DcR3 and survivin are highly expressed in colorectal carcinoma and closely correlated to its clinicopathologic parameters

The Role of Decoy Receptor DcR3 in Gastrointestinal Malignancy

Malignancies are among the leading causes of mortality worldwide. Early detection and treatment are the primary targets of clinical and translational research, and may be facilitated by the recognition of novel diagnostic and prognostic biomarkers. Decoy receptor 3 (DcR3) is a soluble receptor of the tumor necrosis factor receptor superfamily of proteins (TNFRSF), which associates with its respective TNF-like ligands, Fas-L, LIGHT, and TL1A. DcR3 has been recognised as a significant anti-apoptotic factor with prominent involvement in various inflammatory and neoplastic conditions. Increased intratumor expression of DcR3 and elevated soluble DcR3 protein content in the sera of patients has been reported for various malignancies. Recent published work has suggested that monitoring of local and systemic DcR3 may provide an attractive biomarker, mainly for defining subgroups of patients with aggressive tumor behaviour and poor prognosis. The aim of the present review is to summarize and critically present existing evidence regarding the potential clinical importance of monitoring DcR3 expression in patients with malignancies of the gastrointestinal tract, as well as liver and pancreatic cancer. We also present a detailed description of the pathophysiological basis that may underlie the involvement of DcR3 in gastrointestinal carcinogenesis. Based on these data, we comment on the potential applicability of DcR3 monitoring in the diagnosis and, most importantly, the prognostic stratification of patients.

Integrative analysis of TNFRSF6B as a potential therapeutic target for pancreatic cancer

Background

Pancreatic cancer is one of the most lethal malignant tumors worldwide with poor outcomes. Previous studies have shown that tumor necrosis factor receptor superfamily member 6b (TNFRSF6B) plays an important role in cancer progression and immunosuppression. However, the mechanisms by which TNFRSF6B influence pancreatic cancer, and the regulatory networks involved remain to be further studied.

Methods

This study analyzed the mRNA information and clinical data of patients from The Cancer Genome Atlas (TCGA) and the ONCOMINE databases. The gene co-expression data regarding TNFRSF6B was obtained from the c-BioPortal and used to explore the functional network of TNFRSF6B in pancreatic cancer, as well as its function in tumor immunity. Short hairpin (sh) RNA knock-down experiments were performed to examine the functional roles of TNFRSF6B in pancreatic cancer cell lines.

Results

The expression of TNFRSF6B was elevated in pancreatic cancer tissues compared to normal pancreatic tissues, and its high expression was associated with poor prognosis of patients with pancreatic cancer. TNFRSF6B was found to be widely involved in cell cycle processes, apoptosis, apoptosis signaling pathways, immune responses, and responses to interferon. Knock-down of TNFRSF6B expression inhibited pancreatic cancer cell proliferation and invasion in vitro. Moreover, carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) was found to be co-expressed with TNFRSF6B, and there was a positive correlation between these molecules in pancreatic cancer cells.

Conclusions

This report suggested that TNFRSF6B has a critical role in the progression and metastasis of pancreatic cancer. These findings provide novel insights into the role of TNFRSF6B in the functional network of pancreatic cancer, and suggest that TNFRSF6B may be a potential therapeutic target.

DcR3 promotes proliferation and invasion of pancreatic cancer via a DcR3/STAT1/IRF1 feedback loop

Pancreatic cancer (PC) is one of the most common gastrointestinal malignancies that are highly aggressive with a low 5-year survival rate. Accumulated evidence has indicated that decoy receptor 3 (DcR3) is involved in several pathologic processes and various cancers. However, the mechanisms underlying dysregulated DcR3 expression and activation in PC remain to be fully established. In this study, we investigate the function and regulatory network of DcR3 in PC. We found that DcR3 was upregulated in PC tissues and serum. High DcR3 expression was associated with aggressive clinicopathological features and poor prognosis. Functionally, DcR3 not only increased cell migration and invasion in vitro but also promoted tumour growth both in vitro and in vivo by loss-of-function and gain-of-function experiments. Mechanistically, DcR3 promoted the phosphorylation of signal transducers and activators of transcription 1 (STAT1), leading to a dramatic increase in interferon regulatory factor 1 (IRF1). IRF1 then increased the transcriptional activity of DcR3, forming a positive feedback loop to reinforce DcR3 expression. In addition, DcR3 promoted carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) expression through activated IRF1. In conclusion, our findings provided novel insights into the function and mechanism of DcR3 in the pathogenesis of PC, which may be a potential therapeutic target for PC.

Decoy Receptor 3 Expression Is Associated With Wild-Type EGFR Status, Poor Differentiation of Tumor, and Unfavorable Patient Outcome

OBJECTIVES

The role of decoy receptor 3 (DcR3) in lung cancer, particularly adenocarcinoma, has not been well studied. In this study, we aim to investigate the expression profile and the clinicopathologic implications of DcR3 expression in lung adenocarcinoma.

