Radiotherapy for renal-cell carcinoma

Role of main RNA modifications in cancer: N6-methyladenosine, 5-methylcytosine, and pseudouridine

Cancer is one of the major diseases threatening human life and health worldwide. Epigenetic modification refers to heritable changes in the genetic material without any changes in the nucleic acid sequence and results in heritable phenotypic changes. Epigenetic modifications regulate many biological processes, such as growth, aging, and various diseases, including cancer. With the advancement of next-generation sequencing technology, the role of RNA modifications in cancer progression has become increasingly prominent and is a hot spot in scientific research. This review studied several common RNA modifications, such as N⁶-methyladenosine, 5-methylcytosine, and pseudouridine. The deposition and roles of these modifications in coding and noncoding RNAs are summarized in detail. Based on the RNA modification background, this review summarized the expression, function, and underlying molecular mechanism of these modifications and their regulators in cancer and further discussed the role of some existing small-molecule inhibitors. More in-depth studies on RNA modification and cancer are needed to broaden the understanding of epigenetics and cancer diagnosis, treatment, and prognosis.

Phase II Trial of Stereotactic Ablative Radiation for Oligoprogressive Metastatic Kidney Cancer

BACKGROUND

Patients with metastatic renal cell carcinoma (mRCC) treated with systemic therapy sometimes progress at limited sites.The best treatment approach for patients with oligoprogression remains unclear.

OBJECTIVE

To determine the ability of stereotactic ablative radiation (SAbR) to extend ongoing systemic therapy in mRCC patients with oligoprogression.

DESIGN, SETTING, AND PARTICIPANTS

A single-arm phase II clinical trial was conducted at a university medical center and county hospital, including 20 patients with mRCC on first- to fourth-line systemic therapy with three or fewer sites of progression (including new sites) involving ≤30% of all sites.

INTERVENTION

SAbR to oligoprogressing metastases at outset and longitudinally, while radiated sites remain controlled and overall disease oligoprogressive.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary objective was to extend ongoing systemic therapy by >6 mo in >40% of patients. Secondary endpoints included overall survival, toxicity, and patient-reported quality of life.

RESULTS AND LIMITATIONS

Twenty patients were enrolled. Upfront and sequential SAbR was administered to a total of 37 sites. The local control rate was 100%. At a median follow-up of 10.4 mo (interquartile range: 5.8-16.4), SAbR extended the duration of the ongoing systemic therapy by >6 mo in 14 patients (70%, 95% confidence interval [CI]: 49.9-90.1). The median time from SAbR to the onset of new systemic therapy or death was 11.1 mo (95% CI: 4.5-19.3). The median duration of SAbR-aided systemic therapy was 24.4 mo (95% CI: 15.3-42.2). Median overall survival was not reached. One patient developed grade 3 gastrointestinal toxicity possibly related to treatment. There was no significant decline in quality of life. Limitations include nonrandomized design and a small patient cohort.

CONCLUSIONS

SAbR extended the duration of the ongoing systemic therapy for patients with oligoprogressive mRCC without undermining quality of life. These data support the evaluation of SAbR for oligoprogressive mRCC in a prospective randomized clinical trial.

PATIENT SUMMARY

Patients with metastatic kidney cancer on systemic therapy but progressing at limited sites may benefit from focused radiation to progressive sites. Focused radiation was safe and effective, and extended the duration of the ongoing systemic therapy.

A Web-Based Prediction Model for Cancer-Specific Survival of Middle-Aged Patients With Non-metastatic Renal Cell Carcinoma: A Population-Based Study

Background

Renal cell carcinoma (RCC) is one of the most common cancers in middle-aged patients. We aimed to establish a new nomogram for predicting cancer-specific survival (CSS) in middle-aged patients with non-metastatic renal cell carcinoma (nmRCC).

Methods

The clinicopathological information of all patients from 2010 to 2018 was downloaded from the SEER database. These patients were randomly assigned to the training set (70%) and validation set (30%). Univariate and multivariate COX regression analyses were used to identify independent risk factors for CSS in middle-aged patients with nmRCC in the training set. Based on these independent risk factors, a new nomogram was constructed to predict 1-, 3-, and 5-year CSS in middle-aged patients with nmRCC. Then, we used the consistency index (C-index), calibration curve, and area under receiver operating curve (AUC) to validate the accuracy and discrimination of the model. Decision curve analysis (DCA) was used to validate the clinical application value of the model.

Results

A total of 27,073 patients were included in the study. These patients were randomly divided into a training set (N = 18,990) and a validation set (N = 8,083). In the training set, univariate and multivariate Cox regression analysis indicated that age, sex, histological tumor grade, T stage, tumor size, and surgical method are independent risk factors for CSS of patients. A new nomogram was constructed to predict patients' 1-, 3-, and 5-year CSS. The C-index of the training set and validation set were 0.818 (95% CI: 0.802-0.834) and 0.802 (95% CI: 0.777-0.827), respectively. The 1 -, 3 -, and 5-year AUC for the training and validation set ranged from 77.7 to 80.0. The calibration curves of the training set and the validation set indicated that the predicted value is highly consistent with the actual observation value, indicating that the model has good accuracy. DCA also suggested that the model has potential clinical application value.

Conclusion

We found that independent risk factors for CSS in middle-aged patients with nmRCC were age, sex, histological tumor grade, T stage, tumor size, and surgery. We have constructed a new nomogram to predict the CSS of middle-aged patients with nmRCC. This model has good accuracy and reliability and can assist doctors and patients in clinical decision making.

Prognostic Impact of Baseline Neutrophil-to-Eosinophil Ratio in Patients With Metastatic Renal Cell Carcinoma Treated With Nivolumab Therapy in Second or Later Lines

Background

Inflammation is a crucial component in carcinogenesis. The neutrophil-to-eosinophil ratio (NER) has been studied as a biomarker of prognosis and predictive of response in metastatic renal cell carcinoma (mRCC). In the present study, we evaluated the relevance of baseline NER on the progression-free survival (PFS) and overall survival (OS) outcomes in real-world patients with mRCC treated with nivolumab in second or subsequent lines. We also assessed the association of baseline NER with objective response, as well as with toxicity and histology.

Methods

In this multicenter retrospective analysis of patients with mRCC treated with nivolumab, the last systemic absolute neutrophil and eosinophil count before treatment with nivolumab was used to calculate the NER. An additive Cox proportional hazards model was used to identify the cut-off point for NER considering PFS and the patients were allocated into low and high NER groups. Median OS and median PFS were estimated using the Kaplan-Meier estimator, and survival curves of groups were compared using the log-rank test. Univariable and multivariable Cox regression models were used to study OS and PFS and Fisher’s exact test was performed to evaluate the association of NER with the response, toxicity, and histology.

Results

The 49 analyzed patients had a median follow-up of nine months. The NER cut-off was established at 48, locating 29 patients in the low NER group (NER < 48) and 20 in the high NER group (NER ≥ 48). Median PFS and median OS were significantly shorter in patients with high NER versus low NER (3 vs. 30 months (p < 0.001) and 6 vs. 24 months (p = 0.002), respectively). Multivariable analyses showed that NER (HR 3.92 (95% CI: 1.66-9.23), p = 0.002) was an independent factor for PFS and that NER (HR 3.85 (95% CI: 1.33-11.17), p = 0.013) and progressive disease (HR 5.62 (95% CI: 1.88-16.83), p = 0.002) were independent factors for OS. NER was significantly associated with objective response rate (ORR) (NER ≥ 48-12.5% vs. NER < 48-87.5%, p = 0.003), immune-related adverse events (irAEs) (NER ≥ 48-10.0% vs. NER < 48-42.9%, p = 0.014), and tumor’s histology as patients of high NER group had more non-clear cell carcinoma than low NER group (35.0% vs. 7.4%, p = 0.017).

Conclusion

Our real-world data analysis of NER in patients with mRCC confirmed the prognostic value of this biomarker, supporting clinical utility in predicting survival. Results also suggested an association between lower NER and better ORR, and that irAEs occur more frequently in patients with a lower NER. However, further large-scale prospective studies are needed to confirm these findings and to validate this biomarker.

