Drug-resistant profiles of extracellular vesicles predict therapeutic response in TNBC patients receiving neoadjuvant chemotherapy.

BACKGROUND: Predicting tumor responses to neoadjuvant chemotherapy (NAC) is critical for evaluating prognosis and designing treatment strategies for patients with breast cancer; however, there are no reliable biomarkers that can effectively assess tumor responses. Therefore, we aimed to evaluate the clinical feasibility of using extracellular vesicles (EVs) to predict tumor response after NAC. METHODS: Drug-resistant triple-negative breast cancer (TNBC) cell lines were successfully established, which developed specific morphologies and rapidly growing features. To detect resistance to chemotherapeutic drugs, EVs were isolated from cultured cells and plasma samples collected post-NAC from 36 patients with breast cancer. RESULTS: Among the differentially expressed gene profiles between parental and drug-resistant cell lines, drug efflux transporters such as MDR1, MRP1, and BCRP were highly expressed in resistant cell lines. Drug efflux transporters have been identified not only in cell lines but also in EVs released from parental cells using immunoaffinity-based EV isolation. The expression of drug resistance markers in EVs was relatively high in patients with residual disease compared to those with a pathological complete response. CONCLUSIONS: The optimal combination of drug-resistant EV markers was significantly efficient in predicting resistance to NAC with 81.82% sensitivity and 92.86% specificity.

Exploring miRNA­target gene profiles associated with drug resistance in patients with breast cancer receiving neoadjuvant chemotherapy.

Exosomal microRNAs (miRNAs) are closely related to drug resistance in patients with breast cancer (BC); however, only a few roles of the exosomal miRNA-target gene networks have been clinically implicated in drug resistance in BC. Therefore, the present study aimed to identify the differential expression of exosomal miRNAs associated with drug resistance and their target mRNAs. In vitro microarray analysis was used to verify differentially expressed miRNAs (DEMs) in drug-resistant BC. Next, tumor-derived exosomes (TDEs) were isolated. Furthermore, it was determined whether the candidate drug-resistant miRNAs were also significant in TDEs, and then putative miRNAs in TDEs were validated in plasma samples from 35 patients with BC (20 patients with BC showing no response and 15 patients with BC showing a complete response). It was confirmed that the combination of five exosomal miRNAs, including miR-125b-5p, miR-146a-5p, miR-484, miR-1246-5p and miR-1260b, was effective for predicting therapeutic response to neoadjuvant chemotherapy, with an area under the curve value of 0.95, sensitivity of 75%, and specificity of 95%. Public datasets were analyzed to identify differentially expressed genes (DEGs) related to drug resistance and it was revealed that BAK1, NOVA1, PTGER4, RTKN2, AGO1, CAP1, and ETS1 were the target genes of exosomal miRNAs. Networks between DEMs and DEGs were highly correlated with mitosis, metabolism, drug transport, and immune responses. Consequently, these targets could be used as predictive markers and therapeutic targets for clinical applications to enhance treatment outcomes for patients with BC.

The impact of bladder cuff excision on outcomes after nephroureterectomy for upper tract urothelial carcinoma: An analysis of the ROBUUST 2.0 registry.

OBJECTIVES: We sought to determine whether bladder cuff excision and its technique influence outcomes after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC). METHODS AND MATERIALS: A multicenter, international, retrospective analysis using the ROBotic surgery for Upper tract Urothelial cancer Study (ROBUUST) 2.0 registry identified 1,718 patients undergoing RNU for UTUC between 2015 and 2023 at 17 centers across the United States, Europe, and Asia. Data was gathered on (1) whether bladder cuff excision was performed and (2) what technique was used, including formal excision or other techniques (pluck technique, stripping/intussusception technique) and outcomes. Multivariate and survival analyses were performed to compare the groups. RESULTS: Most patients (90%, 1,540/1,718) underwent formal bladder cuff excision in accordance with EAU and AUA guidelines. Only 4% (68/1,718) underwent resection using other techniques, and 6% (110/1,718) did not have a bladder cuff excised. Median follow up for the cohort was 24 months (IQR 9-44). When comparing formal bladder cuff excision to other excision techniques, there were no differences in oncologic or survival outcomes including bladder recurrence-free survival (BRFS), recurrence-free survival (RFS), metastasis-free survival (MFS), overall survival (OS), or cancer-specific survival (CSS). However, excision of any kind conferred a decreased risk of bladder-specific recurrence compared to no excision. There was no difference in RFS, MFS, OS, or CSS when comparing bladder cuff excision, other techniques, and no excision. CONCLUSIONS: Bladder cuff excision improves recurrence-free survival, particularly when considering bladder recurrence. This benefit is conferred regardless of technique, as long as the intramural ureter and ureteral orifice are excised. However, the benefit of bladder cuff excision on metastasis-free, overall, and cancer-specific survival is unclear.

