Isolation of tumor spheres and mesenchymal stem-like cells from a single primitive neuroectodermal tumor specimen

PURPOSE

It has been reported that cancer stem cells (CSCs) can be isolated from primitive neuroectodermal tumor (PNET) specimens. Moreover, mesenchymal stem-like cells (MSLCs) have been isolated from Korean glioma specimens. Here, we tested whether tumor spheres and MSLCs can be simultaneously isolated from a single PNET specimen, a question that has not been addressed.

METHODS

We isolated single-cell suspensions from PNET specimens, then cultured these cells using methods for MSLCs or CSCs. Cultured cells were analyzed for surface markers of CSCs using immunocytochemistry and for surface markers of bone marrow-derived mesenchymal stem cells (BM-MSCs) using fluorescence-activated cell sorting (FACS). Tumor spheres were exposed to neural differentiation conditions, and MSLCs were exposed to mesenchymal differentiation conditions. Possible locations of MSLCs within PNET specimens were determined by immunofluorescence analysis of tumor sections.

RESULTS

Cells similar to tumor spheres and MSLCs were independently isolated from one of two PNET specimens. Spheroid cells, termed PNET spheres, were positive for CD133 and nestin, and negative for musashi and podoplanin. PNET spheres were capable of differentiation into immature neural cells and astrocytes, but not oligodendrocytes or mature neural cells. FACS analysis revealed that adherent cells isolated from the same PNET specimen, termed PNET-MSLCs, had surface markers similar to BM-MSCs. These cells were capable of mesenchymal differentiation. Immunofluorescence labeling indicated that some CD105(+) cells might be closely related to endothelial cells and pericytes.

CONCLUSION

We showed that both tumor spheres and MSLCs can be isolated from the same PNET specimen. PNET-MSLCs occupied a niche in the vicinity of the vasculature and could be a source of stroma for PNETs.

Comparison of dimensional reduction methods for detecting and visualizing novel patterns in human and marine microbiome

Using metagenomics to detect the global structure of microbial community remains a significant challenge. The structure of a microbial community and its functions are complicated because of not only the complex interactions among microbes but also their interactions with confounding environmental factors. Recently dimension reduction methods have been employed extensively to investigate the complex structure embedded in metagenomic profiles which summarize the abundance of functional or taxonomic categorizations in metagenomic studies. However, metagenomic profiles are not necessary to meet the "Assumption of Linearity" behind these methods. Therefore it is worth to investigate whether nonlinear methods are appropriate methods which can be utilized in metagenomic analysis. In this paper, we compare the applications of several methods, including two linear methods (Principle component analysis and nonnegative matrix factorization) and a nonlinear manifold learning method--Isomap on visualizing and analyzing metagenomic profiles. These methods are applied and compared on a taxonomic profile from 33 human gut metagenomes and a large-scale Pfam profile which are derived from 45 metagenomes in Global Ocean Sampling expedition. We find that all three methods can discover interesting structures of the taxonomic profile from human gut. Furthermore, Isomap identified a novel nonlinear structure of protein families. The relationships among the identified nonlinear components and environmental factors of global ocean are explored. The results indicate that nonlinear methods could be a complementary technique to current linear methods in analyzing metagenomic dataset.

Transventricular endoscopic fenestration of intrasellar arachnoid cyst

BACKGROUND

To manage arachnoid cysts, incorporation with the normal circulation is the single most important determinant of success. Although the postoperative cerebrospinal fluid leakage rate is 3.9% for all cases of transsphenoidal surgery, it is 21.4% for intrasellar arachnoid cysts.

OBJECTIVE

To present a safe, relatively easy, and effective treatment option for very rare intrasellar arachnoid cysts.

METHODS

We performed a prospective study of intrasellar cystic lesions without a solid portion. Endoscopic exploration and fenestration were performed for all lesions under neuronavigational guidance. We analyzed presenting symptoms, endocrinological status, and magnetic resonance images.

