Shengquan Zou

Expression of P-aPKC-ι, E-Cadherin, and β-Catenin Related to Invasion and Metastasis in Hepatocellular Carcinoma

ObjectivesAtypical protein kinase C iota (aPKC-ι) and its associated intracellular molecules, E-cadherin and β-catenin, are important for cell polarization in tumorigenesis and progression. Expression of aPKC-ι, P-aPKC-ι (activated aPKC-ι), E-cadherin, and β-catenin in hepatocellular carcinoma (HCC) was measured, and correlation with clinicopathological characteristics of HCC was analyzed.MethodsParaffin-embedded tumor tissue was obtained from patients with HCC after resection without preoperative radiotherapy or chemotherapy. Gene expression was detected by polymerase chain reaction (PCR), and protein expression was detected by immunohistochemistry and Western blot analysis. Expressions of aPKC-ι, P-aPKC-ι, E-cadherin, and β-catenin were analyzed with relation to the clinicopathological data.ResultsThe gene and protein expression of aPKC-ι are obviously higher in HCC tissues than that in peritumoral tissues and normal tissues by semiquantitative PCR and immunohistochemistry methods. Accumulation of aPKC-ι in HCC cytoplasm and nucleolus inhibited the later formation of belt-like adherens junctions (AJs) and/or tight junctions (TJs) in cell–cell contact. E-cadherin was reduced and accumulation of cytoplasm β-catenin was increased in HCC. The expression of aPKC-ι was closely related to pathological differentiation, tumor size, invasion, and metastasis of HCC.ConclusionAccumulation of cytoplasm aPKC-ι may reflect pathological differentiation, invasion, and metastasis potential of HCC. In this regard, our study on HCC revealed the potential usefulness of aPKC-ι, E-cadherin, and β-catenin as a prognostic marker, closely related to pathological differentiation, invasion, metastasis, and prognosis of HCC.

Methyl-CpG binding protein MBD2 is implicated in methylation-mediated suppression of miR-373 in hilar cholangiocarcinoma.

Aberrant expression of miRNAs is associated with particular cancers showing tissue- and clinical-feature-specificity patterns. Some miRNA genes harboring or being embedded in CpG islands undergo methylation mediated silencing. MBP, methyl CpG binding protein, suppresses transcription through binding to methylated CpG dinucleotides. Expression of miR-373 has been reported to be suppressed in malignant bile duct cell lines. Bioinformatic prediction reveals that the transcription start site (TSS) of miR-373 is implanted in a 402 bp canonical CpG island containing 26 CpG dinucleotides. In this study, we aim to determine the epigenetic regulation of miR-373 gene in hilar cholangiocarcinoma. Taqman microRNA assay shows that down-regulation of miR-373 is closely associated with poor cell differentiation, advanced clinical stage and shorter overall and disease-free survival in hilar cholangiocarcinomas. Methylation analysis shows that the promoter-associated CpG island is hypermethylated which is consistent with the inhibition of miR-373. Chromatin immunoprecipitation (ChIP) assay indicates that down-regulation of miR-373 results from the selective recruitment of MBD2 to methylated CpG islands. In contrast, MBD2 knock-down by use of a specific siRNA promoted the expression of miR-373. Reactivation of miR-373 by pharmacologic induction of 5-aza-CdR and trichostatin A (TSA) led to decreased enrichment of MBD2 at CpG island regions. Enhanced expression of exogenous MBD2 in stable QBC939 cells which stably express pGL4-m373-prom induces strengthened recruitment of MBD2. Our findings suggest that miR-373 is a methylation-mediated gene and the implication of MBD2 in methylation-mediated suppression of miR-373 plays an important role in tumourigenesis and development in hilar cholangiocarcinoma.

