Development of a novel treatment based on PKMYT1 inhibition for cisplatin-resistant bladder cancer with miR-424-5p-dependent cyclin E1 amplification.

BACKGROUND: Chemotherapy including cisplatin is recommended for the treatment of advanced bladder cancer, but its effectiveness is limited due to the acquisition of drug resistance. Although several mechanisms of cisplatin resistance have been reported, there are still many unknowns, and treatment of cisplatin-resistant bladder cancer remains difficult. Accordingly, in this study, we aimed to identify and characterize microRNAs involved in cisplatin resistance. METHODS: Small RNA sequencing analysis was performed to search for microRNAs related to cisplatin resistance. The identified microRNAs were then characterized using gain-of-function studies, sensitivity analysis, target gene analysis, and cellular assays. RESULTS: We identified miR-424-5p as a candidate microRNA that was downregulated in cisplatin-resistant strains compared with parental strains. Notably, in gain-of-function studies, miR-424-5p suppressed the proliferative ability of cisplatin-resistant bladder cancer (CDDP-R BC). Furthermore, miR-424-5p restored sensitivity to cisplatin. RNA sequence analysis revealed seven candidate genes targeted by this microRNA. Among them, cyclin E1 (CCNE1) was chosen for subsequent analyses because its expression was upregulated in cisplatin-resistant cells compared with parental cells and because recent studies have shown that CCNE1 amplification is synthetic lethal with PKMYT1 kinase inhibition. Therefore, we performed functional analysis using the PKMYT1 inhibitor RP-6306 and demonstrated that RP-6306 inhibited cell growth through suppression of mitotic entry and restored cisplatin sensitivity in CDDP-R BC. CONCLUSIONS: Overall, our findings provided insights into the development of novel therapeutic strategies for CDDP-R BC.

Assessing antiviral treatment efficacy and risk factors for severe COVID-19 in kidney transplant recipients during the Omicron subvariant-dominant period: a retrospective study.

BACKGROUND: Kidney transplant recipients (KTRs) are at risk of severe coronavirus disease 2019 (COVID-19), and even now that Omicron subvariants have become dominant, cases of severe disease are certain to occur. The aims of this retrospective study were to evaluate the efficacy of antiviral treatment for COVID-19 and to identify risk factors for severe disease in KTRs during Omicron subvariant-dominant periods. METHODS: A total of 65 KTRs diagnosed with COVID-19 who received antiviral treatment between July 2022 and September 2023 were analyzed. Mild cases received oral molnupiravir (MP) as outpatient therapy, while moderate or worse cases received intravenous remdesivir (RDV) as inpatient therapy. In principle, mycophenolate mofetil was withdrawn and switched to everolimus. We investigated the efficacy of antiviral treatment and compared the clinical parameters of mild/moderate and severe/critical cases to identify risk factors for severe COVID-19. RESULTS: Among 65 cases, 49 were mild, 6 were moderate, 9 were severe, and 1 was of critical severity. MP was administered to 57 cases; 49 (86%) improved and 8 (14%) progressed. RDV was administered to 16 cases; 14 (87%) improved and 2 (13%) progressed. Seventeen (26%) cases required hospitalization, and none died. Comparisons of the severe/critical group (n = 10) with the mild/moderate group (n = 55) demonstrated that the severe/critical group had a significantly higher median age (64 vs. 53 years, respectively; p = 0.0252), prevalence of diabetes (70% vs. 22%, respectively; p = 0.0047) and overweight/obesity (40% vs. 11%, respectively; p = 0.0393), as well as a significantly longer median time from symptom onset to initial antiviral therapy (3 days vs. 1 day, respectively; p = 0.0026). Multivariate analysis showed that a longer time from symptom onset to initial antiviral treatment was an independent risk factor for severe COVID-19 (p = 0.0196, odds ratio 1.625, 95% confidence interval 1.081-2.441). CONCLUSION: These findings suggest that a longer time from symptom onset to initial antiviral treatment is associated with a higher risk of severe COVID-19 in KTRs. Initiating antiviral treatment as early as possible is crucial for preventing severe outcomes; this represents a valuable insight into COVID-19 management in KTRs.

LncRNA BCYRN1 as a Potential Therapeutic Target and Diagnostic Marker in Serum Exosomes in Bladder Cancer.

