Totally retroperitoneal approach for robot-assisted nephroureterectomy with bladder cuff without repositioning.

INTRODUCTION: Robot-assisted nephroureterectomy (RANU) for upper urinary tract urothelial carcinoma is typically performed via the transperitoneal approach because of limited surgical space. However, a retroperitoneal approach may be preferable in patients with a history of abdominal surgery or in those in whom pelvic lymph node dissection is unnecessary. MATERIALS AND SURGICAL TECHNIQUES: RANU via the retroperitoneal approach was selected for two patients diagnosed with high-grade upper urothelial carcinoma with a history of abdominal surgery. Nephrectomy was performed in the 90° flank position, and the bed was tilted at 20°. The retroperitoneal space was extended, and the robot trocar was subsequently repositioned in the left lower quadrant. After redocking the robot, the distal ureter was dissected, and the bladder cuff was resected en bloc along with the kidney and the ureter. Neither patient had any complications within 3 months postoperatively. DISCUSSION: By devising a new technique for trocar placement, total retroperitoneal RANU without repositioning was possible, even in a small patient.

Real-world sequential treatment patterns and clinical outcomes among patients with advanced urothelial carcinoma in Japan.

OBJECTIVES: Immune checkpoint inhibitors and enfortumab vedotin have opened new avenues for sequential treatment strategies for locally advanced/metastatic urothelial carcinoma (la/mUC). In the pre-enfortumab vedotin era, many patients could not receive third-line treatment owing to rapid disease progression and poor general status. This study aimed to analyze real-world sequential treatment practices for la/mUC in Japan, with a focus on patients who do not receive third-line treatment. METHODS: We analyzed data for 1023 la/mUC patients diagnosed between January 2020 and December 2021 at 54 institutions from a Japanese nationwide cohort. RESULTS: At the median follow-up of 28.5 months, the median overall survival from first-line initiation for 905 patients who received systemic anticancer treatment was 19.1 months. Among them, 81% and 32% received second- and third-line treatment. Notably, 52% had their treatment terminated before the opportunity for third-line treatment. Multivariate logistic regression analysis revealed that low performance status (≥1), elevated neutrophil-to-lymphocyte ratio (≥3), and low body mass index (<21 kg/m2) at the start of first-line treatment were independent risk factors for not proceeding to third-line treatment (p = 0.0024, 0.0069, and 0.0058, respectively). In this cohort, 33% had one of these factors, 36% had two, and 15% had all three. CONCLUSIONS: This study highlights the high frequency of factors associated with poor tolerance to anticancer treatment in la/mUC patients. The findings suggest the need to establish optimal sequential treatment strategies, maximizing efficacy within time and tolerance constraints, while concurrently providing strong supportive care, considering immunological and nutritional aspects.

[Evaluation of Patients with Localized Prostate Cancer in whom Long-Term Successful Androgen Deprivation Therapy was Ceased].

We evaluated the clinical course of patients with localized prostate cancer in whom long-term successful androgen deprivation therapy (ADT) was ceased. Study subjects were 24 patients with stage B prostate cancer who were initially treated with ADT for a median duration of 93 months. The median age at the cessation of ADT was 84 years. The median nadir serum prostate specific antigen (PSA) level was 0.022 ng/ml. The median duration of follow-up from the cessation of ADT was 31 months. During follow-up, five patients showed PSA elevation of ≥2 ng/ml from the nadir. Serum testosterone level was tested in 20 patients, and five showed testosterone recovery ≥0.5 ng/ml. Seven patients died from diseases other than prostate cancer, but there were no deaths caused by prostate cancer. This study demonstrated that long-term successful ADT for localized prostate cancer could be ceased with adequate follow-up evaluation.

Generating a new mouse model for nuclear PTEN deficiency by a single K13R mutation.

Many human diseases, including cancer and neurological abnormalities, are linked to deficiencies of phosphatase and tensin homolog deleted on chromosome ten (PTEN), a dual phosphatase that dephosphorylates both lipids and proteins. PTEN functions in multiple intracellular locations, including the plasma membrane and nucleus. Therefore, a critical challenge to understand the pathogenesis of PTEN-associated diseases is to determine the specific role of PTEN at different locations. Toward this goal, the current study generated a mouse line in which lysine 13, which is critical for the nuclear localization of PTEN, is changed to arginine in the lipid-binding domain using the CRISPR-Ca9 gene-editing system. We found that PTENK13R mice show a strong decrease in the localization of PTEN in the nucleus without affecting the protein stability, phosphatase activity, and phosphorylation in the C-terminal tail region. PTENK13R mice are viable but produce smaller neurons and develop microcephaly. These data demonstrate that PTENK13R mice provide a useful animal model to study the role of PTEN in the nucleus in vivo.

