Update on systemic therapies of metastatic renal cell carcinoma

Progression-free survival of first-line treatment with molecular-targeted therapy may be a meaningful intermediate endpoint for overall survival in patients with metastatic renal cell carcinoma

The aim of the present study was to investigate the association between clinical parameters and the overall survival (OS) of Japanese patients with metastatic renal cell carcinoma (mRCC). The medical records of 59 consecutive mRCC patients receiving molecular-targeted therapy were retrospectively assessed. Kaplan-Meier and log-rank analyses were used to evaluate the progression-free survival (PFS) and OS, and a multivariate Cox proportional hazard model was used to analyze the clinical parameters for their prognostic relevance. The median OS for all patients was 23.7 months [95% confidence interval (CI): 17.9-30 months], and the median OS stratified by the Memorial Sloan Kettering Cancer Center risk classification was 28.5, 20.9 and 8.1 months for the favorable-, intermediate- and poor-risk groups, respectively (P=0.137; degree of freedom: 2). Univariate analyses identified prior nephrectomy, number of metastatic sites, anemia, best response to first-line treatment and PFS with first-line treatment as prognostic variables. Multivariate analyses identified number of metastatic sites [2: hazard ratio (HR)=3.351, 95% CI: 1.460-8.201, P=0.004; ≥3: HR=6.397, 95% CI: 1.939-20.209, P=0.003], time from diagnosis to therapy (≥1 year: HR=0.334, 95% CI: 0.137-0.755, P=0.008), PFS with first-line treatment (≥5.1 months: HR=0.353, 95% CI: 0.156-0.766, P=0.008) and number of lines of molecular-targeted agents (≥3: HR=0.248, 95% CI: 0.091-0.664, P=0.006) as independent prognostic factors. The results indicated that the PFS of first-line treatment may be a meaningful intermediate endpoint for OS in patients with mRCC who received treatment with molecular-targeted therapy.

Efficacy and toxicity of sunitinib in metastatic renal cell carcinoma patients in Egypt

BACKGROUND

To evaluate our results in terms of response, survival and toxicity profile of sunitinib among Egyptian patients with metastatic renal cell carcinoma.

MATERIALS AND METHODS

Between January 2010 and December 2013, 44 patients with metastatic renal cell carcinoma who received sunitinib at an oncology center of Cairo university hospitals were enrolled in this retrospective analysis.

RESULTS

The median age of the patients was 53 years, 22 (50%) having localized disease at presentation ,while the remaining half of the patients presented with metastasis. At a median follow up of 19 months, 9 (21%) patients achieved partial remission, while disease was reported stable in 20 cases (45%) and progressive in 7 (16%), 4 (9%) being lost to follow up, and 4 (9%) had discontinued therapy due to toxicity. The median overall survival was 23 months (95%CI 15.2 - 30.9), while progression free survival was 12 months (95%CI 11.6 - 12.3). The most commonly reported non hematological grade 3 adverse events included mucositis (15.9%), hand-foot syndrome (13.6%), and fatigue (9%), while the predominant grade 3 or 4 laboratory abnormalities were neutropenia (6.8%), followed by anemia in 4.5% of patients.

CONCLUSIONS

Our efficacy data were comparable to the published literature in terms of progression free survival and overall survival , while toxicity profile is different from Asian and western countries. However, sunitinib adverse events were manageable and tolerable in most of our Egyptian patients.

The anti-tumor effect of a polypeptide extracted from Tegillarca granosa Linnaeus on renal metastatic tumor OS-RC-2 cells

INTRODUCTION

Renal cell carcinoma is a type of malignant tumor often diagnosed in the urinary system. The aim of this study is to evaluate the anti-tumor effects and mechanisms of a polypeptide, Haishengsu (TG-1), with different concentrations (125, 250, 500 mg/kg) on renal metastatic tumor OS-RC-2 cells.

MATERIAL AND METHODS

We first established the renal metastatic tumor model. After being administered with TG-1, the weight of tumors was measured and the microstructural changes of renal carcinoma OS-RC-2 cells were compared using transmission electron microscopy before and after the therapy. The Ki67 expression in renal carcinoma OS-RC-2 cells was analyzed by RT-PCR and downstream signal molecule caspase-3 was measured by Western blot assay.

RESULTS

After treatment with different doses of TG-1, the tumor weights in the positive control group and experimental groups were smaller than those in the untreated control group, suggesting that TG-1 could effectively inhibit tumor growth in mice. The transmission electron microscopy and flow cytometry results indicated that TG-1 induces tumor cell apoptosis (p < 0.05). The tumor cells exhibited polymorphism changes and chromatin edge clustering. TG-1 also inhibited Ki67 expression and promoted caspase-3 expression in the tumor significantly (p < 0.05).

