Cataract Surgery Practice in the Republic of Korea: A Survey of the Korean Society of Cataract and Refractive Surgery 2020.

PURPOSE: To describe current cataract surgery practice patterns and trends among Korean ophthalmologists. METHODS: A survey was conducted among members of the Korean Society of Cataract and Refractive Surgery in October 2020. Of the 998 questionnaires, 262 (26.3%) were received for analysis. Data were analyzed using descriptive statistics and compared with those of previous surveys. RESULTS: The largest percentage of respondents (39%) had <5 years of practical experience, and 40% had >11 years of practical experience. The average, median, and mode monthly volumes of cataract surgeries performed by the Korean Society of Cataract and Refractive Surgery members were 31, 20, and 10 cases, respectively. Topical anesthesia was administered by 85% of the respondents. For intraocular lens (IOL) calculations, 96% of the respondents used optical biometry. The proportion of surgeons providing femtosecond laser-assisted cataract surgery increased significantly from 5% in 2018 to 29% in 2020. This increase was accompanied by an increase in the multifocal IOLs. Those who implant multifocal IOL for >10% of their cases increased from 16% (2018) to 29% (2020). Topical nonsteroidal anti-inflammatory drugs were prescribed postoperatively by 76% of the respondents. Most respondents (70%) prescribed these anti-inflammatory drugs for 4 weeks. CONCLUSIONS: This survey provided a comprehensive update on current cataract surgery practice in the Republic of Korea. The results highlighted the increasing use of premium IOLs, femtosecond laser-assisted cataract surgery, optical biometry, and topical anesthesia to better meet the patients' needs.

HIGHER-ORDER ABERRATIONS IN EYES WITH SILICONE OIL TAMPONADE.

PURPOSE: To investigate the changes in higher-order aberrations (HOAs) after silicone oil removal and to evaluate their associations with visual acuity. METHODS: Fifty-nine eyes of 58 patients who underwent SO removal were included. Total, corneal, and internal optic HOAs, and best-corrected visual acuity were measured before and 1 month after SO removal, and changes were compared between phakic and pseudophakic eyes. RESULTS: Total ocular and internal optic HOAs decreased significantly after SO removal both in pseudophakic (n = 40, all P < 0.001) and phakic eyes (n = 19, P = 0.017, P = 0.004). Preoperative HOAs (P < 0.001) and changes in HOAs (P = 0.006) were greater in pseudophakic eyes than in phakic eyes. Best-corrected visual acuity was significantly improved after SO removal, from 20/105 to 20/78 (P < 0.001) in pseudophakic eyes, whereas there was no difference in phakic eyes (P = 0.714). Preoperative HOAs and the reduction in HOAs after SO removal were greater in best-corrected visual acuity-improved eyes than best-corrected visual acuity-unchanged eyes (P < 0.001). CONCLUSION: Silicone oil tamponade induced an increase in HOAs, and these increases were greater in pseudophakic eyes than in phakic eyes. Silicone oil may cause additional visual impairments because of HOAs, beyond those caused by retinal diseases, particularly in pseudophakic eyes.

Loss of RNA-binding protein HuR facilitates cellular senescence through posttranscriptional regulation of TIN2 mRNA.

Cellular senescence can be induced by high levels of reactive oxygen species (ROS) produced by mitochondria. However, the mechanism by which elevated mitochondrial ROS levels are produced during replicative senescence is not yet fully understood. Here, we report that loss of the RNA-binding protein, human antigen R (HuR), during replicative senescence leads to an increase in ROS levels through enhanced mitochondrial localization of the telomeric protein TIN2. HuR binds to the 3' untranslated region of TIN2 mRNA. This association decreases TIN2 protein levels by both destabilizing TIN2 mRNA and reducing its translation. Conversely, depletion of HuR levels enhances TIN2 expression, leading to increased mitochondrial targeting of TIN2. Mitochondrial localization of TIN2 increases ROS levels, which contributes to induction and maintenance of cellular senescence. Our findings provide compelling evidence for a novel role of HuR in controlling the process of cellular senescence by regulating TIN2-mediated mitochondrial ROS production, and for a useful therapeutic route for modulating intracellular ROS levels in treating both aging-related complications and cancer.

Hsp90-binding immunophilin FKBP52 modulates telomerase activity by promoting the cytoplasmic retrotransport of hTERT.

