1.Establishing a Cre/loxP-based genetic manipulation system for Acanthamoeba: Targeted genome editing and stable reporter expression
Ja Moon AUNG ; So-Young JOO ; Byoung-Kuk NA ; Seunghyeok BANG ; Minsang SHIN ; Youn-Kyoung GOO ; Yeonchul HONG
Parasites, Hosts and Diseases 2025;63(1):25-36
Acanthamoeba is an opportunistic pathogen responsible for granulomatous amoebic encephalitis and amoebic keratitis. Despite its clinical significance, effective treatments remain challenging due to a limited understanding of its pathogenic mechanism. This study developed a genetic manipulation system in Acanthamoeba to facilitate gene function and drug screening studies. We applied the Cre/loxP system to integrate the gene encoding the tdTomato fluorescent protein into the genome of Acanthamoeba castellanii via homologous recombination. The polyubiquitin gene and its untranslated regions were identified and verified, after which the tdTomato gene was cloned between the untranslated regions of the polyubiquitin gene. The construct was then introduced into the Acanthamoeba genome using a modified pLPBLP vector containing loxP sites. Cre recombinase was utilized to remove the neomycin resistance cassette flanked by loxP sites, and genetically modified cells were selected by clonal dilution. The integration of the tdTomato gene, confirmed through PCR and fluorescence microscopy, showed stable expression in both trophozoites and cysts without the need for antibiotic selection. We demonstrated the feasibility of antibiotic-free reporter gene expression in Acanthamoeba. The system provides a valuable tool for functional genomics, allowing us to explore gene functions in Acanthamoeba and develop reliable drug screening models. Furthermore, the ability to express genes without the continuous use of selection markers opens up new possibilities for studying the pathobiology of this pathogen and advancing the development of novel therapeutic strategies against Acanthamoeba infections.
2.Establishing a Cre/loxP-based genetic manipulation system for Acanthamoeba: Targeted genome editing and stable reporter expression
Ja Moon AUNG ; So-Young JOO ; Byoung-Kuk NA ; Seunghyeok BANG ; Minsang SHIN ; Youn-Kyoung GOO ; Yeonchul HONG
Parasites, Hosts and Diseases 2025;63(1):25-36
Acanthamoeba is an opportunistic pathogen responsible for granulomatous amoebic encephalitis and amoebic keratitis. Despite its clinical significance, effective treatments remain challenging due to a limited understanding of its pathogenic mechanism. This study developed a genetic manipulation system in Acanthamoeba to facilitate gene function and drug screening studies. We applied the Cre/loxP system to integrate the gene encoding the tdTomato fluorescent protein into the genome of Acanthamoeba castellanii via homologous recombination. The polyubiquitin gene and its untranslated regions were identified and verified, after which the tdTomato gene was cloned between the untranslated regions of the polyubiquitin gene. The construct was then introduced into the Acanthamoeba genome using a modified pLPBLP vector containing loxP sites. Cre recombinase was utilized to remove the neomycin resistance cassette flanked by loxP sites, and genetically modified cells were selected by clonal dilution. The integration of the tdTomato gene, confirmed through PCR and fluorescence microscopy, showed stable expression in both trophozoites and cysts without the need for antibiotic selection. We demonstrated the feasibility of antibiotic-free reporter gene expression in Acanthamoeba. The system provides a valuable tool for functional genomics, allowing us to explore gene functions in Acanthamoeba and develop reliable drug screening models. Furthermore, the ability to express genes without the continuous use of selection markers opens up new possibilities for studying the pathobiology of this pathogen and advancing the development of novel therapeutic strategies against Acanthamoeba infections.
3.Establishing a Cre/loxP-based genetic manipulation system for Acanthamoeba: Targeted genome editing and stable reporter expression
Ja Moon AUNG ; So-Young JOO ; Byoung-Kuk NA ; Seunghyeok BANG ; Minsang SHIN ; Youn-Kyoung GOO ; Yeonchul HONG
Parasites, Hosts and Diseases 2025;63(1):25-36
Acanthamoeba is an opportunistic pathogen responsible for granulomatous amoebic encephalitis and amoebic keratitis. Despite its clinical significance, effective treatments remain challenging due to a limited understanding of its pathogenic mechanism. This study developed a genetic manipulation system in Acanthamoeba to facilitate gene function and drug screening studies. We applied the Cre/loxP system to integrate the gene encoding the tdTomato fluorescent protein into the genome of Acanthamoeba castellanii via homologous recombination. The polyubiquitin gene and its untranslated regions were identified and verified, after which the tdTomato gene was cloned between the untranslated regions of the polyubiquitin gene. The construct was then introduced into the Acanthamoeba genome using a modified pLPBLP vector containing loxP sites. Cre recombinase was utilized to remove the neomycin resistance cassette flanked by loxP sites, and genetically modified cells were selected by clonal dilution. The integration of the tdTomato gene, confirmed through PCR and fluorescence microscopy, showed stable expression in both trophozoites and cysts without the need for antibiotic selection. We demonstrated the feasibility of antibiotic-free reporter gene expression in Acanthamoeba. The system provides a valuable tool for functional genomics, allowing us to explore gene functions in Acanthamoeba and develop reliable drug screening models. Furthermore, the ability to express genes without the continuous use of selection markers opens up new possibilities for studying the pathobiology of this pathogen and advancing the development of novel therapeutic strategies against Acanthamoeba infections.
