Reduced expression of annexin A1 promotes gemcitabine and 5-fluorouracil drug resistance of human pancreatic cancer.

Intrinsic chemoresistance is the main reason for the failure of human pancreatic ductal adenocarcinoma (PDAC) therapy. To identify the candidate protein, we compared the protein expression profiling of PDAC cells and its distinct surviving cells following primary treatment with gemcitabine (GEM) and 5-fluorouracil (5-FU) by two-dimensional electrophoresis combined with liquid chromatography-mass spectrometry or mass spectrometry. A total of 20 differentially expressed proteins were identified, and annexin A1 (ANXA1) was analyzed for further validation. The functional validation showed that the downregulation of ANXA1 contributes to GEM and 5-FU resistance in PDAC cells through protein kinase C/c-Jun N-terminal kinase/P-glycoprotein signaling pathway. Our findings provide a platform for the further elucidation of the underlying mechanisms of PDAC intrinsic chemoresistance and demonstrated that ANXA1 may be a valid marker for anticancer drug development.

MAP4K4 promotes epithelial-mesenchymal transition and metastasis in hepatocellular carcinoma.

Our previous study has reported that mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4) regulates the growth and survival of hepatocellular carcinoma (HCC) cells. This study was undertaken to explore the roles of MAP4K4 in the epithelial-mesenchymal transition (EMT) and metastasis in HCC. Effects of overexpression and knockdown of MAP4K4 on the migration, invasion, and EMT of HCC cells were examined. The in vivo role of MAP4K4 in lung metastasis of HCC was determined in nude mice. The relationship between MAP4K4 expression and EMT in human HCC specimens was determined by immunohistochemistry. MAP4K4 overexpression significantly enhanced the migration and invasion of MHCC-97L HCC cells, whereas MAP4K4 silencing hindered the migration and invasion of MHCC-97H HCC cells. MAP4K4-overexpressing cells undergo EMT, which was accompanied by downregulation of E-cadherin and upregulation of vimentin. In contrast, MAP4K4 silencing caused a reversion from a spindle morphology to cobblestone-like morphology and induction of E-cadherin and reduction of vimentin. Pretreatment with chemical inhibitors of JNK and NF-κB abolished MAP4K4-mediated migration, invasion, and regulation of EMT markers in MHCC-97L cells. Ectopic expression of MAP4K4 promoted and knockdown of MAP4K4 inhibited lung metastasis of HCC, which was associated with regulation of JNK and NF-κB signaling and EMT markers. High MAP4K4 immunoreactivity was inversely correlated with E-cadherin and was positively correlated with vimentin, phospho-JNK, and phospho-NF-κB in HCC specimens. Taken together, MAP4K4 promotes the EMT and invasiveness of HCC cells largely via activation of JNK and NF-κB signaling.

Study on the High-Temperature Interaction between Coke and Iron Ores with Different Layer Thicknesses.

Coke plays a key role as the skeleton of the charge column in BF. The gas path formed by the coke layer in the BF has a decisive influence on gas permeability. At high temperatures, the interface between coke and ore undergoes a melting reaction of coke and a reduction reaction of ore. The better the reducibility of the ore, the more conducive it is to the coupling reaction of ore and coke. The melting loss reaction of coke becomes more intense, and the corresponding strength of coke will decrease, which will affect the permeability of the blast furnace and is not conducive to the smooth operation of the blast furnace. Especially with a deterioration in iron ore quality, BF operation faces severe challenges, which makes it necessary to find an effective way to strengthen BF operation. In this study, a melting-dropping furnace was used to develop and clarify the high-temperature interaction between coke and iron ores with different layer thicknesses. The influencing factors were studied by establishing a gas permeability mathematical model and observing the metallographic microscope images of samples after the coke solution loss reaction. The relationships between coke layer thickness, distribution of gas flow, and pressure drop were obtained. The results showed that, under certain conditions, the gas permeability property of a furnace burden has been improved after the coke layer thickness increased. Upon observing the size of coke particles at the interface reaction site, the degree of melting loss reaction can be determined. A smaller particle size indicates more melting loss reaction. A dripping eigenvalue for molten metal was introduced to evaluate the dynamic changes in the comprehensive dripping properties of molten metal of furnace burden, which showed that the dripping eigenvalue for the molten metal could deteriorate because of the unruly thickness and the coke layer thickness should be limited through considering the operational indicators of the blast furnace.