LINC02532 Contributes to Radiosensitivity in Clear Cell Renal Cell Carcinoma through the miR-654-5p/YY1 Axis

Background: Studies have shown that long non-coding RNAs (lncRNAs) play essential roles in tumor progression and can affect the response to radiotherapy, including in clear cell renal cell carcinoma (ccRCC). LINC02532 has been found to be upregulated in ccRCC. However, not much is known about this lncRNA. Hence, this study aimed to investigate the role of LINC02532 in ccRCC, especially in terms of radioresistance. Methods: Quantitative real-time PCR was used to detect the expression of LINC02532, miR-654-5p, and YY1 in ccRCC cells. Protein levels of YY1, cleaved PARP, and cleaved-Caspase-3 were detected by Western blotting. Cell survival fractions, viability, and apoptosis were determined by clonogenic survival assays, CCK-8 assays, and flow cytometry, respectively. The interplay among LINC02532, miR-654-5p, and YY1 was detected by chromatin immunoprecipitation and dual-luciferase reporter assays. In addition, in vivo xenograft models were established to investigate the effect of LINC02532 on ccRCC radioresistance in 10 nude mice. Results: LINC02532 was highly expressed in ccRCC cells and was upregulated in the cells after irradiation. Moreover, LINC02532 knockdown enhanced cell radiosensitivity both in vitro and in vivo. Furthermore, YY1 activated LINC02532 in ccRCC cells, and LINC02532 acted as a competing endogenous RNA that sponged miR-654-5p to regulate YY1 expression. Rescue experiments indicated that miR-654-5p overexpression or YY1 inhibition recovered ccRCC cell functions that had been previously impaired by LINC02532 overexpression. Conclusions: Our results revealed a positive feedback loop of LINC02532/miR-654-5p/YY1 in regulating the radiosensitivity of ccRCC, suggesting that LINC02532 might be a potential target for ccRCC radiotherapy. This study could serve as a foundation for further research on the role of LINC02532 in ccRCC and other cancers.

Palliative Radiation for Cancer Pain Management

Bone metastases are the most common cause of cancer-related pain. Radiation therapy (RT) is a very common and effective treatment to relieve pain. Conventionally fractionated RT typically consists of the following regimens: 8 Gy in a single treatment, 20 Gy in five fractions, 24 Gy in six fractions, or 30 Gy in ten fractions. All treatment regimens have similar rates of pain relief (range 50-80%), with single-fraction treatment often requiring retreatment. While many painful bony metastases can be managed with RT alone, some may be more complex, often requiring multidisciplinary management, including the need for surgical stabilization or augmentation prior to RT. There are multiple assessment tools including the neurologic, oncologic, mechanical, and systemic (NOMS) decision framework, which allows clinicians to assess the proper course of treatment for these patients. For patients with good prognosis, oligometastatic disease, or those presenting with more radioresistant tumors, stereotactic body radiotherapy (SBRT) may be another option, which offers ablative doses of radiation delivered over several treatments. This chapter reviews the fundamentals of RT for palliation.

Circular RNA FOXP1 Induced by ZNF263 Upregulates U2AF2 Expression to Accelerate Renal Cell Carcinoma Tumorigenesis and Warburg Effect through Sponging miR-423-5p

Renal cell carcinoma (RCC), as one of the most common malignant tumors in the urinary system, is featured with high morbidity and mortality. Although the improvement of clinical intervention, such as surgery technology, chemotherapy, and radiotherapy, has been made, the outcomes of RCC patients are still poor. Novel targets for RCC treatment are urgently needed. Recently, circRNA has been in-depth studied and is considered as a promising direction for gene target therapy. In this study, we explored the function of circFOXP1 in RCC progression and its underlying mechanisms. Firstly, we demonstrated the characterization and expression of circFOXP1 in RCC tissues and cells. Next, by conducting a serial experiment, we found that downregulated circFOXP1 inhibited cell proliferation, migration, invasion, and the Warburg effect. Next, our experiments found that circFOXP1 upregulated U2AF2 expression via sponging miR-423-5p in RCC cells. Moreover, we found that ZNF263 induced circFOXP1 expression in RCC cells. To sum up, our study partially demonstrated that the novel ZNF263/circFOXP1/miR-423-5p/U2AF2 axis has a role in RCC progression. Our results might provide a new direction for RCC therapeutic target exploring.

Immunotherapy and Radiation Therapy in Renal Cell Carcinoma

BACKGROUND

The management of renal cell carcinoma is rapidly evolving and immunotherapy, mostly consisting of immune checkpoint inhibitors, is revolutionizing the treatment scenario of metastatic patients. Novel fractionation schedules of radiotherapy, consisting of high doses in few fractions, can overcome the radioresistance of this tumor. Localized radiotherapy is associated with a systemic effect, known as the abscopal effect. This effect mediated by the immune system can be enhanced associating radiotherapy with immunotherapy.

OBJECTIVE

In this review, we explore the role of radiotherapy and immunotherapy in RCC, the rationale of combining these strategies and the on-going clinical trials investigating combinations of these two treatment modalities.

CONCLUSION

Combining immunotherapy and radiotherapy has a strong rationale and pre-clinical studies support their association because it can overcome the immunosuppression of the tumor microenvironment and increase the anti-tumor immune response. More clinical evidence, deriving from onclinical trials, are needed to prove the efficacy and safety of these treatments combined.

Eosinophil counts as a relevant prognostic marker for response to nivolumab in the management of renal cell carcinoma: a retrospective study

Background

Despite improvements in the management of renal cell carcinomas (RCC) with the advent of immunotherapy, only a few patients respond to these treatments. Predictors of response to nivolumab are currently being investigated but are still lacking.

Aim of the study

To evaluate eosinophil levels and their variations during treatment as an accurate biomarker for outcome in metastatic RCC treated with nivolumab.

Methods

A retrospective analysis was carried out for patients with metastatic RCC treated with nivolumab. Absolute eosinophil counts, their variation, and relative change were evaluated at six weeks. Relative eosinophil change was categorized in three groups (≥10%‐decrease, no change, ≥10%‐increase). Univariable and multivariable analyses were performed to determine whether eosinophils and their variations were prognostic markers for response at the first scan evaluation, progression‐free survival, and overall survival.

Results

Sixty‐five patients aged on average 66 years, 68% men, and 77% with good or intermediate International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk group were included. The median follow‐up was 16.6 months. Median overall survival (OS) was not reached for good prognosis and was 22.5 and 6.5 months for intermediate and poor prognosis, respectively. An increase in eosinophils and relative eosinophil change at six weeks of nivolumab was associated with a good response to immunotherapy (p = 0.012 and p = 0.024 respectively). In the group of patients with a 10%‐decrease in relative change, PFS reduced significantly compared to the other groups (p = 0.0044 with the 10%‐increase group and p = 0.03 with the no‐change group). This relative increase was independent of IMDC risks factors for better OS (HR = 3.3 [1.45–7.4]; p = 0.004). The eosinophil baseline level was not associated with response to treatment.

Conclusion

Eosinophil levels and relative eosinophil change at 6 weeks might be good prognostic markers for response to nivolumab for metastatic RCC, and were associated with better PFS and OS.

[Ultra-hypofractionated radiotherapy for the treatment of localized prostate cancer: Results, limits and prospects]

Still an emerging approach a few years ago, stereotactic body radiation therapy (SBRT) has ranked as a valid option for the treatment of localized prostate cancer. Inherent properties of prostatic adenocarcinoma (low α/β) make it the perfect candidate. We propose a critical review of the literature trying to put results into perspective to identify their strengths, limits and axes of development. Technically sophisticated, the stereotactic irradiation of the prostate is well tolerated. Despite the fact that median follow-up of published data is still limited, ultra-hypofractionated radiotherapy seems very efficient for the treatment of low and intermediate risk prostate cancers. Data seem satisfying for high-risk cancers as well. New developments are being studied with a main interest in treatment intensification for unfavorable intermediate risk and high-risk cancers. Advantage is taken of the sharp dose gradient of stereotactic radiotherapy to offer safe reirradiation to patients with local recurrence in a previously irradiated area.