Telomerase is a unique ribonucleoprotein enzyme that is required for continued cell proliferation. To generate catalytically active telomerase, human telomerase reverse transcriptase (hTERT) must translocate to the nucleus and assemble with the RNA component of telomerase. The molecular chaperones heat shock protein 90 (Hsp90) and p23 maintain hTERT in a conformation that enables nuclear translocation. However, the regulatory role of chaperones in nuclear transport of hTERT remains unclear. In this work, we demonstrate that immunophilin FK506-binding protein (FKBP)52 linked the hTERT-Hsp90 complex to the dynein-dynactin motor, thereby promoting the transport of hTERT to the nucleus along microtubules. FKBP52 interacted with the hTERT-Hsp90 complex through binding of the tetratricopeptide repeat domain to Hsp90 and binding of the dynamitin (Dyt) component of the dynein-associated dynactin complex to the peptidyl prolyl isomerase domain. The depletion of FKBP52 inhibited nuclear transport of hTERT, resulting in cytoplasmic accumulation. Cytoplasmic hTERT was rapidly degraded through ubiquitin (Ub)-dependent proteolysis, thereby abrogating telomerase activity. In addition, overexpression of dynamitin, which is known to dissociate the dynein-dynactin motor from its cargoes, reduced telomerase activity. Collectively, these results provide a molecular mechanism by which FKBP52 modulates telomerase activity by promoting dynein-dynactin-dependent nuclear import of hTERT.

Telomerase activates transcription of cyclin D1 gene through an interaction with NOL1.

Telomerase is a ribonucleoprotein enzyme that is required for the maintenance of telomere repeats. Although overexpression of telomerase in normal human somatic cells is sufficient to overcome replicative senescence, the ability of telomerase to promote tumorigenesis requires additional activities that are independent of its role in telomere extension. Here, we identify proliferation-associated nucleolar antigen 120 (NOL1, also known as NOP2) as a telomerase RNA component (TERC)-binding protein that is found in association with catalytically active telomerase. Although NOL1 is highly expressed in the majority of human tumor cells, the molecular mechanism by which NOL1 contributes to tumorigenesis remained unclear. We show that NOL1 binds to the T-cell factor (TCF)-binding element of the cyclin D1 promoter and activates its transcription. Interestingly, telomerase is also recruited to the cyclin D1 promoter in a TERC-dependent manner through the interaction with NOL1, further enhancing transcription of the cyclin D1 gene. Depletion of NOL1 suppresses cyclin D1 promoter activity, thereby leading to induction of growth arrest and altered cell cycle distributions. Collectively, our findings suggest that NOL1 represents a new route by which telomerase activates transcription of cyclin D1 gene, thus maintaining cell proliferation capacity.

PIAS1-mediated sumoylation promotes STUbL-dependent proteasomal degradation of the human telomeric protein TRF2.

The human telomeric protein TRF2 protects chromosome ends by facilitating their organization into the protective capping structure. Here we show that the stability of TRF2 is regulated via modification by the small ubiquitin-like modifiers (SUMO). TRF2 specifically interacts with and is sumoylated by PIAS1 in mammalian cells. The proteasome inhibitor stabilizes SUMO-conjugated TRF2 without affecting the level of unmodified TRF2, suggesting that SUMO conjugation is required for proteasomal degradation of TRF2. We also show that RNF4, a mammalian SUMO-targeted ubiquitin ligase, interacts with TRF2 in a SUMO-dependent manner and preferentially targets SUMO-conjugated TRF2 for ubiquitination. Collectively, our data demonstrate that the PIAS1-mediated sumoylation status of TRF2 serves as a molecular switch that controls the level of TRF2 at telomeres.

Involvement of SRSF11 in cell cycle-specific recruitment of telomerase to telomeres at nuclear speckles.

Telomerase, a unique ribonucleoprotein complex that contains the telomerase reverse transcriptase (TERT), the telomerase RNA component (TERC) and the TERC-binding protein dyskerin, is required for continued cell proliferation in stem cells and cancer cells. Here we identify SRSF11 as a novel TERC-binding protein that localizes to nuclear speckles, subnuclear structures that are enriched in pre-messenger RNA splicing factors. SRSF11 associates with active telomerase enzyme through an interaction with TERC and directs it to nuclear speckles specifically during S phase of the cell cycle. On the other hand, a subset of telomeres is shown to be constitutively present at nuclear speckles irrespective of cell cycle phase, suggesting that nuclear speckles could be the nuclear sites for telomerase recruitment to telomeres. SRSF11 also associates with telomeres through an interaction with TRF2, which facilitates translocation of telomerase to telomeres. Depletion of SRSF11 prevents telomerase from associating with nuclear speckles and disrupts telomerase recruitment to telomeres, thereby abrogating telomere elongation by telomerase. These findings suggest that SRSF11 acts as a nuclear speckle-targeting factor that is essential for telomerase association with telomeres through the interactions with TERC and TRF2, and provides a potential target for modulating telomerase activity in cancer.

