Perivascular epithelioid cell tumor of male pelvic cavity: a case report and literature review.

Perivascular epithelioid cell tumors (PEComas) are a family of rare mesenchymal neoplasms. The PEComas, composed of epithelioid and spindle cells, have the same cellular and immunohistochemical features but are found in different visceral and soft tissue sites. Here, we report the histological and immunohistochemical features of one case of PEComa restricted in the pelvic visceral peritoneum of a male patient. The patient was treated with radical surgery, and was well and on follow-up visits without tumor recurrence.

Aberrant expression of the von Hippel-Lindau gene in human endometrial hyperplasia and endometrial carcinoma.

INTRODUCTION: The purpose of this study was to determine whether aberrant expression of the von Hippel-Lindau (VHL) gene in human hyperplastic and malignant endometrial tissues was involved in endometrial carcinogenesis. METHODS: Fresh tissue samples of endometrial hyperplasia consisting of simple (n = 26), complex (n = 23), and atypical hyperplasia (n = 20); endometrial carcinoma (n = 17); and normal endometrium (n = 40) were measured using Western blotting and real-time reverse transcription polymerase chain reaction. Paraffin-embedded sections of endometrial hyperplasia (n = 90), endometrial carcinoma (n = 30), and normal endometrium (n = 60) were detected by immunohistochemical method. RESULTS: Von Hippel-Lindau staining was present in the cytoplasm of epithelial cells and stroma. A decreased expression of VHL mRNA in endometrial hyperplasia from simple, complex, to atypical hyperplasia was observed. There were statistical differences on VHL messenger RNA (mRNA) levels among simple, complex, and atypical hyperplasia (P < 0.01). The VHL mRNA levels in endometrial carcinoma were significantly lower than those in normal endometrium, simple hyperplasia, or complex hyperplasia (P < 0.01) but similar to those in atypical hyperplasia (P > 0.05). Von Hippel-Lindau protein levels by Western blotting and staining intensity by immunohistochemistry were coincident with the VHL mRNA levels. CONCLUSIONS: Aberrant expression of the VHL gene is associated with the risk of endometrial hyperplasia progressing to endometrial carcinoma, and its expression levels are useful as a predictive indicator for endometrial carcinoma.

[Human papillomavirus 16E6 gene mutation in cervical carcinoma tissues].

BACKGROUND AND OBJECTIVE: Human papillomavirus (HPV) 16 is the most common type of high-risk human HPVs. HPV16 E6 gene and its specific mutations are considered as risk factors causing cervical carcinoma (CC). This study was to investigate HPV16 E6 mutations in Lanzhou region and explore the relationship between HPV16 E6 mutations and the development of CC. METHODS: Tissue DNA was extracted from 23 patients operated on for CC and five normal cervical controls. The partial sequence of the HPV16 E6 gene (nucleotide 201-523) was amplified by PCR from the tissue DNA extracted from the samples. PCR fragments were sequenced and analyzed. RESULTS: The positive rates of HPV16 E6 in five normal cervical and 23 CC tissues were 0 (0/5) and 82.61% (19/23), respectively. Prototype HPV16E6 gene was found in six cases (33.33%) while mutation in the E6 gene was detected in 12 cases (66.67%), among which a 350G mutation was found in 11 cases (61.11%). Moreover, a 249G mutation was identified in one CC case (5.56%). CONCLUSIONS: There is a high HPV infection rate in CC tissues in Lanzhou region, and most of the HPV16E6 are mutated.

[Expression of centromere protein A in hepatocellular carcinoma].

