Anti-SEMA3A Antibody: A Novel Therapeutic Agent to Suppress Glioblastoma Tumor Growth / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Glioblastoma (GBM) is classified as one of the most aggressive and lethal brain tumor. Great strides have been made in understanding the genomic and molecular underpinnings of GBM, which translated into development of new therapeutic approaches to combat such deadly disease. However, there are only few therapeutic agents that can effectively inhibit GBM invasion in a clinical framework. In an effort to address such challenges, we have generated anti-SEMA3A monoclonal antibody as a potential therapeutic antibody against GBM progression. MATERIALS AND METHODS: We employed public glioma datasets, Repository of Molecular Brain Neoplasia Data and The Cancer Genome Atlas, to analyze SEMA3A mRNA expression in human GBM specimens. We also evaluated for protein expression level of SEMA3A via tissue microarray (TMA) analysis. Cell migration and proliferation kinetics were assessed in various GBM patient-derived cells (PDCs) and U87-MG cell-line for SEMA3A antibody efficacy. GBM patient-derived xenograft (PDX) models were generated to evaluate tumor inhibitory effect of anti-SEMA3A antibody in vivo. RESULTS: By combining bioinformatics and TMA analysis, we discovered that SEMA3A is highly expressed in human GBM specimens compared to non-neoplastic tissues. We developed three different anti-SEMA3A antibodies, in fully human IgG form, through screening phage-displayed synthetic antibody library using a classical panning method. Neutralization of SEMA3A significantly reduced migration and proliferation capabilities of PDCs and U87-MG cell line in vitro. In PDX models, treatment with anti-SEMA3A antibody exhibited notable tumor inhibitory effect through down-regulation of cellular proliferative kinetics and tumor-associated macrophages recruitment. CONCLUSION: In present study, we demonstrated tumor inhibitory effect of SEMA3A antibody in GBM progression and present its potential relevance as a therapeutic agent in a clinical framework.

STAT3 inhibits the degradation of HIF-1alpha by pVHL-mediated ubiquitination

Hypoxia-inducible factor 1alpha (HIF-1alpha) is rapidly degraded by the ubiquitin-proteasome pathway under normoxic conditions. Ubiquitination of HIF-1alpha is mediated by interaction with von Hippel-Lindau tumor suppressor protein (pVHL). In our previous report, we found that hypoxia-induced active signal transducer and activator of transcription3 (STAT3) accelerated the accumulation of HIF-1alpha protein and prolonged its half-life in solid tumor cells. However, its specific mechanisms are not fully understood. Thus, we examined the role of STAT3 in the mechanism of pVHL-mediated HIF-1alpha stability. We found that STAT3 interacts with C-terminal domain of HIF-1alpha and stabilizes HIF-1alpha by inhibition of pVHL binding to HIF-1alpha. The binding between HIF-1alpha and pVHL, negative regulator of HIF-1alpha stability, was interfered dose-dependently by overexpressed constitutive active STAT3. Moreover, we found that the enhanced HIF-1alpha protein levels by active STAT3 are due to decrease of poly-ubiquitination of HIF-1alpha protein via inhibition of interaction between pVHL and HIF-1alpha. Taken together, our results suggest that STAT3 decreases the pVHL-mediated ubiquitination of HIF-1alpha through competition with pVHL for binding to HIF-1alpha, and then stabilizes HIF-1alpha protein levels.

LYR71, a derivative of trimeric resveratrol, inhibits tumorigenesis by blocking STAT3-mediated matrix metalloproteinase 9 expression

Tumor migration/invasion is the main cause of tumor progression and STAT3 is needed to enhance tumor migration/invasion by up-regulating MMP-9. Thus, agents that inhibit STAT3 activation may be used as an anticancer drug. We present herein that 6-methyl-2-propylimino-6, 7-dihydro-5H-benzo [1, 3]-oxathiol- 4-one (LYR71) , a derivative of trimeric resveratrol, has an anticancer activity through inhibition of STAT3 activation. We found that LYR71 suppressed STAT3 activation and inhibited the expression and activity of MMP-9 in RANTES-stimulated breast cancer cells. In addition, LYR71 reduced RANTES-induced MMP-9 transcripts by blocking STAT3 recruitment, dissociating p300 and deacetylating histone H3 and H4 on the MMP-9 promoter. Furthermore, LYR71 inhibited tumor migration/invasion in RANTES-treated breast cancer cells and consequently blocked tumor progression in tumor-bearing mice. Taken together, the results of this study suggest that LYR71 can be therapeutically useful due to the inhibition effect of STAT3-mediated MMP-9 expression in breast cancer cells.