CONCLUSIONS

TG-1 inhibits the growth of the tumor and induces apoptosis of the tumor cells by inducing caspase-3 expression. The results provide a basis for clinical application of TG-1 in the future.

Surgery and survival outcomes of 30 patients with neurological deficit due to clear cell renal cell carcinoma spinal metastases

PURPOSE

The aim of this study was to provide some useful insights into the clinical and imaging presentations, treatment and prognostic factors in patients with neurological deficit caused by clear cell renal cell carcinoma (CCRCC) spinal metastases for the sake of designing individualized therapeutic plans for such patients.

METHODS

A total of 30 patients with neurological deficit due to CCRCC spinal metastases who received surgery in our department were identified during an 8-year period from 2003 to 2012 and used for discussion of treatment options for CCRCC spinal metastases on the basis of literature review and our own experience.

RESULTS

Univariate analysis showed that age (≤45 years/>45 years), visceral metastasis, Tomita score (3-5/6-8), Tokuhashi score (4-9/10-12) and radiotherapy were suggested as the potential prognostic factors. However, the multivariate Cox regression model showed that only Tokuhashi score was an independent prognostic factor.

CONCLUSIONS

Tokuhashi score 10 or more is a favorable prognostic factor of CCRCC spinal metastasis.

Enhanced sensitivity to sorafenib by inhibition of Akt1 expression in human renal cell carcinoma ACHN cells both in vitro and in vivo

To investigate whether antitumor activity of sorafenib, a potential molecular-targeted agent against RCC is enhanced by silencing Akt1 in a human RCC ACHN model. We established ACHN in which the expression vector containing short hairpin RNA targeting Akt1 was introduced (ACHN/sh-Akt1). Changes in several phenotypes of ACHN/sh-Akt1 following treatment with sorafenib were compared with those of ACHN transfected with control vector alone (ACHN/C) both in vitro and in vivo. When cultured in the standard medium, there was no significant difference in the in vitro growth pattern between ACHN/sh-Akt1 and ACHN/C; however, compared with ACHN/C, ACHN/sh-Akt1 showed a significantly higher sensitivity to sorafenib. Furthermore, treatment with Akt1 inhibitor, A-674563 also resulted in the significantly enhanced sensitivity of parental ACHN to sorafenib. Treatment of ACHN/sh-Akt1 with sorafenib, but not that of ACHN/C, induced marked downregulation of antiapoptotic proteins, including Bcl-2, Bcl-xL, and c-Myc. In vivo administration of sorafenib resulted in the significant growth inhibition of ACHN/sh-Akt1 tumor compared with that of ACHN/C tumor, and despite the lack of Ki-67 labeling index between ACHN/sh-Akt1 and ACHN/C tumors, apoptotic index in ACHN/sh-Akt1 tumor in mice treated with sorafenib was significantly greater than that in ACHN/C tumor. These findings suggest that combined treatment with Akt1 inhibitor and sorafenib could be a promising therapeutic approach for patients with advanced RCC.

Targeted therapies in advanced renal cell carcinoma: the role of metastatic sites as a prognostic factor

AIM

This retrospective study evaluates whether metastatic sites were associated with progression-free survival (PFS) and overall survival (OS) in patients with renal cell carcinoma treated with targeted therapies.

PATIENTS & METHODS

In total, 358 patients were analyzed.

RESULTS & CONCLUSION

After a median follow-up of 56.1 months, median PFS was 11 months and median OS was 24.2 months. Metastatic sites were associated with PFS: lymph nodes (HR: 1.43; 95% CI: 1.12-1.83; p = 0.004), liver (HR: 1.41; 95% CI: 1.05-1.90; p = 0.021), bone (HR: 1.26; 95% CI: 0.96-1.65; p = 0.091), brain (HR: 0.81; 95% CI: 0.46-1.43; p = 0.474) and other sites (HR: 1.07; 95% CI: 0.83-1.38; p = 0.589). Metastatic sites were associated with OS: lymph nodes (HR: 1.73; 95% CI: 1.31-2.29; p < 0.001), liver (HR: 1.71; 95% CI: 1.23-2.37; p = 0.002), bone (HR: 1.48; 95% CI: 1.10-1.98; p = 0.009), brain (HR: 1.21; 95% CI: 0.64-2.28; p = 0.568) and other sites (HR: 1.09; 95% CI: 0.81-1.47; p = 0.568). Patients with >2 metastatic sites had shorter PFS and OS. Every association was lost when introducing the Motzer score in regression models.

