SPRTN metalloprotease participates in repair of ROS-mediated DNA-protein crosslinks.

Exposure to reactive oxygen species (ROS) can induce DNA-protein crosslinks (DPCs), unusually bulky DNA lesions that block replication and transcription and play a role in aging, cancer, cardiovascular disease, and neurodegenerative disorders. Repair of DPCs depends on the coordinated efforts of proteases and DNA repair enzymes to cleave the protein component of the lesion to smaller DNA-peptide crosslinks which can be processed by tyrosyl-DNA phosphodiesterases 1 and 2, nucleotide excision and homologous recombination repair pathways. DNA-dependent metalloprotease SPRTN plays a role in DPC repair, and SPRTN-deficient mice exhibit an accelerated aging phenotype and develop liver cancer early in life.

Frailty in kidney transplant recipients.

Kidney transplantation is the treatment of choice even for the elderly, as it improves quality of life and life expectancy, lowering the financial burden to the health care system compared to dialysis therapy. In Japan, kidney transplant recipients have become older due to the shift in demographics. Compared to community-dwelling elderly adults, elderly kidney transplant recipients undergoing immunosuppressive therapy have a higher risk of age-related outcomes including hospital readmissions, infections, dementia, malignancies, and fractures.

Comparison of Oncological Outcomes between Transperitoneal and Retroperitoneal Approaches in Laparoscopic Nephroureterectomies for Upper Tract Urothelial Carcinoma.

: Our aim was to clarify the oncological outcomes of the two different approaches to laparoscopic nephroureterectomies (LNUs) in Japan, and to examine whether there were any significant differences between the transperitoneal approach and the retroperitoneal approach. : We retrospectively evaluated patients who underwent an LNU for upper tract urothelial carcinoma (UTUC) from January 2013 to December 2022. We identified 52 patients who underwent a transperitoneal LNU (tLNU) and 93 who underwent a retroperitoneal LNU (rLNU).

Experience with Tandem Pre-Dilution Online Hemodiafiltration and Centrifugal Plasma Exchange in Pretransplant Desensitization for Abo-Incompatible Kidney Transplantation: A Case Report.

Background: In the use of therapeutic plasma exchange (TPE) as antibody removal therapy for ABO-incompatible (ABOi) kidney transplantation, it is technically possible to perform online hemodiafiltration (OHDF) and TPE simultaneously for patients who are receiving OHDF. In this study, we report tandem therapy of pre-dilution OHDF and centrifugal plasma exchange (cTPE), instead of membrane plasma exchange, which is the mainstay of TPE in Japan.

Methods: A total of 14 sessions of tandem cTPE and pre-dilution OHDF were performed as preoperative antibody removal therapy for 6 ABOi kidney transplant recipients.

Dimerization-dependent serine protease activity of FAM111A prevents replication fork stalling at topoisomerase 1 cleavage complexes.

FAM111A, a serine protease, plays roles in DNA replication and antiviral defense. Missense mutations in the catalytic domain cause hyper-autocleavage and are associated with genetic disorders with developmental defects. Despite the enzyme's biological significance, the molecular architecture of the FAM111A serine protease domain (SPD) is unknown.

A Case of Bariatric Surgery for a Japanese Kidney Transplant Recipient With Diabetes Mellitus: A Case Report.

The patient, a 54-year-old woman, underwent a living donor kidney transplant at Osaka City University Hospital 7 years before the bariatric surgery. Her comorbidities were diabetes, sleep apnea, and severe obesity (weight 103 kg, body mass index [BMI] 36 kg/m), and her diabetes was poorly controlled with an HbA1c of 8.5%.

Frailty and sarcopenia in older kidney transplant recipients: a cross-sectional study.

