Novel potential predictive markers of sunitinib outcomes in long-term responders versus primary refractory patients with metastatic clear-cell renal cell carcinoma

Identification of miRNAs and Their Target Genes Associated with Sunitinib Resistance in Clear Cell Renal Cell Carcinoma Patients

Sunitinib has greatly improved the survival of clear cell renal cell carcinoma (ccRCC) patients in recent years. However, 20-30% of treated patients do not respond. To identify miRNAs and genes associated with a response, comparisons were made between biopsies from responder and non-responder ccRCC patients. Using integrated transcriptomic analyses, we identified 37 miRNAs and 60 respective target genes, which were significantly associated with the NF-kappa B, PI3K-Akt and MAPK pathways. We validated expression of the miRNAs (miR-223, miR-155, miR-200b, miR-130b) and target genes (FLT1, PRDM1 and SAV1) in 35 ccRCC patients. High levels of miR-223 and low levels of FLT1, SAV1 and PRDM1 were associated with worse overall survival (OS), and combined miR-223 + SAV1 levels distinguished responders from non-responders (AUC = 0.92). Using immunohistochemical staining of 170 ccRCC patients, VEGFR1 (FLT1) expression was associated with treatment response, histological grade and RECIST (Response Evaluation Criteria in Solid Tumors) score, whereas SAV1 and BLIMP1 (PRDM1) were associated with metachronous metastatic disease. Using in situ hybridisation (ISH) to detect miR-155 we observed higher tumoural cell expression in non-responders, and non-tumoural cell expression with increased histological grade. In summary, our preliminary analysis using integrated miRNA-target gene analyses identified several novel biomarkers in ccRCC patients that surely warrant further investigation.

External validation of a red cell-based blood prognostic score in patients with metastatic renal cell carcinoma treated with first-line immunotherapy combinations

Immunotherapy combinations with tyrosine-kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) had significantly improved outcomes of patients with mRCC. Predictive and prognostic factors are crucial to improve patients' counseling and management. The present study aimed to externally validate the prognostic value of a previously developed red cell-based score, including hemoglobin (Hb), mean corpuscular volume (MCV) and red cell distribution width (RDW), in patients with mRCC treated with first-line immunotherapy combinations (TKI plus ICI or ICI plus ICI). We performed a sub-analysis of a multicentre retrospective observational study (ARON-1 project) involving patients with mRCC treated with first-line immunotherapy combinations. Uni- and multivariable Cox regression models were used to assess the correlation between the red cell-based score and progression-free survival (PFS), and overall survival (OS). Logistic regression were used to estimate the correlation between the score and the objective response rate (ORR). The prognostic impact of the red cell-based score on PFS and OS was confirmed in the whole population regardless of the immunotherapy combination used [median PFS (mPFS): 17.4 vs 8.2 months, HR 0.66, 95% CI 0.47-0.94; median OS (mOS): 42.0 vs 17.3 months, HR 0.60, 95% CI 0.39-0.92; p < 0.001 for both]. We validated the prognostic significance of the red cell-based score in patients with mRCC treated with first-line immunotherapy combinations. The score is easy to use in daily clinical practice and it might improve patient counselling.

Long-term Clinical Outcomes of a Spanish Cohort of Metastatic Renal Cell Carcinoma Patients with a Complete Response to Sunitinib

INTRODUCTION

The long-term clinical outcomes of patients with metastatic renal cell carcinoma (mRCC) and a complete response (CR) to the tyrosine kinase inhibitor (TKI) sunitinib are poorly known. The characteristics of these patients could reveal previously undetected associations with clinical variables.

PATIENTS AND METHODS

This observational, retrospective study (ATILA) used data from a registry of patients with mRCC who had received first-line sunitinib and had achieved CR from 2007 to 2018 in Spain.