METHODS

Immunohistochemistry was used to examine DcR3 expression in 461 lung adenocarcinomas. The differences in DcR3 expression among the various histopathologic patterns were analyzed. The relationship between DcR3 expression and clinicopathologic parameters, including epidermal growth factor receptor (EGFR) mutation, was also investigated.

RESULTS

DcR3 expression was more frequently expressed in solid, micropapillary, and acinar patterns (P < .0001) and in tumors with wild-type EGFR status (P = .018). In addition, DcR3 expression portends a less favorable disease-free survival in stage I patients (P = .012).

CONCLUSIONS

The expression of DcR3 might be involved in the differentiation and progression of lung adenocarcinoma. Therefore, DcR3 may be applied clinically for prediction of tumor progression in stage I lung adenocarcinoma.

Immunophenotypic Comparison of Neoplasms of the Appendix, Right Colon, and Left Colon in Search of a Site-Specific Phenotypic Signature

Aims. The proximal colon derives from the midgut endoderm, the distal one third derives from the hindgut endoderm, and the distal anal canal is of ectodermal origin. At least 5 molecular subtypes of colorectal carcinomas (CRC) have been identified, and some have a marked preferential right-sided location. Histologically, some CRC are much more common in the appendix. We hypothesized that these findings suggest the existence of diverse molecular genetic colonic subregions and compared the expression of classic and recently discovered colorectal markers in tumors at various locations to determine if a site-specific immunophenotypic signature could be identified. Methods and Results. Immunostains for CK7, CK20, MUC2, MUC5AC, MUC6, SATB2, DCR3/TNF6B, CDX2, Ki-67, and MMR proteins were performed on 17 appendiceal low-grade mucinous neoplasms and 6 crypt cell adenocarcinomas of the appendix, 15 right-sided and 15 left-sided mucinous adenocarcinomas, 17 right-sided and 15 left-sided conventional adenocarcinomas, and 5 signet ring cell adenocarcinomas (SRCCA). Statistically significant differences in the expression of MUC2, MUC5AC, MUC6, CK7, and SATB2 by site and/or histologic type were documented. MMR deficiency showed a significant correlation with MUC5AC and MUC6 expression. DCR3, CDX2, and CK20 expression was consistent throughout the colon. A CK7+/CK20+ phenotype was most common in appendiceal tumors and SRCCA. Conclusions. Statistically significant differences in the expression of some markers by histologic type and site were documented, supporting the existence of regional molecular genetic heterogeneity in the colon that result in site-specific epigenetic susceptibilities, tumor phenotypes, and immunophenotypes.

DcR3 induces proliferation, migration, invasion, and EMT in gastric cancer cells via the PI3K/AKT/GSK-3β/β-catenin signaling pathway

Background

Decoy receptor 3 (DcR3) has been reported to be overexpressed in a wide variety of malignancies and is correlated with tumorigenesis and progression. In gastric cancer (GC), DcR3 overexpression is associated with lymph node and distant metastasis, as well as poor prognosis. However, the functional role of DcR3 expression in GC remains elusive.

Purpose

The aim of this study is to elucidate the direct role of DcR3 in regulating GC progression and metastasis and identify the potential mechanism.

Methods

DcR3 expression was stably knocked down in HGC27 and MKN28 cells by transfecting the cells with DcR3 shRNA using lentiviral vector system. After the knockdown of DcR3 was confirmed, cell proliferation, colony formation, cell cycle distribution, apoptosis, cell invasion and migration were assessed in vitro. In addition, Western blot analysis was performed to evaluate the expression of downstream mediators of DcR3. Comparisons between multiple groups were performed using one-way analysis of variance (ANOVA) or unpaired Student’s t-test. Differences were considered significant at P<0.05.

Results

Our findings demonstrate that DcR3 induces proliferation, migration, invasion, and promotes epithelial-mesenchymal transition (EMT) of GC cells. In addition, DcR3 increases the expression levels of several components of the PI3K/AKT/GSK-3β/β-catenin signaling pathway, such as p-AKT, GSK-3β, p-GSK-3β and β-catenin. Additionally, DcR3 also enhances the expression of N-cadherin and Vimentin and decreases the expression of E-cadherin.

Conclusion

In summary, the findings of this study indicate that during GC progression, DcR3 plays a key role in cell proliferation and invasion via the PI3K/AKT/GSK-3β/β-catenin signaling pathway. Thus, targeting DcR3 might be a potential therapeutic approach for the treatment of GC.