Decisional and prognostic impact of diagnostic ureteroscopy in high-risk upper tract urothelial carcinoma: A multi-institutional collaborative analysis (ROBUUST collaborative group).

BACKGROUND: Diagnostic ureteroscopy (URS) with or without biopsy remains a subject of contention in the management of upper tract urothelial carcinoma (UTUC), with varying recommendations across different guidelines. The study aims to analyse the decision-making and prognostic role of diagnostic ureteroscopy (URS) in high-risk UTUC patients undergoing curative surgery. MATERIALS AND METHODS: In this retrospective multi-institutional analysis of high-risk UTUC patients from the ROBUUST dataset, a comparison between patients who received or not preoperative URS and biopsy before curative surgery was carried out. Logistic regression analysis evaluated differences between patients receiving URS and its impact on treatment strategy. Survival analysis included 5-year recurrence-free survival (RFS), metastasis-free survival (MFS), cancer-specific survival (CSS) and overall survival (OS). After adjusting for high-risk prognostic group features, Cox proportional hazard model estimated significant predictors of time-to-event outcomes. RESULTS: Overall, 1,912 patients were included, 1,035 with preoperative URS and biopsy and 877 without. Median follow-up: 24 months. Robot-assisted radical nephroureterectomy was the most common procedure (55.1%), in both subgroups. The 5-year OS (P = 0.04) and CSS (P < 0.001) were significantly higher for patients undergoing URS. The 5-year RFS (P = 0.6), and MFS (P = 0.3) were comparable between the 2 groups. Preoperative URS and biopsy were neither a significant predictor of worse oncological outcomes nor of a specific treatment modality. CONCLUSIONS: The advantage in terms of OS and CSS in patients undergoing preoperative URS could derive from a better selection of candidates for curative treatment. The treatment strategy is likely more influenced by tumor features than by URS findings.

Robotic distal ureterectomy for high-risk distal ureteral urothelial carcinoma: a retrospective multicenter comparative analysis (ROBUUST 2.0 collaborative group).

BACKGROUND: The role of kidney-sparing surgery in patients with high-risk upper urinary tract urothelial carcinoma is controversial. The present study aimed to assess oncological and functional outcomes of robot-assisted distal ureterectomy in patients with high-risk distal ureteral tumors. METHODS: The ROBUUST 2.0 multicenter international (2015-2022) dataset was used for this retrospective cohort analysis. High-risk patients with distal ureteral tumors were divided based on type of surgery: robot-assisted distal ureterectomy or robot-assisted nephroureterectomy. A survival analysis was performed for local recurrence-free survival, distant metastasis-free survival, and overall survival. After adjusting for clinical features of the high-risk prognostic group, Cox proportional hazard model was plotted to evaluate significant predictors of time-to-event outcomes. RESULTS: Overall, 477 patients were retrieved, of which 58 received robot-assisted distal ureterectomy and 419 robot-assisted nephroureterectomy, respectively, with a mean (±SD) follow-up of 29.6 months (±2.6). The two groups were comparable in terms of baseline features. At survival analysis, no significant difference was observed in terms of recurrence-free survival (P=0.6), metastasis-free survival (P=0.5) and overall survival (P=0.7) between robot-assisted distal ureterectomy and robot-assisted nephroureterectomy. At Cox regression analysis, type of surgery was never a significant predictor of worse oncological outcomes. At last follow-up patients undergoing robot-assisted distal ureterectomy had significantly better postoperative renal function. CONCLUSIONS: Comparable outcomes in terms of recurrence-free survival, metastasis-free survival, and overall survival between robot-assisted distal ureterectomy and robot-assisted nephroureterectomy patients, and better postoperative renal function preservation in the former group were observed. Kidney-sparing surgery should be considered as a potential option for selected patients with high-risk distal ureteral UTUC.

