Ovarian high-grade serous carcinoma cells with low SMARCA4 expression and high SMARCA2 expression contribute to platinum resistance.

Platinum resistance is a major obstacle to the treatment of ovarian cancer and is correlated with poor clinical outcomes. Intratumor heterogeneity plays a key role in chemoresistance. Recent studies have emphasized the contributions of genetic and epigenetic factors to the development of intratumor heterogeneity. Although the clinical significance of multi-subunit chromatin remodeler, switch/sucrose nonfermenting (SWI/SNF) complexes in cancers has been reported, the impacts of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4/subfamily A, member 2 (SMARCA4/A2) expression patterns in human cancer tissues have not been fully elucidated. Here, we show that low expression of SMARCA4 and high expression of SMARCA2 are associated with platinum resistance in ovarian high-grade serous carcinoma (HGSC) cells. We used fluorescence multiplex immunohistochemistry (fmIHC) to study resected specimens; we examined heterogeneity in human HGSC tissues at the single-cell level, which revealed that the proportion of cells with the SMARCA4low /SMARCA2high phenotype was positively correlated with clinical platinum-resistant recurrence. We used stable transfection of SMARCA2 and siRNA knockdown of SMARCA4 to generate HGSC cells with the SMARCA4low /SMARCA2high phenotype; these cells had the greatest resistance to carboplatin. Bioinformatics analyses revealed that the underlying mechanism involved in substantial alterations to chromatin accessibility and resultant fibroblast growth factor (FGF) signaling activation, MAPK pathway activation, BCL2 overexpression, and reduced carboplatin-induced apoptosis; these were confirmed by in vitro functional experiments. Furthermore, in vivo experiments in an animal model demonstrated that combination therapy with carboplatin and a fibroblast growth factor receptor (FGFR) inhibitor promoted cell death in HGSC xenografts. Taken together, these observations reveal a specific subpopulation of HGSC cells that is associated with clinical chemoresistance, which may lead to the establishment of a histopathological prediction system for carboplatin response. Our findings may facilitate the development of novel therapeutic strategies for platinum-resistant HGSC cells. © 2023 The Pathological Society of Great Britain and Ireland.

Essential Roles of TDO2 in Gastric Cancer: TDO2 Is Associated with Cancer Progression, Patient Survival, PD-L1 Expression, and Cancer Stem Cells.

INTRODUCTION: Tryptophan metabolism has been shown to be involved in tumor development. Two main tryptophan-degrading enzymes, tryptophan 2,3-dioxygenase (TDO2) and indoleamine 2,3-dioxygenase 1 (IDO1), may potently promote cancer cell survival and distant metastasis in diverse types of cancer, such as lung and breast cancer. IDO1 overexpression is an independent prognosticator in gastric cancer (GC). This work aimed to uncover the expression of TDO2 and its clinicopathologic significance in GC. METHODS: TDO2 expression was evaluated in public data of The Cancer Genome Atlas cohort STAD and in two different GC cohorts. Correlation between TDO2 and immune cell infiltrates as well as PD-L1 tumor staining was investigated. The biofunction of TDO2 was examined with MTT, colony formation, and spheroid formation assays by RNA interference. RESULTS: TDO2 expression was correlated with both progressive disease and clinical outcome, and its expression was an independent predictor of prognosis in GC. TDO2 expression was correlated with infiltration of immune cells and tumor expression of PD-L1. Inhibition of TDO2 expression suppressed cell proliferation, colony formation, and cell invasion of GC cells. Additionally, suppression of TDO2 expression inhibited spheroid body-formation and viability of GC organoids. CONCLUSION: Our data show that TDO2 might be a crucial marker for predicting prognosis and targeted therapy in GC.

Prognostic impact of Schlafen 11 in bladder cancer patients treated with platinum-based chemotherapy.

