Publications by authors named "KyuKwang Kim"

Ovarian cancer is the leading cause of death among gynecologic malignancies. Despite recent advancements in targeted therapies such as PARP inhibitors, recurrence is common and frequently resistant to existing therapies. A powerful diagnostic tool, coupled with a comprehensive understanding of its implications, is crucial.

View Article and Find Full Text PDF

Circulating Tumor Cells (CTCs) may serve as a non-invasive source of tumor material to investigate an individual's disease in real-time. The Parsortix PC1 System, the first FDA-cleared medical device for the capture and harvest of CTCs from peripheral blood of metastatic breast cancer (MBC) patients for use in subsequent user-validated downstream analyses, enables the epitope-independent capture of CTCs with diverse phenotypes based on cell size and deformability. The aim of this study was to determine the proportion of MBC patients and self-declared female healthy volunteers (HVs) that had CTCs identified using immunofluorescence (IF) or Wright-Giemsa (WG) staining.

View Article and Find Full Text PDF

Forchlorfenuron (FCF) is a widely used plant cytokinin that enhances fruit quality and size in agriculture. It also serves as a crucial pharmacological tool for the inhibition of septins. However, the precise target of FCF has not yet been fully determined.

View Article and Find Full Text PDF

Introduction: The Parsortix PC1 system, Food and Drug Administration (FDA) cleared for use in metastatic breast cancer (MBC) patients, is an epitope-independent microfluidic device for the capture and harvest of circulating tumor cells from whole blood based on cell size and deformability. This report details the analytical characterization of linearity, detection limit, precision, and reproducibility for this device.

Methods: System performance was determined using K-EDTA blood samples collected from self-declared healthy female volunteers (HVs) and MBC patients spiked with prelabeled cultured breast cancer cell lines (SKBR3, MCF7, or Hs578T).

View Article and Find Full Text PDF

The regulatory effect of non-coding large-scale structural variations (SVs) on proto-oncogene activation remains unclear. This study investigated SV-mediated gene dysregulation by profiling 3D cancer genome maps from 40 patients with colorectal cancer (CRC). We developed a machine learning-based method for spatial characterization of the altered 3D cancer genome.

View Article and Find Full Text PDF

Inter-chromosomal interactions play a crucial role in genome organization, yet the organizational principles remain elusive. Here, we introduce a novel computational method to systematically characterize inter-chromosomal interactions using in situ Hi-C results from various cell types. Our method successfully identifies two apparently hub-like inter-chromosomal contacts associated with nuclear speckles and nucleoli, respectively.

View Article and Find Full Text PDF

Genetic differences inferred from sequencing reads can be used for demultiplexing of pooled single-cell RNA-seq (scRNA-seq) data across multiple donors without WGS-based reference genotypes. However, such methods could not be directly applied to single-cell ATAC-seq (scATAC-seq) data owing to the lower read coverage for each variant compared to scRNA-seq. We propose a new software, scATAC-seq Variant-based EstimatioN for GEnotype ReSolving (scAVENGERS), which resolves this issue by calling more individual-specific germline variants and using an optimized mixture model for the scATAC-seq.

View Article and Find Full Text PDF

Hi-C and capture Hi-C have greatly advanced our understanding of the principles of higher-order chromatin structure. In line with the evolution of the Hi-C protocols, there is a demand for an advanced computational method that can be applied to the various forms of Hi-C protocols and effectively remove innate biases. To resolve this issue, we developed an implicit normalization method named "covNorm" and implemented it as an R package.

View Article and Find Full Text PDF

The mammalian genome is highly packed into the nucleus. Over the past decade, the development of Hi-C has contributed significantly to our understanding of the three-dimensional (3D) chromatin structure, uncovering the principles and functions of higher-order chromatin organizations. Recent studies have repositioned its property in spatial proximity measurement to address challenging problems in genome analyses including genome assembly, haplotype phasing, and the detection of genomic rearrangements.

View Article and Find Full Text PDF

Three-dimensional (3D) genome organization is tightly coupled with gene regulation in various biological processes and diseases. In cancer, various types of large-scale genomic rearrangements can disrupt the 3D genome, leading to oncogenic gene expression. However, unraveling the pathogenicity of the 3D cancer genome remains a challenge since closer examinations have been greatly limited due to the lack of appropriate tools specialized for disorganized higher-order chromatin structure.

View Article and Find Full Text PDF

Chromosomes located in the nucleus form discrete units of genetic material composed of DNA and protein complexes. The genetic information is encoded in linear DNA sequences, but its interpretation requires an understanding of threedimensional (3D) structure of the chromosome, in which distant DNA sequences can be juxtaposed by highly condensed chromatin packing in the space of nucleus to precisely control gene expression. Recent technological innovations in exploring higher-order chromatin structure have uncovered organizational principles of the 3D genome and its various biological implications.

View Article and Find Full Text PDF

Mosquito control is important as mosquitoes are extremely harmful pests that spread various infectious diseases. In this research, we present the preliminary results of an automated system that detects the presence of mosquitoes via image processing using multiple deep learning networks. The Fully Convolutional Network (FCN) and neural network-based regression demonstrated an accuracy of 84%.

