Expressions of hypoxia-inducible factor-1 and epithelial cell adhesion molecule are linked with aggressive local recurrence of hepatocellular carcinoma after radiofrequency ablation therapy

BACKGROUND

Radiofrequency ablation (RFA) is a widely used therapy for hepatocellular carcinoma (HCC). Several reports have demonstrated the aggressive local recurrence of HCC after RFA, suggesting that induction of further malignant transformation of HCC has occurred.

METHODS

Eighty-eight (88) patients with HCC who underwent hepatic resection were included in this study. Hepatectomy was indicated for local recurrence of HCC after RFA (n = 10, RFA group) and for HCC without prior RFA (n = 78, non-RFA group). Clinicopathological data and the patient's prognosis after hepatectomy were compared between the two groups. Expression levels of hypoxia-inducible factor-1 (HIF-1), epithelial cell adhesion molecule (EpCAM), CD44, and vascular endothelial growth factor messenger RNA (mRNA) in the tumor tissues were also examined.

RESULTS

The RFA group showed higher frequency of portal vein invasion and less tumor differentiation compared with the non-RFA group (p < 0.05). Overall and disease-free survival rates in the RFA group were significantly worse than those in the non-RFA group (p < 0.05). HIF-1 and EpCAM mRNA expression levels in the RFA group were significantly higher than those in the non-RFA group (p < 0.05).

CONCLUSIONS

These results suggest that local HCC recurrence after RFA shows an aggressive tumor phenotype and poor prognosis through the enhanced expressions of HIF-1 and EpCAM in the residual HCC tumors after insufficient or sub-lethal treatment by RFA.

Comparison of long-term prognosis of laparoscopy-assisted gastrectomy and conventional open gastrectomy with special reference to D2 lymph node dissection

BACKGROUND

Laparoscopy-assisted gastrectomy (LAG) is becoming widely used for early gastric cancer. However, how the curability and long-term prognosis of LAG and open gastrectomy (OG) for early and advanced gastric cancer compare remains unclear. This study assessed short- and long-term outcomes after LAG with lymph node dissection in early and advanced gastric cancer.

METHODS

A total of 332 patients who underwent LAG or OG for early and advanced gastric cancer from January 2001 through December 2010 were reviewed retrospectively. The mean operating time, estimated mean blood loss, number of dissected lymph nodes, and survival rates were compared between LAG and OG for early and advanced gastric cancer.

RESULTS

Overall, 47.6% (158/332) of patients underwent LAG; D1, D1+ lymph node dissection was carried out in 77.2%, with D2 dissection in 22.8%. Only one patient required conversion to OG. Comparing LAG and OG with D1, D1+ lymph node dissection for early gastric cancer (EGC), mean operating time was significantly longer, estimated mean blood loss was significantly smaller, and the average number of retrieved lymph nodes was significantly greater with LAG. The rate of specific postoperative morbidity was 17.2% for LAG patients and 25.0% for OG patients, with no postoperative mortality. Survival and recurrence rates were not significantly different. Comparing LAG and OG with D2 lymph node dissection for advanced gastric cancer (AGC), mean operating time was significantly longer and estimated mean blood loss was significantly smaller with LAG, while the average number of retrieved lymph nodes, specific postoperative morbidity and mortality, and survival and recurrence rates were not significantly different.

CONCLUSIONS

LAG with D1, D1+ lymph node dissection for EGC is safe and equivalent to open gastrectomy in curability. Moreover, LAG with D2 lymph node dissection for AGC is comparable to OG with D2 lymph node dissection with regard to short- and long-term results.

Epigallocatechin-3-gallate Enhances Radiation Sensitivity in Colorectal Cancer Cells Through Nrf2 Activation and Autophagy

BACKGROUND/AIM

Epigallocatechin-3-gallate (EGCG) is a major polyphenolic component of green tea. EGCG plays a potential role in radio-sensitizing cancer cells. The combined effect of EGCG and radiation was investigated in a colorectal cancer cell line, focusing on nuclear factor (erythroid-derived 2)-like 2 (Nrf2) autophagy signalling.

MATERIALS AND METHODS

HCT-116 cells were treated with 12.5 μM EGCG for different periods of time, 2 Gy radiation, or both. Cell viability was determined with the WST-8 assay. The number of colonies was determined with the colony formation assay. mRNA expression of LC3 and caspase-9 was analyzed with quantitative real-time polymerase chain reaction.

RESULTS

Combination treatment with EGCG and radiation significantly decreased the growth of HCT-116 cells. The number of colonies was reduced to 34.2% compared to the control group. Immunofluorescence microscopy images showed that nuclear translocation of Nrf2 was significantly increased when cells were treated with the combination of EGCG and radiation compared to the control and single-treatment groups. Combined treatment with EGCG and radiation significantly induced LC3 and caspase-9 mRNA expression.