SiRNA-targeted carboxypeptidase D inhibits hepatocellular carcinoma growth.

Carboxypeptidase D (CPD), a membrane-bound metallocarboxypeptidase that functions as a docking receptor for duck hepatitis B virus, is frequently overexpressed in human cancers. We have explored its expression pattern, clinical significance, and biological function of CPD in hepatocellular carcinoma (HCC). CPD expression was markedly elevated in HCCs relative to adjacent non-tumor liver tissues, as determined by quantitative real-time polymerase chain reaction and Western blot analysis. Immunohistochemistry showed that 164 of 400 (41%) HCCs had high expression of CPD. CPD overexpression was significantly associated with serum levels of hepatitis B surface antigen and hepatitis B e antigen, liver cirrhosis, pathological grade, and intrahepatic metastasis. Knockdown of endogenous CPD expression in Huh7 HCC cells by RNA interference reduced cell proliferation, blocked the cell cycle at G1 phase, and increased apoptosis. Many genes implicated in cell-cycle regulation, including P21waf1, P27 Kip1, SKP2, and CDC2, were deregulated by CPD downregulation. Thus CPD is frequently upregulated in HCC, and targeting CPD inhibits HCC cell proliferation through induction of G1 cell-cycle arrest and apoptosis, thereby providing a potential therapeutic target for this malignancy.

[Clinicopathologic characteristics of fibrous mass-forming chronic pancreatitis].

OBJECTIVE: To investigate clinicopathological features of fibrous mass-forming chronic pancreatitis (FMCP), to compare clinicopathological and immunohistochemical characteristics between autoimmune pancreatitis (AIP) and fibrous mass-forming non-autoimmune pancreatitis (nAIP) and to provide evidence for pathological diagnosis, differential diagnosis and clinical treatment strategy. METHODS: Clinicopathological features were analyzed in 81 cases of FMCP. Infiltrating IgG4(+) plasmacytes were counted by immunohistochemical staining. RESULTS: Among 81 cases of FMCP, 20 cases were diagnosed as AIP and 61 cases were interpreted as nAIP. AIP was more common in males over 50 years, whereas nAIP was seen in much younger patients (P = 0.001). The amount of inflammatory cells in the stroma of AIPs was remarkable higher than that in nAIPs (P = 0.002). The incidence of neuritis in AIPs (100%, 20/20) was also higher compared with that of nAIPs (75.4%, 46/61; P = 0.017). Storiformed-fibrosis was more common in AIPs (95.0%, 19/20) than in nAIPs (1.6%, 1/61;P = 0.000). Pancreatic intraepithelial neoplasia (PanIN) was observed in 50.0%(10/20) of AIPs and 32.8%(20/61) of nAIPs, with a greater severity observed in AIPs (P = 0.031). Tubular complex (TC) was more commonly observed in AIPs (65.0%, 13/20) than nAIPs (26.2%, 16/61;P = 0.002). Among 81 cases of FMCP, 61 cases had less than 11 IgG4(+) plasmacytes /HPF, 7 cases had 10-30/HPF and 13 cases had over 30/HPF. CONCLUSIONS: FMCPs include both AIP and nAIP. AIP has distinct pathological features and the presence of IgG4(+) plasmacyte is an important diagnostic parameter. FMCP appears to be an important precancerous lesion of pancreatic ductal adenocarcinoma. Surgery may be considered for patients with FMCP due to its mass-forming nature. In contrast, patients with AIP are treated medically due to its steroid-responsiveness. Therefore, accurate and timely diagnosis of AIP is of clinical relevance to avoid unnecessary surgical complications and to prevent progression of the disease.

[Expression and significance of neurogenic differentiation protein in pancreatic carcinoma].

