TP53 R249S mutation detected in circulating tumour DNA is associated with Prognosis of hepatocellular carcinoma patients with or without hepatectomy.

BACKGROUND AND AIMS: Somatic mutation R249S in TP53 is highly common in hepatocellular carcinoma (HCC). We aim to investigate the effects of R249S in ctDNA on the prognosis of HCC. METHODS: We analysed three cohorts including 895 HCC patients. TP53 mutation spectrum was examined by direct sequencing of genomic DNA from tissue specimens in HCC patients with hepatectomy (Cohort 1, N = 260). R249S and other recurrent missense mutations were assessed for their biological functions and associations with overall survival (OS) and progression-free survival (PFS) of HCC patients in Cohort 1. R249S within circulating tumour DNA (ctDNA) was detected through droplet digital polymerase chain reaction (ddPCR) and its association with OS and PRS was analysed in HCC patients with (Cohort 2, N = 275) or without (Cohort 3, N = 360) hepatectomy. RESULTS: In Cohort 1, R249S occupied 60.28% of all TP53 mutations. Overexpression of R249S induced more serious malignant phenotypes than those of the other three identified TP53 recurrent missense mutations. Additionally, R249S, but not other missense mutations, was significantly associated with worse OS (P = .006) and PFS (P = .01) of HCC patients. Consistent with the results in Cohort 1, HCC patients in Cohorts 2 and 3 with R249S had worse OS (P = 8.291 × 10-7 and 2.608 × 10-7 in Cohorts 2 and 3, respectively) and PFS (P = 5.115 × 10-7 and 5.900 × 10-13 in Cohorts 2 and 3, respectively) compared to those without this mutation. CONCLUSIONS: TP53 R249S mutation in ctDNA may serve as a promising prognosis biomarker for HCC patients with or without hepatectomy.

[Factors in first-time adrenocorticotropic hormone therapy and their influence on spasm control time in infantile spasms: a Cox proportional-hazards regression model analysis].

OBJECTIVE: To investigate the factors in first-time adrenocorticotropic hormone (ACTH) therapy and their influence on spasm control time in infants with infantile spasms. METHODS: A total of 72 infants with infantile spasms who were admitted from January 2008 to October 2013 were enrolled. Their clinical data were collected, and the exposure factors for infantile spasms were selected. A Cox proportional-hazards regression model analysis was performed for these factors to analyze their influence on spasm control time. RESULTS: Clarification of the etiology (known or unexplained etiology), frequency of spasms before treatment, and presence or absence of combination therapy (ACTH used alone or in combination with magnesium sulfate) had a significant influence on spasm control time in infants with infantile spasms. The infants with a known etiology had a significantly shorter spasm control time than those with unexplained etiology, and the infants with a low frequency of spasms before treatment and receiving ACTH combined with magnesium sulfate early had a significantly longer spasm control time than their counterparts (P<0.05). CONCLUSIONS: For infants with infantile spasms at initial diagnosis, etiology should be clarified, which may helpful for evaluating prognosis. A combination of ACTH and magnesium sulfate should be given as soon as possible, which may improve their prognosis.

Genetic variants in five novel loci including CFB and CD40 predispose to chronic hepatitis B.