Nuclear PTEN deficiency and heterozygous PTEN loss have distinct impacts on brain and lymph node size.

Defects in PTEN, a critical tumor suppressor, are associated with tumorigenesis and aberrant organ sizes. It has been shown that heterozygous PTEN loss increases brains and neuron size, while the specific loss of nuclear PTEN has the opposite effect. Here, we investigate the impact of a combination of heterozygous PTEN loss and nuclear PTEN loss on the size of various organs, including the brain, liver, thymus, spleen, and inguinal lymph node. We found that the effect of the combination varies among organs. Notably, the combination of heterozygous PTEN loss and nuclear PTEN loss restored the normal size of brains and neurons. In contrast, the liver's size was unaffected by either single PTEN defects or their combination. Strikingly, the size of the inguinal lymph node was greatly increased due to lymphoma by the combination of the two PTEN defects. These data suggest that nuclear PTEN and non-nuclear PTEN function in an antagonistic manner in the brain while acting synergistically in the inguinal lymph node.

[A Case of Emphysematous Pyelonephritis Complicated by Bacterial Endophthalmitis in which Multidisciplinary Therapy Led to Preservation of the Kidney].

A 49-year-old male with untreated diabetes mellitus type 2 experienced eyesight deterioration and general malaise, and was treated for uveitis and orbital cellulitis. Later, he was taken to a local hospital via ambulance for a consciousness disorder and was diagnosed with bilateral infectious endophthalmitis, a right ureteral stone, and emphysematous pyelonephritis. He was then referred to our hospital for further examination and treatment. We immediately initiated intravenous antibiotic therapy with meropenem and glycemic control with continuous subcutaneous insulin infusion, and placed a ureteral and percutaneous drain tube into the right ureter and the emphysema, respectively. We performed a diagnostic and therapeutic vitrectomy on the patient's left eye. Urinary, blood, and vitreous cultures were positive for Klebsiella aerogenes. Abdominal contrast-enhanced computed tomography showed bilaterally comparable renal contrast enhancement. On the 60th hospital day, we performed endoscopic combined intrarenal surgery (ECIRS) and completely removed the urinary stone. Although he lost light sensitivity in his right eye, his left eyesight improved, and his blood glucose level was adequately managed by oral medication. Three months after the surgery, he was discharged from our hospital and he showed no sign of recurrence of the infection at ten months after surgery.

The Loss of Nuclear PTEN Increases Tumorigenesis in a Preclinical Mouse Model for Hepatocellular Carcinoma.

The PTEN gene is highly mutated in many cancers, including hepatocellular carcinoma. The PTEN protein is located at different subcellular regions-PTEN at the plasma membrane suppresses PI3-kinase signaling in cell growth, whereas PTEN in the nucleus maintains genome integrity. Here, using nuclear PTEN-deficient mice, we analyzed the role of PTEN in the nucleus in hepatocellular carcinoma that is induced by carcinogen and oxidative stress-producing hepatotoxin. Upon oxidative stress, PTEN was accumulated in the nucleus of the liver, and this accumulation promoted repair of DNA damage in wild-type mice. In contrast, nuclear PTEN-deficient mice had increased DNA damage and accelerated hepatocellular carcinoma formation. Both basal and oxidative stress-induced localization of PTEN in the nucleus require ubiquitination of lysine 13 in PTEN. Taken together, these data suggest the critical role of nuclear PTEN in the protection from DNA damage and tumorigenesis in vivo.

[A Case of Castration-Resistant Prostate Cancer after Prostatectomy Treated with Resection of A Solitary Metastatic Site].