The utility of Schlafen 11 (SLFN11) expression as a predictive biomarker for platinum-based chemotherapy has been established for cancers from different histologies. However, the therapeutic relevance of SLFN11 in bladder cancer (BC) is unknown. Here, we examined the clinicopathologic significance of SLFN11 expression across 120 BC cases by immunohistochemistry. We divided the cases into two cohorts, one including 50 patients who received adjuvant or neoadjuvant platinum-based chemotherapy, and the other including 70 BC patients treated by surgical resection without chemotherapy. In the cohort of 50 BC cases treated with platinum-based chemotherapy, the SLFN11-positive group (n = 25) showed significantly better overall survival than the SLFN11-negative group (n = 25, P = .012). Schlafen 11 expression correlated significantly with the expression of luminal subtype marker GATA3. Multivariate analyses identified SLFN11 expression as an independent prognostic predictor (odds ratio, 0.32; 95% confidence interval, 0.11-0.91; P = .033). Conversely, in the cohort of 70 BC cases not receiving platinum-based chemotherapy, the SLFN11-positive group (n = 29) showed significantly worse overall survival than the SLFN11-negative group (n = 41, P = .034). In vitro analyses using multiple BC cell lines confirmed that SLFN11 KO rendered cells resistant to cisplatin. The epigenetic modifying drugs 5-azacytidine and entinostat restored SLFN11 expression and resensitized cells to cisplatin and carboplatin in SLFN11-negative BC cell lines. We conclude that SLFN11 is a predictive biomarker for BC patients who undergo platinum-based chemotherapy and that the combination of epigenetic modifiers could rescue refractory BC patients to platinum derivatives by reactivating SLFN11 expression.

Schlafen 11 predicts response to platinum-based chemotherapy in gastric cancers.

BACKGROUND: Although unresectable or recurrent gastric cancers (GC) are frequently treated with platinum-based chemotherapy, response to treatment remains unpredictable. Because Schlafen 11 (SLFN11) is recently identified as a critical determinant of platinum sensitivity, we investigated the potential clinical utility of SLFN11 in the treatment of GC. METHODS: We analysed the correlation between SLFN11 expression and overall survival in 169 GC patients by our established immunohistochemical approach. The impact of SLFN11 expression on the response to platinum and transition of SLFN11 expression upon long-term treatment with platinum were examined using GC cell lines and organoids. RESULTS: GC patients with high-SLFN11 expression exhibited significantly better survival than those with low-SLFN11 expression, and the significance increased when we selected patients treated with platinum-based chemotherapy. Knockout of SLFN11 and reactivation of SLFN11 in GC cells conferred resistance and sensitivity to platinum, respectively. In GC cells and organoids, long-term treatment with oxaliplatin suppressed SLFN11 expression while imparting drug resistance. The acquired resistance to oxaliplatin was reversed by reactivation of SLFN11 with epigenetic modifying drugs. CONCLUSIONS: This is the first report revealing definitive clinical implications of SLFN11 in the treatment of GC patients and providing novel strategies for the drug selection based on SLFN11 expression.

Establishment of oxaliplatin-resistant gastric cancer organoids: importance of myoferlin in the acquisition of oxaliplatin resistance.

BACKGROUND: The attainment of drug resistance in gastric cancer (GC) is a problematic issue. Although many studies have shown that cancer stem cells (CSCs) play an important role in the acquisition of drug resistance, there is no clinically available biomarker for predicting oxaliplatin (L-OHP) resistance in relation to CSCs. Organoid technology, a novel 3D cell culture system, allows harboring of patient-derived cancer cells containing abundant CSCs using niche factors in a dish. METHODS: In this study, we established L-OHP-resistant gastric cancer organoids (GCOs) and evaluated their gene expression profile using microarray analysis. We validated the upregulated genes in the L-OHP-resistant GCOs compared to their parental GCOs to find a gene responsible for L-OHP resistance by qRT-PCR, immunohistochemistry, in vitro, and in vivo experiments. RESULTS: We found myoferlin (MYOF) to be a candidate gene through microarray analysis. The results from cell viability assays and qRT-PCR showed that high expression of MYOF correlated significantly with the IC50 of L-OHP in GCOs. Immunohistochemistry of MYOF in GC tissue samples revealed that high expression of MYOF was significantly associated with poor prognosis, T grade, N grade, and lymphatic invasion, and showed MYOF to be an independent prognostic indicator, especially in the GC patients treated with platinum-based chemotherapy. The knockdown of MYOF repressed L-OHP resistance, cell growth, stem cell features, migration, invasion, and in vivo tumor growth. CONCLUSIONS: Our results suggest that MYOF is highly involved in L-OHP resistance and tumor progression in GC. MYOF could be a promising biomarker and therapeutic target for L-OHP-resistant GC cases.