CONCLUSION

EGCG increased the sensitivity of colorectal cancer cells to radiation by inhibiting cell proliferation and inducing Nrf2 nuclear translocation and autophagy.

Treatment with dimethyl fumarate ameliorates liver ischemia/reperfusion injury

AIM

To investigate the hypothesis that treatment with dimethyl fumarate (DMF) may ameliorate liver ischemia/reperfusion injury (I/RI).

METHODS

Rats were divided into 3 groups: sham, control (CTL), and DMF. DMF (25 mg/kg, twice/d) was orally administered for 2 d before the procedure. The CTL and DMF rats were subjected to ischemia for 1 h and reperfusion for 2 h. The serum alanine aminotransferase (ALT) and malondialdehyde (MDA) levels, adenosine triphosphate (ATP), NO × metabolites, anti-oxidant enzyme expression level, anti-inflammatory effect, and anti-apoptotic effect were determined.

RESULTS

Histological tissue damage was significantly reduced in the DMF group (Suzuki scores: sham: 0 ± 0; CTL: 9.3 ± 0.5; DMF: 2.5 ± 1.2; sham vs CTL, P < 0.0001; CTL vs DMF, P < 0.0001). This effect was associated with significantly lower serum ALT (DMF 5026 ± 2305 U/L vs CTL 10592 ± 1152 U/L, P = 0.04) and MDA (DMF 18.2 ± 1.4 μmol/L vs CTL 26.0 ± 1.0 μmol/L, P = 0.0009). DMF effectively improved the ATP content (DMF 20.3 ± 0.4 nmol/mg vs CTL 18.3 ± 0.6 nmol/mg, P = 0.02), myeloperoxidase activity (DMF 7.8 ± 0.4 mU/mL vs CTL 6.0 ± 0.5 mU/mL, P = 0.01) and level of endothelial nitric oxide synthase expression (DMF 0.38 ± 0.05-fold vs 0.17 ± 0.06-fold, P = 0.02). The higher expression levels of anti-oxidant enzymes (catalase and glutamate-cysteine ligase modifier subunit and lower levels of key inflammatory mediators (nuclear factor-kappa B and cyclooxygenase-2 were confirmed in the DMF group.

CONCLUSION

DMF improved the liver function and the anti-oxidant and inflammation status following I/RI. Treatment with DMF could be a promising strategy in patients with liver I/RI.

Hypomethylation of long interspersed nuclear element-1 (LINE-1) is associated with poor prognosis via activation of c-MET in hepatocellular carcinoma

BACKGROUND

Long interspersed nuclear element-1 (LINE-1) methylation status, representing global DNA methylation levels, is associated with patient prognosis in several types of cancer. This study was designed to examine the prognostic significance of LINE-1 methylation in patients with hepatocellular carcinoma (HCC) and the possible mechanisms related to oncogene activation.

METHODS

Seventy-five HCC patients who underwent hepatectomy between 2006 and 2012 were enrolled in this study. Quantitative pyrosequencing was performed to quantify the methylation level of three CpG sites in the LINE-1 promoter. Clinicopathological variables and prognosis were compared between LINE-1 hypo- and hypermethylation groups. LINE-1-inserted c-MET (L1-MET) gene expression and its correlation with LINE-1 methylation levels also were analyzed.

RESULTS

LINE-1 was significantly hypomethylated in tumor tissues compared with nontumor tissues (48.3 ± 12.2 % vs. 68.2 ± 2.0 %, respectively, p < 0.0001). LINE-1 hypomethylation was not associated with any clinicopathological factors in HCC patients, except sex (p < 0.05). However, patients with LINE-1 hypomethylation exhibited significantly poorer outcome, and multivariate analysis revealed that LINE-1 hypomethylation was an independent risk factor for overall survival (hazard ratio (HR) = 6.1, p = 0.031) and disease-free survival (HR = 2.34, p = 0.045). L1-MET expression was significantly higher in tumor tissues (p < 0.01). L1-MET expression levels were inversely correlated with LINE-1 methylation levels, and positively correlated with c-MET expression (p < 0.05). Furthermore, higher c-MET protein expression was observed in the LINE-1 hypomethylated tumor tissues compared with hypermethylated tumor tissues (p = 0.032).

CONCLUSIONS

LINE-1 hypomethylation is significantly associated with poor prognosis in patients with HCC, possibly due to activation of c-MET expression.