A 72-year-old man underwent a bilateral nerve-sparing radical retropubic prostatectomy (RRP) with pelvic lymph node dissection 11 years earlier. His prostate specific antigen (PSA) value at diagnosis was 61.024 ng/ml. Bone scans and computed tomographic (CT) scans showed no metastasis. Pathological findings and stage were adenocarcinoma, Gleason score 4+3, positive surgical margin, pT3b, and no lymph node metastasis. The postoperative PSA nadir was 0.218 ng/ml, and salvage radiotherapy (SRT, total 66 Gy) was performed six months after RRP. However, the PSA value continued to rise after SRT. Therefore, androgen deprivation therapy (ADT) was started 11 months after SRT. Nine years postoperatively, the PSA value showed a continuous rise despite ADT, and prostate cancer was considered to be castration-resistant. Although he was taking enzalutamide, his PSA value rose to 18. 271 ng/ml. Repeated bone scans and CT scans were negative. Eleven years after RRP, the fluoro-2-deoxy-D-glucosepositronemissiontomography (FDG-PET) revealed a nodule lesiondorsal to the left pubic bone. The patient underwent a resection of the lesion. Three months after the resection, his PSA level declined to 0.038 ng/ml, thus ADT was discontinued. Thirteen months after the resection, PSA re-elevation was absent, and follow-up without ADT is ongoing.

Perineal recurrence of prostate ductal adenocarcinoma after transperineal brachytherapy: a case report and literature review.

Perineal recurrence after brachytherapy is an exceedingly rare complication. Moreover, ductal adenocarcinoma is a rare histological variant of prostate cancer. Herein, we describe a case of perineal recurrence from ductal adenocarcinoma of prostate after low-dose-rate brachytherapy (LDR-BT) in a 65-year-old male patient. The patient had localized prostate cancer, for which he received LDR-BT; however, he experienced perineal recurrence 2 years after receiving LDR-BT. Surgical excision was attempted, but we were unable to remove the whole tumor, owing to invasion to surrounding tissue. Pathological examination of resected tumor showed ductal adenocarcinoma of the prostate. External beam radiation therapy and high-dose-rate brachytherapy (HDR-BT) were performed for residual tumor. Mild mediastinal lymph node swelling was observed during clinical course of the disease. Hence, androgen deprivation therapy was administered with abiraterone after radiation therapy, and prostate-specific antigen level decreased to undetectable level. Biochemical failure after transperineal brachytherapy for prostate cancer should be considered as a perineal recurrence.

Placement of SpaceOAR hydrogel spacer for prostate cancer patients treated with iodine-125 low-dose-rate brachytherapy.

OBJECTIVES: The aim of the present study was to report on our early experience with hydrogel spacer (SpaceOAR) placement in combination with iodine-125 low-dose-rate brachytherapy for prostate cancer. METHODS: From April 2018, SpaceOAR hydrogel spacer was placed in 100 consecutive patients undergoing iodine-125 low-dose-rate brachytherapy. Complications and the status of the placement were evaluated. Deformation of the prostate by the spacer was examined measuring prostate diameters and evaluating the change from preoperative status. The position of the prostate was similarly examined by evaluating the change in distance between the pubic symphysis and the prostate. Post-plan dosimetric data were compared with 200 patients treated without a spacer. RESULTS: No complications were found during either the intraoperative or perioperative periods. The mean displacement distance of 11.64 mm was created, the mean value before spacer placement was 0.28 mm (P < 0.0001). The change of the prostate diameters showed a positive increase in all directions, with no significant negative change in any one direction. Regarding the change in distance between pubic symphysis and the prostate, no significant shortening trend was observed between the two groups (P = 0.14). Whereas the dosimetric parameters showed means of 0.001 and 0.026 cc for RV150 and RV100 in the spacer group, they were 0.025 and 0.318 cc, respectively, in the non-spacer group, showing a significant decrease in both parameters (P < 0.001). CONCLUSIONS: Prostate deformation secondary to hydrogel placement might adversely affect dosimetric parameters in patients undergoing low-dose-rate brachytherapy. However, a significant reduction in the rectal dose can be adopted without adversely affecting the other parameters related to treatment outcome.

[A Case of Transurethral Ureterolithotripsy Performed in a Morbidly Obese Patient with a Ureteral Stone].

Metabolic syndrome, such as obesity and hyperglycemia, are associated with kidney stones, and there is an association between body mass index (BMI) and urolithiasis. Treatment of urinary calculi in obese patients is not rare, but radiography images are often unclear. Here we report a case of a morbidly obese patient (BMI, 54 kg/m2) with a ureteral stone, who successfully underwent transurethral ureterolithotripsy (TUL). A 40-year-old man with gross hematuria visited a local doctor, and abdominal computed tomography (CT) showed a left kidney stone. He was admitted to another hospital, and abdominal CT showed a left ureteral stone. However, extracorporeal shock wave lithotripsy (ESWL) and TUL could not be performed because of poor quality radiography images. He was then admitted to our hospital for treatment. A left ureteral stent was placed 6 days before surgery. We successfully performed TUL using an operation table having a relatively high maximum load limit and using a high-voltage C-type arm radioscopy device. The findings in our case suggest that TUL can be successfully performed in morbidly obese patients by using appropriate operative tools.