OBJECTIVE: To investigate the expression and significance of neurogenic differentiation protein (NeuroD) in pancreatic carcinoma. METHODS: The expression of NeuroD, PCNA and p53 proteins in 127 specimens of pancreatic carcinoma was detected by tissue microarray and immunohistochemestry. The correlations were analyzed between NeuroD and PCNA, p53, neural invasion, sleeve-like lymphocytic infiltration around the nerve, pancreatitis adjacent to carcinoma, lymph node metastasis and age, gender, location of tumors, histological types and differentiation of pancreatic carcinomas. RESULTS: The positive rates of NeuroD, PCNA and p53 expression were higher in pancreatic carcinoma than those in non-tumor pancreatic tissues [64.6% (82/127) vs 10.5% (8/76), 57.5% (73/127) vs 9.2% (7/76), 59.1% (75/127) vs 9.2% (7/76), P < 0.01]. NeuroD expression in pancreatic carcinoma was related to that of PCNA and p53 and neural invasion (P < 0.05). No significant correlation was found between NeuroD and age, gender, tumor location, histological types and differentiation, sleeve-like lymphocytic infiltration, pancreatitis adjacent to the carcinoma and lymph node metastasis in pancreatic carcinomas. CONCLUSIONS: NeuroD overexpression in pancreatic carcinoma. The overexpression of NeuroD may contribute to the tumorogenesis and development of pancreatic carcinoma, and is closely correlated to the cancer cell proliferation, p53 signal pathway and neural invasion in pancreatic carcinoma.

[Detection of human telomerase RNA component gene by fluorescent in situ hybridization for screening of cervical lesions].

OBJECTIVE: To investigate the value of fluorescence in situ hybridization (FISH) detection of human telomerase RNA component (hTERC) gene amplification in screening of cervical lesions. METHODS: A total of 146 post-thinPrep cytology test (TCT) samples were analyzed using FISH by two-color interphase probe targeting hTERC gene at chromosome 3q26 and the data were compared with the cytological and histological results. RESULTS: FISH analysis was successful in 120 cases (20 cases of normal and 100 abnormal cases by TCT). Gene amplification of hTERC by FISH had a positive correlation with the cytological (r = 0.465, P < 0.01) and histological grade results (r = 0.610, P < 0.01). Extra copies of hTERC were seen in 28.6% (6/21) of CINI, 61.1% (11/18) of CINII, 75.0% (18/24) of CINIII and 91.7%(22/24) of squamous cell carcinoma, respectively. None (0/13) of the inflammation cases showed hTERC amplification. The sensitivity and specificity for detecting high grade lesions by FISH were 77.3% (51/66) and 82.4% (28/34); and the positive and negative predictive values were 89.5% and 65.1%, respectively. The rate of hTERC gene gain in high grade lesions was significantly higher than that in the low grade lesions (χ(2) = 32.550, P < 0.01). Combined with the high copy numbers, the sensitivity for detecting high grade lesions was increased to 81.2%. CONCLUSIONS: Detection of hTERC gene amplification by FISH improves the screening efficiency of high-risk cervical epithelial lesions. The presence of high copy numbers of hTERC correlates with the presence of high grade cervical dysplasia.

Rupture of splenic artery aneurysm in pregnancy: a review of the literature and report of two cases.

BACKGROUND: Splenic artery aneurysms are an uncommon form of vascular disease, which have a significant potential for rupture, most commonly associated with pregnancy, typically presents as sudden, unexpected death. As a consequence, the initial recognition and diagnosis of splenic artery aneurysm rupture take place only at autopsy. CLINICAL CASES: This report presents 2 cases of sudden death resulting from splenic artery aneurysm in a pregnant woman and a postpartum woman, respectively. The former splenic artery aneurysm were measuring 1 cm in diameter and the latter splenic artery aneurysm 5.5 x 5 x 2 cm in size. Histologic examination of the both vessels wall showed severe morphologic changes of degeneration together with an attenuation of arterial internal elastica. CONCLUSIONS: To our knowledge, splenic artery aneurysm in pregnant woman is unusual vital disease. It is essential that obstetricians are alert to the prodromal and catastrophic symptoms of splenic artery aneurysm. Early recognition and prompt management, including early resected electively, are vital to the survival of both mother and fetus.

