Management of metastatic renal cell carcinoma patients with poor-risk features: current status and future perspectives

Identification of KIF23 as a Prognostic Biomarker Associated With Progression of Clear Cell Renal Cell Carcinoma

About 3% of adult cancers are caused by renal cell carcinoma (RCC) and its pathogenesis remains elusive. Among RCC, clear cell renal cell carcinoma (ccRCC) is the predominant histological subtype. Resistance to conventional treatments leaves few treatment options for advanced ccRCC. Although the transcriptome profile of primary ccRCC has been comprehensively summarized, the transcriptome profile of metastatic ccRCC is still lacking. In this study we identified a list of metastasis-related genes and constructing a metastasis-associated prognostic gene signature. By analyzing data from GSE85258 and GSE105288 datasets, 74 genes were identified as metastasis-related genes. To construct prognostic features, we downloaded the expression data of ccRCC from the Cancer Genome Atlas (TCGA). Metastasis-associated genes were initially selected through the LASSO Cox regression analysis and 12 metastasis-related were included to construct prognostic model. Transcriptome profile, patient prognosis, and immune cell infiltration characteristics differed between low- and high-risk groups after grouping according to median risk score. Through explored the functions of differentially expressed genes (DEGs) between the two groups. Kinesin family member 23 (KIF23) was identified as a prognostic marker in ccRCC patients. Furthermore, inhibition of KIF23 expression reduced the proliferation, migration and invasion of ccRCC cells. We further demonstrated that KIF23 promote nuclear translocation of β-catenin in ccRCC cells, which provides novel insight into the functions and molecular machinery of KIF23 in ccRCC.

Causal Associations between Serum Urea and Cancer: A Mendelian Randomization Study

Urea is largely derived from the urea cycle reactions through hepatic detoxification of free ammonia and cleared by urination, and the serum urea level is a crucial medical indicator for measuring the kidney function in patients with nephropathy; however, investigative revelations pointing to the serum urea level as a risk factor for cancer are very scarce, and relevant studies are restricted by potential biases. We aimed to explore the causal relationships of the serum urea level with cancer development by focusing on renal cell carcinoma (RCC) using the Mendelian randomization (MR) analyses. Summary estimates were collected from the inverse-variance weighted (IVW) method based on six single nucleotide polymorphisms (SNPs). The selected SNPs related to the serum urea were obtained from a large genome-wide association study (GWAS) of 13,312 European participants. The summary statistics of RCC were also available from public databases (IARC, n = 5219 cases, n = 8011 controls). Sensitivity analyses included the weighted median and MR-Egger methods. Serum urea was inversely associated with RCC in females (effect = 1.93; 95% CI: 1.24 to 3.01; p = 0.004) but exhibited null association with RCC in males, breast cancer (BRCA) in both genders and prostate cancer (PCa) in males. Similar conclusions were also drawn from the weighted median and MR-Egger. These findings reveal an intriguing link between serum urea and cancer risks for the very first time. Without ambiguity, the serum urea is causatively related to RCC specifically in females, although the mechanism(s) by which urea is involved in RCC development remains to be experimentally/clinically investigated. Our studies may well provide novel insights for RCC diagnosis, intervention and/or therapy.

Yeast extract inhibits the proliferation of renal cell carcinoma cells via regulation of iron metabolism

The microbiome has recently attracted research interest in a variety of subjects, including cancer. In the present study, it was determined that reinforced clostridium media (RCM) for microbiome culture, exerts antitumor effects on renal cell carcinoma cells when compared to the microbiome 'X'. The antitumor effects of RCM were investigated for all ingredients of RCM, and the results revealed that yeast extract could be a candidate for the ingredient driving this phenomenon. Further experiments including MTT assay, cell counting, cell death analysis, cell cycle analysis and western blotting were conducted with yeast extract on renal cell carcinoma cells (Caki‑1 and Caki‑2) and normal human proximal tubular cells (HK‑2). As a result, yeast extract exhibited dose‑dependent antitumor effects on Caki‑1 and Caki‑2, but only slight effects on HK‑2. In addition, yeast extract only exhibited slight effects on necrosis, autophagy, or apoptosis of Caki‑1 and Caki‑2. Yeast extract produced cell cycle arrest with an increased G0/G1 fraction and a decreased S fraction, and this was considered to be related to the decreased cyclin D1. Although yeast extract treatment increased anti‑oxidant activities, the antitumor effects of yeast extract were also related to iron metabolism, based on the decreased transferrin receptor and increased ferritin. In addition, decreased GPX4 may be related to iron‑dependent cell death, particularly in Caki‑2. These results revealed that yeast extract may inhibit proliferation of renal cell carcinoma cells by regulating iron metabolism. Since an increased iron requirement is a classic phenomenon of cancer cells, yeast extract may be a candidate for adjuvant treatment of renal cell carcinoma.

Association of post-treatment hypoalbuminemia and survival in Chinese patients with metastatic renal cell carcinoma

Background

Hypoalbuminemia adversely affects the clinical outcomes of various cancers. The purpose of this study was to estimate the prognostic value of hypoalbuminemia 3–5 weeks after treatment in patients with metastatic renal cell carcinoma (mRCC) who received sorafenib or sunitinib as first-line treatment.