Effects of Sepantronium Bromide (YM-155) on the Whole Transcriptome of MDA-MB-231 Cells: Highlight on Impaired ATR/ATM Fanconi Anemia DNA Damage Response

Sepantronium bromide (YM-155) is believed to elicit apoptosis and mitotic arrest in tumor cells by reducing (BIRC5, survivin) mRNA. In this study, we monitored changes in survivin mRNA and protein after treating MDA-MB-231 cells with YM-155 concurrent with evaluation of whole transcriptomic (WT) mRNA and long intergenic non-coding RNA at 2 time points: 8 h sub-lethal (83 ng/mL) and 20 h at the LC50 (14.6 ng/mL). The data show a tight association between cell death and the precipitating loss of survivin protein and mRNA (-2.67 fold-change (FC), p<0.001) at 20 h, questioning if the decline in survivin is attributed to cell death or drug impact. The meager loss of survivin mRNA was overshadowed by enormous differential change to the WT in both magnitude and significance for over 2000 differentially up/down-regulated transcripts: (+22 FC to -12 FC, p<0.001). The data show YM-155 to up-regulate transcripts in control of circadian rhythm (NOCT, PER, BHLHe40, NFIL3), tumor suppression (SIK1, FOSB), histone methylation (KDM6B) and negative feedback of NF-kappa B signaling (TNFAIP3). Down-regulated transcripts by YM-155 include glucuronidase (GUSBP3), numerous micro-RNAs, DNA damage repair elements (CENPI, POLQ, RAD54B) and the most affected system was the ataxia-telangiectasia mutated (ATM)/Fanconi anemia E3 monoubiquitin ligase core complexes (FANC transcripts - A/B/E/F/G/M), FANC2, FANCI, BRCA1, BRCA2, RAD51, PALB2 gene and ATR (ATM- and Rad3-Related) pathway. In conclusion, these findings suggest that a primary target of YM-155 is the loss of replicative DNA repair systems.

Prognostic value of DcR3 in solid tumors: A meta-analysis

BACKGROUND

Decoy receptor 3 (DcR3) has been reported to be overexpressed in a wide range of solid tumors, suggesting that DcR3 plays a crucial role in the development and progression of cancer. The present meta-analysis assesses the association between DcR3 expression and prognosis in patients with solid tumors.

METHODS

Eligible studies were identified by searching the PubMed, Web of Science, Cochrane Library, EMBASE, Chinese CNKI, and Wan Fang databases. The pooled hazard ratios (HRs) for overall survival (OS) and recurrence-free survival (RFS) were calculated using fixed effects models and random effects models, respectively.

RESULTS

Data from the 16 included studies, with 2209 patients, were reviewed and analyzed. DcR3 overexpression was significantly associated with worse OS in patients with solid tumors, but its expression might not be related to RFS in malignancies.

CONCLUSIONS

Current evidence demonstrates that increased DcR3 expression correlates with a poor prognosis in cancer patients, which suggests that the expression status of DcR3 is a useful biomarker for the prediction of prognosis in patients with solid tumors.

Downregulation of DcR3 sensitizes hepatocellular carcinoma cells to TRAIL-induced apoptosis

Decoy receptor 3 (DcR3) has been recently described as an antiapoptosis and prometastasis factor since it can competitively bind to FasL, TL1A, and LIGHT, and it is highly expressed in many malignant tumors. Downregulation of DcR3 can promote tumor cell apoptosis and inhibit metastasis. A previous study demonstrated that reduction of DcR3 could induce tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in pancreatic cancer cells. However, whether such an effect is seen in hepatocellular carcinoma (HCC) remains to be explored. This study was designed to investigate the sensitivity of HCC cells to TRAIL after silencing DcR3, and this was done by evaluating the expression of DcR3 in HCC cells and the effect on TRAIL-mediated apoptosis after downregulation of DcR3. Our data showed that DcR3 was highly expressed in HepG2, BEL-7402, Hep3B, Huh-7, MHCC97H, and SMCC7721 cell lines compared with normal liver cell line LO-2. Both HepG2 and BEL-7402 were tolerant to TRAIL-mediated apoptosis, and the tolerance was negatively correlated to the expression of DcR3. Silencing of DcR3 with shRNA and treatment with TRAIL induced obvious apoptosis in HepG2 and BEL-7402, with more cancer cells found in the G1 phase. SiDcR3 combined with TRAIL could induce activation of caspases-3, -8, and -9, raise the expression of the apoptotic protein Bax, and reduce the expression of antiapoptotic proteins (Bcl-2, Mcl-1, Bcl-XL, IAP-2, and survivin). Caspase-8 inhibitor Ac-IETD-CHO significantly decreased the activation of caspase cascade, indicating that the extrinsic pathway may have a vital role in the apoptotic events induced by SiDcR3/TRAIL. Furthermore, our results showed that the TRAIL death receptor 5 (DR5) was upregulated and that DR5 neutralizing antibody abrogated the effect of SiDcR3. Our results demonstrated that downregulation of DcR3 could enhance TRAIL-mediated apoptosis in HCC through the death receptor pathway. In the future, this might be useful as a clinical treatment method of liver cancer.

