Radiotherapy for renal-cell carcinoma

Extracellular vesicles in renal cell carcinoma: A review of the current landscape and future directions

Liquid biopsy, a minimally invasive biopsy method that uses patient body fluids (e.g., blood, urine, or saliva), is considered a useful biomarker for early diagnosis, monitoring of tumor progression, and evaluating treatment efficacy. Extracellular vesicles (EVs), a diverse group of particles classified according to their size and biosynthetic method, are liquid bilayer structures released from various cells. EVs contain specific information, such as DNA, RNA, and proteins derived from released cells. Consequently, they have attracted attention for use in liquid biopsy. EV-derived microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) are useful biomarkers for cancer diagnosis, tumor progression, and drug treatment resistance. Renal cell carcinoma (RCC), one of the most common type of urological cancer, accounts for 90% of all renal tumors. In contrast to prostate cancer, for which a tumor marker has been established, clinically applicable and useful biomarkers remain to be established for RCC. EV-derived miRNAs and lncRNAs have been identified as useful biomarkers in several types of carcinoma for determining the diagnosis and predicting tumor progression, and drug treatment resistance in patients with RCC. The development and identification of biomarkers to diagnose and predict tumor progression in RCC will improve the management and prognosis of patients with RCC. This review focuses on EV-derived miRNAs and lncRNAs and discusses the currently available EV-based biomarkers in RCC and their future prospects.

Stereotactic body irradiation for metastasis from renal carcinoma: A retrospective study

Background

Renal cell carcinoma (RCC) has traditionally been considered to be radioresistant. Response rates are believed to be improved by a high dose of stereotactic body radiotherapy (SBRT). A retrospective analysis was conducted of patients treated with SBRT for metastatic disease from RCC.

Material and methods

We reviewed records from 20 patients who underwent SBRT for a total of 30 RCC metastases from 2015 to 2020. Patients were included who had a confirmed primary RCC and radiographic evidence of metastasis, either synchronous or metachronous. The most common SBRT fractionation was 30 Gy in 3 fractions.

Results

Median age was 60 years (range, 40-77 years) and 60% were male. After a median follow-up of 18 months (range, 3-36 months), overall survival was estimated to be 85% and 70%, at 1 and 2 years, respectively, and local control at 2 years was 83.33%. Only 5 patients had documented progression of disease, all of whom received biologically effective dose inferior to 100 Gy, and no patients treated with a higher biologically effective dose had disease, which progressed. The most common acute toxicity was grade 1 fatigue (20%). No grade 3 or higher acute toxicity occurred.

Conclusions

Treatment with SBRT in patients with RCC metastases yielded a high local control rate, promising survival rate, and low toxicity.

Stereotactic Body Radiation Therapy Alone or in Combination with Immunotherapy in Kidney Cancer: A Systematic Review

BACKGROUND AND OBJECTIVE

Despite its radioresistant reputation, renal cell carcinoma (RCC) is sensitive to high dose per fraction stereotactic ablative body radiotherapy (SABR). As SABR also triggers immunomodulatory effects, a combination of SABR and immunotherapy for RCC might improve patient outcomes. The current systematic review will discuss all prospective studies on SABR alone or combined with immunotherapy.

METHODS

A systematic review was conducted in January 2025 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement on the PubMed and Cochrane databases. Thirty-eight studies were included in this review.

KEY FINDINGS AND LIMITATIONS

In the primary setting, 15 prospective studies have proved SABR to be a valuable alternative for (partial) nephrectomy for high-risk or medically inoperable patients, with good tolerability and excellent local control. No prospective studies have reported on SABR combined with immunotherapy in nonmetastatic patients. In the oligometastatic setting, two phase 2 trials have investigated SABR in lieu of systemic treatment. This showed encouraging results, with the majority of patients being free from systemic therapy at 1 yr. SABR combined with immunotherapy in the metastatic setting has been investigated in multiple phase 1 and 2 trials, where the most promising option seems to be SABR to multiple-preferentially all-lesions. Cytoreductive SABR and SABR to oligoprogressive lesions combined with immunotherapy are attractive future strategies.

CONCLUSIONS AND CLINICAL IMPLICATIONS

SABR is a valid alternative in localised RCC when (partial) nephrectomy is not an option. In the metastatic setting, several early-phase trials have investigated SABR alone and in combination with immunotherapy, warranting future large, randomised trials.

Optimization of immunotherapy-based combinations for metastatic renal cell carcinoma: A network meta-analysis

BACKGROUND

Despite numerous meta-analyses comparing the efficacy and safety of immunotherapy-based combination therapies, the optimal therapeutic combinations remain unclear. This study aims to evaluate the optimal application of all immunotherapy-based combination therapy for advanced/metastatic renal cell carcinoma, focusing on efficacy and safety.

METHODS

We systemically searched the Web of Science, Cochrane Library, and PubMed for studies regarding the first-line immunotherapy-based combination therapy in patients with advanced or metastatic renal cell carcinoma until April 15, 2024. We used network meta-analysis using a random effect model to facilitate direct and indirect treatment comparisons across outcomes.

RESULTS

Seven clinical studies, including 5542 patients with metastatic renal cell carcinoma, were included in the network meta-analysis analysis. Regarding progression-free survival and overall survival, combined Toripalimab + Axitinib significantly outperformed other immunotherapy-based combination therapies. This regimen significantly improved progression-free survival in the intermediate/poor risk group when stratified by prognosis prediction risks compared to sunitinib alone. For the objective response rate, Avelumab + Axitinib was the most preferred strategy in the favorable-risk group, while Nivolumab + Cabozantinib was favored in the intermediate/poor-risk group compared to other immunotherapy-based combinations. The combinations of Nivolumab + Ipilimumab and Atezolizumab + Bevacizumab had favorable safety profiles.

CONCLUSIONS

Immunotherapy-based combination therapies significantly improved progression-free survival, overall survival and objective response rate in patients with metastatic renal cell carcinoma compared to sunitinib monotherapy. However, careful monitoring and personalized treatment strategies are required to balance efficacy and safety in patients with underlying conditions. Future research should focus on optimizing treatment protocols and elucidating the mechanisms of adverse events.

The Transcription Factor ATF2 Accelerates Clear Cell Renal Cell Carcinoma Progression Through Activating the PLEKHO1/NUS1 Pathway

Clear cell renal cell carcinoma (ccRCC) is a common malignant cancer with high mortality rate. Activating transcription factor 2 (ATF2) and pleckstrin homology domain containing O1 (PLEKHO1) were reported to participate in numerous cancers. However, their roles and the detailed mechanisms in ccRCC development remain largely unknown. RT-qPCR and western blot were used to measure the levels of PLEKHO1, ATF2, and nuclear undecaprenyl pyrophosphate synthase 1 (NUS1). Cell proliferation, apoptosis, invasion, migration and stemness were evaluated using CCK-8 assay, flow cytometry, transwell invasion assay, wound-healing assay and sphere formation assay, respectively. Dual-luciferase reporter assay was conducted to verify the relationship between ATF2 and PLEKHO1. The interaction between PLEKHO1 and NUS1 was proved by Co-IP assay. Xenograft models were utilized to evaluate the tumorigenic capability of ccRCC cells upon PLEKHO1 knockdown. PLEKHO1, ATF2 and NUS1 expression were significantly elevated in ccRCC, and PLEKHO1 might be a prognosis biomarker for ccRCC. PLEKHO1 depletion significantly inhibited cell proliferation, invasion, migration, stemness, and induced cell apoptosis in ccRCC cells. ATF2 activated PLEKHO1 expression via transcription regulation, and PLEKHO1 overexpression could reverse the suppressive effects of ATF2 knockdown on the malignant behaviors of ccRCC cells. Moreover, PLEKHO1 directly bound to NUS1, and PLEKHO1 depletion markedly restrained ccRCC progression through targeting NUS1 in vitro and in vivo. Our findings suggested that ATF2 transcriptionally activated PLEKHO1 to promote the development of ccRCC via regulating NUS1 expression.

Stereotactic Body Radiation Therapy (SBRT) for Renal Cell Carcinoma with Inferior Vena Cava Tumor Thrombus

The prognosis for untreated renal cell carcinoma (RCC) with inferior vena cava tumor thrombus (IVC TT) is poor, and the only curative treatment option is extirpative surgery. However, radical nephrectomy with IVC thrombectomy is associated with high rates of morbidity and mortality. Historically, RCC was considered radioresistant, but it appears to be sensitive to higher doses per fraction. Stereotactic body radiation therapy (SBRT), which delivers high ablative radiation doses to focal targets, has been shown to be an effective treatment option for both non-metastatic and metastatic RCC. Emerging data also suggest its role in the management of RCC with IVC TT. This article reviews the available evidence on the use of SBRT in RCC patients with IVC TT, considering its application as curative, palliative, and neoadjuvant therapy.

Results of Stereotactic Body Radiation Therapy for Primary Renal Cell Carcinoma in a Large Multicenter Series

BACKGROUND AND OBJECTIVE

For inoperable patients, stereotactic body radiation therapy (SBRT) is a noninvasive treatment approach for primary renal cell carcinoma (RCC). We aimed to evaluate local control (LC) of primary RCC treated with SBRT.

METHODS

This multicenter retrospective study involved 16 centers in Australia, France, Italy, and the Netherlands. The primary endpoint was the LC probability, and the secondary endpoints were progression-free survival, overall survival (OS), cumulative incidence of cancer-related deaths, toxicities, and renal function evolution after SBRT.