OBJECTIVE: To study the expression of centromere protein A (CENP-A) and its significance in hepatocellular carcinoma (HCC) and adjacent non-neoplastic liver tissue. METHODS: The expression levels of CENP-A mRNA in 20 samples of HCC and adjacent non-neoplastic liver tissue were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and real-time quantitative polymerase chain reaction (qRT-PCR). Immunohistochemical study for CENP-A and p53 proteins was also performed on tissue microarrays containing 80 samples of HCC and adjacent liver tissue. RESULTS: The expression level of CENP-A mRNA in HCC (0.64 +/- 0.18) was higher than that in adjacent non-neoplastic liver tissue (0.09 +/- 0.09) (t = 12.78, P < 0.01). Of the 80 samples of HCC, 57 cases (71.25%) and 60 cases (75%) expressed CENP-A and p53 proteins respectively. The positivity rates of CENP-A and p53 proteins in non-neoplastic liver tissue were 43.75% (35/80) and 16.25% (13/80) respectively. There was a statistically significant difference in CENP-A and p53 protein expression between HCC and non-neoplastic liver tissue (P < 0.01). The coincident rate between CENP-A and p53 expression was 88.75% (71/80). Expression of CENP-A protein showed a positive correlation with that of p53 protein (r = 0.57, P < 0.01). CONCLUSION: The over-expression of CENP-A occurs at transcriptional level and may be related to malignant proliferation of HCC via possible interaction with p53 gene.

[Biological effects of COOH-terminal amino acid deletions of hepatitis B virus X protein on hepatocellular carcinoma cell line Huh7].

BACKGROUND & OBJECTIVE: The COOH-terminal amino acid deletions of hepatitis B virus X protein (HBx) commonly exist in human hepatocellular carcinoma (HCC). This study was designed to explore the biological effects of truncated HBx and wild type HBx on HCC cell line Huh7. METHODS: The mutants of HBx with 10, 20, 30, or 40 amino acids deletion at COOH-terminal (HBx3'-10, -20, -30, -40), or 37 amino acids deletion at the middle (HBx-XMR) were constructed. The recombinant truncated HBx and wild type HBx expression vectors were transfected into Huh7 cells. The integration of the exogenous vector DNA was detected by Neo gene polymerase chain reaction (PCR). The biological characteristics of positive clones were analyzed by MTT assay, colony formation assay, flow cytometry (FCM), and xenograft in nude mice. The expression of HBx3'-10, HBx3'-20, HBx3'-30, HBx3'-40, HBx-XMR and HBx was detected by immunohistochemistry. RESULTS: Huh7 cells grew faster in HBx3'-20 and HBx3'-40 groups than in HBx3'-30 group (P < 0.05). The colony formation rate was significantly higher in HBx3'-20 and HBx3'-40 groups than in HBx3'-30 and pcDNA3 groups [(17.34+/-2.77)% and (18.36+/-2.61)% vs. (7.31+/-1.44)% and (6.87+/-2.38)%, P < 0.05]. Compared with wild type HBx, HBx3'-20 and HBx3'-40 promoted more cells from G(1) phase into S phase in cell cycle [(36.96+/-1.82)% vs. (46.20+/-3.23)% and (53.99+/-4.02)% in S phase, P < 0.05], while HBx3'-10 and HBx3'-30 blocked the procedure in G(1) phase [(32.30+/-4.32)% and (30.34+/-1.47)% in S phase]; no obvious change was found between wide type HBx group and pcDNA3 group [(38.60+/-1.15)% in S phase]. The volume of xenograft tumor in nude mice was obviously larger in HBx3'-40 group than in HBx3'-30, wild type HBx, and pcDNA3 groups [(3.19+/-0.34) cm3 vs. (1.58+/-0.27) cm(3), (1.75+/-0.15) cm3, and (1.67+/-0.12) cm3]; the tumor weight showed the same trend among the groups. CONCLUSIONS: Compare with wide type HBx, HBx3'-20 and HBx3'-40 could promote the proliferation of Huh7 cells, but HBx3'-30 has the contrary effect. HBx mutants might play a role in the development of HCC through modifying the biological functions of HBx.

[Biological impact of the COOH-terminal 40 amino acid deletions of hepatitis B virus X protein in hepatocellular carcinoma cells].