Significance and Expression of Atypical Protein Kinase C-ɩ in Human Hepatocellular Carcinoma

BACKGROUND AND OBJECTIVE Previous studies have indicated that abnormal expression of atypical protein kinase C (aPKC-iota) plays a critical role in occurrence and progression of malignant tumor. This study analyzed the correlation of aPKC-iota with clinicopathology in hepatocarcinoma and Cyclin E and investigated molecular mechanisms of invasion and metastasis of hepatocellular carcinoma. MATERIALS AND METHODS The expression of the aPKC-iota gene was examined by reverse transcription-polymerase chain reaction in 7 specimens of normal liver tissues and 43 of hepatoma and adjacent tissues. Expression of aPKC-iota and Cyclin E protein was detected using immunohistochemistry and Western blot. Finally, we analyzed the correlation of aPKC-iota with clinicopathologic characteristics and invasion of hepatoma. RESULTS The expression value (0.844 +/- 0.315) of aPKC-iota gene is obviously higher in hepatoma than the value (0.530 +/- 0.217) in adjacent tissues and the value (0.372 +/- 0.130) in normal tissue (P = 0.009). The positive expression rate (58.1%) of aPKC-iota protein in hepatoma is remarkably higher than the rate (23.3%) of adjacent tissues. The expression of aPKC-iota has a positive correlation with the expression of Cyclin E, differentiation degree, and invasion of tumor (P < 0.05). CONCLUSIONS Differentiation degree and invasion of hepatoma are related to the expression of aPKC-iota, which plays an important role in invasion and metastasis of hepatoma.

Co-Ni-W-P Magnetic Films Electrolessly Deposited on Nitinol and the Application in Magnetically Targeted Therapy

Co-Ni-W-P magnetic films were electrolessly deposited on the nitinol wires. Their composition, microstructure, and magnetic properties were characterized by EDS, FESEM, and VSM. Their application in magnetically targeted therapy was investigated on animals. It was found that their composition and surface morphology can be controlled by the bath pH which can strongly influence the Hc, Mr, and BHmax. The magnetic nitinol wires with the Co-Ni-W-P films, combining with the magnetic nanoparticles containing 5-FU, were confirmed to be able to effectively inhibit the growth of tumors.

The effect of targeted magnetic nanopaticles on hepatoma and the expression of bcl-2/bax protein

The effect of targeted magnetic nanoparticles on hepatoma and the underlying mechanism were examined. Nude mice transplanted with a human hepatoma cell line (HepG2 cells) were randomized into 5 groups, including: (1) group A, receiving normal saline, (2) group B, receiving 5-fluorouracil (5-Fu), (3) group C, receiving magnetic nanoparticles containing 5-Fu, (4) group D, consisting of treatment with magnetic nanoparticles containing 5-Fu and inside magnetic field and (5) group E, receiving pure magnetic nanoparticles and inside magnetic field. Morphological features of transplanted tumors in mice in each group were observed under transmission electron microscope (TEM). The expression of bcl-2/bax protein was immunohistochemically detected by SABC method. The results showed that a large number of apoptotic tumor cells were found in group B and group D under TEM. The expression of bcl-2 protein was significantly decreased and the expression of bax protein increased significantly in both group B and D as compared with those in group A, C and E (P<0.01 for all). The decrease in bcl-2 and the increase in bax were more in group D as compared with group B (P<0.01). It is concluded that the targeted magnetic nanoparticles containing 5-Fu can improve the chemotherapeutic effect of 5-Fu by decreasing bcl-2 expression, increasing bax expression and inducing apoptosis of the liver cancer cells.SummaryThe effect of targeted magnetic nanoparticles on hepatoma and the underlying mechanism were examined. Nude mice transplanted with a human hepatoma cell line (HepG2 cells) were randomized into 5 groups, including: (1) group A, receiving normal saline, (2) group B, receiving 5-fluorouracil (5-Fu), (3) group C, receiving magnetic nanoparticles containing 5-Fu, (4) group D, consisting of treatment with magnetic nanoparticles containing 5-Fu and inside magnetic field and (5) group E, receiving pure magnetic nanoparticles and inside magnetic field. Morphological features of transplanted tumors in mice in each group were observed under transmission electron microscope (TEM). The expression of bcl-2/bax protein was immunohistochemically detected by SABC method. The results showed that a large number of apoptotic tumor cells were found in group B and group D under TEM. The expression of bcl-2 protein was significantly decreased and the expression of bax protein increased significantly in both group B and D as compared with those in group A, C and E (P<0.01 for all). The decrease in bcl-2 and the increase in bax were more in group D as compared with group B (P<0.01). It is concluded that the targeted magnetic nanoparticles containing 5-Fu can improve the chemotherapeutic effect of 5-Fu by decreasing bcl-2 expression, increasing bax expression and inducing apoptosis of the liver cancer cells.