Immunologics and chemotherapeutics for renal cell carcinoma

Corosolic acid inhibits metastatic response of human renal cell carcinoma cells by modulating ERK/MMP2 signaling

Corosolic acid (CA), a plant-derived pentacyclic triterpenoid, has potent anti-inflammatory, anti-metabolic, and anti-neoplastic actions against a variety of human cancers. However, the specific mechanism by which CA inhibits the progression of renal cell carcinoma (RCC) is yet unclear. We found that CA (≤8 μM) had no influence on either the growth or viability of RCC cell lines (786-O, ACHN, and Caki-1) or normal HK2 cells. However, in a dose-dependent manner, CA prevented the invasion and migration of RCC cells. Human protease array analysis showed that CA reduced MMP2 expression. At increasing concentrations of CA, the expression of MMP2 was dose-dependently reduced, as shown by western blot and RT-PCR analyses as well as immunofluorescence staining. CA also stimulated ERK1/2 phosphorylation in 786-O and Caki-1 cells. Transfection of CA-treated RCC cells with siRNA-ERK restored MMP2 protein expression and the motility and invasion capabilities of RCC cells. Molecular docking study results showed that CA and MMP2 interact strongly. These findings elucidate the mechanism by which CA prevents RCC cells from migrating and invading, and these findings indicate that CA may be a potential anti-metastatic therapy for RCC.

Prognostic value of preoperative NLR, dNLR, PLR and CRP in surgical renal cell carcinoma patients

BACKGROUND

Emerging evidences indicate that inflammation plays a crucial role in carcinogenesis and tumor progression. Inflammatory response biomarkers are recognized as promising prognostic factors for improving predictive accuracy in renal cell carcinoma (RCC). We aimed to evaluate the prognostic significance of preoperative neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), platelet-to-lymphocyte ratio (PLR) and serum C-reactive protein (CRP) in RCC.

METHODS

484 surgical RCC patients were enrolled from 2006 to 2010 in this study. Receiver operating curve (ROC) was applied to assess the optimal cutoff levels for four biomarkers, and the prognostic values were determined by Kaplan-Meier curve, univariate and multivariate COX regression models. The predictive accuracy was evaluated by concordance index (c-index).

RESULTS

The median follow-up duration after surgical resection was 36 months. The optimal cutoff levels were 2.78 for NLR, 2.05 for dNLR, 185 for PLR and 5.1 for CRP by ROC curves analysis. Elevated NLR, dNLR, PLR and CRP were significantly correlated with worse overall survival (OS). Multivariate analysis showed that elevated NLR was an independent risk factor for OS, and NLR was superior to dNLR, PLR and CRP based on hazard ratio (HR 2.10, 95 % CI 1.21-3.64, P = 0.008). Additionally, the nomogram could more effectively work in predicting OS (c-index: 0.749) in surgical RCC patients.

CONCLUSION

Pre-operation NLR can be considered as a potential prognostic biomarker in patients with RCC who underwent surgical resection.

Effect of actionable somatic mutations on racial/ethnic disparities in head and neck cancer prognosis

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and minorities have the worst survival. However, the molecular mechanisms underlying survival disparities have not been elucidated.

METHODS

In a retrospective study, we assessed association between HNSCC early death (<2 years) and 208 somatic mutations of 10 cancer-related genes in 214 patients: 98 non-Hispanic whites (46%), 72 Hispanic whites (34%), and 44 African Americans (20%).

RESULTS

Hispanic whites and African Americans had significantly higher mutation rates for EGFR, HRAS, KRAS, and TP53. HNSCC early death was significantly associated with 3+ mutations (odds ratio [OR] = 2.78, 95% confidence interval [CI] = 1.16, 6.69), NOTCH1 mutations in non-Hispanic whites (OR = 5.51; 95% CI = 1.22-24.83) and TP53 mutations in Hispanic whites (OR = 3.84; 95% CI = 1.08-13.68) in multivariable analysis adjusted for age, sex, tumor site, and tumor stage.