4.Establishing a Cre/loxP-based genetic manipulation system for Acanthamoeba: Targeted genome editing and stable reporter expression
Ja Moon AUNG ; So-Young JOO ; Byoung-Kuk NA ; Seunghyeok BANG ; Minsang SHIN ; Youn-Kyoung GOO ; Yeonchul HONG
Parasites, Hosts and Diseases 2025;63(1):25-36
Acanthamoeba is an opportunistic pathogen responsible for granulomatous amoebic encephalitis and amoebic keratitis. Despite its clinical significance, effective treatments remain challenging due to a limited understanding of its pathogenic mechanism. This study developed a genetic manipulation system in Acanthamoeba to facilitate gene function and drug screening studies. We applied the Cre/loxP system to integrate the gene encoding the tdTomato fluorescent protein into the genome of Acanthamoeba castellanii via homologous recombination. The polyubiquitin gene and its untranslated regions were identified and verified, after which the tdTomato gene was cloned between the untranslated regions of the polyubiquitin gene. The construct was then introduced into the Acanthamoeba genome using a modified pLPBLP vector containing loxP sites. Cre recombinase was utilized to remove the neomycin resistance cassette flanked by loxP sites, and genetically modified cells were selected by clonal dilution. The integration of the tdTomato gene, confirmed through PCR and fluorescence microscopy, showed stable expression in both trophozoites and cysts without the need for antibiotic selection. We demonstrated the feasibility of antibiotic-free reporter gene expression in Acanthamoeba. The system provides a valuable tool for functional genomics, allowing us to explore gene functions in Acanthamoeba and develop reliable drug screening models. Furthermore, the ability to express genes without the continuous use of selection markers opens up new possibilities for studying the pathobiology of this pathogen and advancing the development of novel therapeutic strategies against Acanthamoeba infections.
5.Establishing a Cre/loxP-based genetic manipulation system for Acanthamoeba: Targeted genome editing and stable reporter expression
Ja Moon AUNG ; So-Young JOO ; Byoung-Kuk NA ; Seunghyeok BANG ; Minsang SHIN ; Youn-Kyoung GOO ; Yeonchul HONG
Parasites, Hosts and Diseases 2025;63(1):25-36
Acanthamoeba is an opportunistic pathogen responsible for granulomatous amoebic encephalitis and amoebic keratitis. Despite its clinical significance, effective treatments remain challenging due to a limited understanding of its pathogenic mechanism. This study developed a genetic manipulation system in Acanthamoeba to facilitate gene function and drug screening studies. We applied the Cre/loxP system to integrate the gene encoding the tdTomato fluorescent protein into the genome of Acanthamoeba castellanii via homologous recombination. The polyubiquitin gene and its untranslated regions were identified and verified, after which the tdTomato gene was cloned between the untranslated regions of the polyubiquitin gene. The construct was then introduced into the Acanthamoeba genome using a modified pLPBLP vector containing loxP sites. Cre recombinase was utilized to remove the neomycin resistance cassette flanked by loxP sites, and genetically modified cells were selected by clonal dilution. The integration of the tdTomato gene, confirmed through PCR and fluorescence microscopy, showed stable expression in both trophozoites and cysts without the need for antibiotic selection. We demonstrated the feasibility of antibiotic-free reporter gene expression in Acanthamoeba. The system provides a valuable tool for functional genomics, allowing us to explore gene functions in Acanthamoeba and develop reliable drug screening models. Furthermore, the ability to express genes without the continuous use of selection markers opens up new possibilities for studying the pathobiology of this pathogen and advancing the development of novel therapeutic strategies against Acanthamoeba infections.