RESULTS

There were 2 male and 4 female patients with a mean age of 45 years (range, 27-67 years). All patients presented with the visual disturbance of bitemporal hemianopsia. Four patients had endocrinological symptoms including galactorrhea, dysmenorrhea, and diabetes insipidus. Endoscopic fenestration of the cyst was successfully performed in all patients. All patients were confirmed to have a pure cystic lesion, namely an arachnoid cyst. The follow-up period was 10 months on average (range, 6-12 months). Visual disturbance improved in 5 patients. Endocrinological problems persisted in all patients for 3 months and then normalized, with the exception of the patient with diabetes insipidus. There was no evidence of recurrence in any of the 6 patients in the 12-month postoperative imaging studies (median follow-up of 10 months). Two patients showed syndrome of inappropriate antidiuretic hormone at 2 and 4 weeks after the operation, but antidiuretic hormones recovered to normal levels after this time point.

CONCLUSION

Endoscopic fenestration of an intrasellar arachnoid cyst is a safe and simple procedure without serious complications.

Increased in vivo angiogenic effect of glioma stromal mesenchymal stem-like cells on glioma cancer stem cells from patients with glioblastoma

The presence of glioma stromal mesenchymal stem‑like cells (GS-MSLCs) in tumors from glioma patients has been previously reported. The mechanisms through which these cells function as a part of the glioma microenvironment, however, remain incompletely understood. We investigated the biological effects of GS-MSLCs on glioma cancer stem cells (gCSCs), testing the hypothesis that GS-MSLCs alter the biological characteristics of gCSCs. GS-MSLCs and gCSCs were isolated from different glioblastoma (GBM) specimens obtained from patients. In in vitro experiments, gCSCs were cultured alone or co-cultured with GS-MSLCs, and gCSCs cell counts were compared between the two groups. In addition, two groups of orthotopic GBM xenografts in mice were created, one using gCSCs from the monoculture group and one using gCSCs isolated from the co-culture group, and tumor volume and survival were analyzed. Furthermore, in vivo proliferation, apoptosis and vessel formation were examined using immunohistochemical analyses. In vitro cell counts for gCSCs co-cultured with GS-MSLCs increased 3-fold compared to gCSCs cultured alone. In orthotopic xenograft experiments, mice injected with gCSCs isolated from the co-culture group had significantly larger tumor volume, measured on day 40 after injection, and their survival times were shorter. Immunohistochemical analysis showed increased tumor expression of CD31, indicative of enhanced microvessel formation in mice injected with gCSCs co-cultured with GS-MSLCs compared to mice injected with gCSCs cultured alone. However, proliferation (PCNA) and apoptosis (TUNEL) markers showed no significant difference between the two groups. In conclusion, GS-MSLCs may influence the biological properties of gCSCs, shifting them towards a more aggressive status; moreover, increased angiogenesis may be a critical component of this mechanism.

Changes in the biological characteristics of glioma cancer stem cells after serial in vivo subtransplantation

PURPOSE

Currently, the interaction between the niche and glioma cancer stem cells (gCSCs) is gaining attention. However, there are few studies concerned with the effects of repeated exposure to a new microenvironment on gCSCs characteristics. In this study, serial in vivo subtransplantation was performed to create a new microenvironment. We evaluated and compared the biological characteristics of gCSCs after serial in vivo subtransplantation.

METHODS

We cultured gCSCs from human glioma specimens according to cultured gliomasphere methods. The isolated gCSCs were termed zero-generation gCSCs (G0-gCSCs). By subsequent serial subtransplantation, we obtained first-generation gCSCs (G1-gCSCs) and second-generation gCSCs (G2-gCSCs). We evaluated and compared the biological characteristics of G0-gCSCs, G1-gCSCs, and G2-gCSCs. The in vitro characteristics included the morphology, surface marker profiles, and neural differentiation capacity and the in vivo characteristics was the survival of mice xenografts. Additionally, brain sections were analyzed using PCNA, TUNEL, and CD31 staining.

RESULTS

We observed no significant differences in the in vitro characteristics of G0-gCSCs, G1-gCSCs, and G2-gCSCs. However, the survival time of mice glioma xenografts was significantly decreased upon serial subtransplantation. In addition, immunohistochemical analyses showed that the number of TUNEL(+) cells was significantly decreased while the number of CD31(+) cells was significantly increased with serial in vivo subtransplantation.

CONCLUSIONS

There were significant in vivo biological changes in gCSCs upon serial in vivo subtransplantation, which were shorter xenograft survival, increased angiogenesis, and decreased apoptosis. This study suggests that the repeated exposure to new microenvironments may affect the biological changes in gCSCs in vivo.

