Efficacy and safety of first-line biological DMARDs in rheumatoid arthritis patients with chronic kidney disease.

OBJECTIVE: To evaluate the efficacy and safety of first-line biological disease-modifying antirheumatic drugs (bDMARDs) in patients with rheumatoid arthritis (RA) with chronic kidney disease (CKD), including those undergoing haemodialysis (HD). METHODS: This retrospective cohort study included 425 patients with RA prescribed their first bDMARDs at two hospitals from 2004 to 2021. Patients were categorised by kidney function and bDMARD modality (TNFα inhibitors (TNFαis), interleukin-6 inhibitors (IL-6is), cytotoxic T-lymphocyte antigen-4 immunoglobulin (CTLA4-Ig)). The primary outcome was the 36-month drug retention rate, with secondary outcomes including changes in Disease Activity Score 28 (DAS28)-C reactive protein (CRP)/erythrocyte sedimentation rate (ESR), prednisolone dosage and reasons for discontinuation. RESULTS: The 36-month drug retention rates by estimated glomerular filtration rate (eGFR) (≥60, 30-60, <30 mL/min/1.73 m2) were as follows: all bDMARDs (45.2%, 32.0%, 41.4%), TNFαis (45.3%, 28.2%, 34.0%), IL-6is (47.4%, 66.7%, 71.4%) and CTLA-4Ig (50.0%, 31.3%, 33.3%). Even in groups with lower kidney function, the drug retention rate of bDMARDs was generally maintained. However, the retention rate of TNFαis was significantly lower in patients with eGFR <30 mL/min/1.73 m2. IL-6is showed the highest retention rate and the lowest discontinuation rate due to ineffectiveness in this group (HR 0.11, 95% CI 0.02 to 0.85, p=0.03). All bDMARDs improved DAS28-CRP/ESR and reduced prednisolone dosage across all groups. CONCLUSION: bDMARDs demonstrated effective and safe profiles in patients with RA with CKD, even among patients on HD. In particular, IL-6is had a significantly higher drug retention rate in patients with an eGFR of <30 mL/min/1.73 m2 and fewer discontinuations due to ineffectiveness. IL-6is were more efficacious as monotherapy compared with the other bDMARDs.

Impact of carcinoma in situ on the outcome of intravesical Bacillus Calmette-Guérin therapy for non-muscle-invasive bladder cancer: a comparative analysis of large real-world data.

BACKGROUND: This study investigated the clinical impact of carcinoma in situ (CIS) in intravesical Bacillus Calmette-Guérin (BCG) therapy for patients with non-muscle-invasive bladder cancer (NMIBC). METHODS: This study retrospectively evaluated 3035 patients who were diagnosed with NMIBC and treated by intravesical BCG therapy between 2000 and 2019 at 31 institutions. Patients were divided into six groups according to the presence of CIS as follows: low-grade Ta without concomitant CIS, high-grade Ta without concomitant CIS, high-grade Ta with concomitant CIS, high-grade T1 without concomitant CIS, high-grade T1 with concomitant CIS, and pure CIS (without any papillary lesion). The endpoints were recurrence- and progression-free survival after the initiation of BCG therapy. We analyzed to identify factors associated with recurrence and progression. RESULTS: At a median follow-up of 44.4 months, recurrence and progression were observed in 955 (31.5%) and 316 (10.4%) patients, respectively. Comparison of six groups using univariate and multivariate analysis showed no significant association of CIS. However, CIS in the prostatic urethra was an independent factors associated with progression. CONCLUSION: Concomitant CIS did not show a significant impact in the analysis of Ta and T1 tumors which were treated using intravesical BCG. Concomitant CIS in the prostatic urethra was associated with high risk of progression. Alternative treatment approaches such as radical cystectomy should be considered for patients with NMIBC who have a risk of progression.

DNA maintenance methylation enzyme Dnmt1 in satellite cells is essential for muscle regeneration.

Epigenetic transcriptional regulation is essential for the differentiation of various types of cells, including skeletal muscle cells. DNA methyltransferase 1 (Dnmt1) is responsible for maintenance of DNA methylation patterns via cell division. Here, we investigated the relationship between Dnmt1 and skeletal muscle regeneration. We found that Dnmt1 is upregulated in muscles during regeneration. To assess the role of Dnmt1 in satellite cells during regeneration, we performed conditional knockout (cKO) of Dnmt1 specifically in skeletal muscle satellite cells using Pax7CreERT2 mice and Dnmt1 flox mice. Muscle weight and the cross-sectional area after injury were significantly lower in Dnmt1 cKO mice than in control mice. RNA sequencing analysis revealed upregulation of genes involved in cell adhesion and apoptosis in satellite cells from cKO mice. Moreover, satellite cells cultured from cKO mice exhibited a reduced number of cells. These results suggest that Dnmt1 is an essential factor for muscle regeneration and is involved in positive regulation of satellite cell number.