UNLABELLED: Hepatitis B virus affects more than 2 billion people worldwide, 350 million of which have developed chronic hepatitis B (CHB). The genetic factors that confer CHB risk are still largely unknown. We sought to identify genetic variants for CHB susceptibility in the Chinese population. We undertook a genome-wide association study (GWAS) in 2,514 CHB cases and 1,130 normal controls from eastern China. We replicated 33 of the most promising signals and eight previously reported CHB risk loci through a two-stage validation totaling 6,600 CHB cases and 8,127 controls in four independent populations, of which two populations were recruited from eastern China, one from northern China and one from southern China. The joint analyses of 9,114 CHB cases and 9,257 controls revealed significant association of CHB risk with five novel loci. Four loci are located in the human leukocyte antigen (HLA) region at 6p21.3, including two nonsynonymous variants (rs12614 [R32W] in complement factor B [CFB], Pmeta =1.28 × 10(-34) ; and rs422951 [T320A] in NOTCH4, Pmeta = 5.33 × 10(-16) ); one synonymous variant (rs378352 in HLA-DOA corresponding to HLA-DOA*010101, Pmeta = 1.04 × 10(-23) ); and one noncoding variant (rs2853953 near HLA-C, Pmeta = 5.06 × 10(-20) ). Another locus is located at 20q13.1 (rs1883832 in the Kozak sequence of CD40, Pmeta = 2.95 × 10(-15) ). Additionally, we validated seven of eight previously reported CHB susceptibility loci (rs3130542 at HLA-C, rs1419881 at TCF19, rs652888 at EHMT2, rs2856718 at HLA-DQB1, rs7453920 at HLA-DQB2, rs3077 at HLA-DPA1, and rs9277535 at HLA-DPA2, which are all located in the HLA region, 9.84 × 10(-71) ≤ Pmeta ≤ 9.92 × 10(-7) ). CONCLUSION: Our GWAS identified five novel susceptibility loci for CHB. These findings improve the understanding of CHB etiology and may provide new targets for prevention and treatment of this disease.

Aberrant estrogen receptor alpha expression correlates with hepatocellular carcinoma metastasis and its mechanisms.

BACKGROUND/AIMS: Metastasis one of the obstacles before poor prognosis of hepatocellular carcinoma (HCC) is improved. Estrogen receptor alpha (ERalpha) plays an important role in the development and progression of HCC. However, the molecular mechanism of ERalpha in mediating HCC metastasis is still unclear. The aim of the present study was to detect aberrant ERalpha expression in HCC and elucidate its possible mechanisms in HCC metastasis. METHODOLOGY: We detected expression of ERalpha, phospho-estrogen receptor alpha (p-ERalpha), nuclear factor kappa B (NF-kappaB) p65 and Matrix metalloproteinase-9 (MMP-9) between HCC tissues with portal vein tumor thrombus (PVTT) and those without PVTT by immunohistochemical method. Moreover, the expression of above parameters was also determined in HCC cells of different metastatic potential by using immunocytochemical and reverse transcriptase-polymerase chain reaction (RT-PCR) methods. RESULTS: The expression of ERalpha and p-ERalpha was lower in HCC with PVTT than those without PVTT. Meanwhile, the expression pattern of above parameters was also similar in HCC cells of different metastatic potential, whereas, the expression of NF-kappaB p65 and MMP-9 was higher in HCC with PVTT than those without PVTT. The expression of NF-kappaB p65 and MMP-9 in HCC cells was also analogous to the tissues. CONCLUSIONS: These results demonstrated that expression of ERalpha, p-ERalpha, NF-kappaB p65 and MMP-9 correlated with invasion and metastasis in HCC. The mechanism of HCC metastasis may mediate through cross-talk between the NF-KB and ER signaling pathways. Meanwhile, ERa regulated MMP-9 through NF-kappaB indirectly.

Overexpression of HOXA13 as a potential marker for diagnosis and poor prognosis of hepatocellular carcinoma.

