPRIN were highly correlated (rs = 0.466; p <0.01). CONCLUSIONS: Nasopharyngeal carcinoma cells may attain enhanced metastastic capability through the expression of MMP-2 induced by EMMPRIN.

Potential role of minichromosome maintenance protein 2 as a screening biomarker in esophageal cancer high-risk population in China.

Minichromosome maintenance proteins are novel proliferative markers that have been proposed as diagnostic markers in many cancers. We evaluated the potential role of minichromosome maintenance protein 2 as a screening biomarker and compared it with proliferating cell nuclear antigen and Ki67 in a population survey of esophageal squamous cell carcinoma. A total of 299 esophageal samples from a high-risk region in China, including 171 from an endoscopy population survey, 30 from brushing cytology, and 98 from surgery and autopsy, underwent immunostaining with minichromosome maintenance protein 2, proliferating cell nuclear antigen, and Ki67 antibodies. Minichromosome maintenance protein 2 expression was confined to the proliferative compartment of normal and abnormal esophageal epithelium and particularly manifested in the surface layer of dysplasia and carcinoma in situ. The expression of proliferating cell nuclear antigen and Ki67 was positively correlated with that of minichromosome maintenance protein 2 (r(s) >0.39, P < .01); but their positive nuclei seldom reached the surface layer, and the labeling indices were significantly lower than those for minichromosome maintenance protein 2 in dysplasia (P < .05) and carcinoma in situ (P < .001). The sensitivity and specificity of minichromosome maintenance protein 2 in diagnosing dysplasia were 91.3% and 61.8%, respectively, higher than those for proliferating cell nuclear antigen (88.4% and 47.1%) and Ki67 (78.3% and 57.8%). Nine of 10 cancer and paracancerous surface-brushing samples expressed minichromosome maintenance protein 2, and the detection was higher than that for proliferating cell nuclear antigen (8/10 and 7/10) and Ki67 (7/10 and 7/10). However, none of 10 normal surface-brushing samples expressed the 3 markers. Minichromosome maintenance protein 2 is more sensitive and specific than proliferating cell nuclear antigen and Ki67 in indicating esophageal dysplasia. Minichromosome maintenance protein 2 immunostaining combined with surface brushing could be valuable in screening patients at high risk of cancer in mass surveys.

Image analysis of DNA content and nuclear morphometry for predicting radiosensitivity of nasopharyngeal carcinoma.

OBJECTIVE: To investigate the relationship among nuclear DNA content, nuclear morphology, clinical response, and radiosensitivity in nasopharyngeal carcinoma (NPC) and the suitability of image cytometric analysis of DNA content and nuclear morphology for predicting radiosensitivity of NPC prior to radiotherapy. STUDY DESIGN: Nuclear DNA content and morphology features were detected by image cytometric analysis in 51 biopsy specimens of NPC prior to radiotherapy. The radiotherapeutic effect experienced by the NPC patients was classified as CR (complete response [i.e., complete tumor disappearance]) and PR (partial response [i.e., residual tumor]) according to pathologic analysis of tumor specimens after completion of the scheduled treatment. RESULTS: The mean DNA index; the percentage of cells with the DNA pattern of 2C, 5C, aneuploidy respectively; the mean nuclear area; the mean nuclear perimeter and the mean nuclear diameter in the CR group were significantly higher than they were in the PR group. CONCLUSION: DNA content and nuclear morphometry by image cytometric analysis were significantly correlated with patient outcome and radiosensitivity of NPC. Other measurements of more biomarkers for predicting the radiosensitivity of NPC await further study.

Autophagy and endocytosis in the amnion.