Uhrf1 is indispensable for normal limb growth by regulating chondrocyte differentiation through specific gene expression.

Transcriptional regulation can be tightly orchestrated by epigenetic regulators. Among these, ubiquitin-like with PHD and RING finger domains 1 (Uhrf1) is reported to have diverse epigenetic functions, including regulation of DNA methylation. However, the physiological functions of Uhrf1 in skeletal tissues remain unclear. Here, we show that limb mesenchymal cell-specific Uhrf1 conditional knockout mice (Uhrf1ΔLimb/ΔLimb ) exhibit remarkably shortened long bones that have morphological deformities due to dysregulated chondrocyte differentiation and proliferation. RNA-seq performed on primary cultured chondrocytes obtained from Uhrf1ΔLimb/ΔLimb mice showed abnormal chondrocyte differentiation. In addition, integrative analyses using RNA-seq and MBD-seq revealed that Uhrf1 deficiency decreased genome-wide DNA methylation and increased gene expression through reduced DNA methylation in the promoter regions of 28 genes, including Hspb1, which is reported to be an IL1-related gene and to affect chondrocyte differentiation. Hspb1 knockdown in cKO chondrocytes can normalize abnormal expression of genes involved in chondrocyte differentiation, such as Mmp13 These results indicate that Uhrf1 governs cell type-specific transcriptional regulation by controlling the genome-wide DNA methylation status and regulating consequent cell differentiation and skeletal maturation.

Sequential immune-targeted surgical therapy resulted in disease-free survival in a case with advanced renal cell carcinoma.

BACKGROUND: Currently, immunotherapy is indicated for patients with metastatic RCC or unresectable RCC, but there is no indication for immunotherapy in the neoadjuvant setting. We report a case in which the combined use of nivolumab and ipilimumab and sequential TKI therapy enabled surgical treatment. CASE PRESENTATION: A 71-year-old female was diagnosed with a metastatic clear-cell renal cell carcinoma with a level IV tumor thrombus. She was started on nivolumab-ipilimumab therapy, and was switched to pazopanib monotherapy because the tumor thrombus progressed within the right atrium. The tumor shrank to resectable status with sequential therapy. She then underwent right nephrectomy and thrombectomy. Pathological analysis showed 10-20% residual tumor in the primary tumor, but no viable cells in tumor thrombus. She remains clinically disease-free 1 year after surgery. CONCLUSION: This case suggests the utility of sequential immune-targeted therapy as neoadjuvant therapy in advanced renal cell carcinoma.

A low RENAL Nephrometry Score can avoid the need for the intraoperative insertion of a ureteral catheter in robot-assisted partial nephrectomy.

BACKGROUND: Intraoperative urinary collecting system entry (CSE) in robot-assisted partial nephrectomy (RAPN) may cause postoperative urinary leakage and extend the hospitalization. Therefore, identifying and firmly closing the entry sites are important for preventing postoperative urine leakage. In RAPN cases expected to require CSE, we insert a ureteral catheter and inject dye into the renal pelvis to identify the entry sites. We retrospectively analyzed the factors associated with intraoperative CSE in RAPN and explored the indications of intraoperative ureteral catheter indwelling in RAPN. METHODS: Of 104 Japanese patients who underwent RAPN at our institution from August 2016 to March 2020, 101 were analyzed. The patients were classified into CSE and non-CSE groups. The patients' background characteristics, RENAL Nephrometry Score (RNS), and surgical outcomes were analyzed. RESULTS: Intraoperative CSE was observed in 41 patients (41%). The CSE group had a significantly longer operative time, console time, ischemic time, and hospital stay than the non-CSE group. In a multivariable analysis, the N-score (odds ratio [OR] = 3.9, P < 0.05) and RNS total score excluding the L-score (OR = 3.1, P < 0.05) were associated with CSE. In a logistic regression analysis, CSE showed a moderate correlation with the RNS total score excluding the L-score (AUC 0.848, cut-off 5, sensitivity 0.83, specificity 0.73). CONCLUSION: A ureteral catheter should not be placed in patients with an RNS total score (excluding the L-score) of ≤ 4.