Exploiting the functional and taxonomic structure of genomic data by probabilistic topic modeling

In this paper, we present a method that enable both homology-based approach and composition-based approach to further study the functional core (i.e., microbial core and gene core, correspondingly). In the proposed method, the identification of major functionality groups is achieved by generative topic modeling, which is able to extract useful information from unlabeled data. We first show that generative topic model can be used to model the taxon abundance information obtained by homology-based approach and study the microbial core. The model considers each sample as a “document,” which has a mixture of functional groups, while each functional group (also known as a “latent topic”) is a weight mixture of species. Therefore, estimating the generative topic model for taxon abundance data will uncover the distribution over latent functions (latent topic) in each sample. Second, we show that, generative topic model can also be used to study the genome-level composition of “N-mer” features (DNA subreads obtained by composition-based approaches). The model consider each genome as a mixture of latten genetic patterns (latent topics), while each functional pattern is a weighted mixture of the “N-mer” features, thus the existence of core genomes can be indicated by a set of common N-mer features. After studying the mutual information between latent topics and gene regions, we provide an explanation of the functional roles of uncovered latten genetic patterns. The experimental results demonstrate the effectiveness of proposed method.

Abstract 2059: NADPH Oxidase 4 induced ROS regulates anoikis resistance through activation of Src and EGFR

Since cancer cells must overcome the anoikis for the metastasis, anoikis resistance is an important process for tumor progression and metastasis. To identify anoikis resistance mechanism, we performed mRNA microarray analysis with attached and suspended human lung epithelial adenocarcinoma A549 cells. Our microarray data reveals that Nox4 mRNA is up-regulated in the suspended cells. We evaluated both mRNA and protein levels of Nox4 and found that Nox4 is up-regulated in both mRNA and protein levels. In addition, higher levels of ROS are detected and Src activation was enhanced in suspended cells than attached cells. Interestingly, increased level of ROS in suspended cells was decreased by ROS scavengers or Nox4 inhibitors, leading to inactivation of Src and EGFR. Furthermore, knock-down of Nox4 by si-RNA specific for Nox4 resulted in inactivation of Src and EGFR. Because Src activation is not inhibited by EGFR inhibitor, Src activation appears to be independent on EGFR. In addition, si-RNA for Nox4 transfection decreased viability of cells in suspension. These results suggest that upon cell detachment, Nox4 expression is up-regulated and thus ROS levels are increased, which are important for activation of Src and EGFR, leading to sustained cell viability in the suspended cells. Therefore, we postulate that ROS generation through the Nox4 is an important process for anoikis resistance.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2059. doi:1538-7445.AM2012-2059

Cyclophosphamide-containing regimen (TCD) is superior to melphalan-containing regimen (MPT) in elderly multiple myeloma patients with renal impairment

Renal impairment (RI) is a frequent complication with higher incidence of infections and an important prognostic factor for survival. Melphalan clearance is renal function dependent whereas cyclophosphamide is renal function independent. We investigated which combination regimen should be selected between melphalan-combining regimen (MPT) or cyclophosphamide-combining regimen (TCD) in elderly multiple myeloma (MM) patients with RI. Between 2005 and 2009, 157 newly diagnosed MM patients with RI were included comparing MPT with TCD therapy as initial treatment. Seventy-four patients were given MPT regimen, and 83 patients were given TCD regimen. Baseline characteristics were similar between the MPT and TCD groups. Analysis of different cutoff levels between 25% and 75% quartiles using log-rank test determined that glomerular filtration rate (GFR), 40 ml/min/1.73 m(2) as the cutoff point, yielded the highest difference in event-free survival (EFS) and overall survival (OS). The MPT subgroup with low GFR (GFR <40 ml/min/1.73 m(2)) had poorer response rates than others. The incidence of neutropenia and infection with febrile neutropenia were higher in the MPT subgroup with low GFR than the others (p = 0.016, p < 0.001). Furthermore, mortality due to the infection was higher in the MPT subgroup with low GFR than the others (p < 0.001). EFS was lower in the MPT subgroup with low GFR than the others (p < 0.001). OS was lower in the MPT subgroup with low GFR than the others (p < 0.001). In newly diagnosed elderly MM patients with RI, TCD regimen would be an effective and tolerable treatment option due to the combination of cyclophosphamide independent to renal function and dexamethasone effective for RI.