HOXA13 is a member of homeobox genes that encode transcription factors regulating embryonic development and cell fate. Abnormal HOXA13 expression was reported in hepatocellular carcinoma (HCC), but its correlation with tumor angiogenesis and prognosis still remain unclear. This study was aimed to uncover the expression, diagnostic and prognostic significance of HOXA13 in HCC. Immunohistochemistry was performed to detect HOXA13 expression in HCC and corresponding paracarcinomatous tissues from 90 patients. Enzyme-linked immunosorbent assay was used to detect serum HOXA13 in 90 HCC patients and 20 healthy volunteers. Receiver operating characteristics was analyzed to calculate diagnostic accuracy of serum HOXA13, alpha-fetoprotein (AFP) and their combination. Immunoreactivity of HOXA13 was detected in 72.2% of HCC, and 12.2% of adjacent non-cancerous samples. HOXA13 expression was significantly associated with tumor size, microvascular invasion, pathological grade, tumor capsula status, AFP level, tumor-node-metastasis stage and positively correlated with VEGF (p < 0.001) and microvessel density (p < 0.001). The combination of serum HOXA13 and AFP had a markedly higher area under the curve than HOXA13 alone. HOXA13 expression was associated with unfavorable overall survival (OS) (p < 0.001) and disease-free survival (DFS) (p < 0.001). Multivariate analysis indicated that patients with HOXA13-expressing tumors had a significantly shorter OS (p = 0.030) and DFS (p = 0.005) than those with HOXA13-negative tumors. Thus, HOXA13 expression possibly plays an important role in tumor angiogenesis, progression and prognosis of HCC. Moreover, we demonstrate that serum HOXA13 may serve as a biomarker for early HCC diagnosing and predicting outcome.

Prognostic significance of osteopontin in hepatocellular carcinoma: a meta-analysis.

Osteopontin (OPN) has been implicated in tumor development and progression for several years. However, the prognostic value of OPN overexpression in patients with hepatocellular carcinoma (HCC) remains controversial. We performed a meta-analysis to assess the relationship between OPN overexpression and clinical outcome of HCC. A meta-analysis of seven studies (1,158 patients) was carried out to evaluate the association between OPN and overall survival (OS) and disease-free survival (DFS) in HCC patients. The correlation between OPN and tumor vascular invasion or other invasion-related parameters was also assessed. Data were synthesized with random effect model of DerSimonian and Laird, hazard ratio (HR) or odds ratio (OR) with its 95% confidence interval (CI) was used as the effect size estimate. Our analysis results indicated that high OPN expression predicted poor OS (HR: 1.37, 95% CI: 1.21-1.55) and DFS (HR: 1.62, 95% CI: 1.24-2.11) of HCC. OPN overexpression tended to be associated with the presence of tumor vascular invasion (OR: 1.93, 95% CI: 0.97-3.84) and advanced tumor grade (OR: 1.74, 95% CI: 0.95-3.18). By this study, we conclude that OPN overexpression indicates a poor prognosis for patients with HCC, it may also have predictive potential for HCC invasion and metastasis.

Activation of STAT3 signal pathway correlates with twist and E-cadherin expression in hepatocellular carcinoma and their clinical significance.

BACKGROUND: To examine the expression of signal transducer and activator of transcription 3 (STAT3) and its activated form (p-STAT3), Twist, and E-cadherin in hepatocellular carcinoma (HCC), and explore their correlations with HCC progression and prognosis. MATERIALS AND METHODS: The expression profiles of STAT3, p-STAT3, Twist, and E-cadherin were assessed on 100 clinical HCC samples and 10 normal liver tissues by using an immunohistochemical staining method, and their correlations with clinicopathologic parameters and survival of HCC patients were statistically analyzed. RESULTS: The results demonstrated that the positive rate of STAT3, p-STAT3, and Twist in HCC was significantly higher than that in normal liver tissues; furthermore, 52% of HCC lesions showed reduced E-cadherin expression. Correlation analysis indicated that p-STAT3 was positively correlated with Twist expression, whereas Twist was negatively correlated with E-cadherin expression; p-STAT3, Twist, or E-cadherin expression was significantly associated with HCC invasion and metastasis. Survival analysis showed that HCC patients with p-STAT3, Twist positive expression, or reduced E-cadherin expression had a significantly shorter survival duration than those with p-STAT3, Twist negative expression, or those with normal E-cadherin expression. Multivariate analysis identified p-STAT3, Twist, or E-cadherin expression as an independent prognostic factor for overall survival of HCC patients after surgery. CONCLUSIONS: By this study, we suggest that activated STAT3 signal may associate with Twist and E-cadherin expression and mediate HCC invasiveness and metastasis; abnormal p-STAT3/Twist/E-cadherin signal axis may predict poor prognosis of HCC patients.