Absolute quantification of DcR3 and GDF15 from human serum by LC-ESI MS

Biomarkers are widely used in clinical diagnosis, prognosis and therapy monitoring. Here, we developed a protocol for the efficient and selective enrichment of small and low concentrated biomarkers from human serum, involving a 95% effective depletion of high-abundant serum proteins by partial denaturation and enrichment of low-abundant biomarkers by size exclusion chromatography. The recovery of low-abundance biomarkers was above 97%. Using this protocol, we quantified the tumour markers DcR3 and growth/differentiation factor (GDF)15 from 100 μl human serum by isotope dilution mass spectrometry, using ¹⁵N metabolically labelled and concatamerized fingerprint peptides for the both proteins. Analysis of three different fingerprint peptides for each protein by liquid chromatography electrospray ionization mass spectrometry resulted in comparable concentrations in three healthy human serum samples (DcR3: 27.23 ± 2.49 fmol/ml; GDF15: 98.11 ± 0.49 fmol/ml). In contrast, serum levels were significantly elevated in tumour patients for DcR3 (116.94 ± 57.37 fmol/ml) and GDF15 (164.44 ± 79.31 fmol/ml). Obtained data were in good agreement with ELISA and qPCR measurements, as well as with literature data. In summary, our protocol allows the reliable quantification of biomarkers, shows a higher resolution at low biomarker concentrations than antibody-based strategies, and offers the possibility of multiplexing. Our proof-of-principle studies in patient sera encourage the future analysis of the prognostic value of DcR3 and GDF15 for colon cancer patients in larger patient cohorts.

Prognostic and clinicopathological differences of DcR3 in gastrointestinal cancer: evidence from meta-analysis

Many studies reported that DcR3 participated in the clinicopathological characteristics of gastrointestinal cancer, however, they all included few patients and had inconsistent results. So we conducted a meta-analysis to explore the correlation between overexpression of DcR3 and the clinicopathological characteristics of gastrointestinal cancer. Identical search strategies were used to search relevant literatures in PubMed, Web of Science and Chinese Biomedical Literature Database. The prognostic significances and clinicopathological differences of DcR3 in gastrointestinal cancer were analyzed. A total of 28 studies comprising 3294 gastrointestinal cancer patients met the inclusion criteria. Overexpression of DcR3 was closely related with these clinicopathological features, including TNM stages (OR = 1.63, 95% CI 1.35-1.98), grade of differentiation (OR = 1.31, 95% CI 1.10-1.56), lymph node metastasis (OR = 2.02, 95% CI 1.66-2.47), infiltration degree (OR = 1.72, 95% CI 1.38-2.12), and metastasis (OR = 1.66, 95% CI 1.27-2.16). DcR3 may play an important role in gastrointestinal cancer, and DcR3 indicated distinct clinicopathologic features.

Experimental study on Qizhu formula for modulating survivin, an inhibitor of apoptosis, in MGC-803 gastric cancer cells

The aim of this study was to investigate the mechanism of action of Qizhu formula, a Chinese medicinal empirical formula, in modulating the action of survivin, an inhibitor of apoptosis, in MGC-803 gastric cancer cells. Western blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) were applied to detect the effect of varying concentrations of Qizhu formula in the modulation of the expression of survivin in MGC-803 human gastric adenocarcinoma cells. The western blot analysis results demonstrated that Qizhu formula exerted no significant effects on the protein expression of the β-actin housekeeping gene, whereas it exerted a significant inhibitory effect on the protein expression of the apoptosis-related survivin gene at concentrations of 250 μg/ml and, particularly, 500 μg/ml. RT-PCR was used to detect the effect of Qizhu formula on survivin mRNA in MGC-803 human gastric adenocarcinoma cells. The ratio of survivin/β-actin in the 0.1% dimethylsulfoxide and the 125, 250 and 500 μg/ml groups of Qizhu formula was 0.4543, 0.4025, 0.2415 and 0.2235, respectively. Therefore, Qizhu formula exerted a distinct inhibitory effect on the mRNA expression of survivin in MGC-803 cells in a dose-dependent manner. In conclusion, Qizhu formula may modulate the apoptosis of MGC-803 human gastric adenocarcinoma cells, which is associated with the downregulation of survivin mRNA and protein expression.

Copy number alterations in small intestinal neuroendocrine tumors determined by array comparative genomic hybridization

Background

Small intestinal neuroendocrine tumors (SI-NETs) are typically slow-growing tumors that have metastasized already at the time of diagnosis. The purpose of the present study was to further refine and define regions of recurrent copy number (CN) alterations (CNA) in SI-NETs.

Methods

Genome-wide CNAs was determined by applying array CGH (a-CGH) on SI-NETs including 18 primary tumors and 12 metastases. Quantitative PCR analysis (qPCR) was used to confirm CNAs detected by a-CGH as well as to detect CNAs in an extended panel of SI-NETs. Unsupervised hierarchical clustering was used to detect tumor groups with similar patterns of chromosomal alterations based on recurrent regions of CN loss or gain. The log rank test was used to calculate overall survival. Mann–Whitney U test or Fisher’s exact test were used to evaluate associations between tumor groups and recurrent CNAs or clinical parameters.