Comparing prognostic values of the 7th and 8th editions of the American Joint Committee on Cancer TNM staging system for gastric cancer.

BACKGROUND AND AIM: Our aim was to compare the prognostic value of the American Joint Committee on Cancer (AJCC) 7th and 8th editions staging systems for patients with gastric cancer in China. METHODS: A total of 1326 gastric cancer patients diagnosed between 2008 and 2012 were included. The discriminative ability of the AJCC 8th and 7th editions was compared using the Harrell's concordance index (C-index). RESULTS: There are two main modifications in the 8th edition. (i) pN3 staging was divided into pN3a and pN3b. The gastric cancer patients with pN3a experienced significantly better overall survival compared with those with pN3b (5-year overall survival: 34.5% vs. 15.6%, P < 0.001) (stratified by pT: pT3: 5-year overall survival: 33.9% vs. 13.2%, P < 0.001; pT4a: 32.8% vs. 16.9%, P = 0.056; pT4b: 17.0% vs. 11.1%, P = 0.048). (ii) Subgroup staging adjustments. The subgroup staging adjustments (T3N3bM0 (IIIB→IIIC), T4aN3aM0 (IIIC→IIIB), T4bN0M0 (IIIB→IIIA), and T4bN2M0 (IIIC→IIIB)) resulted in more gastric cancer patients being accurately staged. Furthermore, the C-index value of the 8th edition tumor node metastasis (TNM) staging system was significantly higher than that of the AJCC 7th TNM staging system to predict the survival of gastric cancer patients (0.701 vs. 0.685, P < 0.001). CONCLUSIONS: The 8th edition of the TNM staging system is superior to the 7th edition staging system for prediction of survival of gastric cancer patients in China.

Oncoprotein BMI-1 induces the malignant transformation of HaCaT cells.

BMI-1 (B-cell-specific Moloney murine leukemia virus integration site 1), a novel oncogene, has attracted much attention in recent years for its involvement in the initiation of a variety of tumors. Recent evidence showed that BMI-1 was highly expressed in neoplastic skin lesions. However, whether dysregulated BMI-1 expression is causal for the transformation of skin cells remains unknown. In this study, we stably expressed BMI-1 in a human keratinocyte cell line, HaCaT. The expression of wild-type BMI-1 induced the malignant transformation of HaCaT cells in vitro. More importantly, we found that expression of BMI-1 promoted formation of squamous cell carcinomas in vivo. Furthermore, we showed that BMI-1 expression led to the downregulation of tumor suppressors, such as p16INK4a and p14ARF, cell adhesion molecules, such as E-Cadherin, and differentiation related factor, such as KRT6. Therefore, our findings demonstrated that dysregulated BMI-1 could indeed lead to keratinocytes transformation and tumorigenesis, potentially through promoting cell cycle progression and increasing cell mobility.

[Endoscopic retrograde cholangiopancreatography-guided brush cytology diagnosis of pancreatobiliary tumors].

OBJECTIVE: To study the cytologic features of pancreatobiliary tumors in endoscopic retrograde cholangiopancreatography (ERCP)-guided brushing preparations and to evaluate the usefulness of cytology in the diagnosis of pancreatobiliary malignancy. METHODS: A retrospective analysis of 212 cases of ERCP-guided brush cytology smears performed during the period from January, 2004 to December, 2006. The cytologic diagnosis was confirmed either by the histologic diagnosis or the strict clinical criteria. RESULTS: Two of the cases studied were unsatisfactory for diagnosis, with no epithelial cells identified. One hundred and thirty-seven smears were diagnosed as "negative", 45 of which subsequently confirmed to be malignant (negative predictive value = 60.2%). Six of the 11 cases with "low-grade atypia" were proven to be malignant (positive predictive value = 54.5%), as compared to 19 of 23 cases of "high-grade atypia" (positive predictive value = 86.4%). All of the 41 cases with cytologic diagnosis of "malignancy" were confirmed to be malignant (positive predictive value = 100%). The cytologic features of malignancy in ERCP-guided brushing preparations included overlapping nuclei, anisonucleosis, coarse chromatin pattern, poor cellular cohesion, tumor diathesis, prominent nucleoli and atypical mitotic figures. CONCLUSIONS: The accuracy of ERCP-guided brush cytology relies on good specimen preparation and application of morphologic criteria. Grading of cytologic atypia is of clinical significance. A "negative" or "low-grade atypia" cytologic diagnosis requires further diagnostic workup to rule out the possibility of underlying malignancy, while a "high-grade atypia" or "malignant" diagnosis is relatively specific in guiding subsequent management of suspected pancreatobiliary malignancy.