6.TP53 Mutation Status in Myelodysplastic Neoplasm and Acute Myeloid Leukemia: Impact of Reclassification Based on the 5th WHO and International Consensus Classification Criteria: A Korean Multicenter Study
Hyun-Young KIM ; Saeam SHIN ; Jong-Mi LEE ; In-Suk KIM ; Boram KIM ; Hee-Jin KIM ; Yu Jeong CHOI ; Byunggyu BAE ; Yonggoo KIM ; Eunhui JI ; Hyerin KIM ; Hyerim KIM ; Jee-Soo LEE ; Yoon Hwan CHANG ; Hyun Kyung KIM ; Ja Young LEE ; Shinae YU ; Miyoung KIM ; Young-Uk CHO ; Seongsoo JANG ; Myungshin KIM
Annals of Laboratory Medicine 2025;45(2):160-169
Background:
TP53 mutations are associated with poor prognosis in myelodysplastic neoplasm (MDS) and AML. The updated 5th WHO classification and International Consensus Classification (ICC) categorize TP53-mutated MDS and AML as unique entities. We conducted a multicenter study in Korea to investigate the characteristics of TP53-mutated MDS and AML, focusing on diagnostic aspects based on updated classifications.
Methods:
This study included patients aged ≥ 18 yrs who were diagnosed as having MDS(N = 1,244) or AML (N = 2,115) at six institutions. The results of bone marrow examination, cytogenetic studies, and targeted next-generation sequencing, including TP53, were collected and analyzed.
Results:
TP53 mutations were detected in 9.3% and 9.2% of patients with MDS and AML, respectively. Missense mutation was the most common, with hotspot codons R248/ R273/G245/Y220/R175/C238 accounting for 25.4% of TP53 mutations. Ten percent of patients had multiple TP53 mutations, and 78.4% had a complex karyotype. The median variant allele frequency (VAF) of TP53 mutations was 41.5%, with a notable difference according to the presence of a complex karyotype. According to the 5th WHO classification and ICC, the multi-hit TP53 mutation criteria were met in 58.6% and 75% of MDS patients, respectively, and the primary determinants were a TP53 VAF > 50% for the 5th WHO classification and the presence of a complex karyotype for the ICC.
Conclusions
Collectively, we elucidated the molecular genetic characteristics of patients with TP53-mutated MDS and AML, highlighting key factors in applying TP53 mutation-related criteria in updated classifications, which will aid in establishing diagnostic strategies.
7.Cancer Patients' and Caregivers' Experiences Admitted to Comprehensive Nursing Care Service Wards: An Exploratory Qualitative Research
Sarah LIM ; Mee Young CHO ; Hyun Joo SHIN ; Ki Yeon SONG ; Soo Kyoung SHIM ; Yoon Jung LEE ; Hea Jin KWON ; Ji Eun KIM ; Hui Ean KIM ; Hyun Ja PARK ; Han Wool AN ; So Jeong HYEON ; Sue KIM
Asian Oncology Nursing 2024;24(4):173-183
Purpose:
The purpose of this study was to explore and assess the experiences of cancer patients and their caregivers who had been admitted to comprehensive nursing care service wards.
Methods:
Data were collected from 10 patients and 10 caregivers by in-depth interviews. The data were analyzed using content analysis of Downe-Wamboldt.
Results:
Three categories and seven subcategories were extracted. 1) Realizing institutional limitations of comprehensive nursing care service: ‘Wishing for precise operating systems based on patient severity,’ ‘Anticipating active caregiver participation in treatment process,’ ‘Requiring a countermeasure for safety accidents,’ 2) Professional nursing service which provides relief: ‘Patient-centered professional nursing service,’ ‘Inpatient service that provides relief for patients and caregivers,’ 3) Anticipating continuous use of the service: ‘Inpatient service which users are willing to reuse,’ ‘Wishing for expansion and reinforcement of the service.’
Conclusion
Cancer patients and their caregivers experienced institutional limitations while satisfied with professional nursing service and willing to reuse the service. To improve this situation, institutional support such as separate wards for severe patients, measures for active caregiver participation and prevention of safety accidents, and adequate staffing would be helpful for relatively severe level cancer patients and their caregivers.
8.IFITM3-mediated activation of TRAF6/MAPK/AP-1pathways induces acquired TKI resistance in clear cell renal cell carcinoma
Se Un JEONG ; Ja-Min PARK ; Sun Young YOON ; Hee Sang HWANG ; Heounjeong GO ; Dong-Myung SHIN ; Hyein JU ; Chang Ohk SUNG ; Jae-Lyun LEE ; Gowun JEONG ; Yong Mee CHO
Investigative and Clinical Urology 2024;65(1):84-93
Purpose:
Vascular endothelial growth factor tyrosine kinase inhibitors (TKIs) have been the standard of care for advanced and metastatic clear cell renal cell carcinoma (ccRCC). However, the therapeutic effect of TKI monotherapy remains unsatisfactory given the high rates of acquired resistance to TKI therapy despite favorable initial tumor response.