Results

The most frequent abnormality was loss of chromosome 18 observed in 70% of the cases. CN losses were also frequently found of chromosomes 11 (23%), 16 (20%), and 9 (20%), with regions of recurrent CN loss identified in 11q23.1-qter, 16q12.2-qter, 9pter-p13.2 and 9p13.1-11.2. Gains were most frequently detected in chromosomes 14 (43%), 20 (37%), 4 (27%), and 5 (23%) with recurrent regions of CN gain located to 14q11.2, 14q32.2-32.31, 20pter-p11.21, 20q11.1-11.21, 20q12-qter, 4 and 5. qPCR analysis confirmed most CNAs detected by a-CGH as well as revealed CNAs in an extended panel of SI-NETs. Unsupervised hierarchical clustering of recurrent regions of CNAs revealed two separate tumor groups and 5 chromosomal clusters. Loss of chromosomes 18, 16 and 11 and again of chromosome 20 were found in both tumor groups. Tumor group II was enriched for alterations in chromosome cluster-d, including gain of chromosomes 4, 5, 7, 14 and gain of 20 in chromosome cluster-b. Gain in 20pter-p11.21 was associated with short survival. Statistically significant differences were observed between primary tumors and metastases for loss of 16q and gain of 7.

Conclusion

Our results revealed recurrent CNAs in several candidate regions with a potential role in SI-NET development. Distinct genetic alterations and pathways are involved in tumorigenesis of SI-NETs.

Silencing of decoy receptor 3 (DcR3) expression by siRNA in pancreatic carcinoma cells induces Fas ligand-mediated apoptosis in vitro and in vivo

Decoy receptor 3 (DcR3) is abundantly expressed in human tumors and protects cells from a wide range of apoptotic stimuli. In this study, we demonstrate that DcR3 is overexpressed in pancreatic carcinoma cells, and that the pancreatic carcinoma cell lines, Panc-1 and SW1990, are resistant to Fas ligand (FasL)-mediated apoptosis. To further define the function of DcR3 in cell growth and apoptosis, we used small interfering RNA (siRNA) to knockdown the expression of the DcR3 gene in Panc-1 and SW1990 cells. Our results revealed that the silencing of DcR3 expression enhanced the inhibitory effects of FasL and reduced the capabiltiy of the cells for proliferation and colony formation in vitro. In addition, the downregulation of DcR3 modulated the cell apoptotic regulators, Fas-associated death domain (FADD), caspase‑3 and caspase‑8, thus triggering cell apoptosis. Furthermore, the knockdown of DcR3 inhibited the growth of Panc-1 tumor xenografts. Taken together, our findings indicate that DcR3 is important in cancer progression and may be a used as a potential therapeutic target for the gene therapy of pancreatic carcinoma.

Prognostic and clinicopathological significance of survivin in colorectal cancer: a meta-analysis

Survivin/BIRC5 is a potentially interesting prognostic marker and therapeutic target in colorectal cancer (CRC). However, the available data on survivin expression in CRC are heterogeneous. Thus, to clarify the prognostic relevance of survivin in patients with CRC and its association with clinicopathological parameters we performed a meta-analysis. We screened PubMed and EMBASE for those studies that investigated the prognostic value of survivin and its association with clinicopathological parameters in CRC. Data from eligible studies were extracted and included into the meta-analyses using a random effects model. Electronical literature search identified 15 studies including 1934 patients with CRC mostly detecting survivin by immunohistochemistry (IHC). Pooled hazard ratios of 11 studies that performed survival analysis revealed a positive correlation between survivin expression and poor prognosis (HR 1.93; 95% CI: 1.55–2.42; P<0.00001; I² = 23%). Subgroup analyses with respect to the detection method, HR estimation, global quality score and the country of origin in which the study was conducted supported the stability of this observation. In addition, meta-analyses revealed a significant association between expression of survivin and the presence of lymph node metastases (OR: 0.37; 95% CI: 0.19–0.75; I² = 61%) or blood vessel invasion (OR: 0.50; 95% CI: 0.28–0.90; I² = 0%). Expression of survivin indicates poor prognosis and a pro-metastatic phenotype and may be useful in identifying a subgroup of patients that could benefit from a targeted therapy against survivin in CRC.