A Synchronous Pancreatic Metastasis from Renal Clear Cell Carcinoma, with Unusual CT Characteristics, Completely Regressed after Therapy with Sunitinib

We present a case report of a 75-years-old woman affected by renal clear cell carcinoma with a synchronous pancreatic metastasis and a metachronous lung metastasis. This case has two peculiarities. First the pancreatic metastasis was treated just with medical therapy, that is, Sunitinib, instead of the surgical therapy that is mostly considered. Secondly, the pancreatic lesion showed different characteristics on the computed tomography scan compared to the usual pancreatic metastases from renal clear cell carcinoma. The pancreatic metastasis totally regressed after medical treatment and nowadays, four years after the diagnosis, the patient is disease-free.

Chest X-ray in the follow-up of renal cell carcinoma

PURPOSE

To evaluate the value of chest X-ray in the follow-up of surgically treated T1-3N0M0 renal cell carcinoma.

METHODS

We performed retrospective analysis of patients that underwent surgical treatment of a localized renal cell carcinoma (T1-3N0M0) between January 1993 and July 2010. Data on frequency and results of performed chest X-rays were collected from patients' records.

RESULTS

In 17.5 years, 249 patients with a T1-3N0M0 renal cell carcinoma underwent a radical or partial nephrectomy. In 221 patients, 823 chest X-rays were performed during a median follow-up of 3.3 years (range 0.5-17 years). In 19 patients, a pulmonary recurrence occurred, of which 10 were not detected by the regular follow-up. Of the 9 patients that were diagnosed with a pulmonary recurrence with a chest X-ray during follow-up, 7 were asymptomatic at the time of diagnosis, and the chest X-ray has led to the detection; 0.85 % of the performed chest X-rays (7/823) have led to the detection of asymptomatic lung metastases.

CONCLUSIONS

Due to the low yield of chest X-ray for detection of asymptomatic pulmonary recurrences, it has very low clinical value in the follow-up after nephrectomy for T1-3N0M0 renal cell carcinoma.

Current and future treatments for malignant pheochromocytoma and sympathetic paraganglioma

Pheochromocytomas (PHs) and sympathetic paragangliomas (SPGs) are rare neuroendocrine tumors. Approximately 17 % of these tumors are malignant, but because no molecular or histologic markers for malignancy exist, patients are often diagnosed with malignant PHs or SPGs after unresectable disease has formed. Patients with progressive metastatic tumors and overwhelming symptoms are currently treated with systemic chemotherapy and radiopharmaceutical agents such as metaiodobenzylguanidine. These therapies lead to partial radiographic response, disease stabilization, and symptomatic improvement in approximately 40 % of patients, and systemic chemotherapy is associated with a modest improvement in overall survival duration. However, over the past decade, substantial progress has been made in clinical, biochemical, and radiographic diagnosis of PHs and SPGs. Approximately 50 % of patients with malignant PHs and SPGs have been found to carry hereditary germline mutations in the succinate dehydrogenase subunit B gene (SDHB), and anti-angiogenic agents such as sunitinib have been found to potentially play a role in the treatment of malignant disease, especially in patients with SDHB mutations. In some patients, treatment with sunitinib has been associated with partial radiographic response, disease stabilization, decreased fluorodeoxyglucose uptake on positron emission tomography, and improved blood pressure control. These findings have led to the development of prospective clinical trials of new targeted therapies for metastatic disease. Here, we provide an updated review of the clinical and genetic predictors of malignant disease, radiographic diagnosis of malignant disease, and information from the most relevant studies of systemic therapies, as well as proposed treatment guidelines for patients with metastatic or potentially malignant PHs and SPGs.

Simvastatin inhibits renal cancer cell growth and metastasis via AKT/mTOR, ERK and JAK2/STAT3 pathway

Renal cell carcinoma (RCC) is the most lethal type of genitourinary cancer due to its occult onset and resistance to chemotherapy and radiation. Recently, accumulating evidence has suggested stains, inhibitors of 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase, were associated with the risk reduction of cancer. In the present study, we aimed to investigate the potential effects of simvastatin on RCC cells and the underlying mechanisms by which simvastatin exerted its actions. With cell viability, colony formation, and flow cytometric apoptosis assays, we found that simvastatin potently suppressed cell growth of A498 and 786-O cells in a time- and dose- dependent manner. Consistently, the xenograft model performed in nude mice exhibited reduced tumor growth with simvastatin treatment. In addition, the inhibitory effects of simvastatin on migration and invasion were also observed in vitro. Mechanically, we presented that simvastatin could suppress the proliferation and motility of RCC cells via inhibiting the phosphorylation of AKT, mTOR, and ERK in a time- and dose- dependent manner. Further investigation of the underlying mechanism revealed simvastatin could exert the anti-tumor effects by suppressing IL-6-induced phosphorylation of JAK2 and STAT3. In conclusion, these findings suggested that simvastatin-induced apoptosis and its anti-metastasis activity in RCC cells were accompanied by inhibition of AKT/mTOR, ERK, and JAK2/STAT3 pathways, which imply that simvastatin may be a potential therapeutic agent for the treatment of RCC patients.

