Soluble Fas might serve as a diagnostic tool for gastric adenocarcinoma

Serum Soluble Fas Levels and Incidence of Liver Cancer in Nested Case-Control Study

BACKGROUND

Soluble Fas (sFas) plays various roles in carcinogenesis and tumor dissemination by preventing apoptosis via binding to Fas ligand. We analyzed associations of serum sFas levels with the incidence of liver cancer in a prospective case-control study nested in the Japan Collaborative Cohort Study.

METHODS

A baseline survey was conducted from 1988, with blood samples obtained from 39,242 subjects. Patients diagnosed with liver cancer were regarded as cases. Two or three controls were selected and matched for sex, age, and geographic area. Conditional logistic regression was used to estimate ORs for cancer incidence associated with sFas.

RESULTS

This study contained 86 cases and 249 controls. After controlling for alcohol intake, body mass index, smoking, and hepatitis viral infection, participants with high sFas showed elevated risk of cancer (Ptrend = 0.003) and the third tertile of sFas showed a higher risk compared with the first tertile [OR, 3.53; 95% confidence interval (CI), 1.28-9.69]. In hepatocellular carcinoma, high sFas was associated with elevated risk (Ptrend < 0.001). In men and the elderly, subjects in the highest tertiles showed higher cancer risk. Limiting subjects to those followed for 3 years, high sFas was related to liver cancer risk (Ptrend = 0.033) and the third tertile showed a higher risk compared with the first (OR, 2.94; 95% CI, 0.94-9.14).

CONCLUSIONS

High serum sFas may be related to future risk of liver cancer.

IMPACT

Our findings highlight this biomarker for further analysis in pooled investigations with different/larger prospective cohorts.

A first-in-class, first-in-human, phase I trial of CIGB-552, a synthetic peptide targeting COMMD1 to inhibit the oncogenic activity of NF-κB in patients with advanced solid tumors

CIGB-552 is a synthetic peptide that interacts with COMMD1 and upregulates its protein levels. The objectives of this phase I study were safety, pharmacokinetic profile, evaluation of the lymphocytes CD4+ and CD8+ and preliminary activity in patients with advanced tumors. A 3 + 3 dose-escalation design with seven dose levels was implemented. Patients were included until a grade 3 related adverse event occurred and the maximum tolerated dose was reached. The patients received subcutaneous administration of CIGB-552 three times per week for 2 weeks. Single-dose plasma pharmacokinetics was characterized at two dose levels, and tumor responses were classified by RECIST 1.1. Twenty-four patients received CIGB-552. Dose-limiting toxicity was associated with a transient grade 3 pruritic maculopapular rash at a dose of 7.0 mg. The maximum tolerated dose was defined as 4.7 mg. Ten patients were assessable for immunological status. Seven patients had significant changes in the ratio CD4/CD8 in response to CIGB-552 treatment; three patients did not modify the immunological status. Stable disease was observed in five patients, including two metastatic soft sarcomas. We conclude that CIGB-552 at dose 4.7 mg was well tolerated with no significant adverse events and appeared to provide some clinical benefits.

Circulating Plasma Gelsolin: A Predictor of Favorable Clinical Outcomes in Head and Neck Cancer and Sensitive Biomarker for Early Disease Diagnosis Combined with Soluble Fas Ligand

Head and neck cancer (HNC) accounts for more than 330,000 cancer deaths annually worldwide. Despite late diagnosis being a major factor contributing to HNC mortality, no satisfactory biomarkers exist for early disease detection. Cytoplasmic gelsolin (cGSN) was discovered to predict disease progression in HNC and other malignancies, and circulating plasma gelsolin (pGSN) levels are significantly correlated with infectious and inflammatory disease prognoses. Here, the plasma levels of five candidate biomarkers (circulating pGSN, squamous cell carcinoma antigen, cytokeratin 19 fragment, soluble Fas, and soluble Fas ligand (sFasL)) in 202 patients with HNC and 45 healthy controls were measured using enzyme-linked immunosorbent assay or Millipore cancer multiplex assay. The results demonstrated that circulating pGSN levels were significantly lower in patients with HNC than in healthy controls. Moreover, circulating pGSN outperformed other candidate biomarkers as an independent diagnostic biomarker of HNC in both sensitivity (82.7%) and specificity (95.6%). Receiver operating characteristic curves indicated that combined pGSN and sFasL levels further augmented this sensitivity (90.6%) for early disease detection. Moreover, higher pGSN levels predicted improved prognosis at both 5-year overall survival and progression-free survival. In conclusion, circulating pGSN could be an independent predictor of favorable clinical outcomes and a novel biomarker for the early HNC detection in combination with sFasL.