Programmed Cell Death Ligand 1 Expression Is an Independent Prognostic Factor in Colorectal Cancer

BACKGROUND/AIM

Programmed cell death protein 1 (PD-1)/ programmed cell death ligand 1(PD-L1) axis is associated with immune tolerance via inhibition of T cell activation. The aim of this study was to clarify the significance of PD-1 and PD-L1 expressions and analyze the relationships between PD-1, PD-L1, transforming growth factor-β (TGF-β) and Forkhead box P3 (Foxp3) expressions in colorectal cancer (CRC).

PATIENTS AND METHODS

A total of 116 patients who underwent curative colectomy for stage II/III CRC were included in the study. PD-1, PD-L1, TGF-β, and Foxp3 expressions were examined by immunohistochemistry and related to prognostic factors by Kaplan-Meier.

RESULTS

PD-1 expression was correlated with PD-L1, TGF-β, and Foxp3 expressions. Overall survival rates were significantly poorer in the PD-1 and PD-L1-positive groups. Multivariate analysis showed that PD-L1-positive is an independent risk factor. Disease-free survival (DFS) was tended in the PD-L1-positive group. The group with double-positive expression had significantly poorer prognosis.

CONCLUSION

PD-1 and PD-L1 expressions were associated with a poor prognosis and correlated with TGF-β and Foxp3 expressions in patients with CRC.

The BAFF/NFκB axis is crucial to interactions between sorafenib-resistant HCC cells and cancer-associated fibroblasts

The tumor microenvironment affects malignancy in hepatocellular carcinoma (HCC) cells, and cancer-associated fibroblasts (CAFs) play an important role in the microenvironment. As recent studies indicated a difference between CAFs isolated from chemoresistant and non-resistant cancer tissues, therefore we investigated the intracellular mechanism in resistant HCC co-cultured CAFs and interactions between these CAFs with cancer cells. We established a sorafenib-resistant (SR) Huh7 (human HCC) cell line, and characterized it with cytokine assays, then developed CAFs by co-culturing human hepatic stellate cells with resistant or parental Huh7 cells. The 2 types of CAFs were co-cultured with parental Huh7 cells, thereafter the cell viability of these Huh7 cells was checked under sorafenib treatment. The SR Huh7 (Huh7^SR ) cells expressed increased B-cell activating factor (BAFF), which promoted high expression of CAF-specific markers in Huh7^SR -co-cultured CAFs, showed activated BAFF, BAFF-R, and downstream of the NFκB-Nrf2 pathway, and aggravated invasion, migration, and drug resistance in co-cultured Huh7 cells. When we knocked down BAFF expression in Huh7^SR cells, the previously increased malignancy and BAFF/NFκB axis in Huh7^SR -co-cultured CAFs reversed, and enhanced chemoresistance in co-cultured Huh7 cells returned as well. In conclusion, the BAFF/NFκB pathway was activated in CAFs co-cultured with cell-culture medium from resistant Huh7, which promoted chemoresistance, and increased the malignancy in co-cultured non-resistant Huh7 cells. This suggests that the BAFF/NFκB axis in CAFs might be a potential therapeutic target in chemoresistance of HCC.

Blue light-emitting diodes induce autophagy in colon cancer cells by Opsin 3

Background

Light emitting-diodes (LED) have various effects on living organisms and recent studies have shown the efficacy of visible light irradiation from LED for anticancer therapies. However, the mechanism of LED's effects on cancer cells remains unclear. The aim of the present study was to investigate the effects of LED on colon cancer cell lines and the role of photoreceptor Opsin 3 (Opn3) on LED irradiation in vitro.

Methods

Human colon cancer cells (HT-29 or HCT-116) were seeded onto laboratory dishes and irradiated with 465-nm LED at 30 mW/cm² for 30 minutes. Cell Counting Kit-8 was used to measure cell viability, and apoptosis and caspase 3/8 expression were evaluated by AnnexinV/PI and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Autophagy and expression of LC-3 and beclin-1 were also evaluated by autophagy assays, RT-PCR and Western blotting. We further tested Opn3 knockdown by Opn3 siRNA and the G_i/o G-protein inhibitor NF023 in these assays.

Results

Viability of HT-29 and HCT-116 cells was lower in 465-nm LED-irradiated cultures than in control cultures. LC-3 and beclin-1 expressions were significantly higher in LED-irradiated cultures, and autophagosomes were detected in irradiated cells. The reductive effect of cancer cell viability following blue LED irradiation was reversed by Opn3 knockdown or NF023 treatment. Furthermore, increased LC-3 and beclin-1 expression that resulted from blue LED irradiation was suppressed by Opn3 knockdown or NF023 treatment.

Conclusion

Blue LED irradiation suppressed the growth of colon cancer cells and Opn3 may play an important role as a photoreceptor.

