• Radiation Oncology Journal
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• v.5 no.1
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• pp.23-30
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• 1987

Thirty eight patients with stage I and II primary gastrointestinal non-Hodgkin's lymphoma were treated in the Department of Therapeutic Radiology, Seoul National University Hospital between 1979 and 1984. There were 6 systemic disseminations during radiotherapy, and the overall failure rate were $31\%$ in the cases with tumor bulk less than 5cm in diameter before radiotherapy and $75\%$ in the cases with tumor bulk greater than 5cm in diameter (p <0,05). The overall 5 year survival rate were $69.2\%$ in 28 patients who completed radiotherpay and $72\%$ in 24 patients with tumor bulk less than 5cm in diameter (small or no tumor bulk). The 5 year disease free survival rate were $71\%$ in cases with tumor bulk less than 5cm in diameter and $25\%$ in cases with tumor bulk greater than 5cm in diameter (p<0.01). But the intitial stage was not related with treatment result in all cases or subgroups of cases. Thus the cases with small or no tumor bulk were shown to be curable with combined surgery and postoperative radiotherapy, but for the control of the cases with large tumor bulk that had a guarded prognosis combined radiotherapy and chemotherapy should be tried.

• BMB Reports
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• v.50 no.6
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• pp.283-284
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• 2017

Single cell transcriptome analysis is a powerful tool for defining cell types or sub-populations within a heterogeneous bulk population. Tumor-associated microenvironment is a complex ecosystem consisting of numerous cell types that support tumor growth, angiogenesis, immune evasion, and metastasis. With the success of checkpoint inhibitors targeting the immune cell compartment, tumor microenvironment is emerging as a potential anti-cancer target, and understanding it has become an imminent subject in cancer biology.

• BMB Reports
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• v.51 no.7
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• pp.319-326
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• 2018

Increasing evidence suggests that cancer stem cell (CSC) theory represents an important mechanism underlying the observed failure of existing therapeutic modalities to fully eradicate cancers. In addition to their more established role in maintaining minimal residual disease after treatment and forming the new bulk of the tumor, CSCs might also critically contribute to tumor recurrence and metastasis. For this reason, specific elimination of CSCs may thus represent one of the most important treatment strategies. Emerging evidence has shown that CSCs have a different metabolic phenotype to that of differentiated bulk tumor cells, and these specific metabolic activities directly participate in the process of CSC transformation or support the biological processes that enable tumor progression. Exploring the role of CSC metabolism and the mechanism of the metabolic plasticity of CSCs has become a major focus in current cancer research. The targeting of CSC metabolism may provide new effective therapies to reduce the risk of recurrence and metastasis. In this review, we summarize the most significant discoveries regarding the metabolism of CSCs and highlight recent approaches in targeting CSC metabolism.

• Brain Tumor Research and Treatment
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• v.6 no.2
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• pp.97-100
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• 2018

Meningioma is relatively common, benign, and extra-axial tumor accounting for about 20% of primary brain and spinal cord tumors. The World Health Organization (WHO) classified these tumors into Grade I (benign), Grade II (atypical), and Grade III (anaplastic) meningioma. Grade I meningioma which is slowly growing tumor and have some rare subtypes. Among them, metaplastic subtype is defined as a tumor containing focal or widespread mesenchymal components including osseous, cartilaginous, lipomatous, myxoid or xanthomatous tissue, singly or in combinations. We report a rare metaplastic meningioma overspreading nearly whole cerebral convexity from main extra-axial tumor bulk in the parietal lobe.

• Molecules and Cells
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• v.46 no.2
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• pp.99-105
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• 2023

Tumors are surrounded by a variety of tumor microenvironmental cells. Profiling individual cells within the tumor tissues is crucial to characterize the tumor microenvironment and its therapeutic implications. Since single-cell technologies are still not cost-effective, scientists have developed many statistical deconvolution methods to delineate cellular characteristics from bulk transcriptome data. Here, we present an overview of 20 deconvolution techniques, including cutting-edge techniques recently established. We categorized deconvolution techniques by three primary criteria: characteristics of methodology, use of prior knowledge of cell types and outcome of the methods. We highlighted the advantage of the recent deconvolution tools that are based on probabilistic models. Moreover, we illustrated two scenarios of the common application of deconvolution methods to study tumor microenvironments. This comprehensive review will serve as a guideline for the researchers to select the appropriate method for their application of deconvolution.