Polymorphisms of extrinsic death receptor apoptotic genes (FAS -670 G>A, FASL -844 T>C) in coronary artery disease

Apoptosis plays an important role in atherogenesis and rupture of vulnerable plaques in coronary artery disease. FAS and FAS ligand (FASL) induce apoptosis when FAS binds to FAS-L. However sFas blocks apoptosis by binding to FAS and FASL or sFasL. The present study is sought to examine the role of extrinsic apoptotic genes (FAS, FASL) polymorphism and serum levels of FAS, FASL in the pathogenesis and susceptibility to CAD in south Indian population. The study included 300 CAD patients and 300 healthy controls. Lipid profiles, sFas, sFasL were estimated by commercially available kits. FAS -670 G>A, FASL -844 T>C genotypes were analyzed by PCR-RFLP. Secondary structures of pre mRNA were analyzed by the Vienna RNA webserver and gene-gene and gene-environment interactions were determined by MDR analysis. Total cholesterol, triglyceride and LDL levels were significantly high in CAD patients compared to the controls. Molecular analysis revealed that the frequency of the AA genotype of FAS (54% vs 27%) and CC genotypes of FASL (10.3% vs 1.3%) were high in CAD patients compared to controls. Secondary structure analysis of FAS and FASL confirmed our molecular analysis. sFas levels were low while serum sFasL were high in CAD patients. MDR analysis revealed synergistic effects of gene polymorphisms and additive effects of epidemiological factors on risk of CAD. Polymorphisms of FAS (-670 G/A), FASL (-844 T/C) and their circulating levels play an important role in the pathology of CAD.

Apoptosis Markers in Breast Cancer Therapy

Cancer is a disease characterized by a very little apoptosis, ie, genetically programmed cell death. Aberrations in apoptotic pathways are central to tumorigenesis, tumor progression, and overall tumor growth and regression in response to chemotherapy. It is now increasingly accepted that chemotherapeutic drug efficacy is partially related to its ability to induce apoptosis. Apoptosis, therefore, represents not only a vital target in cancer therapy but also a unique biomarker opportunity that has thus far been largely unexploited. In response to therapy, tumor cells undergo apoptosis and release their cellular components in the circulation. As such, these materials may serve as biomarkers to assess response. Apoptosis markers in breast cancer include circulating soluble FasL, granzyme B, and cytochrome c that increase following chemotherapy. Unfortunately, there is a paucity of information in the literature with respect to this approach. As such, large-scale prospective studies are clearly needed to validate this approach and more fully elucidate clinical usefulness.

Correlation and Significance of Urinary Soluble Fas and Vascular Endothelial Growth Factor in Bladder Urothelial Cancer

AIM

To investigate the correlation and significance between the urine soluble Fas (sFas) and vascular endothelial growth factor (VEGF) expression in patients with urothelial bladder carcinoma (UC).

METHODS

The level of sFas was measured by enzyme-linked immunosorbent assay (ELISA) and the expression of VEGF protein in UC surgical specimens was screened by immunohistochemical method. These data were analyzed through SPSS 13.0 software.

RESULTS

The urinary sFas levels were significantly higher in the patients with UC than in those without cancer (168.0 ng/mL ± 84.6 versus 56.2 ng/mL ± 37.0; P < 0.05) and in the cases with a higher stage or grade than in those with a lower stage or grade (each P < 0.05). They had a positive relationship between the expression of VEGF protein and the pathological stage or grade in UC tissues (each P < 0.05). Spearman rank correlation test showed a significant correlation between sFas levels and VEGF expressions (R = 0.882, P < 0.05).

CONCLUSIONS

The effects of sFas and VEGF may play important roles together in the occurrence and progression of UC. Joint detection of urine sFas plus VEGF protein may provide valuable solutions to improve the diagnosis and treatment of UC.