Elevated Preoperative Serum CEA Level Is Associated with Poor Prognosis in Patients with Hepatocellular Carcinoma Through the Epithelial-Mesenchymal Transition

BACKGROUND

Serum carcinoembryonic antigen (CEA) is used as an indicator of tumor progression in a variety of carcinomas. A subset of patients with hepatocellular carcinoma (HCC) exhibit increased serum CEA level, but the significance of this is unclear. In this study, we investigated the prognosis of patients with HCC with increased serum CEA, and explored the correlations with expression of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and epithelial-mesenchymal transition (EMT) and tumor angiogenesis.

MATERIALS AND METHODS

One hundred and twenty-three patients with HCC who underwent radical resection were divided into two groups according to a cut-off value of 5.0 ng/ml for serum CEA: high (n=24) and normal (n=99) groups. We compared the clinicopathological factors with serum CEA levels and its correlations with CEACAM1 expression, EMT-related factors and microvessel density (MVD) of tumor tissues by immunohistochemistry.

RESULTS

In the high CEA group, the disease-free survival (DFS) rate was significantly worse than in the normal CEA group. Multivariate analysis revealed that a high CEA level was an independent factor predictive of recurrence. Furthermore, increased serum CEA levels were positively correlated with CEACAM1 expression. Moreover, CEACAM1 expression was positively correlated with expression of EMT-related factors and MVD of tumor tissues.

CONCLUSION

Increased serum CEA level reflected CEACAM1 expression and was an independent factor predictive of recurrence in HCC through EMT and tumor angiogenesis.

Homing effect of adipose-derived stem cells to the injured liver: the shift of stromal cell-derived factor 1 expressions

BACKGROUND

Whether systemically transplanted human adipose-derived stem cells (ADSCs) homed to the injured liver in nude mice under stress with subsequent hepatectomy (Hx) and ischemia-reperfusion (I/R) was investigated in the present study. The types of cells in the liver that were involved in the homing of ADSCs were clarified, with focus on the stromal-derived factor-1 (SDF-1)/C-X-C chemokine receptor type 4 (CXCR-4) axis.

METHODS

Adipose-derived stem cells were transplanted intravenously immediately after 70% Hx and I/R. ADSCs were traced by in vivo imaging for 24 h after transplantation and ADSCs were histologically detected in the liver. SDF-1 and CXCR-4 expressions in the liver were evaluated by real time RT-PCR. The immunohistochemical analysis of SDF-1 was also performed to identify SDF-1 expressing cells in the liver.

RESULTS

Adipose-derived stem cells were found in various organs immediately following transplantation and almost accumulated in remnant liver or spleen at 6 h after transplantation. ADSCs were also histologically revealed in the harvested liver. Hx and I/R injury significantly enhanced SDF-1 expressions regardless of ADSCs transplantation, and only ADSC transplantation increased CXCR-4 expressions. The predominant SDF-1 positive cells in the liver were equally identified in parenchymal and non-parenchymal cells at 6 h, but shifted to non-parenchymal cells at 24 h after transplantation.

CONCLUSIONS

Systemically transplanted ADSCs homed to the injured liver after transplantation, possibly based on the mechanisms of SDF-1/CXCR-4 axis. Therefore, systemic transplantation might be an effective and practical route for the transplantation of ADSCs.

Dimethyl Fumarate Alleviates Dextran Sulfate Sodium-Induced Colitis, through the Activation of Nrf2-Mediated Antioxidant and Anti-inflammatory Pathways

Oxidative stress and chronic inflammation play critical roles in the pathogenesis of ulcerative colitis (UC) and inflammatory bowel diseases (IBD). A previous study has demonstrated that dimethyl fumarate (DMF) protects mice from dextran sulfate sodium (DSS)-induced colitis via its potential antioxidant capacity, and by inhibiting the activation of the NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome. This study aims to clarify the nuclear factor erythroid 2-related factor 2/antioxidant responsive element (Nrf2/ARE) pathway pharmacological activation and anti-inflammatory effect by DMF, through focusing on other crucial antioxidant enzymes and inflammatory mediator, including glutamate-cysteine ligase catalytic subunit (GCLC), glutathione peroxidase (GPX) and cyclooxygenase-2 (COX-2), in a DSS-induced colitis mouse model. The oral administration of DMF attenuated the shortening of colons and alleviated colonic inflammation. Furthermore, the expression of key antioxidant enzymes, including GCLC and GPX, in the colonic tissue were significantly increased by DMF administration. In addition, protein expression of the inflammatory mediator, COX-2, was reduced by DMF administration. Our results suggest that DMF alleviates DSS-induced colonic inflammatory damage, likely via up-regulating GCLC and GPX and down-regulating COX-2 protein expression in colonic tissue.