• Molecules and Cells
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• v.39 no.12
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• pp.847-854
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• 2016

The early landmark discoveries in cancer metabolism research have uncovered metabolic processes that support rapid proliferation, such as aerobic glycolysis (Warburg effect), glutaminolysis, and increased nucleotide biosynthesis. However, there are limitations to the effectiveness of specifically targeting the metabolic processes which support rapid proliferation. First, as other normal proliferative tissues also share similar metabolic features, they may also be affected by such treatments. Secondly, targeting proliferative metabolism may only target the highly proliferating "bulk tumor" cells and not the slowergrowing, clinically relevant cancer stem cell subpopulations which may be required for an effective cure. An emerging body of research indicates that altered metabolism plays key roles in supporting proliferation-independent functions of cancer such as cell survival within the ischemic and acidic tumor microenvironment, immune system evasion, and maintenance of the cancer stem cell state. As these aspects of cancer cell metabolism are critical for tumor maintenance yet are less likely to be relevant in normal cells, they represent attractive targets for cancer therapy.

• Genomics & Informatics
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• v.20 no.1
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• pp.13.1-13.4
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• 2022

A major issue in the use of immune checkpoint inhibitors is their lack of efficacy in many patients. Previous studies have reported that the T cell inflamed signature can help predict the response to immunotherapy. Thus, many studies have investigated mechanisms of immunotherapy resistance by defining the tumor microenvironment based on T cell inflamed and non-T cell inflamed subsets. Although methods of calculating T cell inflamed subsets have been developed, valid screening tools for distinguishing T cell inflamed from non-T cell inflamed subsets using gene expression data are still needed, since general researchers who are unfamiliar with the details of the equations can experience difficulties using extant scoring formulas to conduct analyses. Thus, we introduce TcellInflamedDetector, an R package for distinguishing T cell inflamed from non-T cell inflamed samples using cancer gene expression data via bulk RNA sequencing.

• Genomics & Informatics
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• v.17 no.1
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• pp.3.1-3.4
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• 2019

Intratumor heterogeneity within a single tumor mass is one of the hallmarks of malignancy and has been reported in various tumor types. The molecular characterization of intratumor heterogeneity in breast cancer is a significant challenge for effective treatment. Using single-cell RNA sequencing (RNA-seq) data from a public resource, an ERBB pathway activated triple-negative cell population was identified. The differential expression of three subtyping marker genes (ERBB2, ESR1, and PGR) was not changed in the bulk RNA-seq data, but the single-cell transcriptomes showed intratumor heterogeneity. This result shows that ERBB signaling is activated using an indirect route and that the molecular subtype is changed on a single-cell level. Our data propose a different view on breast cancer subtypes, clarifying much confusion in this field and contributing to precision medicine.

• Genomics & Informatics
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• v.16 no.4
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• pp.17.1-17.6
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• 2018

Tumor heterogeneity, the cellular mosaic of multiple lineages arising from the process of clonal evolution, has continued to thwart multi-omics analyses using traditional bulk sequencing methods. The application of single-cell sequencing, in concert with existing genomics methods, has enabled high-resolution interrogation of the genome, transcriptome, epigenome, and proteome. Applied to cancers, these single-cell multi-omics methods bypass previous limitations on data resolution and have enabled a more nuanced understanding of the evolutionary dynamics of tumor progression, immune evasion, metastasis, and treatment resistance. This review details the growing number of novel single-cell multi-omics methods applied to tumors and further discusses recent discoveries emerging from these approaches, especially in regard to immunotherapy.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1919-1927
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• 2006

Tumor cells genetically engineered to secrete cytokines are effective in tumor therapy, but various unexpected side effects are observed, which may result from the bulk activation of various bystander cells. In this study, we tested tumor vaccines expressing various membrane-bound forms of IL-2 (mbIL-2) on MethA fibrosarcoma cells to focus antitumor immune responses to CTL. Chimeric forms of IL-2 with whole CD4, deletion forms of CD4, and TNF were expressed on the tumor cell surface, respectively. Tumor clones expressing mbIL-2 or secretory form of IL-2 were able to support the cell growth of CTLL-2, an IL-2-dependent T cell line, and the proliferation of spleen cells from 2C TCR transgenic mice that are responsive to the $p2Ca/L^d$ MHC class I complex. Expression of mbIL-2 on tumor cells reduced the tumorigenicity of tumor cells, and the mice that once rejected the live IL-2/TNF tumor clone acquired systemic immunity against wild-type MethA cells. The IL-2/TNF clone was inferior to other clones in tumor formation, and superior in the stimulation of the CD8+ T cell population in vitro. These results suggest that the IL-2/TNF clone is the best tumor vaccine, and may stimulate CD8+ T cells by direct priming. Expression of IL-2/TNF on tumor cells may serve as an effective gene therapy method to ameliorate the side effects encountered in the recombinant cytokine therapy and the conventional cytokine gene therapy using the secretory form of IL-2.