Purpose: The aging of the kidney transplant population is accelerating, and measures against geriatric syndromes including frailty and sarcopenia, which elevate the risk of needing long-term care and even death, are being considered important. Recently, both the frailty and sarcopenia criteria for Asians were revised based on various research reports and clinical experiences. The purpose of this study is twofold: firstly, to investigate the prevalence of frailty based on the revised Japanese version of the Cardiovascular Health Study (J-CHS) criteria and the Kihon Checklist (KCL) and that of sarcopenia based on the Asian Working Group for Sarcopenia (AWGS) 2019 as well as the relationship between frailty and sarcopenia, and secondly, to determine the concurrent validity of the KCL with the revised J-CHScriteria in older kidney transplant recipients.

Novel Technique for Hand-Assisted Laparoscopic Nephrectomy for Advanced Renal Cell Carcinoma with Renal Vein and Inferior Vena Cava Thrombi: Three Case Reports.

Introduction: The treatment of thrombi in the renal vein (RV) and inferior vena cava (IVC) requires advanced laparoscopic experience. We present three cases of hand-assisted laparoscopic nephrectomy (HALN) using a novel technique for treating advanced renal cell carcinoma (RCC) with thrombi in the RV and IVC. .

Functions and evolution of FAM111 serine proteases.

Proteolysis plays fundamental and regulatory roles in diverse cellular processes. The serine protease FAM111A (FAM111 trypsin-like peptidase A) emerged recently as a protease involved in two seemingly distinct processes: DNA replication and antiviral defense. FAM111A localizes to nascent DNA and plays a role at the DNA replication fork.

Laparoscopic ureteroneocystostomy for iatrogenic ureterovaginal fistula after modified radical hysterectomy: A case report.

An unique laparoscopic ureteroneocystostomy technique was performed to treat an iatrogenic ureterovaginal fistula that was formed in a 69-year-old woman following open modified radical hysterectomy for endometrial cancer. Severe adhesions between the distal ureter and the surrounding tissues, including the iliac artery, were observed. Owing to difficulties in identifying the distal ureter, the proximal ureter was identified and dissected downward to free the ureter, thereby allowing anastomosis.

Intra-S phase checkpoint kinase Chk1 dissociates replication proteins Treslin and TopBP1 through multiple mechanisms during replication stress.

Replication stress impedes DNA polymerase progression causing activation of the ataxia telangiectasia and Rad3-related signaling pathway, which promotes the intra-S phase checkpoint activity through phosphorylation of checkpoint kinase 1 (Chk1). Chk1 suppresses replication origin firing, in part, by disrupting the interaction between the preinitiation complex components Treslin and TopBP1, an interaction that is mediated by TopBP1 BRCT domain-binding to two cyclin-dependent kinase (CDK) phosphorylation sites, T968 and S1000, in Treslin. Two nonexclusive models for how Chk1 regulates the Treslin-TopBP1 interaction have been proposed in the literature: in one model, these proteins dissociate due to a Chk1-induced decrease in CDK activity that reduces phosphorylation of the Treslin sites that bind TopBP1 and in the second model, Chk1 directly phosphorylates Treslin, resulting in dissociation of TopBP1.

MYC regulates ribosome biogenesis and mitochondrial gene expression programs through its interaction with host cell factor-1.

The oncoprotein transcription factor MYC is a major driver of malignancy and a highly validated but challenging target for the development of anticancer therapies. Novel strategies to inhibit MYC may come from understanding the co-factors it uses to drive pro-tumorigenic gene expression programs, providing their role in MYC activity is understood. Here we interrogate how one MYC co-factor, host cell factor (HCF)-1, contributes to MYC activity in a human Burkitt lymphoma setting.

Tandem Deubiquitination and Acetylation of SPRTN Promotes DNA-Protein Crosslink Repair and Protects against Aging.

DNA-protein crosslinks (DPCs) are highly toxic DNA lesions that threaten genomic integrity. Recent findings highlight that SPRTN, a specialized DNA-dependent metalloprotease, is a central player in proteolytic cleavage of DPCs. Previous studies suggest that SPRTN deubiquitination is important for its chromatin association and activation.

DNA-protein crosslinks from environmental exposure: Mechanisms of formation and repair.