Akt-mediated phosphorylation increases the binding affinity of hTERT for importin α to promote nuclear translocation.

Telomeres are essential for chromosome integrity and protection, and their maintenance requires the ribonucleoprotein enzyme telomerase. Previously, we have shown that human telomerase reverse transcriptase (hTERT) contains a bipartite nuclear localization signal (NLS; residues 222-240) that is responsible for nuclear import, and that Akt-mediated phosphorylation of residue S227 is important for efficient nuclear import of hTERT. Here, we show that hTERT binds to importin-α proteins through the bipartite NLS and that this heterodimer then forms a complex with importin-ß proteins to interact with the nuclear pore complex. Depletion of individual importin-α proteins results in a failure of hTERT nuclear import, and the resulting cytoplasmic hTERT is degraded by ubiquitin-dependent proteolysis. Crystallographic analysis reveals that the bipartite NLS interacts with both the major and minor sites of importin-α proteins. We also show that Akt-mediated phosphorylation of S227 increases the binding affinity for importin-α proteins and promotes nuclear import of hTERT, thereby resulting in increased telomerase activity. These data provide details of a binding mechanism that enables hTERT to interact with the nuclear import receptors and of the control of the dynamic nuclear transport of hTERT through phosphorylation.

DNA-PKcs-interacting protein KIP binding to TRF2 is required for the maintenance of functional telomeres.

Human telomeres associate with shelterin, a six-protein complex that protects chromosome ends from being recognized as sites of DNA damage. The shelterin subunit TRF2 (telomeric repeat-binding factor 2) protects telomeres by facilitating their organization into the protective capping structure. We have reported previously that the DNA-PKcs (DNA-dependent protein kinase catalytic subunit)-interacting protein KIP associates with telomerase through an interaction with hTERT (human telomerase reverse transcriptase). In the present study, we identify KIP as a novel interacting partner of TRF2. KIP is able to interact with both TRF2 and DNA-PKcs at telomeres. Because KIP is required for the association between TRF2 and DNA-PKcs, the interplay of these three proteins may provide a mechanism for the recruitment of DNA-PKcs to telomeres. We also show that KIP binding to TRF2 enhances the telomere-binding activity of TRF2, suggesting that KIP acts as a positive regulator of TRF2 function. Furthermore, depletion of KIP induces DNA-damage response foci at telomeres, thereby leading to induction of growth arrest, cellular senescence and altered cell cycle distribution. Collectively, our findings suggest that KIP, in addition to its association with catalytically active telomerase, plays important roles in the maintenance of functional telomeres and the regulation of telomere-associated DNA-damage response. Thus KIP represents a new pathway for modulating telomerase and telomere function in cancer.

Catalytically active telomerase holoenzyme is assembled in the dense fibrillar component of the nucleolus during S phase.

The maintenance of human telomeres requires the ribonucleoprotein enzyme telomerase, which is composed of telomerase reverse transcriptase (TERT), telomerase RNA component, and several additional proteins for assembly and activity. Telomere elongation by telomerase in human cancer cells involves multiple steps including telomerase RNA biogenesis, holoenzyme assembly, intranuclear trafficking, and telomerase recruitment to telomeres. Although telomerase has been shown to accumulate in Cajal bodies for association with telomeric chromatin, it is unclear where and how the assembly and trafficking of catalytically active telomerase is regulated in the context of nuclear architecture. Here, we show that the catalytically active holoenzyme is initially assembled in the dense fibrillar component of the nucleolus during S phase. The telomerase RNP is retained in nucleoli through the interaction of hTERT with nucleolin, a major nucleolar phosphoprotein. Upon association with TCAB1 in S phase, the telomerase RNP is transported from nucleoli to Cajal bodies, suggesting that TCAB1 acts as an S-phase-specific holoenzyme component. Furthermore, depletion of TCAB1 caused an increase in the amount of telomerase RNP associated with nucleolin. These results suggest that the TCAB1-dependent trafficking of telomerase to Cajal bodies occurs in a step separate from the holoenzyme assembly in nucleoli. Thus, we propose that the dense fibrillar component is the provider of active telomerase RNP for supporting the continued proliferation of cancer and stem cells.