Methods

In this single-center, retrospective study, we assessed the progression-free survival (PFS) and overall survival (OS) of 184 mRCC patients who received first-line sorafenib or sunitinib treatment. PFS and OS were compared between patients with post-treatment hypoalbuminemia (post-treatment albumin level <36.4 g/L) and those with normal post-treatment albumin level (albumin level ≥36.4 g/L). The Memorial Sloan Kettering Cancer Center (MSKCC) risk model stratified mRCC patients into three risk categories. Prognostic values of all patient characteristics including MSKCC risk category were determined by using univariate and multivariate Cox regression models. Prognostic value was further determined using the Harrell concordance index and receiver operating characteristic curve analysis.

Results

The median PFS and OS of the 184 patients were 11 months (95% confidence interval [CI] 9–12 months) and 23 months (95% CI 19–33 months), respectively. Patients with post-treatment hypoalbuminemia had significantly shorter median PFS (6 months [95% CI 5–7 months]) and OS (11 months [95% CI 9–15 months]) than patients who had normal post-treatment albumin levels (PFS: 12 months [95% CI 11–16 months], P < 0.001; OS: 31 months [95% CI 24–42 months], P < 0.001), respectively. Multivariate analysis showed that post-treatment hypoalbuminemia was an independent predictor of PFS (hazard ratio [HR], 2.113; 95% CI 1.390–3.212; P < 0.001) and OS (HR, 2.388; 95% CI 1.591–3.585; P < 0.001). Post-treatment hypoalbuminemia could also be combined with the MSKCC risk category for better prediction about OS. The model that included post-treatment hypoalbuminemia and MSKCC risk category improved the predictive accuracy for PFS and OS (c-index: 0.68 and 0.73, respectively) compared with the basic MSKCC risk model (c-index: 0.67 and 0.70, respectively). The prognostic values for PFS and OS of the integrated MSKCC risk model involving post-treatment hypoalbuminemia were significantly more accurate than the basic MSKCC risk model using likelihood ratio analysis (both P < 0.001).

Conclusions

Post-treatment hypoalbuminemia can be considered an independent prognostic factor for patients with mRCC who undergo first-line treatment with tyrosine kinase inhibitors. Additionally, integrating post-treatment serum albumin level into the basic MSKCC risk model can improve the accuracy of this model in predicting patient overall survival and progression-free survival.

A case of metastatic renal cell carcinoma showing complete remission after cytoreductive nephrectomy followed by temsirolimus

Here, we present a case report of a patient with poor-risk advanced renal cell carcinoma who had a complete remission after cytoreductive nephrectomy followed by temsirolimus. A 67-year-old woman was diagnosed with advanced renal cell carcinoma, stage pT3aN2M1 in April 2013. In the Memorial Sloan-Kettering Cancer Center criteria, she had three prognostic factors and was classified into the poor-risk category. After 23 weeks of treatment with temsirolimus, complete remission was achieved. Temsirolimus treatment was discontinued after 23 weeks because of grade 3 toxicity noninfectious pneumonitis. Five months after beginning steroid treatment without temsirolimus, a CT scan showed no new metastatic lesion or progression of disease. This was a very rare case with achievement of a complete remission after cytoreductive nephrectomy followed by temsirolimus.

The value of hepatic resection in metastasic renal cancer in the Era of Tyrosinkinase Inhibitor Therapy

BACKGROUND

The value of liver-directed therapy (LDT) in patients with metastasic renal cell carcinoma (MRCC) is still an active field of research, particularly in the era of tyrosinkinase inhibitor (TKI) therapy.

METHODS

The records of 35 patients with MRCC undergoing LDT of metastasic liver lesions between 1992 and 2015 were retrospectively analyzed. Immediate postoperative TKI was given in a subgroup of patients after LDT for metastasic lesions. Uni- and multivariate models were applied to assess overall survival (OS), progression-free survival (PFS) and disease-free survival (DFS).

RESULTS

Following primary tumor (renal cell cancer) resection and LDT, respectively, median OS was better for a total of 16 patients (41 %) receiving immediate postoperative TKI with 151 and 98 months, when compared to patients without TKI therapy with 61 (p = 0.003) and 40 months (p = 0.032). Immediate postoperative TKI was associated with better median PFS (47 months versus 19 months; p = 0.023), whereas in DFS only a trend was observed (51 months versus 19 months; p = 0.110).

CONCLUSIONS

LDT should be considered as a suitable additive tool in the era of TKI therapy of MRCC to the liver. In this context, postoperative TKI therapy seems to be associated with better OS and PFS, but not DFS.

Chrysophanic Acid Induces Necrosis but not Necroptosis in Human Renal Cell Carcinoma Caki-2 Cells

Background:

Chrysophanic acid, also known as chrysophanol, has a number of biological activities. It enhances memory and learning abilities, raises superoxide dismutase activity, and has anti-cancer effects in several model systems. According to previous reports, chrysophanic acid-induced cell death shares features of necrotic cell death. However, the molecular and cellular processes underlying chrysophanic acid-induced cell death remain poorly understood.