Treatment of patients with metastatic renal cell carcinoma undergoing hemodialysis: case report of two patients and short literature review

Background

Renal cell carcinoma (RCC) may involve both kidneys. When bilateral nephrectomy is necessary renal replacement therapy is mandatory. Treating such patients with sequential therapy based on cytokines, antiangiogenic factors and mammalian target of rapamycin (mTOR) inhibitors is challenging.

Case presentation

The first case, a 50-year-old Caucasian female, underwent a radical right nephrectomy for RCC. Twelve years later she underwent a radical left nephrectomy along with total hysterectomy including bilateral salpingo-oophorectomy for RCC involving the right kidney and ovary. Hemodialysis was necessary because of bilateral nephrectomy. She relapsed with pulmonary metastases and enlarged mediastinal lymph nodes and received cytokine based therapy along with bevacizumab. Therapy was discontinued despite the partial response because of hemorrhagic gastritis. Therapy was switched to an antiangiogenic factor but the patient manifested a parietal brain hematoma and stopped therapy. Subsequently disease relapsed with malignant pleural effusion and pulmonary nodules and a mammalian target of rapamycin inhibitor was administered which was withdrawn only at patient’s deteriorating performance status. The patient died of the disease 13 years after the initial diagnosis of RCC.

The second case, a 51-year-old, Caucasian male, underwent a radical right nephrectomy for a chromophobe RCC. Six months later he underwent a radical left nephrectomy for RCC that proved to be a clear cell RCC. Due to bilateral nephrectomy hemodialysis was obligatory. Following disease recurrence at the anatomical bed of the right kidney therapy with antiangiogenic factor was administered which led to disease regression. However the patient experienced a left temporal-occipital brain hematoma. A radical excision of the recurrence which histologically proved to be a chromophobe RCC was not achieved and the patient received mTOR inhibitor which led to disease complete response. Nine years after the initial diagnosis of RCC he is disease free and leads an active life.

Conclusion

Patients with RCC are in significant risk to manifest bilateral disease. Renal insufficiency requiring hemodialysis poses therapeutic challenges. Clinicians must be aware of the antiangiogenic factors’ adverse effects, especially bleeding, that may manifest in higher frequency and more severe in this setting.

Acquired resistance to sunitinib in human renal cell carcinoma cells is mediated by constitutive activation of signal transduction pathways associated with tumour cell proliferation

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Although there have been a few studies investigating the molecular mechanism mediating the acquisition of resistance to molecular-targeted agents, including sunitinib, by renal cell carcinoma (RCC) cells, this mechanism remains largely unclear. The maintenance of protein kinase activation during sunitinib treatment may be involved in the acquisition of a phenotype resistant to sunitinib in RCC, and additional treatment with agents targeting activated protein kinases could be a promising approach for overcoming resistance to sunitinib in RCC.

OBJECTIVE

To characterise the mechanism involved in the acquired resistance to sunitinib, a potential inhibitor of multiple receptor tyrosine kinases (RTKs), in renal cell carcinoma (RCC).

MATERIALS AND METHODS

A parental human RCC cell line, ACHN (ACHN/P), was continuously exposed to increasing doses of sunitinib, and a cell line resistant to sunitinib (ACHN/R), showing an ≈5-fold higher IC50 (concentration that reduces the effect by 50%) than that of ACHN/P, was developed.

RESULTS

ACHN/R appeared to acquire significant cross resistance to sorafenib; however, there were no significant differences in sensitivities to the Mammalian target of rapamycin inhibitors, temsirolimus and everolimus, between ACHN/P and ACHN/R. After sunitinib treatment, the expression levels of phosphorylated Akt and p44/42 mitogen-activated protein kinase in ACHN/P, but not those in ACHN/R, were significantly inhibited. RTK assay showed that treatment of ACHN/P with sunitinib resulted in the marked downregulation of several phosphorylated RTKs compared with that of ACHN/R. Additional treatment with a specific inhibitor of Akt significantly increased the sensitivity of ACHN/R to sunitinib, but not that of ACHN/P. There were no significant differences between in vivo growth patterns of ACHN/P and ACHN/R in mice before and after the administration of sunitinib; however, the proportion of cells positive for TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling) staining in ACHN/P tumour was significantly greater than that in ACHN/R tumour in mice treated with sunitinib.