Hsp90 rescues PTK6 from proteasomal degradation in breast cancer cells.

PTK6 [protein tyrosine kinase 6; also known as Brk (breast tumour kinase)] is a non-receptor tyrosine kinase, closely related to Src, but evolutionarily distinct, that is up-regulated in various cancers, including breast cancer. Hsp90 (heat-shock protein 90) was identified as a PTK6-interacting protein in HEK (human embryonic kidney)-293 cells overexpressing PTK6. Hsp90 interacted with the PTK6 tyrosine kinase catalytic domain, but catalytic activity was not required for the interaction. Geldanamycin, an Hsp90 inhibitor, significantly decreased the PTK6 protein level through proteasome-dependent degradation, but did not affect the level of Src. Geldanamycin treatment also decreased phosphorylation of PTK6 substrates due to reduced amounts of PTK6. Moreover, overexpression of CHIP [C-terminus of Hsc70 (heat-shock cognate 70)-interacting protein], a chaperone-dependent E3 ligase, enhanced proteosomal degradation of PTK6. Geldanamycin increased the interaction of PTK6 with CHIP, but decreased the interaction of PTK6 with Hsp90. We also found that endogenous PTK6 associated with Hsp90 and geldanamycin decreased expression of endogenous PTK6 in breast carcinoma cells. Finally, we report that silencing endogenous CHIP expression in breast carcinoma cells inhibited geldanamycin-induced PTK6 reduction. These results demonstrate that Hsp90 plays an essential role in regulating PTK6 stability and suggest that Hsp90 inhibitors may be useful as therapeutic drugs for PTK6-positive cancers, including breast cancer.

Nuclear import of hTERT requires a bipartite nuclear localization signal and Akt-mediated phosphorylation.

Sustained cell proliferation requires telomerase to maintain functional telomeres that are essential for chromosome integrity and protection. Although nuclear import of telomerase transcriptase (hTERT) is required for telomerase activity to elongate telomeres in vivo, the molecular mechanism regulating nuclear localization of hTERT is unclear. We have identified a bipartite nuclear localization signal (NLS; amino acid residues 222-240) that is responsible for nuclear import of hTERT. Immunofluorescence imaging of hTERT revealed that mutations in any of the bipartite NLS sequences result in decreased nuclear fluorescence intensity compared with wild-type hTERT. We also show that Akt-mediated phosphorylation at serine 227 is necessary for directing nuclear translocation of hTERT. Interestingly, serine 227 is located between two clusters of basic amino acids in the bipartite NLS. Inactivation of Akt activity by a dominant-negative mutant or wortmannin treatment attenuated nuclear localization of hTERT. We further show that both bipartite NLS and serine 227 in hTERT are required for cell immortalization of normal human foreskin fibroblast cells. Taken together, our findings reveal a previously unknown regulatory mechanism for nuclear import of hTERT through a bipartite NLS mediated by Akt phosphorylation, which represents an alternative pathway for modulating telomerase activity in cancer.

The AAA-ATPase NVL2 is a telomerase component essential for holoenzyme assembly.

Continued cell proliferation requires telomerase to maintain functional telomeres that are essential for chromosome integrity. Although the core enzyme includes a telomerase reverse transcriptase (TERT) and a telomerase RNA component (TERC), a number of auxiliary proteins have been identified to regulate telomerase assembly, localization, and enzymatic activity. Here we describe the characterization of the AAA-ATPase NVL2 as a novel hTERT-interacting protein. NVL2 interacts and co-localizes with hTERT in the nucleolus. NLV2 is also found in association with catalytically competent telomerase in cell lysates through an interaction with hTERT. Depletion of endogenous NVL2 by small interfering RNA led to a decrease in hTERT without affecting the steady-state levels of hTERT mRNA, thereby reducing telomerase activity, suggesting that NVL2 is an essential component of the telomerase holoenzyme. We also found that ATP-binding activity of NVL2 is required for hTERT binding as well as telomerase assembly. Our findings suggest that NVL2, in addition to its role in ribosome biosynthesis, is essential for telomerase biogenesis and provides an alternative approach for inhibiting telomerase activity in cancer.

