Knockdown of long non-coding RNA HOTAIR sensitizes hepatocellular carcinoma cell to cisplatin by suppressing the STAT3/ABCB1 signaling pathway.

Long non-coding RNA HOX transcript antisense RNA (HOTAIR) has been demonstrated to exhibit oncogenic activity in several types of cancer, including hepatocellular carcinoma (HCC). However, the association between HOTAIR and HCC multidrug resistance remains uncertain. The present study aimed to investigate the role of HOTAIR in HCC chemoresistance; it was found that knockdown of HOTAIR expression in HCC Huh7 cells resulted in decreased cell proliferation and increased chemosensitivity to cisplatin. Furthermore, expression levels of ATP binding cassette subfamily B member 1 (ABCB1) mRNA and protein were decreased in Huh7 cells upon HOTAIR-knockdown. In addition, HOTAIR-knockdown reduced the levels of phosphorylated signal transducer and activator of transcription 3 (STAT3), and inhibition of STAT3 phosphorylation reduced HOTAIR-mediated ABCB1 expression. Together, these findings indicated that knockdown of HOTAIR in Huh7 cells decreased STAT3 activity and ABCB1 expression, and increased chemosensitivity to cisplatin. Thus HOTAIR could serve as a novel potential therapeutic target to reverse multidrug resistance in HCC.

Knockdown of Hotair suppresses proliferation and cell cycle progression in hepatocellular carcinoma cell by downregulating CCND1 expression.

The long noncoding RNA, homeobox transcript antisense RNA (Hotair), has been demonstrated to have an important role in regulating various biological processes in various cancers, including hepatocellular carcinoma (HCC). However, the importance of Hotair in HCC proliferation and cell cycle progression remains to be elucidated. In the present study, knockdown of HOTAIR expression by RNA interference inhibited cell proliferation and induced G0/G1 cell cycle arrest in Huh7 hepatocellular carcinoma cells. In addition, the expression levels of CCND1 mRNA and its cyclin D1 protein product were reduced in Huh7 cells following knockdown of HOTAIR. Knockdown of HOTAIR reduced the expression of phosphorylated signal transducer and activator of transcription 3 (STAT3) and HOTAIR knockdown combined with STAT3 inhibition led to an additional decrease in cyclin D1 expression. The present study suggested that Hotair may have a critical role in the proliferation of HCC by regulating cell cycle, STAT3 activity and cyclin D1 expression. Therefore, Hotair may be a novel potential therapeutic target for HCC treatment.

Optimized construction of MUC1-VNTRn DNA vaccine and its anti-pancreatic cancer efficacy.

Considering mucin 1-variable number tandem repeat (MUC1-VNTRn) as a novel target for pancreatic cancer immunotherapy, the present study aimed to screen and identify the pVAX1-MUC1-VNTRn DNA vaccine with the strongest immunogenicity. Following construction of a pVAX1-MUC1-VNTRn plasmid, immature dendritic cells (DCs) were subjected to transfection, and mature DCs were then co-cultured with autologous T-cells. The numbers of cytotoxic T lymphocytes (CTLs) secreting interferon (IFN)-γ were determined using an enzyme-linked immunospot assay, and CytoTox® was also used to examine the MUC1-VNTRn-specific Lethal effect of CTLs on Capan2 cells. Additional in vivo experiments in mice were performed to confirm the antitumor effect of the DNA vaccine candidate. The present study successfully constructed the pVAX1-MUC1-VNTRn plasmid, which expresses the target protein in eukaryotic cells. Additionally, upon uptake of the pVAX1-MUC1-VNTRn plasmid, the immature DCs differentiated into mature DCs. The levels of the DC surface molecules cluster of differentiation (CD) 80, CD86, human leukocyte antigen-antigen D related, interleukin (IL)-12, IL-17 and IFN-γ were significantly higher, while the levels of IL-10 and IL-14 were lower, in mature DCs of the stimulated groups compared with the immature DCs of the non-stimulated groups (all P<0.01). In addition, the MUC1-VNTR6 and MUC1-VNTR9 groups, in which DCs were capable of activating autologous T-cells, showed increased IFN-γ-producing T-cells compared with the other groups (strong MUC1-VNTR1, weak VNTR1, VNTR3, VNTR4 and MUC1-cDNA groups; all P<0.001). In addition, the Lethal effect of CTLs on Capan2 cells in these two groups was stronger compared with the other groups (all P<0.001). Furthermore, the induced protective and therapeutic immune responses in mouse experiments showed that the pVAX1-MUC1-VNTR6DNA vaccine likely possessed the strongest immunogenicity, and its ability to inhibit panc02-MUC1 tumor growth was superior to other DNA vaccines (P<0.01). The present study provides compelling evidence that pVAX1-MUC1-VNTRn has the potential to express the target protein in eukaryotic cells, and thatpVAX1-MUC1-VNTR6 was characterized by the strongest Lethal effect in both in vivo and in vitro experiments.