CONCLUSION

The maintenance of protein kinase activation during sunitinib treatment may be involved in the acquisition of resistant phenotype to sunitinib in RCC cells.

Treatment with sunitinib for patients with progressive metastatic pheochromocytomas and sympathetic paragangliomas

CONTEXT

Patients with progressive metastatic pheochromocytomas (PHEOs) or sympathetic paragangliomas (SPGLs) face a dismal prognosis. Current systemic therapies are limited.

OBJECTIVES

The primary end point was progression-free survival determined by RECIST 1.1 criteria or positron emission tomography with [(18)F]fluorodeoxyglucose/computed tomography ([(18)F]FDG-PET/CT), in the absence of measurable soft tissue targets. Secondary endpoints were tumor response according to RECIST criteria version 1.1 or FDG uptake, blood pressure control, and safety.

DESIGN

We conducted a retrospective review of medical records of patients with metastatic PHEO/SPGL treated with sunitinib from December 2007 through December 2011. An intention-to-treat analysis was performed.

PATIENTS AND SETTING

Seventeen patients with progressive metastatic PHEO/SPGLs treated at the Institut Gustave-Roussy and MD Anderson Cancer Center.

INTERVENTIONS

Patients treated with sunitinib.

RESULTS

According to RECIST 1.1, eight patients experienced clinical benefit; three experienced partial response, and five had stable disease, including four with predominant skeletal metastases that showed a 30% or greater reduction in glucose uptake on [(18)F]FDG-PET/CT. Of 14 patients who had hypertension, six became normotensive and two discontinued antihypertensives. One patient treated with sunitinib and rapamycin experienced a durable benefit beyond 36 months. The median overall survival from the time sunitinib was initiated was 26.7 months with a progression-free survival of 4.1 months (95% confidence interval = 1.4-11.0). Most patients who experienced a clinical benefit were carriers of SDHB mutations.

CONCLUSION

Sunitinib is associated with tumor size reduction, decreased [(18)F]FDG-PET/CT uptake, disease stabilization, and hypertension improvement in some patients with progressive metastatic PHEO/PGL. Prospective multi-institutional clinical trials are needed to determine the true benefits of sunitinib.

Prolonged survival after sequential multimodal treatment in metastatic renal cell carcinoma: two case reports and a review of the literature

INTRODUCTION

In this case series and short review of the literature, we underline the impact of nephrectomy combined with sequential therapy based on cytokines, antiangiogenic factors, and mammalian target of rapamycin inhibitors along with metastasectomy on overall survival and quality of life in patients with metastatic clear cell renal carcinoma.

CASE PRESENTATION

In the first of two cases reported here, a 53-year-old Caucasian man underwent a radical left nephrectomy for renal cell cancer and relapsed with a bone metastasis in his right humerus. He was treated with closed nailing and cytokine-based chemotherapy. For 5 years, the disease was stable and he had great improvement in quality of life. Subsequently, the disease relapsed in his lymph nodes, lung, and thorax soft tissue. He was then treated with antiangiogenic factors and mammalian target of rapamycin inhibitors. The disease progressed until September 2009, when he died of allergic shock during a blood transfusion, 9 years after the initial diagnosis of renal cell cancer.In the second case, a 54-year-old Caucasian man underwent a radical left nephrectomy for renal cell cancer. A year later, the disease progressed to his neck lymph nodes, and cytokine-based chemotherapy was initiated. While he was on cytokines, a solitary pulmonary nodule appeared and he underwent a metastasectomy. Nine months later, magnetic resonance imaging of his brain revealed a focal right occipitoparietal lesion, which was resected. After two years of active surveillance, the disease relapsed as a pulmonary metastasis and he was treated with an antiangiogenic factor. Further progressions presenting as enlarged axillary lymph nodes, chest soft tissue lesions, and thoracic spine bone metastases were sequentially observed. He then received a first-generation mammalian target of rapamycin inhibitor, an antiangiogenic factor, and later a second-generation mammalian target of rapamycin inhibitor and palliative radiotherapy. Ten years after the initial diagnosis of renal cell cancer, his disease is stable and he is on a third antiangiogenic factor and leads an active life.