Abscopal Effects of Local Radiotherapy Are Dependent on Tumor Immunogenicity

Although abscopal tumor regression remains a rare phenomenon, interest in exploiting how radiation stimulates the immune system to induce systemic abscopal response is increasing. Here, we tested the hypothesis that tumor immunogenicity determined the ability of radiotherapy to induce abscopal effects. We established highly (MC-38 and E.G7-OVA) or poorly (LL/2 and B16-F10) immunogenic tumor models in this study and treated them with sham radiation, a single dose of 15 Gy, or three fractions of 5 Gy on three consecutive days. Alterations in the tumor microenvironment after radiation were examined by flow cytometry and RNA sequencing. Our results demonstrated the positive correlation between tumor immunogenicity and the abscopal effect of radiotherapy. The single dose of 15 Gy radiation was an effective regimen for inducing abscopal effects in highly immunogenic tumors. Local radiation reshaped the tumor microenvironment of irradiated and non-irradiated distant tumors by increasing CD8 T-cell infiltration and reducing suppressive immune cell accumulation. However, radiation alone was insufficient to elicit abscopal effects in poorly immunogenic tumors. No significant alterations were detected in the non-irradiated distant tumor microenvironment after radiation of poorly immunogenic tumors. In addition, tumor immunogenic subtypes were associated with the radiological response and clinical outcome of patients receiving radiotherapy. These findings indicated that tumor immunogenicity was the dominant characteristic that could predict the abscopal effect of radiotherapy. Our study provides an in-depth understanding of the immunological mechanisms involved in abscopal effects and highlights the impact of tumor heterogeneity on the therapeutic efficacy of radiotherapy and their combination with immunotherapy in clinical trials.

Stereotactic Body Radiotherapy for Frail Patients with Primary Renal Cell Carcinoma: Preliminary Results after 4 Years of Experience

Simple Summary

Surgical therapy is currently the standard of care for the treatment of primary renal cell carcinoma (RCC). Alternative strategies such as stereotactic body radiotherapy (SBRT) have emerged as potentially curative treatment approaches. In this study, we show a promising short-term local control effect of SBRT in the management of primary RCC. The treatment was well tolerated with no high-grade side effects. The main advantages are the outpatient management without anesthesia and the non-invasive approach. Thus, SBRT appears to be a promising alternative to surgery, or ablative therapy, to treat primary RCC in patients with poor physical health. Future studies are needed to definitively assess the place of SBRT in the RCC treatment portfolio.

Abstract

Introduction: The aim of this study was to report the oncological outcomes and toxicity of stereotactic body radiotherapy (SBRT) to treat primary renal cell carcinoma (RCC) in frail patients unfit for surgery or standard alternative ablative therapies. Methods: We retrospectively enrolled 23 patients who had SBRT for primary, biopsy-proven RCC at our tertiary center between October 2016 and March 2020. Treatment-related toxicities were defined using CTCAE, version 4.0. The primary outcome was local control which was defined using the Response Evaluation Criteria in Solid Tumors. Results: The median age, Charlson score and tumor size were 81 (IQR 79–85) years, 7 (IQR 5–8) and 40 (IQR 28–48) mm, respectively. The most used dose fractionation schedule was 35 Gy (78.3%) in five or seven fractions. The median duration of follow-up for all living patients was 22 (IQR 10–39) months. Local recurrence-free survival, event-free survival, cancer-specific survival and overall survival were 96 (22/23), 74 (18/23), 96 (22/23) and 83% (19/23), respectively. There were no grade 3–4 side effects. No patients required dialysis during the study period. No treatment-related deaths or late complications were reported. Conclusion: SBRT appears to be a promising alternative to surgery or ablative therapy to treat primary RCC in frail patients.

Tumor microenvironment and radioresistance

Metastasis is not the result of a random event, as cancer cells can sustain and proliferate actively only in a suitable tissue microenvironment and then form metastases. Since Dr. Stephen Paget in the United Kingdom proposed the seed and soil hypothesis of cancer metastasis based on the analogy that plant seeds germinate and grow only in appropriate soil, considerable attention has focused on both extracellular environmental factors that affect the growth of cancer cells and the tissue structure that influences the microenvironment. Malignant tumor tissues consist of not only cancer cells but also a wide variety of other cells responsible for the inflammatory response, formation of blood vessels, immune response, and support of the tumor tissue architecture, forming a complex cellular society. It is also known that the amounts of oxygen and nutrients supplied to each cell differ depending on the distance from tumor blood vessels in tumor tissue. Here, we provide an overview of the tumor microenvironment and characteristics of tumor tissues, both of which affect the malignant phenotypes and radioresistance of cancer cells, focusing on the following keywords: diversity of oxygen and nutrient microenvironment in tumor tissue, inflammation, immunity, and tumor vasculature.

MITF Promotes Cell Growth, Migration and Invasion in Clear Cell Renal Cell Carcinoma by Activating the RhoA/YAP Signal Pathway

Microphthalmia-associated transcription factor (MITF) is a basic helix-loop-helix leucine zipper transcription factor involved in the lineage-specific regulation of melanocytes, osteoclasts and mast cells. MITF is also involved in the progression of melanomas and other carcinomas, including the liver, pancreas and lung. However, the role of MITF in clear cell renal cell carcinoma (ccRCC) is largely unknown. This study investigates the functional role of MITF in cancer and the molecular mechanism underlying disease progression in ccRCC. MITF knockdown inhibited cell proliferation and shifted the cell cycle in ccRCC cells. In addition, MITF knockdown reduced wound healing, cell migration and invasion compared with the controls. Conversely, MITF overexpression in SN12C and SNU482 cells increased cell migration and invasion. Overexpression of MITF activated the RhoA/YAP signaling pathway, which regulates cell proliferation and invasion, and increased YAP signaling promoted cell cycle-related protein expression. Additionally, tumor formation was impaired by MITF knockdown and enhanced by MITF overexpression in vivo. In summary, MITF expression was associated with aggressive tumor behavior, and increased the migratory and invasive capabilities of ccRCC cells. These effects were reversed by MITF suppression. These results suggest that MITF is a potential therapeutic target for the treatment of ccRCC.

Radiotherapy and Renal Cell Carcinoma: A Continuing Saga

Renal cell carcinoma (RCC) is one of the most aggressive malignancies of the genito-urinary tract, having a poor prognosis especially in patients with metastasis. Surgical resection remains the gold standard for localized renal cancer disease, with radiotherapy (RT) receiving much skepticism during the last decades. However, many studies have evaluated the role of RT, and although renal cancer is traditionally considered radio-resistant, technological advances in the RT field with regards to modern linear accelerators, as well as advanced RT techniques have resulted in breakthrough therapeutic outcomes. Additionally, the combination of RT with immune checkpoint inhibitors and targeted agents may maximize the clinical benefit. This review article focuses on the role of RT in the therapeutic management of renal cell carcinoma.

The Therapeutic Landscape of Renal Cell Carcinoma: From the Dark Age to the Golden Age

Oncologic treatments for renal cell carcinoma (RCC) have undergone a major revolution in the past 2 decades, moving away from the pre-2004 Dark Age during which interleukin 2 and interferon-α were the only therapeutic options and induced treatment responses in only 5% to 10% of patients with metastatic disease. The development of anti-angiogenic tyrosine kinase inhibitors against vascular endothelial growth factor receptor 2 and inhibitors of mammalian target of rapamycin complex 1 in 2005 introduced the Modern Age with better overall and progression-free survival and a greater number of patients (30%-40%) responding to and (∼80%) benefiting from these targeted therapeutic agents. The coming of age of the immuno-oncology era with the use of immune checkpoint inhibitors (ICIs) have ushered us into the Golden Age of metastatic RCC care, in which combined administrations of two ICIs (anti-programmed cell death protein 1/programmed death-ligand 1 and anti-cytotoxic T-lymphocyte-associated protein 4 or one tyrosine kinase inhibitor plus one ICI (anti-programmed cell death protein 1/programmed death-ligand 1) have recast the treatment landscape of clear cell RCC, the most common RCC subtype, with an approximately 60% response rate and an approximately 90% disease control rate that further improves metastatic RCC survival. Exciting clinical trials are in the pipeline investigating complementary/synergistic molecular mechanisms, based on studies investigating the biology, pathology, and genomics of renal carcinoma and the respective treatment outcome. This will enable us to enter the Diamond Age of precision medicine in which a specific treatment can be tailored to the specific biological and pathologic circumstance of an individual kidney tumor to offer more effective yet less toxic therapy.

Stereotactic Body Radiotherapy of a Solitary Metachronous Sphenoid Metastasis from Renal Cell Cancer: A Case Report

Nasosinus metastases from kidney cancer are an unusual clinical presentation although some cases are reported in the literature. Among these cases, sphenoidal metastases are even rarer. Here we report a case of lone sphenoid metastasis in patients with papillary renal cell cancer. Eight months after radical nephrectomy, the patient presented with progressively worsening diplopia. Magnetic resonance imaging showed a mass in the right sphenoid sinus. Histopathological examination of the biopsy sample confirmed diagnosis of sinonasal metastasis from papillary renal cell carcinoma. The patient was declined for surgical management and received stereotactic body radiation therapy. Reassessment MRI at 4 months showed a complete response of the treated sphenoid lesion.