Hepatitis C virus core protein increases Snail expression and induces epithelial-mesenchymal transition through the signal transducer and activator of transcription 3 pathway in hepatoma cells.

AIM: Aberrant expression of Snail, a mediator of epithelial-mesenchymal transition (EMT), is crucial for cancer invasiveness and metastasis. Although hepatitis C virus (HCV) core protein has been implicated in hepatocarcinogenesis, the relationship between HCV core and Snail expression has not been clarified. METHODS: HepG2 and Huh7 stable cell lines were established by transfection with pcDNA-HCVc. HepG2-HCVc and Huh7-HCVc cells were co-administered with AG490. Cell migration and invasiveness were tested. STAT3 and Snail expression was analyzed by Real-time PCR and Western blot. RESULTS: We found that HCV core is capable of increasing Snail expression and inducing EMT in hepatoma cells. HCV core-induced Snail expression was accompanied by activation of signal transducer and activator of transcription 3 (STAT3), inhibition of STAT3 abrogated HCV core-induced Snail expression and EMT. Furthermore, chromatin immunoprecipitation showed that phosphorylated STAT3 directly binds to the Snail promoter. CONCLUSION: Collectively, these results suggest that HCV core would play a role in hepatocellular carcinoma invasiveness and metastasis by activating the STAT3 pathway, increasing Snail expression and subsequently triggering EMT. These findings would advance the understanding of HCV-mediated invasiveness and metastasis, and might provide a new potential therapeutic target for HCV-related hepatocellular carcinoma.

Hepatitis C virus core protein regulates OCT4 expression and promotes cell cycle progression in hepatocellular carcinoma.

Hepatitis C virus (HCV) core protein plays an important role in the development of hepatocellular carcinoma. octamer-binding protein 4 (OCT4) is critically essential for the pluripotency and self-renewal of embryonic stem cells. Abnormal expression of OCT4 has been detected in several human solid tumors. However, the relationship between HCV core and OCT4 remains uncertain. In the present study, we found that HCV core is capable of upregulating OCT4 expression. The effect of HCV core-induced OCT4 overexpression was abolished by RNAi-mediated scilencing of HCV core. In addition, HCV core-induced OCT4 overexpression resulted in enhanced cell proliferation and cell cycle progression. Inhibition of OCT4 reduced the CCND1 expression and induced G0/G1 cell cycle arrest. Furthermore, OCT4 protein directly binds to CCND1 promoter and transactivates CCND1. These findings suggest that HCV core protein regulates OCT4 expression and promotes cell cycle progression in hepatocellular carcinoma providing new insight into the mechanism of hepatocarcinogenesis by HCV infection.

Linc00675 is a novel marker of short survival and recurrence in patients with pancreatic ductal adenocarcinoma.