KEY FINDINGS AND LIMITATIONS

A total of 144 patients, treated between 2008 and 2020, with a median follow-up of 43 mo (interquartile range [IQR], 24.0-81.2), were included. The median age was 76 yr (IQR, 67.0-82.0) and the median tumor size was 4.4 cm (IQR, 3.3-5.6). The median baseline estimated glomerular filtration rate (eGFR) was 60 ml/min/1.73 m2. Of the patients, 40% had mild to moderate eGFR (30-60 ml/min). The two main treatment regimens were 42 Gy in three fractions and 26 Gy in one fraction. The LC probability was 98% at 1 yr (95% confidence interval [CI], 94-99) and 96% (95% CI, 92-99) at 5 yr. The median OS was 58 mo and the cumulative incidence of cancer-related deaths was 8% (95% CI, 3-15) at 5 yr. Seventy-one patients (49%) experienced at least one toxicity, including grade 1 in the majority (32%), grade 2 (14%), and grade 3 (1%). Two patients (1%) underwent dialysis (grade 4). The median eGFR loss was -7 ml/min (IQR, -17; 0) at the last follow-up.

CONCLUSIONS AND CLINICAL IMPLICATIONS

This large series of primary RCC treated with SBRT demonstrates excellent LC and renal function preservation, and is associated with an acceptable toxicity profile. SBRT is an alternative treatment for inoperable patients.

Efficacy of innovative systemic treatments in combination with radiotherapy for bone metastases: a GEMO (the European Study Group of Bone Metastases) state of the art

The management of bone metastases (BoM) requires a multidisciplinary approach to prevent complications, necessitating updated knowledge in light of the rapid advancements in systemic treatments and surgical, interventional radiology or radiation techniques. This review aims to discuss efficacy of new systemic treatments on BoM, the benefits of radiotherapy adjunction, and the optimal methods for combining them. Preliminary evidence suggesting reduced efficacy of immune checkpoint inhibitors (ICI), and several multi-kinase inhibitors regarding BoM may encourage early use of radiotherapy (RT). Systemic treatment efficacy modulation by RT and ablative RT strategies are explored. Concerns for increased side effects for several kinase inhibitors and double ICI in combination with RT imply suspending those systemic treatments during RT. Various timing strategies to combine prostate hormone therapies and RT are developed. Emerging internal vectorized radiotherapy molecules necessitate developing new combination strategies with RT. Further prospective data collection and comparative trials should be encouraged.

circASAP1 induces renal clear cell carcinoma ferroptosis by binding to HNRNPC and thereby regulating GPX4

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) represents the most prevalent subtype, accounting for nearly 80% of all RCC cases. Recent research has shown that high expression of circular non-coding RNA (circRNA) is associated with poor prognosis in patients with renal clear cell carcinoma (ccRCC), however, the underlying mechanism remains unclear.

METHODS

After analysing self-sequenced renal cancer and paracancer circRNA sequencing data and comparing it with the GEO public database, we discovered that circASAP1 expression was significantly up-regulated in renal cancers. We also tested circASAP1 levels in 102 renal cancer patients and found that high expression of circASAP1 was associated with poor prognosis and metastasis. The interaction between circASAP1, HNRNPC and their downstream target genes was confirmed through experiments such as RNA pull-down, RIP and fluorescence in situ hybridisation. A series of in vitro and in vivo functional experiments were performed to verify the effects of circASAP1 on RCC proliferation and metastasis.

RESULTS

Circular RNA sequencing analysis revealed that circASAP1 expression was markedly elevated in ccRCC, with a significant association observed between elevated circASAP1 expression and poor prognosis and metastasis. Actinomycin D, RNase R, as well as fluorescence in situ hybridization (FISH) analyses revealed the ring structure and cytoplasmic localization of circASAP1. High circASAP1 expression was associated with ccRCC cell proliferative viability, invasion, and metastasis in CCK-8, transwell, plate cloning, and EdU experiments. Interaction of circASAP1 with HNRNPC and their downstream target genes was confirmed by RNA pull-down, RNA immunoprecipitation, FISH, silver staining, and mass spectrometry. Experiments using truncated isoforms demonstrated that amino acids 16-87 of HNRNPC bound circASAP1. Proteins altered by circASAP1 were enriched in the ferroptosis pathway on the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis.

CONCLUSIONS

The relationship between circRNA and the ASAP1/HNRNPC/GPX4 axis was demonstrated by experimental data, which was further confirmed by rescue experiments. circASAP1 influenced tumor growth and ferroptosis in animal experiments and predicted the prognosis of patients with ccRCC. The circASAP1/HNRNPC/GPX4 axis provides novel directions and potential targets for RCC treatment.

Stereotactic Body Therapy for Urologic Cancers-What the Urologist Needs to Know

BACKGROUND

stereotactic ablative body radiotherapy (SABR) is a disruptive radiation therapy technique which is increasingly used for the treatment of urologic cancers. The aim of this narrative review is to provide an overview on the current landscape of SABR in urologic cancers and highlight advancements on the horizon.

METHODS

a narrative review of the contemporary role of SABR in urologic cancers is conducted.

RESULTS

in localised prostate cancer, SABR boasts excellent tumour control and biochemical control, with acceptable GU and GI toxicity. Its comparison to laparoscopic radical prostatectomy is currently ongoing. SABR appears to be practical for metastasis-directed therapy in metastatic prostate cancer, with good local control and a low toxicity profile, either alone or in combination with ADT. In localised RCC, SABR offers adequate local control with a modest impact on renal function in patients unfit for surgical management. Its role in metastatic RCC is much more established, where it has been shown to be superior to conventional radiotherapy. Emerging evidence suggests that SABR has a role in delaying systemic therapy whilst maintaining QOL and overall survival. Intriguingly, in metastatic prostate cancer and metastatic RCC, SABR results in a cytoreductive and immunomodulatory 'abscopal effect', a focus of current investigations.

CONCLUSIONS

SABR has emerged as a safe, effective, and feasible treatment for urologic cancers. Urologists should be aware of its increasing use in localised prostate cancer and metastatic RCC, with good oncological outcomes combined with acceptable toxicity. In addition, SABR holds promise for both metastatic prostate cancer and localised RCC treatment in terms of toxicity and oncological outcomes.

First-line Systemic Therapy Following Adjuvant Immunotherapy in Renal Cell Carcinoma: An International Multicenter Study

BACKGROUND AND OBJECTIVE

Adjuvant pembrolizumab significantly improved overall survival (OS) in renal cell carcinoma (RCC), but real-world data on sequential treatment are scarce. We sought to evaluate the clinical outcomes of first-line (1L) systemic therapy following adjuvant immune oncology (IO)-based regimens.

METHODS

A retrospective study including patients with recurrent RCC following adjuvant IO across 29 international institutions was conducted. The primary endpoint was progression-free survival (PFS) on 1L systemic therapy estimated using the Kaplan-Meier method. Preplanned subanalyses of clinical outcomes by type of 1L systemic therapy, recurrence timing, and International Metastatic RCC Database Consortium (IMDC) risk groups were performed. Treatment-related adverse events leading to treatment discontinuation, dose reduction, or corticosteroid use were assessed.

KEY FINDINGS AND LIMITATIONS

A total of 94 patients were included. Most received adjuvant pembrolizumab (n = 37, 39%), atezolizumab (n = 28, 30%), or nivolumab + ipilimumab (n = 15, 16%). The cohort included 49 (52%) patients who had recurrence within 3 mo of the last adjuvant IO dose, whereas 45 (48%) recurred beyond 3 mo. Bone metastases were significantly higher in tumors recurring at <3 mo (10/49, 20%) than those recurring at >3 mo (1/45, 2.2%; p = 0.008). Most patients received 1L vascular endothelial growth factor-targeted therapy (VEGF-TT; n = 37, 39%), IO + VEGF-TT (n = 26, 28%), or IO + IO (n = 12, 13%). The remaining underwent local therapy. The median follow-up for the 1L systemic therapy cohort was 15 mo. The 18-mo PFS and OS rates were 45% (95% confidence interval [CI]: 34-60) and 85% (95% CI: 75-95), respectively. Treatment-related adverse events occurred in 32 (42%) patients and included skin toxicity (n = 7, 9.2%), fatigue (n = 6, 7.9%), and diarrhea/colitis (n = 4, 5.3%). Limitations included selecting patients from large academic centers and the short follow-up period.

CONCLUSIONS AND CLINICAL IMPLICATIONS

A subset of patients with recurrent RCC following adjuvant IO respond to systemic therapies, including VEGF-TT and IO-based regimens. Notably, patients with favorable-risk disease may derive more benefit from VEGF-TT than from IO therapies in this setting. Future approaches utilizing radiographic tools and biomarker-based liquid biopsies are warranted to detect occult metastatic disease and identify candidate patients for adjuvant IO therapy.

PATIENT SUMMARY

Adjuvant pembrolizumab significantly improved overall survival in renal cell carcinoma (RCC). There are limited data on clinical outcomes after the recurrence of RCC tumors following adjuvant immunotherapy. In this study, we find that patients respond to subsequent systemic therapies across different treatment options.

DLX5 Promotes Radioresistance in Renal Cell Carcinoma by Upregulating c-Myc Expression

BACKGROUND

Renal cell carcinoma (RCC) is a prevalent and aggressive kidney cancer with notable metastatic potential. While radiotherapy is effective for treating metastatic RCC, the emergence of radioresistance presents a major challenge. This study explores the role of DLX5, previously identified as an oncogene in various cancers, in the development of radioresistance in RCC.

METHODS

Distal-less homeobox 5 (DLX5) expression was measured using western blot analysis. To study the effects of DLX5, its expression was knocked down in 786-O and Caki-1 RCC cell lines through si-DLX5 transfection, and the impact of DLX5 on RCC cell proliferation and radioresistance was assessed using cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU) incorporation assay, flow cytometry, colony formation, immunofluorescence, and western blot assays. The underlying mechanisms were explored through western blot, colony formation, and CCK-8 assays. In vivo effects were examined using a xenograft mouse model.