[Solitary plasmacytoma of spine: a clinical, radiologic and pathologic study of 13 cases].

OBJECTIVE: To study the clinical, radiologic and pathologic features of solitary plasmacytoma of spine. METHODS: The clinical, radiologic and pathologic features, as well as treatment and follow-up data, of 13 solitary plasmacytoma of spine cases were retrieved and analyzed. Immunohistochemical study using EnVision method for LCA, CD19, CD20, CD79a, CD3, CD7, PC, MUM1, CD138, IgG, IgM, kappa, lambda and Ki-67 was carried out. RESULTS: All the tumours were primarily located in the vertebrae (including 9 cases in thoracic vertebrae and 4 cases in lumbar vertebrae). The male-to-female ratio was 3.3:1. The age of the patients ranged from 42 to 69 years (mean age = 56 years). The commonest symptom was pain in the surrounding regions. The degree of neurologic disturbance mostly depended on the extent of vertebral destruction and structural instability of the spine. Radiologic examination showed mainly osteolytic lesions in vertebrae. Magnetic resonance imaging demonstrated the presence of heterogeneous intensity inside the involved vertebrae (low in T1 weighted and high in T2 weighted images). Histologic examination showed diffuse infiltration by malignant cells. In well-differentiated plasmacytomas, the tumor cells resembled normal plasma cells. In poorly differentiated examples, the cellular morphology mimicked that of the centroblasts. The interstitial stroma was scanty and contained plenty of vessels, sometimes with formation of blood lakes. Amyloid deposition was present in some of the cases. Immunohistochemical study showed that the tumor cells were positive for CD79a and negative for CD20. Light chain restriction was detected in all the 13 cases studied. Plasma cell marker PC was expressed in all cases, while IgG was positive in 5 cases, IgM in 1 case, MUM1 in 10 cases and CD138 in 8 cases. Ki-67 index varied from 10% to 50%. All cases were operated, with adjuvant chemotherapy and radiotherapy given. CONCLUSIONS: Correlation of clinical, radiologic and pathologic features is important in diagnosis of solitary plasmacytoma of spine. The possibility of multiple myeloma needs to be excluded. Early detection by radiologic examination, local surgical resection, post-operative chemoradiotherapy and long-term follow-up are prudent for successful management of this condition.

Prognostic Value of the Number of Lymph Nodes Examined in Patients with Node-Negative Gastric Cancer.

BACKGROUND: Our aim was to evaluate the prognostic value of the number of lymph nodes examined (eLNs) in patients with node-negative gastric cancer (GC) and further to adjust the American Joint Committee on Cancer (AJCC) 8th staging system based on the number of eLNs. METHODS: Node-negative GC patients diagnosed during 1988-2015 from the Surveillance, Epidemiology, and End Results (SEER) database were included. On the basis of a primary cohort of 4159 node-negative GC patients, we built the adjusted AJCC 8th staging system, which was then internally validated by a bootstrap method, and externally validated with an independent cohort of 5565 node-negative GC patients. RESULTS: The median number of eLNs was 10. For the training set, the optimal eLNs thresholds were determined to be 9 for node-negative GC patients. The adjusted AJCC 8th staging system for node-negative GC patients based on the number of eLNs had a significantly higher Harrell's concordance index than the initial AJCC 8th staging system (C-index, 0.635 versus 0.616; P < 0.001). Thus, the adjusted AJCC 8th staging system had superior prognostic stratification. Similar results were found in the validation set. CONCLUSIONS: For node-negative GC patients in the United States, the adjusted AJCC 8th staging system based on the number of eLNs predicted survival more accurately and discriminatively.