AIM: To detect linc00675 expression in pancreatic ductal adenocarcinoma (PDAC), to analyze the relationship between the expression level of linc00675 and the clinical pathological characteristics, to explore the biological functions of linc00675, and to determine whether linc00675 has independent prognostic value in PDAC. METHODS: We studied linc00675 expression among eight histologically confirmed PDAC tissue samples and four chronic pancreatitis tissue samples through microarray screening. RT-qPCR was conducted to further investigate linc00675 expression in PDAC cell lines as well as archived tissues from a large cohort of PDAC patients. The correlations between the level of lnc00675 and clinicopathological characteristics and survival in patients with pancreatic cancer were evaluated using Correlation analysis. Univariate and multivariate analyses were conducted to predict whether lnc00675 expression is an independent prognostic and recurrence factor in patients with pancreatic cancer. After downregulating the expression of linc00675 through siRNA, MTT assay, flow cytometry, transwell assay and Western blot were used to explore the biological function of linc00675 in proliferation, invasion, and cell cycle progression of pancreatic cancer cells. The relative molecular expression levels of epithelial-mesenchymal transition were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. RESULTS: The expression of Linc00675 in PDAC tissue samples was shown to be 672 times that in chronic pancreatitis tissue samples by microarray screening (P = 3.69 × 10(-5)). This finding was confirmed in tumor tissues from 90 patients with PDAC compared with adjacent normal tissue samples by quantitative RT-PCR. We found that linc00675 overexpression positively correlated with lymph node metastasis (P = 0.005), perineural invasion (P = 0.006), and poor survival (P < 0.001). Univariate and multivariate analyses showed that linc00675 expression served as an independent predictor of overall survival (P = 0.009). Additionally, receiver operating characteristic curve analysis showed that high linc00675 might serve as a predictor of tumor progression within 6 mo to a year after surgery. In vitro functional analysis demonstrated that knockdown of linc00675 attenuated pancreatic cancer cell proliferation and invasion as well as induced S phase arrest. Suppression of linc00675 in pancreatic cancer cells resulted can reverse the progress of epithelial-mesenchymal transition. CONCLUSION: Linc00675 may function as an oncogene during PDAC development, and its expression is an independent predictor of unfavorable prognosis in patients with PDAC.

Low RASSF6 expression in pancreatic ductal adenocarcinoma is associated with poor survival.

AIM: To analyze RASSF6 expression in pancreatic ductal adenocarcinoma (PDAC) and to determine whether RASSF6 has an independent prognostic value in PDAC. METHODS: We studied RASSF6 expression in 96 histologically confirmed PDAC samples and 20 chronic pancreatitis specimens using immunohistochemistry and real-time quantitative reverse transcription-PCR. PDAC issues were then classified as RASSF6 strongly positive, weakly positive or negative. RASSF6 mRNA and protein expression in PDAC samples with strong positive staining was further evaluated using real-time PCR and Western blot analysis. Lastly, correlations between RASSF6 staining and patients' clinicopathological variables and outcomes were assessed. RESULTS: RASSF6 was negatively expressed in 51 (53.1%) PDAC samples, weakly positively expressed in 29 (30.2%) and strongly positively expressed in 16 (16.7%), while its expression was much higher in para-tumor tissues and chronic pancreatitis tissues. Positive relationships between RASSF6 expression and T-stage (P = 0.047) and perineural invasion (P = 0.026) were observed. The median survival time of strongly and weakly positive and negative RASSF6 staining groups was 33 mo, 15 mo and 11 mo, respectively. Cox multivariate analysis indicated that RASSF6 was an independent prognostic indicator of overall survival in patients with PDAC. A survival curve analysis revealed that increased RASSF6 expression was correlated with better overall survival (P = 0.009). CONCLUSION: RASSF6 expression is an independent biomarker of an unfavorable prognosis in patients with PDAC.

Click modification of helical amylose by poly(l-lysine) dendrons for non-viral gene delivery.

Although amylose as a naturally-occurring helical polysaccharide has been widely used for biomedical applications, few studies have dealt with its chemical modification for non-viral gene delivery. In this work, the click modification of amylose by poly(l-lysine) dendrons was carried out and then characterized by Fourier transform infrared spectroscopy, wide-angle X-ray diffraction and elemental analyses. Such a modified polysaccharide exhibited excellent ability to condense plasmid pMSCV-GFP-PARK2 into compact and spherical nanoparticles. Moreover, it displayed much lower cytotoxicity when compared to branched polyethylenimine (bPEI, 25kDa), a commercially available gene vector. Similar to bPEI, it had a dose-dependent gene transfection activity in human embryonic kidney 293T cells, as observed by confocal laser scanning microscopy and flow cytometry. At each optimized N/P ratio, the percentage of transfected cells by this modified polysaccharide was found to be comparable to that by bPEI. Western blot and cell apoptosis analyses confirmed its effectiveness for the delivery of plasmid pMSCV-GFP-PARK2 to 293T cells.

