Modern drug discovery is driven by high demand in the pharmaceutical industry to test growing libraries of compounds against potential targets. High-throughput screening (HTS) is characterized by fully automated experimentation that leverages robotic liquid handling systems, analytical techniques, and advanced computing and statistics, including the recent integration of artificial intelligence. To align with this trend, it is crucial to develop and implement new HTS platforms that offer improved predictivity and physiological relevance. In recent years, microphysiological systems, commonly known as organ-on-chip (OoC) systems, have progressed from a theoretical concept to a powerful alternative to conventional in vitro and animal models. High-throughput OoC (HT-OoC) systems could represent the disruptive technology sought by pharmaceutical companies to address their enormous research and development (R&D) expenses. In this study, we provide a brief overview of commercial products utilizing modern HT-OoC systems in drug discovery and development. Additionally, we discuss recent trends in R&D aimed at industrialization.

Background/Aims: Inaccurate prediction of lymph node metastasis (LNM) may lead to unnecessary surgery following endoscopic resection of T1 colorectal cancer (CRC). We aimed to validate the usefulness of artificial intelligence (AI) models for predicting LNM in patients with T1 CRC. Methods: We analyzed the clinical data, laboratory results, pathological reports, and endoscopic findings of patients who underwent radical surgery for T1 CRC. We developed AI models to predict LNM using four algorithms: regularized logistic regression classifier (RLRC), random forest classifier (RFC), CatBoost classifier (CBC), and the voting classifier (VC). Four histological factors and four endoscopic findings were included to develop AI models. Areas under the receiver operating characteristics curves (AUROCs) were measured to distinguish AI model performance in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines. Results: Among 1,386 patients with T1 CRC, 173 patients (12.5%) had LNM. The AUROC values of the RLRC, RFC, CBC, and VC models for LNM prediction were significantly higher (0.673, 0.640, 0.679, and 0.677, respectively) than the 0.525 suggested in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines (vs RLRC, p<0.001; vs RFC, p=0.001; vs CBC, p<0.001; vs VC, p<0.001). The AUROC value was similar between T1 colon versus T1 rectal cancers (0.718 vs 0.615, p=0.700). The AUROC value was also similar between the initial endoscopic resection and initial surgery groups (0.581 vs 0.746, p=0.845). Conclusions AI models trained on the basis of endoscopic findings and pathological features performed well in predicting LNM in patients with T1 CRC regardless of tumor location and initial treatment method.

Background/Aims: The study investigated the incidence, risk factors, and clinical outcomes of chronic antibiotic-refractory pouchitis (CARP) in Korean patients with ulcerative colitis (UC). Methods: This single-center retrospective study included patients with UC who underwent total proctocolectomy with ileal pouch-anal anastomosis at the Asan Medical Center in Korea between January 1987 and December 2022. The primary outcomes were endoscopic remission and pouch failure. The Cox’s proportional hazard model was used to identify the risk factors for CARP. Results: The clinical data of 232 patients were analyzed. The most common cause of surgery was steroid refractoriness (50.9%), followed by dysplasia/colorectal cancer (26.7%). Among 74 patients (31.9%) with chronic pouchitis (CP), 31 (13.4%) had CARP, and 43 (18.5%) had chronic antibiotic-dependent pouchitis (CADP). The most frequent endoscopic phenotype was focal inflammation of the pouch (CP, 47.3%; CARP, 35.5%; CADP, 55.8%). Patients with CARP were less likely to use concomitant probiotics than patients with CADP (29.0% vs 72.1%, p<0.01). The endoscopic remission rate of CP, CARP, and CADP was 14.9%, 9.7%, and 18.6%, respectively.The pouch failure rate associated with CP, CARP, and CADP was 13.5%, 16.1%, and 11.6%, respectively. Current smoking status (adjusted hazard ratio [aHR], 2.96; 95% confidence interval [CI], 1.27 to 6.90; p=0.01) and previous use of biologics/small molecules (aHR, 2.40; 95% CI, 1.05 to 5.53; p=0.04) were significantly associated with CARP development. Conclusions UC patients who were current smokers and previously used biologics/small molecules had a higher risk of developing CARP. Concomitant use of probiotics was less likely to be associated with CARP development.

Background: The World Health Organization has declared the end of the coronavirus disease 2019 (COVID-19) public health emergency. However, this did not indicate the end of COVID-19. Several months after the infection, numerous patients complain of respiratory or nonspecific symptoms; this condition is called long COVID. Even patients with mild COVID-19 can experience long COVID, thus the burden of long COVID remains considerable. Therefore, we conducted this study to comprehensively analyze the effects of long COVID using multi-faceted assessments. Materials and Methods: We conducted a prospective cohort study involving patients diagnosed with COVID-19 between February 2020 and September 2021 in six tertiary hospitals in Korea. Patients were followed up at 1, 3, 6, 12, 18, and 24 months after discharge. Long COVID was defined as the persistence of three or more COVID-19-related symptoms. The primary outcome of this study was the prevalence of long COVID after the period of COVID-19. Results: During the study period, 290 patients were enrolled. Among them, 54.5 and 34.6% experienced long COVID within 6 months and after more than 18 months, respectively. Several patients showed abnormal results when tested for post-traumatic stress disorder (17.4%) and anxiety (31.9%) after 18 months. In patients who underwent follow-up chest computed tomography 18 months after COVID-19, abnormal findings remained at 51.9%. Males (odds ratio [OR], 0.17; 95% confidence interval [CI], 0.05–0.53; P=0.004) and elderly (OR, 1.04; 95% CI, 1.00–1.09; P=0.04) showed a significant association with long COVID after 12–18 months in a multivariable logistic regression analysis. Conclusion Many patients still showed long COVID after 18 months post SARS-CoV-2 infection. When managing these patients, the assessment of multiple aspects is necessary.