CONCLUSION

We have provided the proof-of-principal data to link racial/ethnic-specific somatic mutations and HNSCC prognosis and pave the way for precision medicine to overcome HNSCC survival disparities. © 2016 Wiley Periodicals, Inc. Head Neck 38:1234-1241, 2016.

Demethylation drug 5-Aza-2'-deoxycytidine-induced upregulation of miR-200c inhibits the migration, invasion and epithelial-mesenchymal transition of clear cell renal cell carcinoma in vitro

The microRNA (miR)-200 family has been found to be involved in the process of mesenchymal-epithelial transition during renal development. Deregulation of miR-200c has been suggested to be involved in clear cell renal cell carcinoma (ccRCC). However, the precise role of miR-200c in the regulation of ccRCC metastasis has not been previously reported. In the present study, it was observed that miR-200c was frequently downregulated in ccRCC tissue compared with matched adjacent normal tissue. The expression of miR-200c was additionally reduced in ccRCC cell lines when compared with levels in normal renal cells. The DNA demethylation drug 5-Aza-2'-deoxycytidine (Aza) was used to treat several ccRCC cell lines, and it was observed that the expression of miR-200c was significantly increased following Aza treatment. Furthermore, treatment with Aza markedly inhibited ccRCC cell invasion and migration, while treatment with miR-200c inhibitor significantly enhanced invasion and migration of ccRCC cells. In addition, Aza treatment significantly promoted expression of E-cadherin and inhibited the expression of N-cadherin, while the inhibition of miR-200c downregulated E-cadherin and upregulated the expression of N-cadherin, suggesting that miR-200c has a suppressive role in epithelial-mesenchymal transition (EMT) of ccRCC cells. In conclusion, it was suggested that demethylation drug Aza-induced upregulation of miR-200c may inhibit migration, invasion and EMT in ccRCC cells.

Thyroid Hormones as Renal Cell Cancer Regulators

It is known that thyroid hormone is an important regulator of cancer development and metastasis. What is more, changes across the genome, as well as alternative splicing, may affect the activity of the thyroid hormone receptors. Mechanism of action of the thyroid hormone is different in every cancer; therefore in this review thyroid hormone and its receptor are presented as a regulator of renal cell carcinoma.

Bevacizumab: a review of its use in advanced cancer

The humanized monoclonal antibody bevacizumab (Avastin(®)) has been available in the EU since 2005. Results of phase III trials demonstrate that adding intravenous bevacizumab to antineoplastic agents improves progression-free survival and/or overall survival in patients with advanced cancer, including when used as first- or second-line therapy in metastatic colorectal cancer, as first-line therapy in advanced nonsquamous non-small cell lung cancer, as first-line therapy in metastatic renal cell carcinoma, as first-line therapy in metastatic breast cancer, and as first-line therapy in epithelial ovarian, fallopian tube or primary peritoneal cancer or in recurrent, platinum-sensitive or platinum-resistant disease. Results of these studies are supported by the findings of routine oncology practice studies conducted in real-world settings. The tolerability profile of bevacizumab is well defined and adverse events associated with its use (e.g. hypertension, proteinuria, haemorrhage, wound healing complications, arterial thromboembolism, gastrointestinal perforation) are generally manageable. In conclusion, bevacizumab remains an important option for use in patients with advanced cancer.

Prognostic role of the neutrophil-lymphocyte ratio in renal cell carcinoma: a meta-analysis

OBJECTIVE

Increasing evidence suggests that cancer-associated inflammation is associated with poor prognosis in patients with cancer. The role of the neutrophil-lymphocyte ratio (NLR) as a predictor in renal cell carcinoma (RCC) remains controversial. We conducted the meta-analysis to determine the association between NLR and clinical outcome of patients with RCC.

METHODS AND MATERIALS

Studies were identified from PubMed and EMBASE databases in March 2014. Meta-analysis was performed to generate combined HRs with 95% CIs for overall survival (OS) and recurrence-free/progress-free survival (RFS/PFS).