The expression levels of transcription factors T-bet, GATA-3, RORγt and FOXP3 in peripheral blood lymphocyte (PBL) of patients with liver cancer and their significance.

OBJECTIVES: To investigate the expression of transcriptional factors (TFs) T-bet, GATA-3, RORγt and FOXP in peripheral blood mononuclear cells (PBMC) of patients with hepatocellular carcinoma (HCC) and to evaluate the correlation between the imbalances of Th1/Th2, Th17/Treg at the expression levels and liver cancer Methods: The peripheral venous blood was drawn from 20 HCC-patients (HCC-group) and 20 health participants (C-group). The expression levels of Th1, Th2 and Th17 and the major Treg-specific TFs T-bet, GATA-3, RORγt and FOXP3 in the PBMC were measured with quantitative real-time PCR(RT-qPCR). RESULTS: The mRNA level of Th1-specific TF T-bet in HCC-group was significantly lower than that of C-group (52.34±34.07 VS 104.01±56.00, P<0.01); the mRNA level of Th2-specifc TF, GATA-3, in HCC group was significantly higher than that in C-group (1.38±1.15 VS 0.58±0.65, P<0.05) and T-bet mRNA/GATA-3 mRNA ratio was significantly lower in HCC-group than in C-group (86.01±116.71 VS 461.88±708.81, P<0.05). The mRNA level of Th17-specific TF RORγt in HCC-group was significantly higher than that of C-group (72.32±32.82 VS 33.07±22.86, P<0.01). Treg-specific TF FOXP3 mRNA level was significant higher in HCC-group than in C-group (3.17±1.59 VS 1.39±1.13, P<0.01) CONCLUSION: T-bet mRNA level was reduced whereas GATA-3 mRNA level was increased and T-bet/GATA-3 ratio was significantly reduced in PBMC, indicating that Th1/Th2 ratio was of imbalance at TF levels in PBMC of HCC, displaying Th2 thrift phenomena. The mRNA levels of RORγt and FOXP3 in PBMC of HCC were significantly increased, indicating the existence of a predominant phenomenon of Th17- and Treg-expressing PBMC in HCC.

Knockdown of NANOG enhances chemosensitivity of liver cancer cells to doxorubicin by reducing MDR1 expression.

Multidrug resistance (MDR) is one of the major reasons for the failure of liver cancer chemotherapy, and its suppression may increase the efficacy of chemotherapy. NANOG plays a key role in the regulation of embryonic stem cell self-renewal and pluripotency. Recent studies reported that NANOG was abnormally expressed in several types of tumors, indicating that NANOG is related to tumor development. However, the correlation between NANOG and liver cancer chemoresistance remains uncertain. In this study, RNA interfere technology was employed to knock down NANOG expression in HepG2 human liver cancer cells. We found that the knockdown of NANOG expression in NANOG siRNA-transfected HepG2 cells resulted in decreased colony formation rate and cell migration compared to control HepG2 cells. In addition, HepG2 cells were treated with doxorubicin to evaluate the chemosensitivity to doxorubicin. We found that the doxorubicin sensitivity of HepG2 cells was increased with downregulation of NANOG expression. The expression of MDR1 at both mRNA and protein levels was decreased in HepG2 cells when NANOG was knocked down. These findings suggest that the knockdown of NANOG in HepG2 human cells resulted in decreased MDR1 expression and increased doxorubicin sensitivity, and NANOG could be used as a novel potential therapeutic target to reverse multidrug resistance of liver cancer.

Hepatitis C virus core protein regulates NANOG expression via the stat3 pathway.

HCV Core plays a role in the development of hepatocellular carcinoma. Aberrant expression of NANOG has been observed in many types of human malignancies. However, relationship between Core and NANOG has not been clarified. In this study, we found that Core is capable of up-regulating NANOG expression. Core-induced NANOG expression was accompanied by enforced expression of phosphorylated stat3 protein and was attenuated by inhibition of stat3 phosphorylation. ChIP showed that phosphorylated stat3 directly binds to the NANOG promoter. Core-induced NANOG expression resulted in enhanced cell growth and cell cycle progression. Knockdown of NANOG blocked the cell cycle at the G0/G1 phases and inhibited the cyclin D1 expression. Our findings provide a new insight into the mechanism of hepatocarcinogenesis by HCV infection.