Uc.63+ contributes to gastric cancer progression through regulation of NF-kB signaling.

BACKGROUND: The transcribed ultraconserved regions (T-UCRs) are a novel class of long non-coding RNAs and are involved in the development of several types of cancer. Although several different papers have described the oncogenic role of Uc.63+, there are no reports mentioning its importance in gastric cancer (GC) biology. METHODS: In this study, we evaluated Uc.63+ expression using clinical samples of GC by qRT-PCR, and also assessed the correlation between Uc.63+ expression and clinico-pathological factors. RESULTS: The upregulation of Uc.63+ was significantly correlated with advanced clinico-pathological features. Knockdown of Uc.63+ significantly repressed GC cell growth and migration, whereas overexpression of Uc.63+ conversely promoted those of GC cells. In situ hybridization of Uc.63+ revealed its preferential expression in poorly differentiated adenocarcinoma. We further conducted a microarray analysis using MKN-1 cells overexpressing Uc.63- and found that NF-κB signaling was significantly upregulated in accordance with Uc.63+ expression. CONCLUSION: Our results suggest that Uc.63+ could be involved in GC progression by regulating GC cell growth and migration via NF-κB signaling.

Use of the Dorsal Vein of the Hand for Arteriovenous Fistula Creation.

A radiocephalic arteriovenous fistula (AVF) in the anatomical snuffbox is the most distal site of AVF in the upper limb. When the cephalic vein distal to the wrist is in poor condition or thrombosed, creating the typical radiocephalic AVF in the distal forearm just proximal to the wrist will likely be considered. However, we have adopted an operative technique for creating a transposed radial artery-dorsal metacarpal vein AVF (RDAVF) in the anatomical snuffbox when possible in such cases. RDAVF is AVF using the most peripheral autologous vein in the upper limb. To our knowledge, the creation of an RDAVF has not been previously reported. We herein describe the steps of the technique and report the successful treatment of a hemodialysis patient who developed occlusion of a radiocephalic AVF in the anatomical snuffbox.

Thyroid function in patients on continuous ambulatory peritoneal dialysis in comparison with chronic kidney disease
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BACKGROUND/METHODS: Thyroid function was evaluated in 14 Japanese patients on continuous ambulatory peritoneal dialysis (CAPD) with end-stage renal disease compared with 11 chronic kidney disease (CKD) stage 1+2 patients (glomerular filtration rate ≥ 60 mL/min/1.73m2). RESULTS: The serum free triiodothyronine (fT3) (2.2 ± 0.3 pg/mL, p < 0.05) levels were lower, and the rate of low triiodothyronine (T3) syndrome was higher (4 of 13 cases, 30.8%) in the CAPD patients than in the CKD stage 1+2 patients (1 of 10 cases, 10.0%, respectively) or the 57 age-matched healthy controls. The serum thyroglobulin (Tg) levels were significantly higher in the CAPD patients (39.7 (13.4 - 178.0) ng/mL) than in the CKD stage 1+2 patients (9.9 (5.5 - 28.8) ng/mL, p < 0.05). High serum Tg levels (> 30 ng/mL) were observed in 66.7% of the CAPD patients. CONCLUSION: The finding from our study suggested the deterioration of thyroid function with higher prevalence of low T3 syndrome in the CAPD patients. Although speculation as to the reasons for this would be unwise at this point, we did note that the serum Tg levels were very high in the CAPD patients.
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Restoration of Autologous Arteriovenous Fistula by Removal of the Occluded Short Venous Part and Venovenous End-To-End Anastomosis in a Hemodialysis Patient.