RESULTS

15 cohorts containing 3357 patients were included. Our analysis results indicated that elevated NLR predicted poorer OS (HR=1.82, 95% CI 1.51 to 2.19) and RFS/PFS (HR=2.18, 95% CI 1.75 to 2.71) in patients with RCC. These findings were robust when stratified by study region, sample size, therapeutic intervention, types of RCC and study quality. However, it differed significantly by assessment of the cut-off value defining 'elevated NLR' in RFS/PFS (p=0.004). The heterogeneity in our meta-analysis was mild to moderate.

CONCLUSIONS

Elevated NLR indicates a poorer prognosis for patients with RCC. NLR should be monitored in patients with RCC for rational risk stratification and treatment individualisation.

SOX9 was involved in TKIs resistance in renal cell carcinoma via Raf/MEK/ERK signaling pathway

Renal cell carcinoma (RCC) is common genitourinary malignancy in human, 30-40% of patients with RCC would be diagnosed with metastatic RCC (mRCC). Even in the era of targeted therapy, patients with mRCC would inevitably progress due to drug resistance. Herein, exploration of the mechanisms of resistance is noteworthy to study. In the present study, we firstly reported the expression profile of SOX9 in renal carcinoma cells and tissues, and found that its expression was significantly associated with Fuhrman grading. Dual luciferase analysis confirmed that Raf/MEK/ERK pathway could directly be regulated by SOX9, and sequential experiments demonstrated that, renal carcinoma cells could sensitize to Sorafenib/Sunitinib through Raf/MEK/ERK signaling pathway inhibition regulated by SOX9 down-regulation. In a small cases with mRCC treated with Sorafenib/Sunitinib (n=38), comparative analysis showed that patients with SOX9 (-) had much better therapeutic response to TKIs than those with SOX9 (+) (PD: 9.1% vs. 56.2%, P=0.002, DCR: 90.9% vs. 43.8%, P=0.002). Based on these findings, we concluded that, SOX9 was firstly described to be highly expressed in renal cell carcinoma, and its expression was involved in TKIs drug resistance through activation of Raf/MEK/ERK pathway. In vitro, patients with SOX9 (-) was related to better response to TKIs treatment than those with SOX9 (+). SOX9 could be expected to be a promising biomarker predicting TKIs response and even expected to be another novel target in the treatment of mRCC.

Upregulation of microRNA-492 induced by epigenetic drug treatment inhibits the malignant phenotype of clear cell renal cell carcinoma in vitro

Clear cell renal cell carcinoma (ccRCC) is the most common type of cancer of the renal parenchyma. MicroRNAs (miRNAs) are non-coding RNAs of ~22 nucleotides in length, which function as post‑transcriptional regulators. Recently, the downregulation of miRNA (miR)-492 was observed to be associated with ccRCC; however, the molecular mechanism by which miR492 inhibited ccRCC remained to be elucidated. In the present study, it was demonstrated that miR-492 was markedly downregulated in ccRCC tissues when compared with adjacent normal tissues, as determined by reverse transcription-quantitative poymerase chain reaction (PCR). This downregulation was predominantly due to the hypermethylation of the CpG island of the miR-492 promoter, which was detected by methylation specific PCR and bisulfite genomic sequencing PCR, and was shown to inhibit miR-492 transcription. Through the use of a DNA demethylation agent, 5-aza-2'-deoxycytidine or the histone deacetylase inhibitor 4-phenylbutyric acid, the expression level of miR-492 was significantly upregulated in ccRCC cells, which further inhibited cell proliferation and invasion, while promoting cell apoptosis and adhesion. In conclusion, the present study provided novel insights into the potential mechanisms involved in ccRCC and it is hypothesized that miR-492 may become a promising therapeutic agent in the treatment of ccRCC.

Biology of renal tumour cancer stem cells applied in medicine

The present article highlights the diverse role of stem cells in normal kidney and renal cancer, with special emphasis on surface markers. Proteins such as CD105 and CD133 have been reported as being significant in clear cell renal cell carcinoma (ccRCC) cancer stem cells. The role of normal kidney progenitor cells and their surface markers is compared with the role of those surface markers in ccRCC. Subsequently, we state the current hypothesis about origin of tumour-initiating cells along with their clinical and prognostic potential in RCC. Finally, we present future perspectives with respect to recent studies.