Fermented garlic protects diabetic, obese mice when fed a high-fat diet by antioxidant effects.

This study examined the bioactivity of yeast (Saccharomyces cerevisiae)-fermented aged black garlic (FBG) on obese mice supplied a high-fat diet (HFD) and its in vitro antioxidant activity. Aged black garlic (BG) exhibits potent antioxidative effects and has been subjected to extensive research. In addition, the bioactivity of some natural products is increased by fermentation. In a preliminary test, this study found that the antioxidant activity of FBG is stronger than that of BG. Therefore, it was hypothesized that the bioactivity of BG would be increased by yeast fermentation and would be a good candidate as a nutraceutical product for improving the oxidative defense systems in older patients or patients affected by various oxidative stresses, for example, diabetes and diabetic complications. To test this hypothesis, the bioactivities of FBG in diabetic and obese mice as well as the antioxidant activity in vitro were examined. After 91 days of continuous HFD supply, the mice showed marked obesity, hyperglycemia, hyperlipemia, and liver and kidney damages. Black garlic and all 3 different doses of FBG showed favorable hepatoprotective, nephroprotective, hypolipidemic, and antiobesity effects compared with the HFD control, but no hypoglycemic effects. In particular, more favorable bioactivity against all 4 HFD-induced diabetic complications was detected in the FBG-treated groups compared with the group given equivalent doses of BG. These findings suggest that the bioactivities of BG can be improved by yeast fermentation.

Requirement of DDX39 DEAD box RNA helicase for genome integrity and telomere protection.

Human chromosome ends associate with shelterin, a six-protein complex that protects telomeric DNA from being recognized as sites of DNA damage. The shelterin subunit TRF2 has been implicated in the protection of chromosome ends by facilitating their organization into the protective capping structure and by associating with several accessory proteins involved in various DNA transactions. Here we describe the characterization of DDX39 DEAD-box RNA helicase as a novel TRF2-interacting protein. DDX39 directly interacts with the telomeric repeat binding factor homology domain of TRF2 via the FXLXP motif (where X is any amino acid). DDX39 is also found in association with catalytically competent telomerase in cell lysates through an interaction with hTERT but has no effect on telomerase activity. Whereas overexpression of DDX39 in telomerase-positive human cancer cells led to progressive telomere elongation, depletion of endogenous DDX39 by small hairpin RNA (shRNA) resulted in telomere shortening. Furthermore, depletion of DDX39 induced DNA-damage response foci at internal genome as well as telomeres as evidenced by telomere dysfunction-induced foci. Some of the metaphase chromosomes showed no telomeric signal at chromatid ends, suggesting an aberrant telomere structure. Our findings suggest that DDX39, in addition to its role in mRNA splicing and nuclear export, is required for global genome integrity as well as telomere protection and represents a new pathway for telomere maintenance by modulating telomere length homeostasis.

Effect of DHU001, a Polyherbal Formula on Formalin-induced Paw Chronic Inflammation of Mice.

The effect of DHU001, a mixed herbal formula consisted of 7 types aqueous extracts for various respiratory disorders were evaluated on the formalin-induced paw chronic inflammation in mice after oral administration. Mice were subaponeurotically injected in the left hind paw with 0.02 ml of 3.75% formalin, then subjected to 500, 250 and 125 mg/kg of DHU001 oral administration, once a day for 10 days during which then the hind-paw thickness and volume were measured daily. The paw wet-weight, histological profiles, histomorphometrical analyses and paw tumor necrosis factor (TNF)-α contents were conducted at termination. After two formalin treatments, a marked increase in the paw thickness and volume was detected in the formalin-injected control as compared with that in the intact control, plus at the time of sacrifice the paw wet-weights, paw TNF-α contents were also dramatically increased with severe chronic inflammation signs at histopathological observations. However, these formalin-induced chronic inflammatory changes were dramatically decreased by treatment of dexamethasone and all three different dosages of DHU001. DHU001 has favorable effects on formalin-induced chronic inflammation mediated by TNF-α suppression, and DHU001 may represent an alternative approach for the treatment of chronic inflammatory diseases.

CHIP promotes human telomerase reverse transcriptase degradation and negatively regulates telomerase activity.