Standard salvage procedures for occuluded autologous arteriovenous fistula (AVF) in a hemodialysis patient are endovascular and/or surgical therapy. When endovascular therapy and thrombectomy prove unsuccessful, it is most likely that creating a new AVF or arteriovenous graft will be considered. However, if the occuluded venous part is short, we have adopted an operative technique for repair of AVF by removal of the occluded short venous part and venovenous end-to-end anastomosis. To our knowledge, the efficacy and clinical course of restoration of AVF by the technique have not been reported to date. Here, we describe the technique and report the successful treatment of a hemodialysis patient who developed AVF occlusion.

Long-term outcomes of tonsillectomy for IgA nephropathy patients: A retrospective cohort study, two-centre analysis with the inverse probability therapy weighting method.

AIM: The effect of tonsillectomy on IgA nephropathy remains controversial. The aim of this study was to compare the effect of tonsillectomy on the outcome, end stage kidney disease (ESKD) and all-cause death in IgA nephropathy patients who did and did not undergo tonsillectomy. METHODS: All basic data were retrospectively gathered from patients who had undergone renal biopsies at two Japanese clinical centres. Two hundred and twenty-seven patients were eligible for the study, with a median age of 34 (Interquartile range (IQR): 25-43) years and median follow-up of 92 (IQR: 40-178) months. The primary endpoint was the composite outcome of the onset of ESKD and all-cause death before ESKD. We performed a Cox proportional hazard regression analysis after adjusting for patient characteristics using the inverse probability therapy weighting (IPTW) method and a Cox analysis using the Matching method. Similarly, we analyzed these outcomes in a mild cohort. RESULTS: We were unable to find any significant advantages of tonsillectomy in either analysis (IPTW and matching, HR: 0.40 (0.12-1.36) P = 0.072 and 0.78 (0.13-4.64) P = 0.786). However, in the mild cohort analysis, our data showed that the Tonsillectomy group tended to be less likely to reach the composite outcomes than the Not Tonsillectomy group with statistical significance (hazard ratio (HR), <0.001 [CI <0.001 to <0.001, P = 0.039]). CONCLUSION: In this study, our findings led us to conclude that performing tonsillectomy in an early and timely manner may have predisposition of less poor prognosis.

The high prevalence of reversible subclinical hypothyroidism with elevated serum thyroglobulin levels in chronic kidney disease patients
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BACKGROUND: We examined the thyroid function of non-dialysis-dependent chronic kidney disease (CKD) patients in Japan. METHODS: Serum-free thyroxine, free triiodothyronine, thyroid-stimulating hormone (TSH), and thyroglobulin (Tg) levels were evaluated in 37 CKD patients. CKD was defined as sustained kidney damage for more than 3 months and was classified as CKD 1+2 (n = 11), 3+4 (n = 10), or 5 (n = 16), which were defined by glomerular filtration rates of ≥ 60, 15 - 59, or < 15 mL/min/1.73m2, respectively. RESULTS: The prevalence of primary hypothyroidism (TSH ≥ 4.83 mU/L) in CKD 1+2, CKD 3+4, and CKD 5 was 9%, 20%, and 56%, respectively (p < 0.05). Unexpectedly, elevated serum Tg levels (> 30 ng/mL), a marker of the reversible recovery of the thyroid function, were found in 67% of the CKD 5 patients (p < 0.05). The serum TSH and Tg levels became lower, without replacement therapy, after the initiation of hemodialysis and iodine restriction, and there was a significant correlation between the serum TSH and Tg levels in the CKD 5 patients (p < 0.05). CONCLUSION: The high prevalence of reversible hypothyroidism and the TSH-dependent elevation of the serum Tg levels was suggested in Japanese patients with advanced CKD. The excess ingestion and the impaired urinary excretion of iodine may be responsible for this reversible thyroid dysfunction.
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Successful treatment of a patient with refractory nephrotic syndrome with PCSK9 inhibitors: a case report.