Many environmental carcinogens cause DNA damage, which can result in mutations and other alterations in genomic DNA if not repaired promptly. Because of the bulkiness of the lesions, DNA-protein crosslinks (DPCs) are one of the types of toxic DNA damage with potentially deleterious consequences. Despite the importance of DPCs, how cells remove these complex DNA adducts has been incompletely understood.

FAM111A protects replication forks from protein obstacles via its trypsin-like domain.

Persistent protein obstacles on genomic DNA, such as DNA-protein crosslinks (DPCs) and tight nucleoprotein complexes, can block replication forks. DPCs can be removed by the proteolytic activities of the metalloprotease SPRTN or the proteasome in a replication-coupled manner; however, additional proteolytic mechanisms may exist to cope with the diversity of protein obstacles. Here, we show that FAM111A, a PCNA-interacting protein, plays an important role in mitigating the effect of protein obstacles on replication forks.

Enzalutamide versus flutamide for castration-resistant prostate cancer after combined androgen blockade therapy with bicalutamide: the OCUU-CRPC study.

Background: Before the androgen target therapy era, flutamide was widely used for castration-resistant prostate cancer in Japan. Enzalutamide is currently the recommended treatment; however, the efficacy and safety of enzalutamide and flutamide after combined androgen blockade therapy with bicalutamide, has not been compared.

Methods: Patients with castration-resistant prostate cancer who received combined androgen blockade therapy with bicalutamide were randomly assigned to receive either enzalutamide or flutamide.

Tyrosine Phosphorylation of Mitochondrial Creatine Kinase 1 Enhances a Druggable Tumor Energy Shuttle Pathway.

How mitochondrial metabolism is altered by oncogenic tyrosine kinases to promote tumor growth is incompletely understood. Here, we show that oncogenic HER2 tyrosine kinase signaling induces phosphorylation of mitochondrial creatine kinase 1 (MtCK1) on tyrosine 153 (Y153) in an ABL-dependent manner in breast cancer cells. Y153 phosphorylation, which is commonly upregulated in HER2 breast cancers, stabilizes MtCK1 to increase the phosphocreatine energy shuttle and promote proliferation.

Spartan deficiency causes accumulation of Topoisomerase 1 cleavage complexes and tumorigenesis.

Germline mutations in SPRTN cause Ruijs-Aalfs syndrome (RJALS), a disorder characterized by genome instability, progeria and early onset hepatocellular carcinoma. Spartan, the protein encoded by SPRTN, is a nuclear metalloprotease that is involved in the repair of DNA-protein crosslinks (DPCs). Although Sprtn hypomorphic mice recapitulate key progeroid phenotypes of RJALS, whether this model expressing low amounts of Spartan is prone to DPC repair defects and spontaneous tumors is unknown.

Spartan deficiency causes genomic instability and progeroid phenotypes.

Spartan (also known as DVC1 and C1orf124) is a PCNA-interacting protein implicated in translesion synthesis, a DNA damage tolerance process that allows the DNA replication machinery to replicate past nucleotide lesions. However, the physiological relevance of Spartan has not been established. Here we report that Spartan insufficiency in mice causes chromosomal instability, cellular senescence and early onset of age-related phenotypes.

BRCA1-associated protein 1 (BAP1) deubiquitinase antagonizes the ubiquitin-mediated activation of FoxK2 target genes.

BRCA1-associated protein 1 (BAP1), which is frequently mutated in cancer, functions as a deubiquitinase (DUB) for histone H2A. Although BAP1 interacts with a transcriptional regulator, HCF-1, and transcription factors FoxK1 and FoxK2, how BAP1 controls gene expression remains unclear. This study investigates the importance of BAP1 DUB activity and the interactions with FoxK2 and HCF-1 in the regulation of FoxK2 target genes.

A Case of Pulmonary Pleomorphic Carcinoma With Renal Metastasis.

A 62-year-old man was referred to our hospital for an axillary mass. Computed tomography (CT) revealed a right axillary tumor and a left renal tumor. Needle biopsies of lung tumor and renal tumor were performed, but a definite diagnosis was impossible.