Prostate Cancer: Under-representation of African American Men in Research Studies Used in the Latest NCCN Guidelines.

OBJECTIVE: To evaluate racial data in studies used in current NCCN prostate cancer guidelines. These guidelines represent the latest information that informs clinical practice. Prostate cancer disproportionately affects mortality in Black patients compared to White patients at a 2.1-fold higher death rate. However, this racial disparity is not accounted for when including patients in research. METHODS: The studies referenced in the latest NCCN guidelines were evaluated for inclusion of racial demographics, and whether they properly account for the higher mortality rate of prostate cancer seen in Black patients. We then analyzed topics within prostate cancer. RESULTS: After application of exclusion criteria, 547 of 878 studies were included for analysis; of those, only 32.4% included demographic data. Overall, Black patients accounted for 472,476 (12.8%) of total patients, while 3,023,007 (81.7%) patients were White. These findings were consistent with specific areas including risk stratification (12% vs 75%), imaging and staging (11% vs 80%), treatment (16% vs 81%), recurrence (15% vs 73%), castration-sensitive prostate cancer (9% vs 84%), castration-resistant prostate cancer (8% vs 73%), and metastatic bone disease (7% vs 84%). CONCLUSION: Our analysis showed consistently that although the guidelines utilize the best research, such studies often do not report racial demographics or have patient populations that do not reflect racial differences in mortality of prostate cancer. Our study questions the generalization of these studies to Black patients. Future research should emphasize inclusion of racial demographics and recruit appropriately representative study cohorts.

Case series - Prioritizing bladder-sparing treatments in patients with urinary tract leiomyoma: A report of three cases and updated literature review.

Urinary tract leiomyomas are rare, benign mesenchymal tumors that are traditionally treated with complete surgical excision. We present three cases of urinary tract leiomyoma - two located in the bladder and one in the ureter. Both bladder leiomyomas were treated with transurethral resection of bladder tumor (TURBT) with no evidence of recurrent disease, while the upper tract leiomyoma was managed with surveillance by patient preference, which to our knowledge, has not been previously described. The ureteral leiomyoma has remained stable at five years followup from initial diagnosis. Given the benign nature of leiomyomas and the overall low recurrence rate reported in the literature, bladder-sparing options should be emphasized when feasible, with active surveillance potentially applicable for highly select patients.

Finding the Next Resident Physicians in the COVID-19 Global Pandemic: An Applicant Survey on the 2020 Virtual Urology Residency Match.

OBJECTIVE: To assess interviewing applicant perceptions of a virtual urology residency interview in the setting of changes mandated by COVID-19 and to determine applicant preference for virtual or in person interviews. Applicant perceptions of multiple interview components were queried to identify program specific and interview modality specific strengths or weaknesses in the 2020 to 2021 Urology Match. METHODS: A 12 question multiple choice and free text survey was emailed to 66 virtually interviewed applicants for open residency positions at a metropolitan training program after conclusion of interviews. Items of interest included interview type preference, overall interview impression, and recommendations for improvement. RESULTS: A total of 50 of 66 (76%) applicants completed the survey corresponding to approximately 11% of the 2020 national urology applicant pool. A total of 49 of 50 (96%) respondents assessed faculty interaction and the virtual platform positively. A total of 38 of 50 (76%) was satisfied with their resident interaction and 32 of 50 (64%) applicants stated they were able to satisfactorily evaluate the site and program. Ultimately, 39 of 50 (78%) respondents would have preferred an in person interview to our virtual interview. Respondents cited challenges in assessing program culture and program physical site virtually. CONCLUSION: The majority of survey respondents indicated a preference for in person interviews. A smaller proportion of applicants preferred virtual interviews citing their convenience and lower cost. Efforts to improve the virtual interview experience may focus on improving applicant-resident interaction and remote site assessment.

The Two-Point Technique for Fluoroscopic-Guided Endoscopic Procedures in Urology: A Validation Study.