Correlation between the digital cervicography and pathological diagnosis performed at private clinics in Korea

OBJECTIVE

To evaluate the correlation tendency between abnormal findings of digital cervicography and cervical pathology at private clinics in Korea.

METHODS

Abnormal finding of digital cervicography performed at private clinics in Korea between January 1, 2010 and May 31, 2012 were analysed retrospectively. The patient's age, abnormal findings of digital cervicography, cervical cytology, human papillomaviru (HPV) test and cervical pathology were investigated and the rate of agreement between abnormal finding of digital cervicography and cervical pathology results was calculated. Abnormal findings of digital cervicography were divided into 4 categories: atypical, compatible with CIN1, compatible with CIN2/3 and compatible with cancer.

RESULTS

The study group was composed of 1547 women with a mean (range) age of 37.4 (14-91 years). The agreement rate between abnormal findings of digital cervicography and cervical pathology was 52.0% in "compatible with CIN1", 78.9% in "compatible with CIN2/3", and 90.2% in "compatible with cancer".

CONCLUSIONS

Abnormal findings of digital cervicography were highly concordant with cervical intraepithelial neoplasia (CIN) and cancer examined at outpatient clinics in Korea. Therefore, abnormal interpretations of digital cervicography can be used as an excellent auxiliary technique with cervical cytology for CIN and cancer.

Association of SMAD2 polymorphisms with bone mineral density in postmenopausal Korean women

In a candidate gene association study, we found that SMAD2 promoter alleles and haplotypes were significantly associated with bone mineral density (BMD) at the lumbar spine and various proximal femur sites. Our results suggest that SMAD2 polymorphisms may be one of genetic determinants of BMD in postmenopausal women.

INTRODUCTION

SMAD2, which is the specific intracellular transducer of TGF-ß, is thought to participate in bone metabolism by playing a critical role in the development and function of osteoclasts and osteoblasts. We performed association analyses of the genetic variation in SMAD2 to ascertain the contribution of this gene to BMD and risk of osteoporotic fracture.

METHODS

We selected three SMAD2 promoter single-nucleotide polymorphisms (SNPs) based on heterozygosity and validation status. Postmenopausal Korean women (n = 1,329) were genotyped for these SNPs, and their BMD and risk of fractures were assessed. BMD at the lumbar spine and proximal femur was measured using dual-energy X-ray absorptiometry. P values were corrected for multiple testing by the effective number of independent marker loci (P (cor)).

RESULTS

We found that SMAD2 -35302C>T, -34952A>G, and ht2 were significantly associated with BMD at both the lumbar spine and femur neck (P (cor) = 0.020-0.046), whereas SMAD2 -36201A>G and ht1 affected the femur neck BMD (P (cor) = 0.018-0.031). The genetic effects of these three polymorphisms on BMD at the lumbar spine and femur neck were risk-allele dependent in additive model. The three polymorphisms and two hts were also significantly associated with BMD at other proximal femur sites, such as the total femur, trochanter, and femur shaft (P (cor) = 0.001-0.046). However, none of the polymorphisms or hts was associated with an increased risk of fracture.

CONCLUSIONS

Our results suggest that SMAD2 polymorphisms may be one of genetic determinants of BMD in postmenopausal women.

Dynamic biclustering of microarray data by multi-objective immune optimization

Abstract

Borderline mucinous tumor arising in a paratubal cyst: a case report

BACKGROUND

Paratubal borderline tumors (PBTs) are found incidentally at frozen section or permanant pathology, and are extremely rare. We describe the first case of a paratubal borderline mucinous tumor (PBMT).

CASE REPORT

A 20-year-old woman was referred with a complex right adnexal mass on pelvic sonogram. She underwent laparoscopic paratubal cyst enucleation. We used an endobag for cyst extraction. Cyst rupture or tearing of the endobag in the laparoscopic field was absent. Frozen section analysis was reported as a borderline mucinous tumor of low malignant potential. Currently, she has had no evidence of disease recurrence after a laparoscopic fertility-sparing staging procedure.

CONCLUSION

A proper preoperative differential diagnosis of an adnexal mass is difficult. Thus, laparoscopy is needed in large or symptomatic cysts. Although growth, torsion and malignancy are rare in paratubal cysts, the possibility of tumor seeding should be excluded with use of an endobag.