RESULTS

Sixty-two patients with CR were included; 48 patients (77.4%) received sunitinib in monotherapy and 14 (22.6%) combined with or followed by local treatment. Median age was 58.5 years (range, 32-81). Most patients (79.0%) had clear cell histology and had undergone previous nephrectomy (90.3%). The majority (70.2%) had an intermediate IMDC prognosis, 23% favorable and 7.0% poor. The median time on treatment with sunitinib was 28.2 months (IQR, 16.7-41.0) and the median time to CR was 10.9 months (IQR, 7.2-19.3). After a median follow-up of 8 years (range, 3-13 years), the median PFS was not reached. The overall median duration of complete response was 64.1 months (IQR, 32.2-99.4). The tolerance and safety profile of sunitinib was consistent with previous reports.

CONCLUSION

Durable CR to sunitinib was observed in patients regardless the prognosis group, metastasis site or histology type, with 75% of patients remaining in CR after 10 years.

CLINICALTRIALS

gov: NCT03916458.

Clinical Factors Associated With Long-Term Benefit in Patients With Metastatic Renal Cell Carcinoma Treated With Axitinib: Real-World AXILONG Study

BACKGROUND

Axitinib monotherapy obtained approval in pre-treated mRCC patients and recently in combination with pembrolizumab or avelumab in the first-line setting. However, patient profiles that may obtain increased benefit from this drug and its combinations still need to be identified.

PATIENTS AND METHODS

Retrospective multicentre analysis describing clinical characteristics associated with axitinib long-responder (LR) population by comparing two extreme-response sub-groups (progression-free survival [PFS] ≥9 months vs. disease progression/refractory patients [RP]). A multivariate logistic-regression model was used to analyse clinical factors. Efficacy and safety were also analysed.

RESULTS

In total, 157 patients who received axitinib in second or subsequent line were evaluated (91 LR and 66 RP). Older age at start of axitinib and haemoglobin levels > LLN were independent predictive factors for LR in multivariate analyses. In LR patients, median (m) PFS was 18.1 months, median overall survival was 36.0 months and objective response rate (ORR) was 45.5%. In 59 LR patients receiving axitinib in second-line, mPFS was 18.7 months, mOS was 44.8 months and ORR was 43.9%. mOS was significantly longer in second line compared to subsequent lines (44.8 vs. 26.5 months; P = .009). In LR vs. RP, mPFS with sunitinib in first-line was correlated with mPFS with axitinib in second-line (27.2 vs. 10.9 months P < .001). The safety profile was manageable and consistent with known data.

CONCLUSIONS

This study confirms the long-term benefits of axitinib in a selected population, helping clinicians to select the best sequential approach and patients who could obtain a greater benefit from axitinib.

Methylation and expression levels of microRNA-23b/-24-1/-27b, microRNA-30c-1/-30e, microRNA-301a and let-7g are dysregulated in clear cell renal cell carcinoma

BACKGROUND

Renal cell carcinoma is the most common form of kidney cancer in adults. DNA methylation of regulatory sequences at the genomic level and interaction between microRNAs and the messenger RNAs of target genes at the posttranscriptional level contribute to the dynamic regulation of gene activity. Aberrations in these mechanisms can result in impaired functioning of cell signaling pathways, such as that observed in malignant tumors. We hypothesized that microRNA genes methylation may be associated with renal cancer in patients.

METHODS AND RESULTS

We examined methylation levels of 22 microRNA genes in tumor and normal kidney tissue of 30 patients with TNM Stage III clear cell renal cell carcinoma using a pathway-specific real-time polymerase chain reaction array (EpiTect Methyl II PCR Arrays, Qiagen). MicroRNA expression analysis by quantitative polymerase chain reaction was also performed. Significant differences in methylation levels were found in two genes and in two clusters of microRNA genes. MicroRNA-23b/-24-1/-27b, microRNA -30c-1/-30e and let-7 g was hypermetylated in clear cell renal cell carcinoma tissue, microRNA -301a was hypomethylated in tumor compared with the adjacent normal tissues. Expression of microRNA-301a, microRNA-23b in the clear cell renal cell carcinoma tissues was significantly overexpressed when compared with the adjacent normal tissues and let-7 g was significantly downregulated in tumor.