The safety and efficacy of Cyberknife® for thymic malignancy

PURPOSE

To evaluate the safety and efficacy of Cyberknife® (CK) for the treatment of primary or recurring thymic tumours.

MATERIALS AND METHODS

We retrospectively reviewed 12 patients (16 tumour lesions) with primary or recurring thymic tumours who were treated with CK between March 2008 and October 2017. Their data was stored in prospectively collected database. Kaplan-Meier method was used to calculate survival curves.

RESULTS

Five patients (41.7%), who had inoperable disease or refused surgery, were treated with CK initially, and 7 patients (58.3%) were treated with CK when they had recurrence diseases. The disease sites treated with CK were primary tumour site (5), regional lymph nodes (4), tumour bed (3), chest wall (2), pleura (1), and bone (1). The median target volume was 43.8 cm³ (range, 13.1-302.5cm³) for the 16 tumour lesions. The median follow-up time was 69.3 months (range, 9.7-124.8 months). The median survival time was 48.2 months, and the 5-year and 10-year OS rates were 68.2% and 45.5%, respectively. A high response rate for the tumour lesions irradiated with CK was obtained. Only one patient (8%) experienced in-field recurrence, and the 5-year local recurrence free survival was 90.9%. A case indicated that CK may induce the abscopal effect, which provides the potential to combine CK and immunotherapy. No severe radiation related toxicities were observed, and no treatment related death occurred.

CONCLUSION

CK treatment resulted in good outcomes, particularly local control, with minimal side effects, in highly selected patients with primary and recurring thymic tumours. More studies with larger sample are needed.

Survival After Combining Stereotactic Body Radiation Therapy and Tyrosine Kinase Inhibitors in Patients With Metastatic Renal Cell Carcinoma

Background

Stereotactic body radiation therapy (SBRT) and tyrosine kinase inhibitors (TKIs) are effective treatments for metastatic renal cell carcinoma, but data on combining these two modalities are scarce. We aimed to investigate the survival outcomes of SBRT plus TKIs.

Methods

Data of patients treated with TKIs from December 2007 to June 2019 were collected. Patients received SBRT plus TKIs (TKI + SBRT group) or TKIs alone (TKI alone group). Local control (LC), time to change of systemic therapy (TTS), and overall survival (OS) were assessed.

Results

A total of 190 patients were included, and 85 patients received TKI + SBRT. The 2-year LC rate was 92.8%. The median OS in the TKI + SBRT group was significantly longer than that of the TKI alone group (63.2 vs 29.8 months; P < 0.001). In multivariate analysis, IMDC intermediate (HR 1.96; 95% CI 1.10-3.48; P = 0.022) and poor risk (HR 2.43; 95% CI 1.25-4.75; P = 0.009), oligometastasis (HR 0.41; 95% CI 0.26-0.65; P < 0.001), and the addition of SBRT (HR 0.48; 95% CI 0.31-0.75; P = 0.001) were prognostic factors for OS. Patients with oligometastasis (P = 0.009) and those with IMDC favorable (P = 0.044) or intermediate (P = 0.002) risk had significantly longer OS with TKI + SBRT. The median TTS were 21.5, 6.4, and 9.0 months in patients receiving SBRT before first-line TKI failure, SBRT after first-line TKI failure, and first-line TKI alone (P < 0.001). Five patients (5.9%) experienced SBRT-related grade 3 toxicities.

Conclusions

Combining SBRT with TKIs is tolerable and associated with longer OS in selected patients, such as those with oligometastasis and favorable or intermediate risk.

IFI16 Can Be Used as a Biomarker for Diagnosis of Renal Cell Carcinoma and Prediction of Patient Survival

The incidences of renal cell carcinoma (RCC) increase in number each year and account for about 2–3% of all malignant tumors. Many patients have metastasis by the time of diagnosis, and their prognosis is poor. Therefore, it is essential that new diagnostic and prognostic markers for kidney cancer are identified. In this study, we assessed the potential of IFI16 as a diagnostic and prognostic marker for RCC. We analyzed the TCGA and UALCAN databases and found IFI16 to be highly expressed in ccRCC. In addition, high IFI16 levels positively correlated with lymphatic metastasis, tumor stage, and histopathological grade. Kaplan-Meier curve analysis showed that IFI16 expression was related to the prognosis of patients, and high IFI16 expression indicated a worse overall survival (p = 5.1E–0.7). Receiver operating characteristic curve analysis showed that a combination of IFI16 expression and histopathological grade improved predictive accuracy (AUC = 0.697; 95%CI: 0.628–0.765, P < 0.001). Finally, the relative levels of IFI16 in ACHN and Caki-1 cells were higher than that of HK-2 cells by western blotting analysis and RT-PCR. Functional tests showed that knocking down IFI16 expression inhibited migration and invasion in vitro. Therefore, IFI16 is a potential biomarker for the diagnosis and prognosis of RCC patients.

Characteristics and Predictors of Radiographic Local Failure in Patients With Spinal Metastases Treated With Palliative Conventional Radiation Therapy

Purpose

Although local control is an important issue for longer-term survivors of spinal metastases treated with conventional external beam radiation therapy (EBRT), the literature on radiographic local failure (LF) in these patients is sparse. To inform clinical decision-making, we evaluated rates, consequences, and predictors of radiographic LF in patients with spinal metastases managed with palliative conventional EBRT alone.

Methods and Materials

We retrospectively reviewed 296 patients with spinal metastases who received palliative EBRT at a single institution (2006-2013). Radiographic LF was defined as radiologic progression within the treatment field, with death considered a competing risk. Kaplan-Meier, cumulative incidence, and Cox regression analyses determined overall survival estimates, LF rates, and predictors of LF, respectively.

Results

There were 182 patients with follow-up computed tomography or magnetic resonance imaging; median overall survival for these patients was 7.7 months. Patients received a median of 30 Gy in 10 fractions to a median of 4 vertebral bodies. Overall, 74 of 182 patients (40.7%) experienced LF. The 6-, 12-, and 18-month LF rates were 26.5%, 33.1%, and 36.5%, respectively, while corresponding rates of death were 24.3%, 38.1%, and 45.9%. Median time to LF was 3.8 months. Of those with LF, 51.4% had new compression fractures, 39.2% were admitted for pain control, and 35.1% received reirradiation; median time from radiation therapy (RT) to each of these events was 3.0, 5.7, and 9.2 months, respectively. Independent predictors of LF included single-fraction RT (8 Gy) (hazard ratio [HR], 2.592; 95% confidence interval [CI], 1.437-4.675; P = .002), lung histology (HR, 3.568; 95% CI, 1.532-8.309; P = .003), and kidney histology (HR, 4.937; 95% CI, 1.529-15.935; P = .008).

Conclusions

Patients experienced a >30% rate of radiographic LF by 1 year after EBRT. Single-fraction RT and lung or kidney histology predicted LF. Given the high rates of LF for patients with favorable prognosis, assessing the risk of death versus LF is important for clinical decision-making.

Stereotactic body radiotherapy (SBRT) in combination with drugs in metastatic kidney cancer: A systematic review

OBJECTIVE

To conduct a systematic review and meta-analysis of the role of SBRTdrug combination in patients affected by mRCC and associated oncologic outcomes and toxicity profiles.

EVIDENCE ACQUISITION

We performed a critical review of the Pubmed, Medline, and Embase databases from January 1, 2000 through April 30, 2020 according to the Preferred Reporting Items and Meta-Analyses statement. To assess the overall quality of the literature reviewed, we used a modified Delphi tool.

EVIDENCE SYNTHESIS

A total of 6 studies were included, corresponding to a cohort of 216 patients. Tyrosine Kinases Inhibitors were the most widely used drugs in combination with SBRT, being administered in 93% patients. No study reported an increase of radiation-induced toxicity.

CONCLUSIONS

SBRT resulted to be safe, without increase in terms of drugs-related adverse events in this setting. Moreover, this approach showed promising clinical outcomes in terms of LC and OS.

Circular RNA circSDHC serves as a sponge for miR-127-3p to promote the proliferation and metastasis of renal cell carcinoma via the CDKN3/E2F1 axis

BACKGROUND

There is increasing evidence that circular RNAs (circRNAs) have significant regulatory roles in cancer development and progression; however, the expression patterns and biological functions of circRNAs in renal cell carcinoma (RCC) remain largely elusive.