Dimethyl fumarate protects pancreatic islet cells and non-endocrine tissue in L-arginine-induced chronic pancreatitis

Background

Chronic pancreatitis (CP) is a progressive disorder resulting in the destruction and fibrosis of the pancreatic parenchyma which ultimately leads to impairment of the endocrine and exocrine functions. Dimethyl Fumarate (DMF) was recently approved by FDA for treatment of patients with multiple sclerosis. DMF's unique anti-oxidant and anti-inflammatory properties make it an interesting drug to test on other inflammatory conditions. This study was undertaken to determine the effects of DMF on islet cells and non-endocrine tissue in a rodent model of L-Arginine-induced CP.

Methods

Male Wistar rats fed daily DMF (25 mg/kg) or vehicle by oral gavage were given 5 IP injections of L-Arginine (250 mg/100 g×2, 1 hr apart). Rats were assessed with weights and intra-peritoneal glucose tolerance tests (IPGTT, 2 g/kg). Islets were isolated and assessed for islet mass and viability with flow cytometry. Non-endocrine tissue was assessed for histology, myeloperoxidase (MPO), and lipid peroxidation level (MDA). In vitro assessments included determination of heme oxygenase (HO-1) protein expression by Western blot.

Results

Weight gain was significantly reduced in untreated CP group at 6 weeks. IPGTT revealed significant impairment in untreated CP group and its restoration with DMF therapy (P <0.05). Untreated CP rats had pancreatic atrophy, severe acinar architectural damage, edema, and fatty infiltration as well as elevated MDA and MPO levels, which were significantly improved by DMF treatment. After islet isolation, the volume of non-endocrine tissue was significantly smaller in untreated CP group. Although islet counts were similar in the two groups, islet viability was significantly reduced in untreated CP group and improved with DMF treatment. In vitro incubation of human pancreatic tissue with DMF significantly increased HO-1 expression.

Conclusion

Administration of DMF attenuated L-Arginine-induced CP and islet function in rats. DMF treatment could be a possible strategy to improve clinical outcome in patients with CP.

Senescence-related genes possibly responsible for poor liver regeneration after hepatectomy in elderly patients

BACKGROUND AND AIM

Liver regeneration likely decreases with age by an, as yet, incompletely understood mechanism, restricting the extent of hepatectomy. We therefore analyzed the effect of aging on liver regeneration and investigated mechanisms associate with poor regeneration of human liver.

METHODS

We assessed 130 patients who underwent hepatectomy at our institute between 2005 and 2012. The patients were divided into two groups, a younger (age < 65 years, n = 59) and an older (age > 65 years, n = 71) group. The expression of hepatocyte growth factor (HGF), its ligand Met, and the senescence-related genes p16, SIRT1 and SMP30 were assessed by qRT-PCR. Simulated preoperative and 1 week and 6 month postoperative liver volumes were evaluated in 11 younger and 11 older patients using a 3D simulation imaging system. Regenerated liver volumes were calculated and compared with clinicopathological factors, and correlations between liver regeneration and gene expression were calculated.

RESULTS

HGF and Met expression was significantly lower, and p16 expression significantly higher in older than in younger patients (P < 0.05 each). Mean increases in liver volume after 6 months were significantly greater in younger than in older patients (396.5 mL, 45.6% vs 159.4 mL, 23.3%, P < 0.05) but did not differ significantly at 1 week. Furthermore, p16 expression was negatively correlated with liver regeneration in older patients (R = -0.67, P < 0.05).

CONCLUSION

Poor liver regeneration in older patients may be associated with the upregulation of senescence-related genes, such as p16, and the downregulation of regeneration-promoting genes, such as HGF and Met.

Benefits of simultaneous laparoscopic resection of primary colorectal cancer and liver metastases

INTRODUCTION

Recently, consensus on the optimal strategy for resectable synchronous colorectal liver metastases (LM) seems to have shifted toward simultaneous resection. However, there are still relatively few reports about simultaneous laparoscopic resection. The aim of this study is to evaluate the outcomes of patients who underwent simultaneous laparoscopic resection.

METHODS

We evaluated 14 patients who underwent simultaneous resection of primary colorectal cancer and LM in our hospital from 2004 to 2012. Patients were selected by matched pair analysis based on the number of LM (≤4) and tumor size (≤5 cm). We divided them into two groups: the simultaneous laparoscopic resection of primary colorectal cancer and LM (Lap-S) group (n = 7) and the simultaneous open resection of primary colorectal cancer and LM (Open-S) group (n = 7). Clinical and oncologic outcomes were compared between the groups.