Effects of gastrokine‑2 expression on gastric cancer cell apoptosis by activation of extrinsic apoptotic pathways

Gastrokine‑2 is a putative gastric cancer‑specific tumor suppressor gene, the loss of which is known to be involved in the development and progression of gastric cancer, and restoration of gastrokine‑2 expression inhibits growth of gastric cancer cells in vitro. However, the underlying mechanism of these effects requires elucidation. In the present study, expression patterns of gastrokine‑2 protein were examined in gastric cancer tissues and cell lines. Expression of gastrokine‑2 was restored in gastric cancer cells in order to assess its effect on cell viability, apoptosis and gene expression. A total of 76 gastric cancer tissues with corresponding normal mucosae samples, and two gastric cancer cell lines (SGC‑7901 and AGS) were subjected to western blot analysis of gastrokine‑2 expression. SGC‑7901 cells were transiently transfected with gastrokine‑2 cDNA and then treated with anti‑CD95 and/or anti‑Fas antibodies prior to analysis of cell viability, apoptosis and gene expression levels. Expression of gastrokine‑2 protein was reduced or absent in gastric cancer tissues and gastric cancer cell lines. Following restoration of gastrokine‑2 expression, the protein expression level of Fas was significantly increased, but no marked change was observed in the levels of bcl‑2 and Bax proteins. Expression of gastrokine‑2 protein reduced gastric cancer cell viability and induced apoptosis. Activity of caspase‑3 and caspase‑8 was increased, but caspase‑9 activity remained unchanged in the SGC‑7901 cells. Reduction or knockout of gastrokine‑2 protein expression may contribute to gastric cancer development or progression, as the current study demonstrated that restoration of gastrokine‑2 expression induces apoptosis of gastric cancer cells through the extrinsic apoptosis pathway.

Kisspeptin effect on endothelial monocyte activating polypeptide II (EMAP-II)-associated lymphocyte cell death and metastases in colorectal cancer patients

Kisspeptin is an antimetastatic agent in some cancers that has also been associated with lymphoid cell apoptosis, a phenomenon favoring metastases. Our aim was to determine the association of kisspeptin with lymphocyte apoptosis and the presence of metastases in colorectal cancer patients. Blood was drawn from 69 colon cancer patients and 20 healthy volunteers. Tissue specimens from healthy and pathological tissue were immunohistochemically analyzed for kisspeptin and endothelial monocyte activating polypeptide II (EMAP-II) expression. Blood EMAP-II and soluble Fas ligand (sFasL) levels were examined by an enzyme-linked immunosorbent assay method. The kisspeptin and EMAP-II expression and secretion levels in the DLD-1 and HT-29 colon cancer cell lines were examined by quantitative real-time polymerase chain reaction, Western analysis and enzyme-linked immunosorbent assay, whereas lymphocyte viability was assessed by flow cytometry. The effect of kisspeptin on the viability of colon cancer cells was examined by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. Exogenous, synthetic and naturally produced, kisspeptin induces through the G-protein-coupled receptor 54 (GPR54; also known as the kisspeptin receptor) the EMAP-II expression and secretion in colon cancer cell lines, inducing in vitro lymphocyte apoptosis, as verified by the use of an anti-EMAP-II antibody. These results were reversed with the use of kisspeptin inhibitors and by kisspeptin-silencing experiments. Tumor kisspeptin expression was associated with the tumor EMAP-II expression (p < 0.001). Elevated kisspeptin and EMAP-II expression in colon cancer tissues was associated with lack of metastases (p < 0.001) in colon cancer patients. These data indicate the antimetastatic effect of tumor-elevated kisspeptin in colon cancer patients that may be mediated by the effect of kisspeptin on EMAP-II expression in colon cancer tumors in patients with normal serum EMAP-II levels. These findings provide new insight into the role of kisspeptin in the context of metastases in colon cancer patients.