METHOD

Bioinformatics methods were applied to screen for circRNAs differentially expressed in RCC. Analysis of online circRNAs microarray datasets and our own patient cohort indicated that circSDHC (hsa_circ_0015004) had a potential oncogenic role in RCC. Subsequently, circSDHC expression was measured in RCC tissues and cell lines by qPCR assay, and the prognostic value of circSDHC evaluated. Further, a series of functional in vitro and in vivo experiments were conducted to assess the effects of circSDHC on RCC proliferation and metastasis. RNA pull-down assay, luciferase reporter and fluorescent in situ hybridization assays were used to confirm the interactions between circSDHC, miR-127-3p and its target genes.

RESULTS

Clinically, high circSDHC expression was correlated with advanced TNM stage and poor survival in patients with RCC. Further, circSDHC promoted tumor cell proliferation and invasion, both in vivo and in vitro. Analysis of the mechanism underlying the effects of circSDHC in RCC demonstrated that it binds competitively to miR-127-3p and prevents its suppression of a downstream gene, CDKN3, and the E2F1 pathway, thereby leading to RCC malignant progression. Furthermore, knockdown of circSDHC caused decreased CDKN3 expression and E2F1 pathway inhibition, which could be rescued by treatment with an miR-127-3p inhibitor.

CONCLUSION

Our data indicates, for the first time, an essential role for the circSDHC/miR-127-3p/CDKN3/E2F1 axis in RCC progression. Thus, circSDHC has potential to be a new therapeutic target in patients with RCC.

Expression of apolipoprotein C1 in clear cell renal cell carcinoma: An oncogenic gene and a prognostic marker

This study aimed to explore whether APOC1 expression has a function in the biological behavior of clear cell renal cell carcinoma (ccRCC) cells and its possible mechanism. Bioinformatics analysis of data TCGA and OnComine was conducted to explore the expression pattern and prognostic value of APOC1, as well as the relationship between APOC1 expression and clinical indicators. Loss- and gain- of APOC1 function assays were carried out to assess the biological functions of APOC1. Western blotting was applied to detect protein expression. We revealed that APOC1 was upregulated in ccRCC tissues. APOC1 expression was related to gender, grade, pathologic-T, pathologic-stage, and pathologic-M in patients with ccRCC. Meanwhile, Kaplan-Meier analysis evidenced that the high APOC1 expression indicated unfavorable outcomes of ccRCC. Functional experiments in vitro revealed that upregulation of APOC1 in UT33A cells promoted cell proliferation, invasion, and migration, while downregulation of APOC1 in 786-O cells had the opposite effect. Furthermore, epithelial mesenchymal transition (EMT) was activated in cells with upregulated APOC1 but inhibited in cells with down-regulated APOC1. Collectively, our data suggested that APOC1 was overexpressed in ccRCC cells and promoted the malignant biological behaviors and EMT of ccRCC cells.

The promising role of radiotherapy in the treatment of advanced or metastatic renal cell carcinoma: a narrative review

Traditionally, renal cell carcinoma (RCC) has been regarded to be “radioresistant”. Conventional fractionated radiation (CFRT) has played a limited role in RCC as a palliative treatment to relieve pain and bleeding. Succeed to the rapid development of precise radiotherapy techniques, realizing safe delivery of high-dose radiotherapy, an increasing amount of convincing data suggests that the delivery of high-dose-per-fraction radiation through stereotactic radiosurgery (SRS) or stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiotherapy (SABR) can help to overcome resistance to radiotherapy. Herein, we summarized and analyzed the data from randomized controlled trials, retrospective and prospective studies, and meta-analyses relating to the treatment of advanced and metastatic RCC (mRCC) with CFRT, SBRT, or SBRT combined with systemic therapy. CFRT has a limited effect on local control (LC) of advanced RCC and mRCC, but it is a major palliative treatment which could obviously relieve pain caused by cancer. SBRT and SRS have the significant advantage of being able to precisely deliver a high dose of radiation to the target tissues. SBRT could cause a higher LC for advanced and metastatic RCC and could be used as an alternative to surgery for patients with oligometastatic RCC. The combination of SBRT with systemic therapy, such as targeted therapy or immunotherapy, is safe and tolerable. Concurrent immunotherapy and SBRT is a promising treatment strategy for patients with advanced or metastatic RCC. However, research on radiotherapy combined with systemic therapy is still limited and further studies to explore this treatment for RCC are urgently needed.

Coupled Mass-Spectrometry-Based Lipidomics Machine Learning Approach for Early Detection of Clear Cell Renal Cell Carcinoma

A discovery-based lipid profiling study of serum samples from a cohort that included patients with clear cell renal cell carcinoma (ccRCC) stages I, II, III, and IV (n = 112) and controls (n = 52) was performed using ultraperformance liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry and machine learning techniques. Multivariate models based on support vector machines and the LASSO variable selection method yielded two discriminant lipid panels for ccRCC detection and early diagnosis. A 16-lipid panel allowed discriminating ccRCC patients from controls with 95.7% accuracy in a training set under cross-validation and 77.1% accuracy in an independent test set. A second model trained to discriminate early (I and II) from late (III and IV) stage ccRCC yielded a panel of 26 compounds that classified stage I patients from an independent test set with 82.1% accuracy. Thirteen species, including cholic acid, undecylenic acid, lauric acid, LPC(16:0/0:0), and PC(18:2/18:2), identified with level 1 exhibited significantly lower levels in samples from ccRCC patients compared to controls. Moreover, 3α-hydroxy-5α-androstan-17-one 3-sulfate, cis-5-dodecenoic acid, arachidonic acid, cis-13-docosenoic acid, PI(16:0/18:1), PC(16:0/18:2), and PC(O-16:0/20:4) contributed to discriminate early from late ccRCC stage patients. The results are auspicious for early ccRCC diagnosis after validation of the panels in larger and different cohorts.

Up-Regulation of miR-26a-5p Inhibits E2F7 to Regulate the Progression of Renal Carcinoma Cells

Background

Metastasis is the main cause of renal cell carcinoma (RCC) tumor death, and effective inhibition of RCC metastasis is an essential means to meliorate the prognosis of RCC patients. MicroRNAs (miRs) have been proved to be stable and important biomarkers for several malignancies. This study is therefore set out to explore the metastasis-related miR and its mechanism in RCC.

Methods

The expression of miR- 26a -5p in RCC was analyzed using the expression profile in the Cancer Genome Atlas (TCGA). MiR-26a-5p and E2F transcription factor 7 (E2F7) in RCC patients were detected by qRT-PCR. Cell Counting Kit-8 (CCK-8) was adopted to assess cell proliferation, Transwell was utilized to evaluate migration and invasion, and flow cytometry (FC) was used to determine apoptosis. Mouse cell-derived and patient-derived xenotransplantation models were established to evaluate the effect of miR-26a-5p on tumor growth and metastasis in vivo. The molecular mechanism of miR-26a-5p was analyzed by dual-luciferase reporter (DLR) gene analysis, qRT-PCR, and Western blot (WB) both in vivo and in vitro.

Results

MiR-26a-5p was reduced in renal carcinoma cells and may serve as a biomarker for renal cancer metastasis and prognosis. MiR-26a-5p up-regulation inhibited migration and invasion in renal cell lines and tumor metastasis in vivo. Bioinformatics target prediction and RNA-seq results showed that E2F7 was among the targets of miR-26a-5p and was significantly inhibited by miR-26a-5p in vivo and in vitro.

Conclusion

MiR-26a-5p presents low expression in RCC and promotes RCC cell apoptosis and prevents cells from proliferating and invading by targeting E2F7, which is a promising therapeutic target for RCC.

Intradural extramedullary spinal metastasis of renal cell carcinoma: illustrative case report and comprehensive review of the literature

STUDY DESIGN

Literature review.

OBJECTIVES

Intradural metastasis of renal cell carcinoma (RCC) has rarely been reported. We describe a case of an intradural extramedullary spinal metastasis to the cervical spine in a 68-year-old male treated for RCC 22 years prior. Additionally, we review the known reports of both intradural extramedullary and intramedullary of RCC.

METHODS

Case report and literature review.

RESULTS

A 68-year-old male with a history of right-sided nephrectomy for RCC preformed 22 years prior now presents with a MRI of the cervical spine showing a 1.5 cm contrast enhancing intradural extramedullary lesion at the level of C3-C4. Surgical resection of the lesion was performed. The tumor's histological and immunohistochemical profile was consistent with metastatic RCC. There are 18 reported cases of intradural extramedullary metastases of sporadic RCC. The average age at diagnosis was 61.6 ± 14.3 years. The interval from diagnosis of primary RCC to diagnosis metastasis ranged from 0 to 264 months (mean 46.8 ± 74.0 months). Sixteen cases of intramedullary renal cell carcinoma metastasis are reported. The average age at time of diagnosis was 53.6 ± 10.2 years. The interval from diagnosis of primary RCC to diagnosis of metastasis ranged from 0 to 180 months (mean 20.9 ± 53.4 months).