BACKGROUND: The proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor evolocumab is a low-density lipoprotein (LDL)-lowering drug with a new mechanism, which is currently available in Japan. Here, for the first time, we report the successful use of the PCSK9 inhibitor in a patient with refractory nephrotic syndrome. CASE PRESENTATION: A 61-year-old woman was diagnosed with minimal change-type nephrotic syndrome in October 2012. She received prednisolone (PSL) and cyclosporin A (CyA), but she experienced several cycles of relapse and remission and was hospitalized in May 2016 due to relapse. However, in spite of steroid pulse therapy and adrenocorticotropic hormone (ACTH) administration, her urinary protein level did not improve. We started her on evolocumab with the expectation of equivalent LDL-lowering effects as seen with LDL apheresis. After that, the LDL cholesterol level and UP/UC were concomitantly decreased, and the serum albumin was increased. This was maintained even when we reduced the PSL dose. This suggests that evolocumab clinically improves the nephrotic condition. CONCLUSION: No other report has described the use of evolocumab for nephrotic syndrome (NS) or its effect on similar nephrotic conditions. We believe that the findings presented here are unique and may be beneficial when treating similar cases.

Transcriptome analysis of an AKT inhibitor-resistant endometrial cancer cell line.

BACKGROUND: Drug resistance in endometrial cancer (EC) is a serious problem and a barrier to improving prognosis. The PI3K/AKT/mTOR pathway is highly activated in EC and can serve as a potential therapeutic target. Inhibitors against AKT have been developed, but resistance to these inhibitors is a concern. This study aimed to establish AKT inhibitor resistant cell lines and identify differentially expressed genes (DEGs) between parental and AKT inhibitor resistant cell lines to understand the mechanism of drug resistance to AKT inhibitors in EC. METHODS: The sensitivity of eight EC cell lines to AKT inhibitor was analyzed. One of them was used to establish a drug-resistant cell line. DEGs were examined using RNA sequencing (RNA-seq). Furthermore, DEGs were comprehensively analyzed to identify hub genes. Hub genes were evaluated using quantitative real-time polymerase chain reaction. RESULTS: RNA-seq identified 617 DEGs. Hub genes were selected using bioinformatics analysis. The top 10 hub genes were TNF, CDH1, CCND1, COL1A1, CDH2, ICAM1, CAV1, THBS1, NCAM1, and CDKN2A. Relative mRNA expression was significantly upregulated for TNF, CDH1, CCND1, THBS1, p16INK4a, and p14ARF and significantly downregulated for CDH2, ICAM1, and NCAM1 in borussertib-resistant EC cell line. CONCLUSIONS: Drug resistance to AKT inhibitors may depend on genes related to cell adhesion-mediated resistance and transforming growth factor ß signaling.

Acquired AKT-inhibitor Resistance Is Mediated by ATP-binding Cassette Transporters in Endometrial Carcinoma.