Introduction: The widespread use of diagnostic and therapeutic ionizing radiation raises concerns regarding excessive occupational and patient exposure. In this study, we test a novel fluoroscopic technique that has the potential to minimize radiation dose during urologic procedures. Materials and Methods: A prospective evaluation of all patients undergoing endoscopic urologic procedures in our institution was conducted. A "two-point technique (TPT)" is described in which the fluoroscope image intensifier (c-arm) is shifted between caudal and cephalad set points of the operative field. We wished to determine whether patient radiation exposure was lower with TPT than with a non-structured conventional technique, referred to as the cognitive fluoroscopic technique (CFT), in which the manipulation of the c-arm was at the discretion of the user. We obtained all clinical, radiographic, and fluoroscopic data of patients in the study period and used unpaired nonparametric statistical analysis of univariates entered stepwise into a logistic regression model. Results: A total of 106 endoscopic urologic procedures from January 2016 to November 2018 were reviewed. Forty-four (41.5%) cases were performed using TPT and 62 (58.5%) using CFT. The mean fluoroscopy time of TPT vs CFT was 71.1 (±60.8) seconds vs 104.5 (±91.6) seconds, respectively (p = 0.04), and the mean radiation dose on TPT vs CFT was 11.6 (±10.6) mGy vs 20.3 (±24.3) mGy, respectively (p = 0.03). TPT was an independent predictor of reduced operative room (OR) time and fluoro time (p < 0.05), while body mass index, age, and operator were not. Conclusion: The "TPT" helps reducing radiation dose and fluoroscopic time during endoscopic urologic procedures. The TPT is useful to lower radiation exposure to patients and OR staff.

Contemporary Trends in Percutaneous Nephrolithomy Across New York State: A Review of the Statewide Planning and Research Cooperative System.

Introduction and Objectives: Percutaneous nephrolithotomy (PCNL) is a complex multistep surgery that has shown a steady increase in use for the past decade in the United States. We sought to evaluate the trends and factors associated with PCNL usage across New York State (NYS). Our goal was to characterize patient demographics and socioeconomic factors across high-, medium-, and low-volume institutions. Materials and Methods: We searched the NYS, Statewide Planning and Research Cooperative System (SPARCS) database from 2006 to 2014 using ICD-9 Procedure Codes 55.04 (percutaneous nephrostomy with fragmentation) for all hospital discharges. Patient demographics including age, gender, race, insurance status, and length of hospital stay were obtained. We characterized each hospital as a low-, medium-, or high-volume center by year. Patient and hospital demographics were compared and reported using chi-square analysis and Student's t-test for categorical and continuous variables, respectively, with statistical significance as a p-value of <0.05. Results: We identified a total of 4576 procedures performed from 2006 to 2014 at a total of 77 hospitals in NYS (Table 1). Total PCNL volume performed across all NYS hospitals increased in the past decade, with the greatest number of procedures performed in 2012 to 2013. Low-volume institutions were more likely to provide care to minority populations (21.4% vs 17.3%, p < 0.001) and those with Medicaid (25.5% vs 21.5%, p < 0.001). High-volume institutions provided care to patients with private insurance (42.1% vs 34.0%, p < 0.001) and had a shorter length of stay (3.3 days vs 4.1 days, p < 0.001). Conclusion: Our data provide insight into the patient demographics of those treated at high-, medium-, and low-volume hospitals for PCNL across NYS. Significant differences in race, insurance status, and length of stay were noted between low- and high-volume institutions, indicating that racial and socioeconomic factors play a role in access to care at high-volume centers.

Device Malfunctions and Complications Associated with Benign Prostatic Hyperplasia Surgery: Review of the Manufacturer and User Facility Device Experience Database.

Introduction and Objectives: Multiple surgical therapies for benign prostatic hyperplasia (BPH) have been developed to decrease complications and increase provider efficiency. We investigated contemporary BPH treatment device-related adverse events by searching a publicly available database. Materials and Methods: The Manufacturer and User Facility Device Experience (MAUDE) database was queried for contemporary BPH treatments. All devices were evaluated for malfunction, patient complications, and manufacturer review. The MAUDE adverse event classification system was used to standardize complications. Univariate analysis was performed to identify associations between BPH devices and adverse events. Results: A total of 2567 reports were identified: transurethral resection of the prostate (TURP) 197 (7.67%), holmium laser enucleation of the prostate (HoLEP) 39 (1.52%), GreenLight™ 2315 (90.2%), and UroLift® 16 (0.62%). The most common deviations for each modality included cutting loop detachment during TURP 116 (58.9%), morcellator dysfunction for HoLEP 23 (58.9%), tip fracture/detachment for GreenLight (68.8%), and failure to deploy during UroLift 10 (62.5%). Only 18 (0.7%) patients required medical/surgical management (MAUDE II-IV) due to a device complication. No significant relationship was seen between each modality and complications; however, morcellator use (27.8%) was observed in higher grade complications. Manufacturer review occurred in 61.7% of cases, with 41.3% of reviewed cases finding the operator the cause of the malfunction. Conclusion: Each BPH modality investigated had minimal patient harm with over 99% of patients experiencing no complication after device malfunction. Of note, great care should be taken with morcellator use during HoLEP as it had the greatest number of MAUDE II to IV complications among all devices. Manufacturer review revealed that over 40% of cases were due to misuse by the user. Therefore, urologists should select the modalities they are most familiar with to decrease patient harm and prevent device malfunctions.