CONCLUSION

The 22-year interval from diagnosis of primary RCC to intradural metastasis is the longest latency reported in the literature. Intramedullary metastases tend to have a younger age at diagnosis and shorter interval from diagnosis of primary RCC compared to extramedullary lesions.

Low doses of ionizing radiation activate endothelial cells and induce angiogenesis in peritumoral tissues

PURPOSE

During radiotherapy the peritumoral tissues are daily exposed to subtherapeutic doses of ionizing radiation. Herein, the biological and molecular effects of doses lower than 0.8 Gy per fraction (LDIR), previously described as angiogenesis inducers, were assessed in human peritumoral tissues.

MATERIAL AND METHODS

Paired biopsies of preperitoneal adipose tissue were surgically collected from 16 patients diagnosed with locally advanced rectal cancer who underwent neo-adjuvant radiotherapy. One of the biopsies is located in the vicinity of the region where the tumor received the prescribed dose of radiation, and thus exposed to LDIR; the other specimen, outside all beam apertures, was used as an internal calibrator (IC). Microvessel density (MDV) was quantified by immunohistochemistry and the expression of angiogenic, pro-inflammatory, adhesion and oxidative stress genes was assessed by quantitative RT-PCR using exclusively endothelial cells (ECs) isolated by laser capture microdissection microscopy.

RESULTS

LDIR activated peritumoral ECs by significantly up-regulating the expression of several pro-angiogenic genes such as VEGFR1, VEGFR2, ANGPT2, TGFB2, VWF, FGF2, HGF and PDGFC and down-regulating the pro-inflammatory IL8 marker. Accordingly, the MVD was significantly increased in peritumoral tissues exposed to LDIR, compared to the IC. The patients that yielded a larger pro-angiogenic response, also showed the highest MVD.

CONCLUSIONS

LDIR activate ECs in peritumoral tissues that are associated with increased MVD. Although the technological advances in radiotherapy have contributed to reduce the damage to healthy tissues over the past years, the anatomical regions receiving LDIR should be taken into account in the treatment plan report for patient follow-up and in future studies to correlate these doses with tumor dissemination.

Combination of High Dose Hypofractionated Radiotherapy with Anti-PD1 Single Dose Immunotherapy Leads to a Th1 Immune Activation Resulting in a Complete Clinical Response in a Melanoma Patient

The development of immunotherapy has recently modified the anti-tumor therapeutic arsenal; particularly, immune checkpoint inhibitors have led to a significant increase in overall survival. The current challenge is now to select good responder patients by identifying early biomarkers to propose therapeutic combinations that potentiate the efficacy of the therapy. Here we report the case of a 60-year-old man with superficial melanoma treated with high-dose hypo fractionated radiotherapy (H-SRT) combined with a single dose of anti-PD1 immunotherapy (Nivolumab) for a metastatic lymph node recurrence due to cancer progression. In this study, we present the results obtained regarding the activation of the Th1 immune response after H-SRT treatment followed by anti PD-1 therapeutic protocol. These results were correlated with clinical data to identify potential immunological biomarkers of treatment efficacy. This exceptional case report shows that a combination of H-SRT with a single dose of anti-PD1 immunotherapy may allow a better activation of the immune response in favor of a complete clinical response.

Pushing the limits of metastasis-directed treatment in metastatic renal cell carcinoma in the era of targeted therapy

OBJECTIVE

To assess the role of metastasis directed therapy and in particular surgical metastasectomy (MxT) in metastatic renal cell carcinoma (mRCC) in the era of targeted therapy.

METHOD

The files of all patients who underwent MxT for treatment of mRCC in University Hospitals Leuven between 1989 and 2015 were reviewed.

RESULTS

One hundred and thirty eight patients met the inclusion criteria. Mean age at MxT was 59.3 (IQR: 57.5-61.0) years. Median follow-up was 50.1 (42.3-63.8) months. Due to adequate patient selection, 91.9% of MxT achieved no evidence of disease status, which resulted in long median overall survival of 87.8 (63.8-113.4) months and median cancer specific survival of 92.8 (69.5-123.4) months. On multivariate analysis, primary tumor stage >pT2 (hazard ratio [HR] 2.79 [1.47-5.28] P= 0.002), unreached no evidence of disease status (HR 8.62 [3.19-23.32] P< 0.001), presence of nonpulmonary metastasis (HR 2.29 [1.02-5.10] P= 0.0449) and sarcomatoid dedifferentiation in the primary tumor (HR 4.52 [1.15-17.69] P= 0.03) significantly impacted overall survival. Survival did not differ for MxT performed before and after the advent of vascular endothelial growth factor receptor-tyrosine kinase inhibitors.

DISCUSSION

Our study confirms the validity of MxT in mRCC in the tyrosine kinase inhibitors era. MxT should be considered in mRCC whenever the patient is fit enough to undergo surgery and complete removal of metastasis is considered possible, independent of number, location, and chronology of appearance of metastasis. Patients with pulmonary metastasis only, seem to be the best candidates for surgical MxT.

Possible abscopal effect after discontinuation of nivolumab in metastatic renal cell carcinoma

INTRODUCTION

Renal cell carcinoma has been considered radioresistant. Recently, several studies have reported the efficacy of combination therapy using radiotherapy and immune checkpoint inhibitors.

CASE PRESENTATION

In 1999, a 56-year-old woman underwent left nephrectomy (clear cell carcinoma, pT1bN0M0). Seventeen years postoperatively, recurrence in the left lung hilum was observed. Despite administration of three molecular target drugs, all treatments were terminated due to adverse events. Nivolumab was initiated in December 2016. In August 2017, subcutaneous and lung metastases were observed. Moreover in January 2018, right renal metastasis was noted. After 22 cycles of nivolumab treatment, metastasis in the iliac bone was observed, and the patient was subjected to conventional palliative external beam radiation therapy. Five months after radiotherapy, there was significant reduction in multiple metastases. Here, we reported the case presenting with possible abscopal effect.

CONCLUSION

Radiotherapy combined with immune checkpoint inhibitors may induce systemic effects against metastatic renal carcinoma.

Identification of small molecule drugs and development of a novel autophagy-related prognostic signature for kidney renal clear cell carcinoma

Abnormal autophagic levels have been implicated in the pathogenesis of multiple cancers, however, its role in tumors is complex and has not yet been explored clearly. Hence, we aimed to explore the prognostic values of autophagy-related genes (ARGs) for kidney renal clear cell carcinoma (KIRC). Differentially expressed ARGs and transcription factors (TFs) were identified in KIRC patients obtaining from the The Cancer Genome Atlas (TCGA) database. Then, networks between TFs and ARGs, gene ontology functional annotations and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were conducted. Next, we performed consensus clustering, COX regression analysis and Lasso regression analysis to identify the prognostic ARGs. Finally, an individual prognostic index (PI, riskScore) was established. Based on TCGA cohort and ArrayExpress cohort, Survival analysis, ROC curve, independent prognostic analysis, and clinical correlation analysis were also performed to evaluate this PI. Based on differentially expressed ARGs, KIRC patients were successfully divided into two clusters (P = 5.916e-04). AS for PI, it was constructed based on 11 ARGs and significantly classified KIRC patients into high-risk group and low-risk group in terms of OS (P = 4.885e-15 for TCGA cohort, P = 6.366e-03 for ArrayExpress cohort). AUC of its ROC curve reached 0.747 for TCGA cohort and 0.779 for ArrayExpress cohort. What's more, this PI was proven to be a valuable independent prognostic factor in both univariate and multivariate COX regression analysis (P < .001). Prognostic nomograms were also performed to visualize the relationship between individual predictors and survival rates in patients with KIRC. By means of connectivity map database, emetine, cephaeline and co-dergocrine mesilate related to ARGs were found to be negatively correlated with KIRC. This study provided an effective PI for KIRC and also displayed networks between TFs and ARGs. KIRC patients were successfully divided into two clusters based on differentially expressed ARGs. Besides, small molecule drugs related to ARGs were also identified for KIRC.