Transfection of HCVc improves hTERT expression through STAT3 pathway by epigenetic regulation in Huh7 cells.

Previous studies showed that transient transfection of HCVc improved hTERT expression in hepatoma cell lines and it was noteworthy that phosphorylated signal transducer and activator of transcription 3 (pSTAT3) and DNA methyltransferases (DNMTs) were up regulated simultaneously. This study was designed to investigate the role of epigenetic regulation in the process of hTERT up regulation after HCVc transfection. Q-PCR and Western blot were used to analyze the expression of pSTAT3, DNMT1, and hTERT after the transfection of HCVc in hepatoma cell line Huh7. Proliferation and hTERT activity of Huh7 after HCVc transfection were examined by CCK8 and ELISA, respectively. Then, we blocked the JAK/STAT3 pathway or inhibited DNMT1 expression to investigate the regulation of pSTAT3, DNMT1, and hTERT. Methylation status of the promoter of hTERT gene was monitored by MS-PCR. Cell proliferation, hTERT expression level and activity of hTERT were promoted after HCVc transfection. The expression of pSTAT3 and DNMT1 were up-regulated simultaneously. DNMT1 and hTERT were down-regulated after blocking JAK/STAT3 pathway and the expression of hTERT weakened with DNMT1 inhibition. MS-PCR showed HCVc transfection increased the methylation level of hTERT promoter, and this effect was weakened after blocking the JAK/STAT3 pathway or with the treatment with DNMT1 inhibitor. HCVc transfection improved hTERT expression via epigenetic regulation. JAK/STAT3 pathway could be one of the essential factors in regulating DNMT1 expression during this process.

Ophthalmic drug-loaded N,O-carboxymethyl chitosan hydrogels: synthesis, in vitro and in vivo evaluation.

AIM: to investigate the ability of drug-loaded N,O-carboxymethyl chitosan (CMCS) hydrogels to modulate wound healing after glaucoma filtration surgery. METHODS: the drug-loaded CMCS hydrogels were in situ synthesized using genipin as the crosslinker in the presence of 5-fluorouracil (5FU) or bevacizumab. Their structures were characterized by FTIR, ultraviolet-visible (UV-vis) spectroscopy and scanning electron microscopy (SEM). In-vitro drug release experiments and in vivo evaluation in rabbits were performed. RESULTS: the results of FTIR, UV-vis spectroscopy and SEM analyses indicated that 5FU was encapsulated into the CMCS hydrogels that were crosslinked by genipin. The in vitro drug release experiments showed that nearly 100% of 5FU was released from the drug-loaded hydrogels within 8 h, but less than 20% bevacizumab was released after 53 h. The in vivo evaluation in rabbits indicated that the drug-loaded CMCS hydrogels were nontoxic to the cornea and were gradually biodegraded in the eyes. Furthermore, the drug-loaded CMCS hydrogels effectively inhibited conjunctival scarring after glaucoma filtration surgery and controlled postoperative intraocular pressure (IOP). CONCLUSION: the drug-loaded CMCS hydrogels provide a great opportunity to increase the therapeutic efficacy of glaucoma filtration surgery.

Hepatitis C virus core protein induces malignant transformation of biliary epithelial cells by activating nuclear factor-kappaB pathway.

UNLABELLED: In an earlier study, we found that hepatitis C virus core protein, HCV-C, participated in the malignant transformation of HCV-C transfected normal human biliary epithelial (hBE) cells by activating telomerase. Here we further investigated the signaling of the malignant transformation. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR), western blotting and immunoprecipitation were used to analyze the expression of HCV-C, human telomerase reverse transcriptase (hTERT), nuclear factor-kappaB (NF-kappaB) and NF-kappaB inhibitor alpha (IkappaBalpha) genes and the phosphorylation level of IkappaBalpha protein. Electrophoretic mobility shift assays (EMSA) and NF-kappaB-linked luciferase reporter assays were carried out to measure NF-kappaB activity. RESULTS: The expression of HCV-C and hTERT was detected only in HCV-C-transfected hBE (hBE-HCV-C) cells but not in vector-transfected or parental hBE cells. More NF-kappaB protein accumulated in nuclear extracts of hBE-HCV-C cells rather than in those of control cells, though total NF-kappaB protein level showed no difference among these cells. DNA binding activity of NF-kappaB and the NF-kappaB-linked luciferase activity were much higher in HCV-C-transfected hBE cells than those in vector- or non-transfected hBE cells. In addition, the IkappaBalpha phosphorylation level, but not the IkappaBalpha mRNA or protein levels, was increased after HCV-C transfection. CONCLUSIONS: Hepatitis C virus core protein activates NF-kappaB pathway in hBE cells by increasing the phosphorylation of IkappaBalpha. The pathway may be responsible for HCV-C-induced malignant transformation of hBE cells.