Prophylactic effect of ethyl pyruvate on renal ischemia/reperfusion injury mediated through oxidative stress.

PURPOSE: As oxidative stress (OXS) has been shown to play a primary role in renal ischemia/reperfusion injury (RIRI), we investigated whether antioxidant such as ethyl pyruvate (EPy) might effectively prevent RIRI. Possible prophylactic effects of EPy and mannitol (Mann), one of perioperative agents often used, were tested against harmful OXS in vitro. METHODS: Hydrogen peroxide (H2O2) was used to exert OXS on the renal proximal tubular MDCK cells. Severity of OXS and protective effects of EPy and Mann were assessed by lipid peroxidation assay and cell viability test, respectively. The cytotoxic mechanism of H2O2 was explored by examining the status of glycolysis, metabolic signaling pathways, cell cycle, and induction of apoptosis. RESULTS: Although H2O2 (500 µM) increased OXS by ~ 3.5 times of controls, EPy (1 mM) fully reduced it to the basal level. Cell viability declined to merely 10% by H2O2 was regained to > 90% with EPy. Hexokinase activity and ATP level also declined significantly by H2O2, but they sustained 80-90% with EPy. Additionally, H2O2 led to the modulations of metabolic signaling regulators, a G1 cell cycle arrest, and induction of apoptosis, which were yet prevented with EPy. Unlike EPy, Mann had virtually little effects. CONCLUSIONS: OXS can indeed lead to the significant cell viability reduction through its adverse cellular effects, ultimately resulting in RIRI. However, EPy appears to prevent these effects and protect MDCK cells, while Mann does not. Thus, EPy could be a more effective prophylactic renoprotective agent (than Mann) against oxidative renal cell injury including RIRI.

Penile and Scrotal Strangulation due to Metal Rings: Case Reports and a Review of the Literature.

Penile and scrotal entrapment from a metal ring placed at the base of the penis is a rare, but important clinical dilemma encountered in urology. Emergent presentation to the urologist, after ring placement far longer than safely practiced, risks ischemic and permanent injury to penile, scrotal, and intrascrotal structures. Treating urologists should be aware of the prevalence of metal ring use, their potential complications, and the surgical approach to their safe removal. We present two patients who were identified at our institution with strangulating injuries of retained penile rings. The first patient was a healthy, 43-year-old male with a metal ring retained for 24 hours that was safely removed with industrial bolt cutters. The second patient, a 74-year-old male, died as a result of sepsis from injuries secondary to penoscrotal ischemia after >48 hour ring retention despite prompt removal at emergent presentation. Although rare, sexual practices may include the use of penoscrotal rings. When retained, ischemic injury and edema may lead to strangulation. Emergent removal may require industrial equipment that is not within the confines of normal operating room tools. Tissue injury may be severe and sepsis life-threatening, even after ring removal.

Device-Related Adverse Events During Percutaneous Nephrolithotomy: Review of the Manufacturer and User Facility Device Experience Database.