Assessing DcR3 expression in relation to survivin and other prognostic factors in B cell non-Hodgkin's lymphoma

The soluble decoy receptor 3 (DcR3) is a member of the tumor necrosis factor receptor superfamily whose overexpression has been observed in several human malignancies. Survivin is one of the inhibitors of apoptosis proteins that are thought to play an important role in the pathogenesis of malignancies. We aimed to evaluate the expression of DcR3 in relation to survivin in B cell non-Hodgkin`s lymphoma (NHL) and then we focused on patients with diffuse large B cell non-Hodgkin's lymphoma (DLBCL) (50 cases) and correlated DcR3 expression with survivin expression and other prognostic parameters. Fifteen subjects with reactive lymphoid hyperplasia were included as controls. The expression of DcR3 and survivin were analyzed by immunohistochemistry on formalin-fixed paraffin-embedded lymph node sections from 80 cases of B cell NHL and 15 controls. Bone marrow biopsy sections of patients were also immunostained with the previous markers.

RESULTS

DcR3 expression was found in 32.5% of B cell NHL patients versus 6.7% of controls (p <0.001) and was associated with the aggressive/highly aggressive subtypes. DcR3 was strongly expressed in 30% of DLBCL patients, where it was associated with survivin expression, high international prognostic index (IPI), the presence of extra nodal disease, ECOG performance status >1, reduced remission rates and shorter event-free survival. The expression of survivin was 40% in B cell NHL patients versus 13.3% in the control group (p <0.001). The expression of survivin in aggressive/highly aggressive B cell NHL was significantly higher than that in indolent B cell NHL. Survivin expression has been detected in 44% of the DLBCL patients and was associated with their clinical stage and shorter event-free survival (p = 0.026). Bone marrow biopsy sections from DLBCL patients showed significant DcR3 and survivin over expressions in sections with infiltration by lymphoma cells than sections with no infiltration.

CONCLUSION

DcR3 expression was associated with other prognostic factors including survivin, reduced remission rates, and shorter event-free survival. Survivin is closely related to aggressive/highly aggressive subtypes of B cell NHL and is associated with shorter event-free survival. Both DcR3 and survivin expressions on bone marrow sections can be of help in diagnosing bone marrow infiltration.

Expression of AQP5 and AQP8 in human colorectal carcinoma and their clinical significance

Background

The aquaporins (AQPs) are a family of small membrane transport proteins whose overexpression has been implicated in tumorigenesis. However, the expression of AQP5 and AQP8 in colorectal cancer and the clinical significance remain unexplored. This study aimed to detect the expression of AQP5 and AQP8 in clinical samples of colorectal cancer and analyze the correlations of their expression with the clinicopathological features of colorectal cancer.

Methods

Forty pairs of colorectal cancer tissue and paraneoplastic normal tissue were obtained at the time of surgery from patients with colorectal cancer. The expression of AQP5 and AQP8 was detected by immunohistochemical staining and reverse transcriptase polymerase chain reaction.

Results

AQP5 was mainly expressed in colorectal carcinoma cells and barely expressed in paraneoplastic normal tissues. By contrast, AQP8 was mainly expressed in paraneoplastic normal tissues and barely expressed in colorectal carcinoma cells. AQP5 expression was not significantly associated with the sex or age of the patient with colorectal cancer (P>0.05), but was closely associated with the differentiation, tumor-nodes-metastasis stage and distant lymph node metastasis of colorectal carcinoma (P<0.05).

Conclusions

AQP5 might be a novel prognostic biomarker for patients with colorectal cancer.

Bufalin induces the apoptosis of acute promyelocytic leukemia cells via the downregulation of survivin expression

BACKGROUND AND AIMS

Bufalin is a cardiotonic steroid isolated from the Chinese toad venom preparation Chan'su and has been shown to induce leukemia cell differentiation and apoptosis under certain experimental conditions. However, the detailed mechanism by which bufalin induces the apoptosis of acute promyelocytic leukemia cells is largely unexplored.

METHODS

The acute promyelocytic leukemia cell line NB4 was treated with bufalin, then the proliferation was evaluated by cell viability assay and apoptosis was detected by flow cytometry analysis. In addition, NB4 cells were treated by MEK inhibitor PD98059 in combination with bufalin, and the expression of survivin and activation of caspase-3 were detected by Western blot analysis.

RESULTS

Bufalin inhibited the proliferation and induced the apoptosis of NB4 cells in a dose- and time-dependent manner. Moreover, bufalin synergized with PD98059 to inhibit the proliferation and induce the apoptosis of NB4 cells, which was associated with the downregulation of survivin expression and the upregulation of caspase-3 activation.

CONCLUSIONS

Bufalin is a potential regimen to be used in combination with conventional chemotherapeutic drugs to improve acute promyelocytic leukemia therapy.