To search for the origin of nutrition in the amnion, we focused attention on both endocytotic and autophagic pathways. Using ultrastructural and biochemical methods, we examined 20 human amnions at term gestation. The uptake of horseradish peroxidase (HRP) was used for the detection of endocytosis. Transfection of the LC3-GFP plasmid and staining with monodansylcadaverine (MDC) and LysoTracker red (LTR) were used to demonstrate the formation of autophagic vacuoles. In addition, two autophagic genes, beclin 1 and Atg5, were assayed by RT-PCR. Within the amniotic epithelial (AE) cells, autophagic vacuoles contained organelles and cytoplasmic components and were enclosed by a double membrane. They contained autophagosomes with transfected LC3-GFP that stained positive for MDC and autolysosomes that stained positive for LTR. Endocytosis was an extremely active process in the cellular uptake of fluid and fluid contents and led to formation of vesicles and endosomes, which were found to be positive by HRP test. Many uniform vesicles were collected in the multivesicular bodies (MVBs). Finally, both endosomes and autophagosomes were fused and degraded by lysosomes. The data also demonstrated that large autophagosomes engulfed some endosomes or MVBs. Transcription of beclin 1 and Atg5 occurred in the amnion at term gestation. Taken together, these results show that AE cells have active endocytotic and autophagic capacities and that lysosomes are involved in the intracellular degradation of endosomes and autophagosomes. Sometimes the autophagic and endocytotic pathways converge. This study suggests that of endocytosis and autophagy activities in AE cells can be induced by nutrient limitation and are probably also evoked in response to some hormones in the amniotic fluid. Activation of both endocytotic and autophagic pathways plays different roles in the ability of the cell to acquire nutrients needed for its survival.

Analysis of basement membrane structure and inflammation during the development of esophageal squamous cell carcinoma in the Chinese Chaoshan high risk region.

BACKGROUND & AIMS: To investigate relationships between basement membrane structure, inflammation, beta1 integrin expression, activation of ERK/MAPK signaling pathways, and cell proliferation in esophageal mucosa at various stages during the evolution of esophageal squamous cell carcinoma. METHODS: Three tissue arrays were made of 228 tissue cores from 428 surgically-resected specimens. The arrays included 26 samples of normal epithelium, 28 with hyperplasia, 18 with dysplasia, 27 with carcinoma in situ and 129 with invasive carcinoma. In addition, 21 cases of hyperplasia, 13 cases of dysplasia and 13 case of carcinoma in situ were obtained by manual microdissection of unfixed frozen tissue. Hematoxylin and eosin stained sections were used to evaluate the epithelium and inflammation. The periodic acid-Schiff stain and an immunohistochemical stain for laminin were used to examine the structure of basement membranes. The expression of beta1 integrin, p-ERK, and Ki67 were evaluated by quantitative immunohistochemistry. RT-PCR and Western blots were also used to detect expression of beta1 integrin. RESULTS: Quantitative scales were developed to classify basement membrane structure and inflammation. Basement membrane alterations correlated with the degree of epithelial change (chi2 = 501.9, p < 0.01) and with the degree of lymphocytic infiltration in the lamina propria and epithelium (chi2 = 273.4, p < 0.01). There was a significant relationship between the extent of basement membrane alteration and the expression of beta1 integrin, p-ERK, and Ki67. CONCLUSIONS: The correlations suggest that there is a direct relationship between basement membrane structure and the development of esophageal squamous cell carcinoma.

Altered expression of ezrin in esophageal squamous cell carcinoma.

Ezrin is a membrane-cytoskeletal linker belonging to the ezrin-radixin-moesin (ERM) family and has been suggested to be involved in tumorigenesis. In this study we investigated ezrin expression pattern in normal esophageal mucosa and esophageal squamous cell carcinoma (ESCC) and the correlation with clinical characteristics. Immunohistochemical staining showed a tendency for ezrin to translocate from membrane to cytoplasm in the progression from normal epithelium to invasive carcinoma of the esophagus. By Western blot, we found that ezrin expression was downregulated in 13 ESCC specimens and upregulated in 36 others. Moreover, quantitative real-time RT-PCR demonstrated that ezrin mRNA level in normal esophageal mucosa was 3.60 +/- 3.60 times that in ESCC (p<0.001). Proliferating cell nuclear antigen (PCNA) expression level was higher in ezrin downregulated group compared with that in ezrin upregulated group (p<0.05). However, there was no significant association between ezrin expression and clinical characteristics. The results suggested that the localization of ezrin by immunohistochemistry may be useful in the diagnosis of ESCC, and ezrin may play a suppressive role in the tumorgenesis of ESCC.

[Effects of selenium and B-27 supplements on viability and differentiation of neural stem cell in newborn rat].