Clinical analysis of borderline ovarian tumors

PURPOSE

The goal of this study was to evaluate the incidence and clinical features of borderline ovarian tumors (BOTS).

METHODS

We retrospectively performed chart reviews of 22 patients with BOTS who were diagnosed and treated in the university medical center from 1998 to 2009 inclusively.

RESULTS

BOTS among ovarian pathology in our hospital were detected in 22 patients (1.79%). The mean age was 50 years, range (20-90). Post surgical FIGO staging was Stage I = 86.4%, and Stage II = 13.6%. The most common histologic subtype was mucinous (59%). Five patients (22.7%) had a unilocular cyst at ultrasonography. Conservative surgery was performed in 31.8%. One patient of them had normal spontaneous delivery after term pregnancy. Two patients had a recurrence. One patient with recurrent disease underwent transformation to invasive cancer and died 35 months after the initial diagnosis.

CONCLUSION

Clinicians should warn patients about the early relapse of BOTS and these patients may need careful follow-up due to the possibility of recurrences.

Unexpected synchronous follicular lymphoma of paraaortic and pelvic lymph nodes in a patient with endometrial carcinoma: a case report

BACKGROUND

Multiple neoplasms in a patient occur rarely. There has only been one case report about synchronous endometrial carcinoma and follicular lymphoma of the paraaortic and pelvic lymph node (LN) until now.

CASE REPORT

The patient was 64 years old and had vaginal spotting for four months. She was diagnosed with endometrioid endometrial carcinoma by endometrial biopsy. In intraoperative inspection, the whole paraaortic and pelvic LN had formed into a massive tumor bundle following the aorta and iliac vessels. The diagnosis was endometrial carcinoma FIGO Stage IB with synchronous follicular lymphoma Stage III. We performed adjuvant chemotherapy and radiotherapy. Currently, the patient has no evidence of recurrence for either carcinoma.

CONCLUSION

Lymph node dissection was included in the staging and debulking operation of the endometrial carcinoma. An inaccurate result of the frozen section can not rule out metastasis of endometrial carcinoma and surgeons can fall into a dilemma regarding treatment.

A case of primary ovarian adenomyoma mimicking ovarian malignancy

Adenomyoma is a benign tumor composed of smooth muscle and benign endometrium. These tumors typically originate within the uterus. An extrauterine adenomyoma is an extremely rare entity. After an extensive literature search, only four cases of primary ovarian adenomyoma appear to have thus far been reported. Here, we report a case of ovarian adenomyoma in a 39-year-old woman mimicking malignant neoplasma of the ovary, along with a brief literature review.

Parovarian tumors of borderline malignancy

The incidence of a parovarian tumor is 10-20% of all uterine adnexal masses, however, it is benign in most cases, and a borderline or malignant tumor is extremely rare. The classification of disease stage and treatment is still controversial owing to its scarcity. We have managed one mucinous and two serous cystadenomas of borderline malignancy originating from paraovarian cysts in our institute over ten year. We report and discuss the cases herein.

Polymorphisms in the Matrilin-1 gene and risk of mandibular prognathism in Koreans

Previous linkage analysis of an Asian population proposed possible candidate genes for mandibular prognathism, such as Matrilin-1 (cartilage matrix protein). To investigate the association between the single-nucleotide polymorphisms (SNPs) in Matrilin-1 and mandibular prognathism, we investigated three sequence variants (-158 T>C, 7987 G>A, 8572 C>T) in 164 mandibular prognathism patients and 132 control individuals with a normal occlusion. The results showed that the 8572 TT genotypes in Matrilin-1 showed increased risk of mandibular prognathism (OR = 9.28, 95% Cl = 1.19~197.57, P < 0.05), whereas the 7987 AA genotype showed a protective effect for mandibular prognathism (OR = 0.16, 95% Cl = 0.05~0.47, P < 0.05). Genotyping results showed that the Matrilin-1 polymorphism haplotype TGC (ht4; 158T, 7987G, and 8572C alleles) had a pronounced risk effect for mandibular prognathism compared with controls (OR = 5.16, 95% Cl = 2.03~13.93, P < 0.01). The results suggest that polymorphisms in Matrilin-1 could be used as a marker for genetic susceptibility to mandibular prognathism.