The maintenance of eukaryotic telomeres requires telomerase, which is minimally composed of a telomerase reverse transcriptase (TERT) and an associated RNA component. Telomerase activity is tightly regulated by expression of human (h) TERT at both the transcriptional and post-translational levels. The Hsp90 and p23 molecular chaperones have been shown to associate with hTERT for the assembly of active telomerase. Here, we show that CHIP (C terminus of Hsc70-interacting protein) physically associates with hTERT in the cytoplasm and regulates the cellular abundance of hTERT through a ubiquitin-mediated degradation. Overexpression of CHIP prevents nuclear translocation of hTERT and promotes hTERT degradation in the cytoplasm, thereby inhibiting telomerase activity. In contrast, knockdown of endogenous CHIP results in the stabilization of cytoplasmic hTERT. However, it does not affect the level of nuclear hTERT and has no effect on telomerase activity and telomere length. We further show that the binding of CHIP and Hsp70 to hTERT inhibits nuclear translocation of hTERT by dissociating p23. However, Hsp90 binding to hTERT was not affected by CHIP overexpression. These results suggest that CHIP can remodel the hTERT-chaperone complexes. Finally, the amount of hTERT associated with CHIP peaks in G(2)/M phases but decreases during S phase, suggesting a cell cycle-dependent regulation of hTERT. Our data suggest that CHIP represents a new pathway for modulating telomerase activity in cancer.

Endoscopic findings and clinical features of esophageal tuberculosis.

OBJECTIVE: Mycobacterial involvement of the esophagus is rare. Similar abnormal lesions of the esophagus may be confused with esophageal cancer and deep fungal infections. We studied the clinical features, endoscopic findings, the role of histopathology, and the outcome of antituberculosis treatment in patients with esophageal tuberculosis. METHODS: A single center based, retrospective study was performed. We reviewed the clinical and pathological records of patients with esophageal tuberculosis that were clinically diagnosed from 1997 to 2006. RESULTS: Esophageal tuberculosis, confirmed by histology, was found in six patients. Five patients presented with local symptoms. The mean number of endoscopic sessions for a diagnosis was 1.8 sessions (range 1-3). For the histopathology, caseous necrosis was found in four patients but positive acid fast bacilli stains and tuberculosis-polymerase chain reaction were not detected. Patients diagnosed with esophageal tuberculosis tolerated medical therapy and responded well. CONCLUSION: Because esophageal tuberculosis presents with various, diverse clinical features, and endoscopic findings, it is difficult to diagnose at one session of endoscopy. However, esophageal tuberculosis should be considered in the differential diagnosis if ulcerative lesions were found in the mid esophagus.

Endoscopic resection of duodenal neoplasms: a single-center study.

BACKGROUND: Premalignant duodenal lesions such as adenomas are rare. Surgical resection has been the standard approach to the treatment of these lesions. Endoscopic resection of superficial premalignant or malignant lesions of the gastrointestinal tract is used with increasing frequency. This study aimed to evaluate the safety and efficacy of endoscopic resection of duodenal neoplasms. METHODS: Patients with nonampullary duodenal adenomas or duodenal adenocarcinomas without familial polyposis syndrome between August 2002 and February 2009 were retrospectively analyzed. Data including location and size, technique used for the endoscopic resection, complications, and follow-up evaluation of the lesions were reviewed. RESULTS: The study enrolled 24 patients with duodenal neoplasms. Of these patients, 23 had duodenal adenomas and 1 had an adenocarcinoma confined to the mucosa. The mean age of the patients was 57 years (range, 40-82). In terms of location, 12 lesions (50%, 12/24) were found in the second portion of the duodenum, and 11 (45.8%, 11/24) were found in the first portion. Tubular adenomas were the most common type (17/24, 70.8%). There were four cases of the villotubular type and three of the villous type. Conventional endoscopic mucosal resection (EMR) was performed for 19 patients, EMR with ligation (EMR-L) for 3 patients, and snare polypectomy for 2 patients. Complete resection was achieved for 87.5% (21/24) of the patients, and the recurrence rate was 8.3% (2/24). All the complications were intraprocedural bleeding (n = 7), with no occurrence of perforation or infection. During a median follow-up period of 6 months (range, 3-36 months), recurrence of the duodenal neoplasm was observed in two cases. There was no procedure-related mortality. CONCLUSIONS: Endoscopic resection of duodenal neoplasms was safe and effective treatment. During the short-term follow-up evaluation, EMR showed outcomes and complications comparable with prior procedures, including adenocarcinomas confined to the mucosa.