RESULTS

The Lap-S patients were significantly older than the Open-S patients. The mean operative times of Lap-S and Open-S were 472 min and 466 min, respectively. The mean blood loss was significantly smaller in the Lap-S group (153 mL) than in the Open-S group (496 mL). There was no surgical mortality in either group. The incidence of postoperative complications in the Lap-S and Open-S groups was 12.3% and 33.0%, respectively. The mean postoperative hospital stay was significantly shorter in the Lap-S group (16 days) than in the Open-S group (36 days). There was no significant difference in long-term survival between the two groups.

CONCLUSION

Lap-S patients had equivalent long-term outcomes to Open-S patients. Therefore, given its technical feasibility and safety, Lap-S may be one of the most promising options in selected patients.

Nrf2 signaling promotes cancer stemness, migration, and expression of ABC transporter genes in sorafenib-resistant hepatocellular carcinoma cells

Background and aim

As a multiple tyrosine kinase inhibitor, sorafenib is widely used to treat hepatocellular carcinoma (HCC), but patients frequently face resistance problems. Because the mechanism controlling sorafenib-resistance is not well understood, this study focused on the connection between tumor characteristics and the Nrf2 signaling pathway in a sorafenib-resistant HCC cell line.

Methods

A sorafenib-resistant HCC cell line (Huh7) was developed by increasing the dose of sorafenib in the culture medium until the target concentration was reached. Cell morphology, migration/invasion rates, and expression of stemness-related and ATP-binding cassette (ABC) transporter genes were compared between sorafenib-resistant Huh7 cells and parental Huh7 cells. Next, a small interfering RNA was used to knock down Nrf2 expression in sorafenib-resistant Huh7 cells, after which cell viability, stemness, migration, and ABC transporter gene expression were examined again.

Results

Proliferation, migration, and invasion rates of sorafenib-resistant Huh7 cells were significantly increased relative to the parental cells with or without sorafenib added to the medium. The expression levels of stemness markers and ABC transporter genes were up-regulated in sorafenib-resistant cells. After Nrf2 was knocked down in sorafenib-resistant cells, cell migration and invasion rates were reduced, and expression levels of stemness markers and ABC transporter genes were reduced.

Conclusion

Nrf2 signaling promotes cancer stemness, migration, and expression of ABC transporter genes in sorafenib-resistant HCC cells.

Role of thrombospondin-1 expression in colorectal liver metastasis and its molecular mechanism

BACKGROUND

Thrombospondin-1 (THBS-1), a glycoprotein, is an endogenous inhibitor of angiogenesis and tumor growth. In this study, we investigated the clinical role and mechanism of THBS-1 expression in colorectal liver metastases, focusing on the relationships between its expression and tumor growth, epithelial-mesenchymal transition (EMT), and expression of other relevant molecules.

METHODS

Ninety-four patients who initially underwent curative hepatic resection were enrolled in this study and correlations between expression of THBS-1 (THBS-1 high [n = 35] and THBS-1 low [n = 59]) and tumor growth, Ki-67 labeling index (Ki-67 LI), expression of other relevant molecules, and microvessel density (MVD) investigated.

RESULTS

THBS-1 low expression correlated with more advanced grade of liver and lymph node metastases and significantly worse overall survival than strong THBS-1 expression (3-year survival: 96.7% vs. 65.4%, P < 0.01). Multivariate analysis identified THBS-1 low expression as an independent prognostic factor (HR 2.82, 95% CI 1.21-7.71, P = 0.01). THBS-1 low expression correlated positively with high Ki-67 LI (P < 0.05) and inversely with E-cadherin (P < 0.05) and hypoxia inducible factor-1α (HIF-1α) expression (P < 0.05); THBS-1 expression and MVD were not significantly correlated.

CONCLUSIONS

Low THBS-1 expression may be an independent poor prognostic factor that affects tumor growth and EMT acquisition. Additionally, THBS-1 may be regulated by the HIF-1 pathway.

Role of Fbxw7 expression in hepatocellular carcinoma and adjacent non-tumor liver tissue

BACKGROUND AND AIM

Fbxw7 is a tumor suppressor gene through ubiquitination and degradation of multiple oncoproteins. Loss of Fbxw7 expression is frequently observed in various human cancers. In the present study, we examined the role of Fbxw7 expression in both non-tumor liver tissues and tumor tissues on clinicopathological significance.

METHODS

Sixty-six patients with hepatocellular carcinoma (HCC), who underwent hepatectomy, were divided into two groups: high and low gene-expression group, based on the Fbxw7 expression level. We compared the clinicopathological factors between the high expression and low expression groups in both tumor and non-tumor tissues.