Bladder cancer (BC) is a common genitourinary malignancy that exhibits silent morbidity and high mortality rates because of a lack of diagnostic markers and limited effective treatments. Here, we evaluated the role of the lncRNA brain cytoplasmic RNA 1 (BCYRN1) in BC. We performed loss-of-function assays to examine the effects of BCYRN1 downregulation in T24 and BOY BC cells. We found that BCYRN1 downregulation significantly inhibited the proliferation, migration, invasion, and three-dimensional spheroid formation ability and induced apoptosis in BC cells. Additionally, gene set enrichment analysis (GSEA) using RNA sequences from tumor fractions showed that BCYRN1 downregulation decreased the expression of mRNAs associated with the cell cycle. These findings were supported by observations of G2/M arrest in flow cytometry assays. Finally, we examined the expression of serum exosomal BCYRN1 as a biomarker. Clinically, BCYRN1 expression in serum exosomes from patients with BC (n = 31) was significantly higher than that in healthy donors (n = 19; mean difference: 4.1-fold higher, p < 0.01). Moreover, in patients who had undergone complete resection of BC, serum exosomal BCYRN1 levels were significantly decreased (n = 8). Thus, serum exosomal BCYRN1 may be a promising diagnostic marker and therapeutic target in patients with BC.

Potential therapeutic target secretogranin II might cooperate with hypoxia-inducible factor 1α in sunitinib-resistant renal cell carcinoma.

Multitargeted receptor tyrosine kinase inhibitors, including vascular endothelial growth factor (VEGF) inhibitors, such as sunitinib, have been used as the primary targeted agents for patients with recurrent or distant metastasis of advanced renal cell carcinoma (RCC). However, endogenous or acquired sunitinib resistance has become a significant therapeutic problem. Therefore, we focused on mechanisms of sunitinib resistance in RCC. First, we undertook RNA sequencing analysis using previously established sunitinib-resistant RCC (SUR-Caki1, SUR-ACHN, and SUR-A498) cells. The results showed increased expression of secretogranin II (SCG2, chromogranin C) in SUR-RCC cells compared to parental cells. The Cancer Genome Atlas database showed that SCG2 expression was increased in RCC compared to normal renal cells. In addition, the survival rate of the SCG2 high-expression group was significantly lower than that of the RCC low-expression group. Thus, we investigated the involvement of SCG2 in sunitinib-resistant RCC. In vitro analysis showed that migratory and invasive abilities were suppressed by SCG2 knockdown SUR cells. As SCG2 was previously reported to be associated with angiogenesis, we undertook a tube formation assay. The results showed that suppression of SCG2 inhibited angiogenesis. Furthermore, coimmunoprecipitation assays revealed a direct interaction between SCG2 and hypoxia-inducible factor 1α (HIF1α). Expression levels of VEGF-A and VEGF-C downstream of HIF1α were found to be decreased in SCG2 knockdown SUR cells. In conclusion, SCG2 could be associated with sunitinib resistance through VEGF regulation in RCC cells. These findings could lead to a better understanding of the VHL/HIF/VEGF pathway and the development of new therapeutic strategies for sunitinib-resistant RCC.

Acute kidney injury caused by systemic Neisseria gonorrhoeae infection after successful kidney transplantation.

Neisseria gonorrhoeae is one of the microbes that can causes male urethritis. This microbe is most likely to be transmitted via sexual intercourse. In men, the representative infection sites are the urethra, and oral mucosa but gonococcemia is rere. We present a case of gonococcemia in a 47-year-old male successful kidney recipient. He temporarily lost his graft function due to acute kidney injury followed by sepsis; however, short-course intermittent hemodialysis and long-term intensive ceftriaxone inoculation saved his life and his graft function.

Long-term desensitization for ABO-incompatible living related kidney transplantation recipients with high refractory and rebound anti-blood type antibody: case report.

BACKGROUND: ABO-incompatible living related kidney transplantation (ABO-iLKT) has increased the possibilities for kidney transplantation in patients with end stage renal disease. Due to advancements in immunosuppressive agents and the identification of immunological conditions following ABO-iLKT, this transplantation technique has achieved the same success rate as ABO-compatible LKT. However, some patients continue to generate anti-blood type antibodies, despite conventional immunosuppressant treatment. CASE PRESENTATION: A 60-year-old man was referred to our hospital for kidney transplantation. The proposed transplant was ABO incompatible, from a donor with blood-type A to a recipient with blood-type O. The recipient's anti-A blood-type IgG antibody titer was measured at 4096-fold dilution. Following desensitization therapy, including mycophenolate mofetil (MMF) 750 mg/day for 3 months, intravenous Rituximab 200 mg, and two sessions of double filtration plasmapheresis, the anti-A blood-type IgG antibody titer decreased to only 516-fold dilution and did not meet our target of less than 128-fold dilution. MMF was thus continued for an additional 4 months and four additional sessions of plasmapheresis were undertaken. Following these interventions, antibody titers decreased to 128-fold dilution and ABO-iLKT was performed. Following transplant, antibody-mediated rejection was not observed and renal function was preserved. However, a post-operative renal biopsy 1.5 months later showed evidence of T-cell-mediated rejection IB. The patient was treated with steroids, with no increase in serum creatinine. CONCLUSION: Our findings suggest that the long-term single MMF desensitization therapy could be a suitable option for ABO-iLKT with high refractory and rebound anti-blood type antibody. Further studies are required to establish the optimal immunosuppression regimen to control B cell- mediated immunity in ABO-iLKT.

