Bobby Alexander

Ureteroscopic and extirpative treatment of upper urinary tract urothelial carcinoma: a 15-year comprehensive review of 160 consecutive patients

Study Type – Therapy (case series)

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.

Nephrotoxin-Induced Renal Cell Injury Involving Biochemical Alterations and Its Prevention With Antioxidant

Background Although nephrotoxic agents or nephrotoxins are known to induce acute renal cell injury, their cytotoxic action is not fully elucidated. It is thus crucial to explore such a cytotoxic mechanism and the increasing volume of reports indicated a significant involvement of oxidative stress. To test this possibility, we investigated if a nephrotoxin would exert oxidative stress, leading to renal cell injury accompanied by certain biochemical alterations. We also examined if specific antioxidant might help prevent such oxidative cell injury. These studies may then help establish a prophylactic or preventive modality for renal cell injury induced by nephrotoxins. Methods As glycerol has been commonly used for studying acute renal failure in animals, whether it would induce cellular injury was tested in renal proximal tubular OK cells in vitro. Cells were exposed to the varying concentrations of glycerol and cell number/viability was determined in 24 hours. Severity of oxidative stress was assessed by lipid peroxidation assay. Possible effects of glycerol on biochemical parameters were also examined on glyoxalase I activity and heat shock protein 90 using spectrophotometric (enzymatic) assay and Western blot analysis. Results Glycerol (2.5%) was highly cytotoxic to OK cells, inducing 95% cell death in 24 hours. Lipid peroxidation assay indicated that nearly 3-fold greater oxidative stress was exerted by this glycerol. Concurrently, glyoxalase I activity was drastically lost by 75% and heat shock protein 90 was partially degraded following glycerol exposure. However, N-acetylcysteine, a potent glutathione-based antioxidant, was capable of almost completely preventing the glycerol-mediated adverse outcomes, such as cell death, glyoxalase I inactivation, and heat shock protein 90 degradation. Conclusions Glycerol is cytotoxic, capable of inducing specific biochemical alterations such as inactivation of glyoxalase I and degradation of heat shock protein 90, which may reflect a breakdown of the cellular detoxification and defense systems, leading ultimately to OK cell death. Nevertheless, as N-acetylcysteine can provide full cytoprotection against such glycerol toxicity, it could be considered a prophylactic modality for nephrotoxin-induced oxidative renal cell injury and death. Keywords Glycerol; Glyoxalase I; Heat shock protein; N-acetylcysteine; Renal cell injury

Additively Enhanced Antiproliferative Effect of Interferon Combined with Proanthocyanidin on Bladder Cancer Cells

Although interferon (IFN) has been often used as immunotherapy for bladder cancer, its efficacy is rather unsatisfactory, demanding further improvement. Combination therapy is one of viable options, and grape seed proanthocyanidin (GSP) could be such an agent to be used with IFN because it has been shown to have anticancer activity. We thus investigated whether combination of IFN and GSP might enhance the overall antiproliferative effect on bladder cancer cells in vitro. Human bladder cancer T24 cells were employed and treated with the varying concentrations of recombinant IFN-α2b (0-100,000 IU/ml), GSP (0-100 μg/ml), or their combinations. IFN-α2b alone led to a ~50% growth reduction at 20,000 (20K) IU/ml, which further declined to ~67% at ≥50K IU/ml. Similarly, GSP alone induced a ~35% and ~100% growth reduction at 25 and ≥50 μg/ml, respectively. When IFN-α2b and GSP were then combined, combination of 50K IU/ml IFN-α2b and 25 μg/ml GSP resulted in a drastic >95% growth reduction. Cell cycle analysis indicated that such an enhanced growth inhibition was accompanied by a G1 cell cycle arrest. This was further confirmed by Western blot analysis revealing that expressions of G1-specific cell cycle regulators (CDK2, CDK4, cyclin E and p27/Kip1) were distinctly modulated with such IFN-α2b/GSP treatment. Therefore, these findings support the notion that combination of IFN-α2b and GSP is capable of additively enhancing antiproliferative effect on T24 cells with a G1 cell cycle arrest, implying an adjuvant therapeutic modality for superficial bladder cancer.

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.