Improved production of recombinant human Fas ligand extracellular domain in Pichia pastoris: yield enhancement using disposable culture-bag and its application to site-specific chemical modifications

BACKGROUND

A useful heterologous production system is required to obtain sufficient amounts of recombinant therapeutic proteins, which are often necessary for chemical characterization and engineering studies on the development of molecules with improved properties. Human Fas ligand extracellular domain (hFasLECD) is an agonistic death ligand protein that has potential applications for medical purposes. Site-specific chemical modifications can provide a powerful means for the development of engineered proteins with beneficial functions. This study aimed to enhance the yield of hFasLECD using a Pichia pastoris secretory expression system suitable for efficient production on a small laboratory scale, and further to provide procedures for its site-specific chemical modification without impairing the biological functions based on the developed production system.

RESULTS

A convenient cultivation system using a disposable plastic bag provided a three-fold increase in purification yield of tag-free hFasLECD as compared with the conventional system using a baffled glass flask. The system was further applied to the production of a mutant, which contains an additional reactive cysteine residue in the N-terminal tag-sequence region. Site-specific conjugations and cross-linking without impairing biological functions were achieved by reaction of the mutant hFasLECD with single maleimide group containing compounds and a linear polyethylene glycol derivative containing two maleimide groups at either end, respectively. All purified tag-free and chemically modified hFasLECDs showed an evident receptor binding activity in co-immunoprecipitation experiments mediated by wild-type and N-glycosylation site deficient mutant human Fas receptor extracellular domain derivatives. An N-Ethylmaleimide conjugated hFasLECD derivative demonstrated a significant cytotoxic activity against human HT-29 colorectal cancer cells.

CONCLUSIONS

A new, efficient cultivation system for enhanced secretory production of hFasLECD using P. pastoris and an effective strategy for site-specific chemical modifications of hFasLECD were devised. The results obtained constitute the basis for biomedical applications including developments of novel therapeutic proteins and diagnostic tools targeted to related diseases and their biomarkers.

High Fas expression in gastric carcinoma cells as a factor correlating with the occurrence of metastases to regional lymph nodes

PURPOSE

The aim of this study was to evaluate the correlation of the expression of Fas and Fas-L proteins in gastric carcinoma cells on the occurrence of metastases to regional lymph nodes.

MATERIAL/METHODS

The study included 89 patients treated surgically for gastric carcinoma. The evaluated clinicomorphological parameters were verified based on both histopathological material collected at surgery and intraoperative image. Fas and Fas-L expression was evaluated immunohistochemically in the neoplastic tissue of the removed gastric tumors.

RESULTS

A statistically significant positive correlation between Fas expression in gastric carcinoma cells and the number of regional lymph nodes affected by metastases was observed (p<0.05). No such correlation was noticed with respect to Fas-L. A statistically significant correlation between the depth of neoplastic infiltration of the stomach wall (T feature) and the number of affected lymph nodes was observed (p<0.05). No statistically significant correlations in the other examined clinicomorphological features and the number of metastatic lymph nodes was observed.

CONCLUSION

A positive Fas expression correlates with more frequent occurrence of metastases to regional lymph nodes. Determination of this protein expression in cancer cells prior to surgery may be helpful for planning the surgical procedure, especially with respect to the extent of lymph node excision.

Genetic variants in fas signaling pathway genes and risk of gastric cancer

Populations in north central China are at high risk for gastric cancers (GC), and altered FAS-mediated cell signaling and/or apoptosis may contribute to this risk. We examined the association of 554 single nucleotide polymorphisms (SNPs) in 53 Fas signaling-related genes using a pathway-based approach in 1758 GC cases (1126 gastric cardia adenocarcinomas (GCA) and 632 gastric noncardia adenocarcinomas (GNCA)), and 2111 controls from a genome-wide association study (GWAS) of GC in ethnic Chinese. SNP associations with risk of overall GC, GCA and GNCA were evaluated using unconditional logistic regressions controlling for age, sex and study. Gene- and pathway-based associations were tested using the adaptive rank-truncated product (ARTP) method. Statistical significance was evaluated empirically by permutation. Significant pathway-based associations were observed for Fas signaling with risk of overall GC (p = 5.5E-04) and GCA (p = 6.3E-03), but not GNCA (p= 8.1E-02). Among examined genes in the Fas signaling pathway, MAP2K4, FAF1, MAPK8, CASP10, CASP8, CFLAR, MAP2K1, CAP8AP2, PAK2 and IKBKB were associated with risk of GC (nominal p < 0.05), and FAF1 and MAPK8 were significantly associated with risk of both GCA and GNCA (nominal p< 0.05). Our examination of genetic variation in the Fas signaling pathway is consistent with an association of altered Fas signaling and/or apoptosis with risk of GC. As one of the first attempts to investigate a pathway-level association, our results suggest that these genes and the Fas signaling pathway warrant further evaluation in relation to GC risk in other populations.