Protective effects of physiological doses of estrogen during hepatocarcinogenesis induced by diethylnitrosamine and N-nitrosomorpholine.

BACKGROUND/AIMS: Concern that much controversy exists with respect to the role of estrogen in hepatocarcinogenesis prompted us to examine the effect of estrogen, at physiological concentrations, on our established HCC rat model induced by diethylnitrosamine and N-nitrosomorpholine. METHODOLOGY: Female Sprague-Dawley rats were randomly divided into four groups (Group 1: Control, Group 2: Sham-operated, Group 3: Ovariectomy, Group 4: ovariectomy+estrogen) with treatment of a single i.p. injection of diethylnitrosamine (100mg/ kg body weight) followed by N-nitrosomorpholine (100ppm) in drinking water for 20 weeks for the established rat HCC model. Physiological estrogen was administered by 17α-Ethynylestradiol at a dose of 30µg/ kg body weight while rats in the sham-operated group were treated with saline after initiation of liver carcinogenesis. RESULTS: Treatment of ovariectomized animals with 17α-Ethynylestradiol (30µg/kg body weight/ day) resulted in a significant decrease in the initiation, development and metastasis of HCC and an increase in the survival time of animals dead before the termination of experiment as compared with rats treated with ovariectomy only (p<0.05); whereas this difference disappeared when compared with the other three groups. CONCLUSIONS: These findings show for the first time that estrogen, at physiological concentrations may reveal a protective role in hepatocarcinogenesis.

Development of transferrin functionalized poly(ethylene glycol)/poly(lactic acid) amphiphilic block copolymeric micelles as a potential delivery system targeting brain glioma.

The aim of present study is to conceive a biodegradable poly(ethylene glycol)-polylactide (PEG-PLA) copolymer nanoparticle which can be surface biofunctionalized with ligands via biotin-avidin interactions and used as a potential drug delivery carrier targeting to brain glioma in vivo. For this aim, a new method was employed to synthesize biotinylated PEG-PLA copolymers, i.e., esterification of PEG with biotinyl chloride followed by copolymerization of hetero-biotinylated PEG with lactide. PEG-PLA nanoparticles bearing biotin groups on surface were prepared by nanoprecipitation technique and the functional protein transferrin (Tf) were coupled to the nanoparticles by taking advantage of the strong biotin-avidin complex formation. The flow cytometer measurement demonstrated the targeting ability of the nanoparticles to tumor cells in vitro, and the fluorescence microscopy observation of brain sections from C6 glioma tumor-bearing rat model gave the intuitive proof that Tf functionalized PEG-PLA nanoparticles could penetrate into tumor in vivo.

[Expression of estrogen receptor α in hepatitis B-related hepatocellular carcinoma and its clinical significance].

OBJECTIVE: To investigate the expression and its clinical significance of estrogen receptor (ERα) and phosphorylated estrogen receptor (p-ERα) in patients with hepatocellular carcinoma. The associations between ERα, p-ERα and IL-6 were also analyzed. METHODS: Immunohistochemistry was used to detect the expression of ERα, p-ERα and IL-6 in tumor tissues from 77 cases with hepatocellular carcinoma. The relations between ERα and the clinical pathological parameters and prognosis were also analyzed. RESULTS: The positive rates of ERα, p-ERα and IL-6 in hepatocellular carcinoma were 39.0% (30/77), 45.4% (35/77) and 72.7% (56/77), respectively. The expression of ERα and p-ERα were negatively correlated with the expression of IL-6 (r=-0.468, P<0.01; r=-0.370, P<0.01, respectively). The positive rate of ERα in patients with tumor size≤5 cm, serum level of alpha-fetoprotein<400 µg/L, with complete encapsulation and non-microvascular invasion was significantly higher than those with tumor size>5 cm, serum level of alpha-fetoprotein≥400 µg/L, non-complete encapsulation and with microvascular invasion (all P<0.05). The overall survival rates of ERα-positive and ERα-negative patients were 66.7% and 23.4% (P<0.05). And the disease-free survival rates of ERα-positive and ERα-negative patients were 83.3% and 57.4% (P<0.05). CONCLUSIONS: The tumor biological features of ERα-positive patients are better than that of ERα-negative patients. The role of ERα in hepatocellular carcinoma may be related to IL-6 level.