OBJECTIVE: To assess how trace element selenium and B27 supplements affect the neural stem cell (NSc) differentiation in vitro. METHODS: The development and differentiation of NSc from the newborn rat were observed with primary culture and subculture during treating by sodium-selenite, and selenium-methyl-cysteine (SMC). The immunocytochemistry techniques were used to identify the NSc and mature protein expression with neuron marker beta-tubulin, astrocyte marker GFAP, and oligodendrocyte marker CNPase. The neurosphere morphology and neurite outgrowth were observed. RESULTS: Adding the complete B-27 serum-free supplement, Selenium could promote the neurosphere viability, development and differentiation. Without selenium and B-27, neurosphere could not survive and differentiate. Without B-27 in the medium but there containing selenium, the neurosphere could promote the viability and development into neuron, astrocyte and oligodendrocyte, as compared with the no-containing B-27 and selenium groups, these differentiated cells might have more quantity, more branches and better morphological nerve net. The count of the neuron, astrocyte and oligodendrocyte was 11.2/Hp, 16.1/Hp and 9.3/Hp. CONCLUSIONS: The selenium should be very important for neural stem cells' survival. Selenium could promote the neurosphere cells differentiation and development.

Detection of HSV and EBV in esophageal carcinomas from a high-incidence area in Shantou China.

An association between viral infection, particularly the human papillomavirus, and the development of esophageal carcinoma (EC) has been reported. However, reports concerning the relationship between herpes simplex virus (HSV) and Epstein-Barr virus (EBV) with EC are few. There are geographic variations in infection rates. This study was aimed to determine the co-incidence of infection of the two viruses' with esophageal carcinoma and the differentiation of cancer tissues and lymphocytes infiltration in the tumor stroma of the high-incidence area of Shantou China. To determine the association between viral infection (HSV and EBV) and EC, we applied in situ hybridization (ISH) and immunohistochemistry (IHC) in 164 esophageal carcinoma surgical specimens from the high-incidence area of Shantou China. HSV DNA and HSVI, II protein expression were found in 52 (31.7%) of the 164 tumors; EBV EBER and LMP-1 proteins were identified in only 10 (6.1%) carcinoma specimens by in situ hybridization and immunohistochemistry. In histopathology analysis, the positive cases of HSV appeared to be more predominant in well and moderately differentiated squamous cell carcinomas, and the positive cases of EBV were found in poorly differentiated squamous cell carcinomas or undifferentiated carcinomas with intense lymphoid infiltration. Our results confirm the involvement of HSV and EBV in esophageal carcinomas and the relationship between HSV and EBV infection and esophageal carcinoma cell differentiation with lymphocyte infiltration in the tumor stroma. However, the two herpes viruses, HSV and EBV, particularly the human HSV may be one of the etiological factors in development of this malignancy among the high-incidence population of Shantou China.

Prognostic and clinicopathological features of E-cadherin, alpha-catenin, beta-catenin, gamma-catenin and cyclin D1 expression in human esophageal squamous cell carcinoma.

AIM: To investigate the expression of E-cadherin, alpha-catenin, beta-catenin, gamma-catenin and cyclin D(1) in patients with esophageal squamous cell carcinoma (ESCC), and analyze their interrelationship with clinicopathological variables and their effects on prognosis. METHODS: Expression of E-cadherin, alpha-catenin, beta-catenin, gamma-catenin and cyclin D(1) was determined by EnVision or SABC immunohistochemical technique in patients with ESCC consecutively, their correlation with clinical characteristics was evaluated and analyzed by univariate analysis. RESULTS: The reduced expression rate of E-cadherin, alpha-catenin, beta-catenin and gamma-catenin was 88.7%, 69.4%, 35.5% and 53.2%, respectively. Cyclin D1 positive expression rate was 56.5%. Expression of gamma-catenin was inversely correlated with the degree of tumor differentiation and lymph node metastasis (chi(2) = 4.183 and chi(2) = 5.035, respectively, P<0.05), whereas the expression of E-cadherin was correlated only with the degree of differentiation (chi(2) = 5.769, P<0.05). Reduced expression of E-cadherin and gamma-catenin was associated with poor differentiation of tumor, reduced expression of gamma-catenin was also associated with lymph node metastasis. There obviously existed an inverse correlation between level of E-cadherin and gamma-catenin protein and survival. The 3-year survival rates were 100% and 56% in E-cadherin preserved expression group and in reduced expression one and were 78% and 48% in gamma-catenin preserved expression group and in reduced expression one, respectively. The differences were both statistically significant. Correlation analysis showed the expression level of alpha-catenin correlated with that of E-cadherin and beta-catenin (P<0.05). CONCLUSION: The reduced expression of E-cadherin and gamma-catenin, but not alpha-catenin, beta-catenin and cyclin D1, implies more aggressive malignant behaviors of esophageal carcinoma cells and predicts the poor prognosis of patients.