Targeting metabolic reprogramming to overcome drug resistance in advanced bladder cancer: insights from gemcitabine- and cisplatin-resistant models.

Gemcitabine plus cisplatin (GC) combination chemotherapy is the primary treatment for advanced bladder cancer (BC) with unresectable or metastatic disease. However, most cases develop resistance to this therapy. We investigated whether drug resistance could be targeted through metabolic reprogramming therapies. Metabolomics analyses in our lab's gemcitabine- and cisplatin-resistant cell lines revealed increased phosphoglycerate dehydrogenase (PHGDH) expression in gemcitabine-resistant cells compared with parental cells. Isocitrate dehydrogenase 2 (IDH2) gain of function stabilized hypoxia-inducible factor1α (HIF1α) expression, stimulating aerobic glycolysis. In gemcitabine-resistant cells, elevated fumaric acid suppressed prolyl hydroxylase domain-containing protein 2/Egl nine homolog 1 (PHD2) and stabilized HIF1α expression. PHGDH downregulation or inhibition in gemcitabine-resistant BC cells inhibited their proliferation, migration, and invasion. Cisplatin-resistant cells showed elevated fatty acid metabolism, upregulating fatty acid synthase (FASN) downstream of tyrosine kinase. Using the fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor erdafitinib, we inhibited malonyl-CoA production, which is crucial for fatty acid synthesis, and thereby suppressed upregulated HIF1α expression. Combination treatment with NCT503 and erdafitinib synergistically suppressed tumor cell proliferation and induced apoptosis in vitro and in vivo. Understanding these mechanisms could enable innovative BC therapeutic strategies to be developed.

Inguinal Lymphadenopathy After Renal Transplantation Leading to the Diagnosis of Prostate Cancer: A Case Report.

It is extremely rare for a patient with prostate cancer (PCa) to have palpable lymph nodes at the initial presentation. In fact, only 4 case reports of palpable superficial lymph nodes at the first visit led to the diagnosis of PCa. Moreover, no such cases are reported in kidney transplantation (KT) patients. A 72-year-old man who started hemodialysis due to diabetic nephropathy was referred to our hospital for a KT in 2018. Before the KT, he had a negative screen for cancer, including PCa. The postoperative course was good. He felt a lump in the left inguinal region three years after the KT. A computed tomography scan revealed abdominal and left inguinal lymphadenopathy, which was consistent with a post-transplant lymphoproliferative disorder. However, a biopsy of an inguinal lymph node revealed adenocarcinoma with positive prostate-specific antigen (PSA) staining, suggesting lymph node metastasis of PCa. The blood PSA level was 1674.23 ng/mL. A prostate biopsy was performed, the pathologic diagnosis of which was PCa, with a Gleason score of 10. In conclusion, even though the standardized incidence ratio of PCa is not known to increase in KT patients, PCa should be included in the differential diagnosis, along with the possibility of post-transplant lymphoproliferative disorder. We also suggest the importance of regular screening for malignant tumors after organ transplantation.

Low dose tacrolimus exposure and early steroid withdrawal with strict body weight control can improve post kidney transplant glucose tolerance in Japanese patients.