RESULTS

Fbxw7 messenger RNA expression level in the non-tumor tissues was significantly higher than that in the tumor tissues. In the analysis of Fbxw7 expression in tumor and non-tumor tissues, disease-free survival rate in the Fbxw7 high expression group was significantly higher than that in the low expression group. In multivariable analysis, Fbxw7 low expression in both tumor and non-tumor tissue was detected as the strongest independent risk factor for HCC recurrence.

CONCLUSIONS

Low Fbxw7 expression in both tumor and non-tumor tissue may be an independent prognostic factor for tumor recurrence after hepatectomy in patients with HCC.

Specific miRNA expression profiles of non-tumor liver tissue predict a risk for recurrence of hepatocellular carcinoma

AIM

It is reasonable to investigate non-tumor liver tissues to predict a risk for development of hepatocellular carcinoma (HCC). A molecular analysis of chronically damaged liver tissues may identify specific miRNA expression profiles associated with a risk for multicentric (MC) HCC.

METHODS

Twenty HCC patients, who underwent a curative hepatectomy were classified into two groups: a non-MC group (no MC recurrence in more than 3 years, n = 10) and an MC group (MC recurrence within 3 years after hepatectomy, n = 10). An miRNA microarray (955 probes) was used to compare the miRNA expression patterns of the non-cancerous liver tissues between the two groups. This study identified the differentially expressed miRNA related to MC recurrence in the liver remnant.

RESULTS

No differences were observed between the two groups in the liver function tests and pathological variables including both tumor factors and non-tumor liver tissues. The investigation selected 20 differentially expressed miRNA related to MC recurrence. Eighteen miRNA were downregulated, while two miRNA were upregulated in the MC group. A hierarchical clustering analysis identified a cluster that may be associated with risk of the MC recurrence of HCC. The MC recurrence-related miRNA included let-7d*, miR-328 and miR18a*, which potentially regulate K-ras gene expression. A significant inverse correlation between the miR-18a* expression and the K-ras mRNA expression was confirmed by quantitative reverse transcription polymerase chain reaction.

CONCLUSION

Specific miRNA expression signatures in non-cancerous liver tissue may help to predict the risk for de novo development of HCC.

Treatment With Dimethyl Fumarate Attenuates Calcineurin Inhibitor-induced Nephrotoxicity

BACKGROUND

Cyclosporine A (CsA) is an immunosuppressive drug which has been widely used to prevent rejection after organ transplantation. However, its therapeutic use is limited by nephrotoxicity, in part mediated by oxidative stress. The present study aims to investigate the protective effects of dimethyl fumarate (DMF) on CsA-induced nephrotoxicity by enhancing the antioxidant defense system.

METHODS

Male Sprague-Dawley rats were treated with CsA (n = 8, 20 mg/kg per day intraperitoneally) or CsA + DMF (n = 7, 50 mg/kg per day orally) for 28 days. Renal function, histopathology, malondialdehyde (MDA), myeloperoxidase levels, and antioxidant enzyme expression were determined.

RESULTS

The DMF cotreatment ameliorated CsA-induced renal dysfunction as evidenced by significant decrease in serum creatinine (CsA 0.79 ± 0.02 mg/dL vs CsA + DMF 0.62 ± 0.04 mg/dL, P = 0.001) and urea (CsA 66.9 ± 0.4 mg/dL vs CsA + DMF 53.3 ± 2.6 mg/dl, P < 0.0001) levels, as well as improvement of creatinine clearance. Dimethyl fumarate also significantly decreased serum MDA and renal tissue MDA and myeloperoxidase contents. The protein expression of NAD(P)H quinone oxidoreductase-1, a major cellular antioxidant and detoxifying enzyme, was significantly enhanced by DMF administration in kidney.

CONCLUSIONS

Administration of DMF has a protective potential against CsA nephrotoxicity. The protection afforded by DMF is mediated in part through inhibiting oxidative stress and inflammation and enhancing the antioxidant capacity.

The Impact of Indoleamine 2,3-dioxygenase (IDO) Expression on Stage III Gastric Cancer

BACKGROUND/AIM

Indoleamine 2,3-dioxygenase (IDO) down-regulates T cell activation, attenuates regulatory T cell (Treg) activation and is related to immune tolerance. The aim of the study was to clarify the significance of IDO expression and analyze the relationships between the expression of IDO, TGF-β, and Foxp3 in gastric cancer (GC).

PATIENTS AND METHODS

A total of 60 patients who underwent curative gastrectomy for stage III gastric cancer were included in the study. The expression of IDO, TGF-β, and Foxp3 was examined by immunohistochemistry and the relationship of each expression level to several prognostic factors was examined using univariate and multivariate analyses.