Clinicopathologic analysis of esophageal and cardiac cancers and survey of molecular expression on tissue arrays in Chaoshan littoral of China.

AIM: To investigate clinical and pathologic data of esophageal carcinoma (EC) and cardiac carcinoma (CC) among residents in Chaoshan region of China. METHODS: Clinical and pathologic data of 9 650 patients with EC and 4 173 patients with CC in the Chaoshan population were collected and analyzed. Moreover, Chaoshan esophageal carcinoma tissue arrays were made for high-throughput study. RESULTS: Male to female ratio was 3:1 in patients with EC and 4.75:1 in CC. The average age of the occurrence of EC was 54.6 years, and of CC was 58.1 years. For both EC and CC, age at diagnosis was a little younger in Chaoshan region than in most other areas. The most commonly affected site of esophageal carcinoma was the middle third of esophagus (72.0%); the second was the lower third (15.3%). The main gross type of esophageal carcinoma was ulcerative type (41.50%); the medullary type was the second (39.6%). Squamous cell carcinoma accounted for the overwhelming majority of esophageal cancer (96.4%); adenocarcinoma accounted for the overwhelming majority of cardiac carcinoma (94.5%). Chaoshan esophageal carcinoma tissue arrays were easily for high-throughput study, and tissue cores with a diameter of 1.5 mm could better keep more structure for molecular expression study. CONCLUSION: Both EC and CC are common in males. The average occurrence age of EC and CC is younger in Chaoshan than in most other regions of China. The most commonly affected site of esophageal carcinoma was the middle third of esophagus (72.0%). Squamous cell carcinoma accounted for the overwhelming majority of esophageal cancer; adenocarcinoma accounted for the overwhelming majority of cardiac carcinoma. Tissue arrays technology is applicable for rapid molecular profiling of large numbers of cancers in a single experiment.

Correlation between expression of human telomerase subunits and telomerase activity in esophageal squamous cell carcinoma.

AIM: To investigate telomerase activity and hTERT, TP-1 expression and their relationships in esophageal squamous cell carcinoma (ESCC). METHODS: Telomerase activity was measured in 60 ESCC tissues using telomeric repeat amplification protocol (TRAP) assay by silver staining. In situ hybridization was used for detecting hTERT and TP-1mRNA. RESULTS: The telomerase activity was detected in 83.3% of ESCC tissues. The difference of telomerase activity was significant between well and poorly cancer differentiated lesions (P<0.05). The positive rate of telomerase activity was higher in patients with lymphatic metastasis than in patients without lymphatic metastasis. In cancer tissues hTERT mRNA expression was 75% and TP-1 mRNA expression was 71.7%. The expression of hTERT, TP-1 mRNA in well and poorly differentiated carcinoma was not significant. The expression of hTERT mRNA was correlated with telomerase activity, but TP-1 mRNA expression was not correlated with it. CONCLUSION: Telomerase activity and hTERT, TP-1 mRNA expression are up-regulated in ESCC. Telomerase activity in ESCC is correlated with lymphatic metastasis and cancer differentiation. Telomerase activity may be used as a prognostic marker in ESCC. hTERT mRNA expression is correlated with telomerase activity. Enhanced hTERT mRNA expression may initially comprehend the telomerase activity level, but it is less sensitive than TRAP assay.

The inhibition of growth and angiogenesis in heterotransplanted esophageal carcinoma via intratumoral injection of arsenic trioxide.