INTRODUCTION AND OBJECTIVES: Percutaneous nephrolithotomy (PCNL) is an established technique for removal of large stones from the upper urinary tract. It is a complex multistep procedure requiring several classes of instruments that are subject to operator misuse and device malfunction. We report device-related adverse events during PCNL from the Manufacturer and User Facility Device Experience (MAUDE) database using a recently developed standardized classification system. MATERIALS AND METHODS: The MAUDE database was queried for "percutaneous nephrolithotomy" from 2006 to 2016. The circumstances and patient complications associated with classes of devices used during PCNL were identified. We then utilized a novel MAUDE classification system to categorize clinical events. Logistic regression analysis was performed to identify associations between device classes and severe adverse events. RESULTS: A total of 218 device-related events were reported. The most common classes included: lithotripter 53 (24.3%), wires 43 (19.7%), balloon dilators 30 (13.8%), and occlusion balloons 28 (12.8%). Reported patient complications included need for a second procedure 12 (28.6%), bleeding 8 (19.0%), retained fragments 7 (16.7%), prolonged procedure 4 (9.5%), ureteral injury 2 (4.8%), and conversion to an open procedure 3 (7.1%). Using a MAUDE classification system, 176 complications (81%) were Level I (mild/none), 26 (12%) were Level II (moderate), 15 (7%) were Level III (severe), and 1 (0.5%) was Level IV (life threatening). On univariate analysis, balloon dilators had the highest risk of Level II-IV complications compared with the other device classes [odds ratio: 4.33, confidence interval: 1.978, 9.493, p < 0.001]. The device was evaluated by the manufacturer in 93 (42.7%) cases, with 54.8% of reviewed cases listing the source of malfunction as misuse by the operator. CONCLUSIONS: PCNL is subject to a wide range of device-related adverse events. A MAUDE classification system is useful for standardized, clinically-relevant reporting of events. Our findings highlight the importance of proper surgeon training with devices to maximize efficiency and decrease harm.

Antioxidant and Renoprotective Effects of Mushroom Extract: Implication in Prevention of Nephrolithiasis.

BACKGROUND: The pathogenesis of nephrolithiasis (kidney stone) remains elusive, while several therapeutic options are available but not effective as we expected. Accumulating data yet suggest that oxidative stress (generation of oxygen free radicals) may play a primary role in its occurrence. Particularly, calcium oxalate (CaOx) is a key element in the most common form (> 75%) of kidney stones, and its crystal form known as CaOx monohydrate (COM) has been shown to exert oxidative stress, facilitating CaOx stone formation. Hence, diminishing oxidative stress with certain antioxidants could be a potential strategic approach. We are interested in a bioactive extract of Poria mushroom, PE, which has been shown to have antioxidant and renoprotective activities. Accordingly, we investigated if PE might have antioxidant activity that would have implication in prevention of kidney stone formation. METHODS: Renal epithelial LLC-PK1 cells were employed and exposed to COM or hydrogen peroxide (H2O2) as a positive control capable of exerting oxidative stress. Possible antioxidant and protective effects of PE against oxidative stress (exerted by COM or H2O2) were assessed by cell viability test and lipid peroxidation (LPO) assay. To explore its protective mechanism, two glycolytic parameters, hexokinase (HK) activity and ATP synthesis, were examined and cell cycle analysis was also performed. RESULTS: Both H2O2 and COM led to a significant (P < 0.05) reduction in cell viability, accompanied by severe oxidative stress assessed by LPO assay. Such oxidative stress also caused the significant decline in HK activity and cellular ATP level, indicating the inhibition of glycolysis. Cell cycle analysis further indicated that oxidative stress interfered with cell cycle, inducing a G1 cell cycle arrest that presumably results in the cessation of cell proliferation. However, PE was capable of significantly preventing or diminishing all these cellular effects mediated through oxidative stress (exerted by H2O2 and COM). CONCLUSIONS: The present study shows that the mushroom extract PE appears to have antioxidant and renoprotective effects against oxidative stress exerted by COM in renal cells. Therefore, PE with antioxidant activity is considered a promising natural agent that may have clinical implications in prevention of nephrolithiasis primarily induced by oxidative stress.

Potent Anticancer Effects of Bioactive Mushroom Extracts (Phellinus linteus) on a Variety of Human Cancer Cells.

BACKGROUND: Although several therapeutic options are currently available for patients with various cancers, the outcomes are often disappointing and a more effective modality needs to be promptly established. We have been exploring an alternative approach using natural agents and two bioactive mushroom extracts isolated from Phellinus linteus (PL), namely PL-ES and PL-I-ES, were of our interest. As anticancer effects of similar extracts have been reported in several cancers, we investigated whether PL-ES and PL-I-ES might have such anticancer activities on a variety of human cancer cells in vitro. METHODS: Ten different types of human cancer cell lines, including three metastatic prostate, bladder, kidney, lung, breast, stomach, liver, and brain cancer cells, were employed and tested with PL-ES or PL-I-ES. Cell growth/viability, exertion of oxidative stress, and induction of apoptosis were assessed by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay, lipid peroxidation (LPO) assay, and specific enzymatic assay, respectively. RESULTS: PL-ES (100 µg/mL) exhibited potent anticancer activity, resulting in a significant (40-80%) growth reduction in all 10 cancer cells at 72 hours. PL-I-ES (100 µg/mL) was effective on only four cancer cells but its higher concentration at 250 µg/mL led to a significant (25-90%) growth reduction in seven cancer cells. LPO assays indicated that such a significant growth reduction by PL-ES (100 µg/mL) or PL-I-ES (100 or 250 µg/mL) could result from cell death due to a cytotoxic effect of oxidative stress (through free radicals). Moreover, enzymatic assays for caspase-3 (Csp-3) and caspase-9 (Csp-9), the pro-apoptotic regulators, showed that both enzymes were significantly activated by PL-ES or PL-I-ES, indicating that cell death due to oxidative stress was more likely associated with apoptosis. CONCLUSIONS: The present study shows that both PL-ES and PL-I-ES indeed have anticancer effects on a variety of cancer cells, although PL-ES appears to be more potent than PL-I-ES. Such an anticancer effect is presumably attributed to oxidative stress, which will ultimately lead to apoptosis. Therefore, these two bioactive mushroom extracts may have clinical implications in a more effective therapeutic option for a variety of human malignancies.