OBJECTIVE: To investigate the biological impact of the wild type hepatitis B virus X protein (HBx) and HBx3'-40, an engineered deletion mutant of HBx lacking the last 40 C-terminal amino acids and a transcriptional transactivator on hepatoma cells. METHODS: Human hepatocellular cells of the lines Huh7 and SMMC-7721 were transfected with HBx3'-40 or HBx constructs. The integration of the plasmid DNA and the expression of HBx3'-40 and HBx were confirmed by Neo gene PCR and Western blotting respectively. The growth curves of different cells were obtained by MTT method. Plate clone formation test to calculate the clone formation rate. Flow cytometry (FCM), and Chloramphenicol acetyl transferase (CAT)-ELISA. Male BALB/c mice were divided into 3 groups to be inoculated subcutaneously with plasmids pcDNA3HBx, pcDNA3HBx3'-40, and blank plasmas pcDNA3 as controls. The mice were killed 15 and 30 days after and the tumors were taken out to undergo measurement and immunohistochemistry. RESULTS: Growth curve showed that after transfection the HBx3'-40 group cells grew faster than HBx and pcDNA3 transfected group cells. FCM analysis showed that HBx3'-40 transfection enhanced the progression of G(1) --> S phase in Huh7 cell cycle and HBx did not show such impact. The clone formation rates of pcDNA3HBx3'-40 group was 12.2% +/- 1.4%, significantly higher than those of the pcDNA3HBx, blank vector, and control groups (6.3% +/- 0.7%, 4.1% +/- 0.9%, and 6.1% +/- 1.1% respectively, all P < 0.05) in the Huh7 cells. The situation was the similar in the SMMC-7721 cells: 83% +/- 6% vs.49% +/- 8%, 27% +/- 3%, and 51% +/- 5% respectively (all P < 0.05). The apoptotic rates of SMMC-7721 cells under no serum condition transfected with HBx and HBx3'-40, especially the former, were 12.57% and 9.15%, significantly higher than that of the pcDNA3HBx group. The CAT expression of the pcDNA3HBx-transfected SMMC-7721 cells was 2.913 and 3.652 times those of the pcDNA3HBx3'-40 group and pcDNA3 group. The tumor weights of the mice inoculated with pcDNA3HBx3'-40, pcDNA3HBx, and blank vector-transfected Huh7 cells were 1.2 g +/- 0.17 g, 0.55 g +/- 0.12 g, and 0.48 g +/- 0.15 g respectively. The tumor weights of the mice inoculated with pcDNA3HBx3'-40, pcDNA3HBx, and blank vector-transfected SMMC-7721 cells showed similar features. CONCLUSION: HBx3'-40 protein significantly promote the proliferation of hepatocellular carcinoma cells and is involved in cell apoptosis and invasion, thus supporting the hypothesis that HBx mutants play a key role in hepatocarcinogenesis by modifying the biological functions of HBx. Besides, C-terminal mutants of HBx makes p53 tumor suppressor gene lose its cancerostatic function.

Immunocytochemical detection of HoxD9 and Pbx1 homeodomain protein expression in Chinese esophageal squamous cell carcinomas.

AIM: To evaluate the expression pattern of two novel oncofetal antigens, the HoxD9 and Pbx1 homeoproteins in esophageal squamous cell carcinomas (ESCCs) to determine what role they would play in the carcinogenesis of ESCC. METHODS: We obtained tissue samples of ESCC from 56 patients who underwent esophagectomy but not preoperative chemotherapy or radiotherapy. The diagnosis of ESCC was established and confirmed by staff pathologists. We used a highly sensitive, indirect, immunocytochemical method to detect HoxD9 and PbX1 proteins. We qualitatively and quantitatively evaluated cells that exhibited and staining using a light microscope. RESULTS: In all observed carcinoma tissue samples, more than 60% of neoplastic cells stained lightly or strongly for HoxD9, and more than 50% of neoplastic cells stained lightly or strongly for Pbx1. CONCLUSION: Our data suggest that HoxD9 and Pbx1 are inappropriately expressed in most human esophageal squamous cell carcinoma. Understanding the role of Hox genes in esophageal epithelial cell carcinogenesis may not only augment early detection but also offer new avenues for treatment of this disease.