RESULTS

In silico results showed increased DLX5 levels in RCC tissues. Similarly, DLX5 expression was elevated in RCC cell lines. Silencing DLX5 reduced RCC cell proliferation and induced apoptosis in vitro. Additionally, DLX5 knockdown decreased radioresistance and increased DNA damage in RCC cells. Mechanistic studies revealed that DLX5 promotes radioresistance through the upregulation of c-Myc. In vivo, DLX5 silencing impeded tumor growth and reduced radioresistance.

CONCLUSION

DLX5 contributes to RCC cell growth and radioresistance by upregulating c-Myc expression, highlighting its potential as a target for overcoming radioresistance in RCC.

Palliative care of proximal femur metastatic disease and osteolytic lesions: results following surgical and radiation treatment

BACKGROUND

Femoral bone metastases (FBM) or lesions (FBL) can lead to loss of mobility and independence due to skeletal-related events (SRE), e.g. pain, deformity and pathological fractures. Aim of this study was to analyze effects of radiotherapy and surgery, different surgical techniques and complications on disease-specific survival (DSS).

METHODS

Patients who underwent palliative therapy for FBM or FBL between 2014 and 2020 were retrospectively analyzed. Chi-square test was used to detect intergroup differences. Survival was calculated using Kaplan-Meier method, Cox regression and compared using log-rank test. Complications were evaluated using Chi-Square test.

RESULTS

145 patients were treated for proximal femoral BM/BL or pathologic fractures (10 bilaterally). Three groups were classified: surgery only (S, n = 53), surgery with adjuvant radiation (S + RT, n = 58), and primary radiation only (RT, n = 44). Most common primary tumors were breast (n = 31), prostate (n = 27), and non-small cell lung cancer (n = 27). 47 patients underwent surgery for an impending, 61 for a manifest pathological fracture. There were no significant differences in DSS between the 3 groups (S = 29.8, S + RT = 32.2, RT = 27.1 months), with the S + RT group having the longest one-year survival. Local complications occurred in 25 of 145 patients after a mean interval of 9.9 months.

CONCLUSION

Due to the steadily increasing incidence and survival of patients with FBM/FBL, indication for prevention and treatment of painful and immobilizing SREs should be critically assessed. Surgical treatment should always be performed with maximum stability and, whenever possible, adjuvant RT.

Current State of Stereotactic Body Radiation Therapy for Genitourinary Malignancies

ABSTRACT

Stereotactic body radiation therapy (SBRT) involves the delivery of high-dose, highly precise radiation therapy to focal sites of gross tumor involvement. Recent advances in radiation planning and image guidance have facilitated rapid growth in the evidence for and use of SBRT, particularly for genitourinary malignancies, where the underlying radiobiology often suggests greater tumor sensitivity to SBRT than to conventionally fractionated radiation. Here, we review the evolution of SBRT for patients with prostate adenocarcinoma and renal cell carcinoma. We discuss state-of-the-art trials, indications, and future directions in the SBRT-based management of both localized and metastatic disease. With rapidly growing enthusiasm and evidence, clinical and translational research efforts on the biology and outcomes of SBRT over the coming decade will be crucial to refining the indications, technical approach, and synergistic combinations of SBRT with highly active systemic therapies and improve the efficacy and quality-of-life outcomes for patients with genitourinary malignancies.

Changes in the overall survival of patients with metastatic renal cell carcinoma in the era of immune-checkpoint inhibitors

BACKGROUND

The advent of immune checkpoint inhibitors (ICI) has brought about a significant transformation in the treatment of immunogenic tumors. On November 23, 2015, the United States Food and Drug Administration approved Nivolumab to treat metastatic renal cell carcinoma (RCC). We aimed to assess potential changes in the survival rates of patients with metastatic RCC at a population level after the approval of Nivolumab.

METHODS

We used data from the latest version of the Surveillance, Epidemiology, and End Results (SEER) database which encompasses data up to the year 2020. We included patients with age ≥ 20 years who were diagnosed with 'distant' RCC from 2011 through 2020. Based on the approval of Nivolumab, the period from 2011 to 2020 was further grouped into 2011-2015 (pre-ICI era) and 2016-2020 (ICI era).

RESULTS

The median overall survival (OS) was 8 months in the pre-ICI era compared to 11 months in the ICI era (log-rank test, χ2 = 102.53, p < 0.001). Patients diagnosed with metastatic RCC in the ICI era had a significantly lower risk of dying [Cox proportional Hazard Ratio of 0.77, 95 % CI (0.74-0.80)] compared to patients diagnosed in the pre-ICI era. Additionally, patients under the age of 75 had a lower risk of death compared to those aged 75 years or older. Patients who received chemotherapy (systemic therapy), radiotherapy, or surgery faced a significantly lower risk of mortality. Individuals with metastasis to the brain, bone, liver, or lung had a significantly higher risk of death than those without metastasis to these locations. Marital status also played a role, as married individuals had a significantly lower risk of death compared to those who were divorced, separated, or widowed at the time of diagnosis. Furthermore, income level influenced survival, with patients earning a median annual household income of more than USD 75,000 exhibiting a significantly lower risk of mortality compared to those earning between USD 50,000 and USD 74,000. There was no significant difference in survival observed between non-Hispanic blacks and non-Hispanic whites.

CONCLUSION

The advent of immune checkpoint inhibitors has led to a substantial improvement in the median overall survival of individuals diagnosed with metastatic renal cell carcinoma.

Predictive Factors for Long-Term Disease Control in Systemic Treatment-Naïve Oligorecurrent Renal Cell Carcinoma Treated with Up-Front Stereotactic Ablative Radiotherapy (SABR)

BACKGROUND

Stereotactic ablative radiotherapy (SABR) is emerging as a potential local treatment option for oligometastatic RCC. This study aims to evaluate the efficacy of SABR in patients with oligorecurrent RCC.

METHODS

A total of 50 patients with histologically confirmed RCC underwent SABR for oligorecurrence between 2006 and 2022. Eligible patients had up to five extracranial metastases and were systemic treatment-naïve at the time of irradiation. The primary endpoints of the analysis were overall survival (OS), local control (LC), distant metastasis-free survival (DMFS), and time to systemic therapy initiation.

RESULTS

The median OS was not reached, with 1- and 3-year OS rates of 93.8% and 77.5%, respectively. LC rates at one and three years were 95.8% and 86.5%, respectively. The median time to systemic therapy initiation was 63.8 months, and the median DMFS was 17.9 months, with one- and three-year rates of 63.4% and 36.6%, respectively. Multiple metastases were a negative predictive factor for DMFS (HR 2.39, p = 0.023), whereas lung metastases were associated with a more favorable outcome (HR 0.38, p = 0.011).

CONCLUSIONS

SABR offers a valuable treatment option for oligometastatic RCC, demonstrating significant potential for achieving long-term disease control and delaying the need for systemic therapy.

Disulfidptosis-associated LncRNA signature predicts prognosis and immune response in kidney renal clear cell carcinoma

BACKGROUND

Kidney renal clear cell carcinoma (KIRC) represents a significant proportion of renal cell carcinomas and is characterized by high aggressiveness and poor prognosis despite advancements in immunotherapy. Disulfidptosis, a novel cell death pathway, has emerged as a critical mechanism in various cellular processes, including cancer. This study leverages machine learning to identify disulfidptosis-related long noncoding RNAs (DRlncRNAs) as potential prognostic biomarkers in KIRC, offering new insights into tumor pathogenesis and treatment avenues.

RESULTS

Our analysis of data from The Cancer Genome Atlas (TCGA) led to the identification of 431 DRlncRNAs correlated with disulfidptosis-related genes. Five key DRlncRNAs (SPINT1-AS1, AL161782.1, OVCH1-AS1, AC131009.3, and AC108673.3) were used to develop a prognostic model that effectively distinguished between low- and high-risk patients with significant differences in overall survival and progression-free survival. The low-risk group had a favorable prognosis associated with a protective immune microenvironment and a better response to targeted drugs. Conversely, the high-risk group displayed aggressive tumor features and poor immunotherapy outcomes. Validation through qRT‒PCR confirmed the differential expression of these DRlncRNAs in KIRC cells compared to normal kidney cells, underscoring their potential functional significance in tumor biology.

CONCLUSIONS

This study established a robust link between disulfidptosis-related lncRNAs and patient prognosis in KIRC, underscoring their potential as prognostic biomarkers and therapeutic targets. The differential expression of these lncRNAs in tumor versus normal tissue further highlights their relevance in KIRC pathogenesis. The predictive model not only enhances our understanding of KIRC biology but also provides a novel stratification tool for precision medicine approaches, improving treatment personalization and outcomes in KIRC patients.

DNA Origami-Constructed Nanotapes for Sunitinib Adsorption and Inhibition of Renal Clear Carcinoma Cells

Sunitinib (SUN) is a first-line drug for the treatment of renal clear carcinoma cells by targeting receptor tyrosine kinases (RTK) on the cell membrane. However, the effective delivery of SUN to the cell membrane remains a significant challenge. In this study, we fabricated precisely structured DNA nanotapes with strong surface SUN adhesion, enabling RTK inhibition of renal clear carcinoma cells. In our design, the precisely assembled linear topological six-helical-bundle DNA origami serves as the framework, and positively charged chitosan is adsorbed onto the DNA origami surface, thereby forming DNA nanotapes. The SUN was efficiently loaded onto the surface of the DNA nanotapes by electrostatic interaction. We found that DNA nanotapes exhibit excellent stability in serum. Importantly, DNA nanotapes carrying SUN can achieve prolonged cell membrane retention and inhibit RTK, thereby enhancing cytotoxicity toward 786-0 cells. Taken together, this study provides a promising candidate platform for the efficient delivery of cell membrane receptor inhibitors in anticancer therapy.

