Clinicopathological and prognostic significance of CDH1 hypermethylation in hepatocellular carcinoma: a meta-analysis.

BACKGROUND: The patients with hepatocellular carcinoma (HCC) have poor prognosis due to being diagnosed at late stage or recurrence following surgery. It's critical to identify effective biomarkers that can improve overall diagnosis and treatment of HCC. METHODS: We performed a meta-analysis of all relative studies reporting the clinicopathological significance of CDH1 hypermethylation in HCC by using Review Manager 5.2. A comprehensive literature search was performed in EMBASE, PubMed, Web of Science and Google Scholar databases. Kaplan Meier Plotter online database was used for the determination of correlation between CDH1 mRNA expression and overall survival in patients with HCC. Odds Ratios (OR) with 95% corresponding confidence intervals (CIs) were calculated. A total of 12 relevant studies were included in the meta-analysis with 981 patients. RESULTS: The positive rate of CDH1 hypermethylation was significantly higher in HCC than in normal liver tissue; and the pooled OR was 4.34 with 95% CI 2.50-7.56, P<0.00001. CDH1 promoter in HCC was more frequently hypermethylated compared to the group of chronic liver disease (CLD); OR was 4.83 with 95% CI 2.67-8.72, P<0.00001. However, the rate of CDH1 promoter hypermethylation was not correlated with different grades as well as stages. High CDH1 mRNA expression was significantly correlated to better overall survival in all 231 HCC patients compared to 133 HCC patients with low level CDH1 mRNA expression; HR was 0.6 with 95% CI 0.42-0.85, P=0.0034. CONCLUSION: In summary, CDH1 promoter hypermethylation is a risk factor and promising biomarker for HCC carcinogenesis and diagnosis, as well as a predictor of poor prognosis.

Tongue Coating Microbiota Community and Risk Effect on Gastric Cancer.

Background: Although oral hygiene and health have long been reported to be associated with increased risk of gastric cancer (GC), the direct relationship of oral microbes with the risk of GC have not been evaluated fully. We aimed to test whether tongue coating microbiome was associated with GC risk. Methods: Pyrosequencing of 16S rRNA gene of tongue coating microbiome was used in 57 newly diagnosed gastric adenocarcinomas and 80 healthy controls. Benjamini-Hochberg (BH) was applied for multiple comparison correction. Co-abundance group (CAGs) analysis was adopted. Results: We found that higher relative abundance of Firmicutes, and lower of Bacteroidetes were associated with increased risk of GC. In genus level, Streptococcus trended with a higher risk of GC, the four other genera (Neisseria, Prevotella, Prevotella7, and Porphyromonas) were found to have a decreased risk of GC. Different from overall GC and non-cardia cancer, Alloprevotella and Veillonella trended with the higher risk of cardia cancer. Finally, we analyzed the microbiota by determining CAGs and six clusters were identified. Except the Cluster 2 (mainly Streptococcus and Abiotrophia), the other clusters had an inverse association with GC. Of them, the Cluster 6 (mainly Prevotella and Prevotella7 etc) had a relatively good classification power with 0.76 of AUC. Conclusion: Microbiome in tongue coating may have potential guiding value for early detection and prevention of GC.

Genetic variants in the 3' untranslated region of sFRP1 gene and risk of gastric cancer in a Chinese population.