Is urinary soluble Fas an independent predictor of non-muscle-invasive bladder cancer? A prospective chart study

OBJECTIVES

To evaluate whether soluble Fas (sFas) in urine is an independent predictor of non-muscle-invasive bladder cancer (NMIBC).

METHODS

We performed a prospective chart review which included 128 subjects with NMIBC and 88 controls. The first morning voided urine sample (10-20 ml) was obtained from preoperative patients and controls. Expression levels of sFas in urine were analyzed using enzyme-linked immunosorbent assay. Clinical and pathological data, European Organisation for Research and Treatment of Cancer (EORTC) risk group category, follow-up data and urinary sFas values were gathered from each patient, and each prognostic outcome was evaluated.

RESULTS

sFas levels were significantly higher in the urine of patients with NMIBC than of those without NMIBC (p = 0.000). The level was significantly higher in cases with a higher stage or grade or high-risk and recurrent disease than in those with a lower stage or grade or low-risk and nonrecurrent disease (each p < 0.05). Kaplan-Meier estimates revealed a significant difference in time to recurrence based on sFas levels in the urine of the NMIBC patients (log-rank test; p = 0.000). On multivariate Cox regression analysis, EORTC risk group category (hazards ratio [HR] = 3.250, p = 0.000) and urinary sFas level (HR = 1.403, p = 0.015) were the independent predictors of NMIBC recurrence.

CONCLUSIONS

Our study indicated that urinary sFas assay results may help identify NMIBC patients at risk of tumor recurrence. These data can be used to design a future follow-up schedule and treatment strategy for NMIBC patients.

Deletion polymorphism at chromosome 3q26.1 and oral squamous cell carcinoma

Several recent studies have investigated DNA instability in malignancies including deletions and duplications of part of the chromosome using array-based comparative genomic hybridization (CGH) analysis. Using the same approach on oral squamous cell carcinoma (OSCC) tissue samples, we found a frequent deletion at chromosome 3q26.1 in OSCC patients; this polymorphism showed a gene frequency of 0.293-0.368 in healthy volunteers (n=60) and 0.129-0.195 in OSCC patients (n=54). Detailed analysis around the polymorphic region revealed the deletion breakage point. A significant association of gene frequency for the deletion polymorphism between healthy volunteers and patients implicated genetic factors related to this polymorphism in the development of OSCC. Currently, no gene is predicted to lie within the 3,606-kbp region around the polymorphism. Thus, although a single-gene model could not explain the occurrence of OSCC, we believe that examining this polymorphism could be useful in identifying risk factors for OSCC.

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.

Immune clearance gastric carcinoma cells in ascites by activating caspase-9-induced apoptosis

Floating gastric adenocarcinoma cells in ascitic fluid are the main cause of peritoneal dissemination. Activation of apoptosis is an important mechanism by which tumor cells are eliminated by the immune surveillance system. Hence, we examined caspase-9 expression and the apoptosis in gastric adenocarcinoma cells in ascitic fluid using immunohistochemistry, real-time polymerase chain reaction and in situ cell death detection kits, flow cytometry. The results revealed strong expression of caspase-9 in 58.49% (31/53) malignant cells and a relatively weak expression of caspase-9 in 41.51% (22/53) malignant cells. The proportion of apoptotic cells in 31 malignant cases with strong caspase-9 expression (35.14 ± 3.42)% was significantly higher than that in 22 malignant cases with relatively weak caspase-9 expression (17.29 ± 7.62)% or in mesothelial cells (10.76 ± 4.21%; p < 0.05). Kaplan-Meier survival curves demonstrated that the patients with low caspase-9 expression showed significantly shorter survival (p < 0.05) than those with high caspase-9 expression. These findings suggest that immune clearance gastric carcinoma cells in ascites activated by caspase-9 helped to improve the prognosis of patients with gastric cancer.