Delphi consensus on stereotactic ablative radiotherapy for oligometastatic and oligoprogressive renal cell carcinoma-a European Society for Radiotherapy and Oncology study endorsed by the European Association of Urology

The purpose of this European Society for Radiotherapy and Oncology (ESTRO) project, endorsed by the European Association of Urology, is to explore expert opinion on the management of patients with oligometastatic and oligoprogressive renal cell carcinoma by means of stereotactic ablative radiotherapy (SABR) on extracranial metastases, with the aim of developing consensus recommendations for patient selection, treatment doses, and concurrent systemic therapy. A questionnaire on SABR in oligometastatic renal cell carcinoma was prepared by a core group and reviewed by a panel of ten prominent experts in the field. The Delphi consensus methodology was applied, sending three rounds of questionnaires to clinicians identified as key opinion leaders in the field. At the end of the third round, participants were able to find consensus on eight of the 37 questions. Specifically, panellists agreed to apply no restrictions regarding age (25 [100%) of 25) and primary renal cell carcinoma histology (23 [92%] of 25) for SABR candidates, on the upper threshold of three lesions to offer ablative treatment in patients with oligoprogression, and on the concomitant administration of immune checkpoint inhibitor. SABR was indicated as the treatment modality of choice for renal cell carcinoma bone oligometatasis (20 [80%] of 25) and for adrenal oligometastases 22 (88%). No consensus or major agreement was reached regarding the appropriate schedule, but the majority of the poll (54%-58%) retained the every-other-day schedule as the optimal choice for all the investigated sites. The current ESTRO Delphi consensus might provide useful direction for the application of SABR in oligometastatic renal cell carcinoma and highlight the key areas of ongoing debate, perhaps directing future research efforts to close knowledge gaps.

Immune-related adverse events associated with first-line immune checkpoint inhibitors for metastatic renal cell carcinoma: A systematic review and network meta-analysis

BACKGROUND

In the realm of metastatic renal cell carcinoma (mRCC), the introduction of immune checkpoint inhibitors (ICIs) has revolutionized treatment paradigms. Despite their effectiveness, the comprehensive safety profile of these therapies remains inadequately explored. This network meta-analysis aims to comparing the safety profiles of ICI-based treatments in mRCC, offering vital insights that could lead to the optimization of treatment strategies and improvement of patient care.

METHODS

We conducted a comprehensive search of PubMed, Cochrane Library, Embase, Web of Science, ClinicalTrials.gov, Google Schola, OpenGrey and Scopus through November 1, 2023. The risk of bias assessment was performed using the Risk of Bias version 2 tool.

RESULTS

Seven randomized controlled trials (RCTs) with a total of 5976 patients were included for data analysis. The risk of bias results showed that all RCTs were considered "some concerns". The probability of hypothyroidism (surface under the cumulative ranking curve (SUCRA) = 0.981), hyperthyroidism (SUCRA = 0.983) and dermatologic immune-related adverse events (irAEs) (SUCRA = 0.955) in the Nivolumab + Cabozantinib ranked the first. The Avelumab + Axitinib had the highest incidence of adrenal insufficiency (AI) (SUCRA = 0.976), hepatitis (SUCRA = 0.937) and colitis (SUCRA = 0.864). The Nivolumab + Ipilimumab exhibited the highest incidence of pneumonitis (SUCRA = 0.755). Pembrolizumab + Lenvatinib had the highest incidence of nephritic irAEs (SUCRA = 0.788). The ICI-based group showed a higher incidence of hypothyroidism, hyperthyroidism, dermatologic irAEs, hepatitis and nephritic irAEs than sunitinib. However, the confidence in the evidence regarding the impact of ICI-based treatments on AI, pneumonia, and colitis remains limited.

CONCLUSION

The analysis focused on the probability of irAEs occurrence in each system when mRCC patients were treated with different ICI-based therapies, potentially offering significant value for guiding clinical prevention, early diagnosis, and management of irAEs. The limitations of the study included the potential heterogeneity and low certainty of part of the evidence.

RNA-binding protein IGF2BP2 suppresses metastasis of clear cell renal cell carcinoma by enhancing CKB mRNA stability and expression

Clear cell renal cell carcinoma (ccRCC) is the most prevalent kidney cancer, with a highly aggressive phenotype and poor prognosis. RNA binding proteins (RBPs) play crucial roles in post-transcriptional gene regulation and have been implicated in tumorigenesis. RBPs have the potential to become a new therapeutic target for ccRCC. In this study, we screened and validated that insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) as an RBP, was down-regulated in ccRCC tissues and cell lines. Functionally, we verified that IGF2BP2 significantly suppressed the migration and invasion ability of ccRCC in vitro and in vivo. Mechanistically, RIP-seq and actinomycin D experiments results showed that IGF2BP2 enhanced the expression of Creatine Kinase B (CKB) by binding to CKB mRNA and enhancing its mRNA stability. Thus, IGF2BP2 inhibited ccRCC metastasis through enhancing the expression of CKB. Taken together, these finding suggests that IGF2BP2 is a novel metastasis suppressor of ccRCC and may serve as a potential therapeutic target.

Non-coding RNA and reprogrammed mitochondrial metabolism in genitourinary cancer

Non-coding ribonucleic acids (ncRNAs) have been recently shown to contribute to tumorigenesis by mediating changes in metabolism. ncRNAs act as key molecules in metabolic pathways regulation. The dysregulation of ncRNAs during cancer progression contributes to altered metabolic phenotypes leading to reprogrammed metabolism. Since ncRNAs affect different tumor processes by regulating mitochondrial dynamics and metabolism, in the future ncRNAs can be exploited in disease detection, diagnosis, treatment, and resistance. The purpose of this review is to highlight the role of ncRNAs in mitochondrial metabolic reprogramming and to relate their therapeutic potential in the management of genitourinary cancer.

Stereotactic Body and Conventional Radiotherapy for Painful Bone Metastases: A Systematic Review and Meta-Analysis

Importance

Conventional external beam radiotherapy (cEBRT) and stereotactic body radiotherapy (SBRT) are commonly used treatment options for relieving metastatic bone pain. The effectiveness of SBRT compared with cEBRT in pain relief has been a subject of debate, and conflicting results have been reported.

Objective

To compare the effectiveness associated with SBRT vs cEBRT for relieving metastatic bone pain.

Data Sources

A structured search was performed in the PubMed, Embase, and Cochrane databases on June 5, 2023. Additionally, results were added from a new randomized clinical trial (RCT) and additional unpublished data from an already published RCT.

Study Selection

Comparative studies reporting pain response after SBRT vs cEBRT in patients with painful bone metastases.

Data Extraction and Synthesis

Two independent reviewers extracted data from eligible studies. Data were extracted for the intention-to-treat (ITT) and per-protocol (PP) populations. The study is reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

Main Outcomes and Measures

Overall and complete pain response at 1, 3, and 6 months after radiotherapy, according to the study's definition. Relative risk ratios (RRs) with 95% CIs were calculated for each study. A random-effects model using a restricted maximum likelihood estimator was applied for meta-analysis.

Results

There were 18 studies with 1685 patients included in the systematic review and 8 RCTs with 1090 patients were included in the meta-analysis. In 7 RCTs, overall pain response was defined according to the International Consensus on Palliative Radiotherapy Endpoints in clinical trials (ICPRE). The complete pain response was reported in 6 RCTs, all defined according to the ICPRE. The ITT meta-analyses showed that the overall pain response rates did not differ between cEBRT and SBRT at 1 (RR, 1.14; 95% CI, 0.99-1.30), 3 (RR, 1.19; 95% CI, 0.96-1.47), or 6 (RR, 1.22; 95% CI, 0.96-1.54) months. However, SBRT was associated with a higher complete pain response at 1 (RR, 1.43; 95% CI, 1.02-2.01), 3 (RR, 1.80; 95% CI, 1.16-2.78), and 6 (RR, 2.47; 95% CI, 1.24-4.91) months after radiotherapy. The PP meta-analyses showed comparable results.

Conclusions and Relevance

In this systematic review and meta-analysis, patients with painful bone metastases experienced similar overall pain response after SBRT compared with cEBRT. More patients had complete pain alleviation after SBRT, suggesting that selected subgroups will benefit from SBRT.

Scientific Status Quo of Small Renal Lesions: Diagnostic Assessment and Radiomics

Background: Small renal masses (SRMs) are defined as contrast-enhanced renal lesions less than or equal to 4 cm in maximal diameter, which can be compatible with stage T1a renal cell carcinomas (RCCs). Currently, 50-61% of all renal tumors are found incidentally. Methods: The characteristics of the lesion influence the choice of the type of management, which include several methods SRM of management, including nephrectomy, partial nephrectomy, ablation, observation, and also stereotactic body radiotherapy. Typical imaging methods available for differentiating benign from malignant renal lesions include ultrasound (US), contrast-enhanced ultrasound (CEUS), computed tomography (CT), and magnetic resonance imaging (MRI). Results: Although ultrasound is the first imaging technique used to detect small renal lesions, it has several limitations. CT is the main and most widely used imaging technique for SRM characterization. The main advantages of MRI compared to CT are the better contrast resolution and tissue characterization, the use of functional imaging sequences, the possibility of performing the examination in patients allergic to iodine-containing contrast medium, and the absence of exposure to ionizing radiation. For a correct evaluation during imaging follow-up, it is necessary to use a reliable method for the assessment of renal lesions, represented by the Bosniak classification system. This classification was initially developed based on contrast-enhanced CT imaging findings, and the 2019 revision proposed the inclusion of MRI features; however, the latest classification has not yet received widespread validation. Conclusions: The use of radiomics in the evaluation of renal masses is an emerging and increasingly central field with several applications such as characterizing renal masses, distinguishing RCC subtypes, monitoring response to targeted therapeutic agents, and prognosis in a metastatic context.

A Neurosurgical Perspective on Brain Metastases from Renal Cell Carcinoma: Multi-Institutional, Retrospective Analysis

BACKGROUND

While acknowledging the generally poor prognostic features of brain metastases from renal cell carcinoma (BM RCC), it is important to be aware of the fact that neurosurgery still plays a vital role in managing this disease, even though we have entered an era of targeted therapies. Notwithstanding their initial high effectiveness, these agents often fail, as tumors develop resistance or relapse.