[Synthesis of colon-specific prodrug of indomethacin and its inhibitory effect on liver metastasis from colon cancer].

OBJECTIVE: To develop a colon-specific prodrug of Indomethacin microbially triggered, carry out in vitro/in vivo evaluation of drug release, and appraise its inhibitory effect on liver metastasis from colon cancer. METHODS: Indomethacin prodrugs were synthesized and characterized by FTIR and NMR, and dissolution test simulating gastrointestinal tract was employed to screen the colon-specific prodrug. Then, the pharmacokinetic profile of portal vein and peripheral blood in Sprague-Dawley rats was studied. Lastly, the inhibitory effect on liver metastasis from colon cancer in nude mice was observed. RESULTS: The chemical structure characterized by FTIR and NMR demonstrated that six kinds of indomethacin-block-amylose with different drug loading (IDM-AM-1-6) were synthesized, among which IDM-AM-3 was degraded 1.3%, 9.3% and 95.3%, respectively, in simulated gastric fluid for 4 h, small intestine for 6 h, and colon for 36 h. The pharmacokinetic test of IDM-AM-3 showed that absorption was delayed significantly (P < 0.01), peak time [(11.35 + or - 2.45) h], elimination half-life [(16.74 + or - 4.04) h] and mean residence time [(22.27 + or - 0.52) h] were significantly prolonged (P < 0.01), as well as peak serum concentrations [(9.69 + or - 2.40) mg/L] and AUC(0-t) [(236.7 + or - 13.1) mg x L(-1) x h] were decreased markedly (P < 0.01) as compared with those of IDM regarding to portal vein. Additionally, its AUC(0-t) in peripheral blood was remarkably lower than that in Portal vein (P < 0.01). The tumor suppression observation showed that it could remarkably reduce the number of liver metastases in contrast to IDM (P < 0.05). CONCLUSION: Colon-specific IDM-AM-3 possesses advantage of sustained release in portal vein providing some experimental basis for colon-specific delivery system applied to sustained release in the portal vein.

Preparation and antitumor effects of nanovaccines with MAGE-3 peptides in transplanted gastric cancer in mice.

BACKGROUND AND OBJECTIVE: As a prospective vaccine carrier, nanoparticles can protect antigens from degradation and enhance immune response. This study prepared nanovaccines with MAGE-3-derived CD4+-CD8+T cell epitope peptides, and investigated its character and antitumor effects on transplanted gastric cancer in mice. METHODS: We adopted the self-assembly method to prepare peptide/chitosan conjugated with deoxycholic acid (chitosan-deoxycholic acid) nanoparticles. We observed the appearance of the chitosan-deoxycholic acidnanoparticles through a transmission electron microscope (TEM) and analyzed the peptide content and its release pattern by fluorescence spectrophotometry. We observed tumor-suppression efficacy in vivo through animal experiments. RESULTS: We successfully prepared nanoparticles with MAGE-3 peptide antigen, and its encapsulation efficiency and loading level were about 37% and 17.0%, respectively. These nanoparticles presented a delayed release pattern in phosphate buffered saline (PBS) at pH 7.4, and the full release time was about 48 h. In 2 mg/mL lysozyme, the nanoparticles showed a sudden release, and the full release time was about 24 h. ELISPOT and cytotoxic experiments showed that the MAGE-3 peptide loaded nanoparticles could stimulate immune response in vivo and could generate MAGE-3-targeted cytotoxic T lymphocytes (CTLs), and kill MAGE-3-specific tumor cells. Tumor suppression experiments showed that the regression ratio of the peptide-loaded nanoparticles group was 37.81%. CONCLUSIONS: MAGE-3 peptide/chitosan-deoxycholic acidvaccine-loaded nanoparticles can stimulate antitumor immune response in vivo and can regress the growth of mouse forestomach carcinoma cell line MFC.