Modified American Joint Committee on Cancer Tumor-Node-Metastasis Staging System Based on the Node Ratio Can Further Improve the Capacity of Prognosis Assessment for Gastric Cancer Patients.

Background and Objectives: Our aim was to investigate whether the modified American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) staging system based on the node ratio can further improve the capacity of prognosis assessment for gastric cancer (GC) patients regardless of the number of lymph nodes examined (eLNs). Methods: A total of 17,187 GC patients in the Surveillance, Epidemiology, and End Results (SEER) database were included. On the basis of a training set of 7,660 GC patients, we built the tumor-node ratio-metastasis (TNrM) staging system, which was then externally validated with a validation set of 9,527 GC patients. Results: For the training set, the C-index value of the TNrM staging system was significantly higher than that of the AJCC 8th TNM staging system to predict survival for GC patients (C-index: 0.688 vs. 0.671, P < 0.001). Moreover, the C-index value of the TNrM staging system was significantly higher than that of the 8th TNM staging system to predict survival for GC patients with ≤15 eLNs (C-index: 0.682 vs. 0.673, P < 0.001), as well as for GC patients with >15 eLNs (C-index: 0.700 vs. 0.694, P < 0.001). Similar results were found in the validation set. Conclusions: The TNrM staging system predicted survival more accurately and discriminatively than the AJCC 8th TNM staging system for GC patients regardless of the number of eLNs.

MicroRNA-6809-5p mediates luteolin-induced anticancer effects against hepatoma by targeting flotillin 1.

BACKGROUND: Luteolin (3,4,5,7-tetrahydroxy flavone) is a natural flavonoid abundant in fruits and vegetables. Although luteolin has shown pro-apoptotic activity in hepatocellular carcinoma (HCC) cells, the underlying molecular mechanism has not yet been clarified. PURPOSE: The aim of this study is to identify novel miRNAs involved in the action of luteolin in HCC cells and to explore the biological roles of these miRNAs. METHODS: The effect of luteolin on HCC cell growth was assessed using CCK-8 colony formation assay, flow cytometric analysis in vitro, and a xenograft model in vivo. miRNA expression profiles were assessed using next-generation sequencing. Differentially expressed miRNAs were validated by quantitative PCR. Bioinformatics analysis and luciferase reporter assay were utilized to confirm the binding of miR-6809-5p to the 3'-untranslated region (3'-UTR) of flotillin 1 (FLOT1). Furthermore, the effects of ectopic FLOT1 and miR-6809-5 expression on cell proliferation, colony formation, and cell apoptosis were also assessed. Western blotting analysis was used to detect activation of multiple signaling molecules including Erk1/2, p38, JNK, and NF-κB/p65 in the MAPK pathway. RESULTS: It was found that luteolin significantly inhibited HCC growth and caused apoptosis and cell cycle arrest at the G0/G1 phase in Huh7 cells, at the G2/M phase in HepG2 cells in vitro. Tumorigenic studies revealed that luteolin treatment significantly suppressed HCC growth in vivo. miR-6809-5p was upregulated by luteolin. Overexpression of miR-6809-5p suppressed HCC cell growth, while knockdown of miR-6809-5p reversed the anticancer effect of luteolin. With regards to its signaling mechanism, miR-6809-5p directly targets FLOT1in HCC cells. Enforced expression of FLOT1 prevented miR-6809-5p-mediated growth suppression. Downregulation of FLOT1 exerted growth-suppressive effects on HCC cells. Multiple signaling pathways including Erk1/2, p38, JNK, and NF-κB/p65 were inactivated by miR-6809-5p overexpression or FLOT1 downregulation. CONCLUSION: These findings indicated that miR-6809-5p mediates the growth-suppressive activity of luteolin in HCC, which is causally linked to FLOT1 downregulation. Induction of miR-6809-5p may provide therapeutic benefits in the treatment of HCC.