METHODS

The authors of this study aimed to evaluate patients presenting with BM RCC and their outcomes after being treated in the Neurosurgical Department of Clinical Emergency Hospital "Bagdasar-Arseni", and the Neurosurgical Department of the National Institute of Neurology and Neurovascular Diseases, Bucharest, Romania. The study is based on a thorough appraisal of the patient's demographic and clinicopathological data and is focused on the strategic role of neurosurgery in BM RCC.

RESULTS

A total of 24 patients were identified with BM RCC, of whom 91.6% had clear-cell RCC (ccRCC) and 37.5% had a prior nephrectomy. Only 29.1% of patients harbored extracranial metastases, while 83.3% had a single BM RCC. A total of 29.1% of patients were given systemic therapy. Neurosurgical resection of the BM was performed in 23 out of 24 patients. Survival rates were prolonged in patients who underwent nephrectomy, in patients who received systemic therapy, and in patients with a single BM RCC. Furthermore, higher levels of hemoglobin were associated in our study with a higher number of BMs.

CONCLUSION

Neurosurgery is still a cornerstone in the treatment of symptomatic BM RCC. Among the numerous advantages of neurosurgical intervention, the most important is represented by the quick reversal of neurological manifestations, which in most cases can be life-saving.

Survival in Metastatic Renal Cell Carcinoma Treated With Immunotherapy and Stereotactic Radiation Therapy or Immunotherapy Alone: A National Cancer Database Analysis

Purpose

Immunotherapy (IO) has significantly improved outcomes in metastatic renal cell carcinoma (mRCC). Preclinical evidence suggests that responses to IO may be potentiated via immunomodulatory effects of stereotactic radiation therapy (SRT). We hypothesized that clinical outcomes from the National Cancer Database (NCDB) would demonstrate improved overall survival (OS) in patients with mRCC receiving IO + SRT versus IO alone.

Methods and Materials

Patients with mRCC receiving first-line IO ± SRT were identified from the NCDB. Conventional radiation therapy was allowed in the IO alone cohort. The primary endpoint was OS stratified by the receipt of SRT (IO + SRT vs IO alone). Secondary endpoints included OS stratified by the presence of brain metastases (BM) and timing of SRT (before or after IO). Survival was estimated using Kaplan-Meier methodology and compared via the log-rank test.

Results

Of 644 eligible patients, 63 (9.8%) received IO + SRT, and 581 (90.2%) received IO alone. Median follow-up time was 17.7 months (range, 2-24 months). Sites treated with SRT included the brain (71.4%), lung/chest (7.9%), bones (7.9%), spine (6.3%), and other (6.3%). OS was 74.4% versus 65.0% at 1 year and 71.0% versus 59.4% at 2 years for the IO + SRT and IO alone groups, respectively, although this difference did not reach statistical significance (log-rank P = .1077). In patients with BM, however, 1-year OS (73.0% vs 54.7%) and 2-year OS (70.8% vs 51.4%) was significantly higher in those receiving IO + SRT versus IO alone, respectively (pairwise P = .0261). Timing of SRT (before or after IO) did not influence OS (log-rank P = .3185).

Conclusions

Patients with BM secondary to mRCC had prolonged OS with the addition of SRT to IO. Factors such as International mRCC Database Consortium risk stratification, oligometastatic tumor burden, SRT dose/fractionation, and utilization of doublet therapy should be considered in future analyses to better identify patients who may benefit from combined IO + SRT. Further prospective studies are warranted.

The impact of stereotactic ablative radiotherapy on oligoprogressive metastases from renal cell carcinoma

BACKGROUND

Renal cell carcinoma (RCC) represents 80-90% of all kidney tumors and about 15-25% of patients will develop distant metastases. Systemic therapy represents the standard of care for metastatic patients, but stereotactic ablative radiotherapy (SABR) may play a relevant role in the oligoprogressive setting, defined as the progression of few metastases during an ongoing systemic therapy on a background of otherwise stable disease. Aim of the present study was to analyze the outcome of RCC patients treated with SABR on oligoprogressive metastases.

MATERIALS AND METHODS

In this monocenter study, we analyzed patients affected by RCC treated with SABR on a maximum of 5 cranial or extracranial oligoprogressive sites of disease. Endpoints were overall survival (OS), progression-free survival (PFS), and toxicity.

RESULTS

We included 74 oligoprogressions (26 intracranial and 48 extracranial) and 57 SABR treatments in 44 patients. Most common concomitant treatments were sunitinib (28, 49.1%), pazopanib (12, 21.0%) and nivolumab (11, 19.3%). Median follow-up was 19.0 months, and 1- and 2-year OS rates were 79.2% and 57.3%, respectively. Repeated SABR was a positive predictive factor for OS (p = 0.034). Median PFS was 9.8 months, with 1- and 2-year rates of 43.2% and 25.8%. At multivariable analysis, disease-free interval (p = 0.022) and number of treated metastases (p = 0.007) were significant for PFS. About 80% of patients continued the ongoing systemic therapy 1- and 2-years after SABR with no grade 3 or 4 toxicities.

CONCLUSIONS

we confirmed the efficacy and safety of SABR for oligoprogression from RCC, with the potential to ablate resistant metastases and to prolong the ongoing systemic therapy.

Beyond the Knife in Renal Cell Carcinoma: A Systematic Review-To Ablate or Not to Ablate?

Intensified systemic therapy in metastatic renal cell carcinoma (mRCC) has led to improved patient outcomes. Patients commonly require local control of one or a few metastases. The aim was to evaluate metastasis-directed ablative therapies in extracranial mRCC. Two databases and one registry were searched, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach, for all prospective and matched-pair case-control mRCC studies of radiofrequency ablation (RFA), cryotherapy, microwave ablation (MWA), and stereotactic body radiotherapy (SBRT). Eighteen studies were identified. Fourteen investigated SBRT in 424 patients. Four thermal ablation studies were identified: two cryotherapy (56 patients) and two RFA studies (90 patients). The median participant number was 30 (range 12-69). The combined median follow-up was 17.3 months (range 8-52). Four SBRT studies reported local control (LC) at 12 months, median 84.4% (range 82.5-93). Seven studies (six SBRT and one cryotherapy) reported an LC rate of median 87% (79-100%). Median overall survival (OS) was reported in eight studies (five SBRT, two cryotherapy, and one RFA) with a median of 22.7 months (range 6.7-not reached). Median progression-free survival was reported in seven studies (five SBRT, one cryotherapy, and one RFA); the median was 9.3 months (range 3.0-22.7 months). Grade ≥ 3 toxicity ranged from 1.7% to 10%. SBRT has excellent local control outcomes and acceptable toxicity. Only four eligible thermal ablative studies were identified and could not be compared with SBRT. Translationally rich definitive studies are warranted.

Effectiveness of immune checkpoint inhibitors in combination with stereotactic radiosurgery for patients with brain metastases from renal cell carcinoma: inverse probability of treatment weighting using propensity scores

OBJECTIVE

Stereotactic radiosurgery (SRS) is the mainstay for treating brain metastases (BMs) from renal cell carcinoma (RCC). In recent years, immune checkpoint inhibitors (ICIs) have been applied to metastatic RCC and have contributed to improved outcomes. The authors investigated whether SRS with concurrent ICIs for RCC BM prolongs overall survival (OS) and improves intracranial disease control and whether there are any safety concerns.

METHODS

Patients who underwent SRS for RCC BMs at the authors' institution between January 2010 and January 2021 were included. Concurrent use of ICIs was defined as no more than 3 months between SRS and ICI administration. The time-to-event analysis of OS and intracranial progression-free survival (IC-PFS) between the groups with and without ICIs (ICI+SRS and SRS, respectively) was performed using inverse probability of treatment weighting (IPTW) based on propensity scores (PSs) to control for selection bias. Four baseline covariates (Karnofsky Performance Scale score, extracranial metastases, hemoglobin, and number of BMs) were selected to calculate PSs.

RESULTS

In total, 57 patients with 147 RCC BMs were eligible. The median OS for all patients was 9.1 months (95% CI 6.0-18.9 months), and the median IC-PFS was 4.4 months (95% CI 3.1-6.8 months). Twelve patients (21%) received concurrent ICIs. The IPTW-adjusted 1-year OS rates in the ICI+SRS and SRS groups were 66% and 38%, respectively (HR 0.30, 95% C 0.13-0.69; p = 0.005), and the IPTW-adjusted 1-year IC-PFS rates were 52% and 16%, respectively (HR 0.30, 95% CI 0.14-0.62; p = 0.001). Severe tumor hemorrhage (Common Terminology Criteria for Adverse Events [CTCAE] grade 4 or 5) occurred immediately after SRS in 2 patients in the SRS group. CTCAE grade 2 or 3 toxicity was observed in 2 patients in the ICI+SRS group and 5 patients in the SRS group.

CONCLUSIONS

Although the patient number was small and the analysis preliminary, the present study found that SRS with concurrent ICIs for RCC BM patients prolonged survival and provided durable intracranial disease control, with no apparent increase in treatment-related adverse events.

Stereotactic body radiotherapy and tyrosine kinase inhibitors in patients with oligometastatic renal cell carcinoma: a multi-institutional study

PURPOSE

Few studies have determined the viability of stereotactic body radiotherapy (SBRT) and tyrosine kinase inhibitors (TKIs) in the treatment of metastatic renal cell carcinoma (mRCC). We examined the results of RCC patients who had five or fewer lesions and were treated with TKI and SBRT.

METHODS

The clinical data of 42 patients with 96 metastases treated between 2011 and 2020 were retrospectively evaluated. The prognostic factors predicting overall survival (OS) and progression-free survival (PFS) were assessed in uni- and multivariable analyses.