[Nanoparticle-mediated endostatin gene therapy targeting hepatocellular carcinoma utilizing heat-inducible promoter].

OBJECTIVE: To investigate the inhibitory effect of nanoparticle-mediated endostatin gene therapy on hepatocellular carcinoma xenografts combined with local hyperthermia utilizing heat-inducible promoter. METHODS: Heat-inducible HSP70B promoter and fusion gene of Endo/EGFP were cloned into pcDNA3.1 (+) plasmid, thus obtaining recombinant plasmid of pcDNA3.1 (+)/HSP70-Endo/EGFP using restriction endonucleases BglII/HindIII and EcoRI/SalI. The nanoparticles polylactide-grafted dextran copolymer (DEX-g-PLA) encapsulating the recombinant plasmid DNA were prepared by the method of emulsification and evaporation of organic solvent, and the surface shape of nanoparticles was observed by transmission electron microscope. Human hepatocellular cells of the lines HepG2 and ECV304 were cultured and transfected with the recombinant plasmid utilizing the nanoparticles. Following thermal induction at 37 degrees C, 39 degrees C, 41 degrees C, 43 degrees C, and 45 degrees C for 30 min, the expression of enhanced green fluorescent protein (EGFP) was detected by fluorescence microscope and flow cytometry. The concentration of endostatin protein in the supernatant was tested by ELISA, and the growth inhibition on the HepG2 and ECV304 cells was tested by MTT method. Balb/c nude mice were inoculated with HeG2 cells and then randomly divided into 2 groups to undergo intra-tumor injection of nanoparticles (heated or not heated), Lipofectamine 2000. Mice were used as controls without intra-tumor injection. Four weeks the mice were killed to observe the tumor inhibition rate. RESULTS: The nanoparticles encapsulating recombinant plasmid were of round or elliptical shape 90 approximately 120 nm in diameter. The efficiency of gene transfection mediated by nanoparticles was about 30.65%. The expression of Endo/EGFP gene in the HepG2 cells was up-regulated along with the increase of temperature, peaked at 43 degrees C (with the EGFP expression level 3.3 times as that at 37 degrees C). The concentration of endostatin protein in the supernatant of the 43 degrees C group was (177 +/- 28) microg/L, significantly higher than that of the 37 degrees C group [(41 +/- 10) microg/L]. MTT results indicated that endostatin inhibited the growth of ECV304 cells with a inhibition rate of 96.3% at the time point of 72 h in the 43 degrees C group, however, it did not show influence on HepG2 cells no matter what was the temperature The tumor inhibition rate in the mice of endostatin with thermal induction group was 58.5%, significantly higher than that of the 37 degrees C group (34.9%, P < 0.05). CONCLUSION: Low temperature thermal induction enhances the expression and secretion of endostatin in hepatocellular cells transfected by nanoparticles, and inhibits the growth of hepatocellular carcinoma xenografts.

[Preparation of doxorubicin encapsulated in amphiphilic polysaccharide nanoparticles and anti-hepatocarcinoma effect thereof].