Attenuation of androgenic regulation by brefeldin A in androgen-responsive prostate cancer cells

OBJECTIVES To investigate the effects of an antibiotic brefeldin A (BFA) on androgen-regulated cellular events in androgen-responsive prostate cancer cells, focusing on PSA (prostate-specific antigen) status, cell growth, and bioactivity of androgen receptor (AR). MATERIALS AND METHODS Androgen-responsive human prostate cancer LNCaP cells were employed and 5α-dihydrotestosterone (DHT) was used as an androgenic mediator to induce androgen-modulated cellular events. Effects of BFA on synthesis and secretion of PSA, cell growth, and AR activity were assessed using Tandem PSA assay, trypan blue exclusion method, and AR binding assay, respectively. RESULTS BFA (30 ng/ml) dramatically (90%) blocked secretion of PSA and also reduced cell growth by >75% under non-androgen-regulated condition. Under androgen-stimulated condition using DHT (1 nM), both the cellular and secreted PSA levels as well as cell growth was significantly elevated or stimulated by DHT (compared with controls); however, BFA was capable of completely inhibiting such DHT-stimulated cellular events. In addition, AR binding assay revealed that AR activity has been drastically (~90%) diminished by BFA, likely resulting in interruption of DHT-mediated events. CONCLUSIONS BFA is capable of attenuating androgenic regulation in LNCaP cells such as androgen-stimulated PSA synthesis/secretion and cell growth. This BFA-blocked androgen action appears to be primarily attributed to severe inactivation of AR with BFA because AR is a crucial factor for relaying androgenic messages (to DNA). Therefore, BFA could be considered a promising agent for a more effective treatment of hormone-dependent prostate cancer.

Complications of Robotic-Assisted Laparoscopic Surgery: Iatrogenic and Doulogenic

Robotic surgery has greatly increased in popularity for a wide variety of procedures. Complications encountered in robotic surgeon are often unique; it is a recognition of complications and theire prevention which will allow the benefits of robotic surgery to be optimized. Complications, or adverse events (AEs), in robotic surgery may be viewed as iatrogenic, or due to actions of the physician, and what may be termed “doulogenic” (Gk: doulos, slave), or due to robotic malfunction. ILatrogenic AEs may be unique to robotic surgery, such as injuries due to robotic arm entrapment or movement; doulogenic AEs include arm breakage, stereo viewer failure, bulb explosion, or master tool failure. Complications in robotic surgery are low: most are iatrogenic, from 5–15% in reported series; <1% are doulogenic. The robotic surgeon assumes a primary role in the maintenance of a safe operative environment and the prevention of avoidable iatrogenic or doulogenic complications.

31 RETROPERITONEAL LAPAROSCOPIC ADRENALECTOMY: OUTCOMES IN 26 CONSECUTIVE CASES

INTRODUCTION AND OBJECTIVES: Laparoscopic adrenalectomy (transperitoneal or retroperitoneal) has become the gold standard for the management of functional and nonfunctional adrenal tumors. We present our surgical experience and outcomes of all patients who underwent retroperitoneal laparoscopic adrenalectomy performed over a 90-month period by a single surgeon (MG). METHODS: We retrospectively reviewed 26 consecutive cases of retroperitoneal laparoscopic adrenalectomy between May 2003 and November 2010. All patients had pre-operative imaging and a full endocrinological evaluation prior to surgery. Patients were placed in the flank position and a 3-port retroperitoneal approach was used in all cases. Perioperative data were assessed and outcomes were retrospectively analyzed with long-term follow up. RESULTS: Results are summarized in Table 1. Mean patient age was 52 years. Pre-operative evaluation revealed 19 (73%) functional adrenal tumors. The most common presenting symptom was hypertension (53%). Mean operative time was 121 minutes and mean tumor size was 3.9 cm. Only one case required conversion to open surgery secondary to renal hilum involvement. There was 1 minor complication. Mean postoperative hospital stay was 1.3 days. Final pathological evaluation revealed 5 cases of malignant adrenal tumors (2 adrenal cortical carcinomas, 3 adrenal metastasis). CONCLUSIONS: Retroperitoneal laparoscopic adrenalectomy has become our first line therapy for patients with functional and nonfunctional adrenal tumors given its low complication rate, short hospital stay and excellent surgical outcomes.