[Effect of selenium dioxide on proliferation, apoptosis, and elomerase activity of human lung cancer cell line in vitro].

BACKGROUND & OBJECTIVE: It was reported that selenium could induce apoptosis of cancer cells; moreover, apoptosis of cancer cells and telomerase activity were closely related to the development of cancer. This study was designed to investigate the effect of selenium dioxide on human pulmonary adenocarcinoma GLC-82 cell to reveal its probable mechanism and the relationship between apoptosis and telomerase activity. METHODS: Methyl thiazolyl tetrazolium(MTT) method was used to determine the growth inhibition rates of lung cancer GLC-82 cells by various concentrations of selenium dioxide at different time. TRAP-PCR-ELISA assay was used to examine the changes of GLC-82 cells treated with selenium dioxide. The cell apoptotic rate was measured by flow cytometry (FCM). DNA ladder was showed by DNA agarose gel electrophoresis. The morphological changes of the cancer cells were examined under light and electron microscope. RESULTS: After being treated with 3, 10, 30 micromol/L selenium dioxide, the proliferation and telomerase activity of GLC-82 cells were markedly inhibited. The growth inhibition rates in GLC-82 cells for 24 hours were 0.7%, 12.8%, and 31.8%; for 72 hours were 15.1%, 51.2%, and 61.1%, respectively. Telomerase activity of GLC-82 cells for 24 hours were 1.173+/-0.029,1.127+/-0.067, and 1.050+/-0.098(P< 0.05); for 48 hours were 1.150+/-0.026, 1.047+/-0.060, and 0.950+/-0.036(P< 0.05), respectively (control group: 1.227+/-0.032 and 1.167+/-0.023, respectively). An apoptosis peak appeared before diploid peak in FCM. Agarose gel electrophoresis showed overt ladder-shape band of cell apoptosis. GLC-82 cells treated by selenium dioxide showed morphological characteristics of apoptotic cells. CONCLUSION: Selenium dioxide could significantly inhibit the growth of lung cancer GLC-82 cells through inducing apoptosis and inhibiting the telomerase activity. Selenium dioxide has strong growth inhibitory effect in a dose-and time-dependent manner.

[Effects of selenium dioxide on regulatory regions P250 of c-fos gene].

BACKGROUND & OBJECTIVE: This study was designed to investigate the impact of selenium dioxide (SeO2) on regulatory regions P250 of c-fos gene and to seek possible regulation mechanism. METHODS: HeLa cells were transfected with plasmids containing upstream regulating regions of c-fos chloramphenicol acetyl-transferase (CAT). The cells were cultured in various concentration of selenium dioxide. CAT expression in transfected cells was observed. RESULTS: After transfected HeLa cells were exposed to selenium dioxide, CAT expression showed obvious increase, especially in 10 micromol/L and 30 micromol/L selenium dioxide group (P< 0.05). CONCLUSION: Trough affecting regulatory regions P250 of c-fos gene, Selenium dioxide plays biological effect of regulating tumor cells. Selenium dioxide possibly has anti-tumor effects.

[Effect of electromagnetic pulse irradiation on mice reproduction].