Predictors of Hypotension after Adrenalectomy for Pheochromocytoma.

The management of blood pressure is a significant concern for surgeons and anesthesiologists performing adrenalectomy for pheochromocytoma. We evaluated clinical factors in pheochromocytoma patients to identify the predictors of postoperative hypotension. The medical records of patients who underwent adrenalectomy for pheochromocytoma between 2001 and 2017 were retrospectively reviewed and clinical and biochemical data were evaluated. Of 29 patients, 13 patients needed catecholamine support in the perisurgical period while 16 patients did not. There were significant differences in median age, tumor size, and blood pressure drop (maxmin) between the 2 groups (68 vs 53 years old, p=0.045; 50 vs 32 mm diameter, p=0.022; 110 vs 71 mmHg, p=0.015 respectively). In univariate logistic analysis, age > 65.5 years, tumor size > 34.5 mm, urine metanephrine > 0.205 mg/day and urine normetanephrine > 0.665 mg/day were significant predictors of prolonged hypotension requiring postoperative catecholamine support. Tumor size and urine metanephrine and urine normetanephrine levels were correlated with postoperative hypotension. These predictors may help in the safe perioperative management of pheochromocytoma patients treated with adrenalectomy.

GPRC5A facilitates cell proliferation through cell cycle regulation and correlates with bone metastasis in prostate cancer.

The prognosis of patients with progressive prostate cancers that are hormone refractory and/or have bone metastasis is poor. Multiple therapeutic targets to improve prostate cancer patient survival have been investigated, including orphan GPCRs. In our study, we identified G Protein-Coupled Receptor Class C Group 5 Member A (GPRC5A) as a candidate therapeutic molecule using integrative gene expression analyses of registered data sets for prostate cancer cell lines. Kaplan-Meier analysis of TCGA data sets revealed that patients who have high GPRC5A expression had significantly shorter overall survival. PC3 prostate cancer cells with CRISPR/Cas9-mediated GPRC5A knockout exhibited significantly reduced cell proliferation both in vitro and in vivo. RNA-seq revealed that GPRC5A KO PC3 cells had dysregulated expression of cell cycle-related genes, leading to cell cycle arrest at the G2/M phase. Furthermore, the registered gene expression profile data set showed that the expression level of GPRC5A in original lesions of prostate cancer patients with bone metastasis was higher than that without bone metastasis. In fact, GPRC5A KO PC3 cells failed to establish bone metastasis in xenograft mice models. In addition, our clinical study revealed that GPRC5A expression levels in prostate cancer patient samples were significantly correlated with bone metastasis as well as the patient's Gleason score (GS). Combined assessment with the immunoreactivity of GPRC5A and GS displayed higher specificity for predicting the occurrence of bone metastasis. Together, our findings indicate that GPRC5A can be a possible therapeutic target and prognostic marker molecule for progressive prostate cancer.

Feasibility of Laparoscopic Radical Cystectomy in Elderly Patients: A Comparative Analysis of Clinical Outcomes in a Single Institution.

Laparoscopic radical cystectomy (LRC) is a standard surgical treatment for muscle-invasive bladder cancer and high-risk non-muscle-invasive bladder cancer. LRC is a less invasive modality than conventional open surgery. Therefore, even elderly patients with invasive bladder cancer may be candidates for LRC. In this study, a comparative analysis of perioperative/oncological outcomes between elderly patients and younger patients who underwent LRC was performed to assess the feasibility of LRC in elderly patients. Sixty-eight consecutive patients who underwent LRC between October 2013 and March 2018 were enrolled and stratified into those younger than 75 years (n=37) and those ≥ 75 years old (n=31). The median follow-up period was 28.2 months. The preoperative and operative parameters and complications were similar in both groups. The 2-year overall survival (OS) was 64.4% in the younger vs. 76.4% in the elderly group (p=0.053), cancer-specific survival (CSS) was 79.3% vs. 81.7% (p=0.187), and recurrence-free survival (RFS) was 58.2% vs. 75.7% (p=0.174), respectively. No significant differences were observed in OS, CSS, or RFS between the groups. No significant differences were found between the groups with respect to peri-surgical/oncological outcomes. We conclude that LRC is feasible in elderly patients.

New classification of hydronephrosis on 18F-FDG-PET/CT predicts post-operative renal function and muscle-invasive disease in patients with upper urinary tract urothelial carcinoma.