Advances in Radiobiology of Stereotactic Ablative Radiotherapy

Radiotherapy (RT) has been developed with remarkable technological advances in recent years. The accuracy of RT is dramatically improved and accordingly high dose radiation of the tumors could be precisely projected. Stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT), also known as stereotactic ablative radiotherapy (SABR), are rapidly becoming the accepted practice in treating solid small sized tumors. Compared with the conventional fractionation external beam radiotherapy (EBRT), SABR with very high dose per fraction and hypo-fractionated irradiation yields convincing and satisfied therapeutic effects with low toxicity, since tumor cells could be directly ablated like radiofrequency ablation (RFA). The impressive clinical efficacy of SABR is greater than expected by the linear quadratic model and the conventional radiobiological principles, i.e., 4 Rs of radiobiology (reoxygenation, repair, redistribution, and repopulation), which may no longer be suitable for the explanation of SABR's ablation effects. Based on 4 Rs of radiobiology, 5 Rs of radiobiology emphasizes the intrinsic radiosensitivity of tumor cells, which may correlate with the responsiveness of SABR. Meanwhile, SABR induced the radiobiological alteration including vascular endothelial injury and the immune activation, which has been indicated by literature reported to play a crucial role in tumor control. However, a comprehensive review involving these advances in SABR is lacking. In this review, advances in radiobiology of SABR including the role of the 4 Rs of radiobiology and potential radiobiological factors for SABR will be comprehensively reviewed and discussed.

Abscopal effect after hypofractionated radiotherapy in metastatic renal cell carcinoma pretreated with pazopanib

Background: The abscopal effect consists of distant metastases response after local treatment based on systemic immune stimulation. It is a rare event observed in many tumors, especially with radiotherapy and immunotherapy. Clinical case: We report the long-term abscopal effect in a metastatic renal cell carcinoma patient with lung metastasectomy, after hypofractionated radiotherapy on lymph node metastasis. The patient was pretreated with pazopanib, which was discontinued early owing to toxicity before radiotherapy. Methodology: Immunohistological analyses of the primary tumor and metastases were performed. Discussion: We supposed that radiotherapy, and maybe tyrosine kinase inhibitors, could act as immune-primers for abscopal effect modifying the immune tumor microenvironment. Conclusion: Future studies are needed to optimize the combination of radiotherapy with systemic therapy for better long-term tumor control in selected patients.

Intramedullary craniovertebral junction metastasis leading to the diagnosis of underlying renal cell carcinoma

Background:

Intramedullary spinal cord metastases represent 4–8.5% of the central nervous system metastases and affect only 0.1–0.4% of all patients. Those originating from renal cell carcinoma (RCC) are extremely rare. Of the eight patients described in the literature with metastatic RCC and intramedullary cord lesion, only five were found in the cervical spine. Here, the authors add a 6^th case involving an RCC intramedullary metastasis at the C1–C2 level.

Case Description:

A 78-year-old male patient presented with intermittent cervicalgia of 5 months duration accompanied by few weeks of a progressive severe right hemiparesis, up to hemiplegia. The magnetic resonance imaging (MRI) examination revealed an intramedullary expansive lesion measuring 10 mm×15 mm at the C1–C2 level; it readily enhanced with contrast. A total body computed tomography (CT) scan documented an 85 mm mass involving the right kidney, extending to the ipsilateral adrenal gland, and posteriorly infiltrating the ipsilateral psoas muscle. The subsequent CT-guided fine-needle biopsy confirmed the diagnosis of an RCC (Stage IV). The patient next underwent total surgical total removal of the C1–C2 intramedullary mass, following which he exhibited a slight motor improvement, with the right hemiparesis (2/5). He died after 14 months due to global RCC tumor progression.

Conclusion:

The present case highlights that a patient without a prior known diagnosis of RCC may present with an intramedullary C1–C2 metastasis. In such cases, global staging is critical to determine whether primary lesion resection versus excision of metastases (e.g., in this case, the C1–C2 intramedullary tumor) are warranted.

Management of oligometastatic and oligoprogressive renal cell carcinoma: state of the art and future directions

INTRODUCTION

The aim of this paper was to perform a narrative review of the literature on the available approaches in the treatment of two emerging subpopulations of metastatic renal cell carcinoma (mRCC) patients: the oligometastatic disease (less than 5 metastasis) and the oligoprogressive disease, defined as worsening in maximum 3-5 sites while all other tumor sites are controlled by systemic therapy.

AREAS COVERED

We explore all possible approaches in these settings of patients: the role of local therapies, considering both surgical metastasectomy and/or ablative techniques, the efficacy of systemic therapies and the rationale behind active surveillance. We also discuss ongoing clinical trials in these settings.

EXPERT OPINION

Two different strategies are emerging as the most promising for the approach to the oligometastatic/oligoprogressive mRCC patient: (1) the use of immunocheckpoint inhibitors following metastasectomy; (2) the use of stereotactic radiotherapy alone or combined with immunotherapy for oligometastatic disease. The lack of validated biomarkers of response in these mRCC patient subpopulations is opening the way to the employment of novel technologies. Among them, the use of artificial intelligence seems to be the candidate to contribute to precision oncology in patients with mRCC.

miR-429-CRKL axis regulates clear cell renal cell carcinoma malignant progression through SOS1/MEK/ERK/MMP2/MMP9 pathway

The pathogenesis and tumorigenesis of clear cell renal cell carcinoma (ccRCC) remain unclear. The deregulations of miR-429, a member of miR-200 family, and v-crk sarcoma virus CT10 oncogene homologue (avian)-like (CRKL), an adaptor protein of CRK family, are involved in the development, metastasis and prognosis of various cancers. Current study aimed to demonstrate the differential expressions of miR-429 and CRKL with their correlationship and molecular regulation mechanism in ccRCC malignancy. miR-429 and CRKL separately showed suppressing and promoting effects in ccRCC. Lower miR-429 expression and higher CRKL expression were negatively correlated in surgical cancerous tissues by promoting the advance of ccRCC. By binding to the 3'-UTR of CRKL, miR-429 reversely regulated CRKL for its functionalities in ccRCC cells. CRKL knockdown and overexpression separately decreased and increased the in vitro migration and invasion of 786-O cells, which were consistent with the influences of miR-429 overexpression and knockdown on 786-O through respectively downregulating and upregulating CRKL via SOS1/MEK/ERK/MMP2/MMP9 pathway. The enhancements of CRKL expression, migration and invasion abilities and SOS1/MEK/ ERK/MMP2/MMP9 activation induced by TGF-β stimulation in 786-O cells could be antagonized by miR-429 overexpression. Exogenous re-expression of CRKL abrogated miR-429 suppression on the migration and invasion of 786-O cells. Collectively, miR-429 deficiency negatively correlated with CRKL overexpression promoted the aggressiveness of cancer cells and advanced the clinical progression of ccRCC patients. miR-429-CRKL axial regulation provides new clues to the fundamental research, diagnosis and treatment of ccRCC.

Metastasis-directed therapy for oligometastatic urological tumours: still no second-hand news

For patients presenting with limited metastatic disease burden, known as the oligometastatic state of disease, a more aggressive treatment approach targeting the new or progressive metastatic lesions might improve patient outcome, with no or only limited toxicity to be expected from the treatment. This review provides an overview of the existing evidence and on-going trials on oligometastatic disease and metastasis-directed therapy in the field of renal, bladder and prostate cancer.

Survival Outcomes After Adding Stereotactic Body Radiotherapy to Metastatic Renal Cell Carcinoma Patients Treated With Tyrosine Kinase Inhibitors

OBJECTIVE

Long-lasting control is rarely achieved with tyrosine kinase inhibitors (TKI) alone in metastatic renal cell carcinoma (mRCC). Our study aimed to investigate the survival outcomes of adding stereotactic body radiotherapy (SBRT) to TKI in mRCC.

MATERIALS AND METHODS

From September 2015 to September 2018, 56 patients treated with TKI received SBRT for 103 unresectable lesions. A total of 24 and 32 patients were irradiated before and after TKI failure, respectively. Overall survival (OS) was calculated from metastases. Progression-free survival (PFS) was calculated from SBRT.

RESULTS

Overall, 10, 32, and 12 patients had International Metastatic Renal Cell Carcinoma Database Consortium favorable, intermediate, and poor risk. Median follow-up was 21.7 months (range, 5.1 to 110.6 mo). Median OS was 61.2 months. The median PFS was 11.5 months, while the 2-year LC rate was 94%. Sixteen (34%) lesions achieved complete response (CR) in patients irradiated before TKI failure, whereas only 4 (7%) lesions yielded CR in those irradiated after TKI failure (P=0.001). The median PFS in CR group was significantly longer than that of non-CR group (18.9 vs. 7.1 mo; P=0.003). The 5-year OS in CR group was 86%, compared with 48% in non-CR group (P=0.010). Four (7%) patients experienced Grade 3 toxicity.