BACKGROUND: Secreted frizzled-related protein 1 (sFRP1), a negative regulator of the Wnt signaling pathway, is frequently inactivated in human gastric cancer. Genetic variants in the 3' untranslated region (UTR) of the gene may influence the strength of miRNA binding and the regulation of mRNA transcription, affecting the individual's cancer risk. This study aims to investigate the impact of variants in the 3' UTR of sFRP1 on the gastric cancer susceptibility in a Chinese population. PATIENTS AND METHODS: The association between 2 sFRP1 gene variation loci (rs1127379 and rs10088390) with minor allele frequency more than 0.1 in the 3' UTR and gastric cancer risk was assessed in a case-control study including 419 gastric cancer cases and 571 healthy controls. PCR-restriction fragment length polymorphism analysis was used for genotyping; the odds ratio and 95% confidence interval were calculated to estimate the relative risk. RESULTS: Compared with the AA genotype, the GG genotype of rs1127379 was significantly associated with a reduced risk of gastric cancer overall. In the subgroup analysis, the protective effect of the GG genotype was also found for noncardia cancer and intestinal gastric cancer. Furthermore, haplotype analysis showed that the A rs1127379 G rs10088390 haplotype conferred a risk effect for gastric cancer. CONCLUSIONS: Genetic variants at the sFRP1 gene may be involved in gastric tumorigenesis, especially in noncardia and intestinal gastric cancer. Further prospective studies with different ethnicities and large sample sizes are needed to confirm our findings.

Genetic variations of DICKKOPF family genes might not be associated with gastric cancer susceptibility.

BACKGROUND: Recent studies have implicated that members of the DICKKOPF (DKK) were causally involved in large number of human cancers. This study was designed to investigate the relationship between the genetic variations of DKK family genes and the risk of gastric cancer (GC). METHODS: Six SNPs (single nucleotide polymorphisms) of DKK family genes, including rs2241529 in DKK1, rs3733635, rs17037102 and rs419764 in DKK2, rs3206824 in DKK3 and rs2073664 in DKK4, were selected and genotyped by restriction fragment length polymorphism (RFLP) and TaqMan SNP genotyping methods in 409 GC cases and 554 cancer-free controls in the Han population in eastern China. RESULTS: None of the six SNPs achieved significant association with the overall GC risk and stratified analysis by age, gender, smoking status, drinking status, tumor location and pathological classification confirmed these non-significant associations. CONCLUSIONS: Our study indicated that the studied six SNPs of DKKs would not be the risk factors for GC in this Han Chinese population. Studies of larger population for different ethnicities will be needed to warrant our findings.

Regional Arterial Infusion Chemotherapy improves the Pathological Response rate for advanced gastric cancer with Short-term Neoadjuvant Chemotherapy.

To identify clinicopathologic and treatment variables that could predict pathologic tumor response to short-term neoadjuvant chemotherapy (NAC) for patients with locally advanced gastric cancer. A retrospective analysis was conducted of 178 patients who underwent short-term NAC with EOX regimen followed by surgery from January 2008 to December 2010. Neoadjuvant treatment response was evaluated using tumor regression grade. Relationships between pathologic tumor response and clinicopathological factors were evaluated using logistic regression analysis. The benefits of regional arterial infusion chemotherapy were investigated separately. The postoperative pathological response rate was 46.1% (82/178) and 4 patients (2.2%) had complete pathological remission. Pathological response was significantly associated with tumor differentiation (P = 0.008), abnormal a-fetoprotein levels (P = 0.01) and administration approach to chemotherapy (intravenous versus regional arterial infusion chemotherapy) (P = 0.018). Most bone marrow toxicities, vomiting, nausea, alopecia, and fatigue were acceptable. Grade 3/4 toxicities were not commonly observed. The 3-year overall survival (OS) and recurrence free survival (RFS) were 67.0% and 53.0%, respectively. Regional arterial infusion NAC group had significantly better median RFS (48.0 versus 34.0 months) than the intravenous NAC group (P = 0.049). In conclusion, regional arterial infusion NAC can improve the pathological response rate of advanced gastric cancer treated with EOX regimen.

IL-11 Attenuates Liver Ischemia/Reperfusion Injury (IRI) through STAT3 Signaling Pathway in Mice.