The expression and clinical significance of PI3K, pAkt and VEGF in colon cancer

Background PI3K/Akt signaling has been shown to be activated in a variety of cancers. However, the correlation between Akt activation and VEGF expression is unclear in colon cancer tissues. This study aimed to investigate the expression and predictive value of phosphorylated Akt (pAkt) and VEGF in colon cancer tissues. The expression of PI3K, pAkt and VEGF was detected by immunohistochemical staining in 60 samples of colon cancer tissues and their corresponding adjacent normal colon tissues. In addition, the correlations between the expression levels of the 3 proteins and the clinicopathological parameters of the colon cancer cases were analyzed. The positive rates of PI3K, pAkt and VEGF expression were 71.7% (43/60), 68.3% (41/60) and 61.7% (37/60) in colon cancer, respectively, which were significantly higher than in adjacent normal colon tissues (P<0.001). Correlation analyses showed that PI3K expression was not significantly associated with the gender or age of the patients, tumor size or differentiation (P>0.05), but was closely associated with serous coat infiltration and lymphatic metastasis of colon cancer (P<0.05). Neither pAkt nor VEGF expression were significantly associated with the gender or age of the patients, or tumor differentiation (P>0.05), but were closely associated with tumor size, serous coat infiltration and lymphatic metastasis of colon cancer (P<0.05). In addition, the expression levels of Pl3K and pAkt were positively correlated with that of VEGF in colon cancer tissues (P<0.05). Our data show a positive correlation between PI3K/Akt activation and VEGF expression in colon cancer tissues and indicate that pAkt is an independent prognostic marker for colon cancer patients.

Triptolide triggers the apoptosis of pancreatic cancer cells via the downregulation of Decoy receptor 3 expression

PURPOSE

Triptolide (TPL) is a diterpenoid triepoxide that effectively induces apoptosis in a wide variety of cancer cells. However, the detailed mechanism by which TPL activates caspase cascade remains elusive. This study aimed to examine the antitumor effects of TPL against pancreatic cancer and investigate the underlying mechanism.

METHODS

Cell proliferation was evaluated by sulforhodamine B assay. The apoptosis was evaluated by caspase activity assay, Western blot and flow cytometry. DcR3 level was measured by ELISA. AsPC-1 xenografts were established to compare the in vivo antitumor effects of TPL and Gemcitabine.

RESULTS

TPL inhibited the proliferation and induced the apoptosis of pancreatic cancer cells in a dose- and time-dependent manner. TPL also inhibited DcR3 expression in a dose- and time-dependent manner. siRNA-mediated DcR3 knockdown sensitized pancreatic cancer cells to TPL-induced apoptosis. In vivo, DcR3 siRNA significantly enhanced TPL-induced apoptosis and tumor growth inhibition. Moreover, TPL showed less toxicity compared to Gemcitabine in mice model.

CONCLUSIONS

TPL induces the apoptosis of pancreatic cancer cells via the downregulation of DcR3 expression and has the potential as an effective agent against pancreatic cancer.

Prognostic value of serum soluble Fas in patients with locally advanced unresectable rectal cancer receiving concurrent chemoradiotherapy

OBJECTIVE

This study was designed to detect the changes of serum soluble Fas (sFas) levels in patients with locally advanced unresectable rectal cancer (LAURC), and to explore its prognostic value of response.

METHODS

Soluble samples were obtained from LAURC subjects, treated by concurrent chemoradiotherapy, before treatment and one month after treatment. Healthy donor serum samples were used as controls. sFas concentration was measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The sFas levels before treatment and one month after treatment were both significantly higher in LAURC subjects than in healthy controls [(8.79±1.39) and (7.74±1.32) vs. (5.53±1.13) ng/L, P<0.01]. The sFas levels before treatment and one month after treatment were significantly lower in the response group (complete and partial responses) than in the non-response group (stable and progressive diseases) [(8.50±1.25) vs. (10.17±1.26) ng/L, P<0.01 and (7.50±1.24) vs. (8.90±1.13) ng/L, P<0.01, respectively]. The one-year survival rate was 54.2% and 82.6% in those with sFas levels >8.79 ng/L and <8.79 ng/L before treatment (P<0.02), respectively, 50.0% and 87.0% in those with sFas levels >7.74 ng/L and <7.74 ng/L one month after treatment (P<0.01), respectively.

CONCLUSIONS

The sFas level is higher in LAURC subjects than in healthy controls. Concurrent chemoradiotherapy can reduce sFas levels in LAURC patients. The monitoring of sFas may provide prognostic information for LAURC patients.

Aberrant expression and function of death receptor-3 and death decoy receptor-3 in human cancer