RESULTS

IDO expression was not positively correlated with any of the factors examined. IDO expression was positively correlated with TGF-β expression (p<0.05), and TGF-β expression was positively correlated with FoxP3 expression (p<0.05). Overall survival (OS) rates were significantly poorer in the IDO-positive group compared to the IDO-negative group (3-year OS, 78.5% vs. 90%, respectively; p<0.05). Multivariate analysis confirmed IDO expression as independent prognostic factors in OS. Disease-free survival (DFS) was significantly poorer in the IDO-positive group compared to the IDO-negative group (3-year DFS, 59.3% vs. 69.3%, respectively; p<0.05).

CONCLUSION

IDO is associated with poor prognosis and immuno-tolerance through attenuation of Treg activation in Stage III GC.

Prediction of response to preoperative chemoradiotherapy and establishment of individualized therapy in advanced rectal cancer

Preoperative chemoradiotherapy (CRT) has become the standard treatment for patients with locally advanced rectal cancer. However, no specific biomarker has been identified to predict a response to preoperative CRT. The aim of the present study was to assess the gene expression patterns of patients with advanced rectal cancer to predict their responses to preoperative CRT. Fifty-nine rectal cancer patients were subjected to preoperative CRT. Patients were randomly assigned to receive CRT with tegafur/gimeracil/oteracil (S-1 group, n=30) or tegafur-uracil (UFT group, n=29). Gene expression changes were studied with cDNA and miRNA microarray. The association between gene expression and response to CRT was evaluated. cDNA microarray showed that 184 genes were significantly differentially expressed between the responders and the non‑responders in the S-1 group. Comparatively, 193 genes were significantly differentially expressed in the responders in the UFT group. TBX18 upregulation was common to both groups whereas BTNL8, LOC375010, ADH1B, HRASLS2, LOC284232, GCNT3 and ALDH1A2 were significantly differentially lower in both groups when compared with the non-responders. Using miRNA microarray, we found that 7 and 16 genes were significantly differentially expressed between the responders and non-responders in the S-1 and UFT groups, respectively. miR-223 was significantly higher in the responders in the S-1 group and tended to be higher in the responders in the UFT group. The present study identified several genes likely to be useful for establishing individualized therapies for patients with rectal cancer.

The Significance of MicroRNA-449a and Its Potential Target HDAC1 in Patients With Colorectal Cancer

BACKGROUND

In a previous study, we demonstrated that deficiency of microRNA-449a (miR-449a) promoted colorectal tumorigenesis. In this study, the significance of miR-449a in the prognosis and relationship with HDAC1 in colorectal cancer was examined.

MATERIALS AND METHODS

Seventy-two patients with colorectal cancer and 16 patients with colorectal liver metastasis who underwent surgery were included. miR-449a expression in tumor tissue of resected specimen was investigated by real-time polymerase chain reaction and histone deacetylase 1 (HDAC1) expression was examined by immunohistochemistry.

RESULTS

Lymphovascular invasion and increased serum carcinoembryonic antigen levels were seen more frequent in patients with low miR-449a expression. Patients with low miR-449a expression were found to have a poorer prognosis than those with high expression. Vascular invasion, increased serum carbohydrate antigen 19-9 level and low miR-449a were associated with poorer disease-free survival. miR-449a expression was lower in metastatic liver tumor compared to primary tumor. HDAC1 positivity was higher in patients with low miR-449a.

CONCLUSION

miR-449a level might be a prognostic indicator for colorectal cancer and miR-449a might regulate HDAC1 expression.

The safety and usefulness of the single incision, transabdominal pre-peritoneal (TAPP) laparoscopic technique for inguinal hernia

BACKGROUND

The safety and usefulness of the SILS-TAPP (transabdominal pre-peritoneal) procedure remain unclear. The aim of this study was to clarify the safety and usefulness of the SILS-TAPP procedure compared with standard laparoscopic TAPP and TEPP (totally extra-peritoneal pre-peritoneal) procedures.

PATIENTS AND METHODS

85 patients underwent laparoscopic inguinal hernia repairs (TEPP, 30 patients; TAPP, 20 patients; SILS-TAPP, 35 patients) from 2007 to 2011. The operative outcomes of the three groups were compared.

RESULTS

There was no difference in the patients' characteristics among the three groups. The TEPP Group had a longer operation time. One patient in the SILS-TAPP group had an intraoperative complication. One patient in the TAPP group had a postoperative complication, and one patient had ileus and one had an umbilical hernia in the SILS-TAPP group. The postoperative hospital stay was not significantly different among the three groups. There were no recurrences in the TEPP group, 1 case of recurrence (5.0%) in the TAPP group, and 1 case (2.9%) in the SILS-TAPP group.

CONCLUSIONS

The present findings show that the SILS-TAPP repair is safe and feasible for the repair of adult inguinal hernia.