1.KEAP1-NRF2 Pathway as a Novel Therapeutic Target for EGFR-Mutant Non-small Cell Lung Cancer
Jae-Sun CHOI ; Hye-Min KANG ; Kiyong NA ; Jiwon KIM ; Tae-Woo KIM ; Junyang JUNG ; Heejin LIM ; Hyewon SEO ; Seung Hyeun LEE
Tuberculosis and Respiratory Diseases 2025;88(1):138-149
Background:
Kelch-like ECH-associated protein 1 (KEAP1)–nuclear factor erythroid- 2-related factor 2 (NRF2) pathway is a major regulator protecting cells from oxidative and metabolic stress. Studies have revealed that this pathway is involved in mediating resistance to cytotoxic chemotherapy and immunotherapy; however, its implications in oncogene-addicted tumors are largely unknown. This study aimed to elucidate whether this pathway could be a potential therapeutic target for epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer.
Methods:
We measured the baseline expression of NRF2 using EGFR-mutant parental cells and acquired gefitinib resistant cells. We investigated whether NRF2 inhibition affected cell death in vitro and tumor growth in vivo using a xenograft mouse model, and compared the transcriptional changes before and after NRF2 inhibition.
Results:
Baseline NRF2 expression was enhanced in PC9 and PC9 with gefitinib resistance (PC9/GR) cells than in other cell lines, with a more prominent expression in PC9/ GR. The NRF2 inhibitor induced NRF2 downregulation and cell death in a dose-dependent manner. Cotreatment with an NRF2 inhibitor enhanced osimertinib-induced cell death in vitro, and potentiated tumor growth inhibition in a PC9/GR xenograft model. Finally, RNA sequencing revealed that NRF2 inhibition resulted in the altered expression of multiple genes involved in various signaling pathways.
Conclusion
We identified that NRF2 inhibition enhanced cell death and inhibited tumor growth in tyrosine kinase inhibitor (TKI)-resistant lung cancer with EGFR-mutation. Thus, NRF2 modulation may be a novel therapeutic strategy to overcome the resistance to EGFR-TKIs.
2.Conventional versus Instillation Negative-Pressure Wound Therapy for Severe Soft Tissue Injury in Open Pelvic Fractures: A Retrospective Review
Donghwan CHOI ; Won Tae CHO ; Hyung Keun SONG ; Junsik KWON ; Byung Hee KANG ; Hohyung JUNG ; Min Ji KIM ; Kyoungwon JUNG
Yonsei Medical Journal 2025;66(2):94-102
Purpose:
We investigated the clinical features, current negative-pressure wound therapy (NPWT) management strategies, and outcomes of pelvic-perineal soft tissue infection after open pelvic fractures.
Materials and Methods:
We analyzed the data of patients admitted to our trauma center with pelvic-perineal soft tissue after open pelvic fractures over a 7-year period. We investigated the injury severity score (ISS), medical costs, number of NPWTs, time required to reach definite wound coverage, complications, fracture classifications, transfusion requirements, interventions, length of stay (LOS) in hospital and intensive care unit (ICU), and prognosis.
Results:
Twenty patients with open pelvic fractures were treated with NPWT, and one patient who underwent NPWT died of pelvic sepsis during ICU treatment. The median LOS in hospital and medical costs were 98 [56–164] days and 106400 [65600–171100] USD, respectively. Patients treated with instillation NPWT (iNPWT, n=10) had a shorter NPWT duration (24 [13–39] vs. 46 [42–91] days, p=0.023), time to definite wound coverage (30 [21–43] vs. 49 [42–93] days, p=0.026), and hospital LOS (56 [43–72] vs. 158 [101–192] days, p=0.001), as well as lower medical costs (67800 [42500–102500] vs. 144200 [110400–236000] USD, p=0.009) compared to those treated with conventional NPWT.
Conclusion
NPWT is a feasible method for treating pelvic soft tissue infections in patients with open pelvic fractures. iNPWT can reduce the duration of NPWT, hospital LOS, and medical costs.
3.Differences in Treatment Outcomes Depending on the Adjuvant Treatment Modality in Craniopharyngioma
Byung Min LEE ; Jaeho CHO ; Dong-Seok KIM ; Jong Hee CHANG ; Seok-Gu KANG ; Eui-Hyun KIM ; Ju Hyung MOON ; Sung Soo AHN ; Yae Won PARK ; Chang-Ok SUH ; Hong In YOON
Yonsei Medical Journal 2025;66(3):141-150
Purpose:
Adjuvant treatment for craniopharyngioma after surgery is controversial. Adjuvant external beam radiation therapy (EBRT) can increase the risk of long-term sequelae. Stereotactic radiosurgery (SRS) is used to reduce treatment-related toxicity.In this study, we compared the treatment outcomes and toxicities of adjuvant therapies for craniopharyngioma.