RESULTS

Median follow-up and time between TKI therapy and SBRT were 62.3 and 3.7 months, respectively. The 2‑year OS and PFS rates were 58.0% and 51.3%, respectively, and 2‑year local control rate was 94.1% per SBRT-treated lesion. In univariable analysis, the time between TKI therapy and SBRT and treatment response were significant prognostic factors for OS and PFS. In multivariable analysis, a time between TKI therapy and SBRT of less than 3 months and complete response were significant predictors of better OS and PFS. Only 12 patients (28.6%) had a systemic treatment change at a median of 18.2 months after SBRT, mostly in patients with a non-complete treatment response after this therapy. Two patients (4.8%) experienced grade III toxicity, and all side effects observed during metastasis-directed therapy subsided over time.

CONCLUSION

We demonstrated that SBRT in combination with TKIs is an effective and safe treatment option for RCC patients with ≤ 5 metastases. However, distant metastasis was observed in 60% of the patients, indicating that distant disease control still has room for improvement.

Stereotactic body radiation therapy for kidney cancer. Where do we stand?

At present, surgery is still the gold standard for the local treatment of renal cancer. Nonetheless, in several clinical scenarios, stereotactic body radiation therapy (SBRT) also known as stereotactic ablative body radiotherapy (SABR) is emerging as a highly effective ablative technique in fragile patients and those with significant comorbidities, as well as in cases where percutaneous therapy (cryoablation or radiofrequency) is not viable. However, considering the intrinsic radioresistance of renal tumors, the optimal treatment schemes have not been established. In oligometastatic patients, it has been reported that the control of the oligometastases can be a potentially curable approach. Being a technique than can be administered exclusively or in combination with systemic therapy, treatment individualization based on patient characteristics is key. Another scenario under investigation is oligoprogression, where SBRT offers the possibility of delaying further lines of systemic therapy by eliminating subclones of resistant tumor with ablative doses, with the additional opportunity of stimulating the immune system (immunomodulatory role). In this review, we have conducted an analysis of recently published studies that test the role of this technique in different clinical scenarios of this disease. We have found promising results that make SBRT a potent therapeutic approach with low toxicity. We also comment on ongoing studies that will generate the necessary evidence needed for the implementation of this technique in our daily clinical practice.

The role of cytoreductive nephrectomy in metastatic renal cell carcinoma in the targeted therapy and immunological therapy era: a systematic review and meta-analysis

BACKGROUND

The role of cytoreductive nephrectomy (CN) in metastatic renal cell carcinoma (mRCC) remains controversial. In addition, several unanswered questions regarding the use of CN remain: Can CN provide survival benefits for patients with mRCC? Where do we place CN in the treatment sequence paradigm among patients with mRCC? How do we best stratify patients with mRCC for CN therapy?

MATERIALS AND METHODS

A search strategy was conducted in the PubMed, Embase, and Web of Science databases. Studies were included only in the English language. The risk of bias assessment was made by using ROBINS-I (Risk of Bias in Nonrandomized Studies of Interventions) and RoB 2 (Risk of Bias 2) tools. The expected outcomes were analyzed by meta-analyses with the fixed-effects model or random effects model, including overall survival (OS) and progression-free survival (PFS). The measure of effect was the hazard ratio (HR) with a 95% CI, and sensitivity analysis was conducted to assess the reliability of the final results.

RESULTS

A total of 30 studies were included in the qualitative analysis. The HR for OS was 0.55 (95% CI, 0.50-0.61), and PFS was 0.72 (95% CI, 0.66-0.80), favoring CN compared with no CN. The upfront CN plus targeted therapy (TT) group had superior OS (HR, 0.57; 95% CI, 0.51-0.64) compared with the TT alone group. Furthermore, upfront CN plus systemic therapy (ST) was associated with numerically inferior OS compared with ST plus deferred CN in patients with mRCC (HR, 1.31; 95% CI, 0.98-1.74). Finally, the leave-one-out test of sensitivity analysis indicated that the results of this meta-analysis were stable and reliable in the overall HR estimates for these survival outcomes.

CONCLUSIONS

First, CN was associated with better survival than no CN in patients with mRCC. Second, the combination of upfront CN and TT may lead to superior survival outcomes compared to TT alone in patients with mRCC. Survival outcomes were similar between the upfront CN+ST group and the ST+deferred CN group in patients with mRCC. Exact patient selection based on baseline prognostic factors is needed to promise maximal survival for patients with mRCC.

Stereotactic ablative radiotherapy for unresectable inferior vena cava tumor thrombus in a patient with renal cell carcinoma: a case report

PURPOSE

Treatment options for renal cell carcinoma (RCC) with inferior vena cava tumor thrombus (IVC-TT) are limited and carry substantial risks. Currently, there are no standard treatment options in the setting of recurrent or unresectable RCC with IVC-TT.

METHODS

We report our experience of treating an IVC-TT RCC patient with stereotactic body radiation therapy (SBRT).

RESULTS

This 62-year-old gentleman presented renal cell carcinoma with IVC-TT and liver metastases. Initial treatment consisted of radical nephrectomy and thrombectomy followed by continuous sunitinib. At 3 months, he developed an unresectable IVC-TT recurrence. A fiducial marker was implanted into the IVC-TT by catheterization. New biopsies were performed at the same time, demonstrating a recurrence of the RCC. SBRT consisted of 5 fractions of 7 Gy to the IVC-TT with excellent initial tolerance. He subsequently received anti-PD1 therapy (nivolumab). At 4 years follow-up, he is doing well with no IVC-TT recurrence and no late toxicity.

CONCLUSION

SBRT appears to be a feasible and safe treatment for IVC-TT secondary to RCC in patients who are not candidates for surgery.

Stereotactic Body Radiotherapy for Kidney Cancer: Ready for Prime Time?

The standard treatment for renal cell carcinoma (RCC) is surgery. However, a number of patients will not be candidates for surgical treatment or will reject this therapeutic approach. Therefore, alternative approaches are required. Historically, radiotherapy has been considered an ineffective treatment for RCC due to the radioresistance of renal tumour cells to conventional fractionation and the increased rate of toxicity. Stereotactic body radiotherapy (SBRT) is a radiotherapy technique that provides a non-invasive ablative treatment with remarkable rates of local control in both primary tumours and metastases in several locations, with a low associated morbidity due to the highly conformal dose and the use of image-guided techniques. Current evidence shows that a higher dose per fraction, achieving a higher biological effective dose, can overcome the radioresistance of RCC cells. Therefore, SBRT, as well as the combination of SBRT and new emerging immune therapies, has a potential role in the local treatment of primary RCC and oligometastatic RCC patients.

Approaches to Oligometastatic Renal Cell Carcinoma

PURPOSE OF REVIEW

This study aims to gather the current state of the literature about therapeutic approaches and management of oligometastatic renal cell carcinoma.

RECENT FINDINGS

Two recent stereotactic body radiotherapy (SBRT) studies gained attention and offered a promising outcome alone or in association with antineoplastic drugs especially in oligometastatic renal cell carcinoma. If one can consider evidence-based medicine as the sole therapeutic option, many unresolved questions are still pending. Thus, therapeutic approaches in oligometastatic renal cell carcinoma are still working. Further phase III clinical trials are urgently needed to validate the last 2 phase II involving SBRT and improve knowledge for defining the right care to the right patient at the right time. In addition, a discussion in a disciplinary consultation meeting remains essential to validate the arrangement between systemic treatments and focal treatments that will best benefit the patient.

Expression analysis of hsa_circ_0020397, hsa_circ_0005986, hsa_circ_0003028, and hsa_circ_0006990 in renal cell carcinoma

Renal cell carcinoma (RCC) is a prevalent heterogeneous kidney cancer. So far, different genes have been reported for RCC development. However, its particular molecular mechanism remains unclear. Circular RNAs (circRNAs), a class of non-coding RNAs, are involved in numerous biological processes in different malignancies such as RCC. This study aims to assess the expression and underlying mechanism of four circRNAs (hsa_circ_0020397, hsa_circ_0005986, hsa_circ_0003028, hsa_circ_0006990) with possible new roles in RCC. In the experimental step, we investigated the expression of these four circRNAs in our RCC samples using quantitative real-time polymerase chain reaction. In the bioinformatics step, the differential expressed mRNAs (DEmRNAs), and miRNAs (DEmiRNAs) were obtained from the GEO datasets using the GEO2R tool. A protein-protein interaction network was constructed using the STRING database, and hub genes were identified by Cytoscape. Molecular pathways associated with hub genes were detected using KEGG pathway enrichment analysis. Then, we utilized the ToppGene database to detect the relationships between DEmiRNAs and hub genes. Furthermore, interactions between circRNAs and DEmiRNAs were predicted by the StarBase and circinteractome databases. Finally, a circRNA-DEmiRNA-hub gene triple network was constructed. Our results revealed that the expression of hsa_circ_0020397, hsa_circ_0005986, and hsa_circ_0006990 was downregulated in RCC tissues. Moreover, these circRNAs had a significantly lower expression in patients with a history of kidney disease. Furthermore, hsa_circ_0003028 and hsa_circ_0006990 showed higher expression in the tumor of participants with Lymphovascular/perineural invasion and oncocytoma type, respectively. Based on bioinformatic results, 15 circRNA-DEmiRNA-hub gene ceRNA regulatory axes were predicted, which included three hub genes, five miRNAs, and four selected circRNAs. In conclusion, the current work is the first to emphasize the expression of the hsa_circ_0020397, hsa_circ_0005986, hsa_circ_0003028, and hsa_circ_0006990 in RCC patients presents a novel perspective on the molecular processes underlying the pathogenic mechanisms of RCC.

Prostate and metastasis-directed focal therapy in prostate cancer: hype or hope?