CONCLUSIONS

One multidisciplinary approach to patients with metastatic renal cell cancer combines nephrectomy, metastasectomy, and radiotherapy (when feasible) with medical therapy based on cytokines and targeted treatment employing agents inhibiting angiogenesis, other receptor tyrosine kinases, and mammalian target of rapamycin. This approach could prolong survival and improve quality of life.

Pancreatic metastasis from renal cell carcinoma

BACKGROUND

Pancreatic metastases from renal cell carcinoma are uncommon.

METHODS

Retrospective study of 8 patients with a diagnosis of pancreatic metastasis from renal cell carcinoma observed in our Institute.

RESULTS

Patients were 6 (75%) males and 2 (25%) females. Mean age was 65.3 years. In 5 patients (57.1%), symptoms were present. The median interval of onset from nephrectomy was 10 years. No cases of synchronous pancreatic metastases were observed. Surgical resection was performed in 7 (87.5%) patients. At pathological examination, solitary metastases were identified in 5 patients (71.4%). No post-operative mortality was observed; the morbidity rate was 42.8%. In the group of patients who underwent pancreatic resection, median overall survival was 43.0 months (range 12.9-74.5), median disease-free survival was 23.6 months (range 9.9-74.5).

CONCLUSIONS

Pancreatic metastasis from renal cell carcinoma typically occurs after a long period from the initial nephrectomy, and seems to be related to a good prognosis.

Evaluation of treatment response in patients with metastatic renal cell carcinoma: role of state-of-the-art cross-sectional imaging

Recent advances in genetics and oncology have led to development of a wide array of molecular therapeutics in the management of patients with metastatic renal cell carcinoma. These drugs have revolutionized the treatment of advanced disease by significantly improving patient outcomes. State-of-the-art cross-sectional imaging techniques play a seminal role in the evaluation of treatment response by providing reproducible, objective data, thereby permitting accurate quantification of tumor burden. Evolving functional imaging techniques such as perfusion and diffusion studies continue to advance the technology beyond assessing changes in tumor size and morphology.

Tyrosine kinase expression profile in clear cell renal cell carcinoma

PURPOSE

To profile different tyrosine kinase (TK) expression patterns in clear cell renal carcinoma (ccRCC).

METHODS

We analysed mRNA expression levels of 89 receptor and non-receptor TK in corresponding cancer and normal renal tissue from 5 patients with ccRCC using the TaqMan Low-Density Array technology. In order to confirm aberrant TK expressions, a subsequent analysis of 25 ccRCC and corresponding normal renal tissues was performed, applying quantitative real-time PCR. To confirm mRNA expression levels on protein level, we studied ERBB4 and HCK using immunohistochemistry.

RESULTS

A total of 12 TK were significantly upregulated in ccRCC (ABL2, FLT1, BTK, HCK, JAK3, CSF1R, MET, JAK1, MATK, PTPRC, FYN and CSK), coherently 7 TK demonstrated a down-regulation (ERBB4, PDGFRA, NRTK3, SYK, ERBB2, FGFR3 and PTK7). These findings were validated by the utilization of RT-PCR for ABL2, FLT1 BTK, HCK, JAK3, CSF1R, MET, JAK1, MATK and vice versa for ERBB4 and PDGFRA. Immunohistochemistry revealed ERBB4 expression to be significantly lower in ccRCC in comparison to papillary RCC, chromophobe RCC, renal oncocytoma and normal renal tissue (P < 0.001). HCK protein expression was reduced in ccRCC in contrast to papillary RCC (P < 0.001) or oncocytoma (P = 0.023), but similar to chromphobe RCC (P = 0.470), sarcomatoid RCC (P = 0.754) and normal renal tissue (P = 0.083). Neither ERBB4 nor HCK were correlated (P > 0.05) with clinical-pathological parameters.

CONCLUSION

TK constitute valuable targets for pharmaceutical anti-cancer therapy. ERBB4 and HCK depict significantly lower expression levels in renal cancer tissues.

Long-term complete response to very-low-dose interleukin-2 therapy in patients with metastatic renal cell carcinoma: report of two cases

Before the advent of molecular-targeted agents, immunotherapy using cytokines, such as interferon-α (IFN-α) and interleukin-2 (IL-2), had been the mainstay of treatment for patients with metastatic renal cell carcinoma (mRCC), and this therapy may still be occasionally recommended for such patients. In this report, we present two cases of mRCC who were treated with very-low-dose IL-2 therapy and subsequently achieved complete response (CR). Both cases received adjuvant IFN-α therapy following radical nephrectomy; however, multiple lung metastases developed 4 and 12 months after surgery, and low-dose IL-2 (0.7 million U/day) was then administered twice per week for 14 and 35 months, respectively. In both cases, metastatic lesions completely regressed 3 and 20 months after the start of IL-2 therapy, and these responses have persisted for 81 and 67 months, respectively, to date. These findings suggest that immunotherapy with IL-2, even at a very-low-dose setting, may achieve the induction of CR in mRCC; accordingly, IL-2-based immunotherapy should be considered as the initial treatment for appropriately selected patients with mRCC.