CONCLUSIONS

Adding SBRT to TKI is safe and seems to improve survival in mRCC. Patients irradiated before TKI failure have higher CR rate, and the favorable local response might turn into survival benefit.

GRIM-19 deficiency promotes clear cell renal cell carcinoma progression and is associated with high TNM stage and Fuhrman grade

Clear cell renal cell carcinoma (ccRCC) exhibits the highest mortality among all urological malignancies. The investigation of the potential disease progression markers can improve ccRCC diagnosis and treatment. Gene associated with retinoid-interferon-induced mortality-19 (GRIM-19) is involved in carcinogenesis and cancer progression in a variety of cancer types including RCC. While, its role in ccRCC remains unclear, this cancer type is considered the most aggressive RCC subtype. In the present study, RT-qPCR, western blotting and immunohistochemical (IHC) assays demonstrated that GRIM-19 protein and mRNA levels were downregulated in ccRCC tumor tissues compared with the corresponding levels noted in paracancerous non-tumor tissues. The deficiency of this protein contributed in relaxed and/or collapsed structures of the kidney tubules and collecting duct noted in tumor tissues. Moreover, the reduction in GRIM-19 expression was associated with high tumor, lymph nodes and metastasis (TNM) stage and Fuhrman grade of ccRCC tumors. The data suggested that GRIM-19 acted as a tumor suppressor and that its deficiency promoted ccRCC development and progression. GRIM-19 can be considered a potential tumor marker for ccRCC.

Differential regulation of microRNA-15a by radiation affects angiogenesis and tumor growth via modulation of acid sphingomyelinase

Activation of acid sphingomyelinase (SMPD1) and the generation of ceramide is a critical regulator of apoptosis in response to cellular stress including radiation. Endothelial SMPD1 has been shown to regulate tumor responses to radiation therapy. We show here that the SMPD1 gene is regulated by a microRNA (miR), miR-15a, in endothelial cells (ECs). Standard low dose radiation (2 Gy) upregulates miR-15a and decreases SMPD1 levels. In contrast, high dose radiation (10 Gy and above) decreases miR-15a and increases SMPD1. Ectopic expression of miR-15a decreases both mRNA and protein levels of SMPD1. Mimicking the effects of high dose radiation with a miR-15a inhibitor decreases cell proliferation and increases active Caspase-3 & 7. Mechanistically, inhibition of miR-15a increases inflammatory cytokines, activates caspase-1 inflammasome and increases Gasdermin D, an effector of pyroptosis. Importantly, both systemic and vascular-targeted delivery of miR-15a inhibitor decreases angiogenesis and tumor growth in a CT26 murine colorectal carcinoma model. Taken together, our findings highlight a novel role for miR mediated regulation of SMPD1 during radiation responses and establish proof-of-concept that this pathway can be targeted with a miR inhibitor.

TNFAIP8 promotes the migration of clear cell renal cell carcinoma by regulating the EMT

Background: Clear cell renal cell carcinoma (ccRCC) is characterized by high metastatic potential, and the epithelial-mesenchymal transition (EMT) has been shown to play a key role in multiple cancer progression, migration and metastasis and is the leading cause of poor prognosis. Currently, tumor necrosis factor-α-induced protein 8 (TNFAIP8/TIPE) is a newly discovered tumorigenesis factor, and TNFAIP8 and the EMT influence the migration of renal cancer cells.

Methods: In this study, we first analyzed the relationship between TNFAIP8 and ccRCC using bioinformatics, followed by immunohistochemistry to evaluate the relationship between the two in clinical samples. Subsequently, reverse transcription PCR and western blotting confirmed the expression of TNFAIP8 in ccRCC cells. Furthermore, we measured the migration and invasion abilities by using wound healing and transwell assays after overexpression or knockdown of TNFAIP8 in cells. In addition, we verified whether TNFAIP8 affects the EMT process in ccRCC by quantitative real-time PCR, western blotting, immunohistochemistry and immunofluorescence experiments.

Results: Through database analysis, we found that TNFAIP8 was highly expressed in ccRCC patients and was positively correlated with tumor stage and grade, indicating that TNFAIP8 is associated with the development of advanced ccRCC and poor prognosis. We subsequently confirmed that TNFAIP8 was abnormally overexpressed in clinical samples and ccRCC cell lines and that TNFAIP8 promoted ccRCC cell migration and invasion in vitro. Finally, we found that TNFAIP8 regulated EMT-related molecule expression and regulated the EMT process.

Conclusion: High expression of TNFAIP8 reinforces migration and regulates the EMT in ccRCC, conferring the metastatic potential of ccRCC and suggesting that TNFAIP8 may be a potential therapeutic target for the treatment of advanced ccRCC.

Molecular biology and targeted therapy in metastatic renal cell carcinoma

The treatment of metastatic renal cell carcinoma is challenging as it has proven to be relatively resistant to conventional oncological treatments. An improved understanding of the molecular biology of renal cell carcinoma has led to the development of a number of targeted therapies in metastatic renal cell carcinoma. This includes vascular endothelial growth factor inhibitors, tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors and most recently immune checkpoint inhibitors. This article will review the mechanisms of development and progression of renal cell carcinoma as well as the mechanisms of current approved treatments in metastatic disease.

Level of evidence: Not applicable for this multicentre audit.

A1CF-promoted colony formation and proliferation of RCC depends on DKK1-MEK/ERK signal axis

The function and mechanism of RNA editing proteins have been extensively studied, but its association with cellular processes and signaling pathways remained unaddressed. Here, we explored the function of RNA editing complementary protein- Apobec-1 Complementation Factor (A1CF) in the proliferation and colony formation of renal cell carcinoma (RCC) cells. Decreased A1CF expression inhibits the proliferation and colony formation of 786-O cells; and further signaling pathway screening demonstrated that A1CF increases ERK activation and DKK1 expression. Moreover, knockdown of DKK1 has similar phenotypes with A1CF deficiency in 786-O cells on cell proliferation and colony formation and ERK activation. Decreasing of DKK1 expression reduces the phosphorylation of ERK1/2 and MEK1/2 increased by A1CF overexpression; further, inhibiting of the phosphorylation of MEK1/2 by U0126 also decreases the ERK activation upregulated by A1CF overexpression. Deficiency of DKK1 or U0126 treatment suppresses the cell proliferation promoted by A1CF overexpression in 786-O cells; furthermore, U0126 treatment inhibits DKK1-increased cell proliferation in 786-O cells. Our results reveal that DKK1 mediates A1CF to activate ERK in promotion renal carcinoma cell proliferation and colony formation. For the important function of ERK signaling pathway in tumor metastasis and key position of DKK1 in Wnt signaling pathway, we associate RNA editing protein-A1CF with multiple cellular processes and signaling pathways through DKK1, and the key node of A1CF-DKK1-MEK/ERK axis is a potential targeting site for RCC therapy.

Inhibition of AIM2 inflammasome-mediated pyroptosis by Andrographolide contributes to amelioration of radiation-induced lung inflammation and fibrosis

Radiation-induced lung injury (RILI) is one of the most common and fatal complications of thoracic radiotherapy, whereas no effective interventions are available. Andrographolide, an active component extracted from Andrographis paniculate, is prescribed as a treatment for upper respiratory tract infection. Here we report the potential radioprotective effect and mechanism of Andrographolide on RILI. C57BL/6 mice were exposed to 18 Gy of whole thorax irradiation, followed by intraperitoneal injection of Andrographolide every other day for 4 weeks. Andrographolide significantly ameliorated radiation-induced lung tissue damage, inflammatory cell infiltration, and pro-inflammatory cytokine release in the early phase and progressive fibrosis in the late phase. Moreover, Andrographolide markedly hampered radiation-induced activation of the AIM2 inflammasome and pyroptosis in vivo. Furthermore, bone marrow-derived macrophages (BMDMs) were exposed to 8 Gy of X-ray radiation in vitro and Andrographolide significantly inhibited AIM2 inflammasome mediated-pyroptosis in BMDMs. Mechanistically, Andrographolide effectively prevented AIM2 from translocating into the nucleus to sense DNA damage induced by radiation or chemotherapeutic agents in BMDMs. Taken together, Andrographolide ameliorates RILI by suppressing AIM2 inflammasome mediated-pyroptosis in macrophage, identifying Andrographolide as a novel potential protective agent for RILI.