CONCLUSIONS

Our results may indicate the contribution of microRNA-301a, microRNA-23b and let-7 g in the pathogenesis of renal cancer, but further studies are needed to determine the functional significance of the detected changes.

Epigenetic Alterations in Renal Cell Cancer With TKIs Resistance: From Mechanisms to Clinical Applications

The appearance of tyrosine kinase inhibitors (TKIs) has been a major breakthrough in renal cell carcinoma (RCC) therapy. Unfortunately, a portion of patients with TKIs resistance experience disease progression after TKIs therapy. Epigenetic alterations play an important role in the development of TKIs resistance. Current evidence suggests that epigenetic alterations occur frequently in RCC patients with poor response to TKIs therapy, and modulation of them could enhance the cytotoxic effect of antitumor therapy. In this review, we summarize the currently known epigenetic alterations relating to TKIs resistance in RCC, focusing on DNA methylation, non-coding RNAs (ncRNAs), histone modifications, and their interactions with TKIs treatment. In addition, we discuss application of epigenetic alteration analyses in the clinical setting to predict prognosis of patients with TKIs treatment, and the potential use of epigenetics-based therapies to surmount TKIs resistance.

MicroRNA Signature in Renal Cell Carcinoma

Renal cell carcinoma (RCC) includes 2.2% of all diagnosed cancers and 1.8% of cancer-related mortalities. The available biomarkers or screening methods for RCC suffer from lack of sensitivity or high cost, necessitating identification of novel biomarkers that facilitate early diagnosis of this cancer especially in the susceptible individuals. MicroRNAs (miRNAs) have several advantageous properties that potentiate them as biomarkers for cancer detection. Expression profile of miRNAs has been assessed in biological samples from RCC patients. Circulatory or urinary levels of certain miRNAs have been proposed as markers for RCC diagnosis or follow-up. Moreover, expression profile of some miRNAs has been correlated with response to chemotherapy, immunotherapy or targeted therapeutic options such as sunitinib. In the current study, we summarize the results of studies that assessed the application of miRNAs as biomarkers, therapeutic targets or modulators of response to treatment modalities in RCC patients.

Renal Cell Tumors: Uncovering the Biomarker Potential of ncRNAs

Renal cell tumors (RCT) remain as one of the most common and lethal urological tumors worldwide. Discrimination between (1) benign and malignant disease, (2) indolent and aggressive tumors, and (3) patient responsiveness to a specific therapy is of major clinical importance, allowing for a more efficient patient management. Nonetheless, currently available tools provide limited information and novel strategies are needed. Over the years, a putative role of non-coding RNAs (ncRNAs) as disease biomarkers has gained relevance and is now one of the most prolific fields in biological sciences. Herein, we extensively sought the most significant reports on ncRNAs as potential RCTs' diagnostic, prognostic, predictive, and monitoring biomarkers. We could conclude that ncRNAs, either alone or in combination with currently used clinical and pathological parameters, might represent key elements to improve patient management, potentiating the implementation of precision medicine. Nevertheless, most ncRNA biomarkers require large-scale validation studies, prior to clinical implementation.

MicroRNA-628-5p inhibits invasion and migration of human pancreatic ductal adenocarcinoma via suppression of the AKT/NF-kappa B pathway

The biological function and underlying mechanism of microRNA-628-5p (miR-628-5p) remains to be clarified in the growth and progression of pancreatic ductal adenocarcinoma (PDAC). Here, the expression levels of miR-628-5p in PDAC tissues and cells were detected by quantitative reverse transcriptase polymerase chain reaction and in situ hybridization. The relationship between miR-628-5p expression and clinicopathologic characteristics was examined in human PDAC tissue samples. Gain- and loss-of-function and the putative targets of miR-628-5p were evaluated in PDAC cell lines. The upstream and downstream signals of miR-628-5p in PDAC were also examined. MiR-628-5p was lowly expressed in PDAC tissues and cell lines, and low miR-628-5p expression in PDAC tissues was associated with poor clinicopathological characteristics and shorter overall survival. Functionally, restoration of miR-628-5p expression decreased PDAC cell proliferation, migration, invasion, and promoted cell apoptosis, whereas miR-628-5p silencing abolished these biological behaviors. MiR-628-5p was found to target and negatively regulate phospholipid scramblase 1 and insulin receptor substrate 1 expression, which resulted in the inhibition of the AKT/NF-κB signaling pathway. MYC knockdown led to miR-628-5p upregulation, whereas MYC overexpression repressed miR-628-5p expression. These findings indicate that miR-628-5p functions as a tumor-suppressive microRNA in PDAC and implicate miR-628-5p as a potential therapeutic target for PDAC patients.