The development of diabetes mellitus (DM) after living donor kidney transplantation (KT) is a risk factor for worsening transplant kidney function, cardiac disease, and cerebrovascular disease, which may affect prognosis after KT. At our institution, all patients' glucose tolerance is evaluated perioperatively by oral glucose tolerance tests (OGTTs) at pre-KT, and 3, 6, and 12 month (mo.) after KT. We analyzed the insulinogenic index (ISI) and homeostasis model assessment beta cell (HOMA-ß) based on the immunoreactive insulin (IRI) levels to determine how glucose tolerance changed after KT in 214 patients who had not been diagnosed with DM before KT. In addition, we analyzed the body mass index (BMI) which may also influence glucose tolerance after KT. The concentration of tacrolimus (TAC) in blood was also measured as the area under the curve (AUC) to examine its effects at each sampling point. The preoperative-OGTTs showed that DM was newly diagnosed in 22 of 214 patients (10.3%) who had not been given a diagnosis of DM by the pre-KT fasting blood sugar (FBS) tests. The glucose tolerance was improved in 15 of 22 DM patients at 12 mo. after KT. ISI and IRI deteriorated only at 3 mo. after KT but improved over time. There was a trend of an inverse correlation between HOMA-ß and TAC-AUC. We also found inverse correlations between IRI and an increase in BMI from 3 to 12 mo. after KT. Early corticosteroid withdrawal or the steroid minimization protocol with tacrolimus to maintain a low level of diabetogenic tacrolimus and BMI decrease after KT used by our hospital individualizes lifestyle interventions for each patient might contribute to an improvement in post-KT glucose tolerance.

Laparoscopic Surgery for Pheochromocytoma in Hemodialysis Patients.

Objectives: We analyzed the clinical outcomes of laparoscopic adrenalectomy for pheochromocytomas in hemodialysis compared with nonhemodialysis patients. Methods: Fifty-seven patients (7 hemodialysis and 50 nonhemodialysis) were included in the study. We analyzed the differences in clinical parameters and outcomes between the hemodialysis patient groups and nonhemodialysis patient groups as well as identified predictors for an intraoperative hypertensive spike. Results: The increasing intravascular volume before surgery in hemodialysis patients made perioperative hemodynamic management safer. No significant difference in clinical parameters between the two groups was observed except for the length of hospitalization that was significantly longer in the hemodialysis patients (9 vs. 6 days, P=0.005). An increase in systolic blood pressure at CO2 insufflation was an independent predictor of a hypertensive spike with a cutoff value of 22.5 mmHg (odds ratio 1.038, 95% confidence interval 1.012-1.078). Conclusion: Laparoscopic adrenalectomy for pheochromocytomas in hemodialysis was safe and feasible. An increase in systolic blood pressure at CO2 insufflation was a predictor of the intraoperative hypertensive spike. The research in this manuscript is not registered. This is a retrospective study.

Long-Term Outcome of ABO-Incompatible Kidney Transplantation in Patients Treated With Low-Dose Rituximab Regimen.

BACKGROUND: Introduction of rituximab in the desensitization protocols for ABO-incompatible (ABOI) kidney transplantation (KTX) has afforded excellent results. However, the acceptability of minimal dosage of rituximab in these protocols remains to be defined. METHODS: Sixty-three patients who underwent ABOI KTX were included in this study. The desensitization protocol consisted of plasmapheresis, tacrolimus, mycophenolate mofetil, methylprednisolone, intravenous immunoglobulin, basiliximab, and low-dose rituximab (100 mg/body). We evaluated the efficacy, safety, and long-term outcome of this protocol (group R, n = 39) and compared them with those of patients who underwent splenectomy (group S, n = 24). RESULTS: Graft and patient survival at 10 years after KTX were comparable between the groups (94.4% [group R] vs 95.4% [group S] and 94.6% [group R] vs 95.8% [group S], respectively). The incidence of acute antibody-mediated rejection (AAMR) was similar in the 2 groups (10.2% vs 12.5%). There were no significant differences in the incidence of chronic active antibody-mediated rejection. Of the patients, 7 developed AAMR and 3 of these patients (1 in group R and 2 in group S) lost their grafts. There were no significant differences in the incidence of chronic active antibody-mediated rejection. The incidence of postoperative cytomegalovirus infection in group R was significantly lower than that in group S. Furthermore, the incidence of postoperative late-onset neutropenia was low in group R. CONCLUSIONS: A low-dose rituximab regimen for ABOI KTX is acceptable for preventing AAMR with a low incidence of delayed adverse events.

A case of latent heterozygous Fabry disease in a female living kidney donor candidate.