Metformin inhibits renal cell carcinoma in vitro and in vivo xenograft

OBJECTIVE

To evaluate the effects of metformin on renal cell carcinoma (RCC) and its underlying mechanisms.

MATERIALS AND METHODS

We used 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and colony formation assays to investigate the effects of metformin on RCC cell growth. Flow cytometry was used to evaluate the cell cycle changes after metformin treatment. We further determined the possible signaling molecules involved in this process by immunoblot analysis of various proteins. Furthermore, a xenograft model was used to study the effects of metformin on RCC tumor growth.

RESULTS

We demonstrated that metformin effectively inhibits cell proliferation in 786-O and OS-RC-2 RCC cell lines. Moreover, metformin down-regulated cyclin D1 expression and induced G0/G1 cell cycle arrest in these cells. Further study revealed metformin induced the activation of AMP-activated protein kinase (AMPK), and inhibited mammalian target of rapamycin (mTOR), which is a central regulator of protein synthesis and cell growth, and negatively regulated by AMPK. Most importantly, daily treatment of mice with metformin prevented RCC tumor growth in a xenograft model.

CONCLUSIONS

Metformin was able to induce G0/G1 cell cycle arrest and inhibit RCC growth in vitro and in vivo. These results suggest that metformin may be a potential therapeutic agent for the treatment of RCC.

Silibinin inhibits the invasion and migration of renal carcinoma 786-O cells in vitro, inhibits the growth of xenografts in vivo and enhances chemosensitivity to 5-fluorouracil and paclitaxel

Silibinin is a flavonoid antioxidant that is widely used for its anti-hepatotoxic properties. It exerts a dose-dependent inhibition on the invasion and migration of 786-O renal cell carcinoma (RCC) cells in the absence of cytotoxicity. 786-O cells were treated with silibinin at various concentrations, up to 50 µM, for a defined period and then subjected to gelatin zymography, casein zymography, and Western blot to investigate the impacts of silibinin on metalloproteinase (MMP) -2, -9, urokinase plasminogen activator (u-PA), and MAPK pathway signaling proteins, respectively. The results showed that silibinin decreased MMP-2, MMP-9, u-PA, p-p38, and p-Erk1/2 expressions in a concentration-dependent manner. The reduced expressions of MMP-2 and u-PA, as well as inhibition of cell invasion were obtained in the cultures pre-treated with PD98059 (Erk1/2 inhibitor) and SB203580 (p38 inhibitor). An in vivo anti-tumor study with a nude mice xenograft model by a subcutaneous inoculation of 786-O cells demonstrated small solid tumors after eight days following cell inoculation. There was a 70.1% reduction in tumor volume and 69.7% reduction in tumor weight by silibinin feeding on day 44, compared to those of controls. Moreover, combination treatment with silibinin and 5-fluorouracil, paclitaxel, vinblastine, or RAD-001 enhanced the chemosensitivity of 5-fluorouracil and paclitaxel. In conclusion, silibinin inhibits the invasion and migration of 786-O cells in vitro, inhibits the growth of xenografts in vivo, and enhances chemosensitivity to 5-fluorouracil and paclitaxel. © 2011 Wiley-Liss, Inc.

Sequential mTOR inhibitor treatment with temsirolimus in metastatic renal cell carcinoma following failure of VEGF receptor tyrosine kinase inhibitors

PURPOSE

Agents targeting the mammalian target of rapamycin (mTOR) pathway, e. g. everolimus, can provide clinical benefit in pretreated patients with metastatic renal cell carcinoma (mRCC), but data from randomized trials on the sequential use of temsirolimus are lacking. We retrospectively studied the efficacy and safety of temsirolimus therapy following failure of rTKI therapy.

METHODS

Twenty-nine patients treated with temsirolimus (25 mg/week) following progression on rTKI therapy were studied at four institutions. All patients had failed at least one prior rTKI therapy (sunitinib, n = 6; sorafenib, n = 1; both, n = 22). Over 80% had two or more prior therapies. Data on efficacy (response assessment, progression-free survival [PFS], overall survival [OS]) and safety (NCI-CTC) were analyzed.