OBJECTIVES: To evaluate the value of a classification of hydronephrosis on 18F-flurodeoxyglucose (FDG)-PET/CT in predicting post-operative renal function and pathological outcomes among patients with upper urinary tract urothelial carcinoma. METHODS: We retrospectively reviewed 71 patients treated with nephroureterectomy (NU) for upper urinary tract urothelial carcinoma after FDG-PET/CT between 2010 and 2016. Eight patients treated with ureteral stent or nephrostomy at the time of FDG-PET/CT were excluded. We classified hydronephrosis based on renal excretion of FDG as follows: Type 0, no hydronephrosis; Type 1, hydronephrosis with FDG excretion; and Type 2, hydronephrosis without FDG excretion. eGFR was recorded before pre-operataive FDG-PET/CT examination and after nephroureterectomy. RESULTS: Thirty-three patients (52%) had hydronephrosis, classified as Type 1 in 19 patients (30%) and Type 2 in 14 (22%). Type 2 hydronephrosis was associated with ureteral cancer and severe hydronephrosis on CT. Median changes in eGFR before and after nephroureterectomy in patients classified as Type 0, 1 and 2 were -23.9, -18.8 and 2.0 ml/min/1.73 m2, respectively. On multivariate analysis, Type 2 hydronephrosis was a significant predictor of change in eGFR (P = 0.001). Rates of muscle-invasive upper urinary tract urothelial carcinoma among Type 0, 1 and 2 patients were 37, 42 and 86%, respectively. On multivariate analysis, Type 2 hydronephrosis was a significant predictor of muscle-invasive upper urinary tract urothelial carcinoma (P = 0.032, OR 6.491). CONCLUSIONS: This classification of hydronephrosis from FDG-PET/CT is simple and useful for predicting post-operative renal function and muscle-invasive disease in patients with upper urinary tract urothelial carcinoma, especially with ureteral cancer. This classification can help in deciding eligibility for lymphadenectomy or perioperative cisplatin-based chemotherapy.

Patient-reported outcomes after robot-assisted radical prostatectomy and institutional learning curve for functional outcomes.

Purpose: The study was performed to examine patient-reported outcomes (PROs) in the 1st year after surgery and the institutional learning curve after the introduction of robot-assisted radical prostatectomy (RARP). Materials and Methods: The subjects were 320 consecutive patients who underwent RARP from 2014 to 2018. These cases were divided into three groups treated in the early, middle, and late periods, with about 100 cases in each. PROs were recorded using the Expanded Prostate Cancer Index Composite (EPIC). Results: There were no significant differences among the early, middle, and late periods based on EPIC scores. Urinary function and bother decreased in the 1st month after surgery, and gradually recovered thereafter. However, urinary function was significantly worse in the 1st year after surgery than at baseline. Urinary function and bother were better in patients treated with nerve-sparing surgery, and in nerve-sparing cases, urinary function and bother were best in the early period and worst in the late period. These cases also had the best score for sexual function in the early period, but sexual bother was worst in the early period. In contrast, in cases treated without nerve-sparing surgery, urinary function and bother were best in the late period and worst in the early period, although without significant differences. Conclusion: The functional results of this study based on PROs are useful for providing information for patients. Interestingly, the institutional learning curves for RARP differed in cases that did and did not undergo a nerve-sparing procedure.

Efficacy of SGLT2 inhibitors in IgA nephropathy associated with alcoholic liver cirrhosis accompanied by nephrotic syndrome: a case report.

We present a 51-year-old male patient with a history of Child-Pugh Grade B alcoholic liver cirrhosis (ALC) who developed renal impairment (serum creatinine of 2.00 mg/dL) and nephrotic syndrome (a urinary protein level of 4.35 g/gCr). The patient was diagnosed with immunoglobulin A nephropathy (IgAN) associated with ALC based on findings from comprehensive evaluations, including markedly elevated serum IgA levels (883.7 mg/dL), a kidney biopsy revealing significant IgA deposition in the para-mesangial area, and a liver diagnosis showing long-standing advanced ALC. Our treatment approach involved initiating dapagliflozin therapy, a sodium-glucose cotransporter-2 (SGLT2) inhibitor, alongside strict alcohol abstinence. Remarkably, the patient demonstrated a dramatic reduction in proteinuria within one week of dapagliflozin administration. No hypoglycemic events were observed. This case adds valuable clinical insights into the potential therapeutic role of SGLT2 inhibitors in IgAN associated with ALC. Specifically, in cases where conventional steroid therapies may be contraindicated due to coexisting comorbidities such as diabetes or obesity, dapagliflozin emerges as a potentially efficacious alternative. Further investigations are warranted to validate these preliminary observations.