INTRODUCTION

The paradigm of focal therapy's role in metastatic patients is being challenged by evolving attitudes and emerging data. At the current time, specifically regarding prostate cancer, does the evidence indicate this is more hype or hope?

AREAS COVERED

We searched the literature via PubMed, MEDLINE, and Embase for studies from 2014 to the present addressing focal therapy with non-palliative intent in metastatic prostate cancer patients, emphasizing prospective trials when available. We sought to address all common clinical scenarios: de novo synchronous diagnosis, oligorecurrence, oligoprogression, and mCRPC disease.

EXPERT OPINION

Current evidence is strongest, and in our opinion practice-changing, for prostate-directed RT in de novo metastatic patients with low metastatic burden. Metastasis-directed therapy with SBRT is consistently shown to have low rates of toxicity, and promising rates of ADT-free survival and progression-free survival. These can be utilized on a patient-by-patient basis with these endpoints in mind, but do not yet show sufficient benefit to be standard of care. This is a rich area of ongoing research, and many trials should publish in the coming years to shed light on many unanswered questions, including the role of cytoreductive prostatectomy, systemic therapy combined with MDT, and the integration of modern PET imaging.

Adjuvant Therapy for High-Risk Localized Renal Cell Carcinoma: Current Landscape and Future Direction

Locally and regionally advanced renal cell carcinoma (RCC) can recur at high rates even after visually complete resection of primary disease. Both targeted therapies and immunotherapies represent potential agents that might help reduce recurrence of RCC in these patients. This paper reviews the current body of evidence defining their potential impact and examines the large Phase III randomized clinical trials that have been performed to assess the safety and efficacy of these systemic therapies in the adjuvant setting. Given that the findings from these trials have been predominantly negative, this paper also explores the role of other potential adjuvant agents, including single and combination agent targeted therapies and immunotherapies, whose use is currently limited to metastatic RCC. Finally, the use of radiation therapy and the use of advanced imaging modalities in RCC are also considered.

Up-regulated PIF1 predicts poor clinical outcomes and correlates with low immune infiltrates in clear cell renal cell carcinoma

Background: Petite Integration Factor 1 (PIF1) is a multifunctional helicase and DNA processing enzyme that plays an important role in the process of several cancer types. However, the relationship between clear cell renal cell carcinoma (ccRCC) and PIF1 remains unclear. This study aims to explore the role of PIF1 in ccRCC tumorigenesis and prognosis. Methods: Based on The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) database, we retrieved and verified the expression of PIF1 in ccRCC tissues as well as normal tissues. To assess the protein expression of PIF1 by using the Human Protein Atlas and the Clinical Proteomic Tumor Analysis Consortium (CPTAC). We also performed receiver operating characteristic (ROC) curve analysis to differentiate the effectiveness of PIF1 in ccRCC and adjacent normal tissues. To evaluate the value of PIF1 on clinical outcomes in ccRCC patients by using multivariate methods and Kaplan‒Meier survival curves. Protein‒protein interaction (PPI) networks were made with STRING. We determined the relationship between the expression of PIF1 and immune cell infiltration with single-sample gene set enrichment analysis (ssGSEA). Results: Compared with normal tissues, the expression of PIF1 was significantly elevated in ccRCC. The mRNA expression of PIF1 is correlated with high TNM stage and high pathologic stage. The receiver operating characteristic (ROC) curve analysis showed that PIF1 was related to an area under the curve (AUC) value of 0.928 to distinguish between ccRCC tissues and normal tissues. Kaplan‒Meier survival analysis showed that the overall survival (OS) of ccRCC patients with a high level of PIF1 was significantly shorter than that of those with a low level of PIF1. PIF1 may play an important role in the occurrence of tumors. Correlation analysis showed that PIF1-mediated carcinogenesis may participate in the process of tumor immune escape in ccRCC. Conclusion: PIF1 could be a reference biomarker to identify ccRCC patients with poor prognosis. PIF1 may play a distinct role in the microenvironment of ccRCC by regulating tumor infiltration of immune cells, which is a new therapeutic target to affect the growth of the tumor.

Safety and Efficacy of Stereotactic Ablative Radiation Therapy for Renal Cell Cancer: 24-Month Results of the RSR1 Phase 1 Dose Escalation Study

PURPOSE

Stereotactic body radiation therapy (SBRT) has become a new therapeutic option for primary renal cell carcinoma. However, treatment doses lack consistency in the literature. The primary objective of this study was to determine the maximum tolerated dose for renal cancer SBRT.

METHODS AND MATERIALS

This phase 1 multicentric dose-escalation study assessed 4 dose levels: 8 Gy × 4, 8 Gy × 5, 10 Gy × 4, and 12 Gy × 4. The primary objective of this study was to determine the maximal tolerated dose, defined by the occurrence of dose-limiting toxicity was defined as any acute side effect of grade ≥4 based on the Common Terminology Criteria for Averse Events, version 4.0.

RESULTS

From October 2010 to September 2017, 13 patients were enrolled. The median follow-up was 23 months. There was no dose-limiting toxicity in our study, and the highest dose was reached successfully. No acute or late toxic effects above grade 2 were seen. There was no significant alteration of renal function after treatment. At 24 months, 2 patients had partial response and the others had stable disease.

CONCLUSIONS

After 24 months of follow-up, no dose-limiting toxicity was seen at any of the prescribed dose levels in our study. The findings suggest that our last dose level of 48 Gy in 4 12-Gy fractions can be considered safe and can be used in further studies.

CircNTNG1 inhibits renal cell carcinoma progression via HOXA5-mediated epigenetic silencing of Slug

BACKGROUND

Recent studies have identified that circular RNAs (circRNAs) have an important role in cancer via their well-recognized sponge effect on miRNAs, which regulates a large variety of cancer-related genes. However, only a few circRNAs have been well-studied in renal cell carcinoma (RCC) and their regulatory function remains largely elusive.

METHODS

Bioinformatics approaches were used to characterize the differentially expressed circRNAs in our own circRNA-sequencing dataset, as well as two public circRNA microarray datasets. CircNTNG1 (hsa_circ_0002286) was identified as a potential tumor-suppressing circRNA. Transwell assay and CCK-8 assay were used to assess phenotypic changes. RNA pull-down, luciferase reporter assays and FISH experiment were used to confirm the interactions among circNTNG1, miR-19b-3p, and HOXA5 mRNA. GSEA was performed to explore the downstream pathway regulated by HOXA5. Immunoblotting, chromatin immunoprecipitation, and methylated DNA immunoprecipitation were used to study the mechanism of HOXA5.

RESULTS

In all three circRNA datasets, circNTNG1, which was frequently deleted in RCC, showed significantly low expression in the tumor group. The basic properties of circNTNG1 were characterized, and phenotype studies also demonstrated the inhibitory effect of circNTNG1 on RCC cell aggressiveness. Clinically, circNTNG1 expression was associated with RCC stage and Fuhrman grade, and it also served as an independent predictive factor for both OS and RFS of RCC patients. Next, the sponge effect of circNTNG1 on miR-19b-3p and the inhibition of HOXA5 by miR-19b-3p were validated. GSEA analysis indicated that HOXA5 could inactivate the epithelial-mesenchymal transition (EMT) process, and this inactivation was mediated by HOXA5-induced SNAI2 (Slug) downregulation. Finally, it was confirmed that the Slug downregulation was caused by HOXA5, along with the DNA methyltransferase DNMT3A, binding to its promoter region and increasing the methylation level.

CONCLUSIONS

Based on the experimental data, in RCC, circNTNG1/miR-19b-3p/HOXA5 axis can regulate the epigenetic silencing of Slug, thus interfering EMT and metastasis of RCC. Together, our findings provide potential biomarkers and novel therapeutic targets for future study in RCC.

Stereotactic Body Radiotherapy for Localized Kidney Cancer

PURPOSE OF REVIEW

Stereotactic body radiation therapy (SBRT) is increasingly utilized in the management of localized kidney cancers, particularly for patients who are not surgical candidates. Herein, we provide a narrative review of SBRT in the management of localized kidney cancers.

RECENT FINDINGS

Recent prospective studies and multi-institutional retrospective studies highlight the safety and efficacy of SBRT in the management of renal tumors, a disease previously thought to be radioresistant. Studies have shown that local control is greater than 90% with rare grade 3 or 4 toxicity and no grade 5 toxicity. SBRT can be utilized successfully in the treatment of large kidney tumors (> 5 cm). New techniques such as MRI-guided radiation therapy may further improve the therapeutic ratio. However, randomized clinical trials are necessary to confirm the optimal dosing schedule and compare outcomes with nephrectomy, which remains the standard of care in suitable patients. Advances in SBRT have made this modality a safe and effective treatment option in the management of localized kidney cancers.

Bone metastasis risk and prognosis assessment models for kidney cancer based on machine learning

Background

Bone metastasis is a common adverse event in kidney cancer, often resulting in poor survival. However, tools for predicting KCBM and assessing survival after KCBM have not performed well.

Methods

The study uses machine learning to build models for assessing kidney cancer bone metastasis risk, prognosis, and performance evaluation. We selected 71,414 kidney cancer patients from SEER database between 2010 and 2016. Additionally, 963 patients with kidney cancer from an independent medical center were chosen to validate the performance. In the next step, eight different machine learning methods were applied to develop KCBM diagnosis and prognosis models while the risk factors were identified from univariate and multivariate logistic regression and the prognosis factors were analyzed through Kaplan-Meier survival curve and Cox proportional hazards regression. The performance of the models was compared with current models, including the logistic regression model and the AJCC TNM staging model, applying receiver operating characteristics, decision curve analysis, and the calculation of accuracy and sensitivity in both internal and independent external cohorts.

Results

Our prognosis model achieved an AUC of 0.8269 (95%CI: 0.8083-0.8425) in the internal validation cohort and 0.9123 (95%CI: 0.8979-0.9261) in the external validation cohort. In addition, we tested the performance of the extreme gradient boosting model through decision curve analysis curve, Precision-Recall curve, and Brier score and two models exhibited excellent performance.