A 52-year-old woman had been found to have hematuria at her annual checkup 5 years in a row. She hoped to donate her kidney to her husband, so we performed a percutaneous kidney biopsy at our department. It was difficult for us to detect apparent abnormalities under a light microscopic examination, and she was determined to meet the eligibility criteria for living kidney transplantation. However, the sample for electron microscopy was not evaluated before kidney donation. She subsequently underwent living kidney transplantation as a donor. A 1-h biopsy revealed swelling and obvious vacuolation of the glomerular podocytes, which were characteristic of Fabry disease. Her medical history and examinations were reviewed. No findings or episodes were observed. Pre-donation electronmicroscopy revealed numerous zebra bodies in the podocytes. A definite diagnosis of heterozygous Fabry disease was made based on the GLA gene mutation despite the normal range of leukocyte α-Gal A activity. Based on the pathological deposition of GL-3, chaperone therapy was initiated to suppress the progression of organ damage. In this case, we could not confirm a diagnosis of Fabry disease despite performing a renal biopsy prior to kidney donation. Kidney donor candidates may sometimes have factors that cannot be assumed based on medical or family history. Thus, it is important to perform a renal biopsy before kidney donation when necessary, and to always conduct a detailed evaluation including electron microscopy.

Preceding T-Cell-Mediated Rejection Is Associated with the Development of Chronic Active Antibody-Mediated Rejection by de Novo Donor-Specific Antibody.

AIM: Chronic active antibody-mediated rejection (CAABMR) is an important cause of late-stage renal allograft loss. Early inflammatory events such as acute rejection and infection after transplantation are considered to be the risk factors of de novo donor-specific antibody (dnDSA) production. In this study, we investigated the relationship between pre-disposing T-cell-mediated rejection and dnDSA-positive CAABMR. METHODS: We recruited 365 patients who underwent ABO-compatible renal transplantation at our hospital. Among them, 16 patients diagnosed as having dnDSA-positive CAABMR were designated as a CAABMR group, and 38 randomly selected patients were designated as a control group. All biopsies from 1 month after transplantation were included in the study. The presence or absence of borderline changes (BLCs), acute T-cell-mediated rejection (ATMR), microvascular inflammation (MVI), and C4d positive on peritubular capillaries (C4d-P) was examined. RESULTS: In the CAABMR group, BLC/ATMR was found in 12 cases (75%), and the mean duration until appearance of BLC/ATMR was 282.7 ± 328.7 days. C4d-P was found in 11 cases (68.8%), and the mean duration until its appearance was 1,432 ± 1,307 days. MVI was found in all cases, and the mean duration until its appearance was 1,333 ± 1,126 days. The mean duration until diagnosis of CAABMR was 2,268 ± 1,191 days. In the control group, BLC/ATMR was found in 13 cases (34.2%), and the mean duration until the appearance of BLC/ATMR was 173.1 ± 170.4 days. C4d-P was found in 2 cases (5.3%), and the durations until its appearance were 748 and 1,881 days. No cases of MVI were found in the control group. The frequency of BLC/ATMR was significantly higher in the CAABMR group (p < 0.01). CONCLUSION: Preceding BLC/ATMR is associated with the development of CAABMR with dnDSA.

Successful Kidney Transplantation Alone With Severe Left Ventricular Systolic Dysfunction of Ejection Fraction 14%: A Case Report.

It is well known that correction of uremia by kidney transplantation alone (KTA) improves left ventricular systolic dysfunction (LVSD). However, for kidney transplant candidates with extremely severe LVSD, KTA is considered to be contraindicated because of the high risk of peri-operative management. We report a case of successful kidney transplantation with severe LVSD with an ejection fraction (EF) of 14% and low systolic blood pressure (SBP) of approximately 65 to 80 mm Hg. In this case, in spite of an extremely low EF and SBP, functional capacity was assessed using metabolic equivalents (METs) and showed a level of almost 4. The operation was performed carefully, considering the cardiac, operative, and anesthetic risks. No surgical complications occurred, and the patient received intensive care during the peri-operative period. His postoperative course was almost favorable, and he was discharged on postoperative day 29. The present report concludes that evaluation of METs may expand the indication for KTA in patients with extremely severe LVSD.

Kidney transplantation with concomitant simple nephrectomy by thoracoabdominal approach for patients with huge autosomal dominant polycystic kidney disease (ADPKD): A case report.

Autosomal dominant polycystic kidney disease (ADPKD) is a common inherited kidney disease with growing multiple cyst formation. We report here a huge ADPKD case of kidney transplantation concomitant with simple nephrectomy through thoracoabdominal approach that allows surgeons to manipulate the renal vessels, the adrenal grand, the trigonal ligament, and the lower pole of the kidney under the wide operative field. Because of the direct recognition of the surgical anatomy, it might be safe and feasible for simple nephrectomy in huge ADPKD patients undergoing concomitant kidney transplantation despite of the wide skin incision required by this approach.