Publications by authors named "Bu-Nam Jeon"

Immune checkpoint inhibitors have substantial advanced tumor treatment, but their limited benefits and strong responses in only a subset of patients remain challenging. In this study, we explored the immunomodulatory function of contactin-4 (CNTN4). CNTN4 was highly expressed in tumor tissues, and expression impaired the antitumor function of T cells.

View Article and Find Full Text PDF

Immune checkpoint inhibitor (ICI) clinically benefits cancer treatment. However, the ICI responses are only achieved in a subset of patients, and the underlying mechanisms of the limited response remain unclear. 160 patients with non-small cell lung cancer treated with anti-programmed cell death protein-1 (anti-PD-1) or anti-programmed death ligand-1 (anti-PD-L1) are analyzed to understand the early determinants of response to ICI.

View Article and Find Full Text PDF

Disruption of the skin microbial balance can exacerbate certain skin diseases and affect prognosis and treatment. Changes in the distribution and prevalence of certain microbial species on the skin, such as (SA), can impact the development of severe atopic dermatitis (AD) or psoriasis (Pso). A dysfunctional skin barrier develops in AD and Pso due to SA colonization, resulting in keratinization and chronic or progressive chronic inflammation.

View Article and Find Full Text PDF

The factor binding inducer of short transcripts-1 (FBI-1) is a POZ-domain Kruppel-like (POK) family of transcription factors and is known as a proto-oncogene or tumor suppressor in various carcinomas. However, the role of FBI-1 on epithelial-to-mesenchymal transition (EMT) and invasiveness in lung cancer remains unknown. Preliminarily, clinical data such as tissue microarray, Kaplan-Meier, and Oncomine were analyzed to confirm the correlation between lung cancer metastasis and FBI-1.

View Article and Find Full Text PDF

Zbtb7c is a proto-oncoprotein that controls the cell cycle and glucose, glutamate, and lipid metabolism. Zbtb7c expression is increased in the liver and white adipose tissues of aging or high-fat diet-fed mice. Knockout or knockdown of Zbtb7c gene expression inhibits the adipocyte differentiation of 3T3-L1 cells and decreases adipose tissue mass in aging mice.

View Article and Find Full Text PDF

Colorectal cancer (CRC) is among the leading causes of cancer-related death in the world. The development of CRC is associated with smoking, diet, and microbial exposure. Previous studies have shown that dysbiosis of the gut microbiome affects cancer development, because it leads to inflammation and genotoxicity.

View Article and Find Full Text PDF

The gut microbiome can influence the development of tumours and the efficacy of cancer therapeutics; however, the multi-omics characteristics of antitumour bacterial strains have not been fully elucidated. In this study, we integrated metagenomics, genomics and transcriptomics of bacteria, and analyses of mouse intestinal transcriptome and serum metabolome data to reveal an additional mechanism by which bacteria determine the efficacy of cancer therapeutics. In gut microbiome analyses of 96 samples from patients with non-small-cell lung cancer, Bifidobacterium bifidum was abundant in patients responsive to therapy.

View Article and Find Full Text PDF

Epithelial-mesenchymal transition (EMT) is a major cellular process in which epithelial cells lose cell polarity and cell-cell adhesion and become motility and invasiveness by transforming into mesenchymal cells. Catechol is one of the natural compounds present in fruits and vegetables and has various pharmacological and physiological activities including anti-carcinogenic effects. However, the effects of catechol on EMT has not been reported.

View Article and Find Full Text PDF

Dysregulated matrix metalloproteinase (MMP) gene expression is a major cause of the degradation of lung tissue that is integral to emphysema pathogenesis. Cigarette smoking (CS) increases MMP gene expression, a major contributor to emphysema development. We previously reported that Zbtb7c is a transcriptional repressor of several Mmp genes (Mmps-8, -10, -13, and -16).

View Article and Find Full Text PDF

The protein deacetylase SIRT1 is crucial to numerous physiological processes, such as aging, metabolism, and autoimmunity, and is repressed by various transcription factors, including HIC1. Conversely, we found that HIC2, which is highly homologous to HIC1, is a transcriptional activator of SIRT1 due to opposite activity of the intermediate domains of the two homologs. Importantly, this relationship between HIC2 and SIRT1 could be important for cardiac development, where both proteins are implicated.

View Article and Find Full Text PDF

Gluconeogenesis is essential for blood glucose homeostasis during fasting and is regulated by various enzymes, which are encoded by gluconeogenic genes. Those genes are controlled by various transcription factors. Zinc finger and BTB domain-containing 7c (Zbtb7c, also called Kr-pok) is a BTB-POZ family transcription factor with proto-oncogenic activity.

View Article and Find Full Text PDF

Correct temporal and spatial control of actin dynamics is essential for the cytotoxic T cell effector function against tumor cells. However, little is known whether actin engineering in tumor-targeted T cells can enhance their antitumor responses, thereby potentiating the adoptive T cell therapy. Here, we report that TAGLN2, a 22-KDa actin-stabilizing protein which is physically associated with lymphocyte function-associated antigen-1 (LFA-1), potentiates the CD8 T cells to kill the intercellular adhesion molecule-1 (ICAM-1)-positive/OVA-presenting E0771 cells, but not ICAM-1-negative OVA-B16F10 cells, suggesting an 'inside-out' activation of LFA-1, which causes more efficient immunological synapse formation between T cells and tumor cells.