To investigate the antitumor action of arsenic trioxide (As2O3) by intratumoral injection into solid tumors, tumor growth inhibition (TGI) and angiogenesis of heterotransplanted esophageal carcinoma in mice was carried out. The cultured human esophageal carcinoma cells were inoculated into both laterals of the abdominal wall of severe combined immunodeficient (SCID) mice. When both lateral tumors had grown to about 10x8x5 mm(3), the right tumors were treated with an intratumoral injection of As2O3 in dosage of 1, 5 and 10 microg per day, respectively, for 10 days sequentially. Left tumors were treated with PBS (phosphate buffer solution) as control. The weight of transplanted tumor masses were measured and counted for TGI. The tissue of tumor, liver, kidney, heart, lung and brain was examined histopathologically and tumor tissues were examined by light- or electron-microscope. Ki-67 and CD34 were assessed by immunohistochemistry and positive nuclei of Ki-67 and microvessel density (MVD) labeled by CD34 were measured. The results revealed that on the 20th day after the first injection, As2O3-treated tumors were suppressed markedly as compared with the contrarily situated tumor, accompanied by a marked apoptosis and necrosis in tumor cells. The tissue of liver, kidney, heart, lung and brain was unaffected by As2O3. MVD in tumor tissue was decreased in the right side tumor with the significant difference in the 5 micro g and 10 micro g group (p<0.01). TGI was 5.80 (p>0.05), 58.66 (p<0.01) and 73.97% (p<0.01) in the 1, 5 and 10 micro g groups respectively, but 2.21% (p>0.05) in the control group. Conclusively, a repeated administration of As2O3 (5 and 10 microg x 10) induced an increase of tumor growth inhibition and decrease of angiogenesis in the solid tumor in tumor progressive periods. These results suggest that intra-tumoral injection of As2O3 may be investigated as a modality to treat some solid tumors.

Upregulated expression of Ezrin and invasive phenotype in malignantly transformed esophageal epithelial cells.

AIM: To investigate the correlation between ezrin expression and invasive phenotype formation in malignantly transformed esophageal epithelial cells. METHODS: The experimental cell line employed in the present study was originated form the progressive induction of a human embryonic esophageal epithelial cell line (SHEE) by the E6E7 genes of human papillomavirus (HPV) type 18. The cells at the 35(th) passage after induction called SHEEIMM were in a state of immortalized phase and used as the control, while that of the 85(th) passage denominated as SHEEMT represented the status of cells that were malignantly transformed. The expression changes of ezrin and its mRNA in both cell passages were respectively analyzed by RT-PCR and Western blot. Invasive phenotype was assessed in vivo by inoculating these cells into the severe combined immunodeficient (SCID) mice via subcutaneous and intraperitoneal injection, and in vitro by inoculating them on the surface of the amnion membranes, which then was determined by light microscopy and scanning electron microscopy. RESULTS: Upregulated expression of ezrin protein and its mRNA was observed in SHEEMT compared with that in SHEEIMM cells. The SHEEMT cells inoculated in SCID mice were observed forming tumor masses in both visceral organs and soft tissues in a period of 40 days with a special propensity to invading mesentery and pancreas, but did not exhibit hepatic metastases. Pathologically, these tumor cells harboring larger nucleus, nucleolus and less cytoplasm could infiltrate and destroy adjacent tissues. In the in vitro study, the inoculated SHEEMT cells could grow in cluster on the amniotic epithelial surface and intrude into the amniotic stroma. In contrast, unrestricted growth and invasiveness were not found in SHEEIMM cells in both in vivo and in vitro experiment. CONCLUSION: The upregulated ezrin expression is one of the important factors that are possibly associated with the invasive phenotype formation in malignantly transformed esophageal epithelial cells.

Effects of selenium and iodine on the expression of c-fos and c-jun mRNA and their proteins in cultured rat hippocampus neurons.