OBJECTIVE: To investigate the sustained release rule of doxorubicin/polylactide-grafted dextran copolymer (DOX/DEX-PLA) nanoparticles and the effect thereof in killing hepatocarcinoma cells. METHODS: DOX/DEX-PLA nanoparticles were prepared by method of emulsification & evaporation of organic solvent. Its morphology was observed by transmission electron microscopy and the encapsulating efficiency of DOX was determined by ultraviolet spectrophotometry. DOX/DEX-PLA was put in a dialysis bag to observe the releasing characteristics of DOX from DOX/DEX-PLA nanoparticles in vitro. Human liver carcinoma cells of the line HepG2 were cultured with DOX/DEX-PLA of different concentrations or the original drug of DOX as control group for 24, 36, or 48 h. MTT method was used to observe the cancer inhibition rate. BALB/c nude mice underwent subcutaneous injection of HepG2 cells at the right scapula and then randomly divided into 4 groups to undergo intravenous injection of DOX/DEX-PLA (excremental group), original drug of DOX (naked drug group), DEX-PLA (nanovector group), or normal saline (blank control group) once every 5 days for 3 times. Twenty-one days later the mice were killed with the tumors taken out to measure the weight to analyze the inhibitory effect against hepatocarcinoma cells. RESULTS: The DOX/DEX-PLA nanoparticles were of round or elliptical shape with the diameter of about 83 nm, and the DOX entrapment efficiency was about 67.1%. The releasing test in vitro manifested a sustained release of over 50% of DOX encapsulated in DOX/DEX-PLA nanoparticles for about 7 days. Both the DOX/DEX-PLA nanoparticles and naked drug DOX inhibited the growth of HepG2 cells with a similar inhibitory rate (51.3% vs 50.7%, P > 0.05), meanwhile the DEX-PLA nanovector failed to inhibit the HepG2 cells. In-vivo experiment showed an inhibitory rate of DOX/DEX-PLA nanoparticles on hepatocellular carcinoma xenografts of 68.56%, significantly higher than that of the naked drug DOX (48.17%). CONCLUSION: DOX/DEX-PLA nanoparticles can effectively inhibit the growth of hepatocarcinoma cells.

[Therapeutic clinical effect of radiofrequency ablation for small hepatocellular carcinoma in cirrhotic patients: a meta-analysis].

OBJECTIVE: To evaluate the value of radiofrequency ablation in the treatment of small hepatocellular carcinoma (HCC). METHODS: MEDLINE (1966 - 2008), EMBASE (1966 - 2008), CBMdisc (1978 - 2008) were searched. The Cochrane Library, Evidence Base Medicine Reviews (Ovid Edition), Cancerlit (1993 - 2008) and so on, date of last search: 30 January 2008. There were no restrictions in language. Randomized controlled trials (RCTs) and non-RCTs were both included in this study, and the quality of each included study was assessed. Meta-analysis was performed by RevMan 4.2 software. RESULTS: Four prospective controlled studies and two retrospective studies met the inclusion criteria. The results of meta-analysis showed that 1-, 3-, 4-year survival rates and 1-year tumor-free survival rate had not statistically significant difference in RFA group compared with surgical resection group (P > 0.05), but surgical resection was more effective to improve 3-year tumor-free survival rate than RFA (P < 0.05). CONCLUSIONS: The effect of RFA therapy on small HCC is similar to resection, RFA could be considered as the first-line treatment of choice for surgical candidates with small HCC in cirrhotic patients.

Preoperative evaluation with T-staging system for hilar cholangiocarcinoma.

AIM: To investigate the clinical value of T-staging system in the preoperative assessment of hilar cholangiocarcinoma. METHODS: From March 1993 to January 2006, 85 patients who had cholangiocarcinoma diagnosed by operative tissue-biopsy were placed into one of three stages based on the new T-staging system, and it was evaluated the resectability and survival correlated with T-staging. RESULTS: The likelihood of resection and achieving tumor-free margin decreased progressively with increasing T stage (P < 0.05). The cumulative 1-year survival rates of T1, T2 and T3 patients were 71.8%, 50.8% and 12.9% respectively, and the cumulative 3-year survival rate was 34.4%, 18.2% and 0% respectively; the survival of different stage patients differed markedly (P < 0.001). Median survival in the hepatic resection group was greater than in the group that did not undergo hepatic resection (28 mo vs 18 mo; P < 0.05). The overall accuracy for combined MRCP and color Doppler Ultrasonagraphy detecting disease was higher than that of combined using CT and color Doppler Ultrasonagraphy (91.4% vs 68%; P < 0.05 ). And it was also higher in detecting port vein involvement (90% vs 54.5%; P < 0.05). CONCLUSION: The proposed staging system for hilar cholangiocarcinoma can accurately predict resectability, the likelihood of metastatic disease, and survival. A concomitant partial hepatectomy would help to attain curative resection and the possibility of long-term survival. MRCP/MRA coupled with color Doppler Ultrasonagraphy was necessary for preoperative evaluation of hilar cholangiocarcinoma.