View Article and Find Full Text PDF

Even in the face of physiological DNA damage or expression of the tumor suppressor protein p53, B cell CLL/lymphoma 6 (BCL6) increases proliferation and antagonizes apoptotic responses in B cells. BCL6 represses transcription and also appears to inactivate p53 at the protein level, and additional findings have suggested negative mutual regulation between BCL6 and p53. Here, using knockout mice, HEK293A and HCT116 cells, and site-directed mutagenesis, we found that BCL6 interacts with p53 and thereby inhibits acetylation of Lys-132 in p53 by E1A-binding protein p300 (p300), a modification that normally occurs upon DNA damage-induced cellular stress and whose abrogation by BCL6 diminished transcriptional activation of p53 target genes, including that encoding caspase-1.

View Article and Find Full Text PDF

Microvilli on T cells have been proposed to survey surfaces of antigen-presenting cells (APC) or facilitate adhesion under flow; however, whether they serve essential functions during T cell activation remains unclear. Here we show that antigen-specific T cells deposit membrane particles derived from microvilli onto the surface of cognate antigen-bearing APCs. Microvilli carry T cell receptors (TCR) at all stages of T cell activation and are released as large TCR-enriched, T cell microvilli particles (TMP) in a process of trogocytosis.

View Article and Find Full Text PDF

Amelogenin (AMELX) is the main component of the developing tooth enamel matrix and is essential for enamel thickness and structure. However, little is known about its transcriptional regulation. Using gene expression analysis, we found that MIZ-1, a potent transcriptional activator of , is expressed during odontoblastic differentiation of hDPSCs (human dental pulp stem cells), and is essential for odontoblast differentiation and mineralization.

View Article and Find Full Text PDF

Expression of the POK family protein ZNF509L, and -its S1 isoform, is induced by p53 upon exposure to genotoxic stress. Due to alternative splicing of the ZNF509 primary transcript, ZNF509S1 lacks the 6 zinc-fingers and C-terminus of ZNF509L, resulting in only one zinc-finger. ZNF509L and -S1 inhibit cell proliferation by activating p21/CDKN1A and RB transcription, respectively.

View Article and Find Full Text PDF

Kr-POK (ZBTB7c) is a kidney cancer-related POK transcription factor that not only represses transcription of CDKN1A but also increases expression of FASN. However, precisely how Kr-POK affects cell metabolism by controlling gene expression in response to an energy source in rapidly proliferating cells remains unknown. In this study, we characterized the molecular and functional features of Kr-POK in the context of tumor growth and glutamine metabolism.

View Article and Find Full Text PDF

Matrix metalloproteinases (MMPs) are zinc-containing endopeptidases that play roles in cell proliferation, migration, differentiation, angiogenesis, and apoptosis. The expression of MMP gene is tightly regulated and shows cell- and tissue-specific expression patterns. Despite their differential expression, MMP genes have AP-1 (activator protein-1) binding elements within their promoters.

View Article and Find Full Text PDF

KAISO, a member of the POK protein family, is induced by DNA-damaging agents to enhance apoptosis in a p53-dependent manner. Previously, we found that p53 interacts with KAISO, and acetylation of p53 lysine residues by p300 is modulated by KAISO. APAF1, the core molecule of the apoptosome, is transcriptionally activated by KAISO only in cells expressing p53, which binds to APAF1 promoter p53-response elements (p53REs).

View Article and Find Full Text PDF

The NF-κB is found in almost all animal cell types and is involved in a myriad of cellular responses. Aberrant expression of NF-κB has been linked to cancer, inflammatory diseases and improper development. Little is known about transcriptional regulation of the NF-κB family member gene RelA/p65.

View Article and Find Full Text PDF

An unresolved issue in genotoxic stress response is identification of induced regulatory proteins and how these activate tumor suppressor p53 to determine appropriate cell responses. Transcription factor KAISO was previously described to repress transcription following binding to methylated DNA. In this study, we show that KAISO is induced by DNA damage in p53-expressing cells and then interacts with the p53-p300 complex to increase acetylation of p53 K320 and K382 residues, although decreasing K381 acetylation.

View Article and Find Full Text PDF

ZNF509 is unique among POK family proteins in that four isoforms are generated by alternative splicing. Short ZNF509 (ZNF509S1, -S2 and -S3) isoforms contain one or two out of the seven zinc-fingers contained in long ZNF509 (ZNF509L). Here, we investigated the functions of ZNF509 isoforms in response to DNA damage, showing isoforms to be induced by p53.

View Article and Find Full Text PDF

Promyelocytic leukemia zinc finger (PLZF) is a transcription repressor that was initially isolated as a fusion protein with retinoic acid receptor α. PLZF is aberrantly overexpressed in various human solid tumors, such as clear cell renal carcinoma, glioblastoma, and seminoma. PLZF causes cellular transformation of NIH3T3 cells and increases cell proliferation in several cell types.

View Article and Find Full Text PDF

The epithelial-mesenchymal transition (EMT) is a pivotal cellular process during which epithelial polarized cells become motile mesenchymal-appearing cells, which, in turn, promotes the metastatic potential of cancer. Ginseng is a perennial plant belonging to the genus Panax that exhibits a wide range of pharmacological and physiological activities. Ginsenosides 20-Rg3, which is the active component of ginseng, has various medical effects, such as anti-tumorigenic, anti-angiogenesis, and anti-fatiguing activities.

View Article and Find Full Text PDF

HKR3 (Human Krüppel-related 3) is a novel POK (POZ-domain Krüppel-like zinc-finger) family transcription factor. Recently, some of the POK (POZ-domain Krüppel-like zinc finger) family proteins have been shown to play roles in cell cycle arrest, apoptosis, cell proliferation, and oncogenesis. We investigated whether HKR3, an inhibitor of cell proliferation and an uncharacterized POK family protein, could regulate the cell cycle by controlling expression of genes within the p53 pathway (ARF-MDM2-TP53-p21WAF/CDKN1A).

View Article and Find Full Text PDF