Conclusion

Our developed models can accurately predict the risk and prognosis of KCBM and contribute to helping improve decision-making.

Sister Mary Joseph's Nodule From Renal Cell Carcinoma: A Case Report

Sister Mary Joseph’s nodules (SMJNs) are umbilical skin metastases of various abdominopelvic malignancies, and they rarely originate from renal cell carcinomas. Radiotherapy is typically used to treat the nodules as a palliative intention. We report a rare case of SMJN that originated from clear cell renal cell carcinoma, which was treated with external beam radiation therapy (EBRT) and interstitial brachytherapy (ISBT).

A 74-year-old male patient with a history of left renal cell carcinoma developed an umbilical nodule which was diagnosed as SMJN. The patient underwent EBRT (30 Gy in 10 fractions) and ISBT (12 Gy in two fractions), leading the nodule to complete resolution. This case report might support that radiotherapy, including ISBT, is effective for the treatment of SMJN from renal cell carcinoma.

A systematic review and meta-analysis on non-metastatic castration resistant prostate cancer: The radiation oncologist's perspective

Prostate cancer is the second most common cause of cancer-related mortality in men. In patients undergoing a failure after radical treatment, one of the therapeutic option is androgen deprivation: despite initial response rates, a progression to a state of castration resistance is observed in most of the patients. In the present article, we conducted a systematic review and meta-analysis of all clinical trials assessing treatment for nmCRPC with next-generation androgen receptor inhibitors. We performed a review and meta-analysis of phase III randomized controlled trials comparing new agents (apalutamide, enzalutamide, darolutamide) with placebo as control arm, in the setting of nmCRPC. Patients treated with next-generation ARIs had a 26% reduction in the risk of death compared with placebo; compared with other ARIs, darolutamide had the lowest rate of grade 3 and 4 AEs and the lowest therapy discontinuation rate due to any grade AEs. This meta-analysis shows that treatment with new ARIs is safe and significantly reduces the risk of death and of metastasis onset in nmCRPC patients. Under way studies on new biomarkers such as genomic classifiers will probably allow the stratification in more specific subsets of disease. New imaging modalities such as PSMA-PET have shown greater sensibility and specificity than conventional imaging in metastases detection. All patients were randomized in a 2:1 fashion, with a total of 2,694 who underwent next-generation ARIs (806 apalutamide, 955 darolutamide, 933 enzalutamide) and 1,423 in the placebo arm.

Biological Mechanisms to Reduce Radioresistance and Increase the Efficacy of Radiotherapy: State of the Art

Cancer treatment with ionizing radiation (IR) is a well-established and effective clinical method to fight different types of tumors and is a palliative treatment to cure metastatic stages. Approximately half of all cancer patients undergo radiotherapy (RT) according to clinical protocols that employ two types of ionizing radiation: sparsely IR (i.e., X-rays) and densely IR (i.e., protons). Most cancer cells irradiated with therapeutic doses exhibit radio-induced cytotoxicity in terms of cell proliferation arrest and cell death by apoptosis. Nevertheless, despite the more tailored advances in RT protocols in the last few years, several tumors show a relatively high percentage of RT failure and tumor relapse due to their radioresistance. To counteract this extremely complex phenomenon and improve clinical protocols, several factors associated with radioresistance, of both a molecular and cellular nature, must be considered. Tumor genetics/epigenetics, tumor microenvironment, tumor metabolism, and the presence of non-malignant cells (i.e., fibroblast-associated cancer cells, macrophage-associated cancer cells, tumor-infiltrating lymphocytes, endothelial cells, cancer stem cells) are the main factors important in determining the tumor response to IR. Here, we attempt to provide an overview of how such factors can be taken advantage of in clinical strategies targeting radioresistant tumors.

Sodium selenite inhibits proliferation and metastasis through ROS-mediated NF-κB signaling in renal cell carcinoma

Background

Sodium selenite (SSE) has been reported to exert anti-tumor effects in several cancer cells. However, the underlying mechanisms in renal cancer are yet to be elucidated. The effects of SSE on the proliferation, metastasis, and apoptosis of renal cancer cells, as well as its mechanism, were investigated in this study.

Methods

ACHN and 786-O renal cancer cells were treated with different concentrations of SSE, MTT, and colony formation assays were used to detect the proliferation ability of cells. The migration of cells was detected using scratch-wound-healing and transwell-migration assays. The effect of SSE on apoptosis was assessed by AnnexinV-FITC/PI double staining. Besides, Western blotting was employed to detect the protein-expression level and elucidate the underlying pathways. We also made subcutaneous xenografts in athymic mice to verify the effect of SSE on tumor growth in vivo.

Results

Our results demonstrated that treatment with SSE resulted in significant inhibition of cell proliferation and migration. Flow cytometry and Western blot confirmed that SSE induced apoptosis via the endogenous apoptotic pathway. We also confirmed that SSE treatment causes an increase in intracellular reactive oxygen species (ROS) levels, resulting in the inhibition of nuclear transcription factor-κB (NF-κB) signaling. Modulation of the ROS level by the chemical inhibitor N-acetyl-cysteine reversed the effect of SSE on cells. Similarly, subcutaneous xenografts in athymic mice models showed that SSE inhibits tumor growth in vivo.

Conclusion

These results indicate that SSE inhibits proliferation and migration and induces apoptosis via ROS mediated inhibition of NF-κB signaling in renal cancer cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09965-8.

Retroperitoneal Laparoscopic Radical Nephrectomy for Renal Cell Carcinoma: Indications and Long-term Outcome of a Cohort Study in Vietnam

OBJECTIVE: Laparoscopic radical nephrectomy (LRN) has been suggested as the standard care for cancer patients in the T1-2 stage. However, whether this advanced technique is most indicated suitable for renal tumors higher than T3a and N1 is unclear, especially in different regions and countries, such as the difference between European and Asia. METHODS: From 2013 to 2021, the data of pathologically diagnosed renal cell carcinoma (RCC) patients who received laparoscopic retroperitoneal radical nephrectomy was subjected to the present study. RESULTS: Overall, all the registered Vietnamese patients were eligible for the study. The average operative time was 86.8 ± 21.2 min and the percentage number of patients in stages 1, 2, and 3 were 134 (70.2%), 30 (15.7%), and 27 (14.1%), respectively. Patients in the 3rd stage had a significantly longer operative time than stages 1–2 (p = 0.0001). No Lymph-node dissection (LND) was recorded in 10 patients (5.2%), limited LND in 163 patients (85.3%), regional LND in 13 patients (6.8%), extended LND (eLND) in 5 patients (2.6%). eLND showed only prolongation of operative time (p = 0.000), however, did not increase intraoperative complications as well as prolonged the duration of analgesia and hospital stay when compared with the other 2 groups (p = 0.82, 0.85, 0.91). Mean follow-up time: 42.3 ± 24.7 months. The 5-year recurrent free survival and 5-year overall survival of the stage 1, 2, 3 were: 98.3%, 100%, 87.8%, and 98.9%, 100%, and 91.3%, respectively. (p = 0.0011, p = 0.0082). CONCLUSION: Retroperitoneal LRN could be an important technique in improving long-term oncological outcomes for Vietnamese patients, especially in the stage of T1-3N0-1M0 tumors. Radical retroperitoneal nephrectomy is safe and technically feasible as well as providing favorable long-term oncological outcomes for stage T1-2-3aN1M0 RCC.

Circular RNA circ-TNPO3 inhibits clear cell renal cell carcinoma metastasis by binding to IGF2BP2 and destabilizing SERPINH1 mRNA

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is a common malignant tumour of the urinary tract. The major causes of poor prognosis are the lack of early diagnosis and metastasis. Accumulating research reveals that circular RNAs (circRNAs) can play key roles in the development and the progression of cancer. However, the role of circRNAs in ccRCC is still uncertain.

METHODS

The circRNAs microarray (n = 4) was performed to investigate the circRNAs with differential expression in ccRCC tissues. The candidate circRNA was selected based on the cut-off criteria, such as circRNA expression abundance, circRNA size and the design of divergent primers. The circ-transportin-3 (TNPO3) levels in ccRCC tissues were tested by quantitative real-time (qRT)-PCR (n = 110). The characteristics and subcellular localization of circ-TNPO3 were identified via RNase R assay, qRT-PCR and fluorescence in situ hybridization (FISH). Then, we explored the biological roles of circ-TNPO3 in ccRCC via the function experiments in vitro and in vivo. RNA pull-down, RNA immunoprecipitation, bioinformatic analysis, RNA-FISH assays and rescue assays were applied to validate the interactions between circ-TNPO3, insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) and serpin family H member 1 (SERPINH1) to uncover the underlying molecular mechanisms of circ-TNPO3.

RESULTS

We detected the obvious downregulation of circ-TNPO3 in ccRCC compared to matched adjacent normal tissues (n = 110). The lower circ-TNPO3 expression was found in ccRCC patients with distant metastasis, higher World Health Organization/International Society of Urologic Pathologists (WHO/ISUP) grade and more advanced tumour T stage. In vitro and in vivo, circ-TNPO3 significantly suppressed the proliferation and migration of ccRCC cells. Mechanistically, we elucidated that circ-TNPO3 directly bound to IGF2BP2 protein and then destabilized SERPINH1 mRNA. Moreover, IGF2BP2/SERPINH1 axis was responsible for circ-TNPO3's function of inhibiting ccRCC metastasis. Epithelial splicing regulatory protein 1 (ESRP1) was probably involved in the biogenesis of circ-TNPO3.

CONCLUSIONS

Circ-TNPO3 can suppress ccRCC progression and metastasis via directly binding to IGF2BP2 protein and destabilizing SERPINH1 mRNA. Circ-TNPO3 may act as a potential target for ccRCC treatment.