Alternative therapeutic approach to renal-cell carcinoma: induction of apoptosis with combination of vitamin K3 and D-fraction.

PURPOSE: Because of a dismal prognosis for advanced renal-cell carcinoma (RCC), an alternative therapeutic approach, using vitamin K3 (VK3) and D-fraction (DF) was investigated. VK3 is a synthetic VK derivative and DF is a bioactive mushroom extract, and they have been shown to have antitumor activity. We examined if the combination of VK3 and DF would exhibit the improved anticancer effect on RCC in vitro. MATERIALS AND METHODS: Human RCC, ACHN cell line, were treated with varying concentrations of VK3, DF, or a combination of the two. Cell viability was assessed at 72 hours by MTT assay. To explore the possible anticancer mechanism, studies on cell cycle, chromatin modifications, and apoptosis were conducted. RESULTS: VK3 alone led to a ~20% reduction in cell viability at 4 µM, while DF alone induced a 20% to 45% viability reduction at ≥ 500 µg/mL. A combination of VK3 (4 µM) and DF (300 µg/mL) led to a drastic >90% viability reduction, however. Cell cycle analysis indicated that VK3/DF treatment induced a G1 cell cycle arrest, accompanied by the up-regulation of p21(WAF1) and p27(Kip1). Histone deacetylase (HDAC) was also significantly (~60%) inactivated, indicating chromatin modifications. In addition, Western blot analysis revealed that the up-regulation of Bax and activation of poly-(ADP-ribose)-polymerase (PARP) were seen in VK3/DF-treated cells, indicating induction of apoptosis. CONCLUSIONS: The combination of VK3 and DF can lead to a profound reduction in ACHN cell viability, through a p21(WAF1)-mediated G1 cell cycle arrest, and ultimately induces apoptosis. Therefore, the combination of VK3/DF may have clinical implications as an alternative, improved therapeutic modality for advanced RCC.

Preventive effect of specific antioxidant on oxidative renal cell injury associated with renal crystal formation.

OBJECTIVE: To investigate whether calcium oxalate monohydrate (COM), a key element of hyperoxaluria, would induce renal cell injury through oxidative stress and also whether certain antioxidants could prevent chemically induced renal crystal formation in rats. MATERIALS AND METHODS: COM-exerted oxidative stress on the kidney epithelial Madin-Darby canine kidney cells was assessed using the lipid peroxidation assay. Glyoxalase I (Gly-I) activity was also determined. Two antioxidants, vitamin C and N-acetylcysteine (NAC), were then tested to determine whether they could abolish such oxidative stress in Madin-Darby canine kidney cells. Both antioxidants were also tested to determine whether they might prevent or reduce renal crystal formation induced with ethylene glycol (EG) and vitamin D3 (VD3) in Wistar rats. RESULTS: COM (200 µg/mL) demonstrated ∼1.3-fold greater oxidative stress with a significant reduction in cell viability and Gly-I activity compared with controls. However, such adverse events were almost completely prevented with NAC but not with vitamin C. In the animal study, no renal crystals were seen in the sham group. However, numerous crystals, with reduced Gly-I activity and elevated oxidative stress, were found in the EG-VD3 group. However, markedly (>70%) fewer crystals, with full Gly-I activity and diminished oxidative stress, were detected in the EG-VD3+NAC group. CONCLUSION: COM exerted oxidative stress on Madin-Darby canine kidney cells, leading to cell viability reduction and Gly-I inactivation, with NAC fully preventing such adverse consequences. Similarly, numerous crystals with Gly-I inactivation and elevated oxidative stress seen in the rats (EG-VD3) were also significantly prevented with NAC supplement. Thus, NAC might have clinical implications in preventing oxidative renal cell injury and, ultimately, kidney stone formation.