OBJECTIVE: To evaluate the effect of electromagnetic pulse (EMP) irradiation on mice reproduction. METHODS: Female/male Kunming mice, 6 - 8 weeks old, prior to mating, or female after pregnancy were treated with whole body irradiation by 6 x 10(4) V/m electromagnetic pulse (EMP) for five times. The pregnant mice were killed on the 18th days, and teratological markers were analysed. RESULTS: EMP irradiation caused no significant changes in most of female organ weight and organ/body weight ratio. But it caused significant shortening in tail length of live foetus in the female mice before conception (prior to mating) or after pregnancy (P < 0.05), and obvious decrease in male offspring ratio (0.85 +/- 0.09 vs 1.09 +/- 0.17, P < 0.05). The male offspring ratio also significantly decreased (0.76 +/- 0.18 vs 1.09 +/- 0.17, P < 0.01) after male mice irradiated by EMP. The tail length of live foetus was shortened and male offspring sex ratio was increased after both male and female mice were irradiated by EMP. EMP irradiation also caused a significantly higher fetal death rate than normal control (P < 0.05). The embryo absorption rate was increased after irradiation except that was decreased in male mice. CONCLUSION: EMP irradiation has effect on pregnancy and offspring development in both male and female mice before mating and in female mice after pregnancy.

[Apoptosis of human lung carcinoma cell line GLC-82 induced by high power electromagnetic pulse].

BACKGROUND & OBJECTIVE: Electromagnetic pulse (EMP) could be used for sterilization of food and the efficiency is higher than 2450 MHz continuous microwave done. This study was designed to evaluate the effect of electromagnetic pulse (EMP) on apoptosis of human lung carcinoma cell line GLC-82, so that to explore and develop therapeutic means for cancer. METHODS: The injury changes in GLC-82 cells after irradiated with EMP (electric field intensity was 60 kV/m, 5 pulses/2 min) were analyzed by cytometry, MTT chronometry, and flow cytometry. The immunohistochemical SP staining was used to determine the expressions of bcl-2 protein and p53 protein. The stained positive cells were analyzed by CMIAS-II image analysis system at a magnification 400. All data were analyzed by SPSS8.0 software. RESULTS: EMP could obviously inhibited proliferation and activity of lung carcinoma cell line GLC-82. The absorbance value (A570) of MTT decreased immediately, at 0 h, 1 h, and 6 h after the GLC-82 cells irradiated by EMP as compared with control group. The highest apoptosis rate was found to reach 13.38% by flow cytometry at 6 h after EMP irradiation. Down-regulation of bcl-2 expression and up-regulation of p53 expression were induced by EMP. CONCLUSION: EMP promotes apoptosis of GLC-82 cells. At same time, EMP can down-regulate bcl-2 expression and up-regulate p53 expression in GLC-82 cells. The bcl-2 and the p53 protein may involve the apoptotic process.

[Expression of p53 and vascular endothelial growth factor in esophageal squamous cell carcinoma and their clinical significance].

BACKGROUND & OBJECTIVE: Experimental study proved that the coexpression of p53 and vascular endothelial growth factor (VEGF) play an important role in angiogenesis of tumor. The aim of this study was to investigate the mechanism that p53 participate angiogenesis and the relationship between the expression of p53 and VEGF and clinical pathologic parameters and prognosis of esophageal squamous cell carcinoma (ESCC). METHODS: The expressions of p53 and VEGF in operative samples from 76 ESCC patients were detected by immunohistochemistry. The vascular endothelial cells in tumor tissue were labeled by F VIII factor antibody for counting microvessel density (MVD). RESULTS: The expression rates of p53 and VEGF were 60.5% and 56.5%; total expression rate was 42.1%. The expression rates of p53 and VEGF were strongly associated with distal metastasis and vascular infiltration of ESCC (P < 0.05, P < 0.01). Distal metastasis and vascular infiltration usually occurred in the patients whose mutant p53 and VEGF were both positive expression. The MVDs in p53(+) or VEGF(+) (31.7 +/- 11.5; 33.8 +/- 11.7) were both significantly higher than that in p53(-) or VEGF(-) (22.4 +/- 10.6; 21.2 +/- 9.3, P < 0.05). The MVD reached the maximum in the patients whose p53 and VEGF were both positive. CONCLUSION: Mutant p53 expression is closely associated with the angiogenesis and distal metastasis of ESCC; Expression of p53 and VEGF could be used as an important biological indices for evaluating the malignant degree of ESCC. Combined determination of p53 and VEGF expression has important clinical significance.