Functionalized Reduced Graphene Oxide Loaded Aligned Carbon Nanotube Layer Used as Counter Electrode for Dye-Sensitized Solar Cells.

A novel bilayer counter electrodes for Dye-sensitized Solar Cells (DSSCs) made of reduced graphene oxide (RGO) and aligned carbon nanotube (ACNT) was developed. The underlayer ACNT severs as a transition layer for RGO. The overlayer of RGO plays the role of catalytic layer. It was demonstrated that the property of graphene counter electrode was adversely affected by aggregation, by adding surfactant, the aggregation of graphene can be inhabited effectively. Moreover, the interface between the RGO and the ACNT can be optimized by surfactant functionalization of RGO. After screening, a cationic surfactant cetylpyridinium chloride (CPC) functionalized RGO, code as CPC-RGO, exhibits the best performance. Compare to the ACNT based counter electrode and other surfactant functionalized RGO/ACNT based bilayer counter electrodes, the CPC-RGO/ACNT reduced interface resistance and improved the double chemical capacitance efficiently, thus uplifting the short circuit current density and fill factor from 7.35 to 8.8 mA cm-2, and 59.87 to 62.79, respectively. Eventually, the CPC-RGO/ACNT based DSSC giving a power conversion efficiency of 3.9%, which is 1.24-fold than that of ANCT based DSSC, because of the best splay degree of CPC/RGO.

Adiponectin deficiency impairs liver regeneration through attenuating STAT3 phosphorylation in mice.

Liver regeneration is a very complex and well-orchestrated process associated with signaling cascades involving cytokines, growth factors, and metabolic pathways. Adiponectin is an adipocytokine secreted by mature adipocytes, and its receptors are widely distributed in many tissues, including the liver. Adiponectin has direct actions in the liver with prominent roles to improve hepatic insulin sensitivity, increase fatty acid oxidation, and decrease inflammation. To test the hypothesis that adiponectin is required for normal progress of liver regeneration, 2/3 partial hepatectomy (PH) was performed on wild-type and adiponectin-null mice. Compared to wild-type mice, adiponectin-null mice displayed decreased liver mass regrowth, impeded hepatocyte proliferation, and increased hepatic lipid accumulation. Gene expression analysis revealed that adiponectin regulated the gene transcription related to lipid metabolism. Furthermore, the suppressed hepatocyte proliferation was accompanied with reduced signal transducer and activator of transcription protein 3 (STAT3) activity and enhanced suppressor of cytokine signaling 3 (Socs3) transcription. In conclusion, adiponectin-null mice exhibit impaired liver regeneration and increased hepatic steatosis. Increased expression of Socs3 and subsequently reduced activation of STAT3 in adiponectin-null mice may contribute to the alteration of the liver regeneration capability and hepatic lipid metabolism after PH.

A somatostatin analogue, octreotide, inhibits the occurrence of second primary tumors and lung metastasis after resection of hepatocellular carcinoma in mice.