Nuclear PTEN deficiency causes microcephaly with decreased neuronal soma size and increased seizure susceptibility.

Defects in phosphatase and tensin homolog (PTEN) are associated with neurological disorders and tumors. PTEN functions at two primary intracellular locations: the plasma membrane and the nucleus. At the membrane, PTEN functions as a phosphatidylinositol (3,4,5)-trisphosphate phosphatase and suppresses PI 3-kinase signaling that drives cell growth and tumorigenesis. However, the in vivo function of nuclear PTEN is unclear. Here, using CRISPR/Cas9, we generated a mouse model in which PTEN levels in the nucleus are decreased. Nuclear PTEN-deficient mice were born with microcephaly and maintained a small brain during adulthood. The size of neuronal soma was significantly smaller in the cerebellum, cerebral cortex, and hippocampus. Also, these mice were prone to seizure. No changes in PI 3-kinase signaling were observed. By contrast, the size of other organs was unaffected. Therefore, nuclear PTEN is essential for the health of the brain by promoting the growth of neuronal soma size during development.

[A Study of the Efficacy of the Additional Administration of Tadalafil in Japanese Men with α1-Blocker-Resistant LUTS/BPH].

Alpha 1-blockers are widely used at present for lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH). However, some patients experience little improvement of symptoms, and it is difficult to provide additional treatment. We have additionally administered tadalafil to patients with inadequate symptom improvement, despite treatment with alpha-1 blockers. The subjects were 57 patients with a diagnosis of LUTS/BPH who showed a poor response to treatment with alpha-1 blockers for 1 month or more (international prostate symptom score [IPSS] ≥8 and/or quality of life [QOL] index ≥3). Tadalafil 5 mg was administered on consecutive days to patients orally receiving alpha-1 blockers. We determined IPSS, the QOL index, overactive bladder symptom scores (OABSS), maximum urine flow, residual urine volume, and the sexual health inventory for men (SHIM) before, and 4, 8, and 12 weeks after administration, and then evaluated improvement effects. IPSS, the QOL index, OABSS, and SHIM showed significant improvement (P ＜0.05) at 4 weeks after the start of treatment and onward. IPSS and the QOL index showed greater improvement effects at 8 and 12 weeks. Residual urinary volume was significantly improved only at 8 weeks. However, the maximum urine flow showed no improvement at any time point. Our results demonstrated the additional administration of tadalafil to patients with LUTS showing poor responses to alpha-1 blockers to improve LUTS/BPH symptoms as well as sexual function.

EFFECT OF TADALAFIL THAT WAS ADDITIONALLY ADMINISTERED TO PATIENTS RECEIVING AN ALPHA1-BLOCKER IN JAPANESE MEN WITH LOWER URINARY TRACT SYMPTOMS SUGGESTIVE OF BENIGN PROSTATIC HYPERPLASIA.

(Objectives) Alpha1-blockers have been widely used for the treatment of lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH). As improvement of symptoms occur relatively early after the administration of alpha-1 blockers, the blockers are considered to be extremely beneficial. However, some patients respond poorly to the blockers, providing additional treatment is difficult. Here we examined the efficacy of tadalafil that was additionally administered to patients receiving an oral alpha-1 blocker. (Subjects and methods) The subjects were patients who had been diagnosed with BPH/LUTS, had received an oral alpha1-blocker for at least 1 month, and had responded poorly to the alpha-1 blocker treatment (International Prostate Symptom Score IPSS ≥8 and/or QOL index ≥3). Tadalafil 5 mg was administered on consecutive days to patients orally receiving an alpha-1 blocker. The following were measured before and at 4 and 8 weeks after the administration of tadalafil to evaluate the add-on effect of Tadalafil: IPSS, QOL index, Overactive Bladder Symptom Score (OABSS), maximal urinary flow rate, residual urine volume, and International Index of Erectile Function-5 (IIEF-5). (Results) We studied 41 patients until 8 weeks after the drug administration. Tadalafil produced significant improvement in IPSS, QOL index, OABSS, and IIEF-5 at 4 weeks after the administration, as compared with before administration (P < 0.05). The improvement was even more significant at 8 weeks. However, the maximal urinary flow rate or residual urine volume did not differ significantly at any time point. (Conclusions) The results of this study revealed that additional administration of tadalafil improves not only urinary conditions but also sexual function in patients with BPH/LUTS.