OBJECTIVE: To study the effect of selenium (Se) and iodine (I) and the compound of both on the proto-oncogenes c-fos and c-jun mRNA and their protein expression in the cultured rat hippocampus neurons. METHODS: Using the technique of serum free hippocampus neuron culture, different doses of Se and I and Se + I compound were added into the medium. The expression of the mRNA of c-fos, c-jun in hippocampus neurons cultured for 1, 3, 5, 7 and 10 d were studied using both in situ hybridization and SABC immunohistochemical technique. RESULTS: Both Se and I could enhance the expression of c-fos, c-jun mRNA and their proteins, especially the combination of I and Se able to give a remarkable effect on c-jun mRNA expression. CONCLUSIONS: Se and I may effect the expression of both c-fos and c-jun mRNA, especially the c-jun mRNA and its protein of hippocampus neurons, and thus may effect the differentiation and development of neurons.

[The promoter effects of sodium butyrate on the malignant transformation of the immortalized esophageal epithelium induced by human papillomavirus].

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Relationship between Egr-1 gene expression and apoptosis in esophageal carcinoma and precancerous lesions.

AIM: To study the expression of early growth response gene-1 (Egr-1 gene) and Bcl-X/(L) protein and its relationship with the cell apoptosis in human esophageal carcinoma (EC) and precancerous lesions. METHODS: In situ hybridization(ISH), immunohistochemistry (IHC) and TUNEL method were used respectively to detect Egr-1mRNA, Egr-1 protein, apoptosis related-protein Bcl-X/(L) and cell apoptosis in situ from 66 cases of esophageal squamous cell carcinoma and their upper cut edge and paracancerous mucosa. RESULTS: Egr-1 gene in situ hybridization, Bcl-X/(L) immunohistochemistry positive products were located in the cytoplasm, while Egr-1 immunohistochemistry and TUNEL positive signal were located in the nuclei. The apoptosis index(AI) and the frequency of apoptosis occurrence were increased gradually from precancerous lesion to cancer (P<0.01) and the expression of Egr-1mRNA and Egr-1 protein in dysplasia was the highest among all specimens (P<0.01). The AI of Egr-1 positive cancer tissues was much higher than that of Egr-1 negative cancer tissues (P<0.01), while the AI of Bcl-X/(L) positive cancer tissues was much lower than that of Bcl-X/(L) negative cancer tissues (P<0.01). The AI and Egr-1 expression were not correlated with invasiveness and lymphatic metastasis in EC. CONCLUSION: Cell apoptosis was present through esophageal carcinogenesis. The expression of Egr-1 mRNA and Egr-1 protein were high in precancerous lesion of esophagus. The AI was increased significantly in Egr-1 positive squamous cell carcinoma. Egr-1 might promote apoptotic effect. Egr-1 expression and cell apoptosis may have an important biological significance in esophageal carcinogenesis.

Morphometric analysis of AgNORs in nonkeratinizing carcinoma and adjacent normal epithelia in the nasopharynx.

OBJECTIVE: To evaluate the proliferative activity of different types of nonkeratinizing carcinoma and adjacent normal epithelia in the nasopharynx by the quantitative assessment of argyrophilic nucleolar organizer region (AgNOR) proteins. STUDY DESIGN: Silver staining of nucleolar organizer regions (NORs) was applied to 70 paraffin sections of nonkeratinizing carcinoma in nasopharyngeal biopsies. Fifty-four of the 70 cases had differentiated nonkeratinizing carcinoma (DNC), and the remaining 16 had undifferentiated carcinoma (UC). Nineteen of these 70 samples proved to contain, besides carcinoma, normal epithelia (NE), which was used as a control. The epithelial cells and cancer cells were analyzed for their AgNOR features by image cytometric analysis. RESULTS: As compared with normal epithelia, significant differences were found in mean nuclear area, AgNOR count, mean AgNOR area, AgNOR area ratio and AgNOR area/count ratio between NE and DNC (P < .05) and in mean nuclear area, mean AgNOR area and AgNOR area/count ratio between NE and UC (P < .001). Further, the differences in mean nuclear area, mean AgNOR area and AgNOR area/count ratio were statistically significant between DNC and UC. CONCLUSION: The evaluation of AgNORs is a useful histologic assessment of rapidity of cell proliferation in malignant and benign lesions and demonstrated that UC had more rapidly proliferative activity than DNC in this study.