Fracture, bone mineral density, and the effects of calcitonin receptor gene in postmenopausal Koreans

SUMMARY

In a candidate gene association study, we found that the variations of calcitonin receptor (CALCR) gene were related to the risk of vertebral fracture and increased bone mineral density (BMD).

INTRODUCTION

Calcitonins through calcitonin receptors inhibit osteoclast-mediated bone resorption and modulate calcium ion excretion by the kidney and also prevent vertebral bone loss in early menopause.

METHODS

To identify genetically susceptible factors of osteoporosis, we discovered the variations in CALCR gene, genotyped in Korean postmenopausal women (n = 729), and examined the potential involvement of seven single-nucleotide polymorphism (SNPs) and their haplotypes in linkage disequilibrium block (BL_hts).

RESULTS

The SNPs, +43147G > C (intron 7), +60644C > T (exon13, 3' untranslated region), and their haplotypes, BL2_ht1 and BL2_ht2, showed a significant association with risk of vertebral fracture (p = 0.048-0.004) and BL2_ht1 showed a highly significant protective effect. Moreover, the polymorphism +60644C > T showed a highly significant association with BMD at both lumbar spine and femoral neck. The subjects carrying CC and CT genotypes with the SNP, +60644C > T, had higher BMD values at the lumbar spine (p = 0.01-0.001) and femoral neck (p = 0.025-0.009).

CONCLUSION

These results indicate that the CALCR gene may regulate bone metabolism, and +60644C > T in the CALCR gene may genetically modulate bone phenotype.

Association of TWIST1 gene polymorphisms with bone mineral density in postmenopausal women

A novel polymorphism (+1871A>G) in the 3' flanking region and haplotypes were significantly associated with reduced osteoporosis risk and enhanced bone mineral density (BMD). These results suggest that TWIST1 may be a useful genetic marker for osteoporosis. Our results provide preliminary evidence supporting an association of TWIST1 with osteoporosis in postmenopausal women.

INTRODUCTION

TWIST1, a basic helix-loop-helix (bHLH) transcription factor, has been implicated in cell lineage determination and differentiation.

METHODS

To address the genetic variations in the TWIST1 gene associated with osteoporosis, we investigated the potential involvement of three TWIST1 single-nucleotide polymorphisms (SNPs) in osteoporosis in 729 postmenopausal women. BMD was measured using dual-energy X-ray absorptiometry.

RESULTS

A novel polymorphism in the 3' flanking region (+1871A>G) was significantly associated with osteoporosis risk (p = 0.007-0.008) and also in multiple comparison (p = 0.02). Consistent with these results, haplotype analysis showed that Block1_ht2 had protective effects in the dominant and additive model (p = 0.006-0.007). Specifically, the +1871A>G polymorphism was overdominantly associated with higher BMD values of the femoral neck (p = 0.039).

CONCLUSION

These results suggest that TWIST1 may be a useful genetic marker for osteoporosis and may have a role on bone metabolism in humans. Our results provide preliminary evidence supporting an association of TWIST1 with osteoporosis in postmenopausal women.

Exploratory analysis of protein translation regulatory networks using hierarchical random graphs

Abstract

Electrochemical fabrication of Pt-Au-WO3 electrodes for direct methanol fuel cell

Pt-Au-WO3 ternary electrodes with various compositions were synthesized by electrochemical method from a mixture of H2PtCl6 aqueous solution, HAuCl4 aqueous solution, and W-peroxo complex. Their electrocatalytic activities for methanol oxidation were investigated. Film composition was controlled by varying the concentration of each component in electrolytes. Morphology and compositional analyses of the synthesized films were performed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The catalytic activity and initial behavior of current density for methanol oxidation of the synthesized films were measured using cyclic voltammetry (CV) and chronoamperometry (CA) in a mixture of 0.5 M H2SO4 and 0.5 M CH3OH solution. Electrocatalytic activity for CO oxidation was also evaluated in 0.5 M H2SO4 solution. The activities of various electrodes for methanol oxidation were found to be strongly dependent on film composition. Pt-Au-WO3 electrodes exhibited higher activity for CO oxidation than pure Pt. The addition of proper amount of Au and WO3 significantly improved catalytic activity for methanol oxidation.