Materials and Methods:
We analyzed patients who underwent craniopharyngioma tumor removal between 2000 and 2017. Of the 153 patients, 27 and 20 received adjuvant fractionated EBRT and SRS, respectively. We compared the local control (LC), progression-free survival (PFS), and overall survival between groups that received adjuvant fractionated EBRT, SRS, and surveillance.
Results:
The median follow-up period was 77.7 months. For SRS and surveillance, the 10-year LC was 57.2% and 57.4%, respectively. No local progression was observed after adjuvant fractionated EBRT. One patient in the adjuvant fractionated EBRT group died owing to glioma 94 months after receiving radiotherapy (10-year PFS: 80%). The 10-year PFS was 43.6% and 50.7% in the SRS and surveillance groups, respectively. The treatment outcomes significantly differed according to adjuvant treatment in nongross total resection (GTR) patients. Additional treatment-related toxicity was comparable in the adjuvant fractionated EBRT and other groups.
Conclusion
Adjuvant fractionated EBRT could be effective in controlling local failure, especially in patients with non-GTR, while maintaining acceptable treatment-related toxicity.
4.Long-Term Incidence of Gastrointestinal Bleeding Following Ischemic Stroke
Jun Yup KIM ; Beom Joon KIM ; Jihoon KANG ; Do Yeon KIM ; Moon-Ku HAN ; Seong-Eun KIM ; Heeyoung LEE ; Jong-Moo PARK ; Kyusik KANG ; Soo Joo LEE ; Jae Guk KIM ; Jae-Kwan CHA ; Dae-Hyun KIM ; Tai Hwan PARK ; Kyungbok LEE ; Hong-Kyun PARK ; Yong-Jin CHO ; Keun-Sik HONG ; Kang-Ho CHOI ; Joon-Tae KIM ; Dong-Eog KIM ; Jay Chol CHOI ; Mi-Sun OH ; Kyung-Ho YU ; Byung-Chul LEE ; Kwang-Yeol PARK ; Ji Sung LEE ; Sujung JANG ; Jae Eun CHAE ; Juneyoung LEE ; Min-Surk KYE ; Philip B. GORELICK ; Hee-Joon BAE ;
Journal of Stroke 2025;27(1):102-112
Background:
and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes.
Methods:
We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data.
Results:
Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2 , and a 3-month modified Rankin Scale score of ≥4.
Conclusion
Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.
5.Digital therapeutics in Korea: current status, challenges, and future directions – a narrative review
Hee Jun SHIN ; Ik Tae CHO ; Wan Suk CHOI ; Hong Rae KIM ; Min Bong KANG ; Won Jong YANG
Journal of Yeungnam Medical Science 2025;42(1):8-
Digital therapeutics (DTx) are emerging as a transformative innovation in healthcare offering evidence-based digital interventions for the treatment, management, and prevention of various diseases and disorders. In Korea, DTx have gained significant attention as potential solutions to the increasing burden of chronic diseases and mental health conditions. However, the Korean DTx market faces several challenges that hinder its widespread adoption and integration into the national healthcare system. This study provides a comprehensive analysis of the current state of the DTx market in Korea, identifies the key challenges impeding its growth, and proposes strategies for overcoming these obstacles. This study utilized a literature review and market analysis approach to examine the latest research, industry reports, and regulatory documents related to DTx. The analysis focused on three primary areas: (1) the current regulatory landscape, (2) technological advancements and challenges, and (3) economic and commercial factors influencing DTx adoption in Korea. A comparative analysis of global regulatory practices was also conducted to identify best practices. The findings revealed that while Korea has made significant strides in supporting DTx development, the market remains in its early stages. The key challenges include underdeveloped regulatory frameworks, issues with data quality and security, and a lack of established reimbursement pathways. We recommend developing tailored regulatory frameworks for DTx, enhancing policy support for small and medium-sized enterprises involved in DTx development, and increasing investments in technological infrastructure. By addressing these challenges, Korea could position itself as a leader in the global DTx market, delivering innovative and effective treatments to enhance patient care and outcomes.
6.Safety and Efficacy of Pivot-Balloon for Severe Tricuspid Regurgitation:The First-in-Man Experiences
Eun Kyoung KIM ; Min-Ku CHON ; Hyun-Sook KIM ; Yong-Hyun PARK ; Sang-Hyun LEE ; Ki Seok CHOO ; Hyung Gon JE ; Dae-Hee KIM ; Tae Oh KIM ; Yoon Seok KOH ; Jae-Hyeong PARK ; Jae-Hwan LEE ; Young Jin CHOI ; Eun Seok SHIN ; Hyuck-Jun YOON ; Seung-Whan LEE ; Joo-Yong HAHN
Korean Circulation Journal 2025;55(1):20-31
Background and Objectives:
Among various emerging catheter-based treatments for severe tricuspid regurgitation (TR), the spacer device can reduce the regurgitation orifice without manipulating the valve leaflet. However, its clinical application has been hampered by traumatic anchoring to the myocardium and the coaxial alignment of the balloon resulting in insufficient TR reduction. This study aimed to evaluate the early-stage safety, technical feasibility, and preliminary efficacy of the novel atraumatic vertical spacer in patients with isolated severe TR.