Possible hypoglycemic action of SX-fraction targeting insulin signal transduction pathway.

BACKGROUND: SX-fraction (SXF) is a bioactive glycoprotein with hypoglycemic activity that has been demonstrated in our pilot clinical study. However, how it would actually work in diabetic patients remains unclear. To explore such a mechanism, the effects of SXF on the insulin signal transduction pathway were investigated using skeletal muscle L6 cells in vitro. METHODS: L6 cells were first differentiated to myotubes expressing several biochemical parameters that were examined in this study. Myotubes were exposed to a high concentration (35 mM) of glucose (Glc) alone or in combination with SXF or insulin for 24 hours. Possible effects of these agents on activities of insulin receptor (IR), IR substrate 1 (IRS-1), and Akt, which are key elements involved in the signal pathway, were assessed using enzyme-linked immunosorbent assay (ELISA). Any changes in Glc uptake were also determined. RESULTS: High Glc indeed led to inactivation of IR, IRS-1, and subsequent Akt in myotubes, indicating an interruption of the signal pathway. However, such inactivation was reversed or reactivated by SXF, presumably aiding the occurrence of successive signaling events. Measurement of Glc uptake to assess the outcome of this signaling cascade showed that high Glc decreased Glc uptake (interfering with the signal pathway), but SXF was capable of overcoming such a suppressive effect, resulting in the increased Glc uptake. Insulin was used as a positive control in this study and all results were nearly compatible to those obtained from SXF. CONCLUSION: The present study suggests that SXF may specifically target the insulin signal pathway, and, in particular, the IR and IRS-1 therein that trigger the subsequent signaling events. As a result, SXF could activate such an impaired signal pathway through high Glc or under a hyperglycemic milieu, thereby ultimately facilitating Glc uptake. This may then account for possible hypoglycemic action of SXF.

Induction of cell death in renal cell carcinoma with combination of D-fraction and vitamin C.

HYPOTHESIS: Although several conventional therapeutic options for advanced renal cell carcinoma (RCC) are currently available, the unsatisfactory outcomes demand establishing more effective interventions. D-fraction (PDF), a bioactive proteoglucan of Maitake mushroom, demonstrates anticancer and immunomodulatory activities, which are also shown to be potentiated by vitamin C (VC). We thus hypothesized that a combination of PDF and VC (PDF + VC) could be an alternative approach to more effectively inhibit the growth of RCC. STUDY DESIGN: We examined the dose-dependent effects of PDF + VC on RCC cell viability and also performed biochemical assays to explore the growth regulatory mechanism. METHODS: Human RCC, ACHN cell line, was employed and exposed to varying concentrations of PDF or VC and their combinations. Cell viability at specified times was determined by MTT assay. Lipid peroxidation assay, cell cycle analysis, and Western blot analysis were also performed. RESULTS: PDF or VC alone led to the significant reduction in cell viability at 72 hours with PDF >500 µg/mL and VC ≥300 µM. When various combinations of PDF and VC were tested, the combination of the ineffective concentrations of PDF (300 µg/mL) and VC (200 µM) resulted in ~90% cell death in 24 hours. Lipid peroxidation assay then indicated significantly (~2.5 fold) elevated oxidative stress with this PDF + VC. Cell cycle analysis also indicated a G1 cell cycle arrest following a 6-hour PDF + VC treatment. Western blots further revealed a downregulation of Bcl2, an upregulation of Bax, and proteolytic activation of PARP (poly[ADP-ribose] polymerase) in PDF + VC-treated cells, indicating induction of apoptosis. CONCLUSION: The present study demonstrates that the combination of PDF and VC can become highly cytotoxic, inducing severe cell death in ACHN cells. This cytotoxic mechanism appears to be primarily attributed to oxidative stress, accompanied by a G1 cell cycle arrest. Such cell death induced by PDF + VC could be more likely linked to apoptosis, as indicated by the modulation of apoptosis regulators (Bcl2, Bax, and PARP). Therefore, as PDF and VC may work synergistically to induce apoptotic cell death, they may have clinical implications in an alternative, improved therapeutic modality for advanced RCC.