INITIAL EXPERIENCE OF THE ENZALUTAMIDE TREATMENT FOR CASTRATION-RESISTANT PROSTATE CANCER.

(Objective) Enzalutamide is an oral androgen-receptor inhibitor that prolongs survival in men with castration-resistant prostate cancer (CRPC). We retrospectively evaluated clinical efficacy and safety of enzalutamide in CRPC. (Patients and methods) We reviewed clinical records of 73 patients who had received enzalutamide for the CRPC at Showa University and affiliated 7 hospitals. Enzalutamide was given at a dose of 160 mg/day, but some patients were treated at lower dose because of there age or poor performance status. Prostrate-specific antigen (PSA) response, prior docetaxel use and the previously administered agents were evaluated retrospectively. (Results) The median patients age was 77 years, the median Gleason score was 9 and the median PSA level at baseline was 26.9 ng/ml. The patients who had prior docetaxel use were 29 (39.7%) and the median of total docetaxel dose was 460 mg/body. The median number of total prior treatments (anti-androgens, Estramustine and steroid) was 3. Twenty seven (61.4%) patients with docetaxel-naïve achieved over 50% reduction of PSA level from baseline, but only 7 (24.1%) in patients previously treated with docetaxel. The most common adverse events included fatigue (24.7%), anorexia (24.7%) and the nausea (16.4%). We found a small proportion of responders to enzalutamide experienced a PSA flare. (Conclusion) Our results of the use of Enzaltamide for CRPC were similar with previous reports. PSA flare was found in some patients with CRPC who responded to enzaltamide. It should be noted that this possible PSA flare phenomenon.

[A CASE OF PROSTATE CANCER WITH UNUSUAL PATTERN OF RECURRENCE AFTER RADIOTHERAPY].

An 82-year-old man underwent radiotherapy (brachytherapy, external beam radiotherapy) for prostate cancer, followed approximately five years later by endocrine therapy for biochemical recurrence, which controlled the prostate-specific antigen (PSA) level. His later admission due to severe gross hematuria and dysuria is described. Computed tomography and magnetic resonance imaging findings revealed a cystic tumor continuous with the prostate between the prostate and rectum, and this tumor was thought to be the cause of the hematuria and dysuria. Transrectal biopsy and transurethral resection of the prostate were performed for pathological diagnosis and improvement of dysuria. The pathological diagnosis was remnant prostate cancer, and the cystic tumor was thought to have developed as a result of prostate cancer recurrence. Although chemotherapy using docetaxel was considered postoperatively, the patient refused this treatment. Even though the PSA level was under control, the patient's condition progressed rapidly, with onset of pulmonary and cervical lymph node metastases within a short period of time, and the patient subsequently died.

[Testicular tumor with opposite inguinal lymph node metastasis in a patient with prior orchiopexy for undescended testis].

The patient was a 54-year-old man. At age 6 years, he had undergone orchiopexy for left undescended testis. Six months prior to the current presentation, he visited our hospital with a chief complaint of painless enlargement of the left testis. Left high orchiectomy was performed under a diagnosis of left testicular tumor. Histopathological examination determined the tumor to be a seminoma (pT2). Postoperatively, the patient was placed on surveillance without preventive radiation treatment. He visited our hospital six months after surgery due to a painless mass in the right inguinal region. All tumor markers (AFP, HCG-ß, and LDH) were within normal ranges. However, based on ultrasound and CT scan findings, lymph node metastasis was suspected and a right inguinal lymph node excision was thus performed. Histopathological examination led to the diagnosis of seminoma.

Synthesis and structural analysis of (imido)vanadium(V) dichloride complexes containing imidazolin-2-iminato- and imidazolidin-2-iminato ligands, and their use as catalyst precursors for ethylene (co)polymerization.