Death receptor-3 (DR3) and death decoy receptor-3 (DcR3) are both members of the tumour necrosis factor receptor (TNFR) superfamily. The TNFR superfamily contains eight death domain-containing receptors, including TNFR1 (also called DR1), Fas (also called DR2), DR3, DR4, DR5, DR6, NGFR and EDAR. Upon the binding of these receptors with their corresponding ligands, the death domain recruits various proteins that mediate both the death and proliferation of cells. Receptor function is negatively regulated by decoy receptors (DcR1, DcR2, DcR3 and OPG). DR3/DcR3 are a pair of positive and negative players with which vascular endothelial growth inhibitor (VEGI) interacts. VEGI has been suggested to be a potential tumour suppressor. The inhibitory effects of VEGI on cancer are manifested in three main areas: a direct effect on cancer cells, an anti-angiogenic effect on endothelial cells, and the stimulation of dendritic cell maturation. A recent study indicated that DR3 may be a new receptor for E-selectin, which has been reported to be associated with cancer metastasis. DcR3 is a soluble receptor, highly expressed in various tumours, which lacks an apparent transmembrane segment, prevents cytokine response through ligand binding and neutralization, and is an inhibitor of apoptosis. DcR3 serves as a decoy receptor for FasL, LIGHT and VEGI. The cytokine LIGHT activates various anti-tumour functions and is expected to be a promising candidate for cancer therapy. Certain tumours may escape FasL-dependent immune-cytotoxic attack by expressing DcR3, which blocks FasL function. DR3/DcR3 play profound roles in regulating cell death and proliferation in cancer. The present review briefly discusses DR3/DcR3 and attempts to elucidate the role of these negative and positive players in cancer.

Using detection of survivin-expressing circulating tumor cells in peripheral blood to predict tumor recurrence following curative resection of gastric cancer

BACKGROUND AND OBJECTIVES

The present study was designed to investigate the clinicopathological role of survivin-expressing circulating tumor cells (CTCs) and to determine whether the presence of survivin-expressing CTCs is an independent predictor of tumor recurrence following curative resection of gastric cancer.

METHODS

This study included 98 patients who underwent potentially curative resection. Reverse transcription polymerase chain reaction enzyme linked immunosorbent assay (RT-PCR ELISA) was used to measure survivin mRNA in peripheral blood.

RESULTS

Of the 98 patients studied, 45 (45.9%) were positive for survivin mRNA. Survivin mRNA expression correlated with Lauren classification (P < 0.001), pathological tumor (pT) stage (P < 0.001), pathological tumor node metastasis (pTNM) stage (P = 0.009), and degree of differentiation (P = 0.001). The pTNM stage and the status of survivin mRNA were independent prognostic factors of disease-free survival (P = 0.007 and <0.001, respectively).

CONCLUSIONS

The detection of CTCs expressing survivin mRNA could be a good clinical biomarker used to predict the prognosis of patients with curatively resected gastric cancer.

Silibinin exerts sustained growth suppressive effect against human colon carcinoma SW480 xenograft by targeting multiple signaling molecules

PURPOSE

Earlier, we reported the strong preventive efficacy of silibinin against colorectal cancer (CRC), but its usefulness against established CRC or effect of its withdrawal on CRC growth remained unknown. Present study focused on these important issues by employing two different treatment protocols in advanced human CRC SW480 xenograft in nude mice.

METHODS

In the first treatment protocol, silibinin was fed for 28 days (200 mg/kg body weight, 5 days/week) to mice with growing SW480 xenograft; thereafter, tumor growth was monitored for additional 3 weeks without silibinin treatment. In the second protocol, silibinin treatment was started after 25 days of SW480 cells injection (established tumors), and tumor growth was studied 4 days, 8 days and 16 days after silibinin treatment.

RESULTS

In both treatment protocols, silibinin had strong and sustained inhibitory effect on xenograft growth. Detailed xenograft analyses showed that silibinin, in both treatment protocols, exerts anti-proliferative, pro-apoptotic and anti-angiogenic effects. Further, silibinin reduced the expression of β-catenin and phospho-GSK3β in xenograft tissues. Silibinin also targeted signaling molecules involved in CRC proliferation and survival (cyclin D1, c-Myc and survivin) as well as angiogenesis regulators (VEGF and iNOS).

CONCLUSIONS

Collectively, these findings substantiate silibinin's therapeutic efficacy against CRC, advocating its translational potential.

p21-activated kinase 5 inhibits camptothecin-induced apoptosis in colorectal carcinoma cells

p21-activated kinase 5 (PAK5) is a recently identified member of the group B PAK family. The PAK proteins are effectors of the small GTPase Cdc42 and Rac1 and are known to regulate cell motility and activate cell-survival signaling pathways. Especially, the mitochondrial localization of PAK5 is vital to its effects on apoptosis and cell survival. Previously, we demonstrated that PAK5 expression increased significantly during the malignant progression of colorectal carcinoma (CRC) and that PAK5 promoted CRC metastasis by regulating CRC cell adhesion and migration. In the present study, we aim to investigate the role of PAK5 in camptothecin-induced apoptosis and its potential mechanism of action. Our results showed that overexpression of PAK5 inhibited camptothecin-induced apoptosis by inhibiting the activity of caspase-8 in CRC cells. Accordingly, knockdown of PAK5 in LoVo cells resulted in increased apoptosis. Mechanistically, we found that PAK5 directly phosphorylated Bad on serine 112 and indirectly led to phosphorylation of serine 136 via the Akt pathway. In conclusion, our study revealed previously unappreciated inhibitory role of PAK5 in camptothecin-induced apoptosis, thus suggesting PAK5 as a novel therapeutic target in CRC.