BACKGROUND: The protective role of IL-11, an IL-6 family cytokine, has been implicated in ischemia/reperfusion injury (IRI) in the heart and kidney, but its role has not been elucidated in liver IRI. This study was designed to evaluate the effects of IL-11 and its mechanism of action on liver IRI in a mouse model. METHODS: A partial (70%) warm liver IRI was induced by interrupting the artery/portal vein blood supply to the left/middle liver lobes. IL-11 mRNA expression of ischemic liver after reperfusion was analyzed. Signal transducer and activator of transcription 3 (STAT3) was analyzed following IL-11 treatment in vivo and in vitro. Next, IL-11 was injected intraperitoneally (ip) 1 hour before ischemia. Liver injury was assessed based on serum alanine aminotransferase levels and histopathology. Apoptosis and inflammation were also determined in the ischemic liver. To analyze the role of STAT3 in IL-11 treatment, STAT3 siRNA or non-specific (NS) siRNA was used in vitro and in vivo. RESULTS: IL-11 mRNA expression was significantly increased after reperfusion in the ischemic liver. STAT3, as a target of IL-11, was activated in hepatocytes after IL-11 treatment in vivo and in vitro. Next, effects of IL-11/STAT3 signaling pathway were assessed in liver IRI, which showed IL-11 treatment significantly attenuated liver IRI, as evidenced by reduced hepatocellular function and hepatocellular necrosis/apoptosis. In addition, IL-11 treatment significantly inhibited the gene expressions of pro-inflammatory cytokines (TNF-α and IL-10) and chemokines (IP-10 and MCP-1). To determine the role of STAT3 in the hepatoprotective effects of IL-11, STAT3 siRNA or NS siRNA was used prior to IL-11 treatment. The results showed STAT3 knockdown abrogated the protective effects of IL-11 in vitro and in vivo. CONCLUSIONS: This work provides first-time evidence for the protective effect of IL-11 treatment on hepatocyte in liver IRI, through the activation of the STAT3 pathway.

Insulin-like growth factor receptor-1 overexpression is associated with poor response of rectal cancers to radiotherapy.

AIM: To explore the potential correlation between insulin-like growth factor receptor-1 (IGF-1R) expression and rectal cancer radiosensitivity. METHODS: Eighty-seven rectal cancer patients (cTNM I-III) treated in our department between January 2011 and December 2012 were enrolled. All subjects were treated with preoperative radiotherapy and radical resection of rectal carcinoma. Immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR) were performed to detect IGF-1R expression in pre-treatment and postoperative colorectal cancer specimens. Radiosensitivity for rectal cancer specimens was evaluated by observing rectal carcinoma mass regression combined with fibrosis on HE staining, degree of necrosis and quantity of remaining tumor cells. The relative IGF-1R expression was evaluated for association with tumor radiosensitivity. RESULTS: Immunohistochemistry showed diffuse IGF-1R staining on rectal cancer cells with various degrees of signal density. IGF-1R expression was significantly correlated with cTNM staging (P = 0.012) while no significant association was observed with age, sex, tumor size and degree of differentiation (P = 0.424, 0.969, 0.604, 0.642). According to the Rectal Cancer Regression Grades (RCRG), there were 31 cases of RCRG1 (radiation sensitive), 28 cases of RCRG2 and 28 cases of RCRG3 (radiation resistance) in 87 rectal cancer subjects. IGF-1R protein hyper-expression was significantly correlated with a poor response to radiotherapy (P < 0.001, r = 0.401). RT-PCR results from pre-radiation biopsy specimens also showed that IGF-1R mRNA negative group exhibited a higher radiation sensitivity (P < 0.001, r = 0.497). Compared with the pre-radiation biopsy specimens, the paired post-operative specimens showed a significantly increased IGF-1R protein and mRNA expression in the residual cancer cells (P < 0.001, respectively). CONCLUSION: IGF-1R expression level may serve as a predictive biomarker for radiosensitivity of rectal cancer before preoperative radiotherapy.

[Application of regional arterial infusion chemotherapy in short-term neoadjuvant chemotherapy for advanced gastric cancer].