Uhrf1 governs the proliferation and differentiation of muscle satellite cells.

DNA methylation is an essential form of epigenetic regulation responsible for cellular identity. In muscle stem cells, termed satellite cells, DNA methylation patterns are tightly regulated during differentiation. However, it is unclear how these DNA methylation patterns affect the function of satellite cells. We demonstrate that a key epigenetic regulator, ubiquitin like with PHD and RING finger domains 1 (Uhrf1), is activated in proliferating myogenic cells but not expressed in quiescent satellite cells or differentiated myogenic cells in mice. Ablation of Uhrf1 in mouse satellite cells impairs their proliferation and differentiation, leading to failed muscle regeneration. Uhrf1-deficient myogenic cells exhibited aberrant upregulation of transcripts, including Sox9, with the reduction of DNA methylation level of their promoter and enhancer region. These findings show that Uhrf1 is a critical epigenetic regulator of proliferation and differentiation in satellite cells, by controlling cell-type-specific gene expression via maintenance of DNA methylation.

Extended robot-assisted laparoscopic prostatectomy and extended pelvic lymph node dissection as a monotherapy in patients with very high-risk prostate cancer Patients.

BACKGROUND: Patients with very-high-risk prostate cancer (VHRPCa) have earlier biochemical recurrences (BCRs) and higher mortality rates. It remains unknown whether extended robot-assisted laparoscopic prostatectomy (eRALP) without neoadjuvant or adjuvant therapy can improve the outcomes of VHRPCa patients. We aimed to determine the feasibility and efficacy of eRALP as a form of monotherapy for VHRPCa. METHODS: Data from 76 men who were treated with eRALP without neoadjuvant/adjuvant therapy were analyzed. eRALP was performed using an extrafascial approach. Extended pelvic lymph node (LN) dissection (ePLND) included nodes above the external iliac axis, in the obturator fossa, and around the internal iliac artery up to the ureter. The outcome measures were BCR, treatment failure (defined as when the prostate-specific antigen level did not decrease to <0.1 ng/ml postoperatively), and urinary continence (UC). Kaplan-Meier, logistic regression, and Cox proportional-hazards model were used to analyze the data. RESULTS: The median operative time was 246 min, and median blood loss was 50 ml. Twenty-one patients experienced postoperative complications. Median follow-up was 25.2 months; 19.7% of patients had treatment failure. Three-year, BCR-free survival rate was 62.0%. Castration-resistant prostate cancer-free survival rate was 86.1%. Overall survival was 100%. In 55 patients who had complete postoperative UC data, 47 patients (85.5%) recovered from their UC within 12 months. Clinical stage cT3b was an independent preoperative treatment failure predictor (p = 0.035), and node positivity was an independent BCR predictor (p = 0.037). The small sample size and retrospective nature limited the study. CONCLUSIONS: This approach was safe and produced acceptable UC-recovery rates. Preoperative seminal vesicle invasion is associated with treatment failure, and pathological LN metastases are associated with BCR. Therefore, our results may help informed decisions about neoadjuvant or adjuvant therapies in VHRPCa cases. PRECIS: Extended robot-assisted laparoscopic prostatectomy and extended pelvic lymph node dissection without adjuvant therapy is safe and effective for some patients with very-high-risk prostate cancer. The clinical stage and node positivity status predicted monotherapy failure, which may indicate good adjuvant therapy candidate.

Myofiber androgen receptor increases muscle strength mediated by a skeletal muscle splicing variant of Mylk4.

Androgens have a robust effect on skeletal muscles to increase muscle mass and strength. The molecular mechanism of androgen/androgen receptor (AR) action on muscle strength is still not well known, especially for the regulation of sarcomeric genes. In this study, we generated androgen-induced hypertrophic model mice, myofiber-specific androgen receptor knockout (cARKO) mice supplemented with dihydrotestosterone (DHT). DHT treatment increased grip strength in control mice but not in cARKO mice. Transcriptome analysis by RNA-seq, using skeletal muscles obtained from control and cARKO mice treated with or without DHT, identified a fast-type muscle-specific novel splicing variant of Myosin light-chain kinase 4 (Mylk4) as a target of AR in skeletal muscles. Mylk4 knockout mice exhibited decreased maximum isometric torque of plantar flexion and passive stiffness of myofibers due to reduced phosphorylation of Myomesin 1 protein. This study suggests that androgen-induced skeletal muscle strength is mediated with Mylk4 and Myomesin 1 axis.