Methods:
All procedures were guided by fluoroscopy and transthoracic echocardiography.The maximum device placement time with an inflated balloon was 24 hours. Changes in the amount of TR, right ventricular function, and patient hemodynamics were measured during balloon deployment.
Results:
A total of 7 patients (median age 74), underwent successful device implantation without procedure-related complications. During balloon inflation (median 25 minutes), there were no symptoms or signs indicative of TR intolerance. TR was reduced by 1 grade or greater in all patients, with 2 patients exhibiting a reduction of 3 grades, from torrential TR to a moderate degree. Mild TR after balloon inflation was achieved in 3 patients with baseline severe TR. The TR reduction observed during initial balloon deployment was sustained during the subsequent balloon maintenance period.
Conclusions
The Pivot-balloon procedure was safe, technically feasible, and effective in reducing TR in patients with severe TR. No periprocedural complications or adverse cardiovascular events were reported during device placement with TR reduction observed in all patients. However, longer-term follow-up is needed to confirm safety and treatment effect.
7.Age Estimation Using Attrition and Pulp Cavity Size of the Mandibular First Molar in Korean Population
Hee-Won KIM ; Hye-Mi JEON ; Kyung-Hee KIM ; Hye-Min JU ; Soo-Min OK ; Sung-Hee JEONG ; Yong-Woo AHN
Korean Journal of Legal Medicine 2025;49(1):1-6
In forensic science, age estimation is essential for identifying both living and deceased individuals. Teeth and jawbones serve as reliable indicators due to their gradual age-related changes and resistance to environmental factors. Among the various methods, attrition and pulp cavity size are commonly used to estimate adult age. This study aimed to enhance the accuracy of age estimation in Korean adults by combining measurements of tooth attrition and pulp cavity size obtained from panoramic radiographs of mandibular first molars. We evaluated 118 patients (62 male, 56 female) who visited Pusan National University Dental Hospital between 2010 and 2024. Radiographs and clinical photographs were analyzed for grade C teeth with exposed dentin using Takei’s method, and the pulp chamber height ratio (PCHR) and width ratio (PCWR) were measured using Jeon’s method. Intraobserver reliability was high (intraclass correlation coefficient>0.6), with no significant sex-based differences in PCHR and PCWR. Both ratios negatively correlated with age, with PCWR showing a stronger correlation, particularly in females (r=–0.606). This study derived an improved age estimation formula with R² values ranging from 0.540 to 0.546 when both PCHR and PCWR were combined. Despite the limitations of this study, such as its small sample size and reliance on panoramic radiographs, the findings suggest that combining tooth wear and pulp cavity size offers a more robust tool for age estimation in clinical and forensic settings.
8.Minocycline Susceptibility of Carbapenem-Resistant Acinetobacter baumannii Blood Isolates from a Single Center in Korea: Role of tetB in Resistance
Taeeun KIM ; Eun Hee JEON ; Yoon-Kyoung HONG ; Jiwon JUNG ; Min Jae KIM ; Heungsup SUNG ; Mi-Na KIM ; Sung-Han KIM ; Sang-Ho CHOI ; Sang-Oh LEE ; Yang Soo KIM ; Yong Pil CHONG
Infection and Chemotherapy 2025;57(1):111-118
Background:
Carbapenem-resistant Acinetobacter baumannii (CRAB) represents a devastating and growing global threat, calling for new antibiotic treatments. In Korea, the challenge of treating CRAB is compounded by high nosocomial acquisition rates and limited availability of novel antibiotics. Minocycline, a semisynthetic tetracycline derivative, has been proposed as a therapeutic option for CRAB infections. Nonsusceptibility to minocycline may occur through the efflux pump, TetB. The prevalence of tetB in A. baumannii has increased, along with higher minocycline minimum inhibitory concentrations (MICs). We aimed to evaluate minocycline susceptibility rates in clinical strains of CRAB, and the association between tetB carriage and minocycline susceptibility across different genotypes.
Materials and Methods:
Representative CRAB blood isolates were collected from Asan Medical Center, Seoul.Minocycline susceptibility was assessed using the Clinical and Laboratory Standards Institute (CLSI) breakpoint (≤4 mg/L) and the proposed pharmacokinetics (PK)/pharmacodynamics (PD) breakpoint (≤1 mg/L). Tigecycline was used as a comparator, and its susceptibility breakpoint for Enterobacterales defined by EUCAST was applied (≤0.5 mg/L).The presence of tetB was detected by PCR, and multilocus sequence typing (MLST) was performed using seven housekeeping genes.