A series of (imido)vanadium(V) dichloride complexes containing 1,3-imidazolin-2-iminato or 1,3-imidazolidin-2-iminato ligands of the type, V(NR')Cl2(L) [R' = 2,6-Me2C6H3, L = 1,3-R2(CHN)2C═N (1a-c,e) or 1,3-R2(CH2N)2C═N (2a-d), R = (t)Bu (a), 2,6-Me2C6H3 (b), 2,6-(i)Pr2C6H3 (c), C6H5 (d), 2,6-(Ph2CH)2-4-MeC6H2 (e); L = 1,3-(2,6-(i)Pr2C6H3)2(CHN)2C═N, R' = 1-adamantyl (Ad, 3c), C6H5 (4c); L = 1,3-(2,6-(i)Pr2C6H3)2(CH2N)2C═N, R' = Ad (5c)], were prepared and characterized. The molecular structures of 1a, 2a,c,d, 3c, 4c, and 5c were determined by X-ray crystallography. All complexes showed high catalytic activity for ethylene polymerization especially in the presence of Et2AlCl cocatalyst; the 2,6-R2C6H3 analogues (R = Me, (i)Pr; 1b,c, 2b,c) exhibited higher catalytic activities than the (t)Bu analogues (1a, 2a), which display rather unique (small) V-N-C(imido) bond angles in the solid state. A good correlation between the activity and the (51)V NMR chemical shift was found for the (arylimido)vanadium precatalysts (1a-c,e, 2a-d, and 4c). These complexes showed high catalytic activity for the copolymerization of ethylene with norbornene (NBE), affording ultrahigh molecular weight copolymers with uniform molecular weight distributions. The activities were affected by the imido ligand as well as by the substituents in the anionic ligand, and the 2,6-(i)Pr2C6H3 analogues (especially 2c and 4c) showed the higher activities. The complexes 2c and 4c also showed high activities with efficient comonomer incorporation for the ethylene copolymerization with 5-ethylidene-2-norbornene (ENB) in the presence of Et2AlCl; both the comonomer incorporation and the molecular weight in the resulting polymers were affected by the comonomer employed (NBE vs ENB).

Synthesis and structural analysis of (imido)vanadium(V) complexes containing chelate (anilido)methyl-imine ligands: ligand effect in ethylene dimerization.

A series of (imido)vanadium dichlorido complexes containing chelate anionic donor ligands of the type, VCl2(L)(NR) [R = 1-adamantyl (Ad), L = 2-(2,6-Me2C6H3)NCH2(C9H6N) (2), 8-(2,6-Me2C6H3)NCH2(C9H6N) (3); L = 2-(2,6-R'2C6H3)NCH2(C5H4N), R = 2-MeC6H4, R' = Me (4a), (i)Pr (4b); L = 2-(2,6-Me2C6H3)NCH2(C5H4N), R = 4-MeC6H4 (5), 3,5-Me2C6H3 (6)], have been prepared and identified. The reactions with ethylene by 2,3 in the presence of methylaluminoxane (MAO) afforded a mixture of high molecular weight polyethylene and oligomers. Reactions with ethylene by VCl2[2-(2,6-R'2C6H3)NCH2(C5H4N)](NAd) (1a,b), 4-6 afforded 1-butene with high selectivities (>92%), and the activities by 4a,b are at the same level as those in 1a,b. The activities by 5,6 were lower than 4a,b and were at the same level of that by VCl2[2-(2,6-Me2C6H3)NCH2(C5H4N)](NPh). These results thus suggest that both the chelate anionic donor and the imido ligands play a role for both the activity and the selectivity.

Enhancement of IL-2-induced cytotoxicity by interferon-alpha in renal cell carcinoma.

Metastatic renal cell carcinoma (mRCC) treatment consists of molecular targeted agents and cytokines that have fundamentally different mechanisms of action. Clinical responses also differ; complete response is rare with molecular targeted agents but is sometimes achieved with cytokine therapies. Because of the relatively high efficacy of combination therapy with low-dose interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) against mRCC, it is important to reevaluate cytokine therapies in vitro. Here, we show that when IL-2 is administered in combination with IFN-alpha, a stronger cytotoxic effect of PBMCs on RCC cell lines is observed than when IL-2 is administered alone. The upregulation of TNF-related apoptosis-inducing ligand on NK cell by IL-2 and suppression of regulatory T cells (Tregs) by IFN-alpha were recognized at the same time when cytotoxicity of peripheral blood mononuclear cells (PBMCs) was enhanced. IL-2 is known to activate natural killer cell cytotoxicity; however, IL-2 also stimulates Treg expansion, which enhances immunosuppression. On the other hand, IFN-alpha negatively regulates Treg cells, thereby increasing the function of immune effector cells. Our in vitro results may explain, at least in part, the clinical efficacy of combination low-dose IL-2 and IFN-alpha therapy against mRCC.