Analysis of treatment of muscle invasive bladder cancer using the national cancer database: Factors associated with receipt of aggressive therapy.

OBJECTIVES: To characterize the treatments received by muscle-invasive bladder cancer (MIBC) patients, analyze their use according to sociodemographic, clinical, pathologic, and facility variables, and identify possibilities for improvement in care, with the understanding that patients with MIBC face a potentially lethal disease, yet often do not receive guideline-concordant potentially curative therapies. MATERIALS AND METHODS: Using the National Cancer Data Base (NCDB), we analyzed 102,119 patients with MIBC diagnosed from 2009 to 2018. Treatments included cystectomy, radiation, chemotherapy (CT), or observation. Treatments including cystectomy or radiotherapy (RT) ≥50 Gy were considered aggressive therapy (AT). A multivariable generalized estimating equation model was used to assess the impact of the independent variables with receiving AT, using SAS version 9.4. RESULTS: The median age was 73 years, with 72.9% male, 84.3% White, and 7.1% Black. Stage distribution was 59.4% stage II, 23.0% stage III, and 17.6% stage IV. Overall, 55.2% of patients received AT, while 41.1% did not, with 26.6% receiving observation alone after transurethral resection of bladder tumor. 45.4% received cystectomy, 9.8% received RT, and 12.8% received CT as primary treatment. Notably, over 30% of patients ages 50 to 70 did not receive aggressive therapy. On multivariate analysis, factors associated with nonreceipt of AT included age >70 (OR < 0.79, P < 0.0001), Black race (OR 0.70, P < 0.0001), underinsured status (OR 0.62, P < 0.0001), high comorbidity (OR 0.74, P < 0.0001), and treatment at low volume (OR 0.72 P < 0.0001) or nonacademic cancer program (OR 0.54, P < 0.0001). Long-term trends included increases in utilization of perioperative CT (17.5% in 2009 to 46.7% in 2018, P < 0.001), and chemoradiation (5.4% in 2009 to 8.8% in 2018, P < 0.001). Using Cox regression analysis to control for confounding variables, receipt of aggressive therapy was associated with improved overall survival. CONCLUSIONS: Over a third of patients did not receive AT for MIBC, with many of these patients seemingly eligible by age and comorbidity status. Prospective studies are needed to determine why these patients do not receive AT. A better understanding of patient vs. access to care vs. provider factors will help to focus efforts to improve care for MIBC patients.

Micronucleus formation in human keratinocytes is dependent on radiation quality and tissue architecture.

The cytokinesis-block micronucleus (MN) assay was used to assess the genotoxicity of low doses of different types of space radiation. Normal human primary keratinocytes and immortalized keratinocytes grown in 2D monolayers each were exposed to graded doses of 0.3 or 1.0 GeV/n silicon ions or similar energies of iron ions. The frequencies of induced MN were determined and compared to γ-ray data. RBE(max) values ranged from 1.6 to 3.9 for primary keratinocytes and from 2.4 to 6.3 for immortalized keratinocytes. At low radiation doses ≤ 0.4 Gy, 0.3 GeV/n iron ions were the most effective at inducing MN in normal keratinocytes. An "over-kill effect" was observed for 0.3 GeV/n iron ions at higher doses, wherein 1.0 GeV/n iron ions were most efficient in inducing MN. In immortalized keratinocytes, 0.3 GeV/n iron ions produced MN with greater frequency than 1.0 GeV/n iron ions, except at the highest dose tested. MN formation was higher in immortalized keratinocytes than in normal keratinocytes for all doses and radiation qualities investigated. MN induction was also assessed in human keratinocytes cultured in 3D to simulate the complex architecture of human skin. RBE values for MN formation in 3D were reduced for normal keratinocytes exposed to iron ions, but were elevated for immortalized keratinocytes. Overall, MN induction was significantly lower in keratinocytes cultured in 3D than in 2D. Together, the results suggest that tissue architecture and immortalization status modulate the genotoxic response to space radiation, perhaps via alterations in DNA repair fidelity.