BACKGROUND/AIM: Endometrial cancer is increasing in prevalence worldwide. It is treated with chemotherapy and radiotherapy, in addition to surgery, but the presence of treatment-resistant tumor cells remains a barrier to effective tumor control. The purpose of this study was to develop drug-resistant cell lines using triciribine, an AKT inhibitor, and investigate the mechanism of acquired resistance. MATERIALS AND METHODS: Triciribine sensitivity assays were performed using Cell Counting Kit-8 (CCK-8) on eight endometrial cancer cell lines. The chosen cell lines were highly sensitive to chemotherapy and radiotherapy. A new triciribine-resistant cell line was established and found to be highly resistant to chemotherapy. Properties of the resistant cell line were identified using molecular and cell biological techniques including CCK-8 and quantitative PCR analysis. RESULTS: HEC-151 had the highest triciribine sensitivity (IC50 value of 0.7±0.1 µM) of the endometrial cancer cell lines tested. We established a triciribine-resistant cell line from HEC-151 by growing cells in the presence of increasing concentrations of triciribine up to 66.6 µM. The resistant HEC-151 cells changed to spindle-shaped morphology and importantly reduced triciribine sensitivity compared to the parental cell line. ABC transporters involved in drug efflux had significantly higher expression levels in ABCB1 (1.4±0.10 times higher), ABCC1 (11.4±0.22 times higher), and ABCC4 (4.5±0.42 times higher). CONCLUSION: In this study, we established a triciribine-resistant cell line from HEC-151 cells. Our data suggest that the mechanism of drug resistance in endometrial cancer cells is attributed to the increased expression of ABC transporters.

Mutually exclusive expression of EZH2 and H3K27me3 in non-small cell lung carcinoma.

Enhancer of zeste homolog 2 (EZH2) epigenetically represses gene expression via trimethylation of lysine 27 on histone 3 (H3K27me3). Non-small cell carcinoma (NSCLC) has been reported to show high EZH2 and low H3K27me3 expression compared to normal lung tissues, but there are no studies examining the expression of EZH2 and H3K27me3 simultaneously with immunohistochemistry. In the present study, the expression of EZH2 and H3K27me3 was examined in surgically resected NSCLC. We enrolled 27 cases of squamous cell carcinoma (SCC), 73 cases of Lepidic, 77 of Papillary/Acinar, 51 of Solid, 31 of Micropapillary, and 12 of Mucinous subtypes of adenocarcinoma. First, we examined the expression of EZH2 and H3K27me3 in normal and metaplastic bronchial epithelium adjacent to NSCLC. Normal bronchial epithelium showed EZH2 expression in a limited number of basal cells and H3K27me3 expression in surface differentiated cells with cilia or mucus. In metaplastic bronchial epithelium, the number of EZH2-positive cells increased in multilayered basal cells, and H3K27me3-positive cells were observed in the superficial layer. Then, EZH2 and H3K27me3 expression was analyzed in NSCLC. Abundant EZH2 and rare H3K27me3 expression was detected in SCC, Papillary/Acinar, Solid and Micropapillary subtypes. In Mucinous subtype, EZH2 expression was hardly detected, and H3K27me3 expression was detected in almost all tumor cells. EZH2-expressing and H3K27me3-expressing tumor cells were similarly observed in Lepidic subtype, but double immunofluorescence revealed that EZH2 and H3K27me3 expression pattern was mutually exclusive. No co-expression of EZH2 and H3K27me3 was detected in all examined subtypes. To our knowledge, there have been no reports describing mutually exclusive expression pattern of EZH2 and H3K27me3.

Utilization of the autologous vein on the ulnar side of the dorsal hand for arteriovenous fistula creation.

We previously described the success and usefulness of two operative techniques for creating a radial artery-first or second dorsal metacarpal vein arteriovenous fistula (AVF) in the first interdigital space of the dorsal hand using the most distal site and autologous veins in the upper limb. These techniques utilize the dorsal metacarpal veins on the radial side of the dorsal hand. Developing these ideas, we devised a novel operative technique for creating a transposed radial artery-third metacarpal vein AVF in the first interdigital space of the dorsal hand using the most distal vein on the ulnar side of the upper limb and most distal site in the upper limb. The distinctive advantage of this technique is that it can be applied to patients whose cephalic vein in the forearm and the dorsal metacarpal veins on the radial side of the dorsal hand are of a poor quality. We herein report the steps of this technique and describe its successful performance in a patient who has been on hemodialysis for 14 months without any additional vascular access interventions or postoperative complications. We consider this technique to be a valuable option in select patients who meet the applicable conditions. The creation of the first AVF as distally as possible is ideal, and it offers a further viable option of distal native vascular access that may be overlooked.