View Article and Find Full Text PDF
Article Synopsis
  • Epithelial Ovarian Cancer (EOC) has low survival rates because patients are often diagnosed late and resist standard treatments, highlighting the need for new therapies.
  • Septin-2, a GTP binding protein, has been identified for the first time in EOC and shows overexpression in certain cancerous tissues compared to non-cancerous ones.
  • Knocking down septin-2 in ovarian cancer cells reduced their growth and revealed changes in crucial metabolic pathways, indicating that septin-2 could significantly influence cancer development through its impact on protein modifications and metabolism.
View Article and Find Full Text PDF
Article Synopsis
  • The study investigates Human epididymis secretory protein 4 (HE4) and its role in immune evasion in ovarian cancer, highlighting its selective overexpression as a biomarker for tumorigenesis.
  • Researchers found that HE4 significantly upregulates the gene Dual specificity phosphatase 6 (DUSP6) in immune cells, specifically CD8 and CD56 cells, which leads to reduced phosphorylation of Erk1/2, impacting immune response.
  • The results showed that HE4 increases cancer cell proliferation by impairing the function of critical immune cells, an effect that can be partially reversed using a DUSP6 inhibitor, indicating a potential pathway for therapeutic intervention.
View Article and Find Full Text PDF

Here, MineLoC is described as a pipeline developed to generate 3D printable models of master templates for Lab-on-a-Chip (LoC) by using a popular multi-player sandbox game “Minecraft”. The user can draw a simple diagram describing the channels and chambers of the Lab-on-a-Chip devices with pre-registered color codes which indicate the height of the generated structure. MineLoC converts the diagram into large chunks of blocks (equal sized cube units composing every object in the game) in the game world.

View Article and Find Full Text PDF

Microfluidic devices are an emerging platform for a variety of experiments involving bacterial cell culture, and has advantages including cost and convenience. One inevitable step during bacterial cell culture is the measurement of cell concentration in the channel. The optical density measurement technique is generally used for bacterial growth estimation, but it is not applicable to microfluidic devices due to the small sample volumes in microfluidics.

View Article and Find Full Text PDF

Simple methods using the striped pattern paper marker and FFT (fast Fourier transformation) have been proposed as alternatives to measuring the optical density for determining the level of bacterial growth. The marker-based method can be easily automated, but due to image-processing-base of the method, the presence of light or the color of the culture broth can disturb the detection process. This paper proposes a modified version of marker-FFT-based growth detection that uses a light emitting diode (LED) array as a marker.

View Article and Find Full Text PDF

The detection of bacterial growth in liquid media is an essential process in determining antibiotic susceptibility or the level of bacterial presence for clinical or research purposes. We have developed a system, which enables simplified and automated detection using a camera and a striped pattern marker. The quantification of bacterial growth is possible as the bacterial growth in the culturing vessel blurs the marker image, which is placed on the back of the vessel, and the blurring results in a decrease in the high-frequency spectrum region of the marker image.

View Article and Find Full Text PDF

In this research an open source, low power sensor node was developed to check the growth of mycobacteria in a culture bottle with a nitrate reductase assay method for a drug susceptibility test. The sensor system reports the temperature and color sensor output frequency change of the culture bottle when the device is triggered. After the culture process is finished, a nitrite ion detecting solution based on a commercial nitrite ion detection kit is injected into the culture bottle by a syringe pump to check bacterial growth by the formation of a pigment by the reaction between the solution and the color sensor.

View Article and Find Full Text PDF

A sensor node for sampling water and checking for the presence of harmful bacteria such as E. coli in water sources was developed in this research. A chromogenic enzyme substrate assay method was used to easily detect coliform bacteria by monitoring the color change of the sampled water mixed with a reagent.

View Article and Find Full Text PDF

Antiestrogens including tamoxifen and fulvestrant have been evaluated as chemotherapeutics for ovarian cancer, particularly in cases of platinum resistant disease. Human epididymis protein 4 (HE4) is highly overexpressed in women with ovarian cancer and overexpression of HE4 has been found to correlate with platinum resistance. However, the role of HE4 in modulating responses to hormones and hormonal therapy has not been characterized in ovarian cancer.

View Article and Find Full Text PDF

Selective overexpression of Human epididymal secretory protein E4 (HE4) points to a role in ovarian cancer tumorigenesis but little is known about the role the HE4 gene or the gene product plays. Here we show that elevated HE4 serum levels correlate with chemoresistance and decreased survival rates in EOC patients. HE4 overexpression promoted xenograft tumor growth and chemoresistance against cisplatin in an animal model resulting in reduced survival rates.

View Article and Find Full Text PDF

Objective: Chemotherapy options for advanced endometrial cancer are limited and newer therapeutic agents are urgently needed. This study describes the therapeutic potential of 7 Methyl-indole ethyl isothiocyanate (7Me-IEITC) in endometrial cancer cell lines.

Methods: 7Me-IEITC was synthesized in our laboratory.

View Article and Find Full Text PDF

Medulloblastoma, a neuroectodermal tumor arising in the cerebellum, is the most common brain tumor found in children. We recently showed that nifurtimox induces production of reactive oxygen species (ROS) and subsequent apoptosis in neuroblastoma cells both in vitro and in vivo. Tetrathiomolybdate (TM) has been shown to decrease cell proliferation by inhibition of superoxide dismutase-1 (SOD1).

View Article and Find Full Text PDF