OBJECTIVE: To explore the feasibility of short-term neoadjuvant chemotherapy (NACT) in patients with advanced gastric cancer (AGC), and to compare clinical efficacy of short-term neoadjuvant chemotherapy with different ways. METHODS: Clinical data of 310 AGC patients treated with one course of NACT using EOF regimen(epirubicin, oxaliplatin and fluorouracil plus calcium folinate) in our hospital from January 2008 to December 2011 were retrospectively analyzes. Efficacy was compared between regional arterial infusion chemotherapy and intravenously chemotherapy. RESULTS: All the 310 AGC patients completed one course of NACT and none was interrupted by adverse events. Postoperative pathological remission rate was 33.9% (105/310) and 5 patients (1.6%) had complete pathological remission. The pathologic response rate in the regional arterial infusion chemotherapy group was higher than that in the intravenously chemotherapy group(42.4% vs. 23.6%, P = 0.001). Multivariate analysis revealed that chemotherapy method(HR=1.827, 95% CI:1.006-3.316, P = 0.048) was associated with significantly higher pathologic response. CONCLUSIONS: Pathological response rate is quite low following short-term NACT. Regional arterial infusion chemotherapy with short-term NACT can improve the pathological response rate of advanced gastric cancer.

Growth hormone protects colorectal cancer cells from radiation by improving the ability of DNA damage repair.

The present study aimed to examine the effects of recombinant human growth hormone (rhGH) on the sensitivity of a colorectal cancer cell line to radiotherapy, and to investigate its association with DNA damage and repair. Flow cytometry and immunofluorescence were employed to detect growth hormone receptor (GHR) expression in nine human colorectal cancer cell lines. A colony forming assay was performed to measure the colorectal cancer cell proliferation post­radiotherapy, as an indicator of radiotherapy sensitivity. The comet assay results were interpreted as an indicator of radiotherapy­induced DNA damage, and growth arrest and DNA damage 45 (GADD45) and apurinic/apyrimidinic endonuclease (APEN) protein expression were quantified with western blot analysis from the same cell lines. The results demonstrated that the colony­forming efficiency (CFE) was significantly increased in HCT­8 cells subject to radiotherapy and rhGH pretreatment compared with the cells treated with radiotherapy alone, in a dose­dependent manner (0­100 mg/l). This effect was enhanced under high doses of radiation (8 Gy; 52.1±2.9 vs. 21.0±2.7; P<0.001) and was ameliorated with GHR neutralizing antibody exposure. By contrast, rhGH pre­incubation did not change the colony formation rate in GHR(­) LOVO cells. rhGH intervention reduced the early HCT­8 cell DNA damage (21.53±2.88 vs. 36.56±3.93; P=0.003) as well as the following plateau phase, compared with cells treated with radiotherapy alone (5.5±0.42 vs. 9.07±0.84; P=0.012). rhGH upregulated GADD45 and APEN protein expression, which is associated with cellular stress responses and DNA damage repair (P=0.007). The results suggest that rhGH is able to protect colorectal cancer cells from radiation through the interaction with GHR, which is associated with the promotion of DNA damage repair activity.

Inhibition of Aurora B by CCT137690 sensitizes colorectal cells to radiotherapy.

Colorectal cancer is the third most commonly diagnosed cancer worldwide. Although surgery remains the best treatment for this disease, adjuvant chemotherapy and radiotherapy are also very important in clinical practice. However, the notorious refractory lack of responses to radiochemotherapy greatly limits the application of radiochemotherapy in the context of colorectal cancer.There is a growing interest in the role that Aurora B may play in colorectal cancer cell survival as well as other cancer subtypes. In the current study, we sought to ascertain whether blocking of Aurora B signaling machinery by a small molecule inhibitor, CCT137690, could synergize radiation-induced colorectal cancer cell death. Results showed that CCT137690 increases the sensitivity of SW620 cells to radiation. Mechanistic studies revealed that Aurora B-Survivin pathway may be involved in this synergistic effect.Taken together, our results for the first time show that Aurora B inhibition and radiation exert a synergistic effect, resulting in enhanced colorectal cancer cell death. This synergistic effect is clinically relevant as lower doses of radiation could be used for cancer treatment, and could provide significant clinical benefits in terms of colorectal cancer management, while reducing unwanted side-effects.