Purpose: Myocardial strain imaging is a promising tool for evaluating altered cardiac wall mechanics in thickened myocardium. Circumferential transmural strain difference (cTSD) can be readily measured using feature-tracking magnetic resonance imaging (MRI). This study aimed to explore the correlations between cTSD and other markers of disease in apical hypertrophic cardiomyopathy (ApHCM). Materials and Methods: A retrospective, single-center, case-control study was conducted on patients with ApHCM who underwent 1.5-T or 3.0-T cardiac MRI. Left ventricular (LV) longitudinal and circumferential strains were analyzed using feature-tracking software. cTSD was calculated as the difference between epicardial and endocardial circumferential strains. Global and segmental strains were compared between groups, and correlations between cTSD and LV mass or late gadolinium enhancement (LGE) were analyzed. Results: A total of 29 participants (17 patients with ApHCM, median age 64 years, 71% men; 12 normal controls, median age 55 years, 67% men) were evaluated. Global and segmental cTSD were significantly higher in the ApHCM group than in the normal group from the base to the apex, with the greatest differences at the apex (base 19.6% vs.16.1%, mid 24.5% vs. 16.9%, and apex 36.8% vs. 21.6%, all p < 0.05). Global cTSD showed a moderate positive correlation with indexed LV mass (ρ = 0.599, p = 0.001), while segmental cTSD showed a weak positive correlation with LGE in patients with ApHCM (ρ = 0.239, p < 0.001). Conclusion Segmental cTSD was significantly higher in the ApHCM group than in the normal group, with the greatest difference at the apical segments. This difference was not observed in the full-thickness myocardial circumferential strain. These findings suggest that cTSD may serve as a sensitive imaging biomarker for ApHCM, not only in hypertrophied apex segments but also in non-hypertrophied myocardium.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: Postoperative pain management is challenging in patients with oral cancer, especially those undergoing reconstructive surgery. Patient-controlled analgesia (PCA) is widely used, and fentanyl (FTN) concentration adjustments may improve pain control. This study aimed to evaluate the effects of FTN PCA concentration and reconstructive surgery on postoperative pain in patients with oral cancer. Methods: This retrospective observational study analyzed 140 patients with oral cancer who underwent surgery under general anesthesia. Patients were categorized based on FTN PCA dosage (FTN 700 mcg and ketorolac 150 mg vs. FTN 1400 mcg and ketorolac 150 mg). Pain was assessed using the visual analog scale (VAS) at multiple time points postoperatively (0, 12, 24, 36, 48, 60, and 72 h). PCA usage patterns, including demand count, delivery count, and delivery/demand ratios, were compared across subgroups. Missing data were imputed using linear interpolation. Results: PCA usage and pain control were evaluated between the FTN 700 mcg (N = 40) and 1400 mcg (N = 100) groups, stratified by reconstruction status. Demographic characteristics showed no significant difference.In the reconstructive surgery subgroup, patients in the FTN 1400 mcg group showed lower PCA refill counts (1.45 ± 0.69 vs. 1.61 ± 0.58) and fewer delivery counts (17.1 ± 21.3 vs. 25.1 ± 28.5) compared to those in the FTN 700 mcg group, achieving similar or superior pain control with fewer interventions. Similarly, patients without reconstructive surgery in the FTN 1400 mcg group demonstrated lower PCA refill counts, shorter PCA usage times, and fewer delivery counts. VAS scores decreased consistently over time across all groups but remained higher in the reconstruction groups. Logistic regression analysis revealed that patients with reconstructive surgery in the FTN 1400 mcg group were more likely to achieve a VAS score of ≤ 3.0 at 72 h postoperatively (P = 0.022). These findings indicate FTN 1400 mcg’s superiority in managing postoperative pain. Conclusion Comparing FTN PCA dosages, 1400 mcg demonstrated superior pain control to 700 mcg in patients undergoing oral cancer surgery, particularly those who underwent reconstructive surgery. This finding underscores the importance of optimizing FTN dosages to enhance postoperative pain management, reduce PCA-related demands, and achieve better patient outcomes.

Purpose: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.

Background: s/Aims: Hepatocellular carcinoma (HCC) is the sixth most common cancer and second leading cause of cancer-related deaths in South Korea. This study evaluated the characteristics of Korean patients newly diagnosed with HCC in 2016-2018. Methods: Data from the Korean Primary Liver Cancer Registry (KPLCR), a representative database of patients newly diagnosed with HCC in South Korea, were analyzed. This study investigated 4,462 patients with HCC registered in the KPLCR in 2016-2018. Results: The median patient age was 63 years (interquartile range, 55-72). 79.7% of patients were male. Hepatitis B infection was the most common underlying liver disease (54.5%). The Barcelona Clinic Liver Cancer (BCLC) staging system classified patients as follows: stage 0 (14.9%), A (28.8%), B (7.5%), C (39.0%), and D (9.8%). The median overall survival was 3.72 years (95% confidence interval, 3.47-4.14), with 1-, 3-, and 5-year overall survival rates of 71.3%, 54.1%, and 44.3%, respectively. In 2016-2018, there was a significant shift toward BCLC stage 0-A and Child-Turcotte-Pugh liver function class A (P<0.05), although survival rates did not differ by diagnosis year. In the treatment group (n=4,389), the most common initial treatments were transarterial therapy (31.7%), surgical resection (24.9%), best supportive care (18.9%), and local ablation therapy (10.5%). Conclusions Between 2016 and 2018, HCC tended to be diagnosed at earlier stages, with better liver function in later years. However, since approximately half of the patients remained diagnosed at an advanced stage, more rigorous and optimized HCC screening strategies should be implemented.