Occurrence of second primary tumors and metastasis remains the major obstacles to prolonged survival of patients with primary hepatocellular carcinoma (HCC). A somatostatin analogue, octreotide, has been previously reported to inhibit the growth of human HCC xenografts in nude mice through its anti-angiogenic activity. It is therefore important to investigate whether octreotide could prevent second primary hepatomas or distant metastasis following resection of primary HCC. In this study, nude mice, bearing the human HCC xenografts with highly metastatic potential (LCI-D20) in the left liver lobe, underwent tumor resection, and received intraperitoneal administration of octreotide or saline as a control for 35 consecutive days. Compared with the control group, octreotide at the doses of 100 and 200 microg/kg/day significantly inhibited the growth (P < 0.001 and P < 0.001, respectively) and incidence of second primary tumors (P = 0.016 and P = 0.001, respectively), decreased lung metastasis (P < 0.001 and P < 0.001, respectively), and prolonged the life span (P = 0.029 and P = 0.006, respectively). Moreover, intratumoral angiogenesis quantified by microvessel density as well as serum and tissue vascular endothelial growth factor (VEGF) levels were considerably decreased in octreotide-treated animals compared to the control animals. These findings suggest that octreotide may prevent the occurrence of second primary hepatomas and lung metastasis after resection of primary HCC, which may be partially attributed to down-regulation of VEGF and subsequent reduction in tumor angiogenesis. Octreotide administration may be useful as an adjuvant therapy to improve survival of patients with HCC.

Regulatory role of hippocampal PI3K and mTOR signaling pathway in NMDA-induced infant spasm rats.

Objectives: To explore the role of mTOR signaling pathway in modulating epileptogenesis in an N-methyl-D-aspartic acid (NMDA)-induced infant spasm (IS) rat model. Methods: After inducing IS successfully, the phosphorylation status of PI3K, Akt, mTOR and S6K of brain and hippocampus tissues was assessed using western blot and immunochemistry analysis, respectively. The possible mechanism of mTOR signaling pathway was evaluated by the, inhibitors for mTOR and PI3K, rapamycin and wortmannin, respectively. The inhibitors were injected into the intraperitoneal space of the rats to examine the effects of PI3K and mTOR in IS rat model. Results: The phosphorylated levels of mTOR and PI3K in hippocampus increased significantly (P < 0.05) 7 days after IS induction in rats. After administration of wortmannin, the phosphorylated levels of PI3K and mTOR decreased. However, only the phosphorylated level of mTOR decreased obviously after rapamycin administration. No obvious neurogenesis was found after IS induction. Discussion: Results of the present study suggest that hippocampal PI3K may be another potential target for IS treatment.

[Small interfering RNA inhibits the expression of connexin43 in the human corpus cavernosum penis smooth muscle cells].

OBJECTIVE: To inhibit the expression of connexin43 (Cx43) in the human corpus cavernosum penis smooth muscle cells by small interfering RNA (siRNA) and detect the gap junction intercellular communication (GJIC), and to investigate the application of siRNA technology in the gap junction of corpus cavernosum penis smooth muscle cells and its role in the penile erection process. METHODS: With the help of the software of Ambion Corporation, the specific recombinant plasmids with siRNA targeting human Cx43 gene were constructed. The recombinant plasmids having been stably transferred into human corpus cavernosum penis smooth muscle cells for 48 hours, semi-quantitive reverse transcription polymerase chain reaction (RT-PCR) and Western blotting techniques were used to examine the inhibitory effects of siRNA on the expressions of the Cx43 gene and protein, in comparison with the siRNA negative control and the blank control group, respectively. The GJIC was detected by scrape-loading and fluorescence dye transfer experiments through the fluorescence microscope. RESULTS: The results of enzyme digestion analysis and DNA sequencing showed that the recombinant plasmid pSilencer 1.0-U6-siRNA-Cx43 was successfully constructed. The relative levels of Cx43 mRNA and protein expression in the smooth muscle cells were (0.45 +/- 0.08)% and (0.56 +/- 0.06)% after successful transfer of the recombinant plasmid. However, the expression levels of mRNA and protein were (0.72 +/- 0.04)% and (0.80 +/- 0.08)% in the negative siRNA transfer group, and (0.74 +/- 0.09)% and (0.77 +/- 0.11)% in the blank control, respectively, with a significant difference (P < 0.05). The GJIC also decreased significantly. CONCLUSION: siRNA can significantly inhibit the expression of Cx43 and block the GJIC in the human corpus cavernosum penis smooth muscle cells. siRNA technology plays an important role in penile erection and flaccidity.

Variants on 8q24 and prostate cancer risk in Chinese population: a meta-analysis.