Blockade of inflammatory responses by a small-molecule inhibitor of the Rac activator DOCK2.

Tissue infiltration of activated lymphocytes is a hallmark of transplant rejection and organ-specific autoimmune diseases. Migration and activation of lymphocytes depend on DOCK2, an atypical Rac activator predominantly expressed in hematopoietic cells. Although DOCK2 does not contain Dbl homology domain typically found in guanine nucleotide exchange factors, DOCK2 mediates the GTP-GDP exchange reaction for Rac through its DHR-2 domain. Here, we have identified 4-[3'-(2″-chlorophenyl)-2'-propen-1'-ylidene]-1-phenyl-3,5-pyrazolidinedione (CPYPP) as a small-molecule inhibitor of DOCK2. CPYPP bound to DOCK2 DHR-2 domain in a reversible manner and inhibited its catalytic activity in vitro. When lymphocytes were treated with CPYPP, both chemokine receptor- and antigen receptor-mediated Rac activation were blocked, resulting in marked reduction of chemotactic response and T cell activation. These results provide a rational of and a chemical scaffold for development of the DOCK2-targeting immunosuppressant.

Selective control of type I IFN induction by the Rac activator DOCK2 during TLR-mediated plasmacytoid dendritic cell activation.

Plasmacytoid dendritic cells (pDCs) play a key role in antiviral immunity, but also contribute to the pathogenesis of certain autoimmune diseases, by producing large amounts of type I IFNs. Although activation of pDCs is triggered by engagement of nucleotide-sensing toll-like receptors (TLR) 7 and 9, type I IFN induction additionally requires IkappaB kinase (IKK) alpha-dependent activation of IFN regulatory factor (IRF) 7. However, the signaling pathway mediating IKK-alpha activation is poorly defined. We show that DOCK2, an atypical Rac activator, is essential for TLR7- and TLR9-mediated IFN-alpha induction in pDCs. We found that the exposure of pDCs to nucleic acid ligands induces Rac activation through a TLR-independent and DOCK2-dependent mechanism. Although this Rac activation was dispensable for induction of inflammatory cytokines, phosphorylation of IKK-alpha and nuclear translocation of IRF-7 were impaired in Dock2-deficient pDCs, resulting in selective loss of IFN-alpha induction. Similar results were obtained when a dominant-negative Rac mutant was expressed in wild-type pDCs. Thus, the DOCK2-Rac signaling pathway acts in parallel with TLR engagement to control IKK-alpha activation for type I IFN induction. Owing to its hematopoietic cell-specific expression, DOCK2 may serve as a therapeutic target for type I IFN-related autoimmune diseases.

A novel role for DYX1C1, a chaperone protein for both Hsp70 and Hsp90, in breast cancer.

AIMS: With three consecutive tetratricopeptide repeat (TPR) motifs at its C-terminus essential for neuronal migration, and a p23 domain at its N-terminus, DYX1C1 was the first gene proposed to have a role in developmental dyslexia. In this study, we attempted to identify the potential interaction of DYX1C1 and heat shock protein, and the role of DYX1C1 in breast cancer. MAIN METHODS: GST pull-down, a yeast two-hybrid system, RT-PCR, site-directed mutagenesis approach. KEY FINDINGS: Our study initially confirmed DYX1C1, a dyslexia related protein, could interact with Hsp70 and Hsp90 via GST pull-down and a yeast two-hybrid system. And we verified that EEVD, the C-terminal residues of DYX1C1, is responsible for the identified association. Further, DYX1C1 mRNA was significantly overexpressed in malignant breast tumor, linking with the up-regulated expression of Hsp70 and Hsp90. SIGNIFICANCE: These results suggest that DYX1C1 is a novel Hsp70 and Hsp90-interacting co-chaperone protein and its expression is associated with malignancy.

Sequential regulation of DOCK2 dynamics by two phospholipids during neutrophil chemotaxis.