Emerging role of microRNA 628-5p as a novel biomarker for cancer and other diseases

MicroRNAs are a family of small, single-stranded RNAs that have key roles in regulating multiple signaling pathways within a cell. Studies have implicated aberrant expression of microRNAs in the development and progression of several pathologies including cancer. MicroRNAs are relatively stable and readily available in body fluids and tissues, making them desirable biomarkers for prognostic and diagnostic purposes in an array of diseases. MicroRNA 628 (5p/3p variants) is located in the 15q21.3 cancer-related region, and evidence suggests its association with various pathologies. The -5p mature variant, microRNA 628-5p, has been reported to be differentially expressed in various cancers, and its expression has been mostly associated with tumor suppression but there are few reports identifying its role in cancer progression. Several studies have also suggested its utility in diagnosis and prognosis of various cancers. Dysregulation of microRNA 628-5p has also been implicated in embryonal implantation defects, autism, immune modulation, myogenesis, cardiovascular disease, viral infection, and skeletal muscle repair. Here, we have provided a comprehensive review on available literature explaining the role of microRNA 628-5p as a potential cancer biomarker as well as briefly describe its function in other diseases and normal physiological conditions.

Molecular Mechanisms in Clear Cell Renal Cell Carcinoma: Role of miRNAs and Hypermethylated miRNA Genes in Crucial Oncogenic Pathways and Processes

Clear cell renal cell carcinoma (ccRCC) is the third most common urological cancer, and it has the highest mortality rate. The increasing drug resistance of metastatic ccRCC has resulted in the search for new biomarkers. Epigenetic regulatory mechanisms, such as genome-wide DNA methylation and inhibition of protein translation by interaction of microRNA (miRNA) with its target messenger RNA (mRNA), are deeply involved in the pathogenesis of human cancers, including ccRCC, and may be used in its diagnosis and prognosis. Here, we review oncogenic and oncosuppressive miRNAs, their putative target genes, and the crucial pathways they are involved in. The contradictory behavior of a number of miRNAs, such as suppressive and anti-metastatic miRNAs with oncogenic potential (for example, miR-99a, miR-106a, miR-125b, miR-144, miR-203, miR-378), is examined. miRNAs that contribute mostly to important pathways and processes in ccRCC, for instance, PI3K/AKT/mTOR, Wnt-β, histone modification, and chromatin remodeling, are discussed in detail. We also separately consider their participation in crucial oncogenic processes, such as hypoxia and angiogenesis, metastasis, and epithelial-mesenchymal transition (EMT). The review also considers the interactions of long non-coding RNAs (lncRNAs) and miRNAs of significance in ccRCC. Recent advances in the understanding of the role of hypermethylated miRNA genes in ccRCC and their usefulness as biomarkers are reviewed based on our own data and those available in the literature. Finally, new data and perspectives concerning the clinical applications of miRNAs in the diagnosis, prognosis, and treatment of ccRCC are discussed.

MicroRNA 628 suppresses migration and invasion of breast cancer stem cells through targeting SOS1

Purpose

The purpose of this study is to evaluate the effects of miR-628 on migration and invasion of breast cancer stem cells (CSCs), which are essential for tumor recurrence and metastasis.

Materials and methods

Quantitative reverse transcription-polymerase chain reaction was used to determine the expression of microRNAs and mRNAs. A subpopulation of CD44⁺/CD24⁻ breast CSCs were sorted by flow cytometry. Transwell assays were used to evaluate cell migration and invasion. Luciferase reporter assays were performed to verify whether miR-628 targeted SOS Ras/Rac guanine nucleotide exchange factor 1 (SOS1). pcDNA3.1(+)-SOS1 was constructed for overexpressing SOS1 after transfection.