Korean Standardization of General Medical Health Rating on Dementia Patients

Concurrent medical problem is common in dementia patients and critical to their care. Despite its importance, there was no bedside global rating scale for the seriousness of medical comorbidity. Lykestos et al. newly developed a reliable bedside scale, the General Medical Health Rating(GMHR). The objective of this study was to standardize the GMHR in form of Korean version(KGMHR). The study population consisted of 35 dementia patients in nursing home. Rating was performed by 1 physician and 2 nurses. Forty percent(14/35) of patients had one or more unstable medical illnesses. KGMHR ratings no more than 3 were 71.5%(25/35) of patients. The value of interrater reliability coefficient alpha was 0.9121. Correlations between KGMHR ratings and number of unstable medi-cal illnesses were high(r=-0.487, p<0.01). KGMHR ratings were also correlated with number of medications being taken for comorbid conditions(r=-0.542, p<0.01). In conclusion, KGMHR is a very reliable and simple rating scale for medical comorbidity in dementia patients. So the KGMHR could be a useful tool for evaluation of comorbidity in dementia patients. To verify the prognostic value of KGMHR, further large sized long-term study are needed.

The Multidimensional Evaluation of Dementia Patients and the Correlation among Measures

OBJECTIVES: Behavioral problem and functional impairment in addition to cognitive impairment are induced, and the medical comorbidity is common in dementia patients. Thus the evaluation of these domains is needed for the management of dementia patients. This study presents a method practically and easily assessing above all dimensions, and analyzes the results. METHODS: The multidimensional evaluating method consists of one general staging measure (GDS) and four measures(MMSE, B-ADL, BEHAVE-AD, GMHR) evaluating four domains;cognition, activities of daily living, behavior, and medical comorbidity. These measures are administered to 29 dementia patients(Alzheimer's dementia 21, mixed or vascular dementia 9) admitted in a long-term care residence of dementia patients. The correlation of measures and the difference of the type of dementia, sex, and age are analysed by Pearson correlation coefficient and independent t-test respectively. RESULTS & CONCLUSIONS: In the correlation of scales, the score of MMSE was significantly correlated to the score of B-ADL in Alzheimer's dementia patient group(p<0.05). The score of B-ADL was significantly higher(p<0.05) and the score of GMHR was statistically insignificantly higher in Alzheimer's dementia patient group than mixed or vascular dementia patient group. The sex and age was unrelated to cognitive or functional ability. This multidimensional evaluating method, including the assessment of the medical comorbidity, is thought to be convenient to apply in the long-term care residence of dementia patients, and be of practical help to the management of dementia patients.

Identification of Retroviral Vectors Producing High Viral Titer

Retroviral vector provide a highly efficient method for gene transfer into eukaryotic cells. This vector system can be divided into two components; the retroviral vector itself and the retroviral packaging cell line. The key improvement in the design of these two components are. focused on two aspects; the reduction of helper virus production and high titer-virus. We used PA317 for retrovirus packaging cell line, for its high producibility of viral titer, To test the ability of the vectors to generate high titer-virus, we have chosen four different retroviral vectors; LN, LNSX, LNCX and LXSN. To test easily the viral titer, we have made recombinant construction with CD4 and CD8, checked their viral titer and stained their surface expression. LXSN which contain SV40 early promoter in front of leo gene showed best results in viral transient transfection assay, dot blot assay and surface expression. In addition, recombinant containing CD8 generally showed much higher viral titration and surface expression than CD4.

PCR Approach for Detection and Typing of Epidermodysplasia Verruciformis-associated Human Papillomavirus Types

Warts, or verrucae, are benign epithelial proliferations of the skin and mucosa caused by infection with human papillomaviruses (HPV). It is now recognized that there are many different HPV types. Especially type3 is most frequently observed in flat wart. Other types, such as type2, 10, 14, 27, 28, 29, 38, and 41 are rarely encounted in flat wart. We describe here a simple and economic method for detection and identification of epidermodysplasia verruciformis-associated HPV. The method is based on polymerase chain reaction (PCR) amplification and restriction analysis. The method has been developed with cloned HPV DNA and DNA from clinical samples. Clinical samples are from either frozen tissue or paraffin-embedded tissue. Genomic fragments were obtained from two different HPV types (3 and 10). The amplification fragments were identified by a form of miniature fingerprinting, with a set of restriction enzymes that gave a unique digestion pattern for each HPV type. We have tested 74 clinical samples. Only type3 among these clinical samples is detected, and one sample is involved in neither type3 nor type10.