Previous studies have identified 8q24 as an important region to prostate cancer (PCa) susceptibility. The aim of this study was to investigate the role of six genetic variants on 8q24 (rs1447295, A; rs6983267, G; rs6983561, C; rs7837688, T; rs10090154, T and rs16901979, A) on PCa risk in Chinese population. Online electronic databases were searched to retrieve related articles concerning the association between 8q24 variants and PCa risk in men of Chinese population published between 2000 and 2014. Odds ratio (ORs) with its 95% correspondence interval (CI) were employed to assess the strength of association. Total eleven case-control studies were screened out, including 2624 PCa patients and 2438 healthy controls. Our results showed that three risk alleles of rs1447295 A (OR=1.35, 95% CI=1.19-1.53, P<0.00001), rs6983561 C (C vs. A: OR=1.41, 95% CI=1.21-1.63, P<0.00001) and rs10090154 T (T vs. C: OR=1.48, 95% CI=1.22-1.80, P<0.00001) on8q24 were significantly associated with PCa risk in Chinese population. Furthermore, genotypes of rs1447295, AA+AC; rs6983561, CC+AC and CC; rs10090154, TT+TC; and rs16901979, AA were associated with PCa as well (P<0.01). No association was found between rs6983267, rs7837688 and PCa risk. In conclusions, variants including rs1447295, rs6983561, rs10090154 and rs16901979 on 8q24 might be associated with PCa risk in Chinese population, indicating these four variations may contribute risk to this disease. This meta-analysis was the first study to assess the role of 8q24 variants on PCa risk in Chinese population.

P15 gene methylation in hepatocellular carcinomas: a systematic review and meta-analysis.

OBJECTIVE: This study was performed to investigate the correlation between P15 methylation and hepatocellular carcinoma (HCC) and hepatocirrhosis using a meta-analysis of available case control studies. METHODS: Previous studies have primarily evaluated the incidence of P15 methylation in HCC and corresponding control groups, and compared the incidence of P15 methylation in liver cirrhosis and control groups. Data regarding publication information, study characteristics, and incidence of P15 methylation in both groups were collected from these studies and summarized. RESULTS: Ten studies that assessed P15 gene methylation in 824 HCC tumour tissues and five studies analyzing P15 methylation in 155 liver cirrhosis tissues met our inclusion criteria. Our meta-analysis revealed that the rate of P15 methylation was significantly higher in HCCs than in adjacent non-tumour tissues (OR 9.04, 95% CI 5.80-14.09, P < 0.00001). Moreover, P15 methylation was significantly higher in liver cirrhosis tissues than in control tissues (OR 7.82, 95% CI 3.58-17.07, P < 0.00001). CONCLUSIONS: we found that P15 methylation was associated with an increased risk of HCC and liver cirrhosis. P15 hypermethylation induced the inactivation of the P15 gene, which played an important role in hepatocarcinogenesis.

[Development of salivary gland tumors in pleomorphic adenoma gene 1 transgenic mice].

OBJECTIVE: Activation and overexpression of pleomorphic adenoma (PLAG1) gene due to t(3;8)(p21;q12) translocation are associated with the development of human pleomorphic adenomas of the salivary glands. This study was conducted to generate ubiquitously-expressed or tissue-specific expressed PLAG1 transgenic mice and to elucidate the role of PLAG1 gene in tumorigenesis in vivo. METHODS: Human PLAG1 cDNA was cloned from salivary gland tumor or placenta tissues by RT-PCR. Ubiquitous expression vector pCMV-EGFP/PLAG1 driven by CMV promoter and tissue-specific expression vector pMMTV-PLAG1 driven by MMTV LTR were constructed. NIH3T3 cells transiently transfected with pCMV-EGFP/PLAG1 showed high expression of PLAG1 in nucleus. Transgenes were microinjected into pronucleus of zygotes to generate transgenic mice. RESULTS: It was found that the human PLAG1 cDNA cloned from several salivary gland tumor and normal placenta tissues consistently showed a variation of a single nucleotide at the same position when compared with the human PLAG1 cDNA sequence in Genbank (Accession No. U65002), which led to T458P at protein level. It might be a single nucleotide polymorphism (SNP)locus. Fused EGFP/PLAG1 protein was found to be localized in the nucleus of NIH3T3 cells transiently transfected with pCMV-EGFP/ PLAG1. Several pCMV-EGFP/PLAG1 and pMMTV-PLAG1 transgenic mouse lines were obtained respectively. As might be expected, pMMTV-PLAG1 transgenic mice spontaneously developed salivary gland tumors in three independent lines, among which, line 42 showed tumorigenic phenotype in 100% of transgenic mice within three months after birth. CONCLUSION: Overexpression of PLAG1 gene plays a crucial role in tumorigenesis of salivary gland tumors.