Results

Compared with primary breast cancer cells, bone metastatic breast cancer cells showed significant downregulation of miR-628. The CD44⁺/CD24⁻ breast CSC subpopulations in MDA-MB-231 and MCF-7 cell lines were analyzed and sorted. Transfection with an miR-628 mimic significantly suppressed the migration and invasion of these breast CSCs by targeting SOS1, which plays an essential role in epithelial-to-mesenchymal transition. Overexpression of SOS1 rescued miR-628-mediated migration and invasion by upregulating Snail and vimentin, and downregulating E-cadherin.

Conclusion

miR-628 suppressed migration and invasion of breast CSCs of MDA-MB-231 and MCF-7 cells by directly targeting SOS1. Enhancement of miR-628 expression might be an effective strategy for managing breast cancer metastasis.

MicroRNAs as biomarkers in chronic kidney disease

PURPOSE OF REVIEW

This review summarizes recent data supporting the concept that urinary microRNAs are a useful new class of biomarker. They may improve capacity to stratify patients with chronic kidney disease according to risk of progression, and may also inform about response to therapy.

RECENT FINDINGS

MicroRNAs are present, stable and readily quantifiable in tissues and body fluids, including urine, and have widespread importance as regulators in the kidney. Urinary microRNAs are typically released from the nephron or downstream structures, and their abundance may reflect altered microRNA expression in the kidney, or release into the lumen by the cells comprising the different regions of the nephron. As a consequence, abundance of specific microRNAs in the urine may change in various pathological states. Large-scale studies are now needed, to test the capacity of specific microRNAs to inform about risk and response to therapy.

SUMMARY

Urinary microRNAs appear useful sentinels for pathological processes occurring in the kidney and may enable a 'personalized medicine' approach to the management and stratification of renal disease.

Diagnostic and prognostic value of microRNA-628 for cancers

Background: Many studies manifested miRNA-628 (miR-628) was deregulated in various cancers, indicating that miR-628 might serve as a novel biomarker of cancer diagnosis and prognosis, but it's role was still uncertain. This study aimed to evaluate the value of miR-628 in various cancers for diagnosis and prognosis, as well as its predictive power in combination biomarkers.

Materials and Methods: A literature search was performed using Medline (via PubMed), Embase, Web of Science databases, and Ovid platform up to November 2017. Meta-analysis was performed to provide summative outcomes. Quality assessment of each included study was performed.

Results: Twelve articles with 20 studies were included in our meta-analysis, including 8 articles with 15 studies for diagnostic meta-analysis and 4 articles with 5 studies for prognostic meta-analysis. For the diagnostic meta-analysis of miR-628 alone, the overall pooled results for sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the area under the summary receiver operating characteristic (SROC) curve (AUC) were 0.81 (95% CI: 0.62-0.91), 0.72 (95% CI: 0.48-0.88), 2.90 (95% CI: 1.50-5.40), 0.27 (95% CI: 0.14-0.50), 11.0 (95% CI: 4.00-25.00), and 0.84 (95% CI: 0.80-0.87), respectively. For the diagnostic meta-analysis of miR-628-related combination biomarkers, the above six parameters were 0.89 (95% CI: 0.84-0.92), 0.93 (95% CI: 0.82-0.97), 12.30 (95% CI: 4.70-32.50), 0.12 (95% CI: 0.08-0.19), and 100.00 (95% CI: 28.00-354.00), 0.93 (95% CI: 0.90-0.95), respectively. For the prognostic meta-analysis, patients with lower miR-628 had significant shorter overall survival than high expression of miR-628 (HR = 1.553, 95% CI: 1.041-2.318, z = 2.16, P = 0.031).

Conclusions: This study confirms that miR-628 may be a promising biomarker for cancer diagnosis and prognosis. Expertly, microRNAs combination biomarkers could be a new alternative for clinical application.