Methods:

Chrysophanic acid-induced cell death was monitored by cell viability assay and Annexin V-propidium iodide (PI) staining of renal cell carcinoma Caki-2 cells. The induction of intracellular reactive oxygen species (ROS) by chrysophanic acid and the suppression of ROS by anti-oxidants were evaluated by 2′,7′-dichlorofluorescin diacetate staining. The expression and phosphorylation of proteins that are involved in apoptosis and necroptosis were detected by immunoblotting.

Results:

The extent of chrysophanic acid-induced cell death was concentration and time dependent, and dead cells mainly appeared in the PI-positive population, which is a major feature of necrosis, upon fluorescence-activated cell sorting analysis. Chrysophanic acid-induced cell death was associated with the generation of intracellular ROS, and this effect was reversed by pretreatment with N-acetyl cysteine. Chrysophanic acid-induced cell death was not associated with changes in apoptotic or necroptotic marker proteins.

Conclusions:

The cell death induced by chrysophanic acid resembled neither apoptotic nor necroptotic cell death in human renal cell carcinoma Caki-2 cells.

Mediastinal lymph node metastasis of renal cell carcinoma: A case report

Renal cell carcinoma (RCC) may metastasize to mediastinal lymph nodes without any abdominal lymph node involvement. The present study describes an autopsy-proven case of RCC presenting with a large mediastinal mass; the case had been previously misdiagnosed as small cell lung carcinoma due to imaging analysis results, an elevated serum level of neuron-specific enolase and the presence of small atypical cells with a high nuclear/cytoplasmic ratio. Despite RCC occurrence being rare, it should be considered in the differential diagnosis, particularly when a mass located in the kidneys presents with metastases to the mediastinal lymph nodes, even if there is no involvement of the abdominal lymph nodes and the primary lesion is of a small size.

Assessing the impact of evolving evidence in renal cell carcinoma treatment: an update of the Renal Cell Carcinoma Appropriateness-based Treatment Toolkit (ReCATT)

The appropriateness of the numerous therapeutic options available for patients with advanced or metastatic renal cell carcinoma (RCC) was evaluated in 2011, using the RAND/University of California, Los Angeles (UCLA) appropriateness methodology to match treatment suitability to a range of patient scenarios. However, the RCC therapeutic area evolves rapidly and a body of new clinical data has accrued in the intervening years; as a result the exercise was repeated in 2013 using the same methodology, expert panel and patient scenarios. The aim of the updated assessment was to update the guidance to clinicians and use it to develop an interactive web-based application, the Renal Cell Carcinoma Appropriateness-based Treatment Toolkit (ReCATT). This round of assessment achieved greater concordance concerning the appropriateness of treatments/interventions for the clinical scenarios tested; this higher level of agreement is likely to reflect the body of scientific evidence accrued since the previous assessment exercise. Many of the areas of disagreement in 2011 related to the suitability of pazopanib or sunitinib treatment; in the 2013 assessment both agents were considered appropriate treatment options for many of the clinical scenarios assessed. Uncertain scenarios often are related to the optimal management of metastatic RCC with clear cell histology. The use of the RAND/UCLA RCC assessment findings to develop the ReCATT support tool will help to disseminate expert opinion concerning best treatment practice and guide the clinical management of RCC patients treated in the community setting.

DACH1 inhibits cyclin D1 expression, cellular proliferation and tumor growth of renal cancer cells

Background

Renal cell carcinoma (RCC) is a complex with diverse biological characteristics and distinct molecular signature. New target therapies to molecules that drive RCC initiation and progression have achieved promising responses in some patients, but the total effective rate is still far from satisfaction. Dachshund (DACH1) network is a key signaling pathway for kidney development and has recently been identified as a tumor suppressor in several cancer types. However, its role in renal cell carcinoma has not been fully investigated.

Methods

Immunohistochemical staining for DACH1, PCNA and cyclin D1 was performed on human renal tissue microaraays and correlation with clinic-pathological characteristics was analyzed. In vitro proliferation, apoptosis and in vivo tumor growth were evaluated on human renal cancer cell lines with decitabine treatment or ectopic expression of DACH1. Downstream targets and potential molecular mechanism were investigated through western blot, immunoprecipitation and reporter gene assays.

Results

Expression of DACH1 was significantly decreased in human renal carcinoma tissue. DACH1 protein abundance was inversely correlated with the expression of PCNA and cyclin D1, tumor grade, and TNM stage. Restoration of DACH1 function in renal clear cell cancer cells inhibited in vitro cellular proliferation, S phase progression, clone formation, and in vivo tumor growth. In mechanism, DACH1 repressed cyclin D1 transcription through association with AP-1 protein.

Conclusion

Our results indicated that DACH1 was a novel molecular marker of RCC and it attributed to the malignant behavior of renal cancer cells. Re-activation of DACH1 may represent a potential therapeutic strategy.