siRNA-mediated knockdown of hTDE2 retards cell cycle progression through transcriptional activation of p21.

Carcinogenesis is a very complex process involving a series of changes of tumor-related genes. Therefore, genes differentially expressed in tumors have received significant attention. Among them is the tumor differentially expressed (TDE) protein family, which shows no homologue to any other protein families and is unique to eukaryotes. The members of the TDE (also known as Serinc) family are highly conserved, showing approximately 30-80% homologue of their amino acid sequences. Previous reports have shown that both human and mice TDE/Serinc proteins are always upregulated in carcinomatous tissues. However, their precise physiological roles remain unclear. The human TDE2/Serinc1 gene was cloned by our laboratory during the screening for differentially expressed genes in hepatocarcinoma. In the present study, we knocked down the expression of TDE2 with specific siRNA fragments in two human hepatocarcinoma cell lines, and this caused cell cycle arrest at G2. Cell cycle progression is monitored and regulated by several factors. p21, the cdk inhibitor, is a key player and could be transcriptionally activated by many factors including sterol regulatory element-binding proteins (SREBPs). Previous research demonstrated that rat TDE2 could facilitate the cellular sphingolipids biosynthesis in both yeast and mammalian cells. Therefore, we further analyzed the effect of TDE2 knockdown on p21 and SREBP, and found that endogenous p21 expression was upregulated, as was that of SREBPs (-1a and 2). In conclusion, our preliminary results indicated that TDE2 may have an effect on tumor cell growth by influencing the expression of SREBP and p21.

X-linked inhibitor of apoptosis-associated factor l (XAFl) enhances the sensitivity of colorectal cancer cells to cisplatin.

The purpose of present study was to investigate the roles of X-linked inhibitor of apoptosis-associated factor l (XAFl) in regulation apoptosis of colorectal cancer (CRC) cells after treatment with cisplatin (DDP). A total of ten paired cancerous and non-cancerous tissues were collected from patients with CRC after surgery. The levels of XAFl protein were detected by Western blot. Primary CRC cells were separated from cancer tissues, and its viability or apoptosis after treatment with DDP was determined with MTT or Annexin V/PI assays, respectively. Furthermore, we either up-regulated transfecting a XAF1 overexpression vector or down-regulated XAF1 by siRNA interference. And then, the XAF1 levels and its sensitivity to cisplatin were assessed. XAFl had a lower expression in the cancerous tissues from samples T1, T2 and T3 than their paired non-cancerous tissues N1, N2 and N3. However, the expression of XAF1 was not detected in samples T4 and N1. XAF1 levels in cancer tissues significantly decreased in comparison with normal tissues. Cell abilities of primary cells were significantly decreased in a dose-dependent manner, after treatment with a series concentrations of cisplatin (2, 5, 10 µg/mL) for 48 h. Although, after down-expression of XAFl by siRNA, cisplatin caused a significant decreases in apoptosis rates in CRC cells. The up-regulation of XAF1 distinctly increased apoptosis in CRC cells administered by cisplatin (P < 0.001). The XAFl could promoted apoptosis and enhanced chemotherapy sensitivity to cisplatin in CRC cells.