Results:
Of the 160 CRAB blood isolates, 83.8% were susceptible to minocycline by the CLSI criteria, and 50.6% were PK-PD susceptible by the PK-PD criteria. The minocycline minimum inhibitory concentration (MIC)50 /MIC90 was 1/8 mg/L. tetB was present in 49% of isolates and was associated with a higher minocycline MIC (MIC50/90 2/8 mg/L vs. 1/2 mg/L). No clear correlation was observed between tetB positivity and tigecycline MIC. Nine MLSTs were identified, with significant differences in tetB carriage rates between the major sequence types. Notably, ST191, associated with non-tetB carriage and greater susceptibility to minocycline, declined over the study period (P=0.004), while ST451, associated with tetB carriage, increased.
Conclusion
tetB was present in 49% of CRAB isolates and was associated with higher MICs and non-susceptibility by both CLSI and PK-PD criteria. However, absence of tetB was not a reliable predictor of minocycline PK-PD susceptibility. Additionally, shifts over time towards genotypes with reduced minocycline susceptibility were observed. Further research is needed to correlate these findings with clinical outcomes and identify additional resistance mechanisms.
9.Update on Medical Management of Acute Peripheral Facial Palsy
Sang Hoon KIM ; Min Young KWAK
Journal of Audiology & Otology 2025;29(1):1-7
Acute facial nerve palsy, particularly Bell’s palsy, is a common neurological disorder with an annual incidence of 20-30 cases per 100,000 individuals. It is characterized by sudden or gradual facial muscle palsy and is caused by viral reactivation, inflammation, or ischemia of the facial nerve. Prognosis varies widely, depending on the severity of nerve damage and timeliness of the intervention. Steroid therapy remains the cornerstone of Bell’s palsy treatment because it reduces inflammation and facilitates recovery. Early administration, preferably within 72 hours of symptom onset, considerably improves outcomes. However, the efficacy of combination therapy remains controversial. Current guidelines recommend oral steroids as the primary treatment for Bell’s palsy and suggest the selective use of antiviral agents in severe cases or when viral involvement is strongly suspected. For severe facial palsy, such as Ramsay Hunt syndrome or varicella-zoster virus-induced cases, combination therapy may improve outcomes and reduce sequelae; however, high-quality evidence is limited. Steroid therapy is the main treatment of Bell’s palsy and antiviral therapy can be added in severe cases to improve prognosis. Additional research is required to develop standardized guidelines, concerning the use of antiviral therapies in conjunction with steroids.
10.Constitutional Chromosome 21 Abnormality in B-ALL with iAMP21 in a Patient Developing Treatment-Related Myelodysplastic Syndrome
Inhwa KIM ; Su Hyun YOON ; Sunghan KANG ; Kyung-Nam KOH ; Mi Young KIM ; Young-Uk CHO ; Sang-Hyun HWANG ; Seongsoo JANG ; Eul-Ju SEO ; Beom Hee LEE ; Sunghee MIN ; Hyunwoo BAE ; Ho Joon IM ; Hyery KIM
Clinical Pediatric Hematology-Oncology 2025;32(1):23-28
The initial molecular cytogenetic characteristics of blasts plays a significant role in determining the treatment course of B-cell acute lymphoblastic leukemia (B-ALL).B-ALL with intrachromosomal amplification of chromosome 21 (iAMP21) has been well known to have unfavorable prognosis. Also, there are previously recognized germline mutations that increase the risk of ALL, such as trisomy 21, Down syndrome. This case report is about a 16-year-old girl who presented with lymphadenitis, purpura, and fever followed by initial lab of elevated white blood cell with blasts.She had some notable facial features, but no typical Down syndrome related one.Bone marrow biopsy and fluorescence in situ hybridization finalized the diagnosis as B-ALL with iAMP21, high-risk group. The minimal residual disease-negative complete remission was achieved after the induction chemotherapy with Korean multicenter high-risk protocol. However, abnormal karyotype was sustained in bone marrow. Microarrays with her buccal swab raised the possibility that the abnormal karyotype was not from the leukemic blasts but rather from the germline. Although she underwent scheduled chemotherapy uneventfully as slow early responder type, thrombocytopenia and abnormal karyotype persisted, leading to the diagnosis of acute myeloid leukemia. Additional chemotherapy and peripheral blood stem cell transplantation was performed which resulted in engraftment. This case highlights the discovery of a constitutional genetic aberration, which played like a silent yet critical background factor for B-ALL with iAMP21. As the number of reported cases are limited, the role of germline chromosome 21 mutation as the indicator for prognosis of B-ALL should be studied further.

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