RESULTS

Adverse events occurred in 90% of patients with the majority being grade 1 (n = 4, 14%) or grade 2 (n = 12, 41%). Most grade 3/4 toxicities (n = 10, 34%) were manageable and included anemia (n = 4, 14%), leukopenia/neutropenia (n = 2, 7%), hyperglycemia (n = 1, 3%), acidosis/alkalosis (n = 2, 7%), and infection (n = 1, 3%). One patient discontinued temsirolimus for grade 3 pneumonitis. Median (range) PFS and OS were 5.1 months (1-10.4) and 18.0 months (12.6-23.3), respectively. Best response included partial response (n = 1) and stable disease (n = 15) for a disease control rate of 55%, and disease progression of 45% (n = 13).

CONCLUSIONS

Temsirolimus after rTKI failure appears to provide promising safety and efficacy comparable to other treatment options in pretreated patients with mRCC.

Prediction of progression-free survival rates after bevacizumab plus interferon versus interferon alone in patients with metastatic renal cell carcinoma: comparison of a nomogram to the Motzer criteria

BACKGROUND

The combination of bevacizumab plus interferon (BEV+IFN) for treatment of metastatic renal cell carcinoma (mRCC) is associated with improved progression-free survival (PFS) in a phase 3 study.

OBJECTIVE

To develop a novel model for prediction of individual PFS using data from the randomized, controlled phase 3 trial of BEV + IFN or interferon alone. The ability of the Motzer criteria for prediction of PFS was also assessed.

DESIGN, SETTING, AND PARTICIPANTS

Pretreatment parameters of 628 patients were included in the Cox regression model predicting PFS at 6, 12, 18, and 24 mo. BEV+IFN was administered to 337 patients; 291 patients received interferon alone. The developed model and the Motzer criteria were internally validated using Harrell's concordance index and calibrated.

RESULTS AND LIMITATIONS

Median PFS was 10.2 versus 4.6 mo (p < 0.001) for patients receiving BEV + IFN or interferon alone, respectively. The novel model relying on age, Karnofsky performance status, baseline albumin, alkaline phosphatase, and time from primary diagnosis to treatment resulted in the highest discrimination (area under the curve [AUC]: 72.8, 75.0, 72.8, and 70.8% at 6, 12, 18, and 24 mo). The AUC of the Motzer criteria risk groups was 63.7, 61.8, 58.6, and 51.8% for the same time points. Comparison of discriminatory ability between the developed model and the Motzer criteria showed statistically significant differences (all p ≤ 0.02). An external validation of the new model is warranted.

CONCLUSIONS

The developed model identified prognostic factors of PFS in mRCC patients treated with BEV+IFN or interferon alone and quantified individual risk of PFS. Relative to the Motzer criteria, the novel model demonstrated better discriminatory properties. The model may serve clinicians in identifying patients who can benefit the most from BEV+IFN versus interferon alone.

Comparative Analysis between Immunochemotherapy and Target Therapy for Metastatic Renal Cell Carcinoma: Overview of Treatment-Related Adverse Events and the Dropout Rate in Korea

Purpose

To comparatively analyze treatment-related adverse events and the treatment dropout rate between immunochemotherapy and target therapy in Korea.

Materials and Methods

Forty-nine subjects with metastatic renal cell carcinoma (21 target therapy recipients and 28 immunochemotherapy recipients) who underwent either 6-week cycles of sunitinib treatment (50 mg once daily for 4 weeks on and 2 weeks off) or 8-week cycles of immunochemotherapy (combination of interleukin [IL]-2, interferon [IFN]-alpha, and 5-fluorouracil [FU]) were enrolled. Treatment-related toxicity was objectively graded and quantitative analysis was performed with a scoring system. Patient compliance was categorized into three classes (1: administration as scheduled, 2: dose modification required, 3: discontinuation required).

Results

Compared with those of the immunochemotherapy group, subjects of the sunitinib-treatment group had higher occurrence rates of mucositis-stomatitis (43% vs. 10%), hand-foot syndrome (38% vs. 0%), diarrhea (33% vs. 14%), and hypertension (33% vs. 14%). According to the toxicity-grade-based scoring system, the total incidence and severity of toxicities were not significantly different between the two groups (p>0.05), whereas high-grade hematologic toxicities were more frequent in the immunochemotherapy group. The dropout rate of the immunochemotherapy group was significantly higher than that of the sunitinib group (administration as scheduled: 52% vs. 21%, p=0.026; discontinuation required: 19% vs. 50%, p=0.037).

Conclusions

The results of this study are indicative of a comparable treatment-related toxicity profile of sunitinib and greater adherence to the treatment protocol in comparison with immunochemotherapy in patients with metastatic renal cell carcinoma (mRCC).