Materials and Methods:
To define the TKI-resistance mechanism and identify new therapeutic target for TKI-resistant ccRCC, an integrative differential gene expression analysis was performed using acquired resistant cohort and a public dataset. Sunitinib-resistant RCC cell lines were established and used to test their malignant behaviors of TKI resistance through in vitro and in vivo studies. Immunohistochemistry was conducted to compare expression between the tumor and normal kidney and verify expression of pathway-related proteins.
Results:
Integrated differential gene expression analysis revealed increased interferon-induced transmembrane protein 3 (IFITM3) expression in post-TKI samples. IFITM3 expression was increased in ccRCC compared with the normal kidney. TKI-resistant RCC cells showed high expression of IFITM3 compared with TKI-sensitive cells and displayed aggressive biologic features such as higher proliferative ability, clonogenic survival, migration, and invasion while being treated with sunitinib. These aggressive features were suppressed by the inhibition of IFITM3 expression and promoted by IFITM3 overexpression, and these findings were confirmed in a xenograft model. IFITM3-mediated TKI resistance was associated with the activation of TRAF6 and MAPK/AP-1 pathways.
Conclusions
These results demonstrate IFITM3-mediated activation of the TRAF6/MAPK/AP-1 pathways as a mechanism of acquired TKI resistance, and suggest IFITM3 as a new target for TKI-resistant ccRCC.
9.Clinical Practice Guideline for Blood-based Circulating Tumor DNA Assays
Jee-Soo LEE ; Eun Hye CHO ; Boram KIM ; Jinyoung HONG ; Young-gon KIM ; Yoonjung KIM ; Ja-Hyun JANG ; Seung-Tae LEE ; Sun-Young KONG ; Woochang LEE ; Saeam SHIN ; Eun Young SONG ;
Annals of Laboratory Medicine 2024;44(3):195-209
Circulating tumor DNA (ctDNA) has emerged as a promising tool for various clinical applications, including early diagnosis, therapeutic target identification, treatment response monitoring, prognosis evaluation, and minimal residual disease detection. Consequently, ctDNA assays have been incorporated into clinical practice. In this review, we offer an indepth exploration of the clinical implementation of ctDNA assays. Notably, we examined existing evidence related to pre-analytical procedures, analytical components in current technologies, and result interpretation and reporting processes. The primary objective of this guidelines is to provide recommendations for the clinical utilization of ctDNA assays.
10.Cancer Patients' and Caregivers' Experiences Admitted to Comprehensive Nursing Care Service Wards: An Exploratory Qualitative Research
Sarah LIM ; Mee Young CHO ; Hyun Joo SHIN ; Ki Yeon SONG ; Soo Kyoung SHIM ; Yoon Jung LEE ; Hea Jin KWON ; Ji Eun KIM ; Hui Ean KIM ; Hyun Ja PARK ; Han Wool AN ; So Jeong HYEON ; Sue KIM
Asian Oncology Nursing 2024;24(4):173-183
Purpose:
The purpose of this study was to explore and assess the experiences of cancer patients and their caregivers who had been admitted to comprehensive nursing care service wards.
Methods:
Data were collected from 10 patients and 10 caregivers by in-depth interviews. The data were analyzed using content analysis of Downe-Wamboldt.
Results:
Three categories and seven subcategories were extracted. 1) Realizing institutional limitations of comprehensive nursing care service: ‘Wishing for precise operating systems based on patient severity,’ ‘Anticipating active caregiver participation in treatment process,’ ‘Requiring a countermeasure for safety accidents,’ 2) Professional nursing service which provides relief: ‘Patient-centered professional nursing service,’ ‘Inpatient service that provides relief for patients and caregivers,’ 3) Anticipating continuous use of the service: ‘Inpatient service which users are willing to reuse,’ ‘Wishing for expansion and reinforcement of the service.’
Conclusion
Cancer patients and their caregivers experienced institutional limitations while satisfied with professional nursing service and willing to reuse the service. To improve this situation, institutional support such as separate wards for severe patients, measures for active caregiver participation and prevention of safety accidents, and adequate staffing would be helpful for relatively severe level cancer patients and their caregivers.

Result Analysis
Print
Save
E-mail