[Chronic myeloid leukemia complicated with cerebellar hemorrhage and acute hydrocephalus successfully treated with imatinib and intensive supportive care].

We report a case of a 46-year-old female demonstrating general fatigue and visual disturbances with retinal bleeding. She had a white blood cell count of 419,300/mm. Thereafter, she developed vomiting associated with vertigo caused by cerebellar hemorrhage, deteriorating to acute hydrocephalus secondary to obstruction of the cerebral aqueduct. Emergency procedures for cerebral protection, such as hyperventilation, administration of mannitol, and barbiturate coma, were performed. Bone marrow examination showed a positive BCR-ABL/t(9;22)(q34;q11) chromosomal translocation detected by FISH and RT-PCR (masked Ph) and she was diagnosed as having chronic myeloid leukemia (CML) in the chronic phase (CP). She was administered Ara-C, together with imatinib 600 mg/d through a nasogastric tube. Eight days later, she underwent successful extubation and recovered without any neurological defect. She was maintained on imatinib 400 mg/d and demonstrated a major molecular response at 15 months. Physicians need to be aware that brain hemorrhage may develop as an initial symptom of CML patients in CP.

Zscan10 suppresses osteoclast differentiation by regulating expression of Haptoglobin.

Zinc finger and SCAN domain containing 10 (Zscan10) was identified as a novel transcription factor that is involved in osteoclast differentiation in our previous report. However, the biological functions of Zscan10 are not fully understood except its roles in the maintenance of genome stability and pluripotency of embryonic stem cells. Therefore, the purpose of this study was to clarify the function of Zscan10 in somatic cells, especially during osteoclast differentiation. First, Zscan10 KO RAW264 (KO) cells were established by genome editing using CRISPR/Cas9 and single cell sorting. Then, control (Ctrl) and KO cells were differentiated into osteoclasts by RANKL stimulation. We observed that TRAP activity and the expression levels of differentiation marker genes, such as Nfatc1, were significantly increased and the expression of inhibitory factors, such as Irf8, was decreased in KO cells compared to Ctrl cells. These results suggest that Zscan10 might regulate transcription of the genes that negatively control osteoclastogenesis. To understand gene expression profiles controlled by Zscan10, RNA-seq was performed and stringent analyses identified the haptoglobin gene (Hp) as a possible target of Zscan10. In addition, ChIP against Zscan10 revealed that Zscan10 could interact with its binding motif located near the Hp gene locus as well as the transcription start site of Hp, suggesting that Zscan10 can directly regulate transcription of Hp. Finally, to examine the effects of Hp on osteoclastogenesis, KO cells were treated with recombinant Hp (rHp). rHp treatment suppressed TRAP activity of KO cells without affecting cell viability. Furthermore, it has been reported that Hp KO mice exhibit decreased bone mass and increased osteoclast number. Importantly, hemolytic disease patients exhibited decreased serum level of Hp as well as low bone mineral density. Taken together, this study suggests that Zscan10 negatively regulates osteoclast differentiation through transcription of Hp.

Silencing of ECHDC1 inhibits growth of gemcitabine-resistant bladder cancer cells.

Combined gemcitabine and cisplatin (GC) treatment is a first line chemotherapy for bladder cancer. However, acquired resistance to GC has been a major problem. To address the mechanism of gemcitabine resistance, and to identify potential biomarkers or target proteins for its therapy, we aimed to identify candidate proteins associated with gemcitabine resistance using proteomic analysis. We established gemcitabine-resistant human bladder cancer cell lines (UMUC3GR and HT1376GR) from gemcitabine-sensitive human bladder cancer cell lines (UMUC3 and HT1376). We compared the protein expression of parental and gemcitabine-resistant cell lines using isobaric tags for relative and absolute quantification (iTRAQ) and liquid chromatography tandem mass spectrometry. Among the identified proteins, ethylmalonyl-CoA decarboxylase (ECHDC1) expression was significantly increased in both of the gemcitabine-resistant cell lines compared to the respective parental cell lines. Silencing of ECHDC1 reduced ECHDC1 expression and significantly inhibited the proliferation of UMUC3GR cells. Furthermore, silencing of ECHDC1 induced upregulation of p27, which is critical for cell cycle arrest in the G1 phase, and induced G1 arrest. In conclusion, ECHDC1 expression is increased in gemcitabine-resistant bladder cancer cells, and is involved in their cell growth. ECHDC1, which is a metabolite proofreading enzyme, may be a novel potential target for gemcitabine-resistant bladder cancer therapy.