Primary lymphoblastic B-cell lymphoma of the stomach: a case report.

Primary stomach lymphoblastic B-cell lymphoma (B-LBL) is a rare tumor. We describe a primary stomach B-LBL in a 38 years old female who presented with nonspecific complaints of fatigue and vomiting for 2 mo. Gastrofiberscopy revealed a large gastric ulcer, which was successfully resected. Pathology showed a lymphoblastic cell lymphoma arising from the stomach, and there was no evidence of disease at any extrastomach site. Immunohistochemical staining and gene rearrangement studies supported that the stomach tumor was a clonal B-cell lymphoma. Therefore, the diagnosis of B-LBL was made based on the stomach specimen.

COOH-terminal deletion of HBx gene is a frequent event in HBV-associated hepatocellular carcinoma.

AIM: To investigate the hepatitis B virus (HBV)x gene (HBx) state in the tissues of HBV-related hepatocellular carcinoma (HCC) in Chinese patients and whether there were particular HBx mutations. METHODS: HBx gene was amplified and direct sequencing was used in genomic DNA samples from 20 HCC and corresponding non-cancerous liver tissues from HBsAg-positive patients. HBV DNA integration and HBx deleted mutation were validated in 45 HCC patients at different stages by Southern blot analysis and polymerase chain reaction methods. RESULTS: The frequencies of HBx point mutations were significantly lower in HCC than their corresponding non-cancerous liver tissues (11/19 vs 18/19, P=0.019). In contrast, deletions in HBx gene were significantly higher in HCC than their non-cancerous liver tissues (16/19 vs 4/19, P<0.001). The deletion of HBx COOH-terminal was detected in 14 HCC tissues. A specific integration of HBx at 17p13 locus was also found in 8 of 16 HCC, and all of them also exhibited full-length HBx deletions. Integrated or integrated coexistence with replicated pattern was obtained in 45.5% (20/45)-56.8% (25/45) tumors and 40.9% (18/45)-52.3% (23/45) non-tumor tissues. CONCLUSION: HBx deletion, especially the COOH-terminal deletion of HBx is a frequent event in HBV-associated HCC tissues in China. HBV integration had also taken place in partial HCC tissues. This supporting the hypothesis that deletion and probably integrated forms of the HBx gene may be implicated in liver carcinogenesis.

[Effect of siRNA targeting centromere protein-A gene on biological behavior of HepG2 cells].

OBJECTIVE: To study the influence of siRNA inhibition of CENP-A expression on the biological behavior of HepG2 cells. METHODS: Three pairs of 21 bp reverse repeated motifs of CENP-A target sequence with 9 spacer were synthesized and inserted into vector pSilencer 2.1-U6 neo to generate siRNA eukaryotic expression plasmids. After stable transfection into HepG2 cells, cell growth, apoptosis, cell cycles and plate clone forming efficiency were investigated. Expressions of CENP-A mRNA was monitored by the reverse transcriptase polymerase chain reaction (RT-PCR). The protein expression of CENP-A, bcl-2, Bax, p53, p21waf1 and mdm2 were detected by Western-blotting. RESULTS: Two eukaryotic expression plasmids with significant siRNA specific inhibition to the CENP-A gene were created. Compared with control cells, HepG2 cells transfected with the constructs showed G1 phase delay (P < 0.01) and cell number decrease in the S phase (P < 0.001), along with an increased apoptotic rate (P = 0.003), significant increase of Bax expression and decreased bcl-2 expression (P< or =0.001). The protein expressions of p21waf1 was higher and mdm2 was lower than those of the control groups. However, the wild type p53 protein expression was not effected by CENP-A siRNA. CONCLUSIONS: An altered expression of CENP-A may be related to the proliferation of hepatocellular carcinoma through cell cycle regulation involving an altered bcl-2/Bax expression, that may be p53 independent.

[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.