During chemotaxis, activation of the small guanosine triphosphatase Rac is spatially regulated to organize the extension of membrane protrusions in the direction of migration. In neutrophils, Rac activation is primarily mediated by DOCK2, an atypical guanine nucleotide exchange factor. Upon stimulation, we found that DOCK2 rapidly translocated to the plasma membrane in a phosphatidylinositol 3,4,5-trisphosphate-dependent manner. However, subsequent accumulation of DOCK2 at the leading edge required phospholipase D-mediated synthesis of phosphatidic acid, which stabilized DOCK2 there by means of interaction with a polybasic amino acid cluster, resulting in increased local actin polymerization. When this interaction was blocked, neutrophils failed to form leading edges properly and exhibited defects in chemotaxis. Thus, intracellular DOCK2 dynamics are sequentially regulated by distinct phospholipids to localize Rac activation during neutrophil chemotaxis.

A novel mouse model of human breast cancer stem-like cells with high CD44+CD24-/lower phenotype metastasis to human bone.

BACKGROUND: A satisfactory animal model of breast cancer metastasizing to bone is unavailable. In this study, we used human breast cancer stem-like cells and human bone to build a novel "human-source" model of human breast cancer skeletal metastasis. METHODS: Human breast cancer stem-like cells, the CD44+/CD24-/lower subpopulation, was separated and cultured. Before injection with the stem-like cells, mice were implanted with human bone in the right or left dorsal flanks. Animals in Groups A, B, and C were injected with 1 x 10(5), 1 x 10(6) human breast cancer stem-like cells, and 1 x 10(6) parental MDA-MB-231 cells, respectively. A positive control group (D) without implantation of human bone was also injected with 1 x 10(6) MDA-MB-231 cells. Immunohistochemistry was performed for determination of CD34, CD105, smooth muscle antibody, CD44, CD24, cytokine, CXC chemokine receptor-4 (CXCR4), and osteopontin (OPN). mRNA levels of CD44, CD24, CXCR4, and OPN in bone metastasis tissues were analyzed by real-time quantitative polymerase chain reaction (PCR). RESULTS: Our results demonstrated that cells in implanted human bones of group B, which received 1 x 10(6) cancer stem-like cells, stained strongly positive for CD44, CXCR4, and OPN, whereas those of other groups showed no or minimum staining. Moreover, group B had the highest incidence of human bone metastasis (77.8%, P = 0.0230) and no accompaniment of other tissue metastasis. The real-time PCR showed an increase of CD44, CXCR4, and OPN mRNA in metastatic bone tissues in group B compared with those of groups C and D, however the expression of CD24 mRNA in group B were the lowest. CONCLUSIONS: In the novel "human source" model of breast cancer, breast cancer stem-like cells demonstrated a higher human bone-seeking ability. Its mechanism might be related to the higher expressions of CD44, CXCR4, and OPN, and the lower expression of CD24 in breast cancer stem-like cells.

A testis-specific and testis developmentally regulated tumor protein D52 (TPD52)-like protein TPD52L3/hD55 interacts with TPD52 family proteins.

Tumor protein D52-like proteins (TPD52) are small coiled-coil motif bearing proteins that were first identified in breast cancer. TPD52 and related proteins have been implicated in cell proliferation, apoptosis, and vesicle trafficking. To date, three human TPD52 members had been identified, named hD52 (TPD52), hD53 (TPD52L1), and hD54 (TPD52L2). The most important characteristic of the protein family is a highly conserved coiled-coil motif that is required for homo- and heteromeric interaction with other TPD52-like proteins. Herein, we identified a novel TPD52-like sequence (TPD52L3, or hD55) in human testis using cDNA microarray. Sequence analysis of the deduced protein suggests that hD55 contains a coiled-coil motif and is highly conserved compared with other TPD52-like sequences. Yeast two-hybrid and GST pull-down assays revealed that hD55 interacts with hD52, hD53, hD54, and itself. cDNA microarray detection found that hD55 was expressed at 5.6-fold higher levels in adult testis than in fetal testis. Additionally, the expression profile shows that hD55 is testis-specific, indicating a potential role for hD55 in testis development and spermatogenesis.