Black Phosphorus Quantum Dots Enhance the Radiosensitivity of Human Renal Cell Carcinoma Cells through Inhibition of DNA-PKcs Kinase.

Renal cell carcinoma (RCC) is one of the most aggressive urological malignancies and has a poor prognosis, especially in patients with metastasis. Although RCC is traditionally considered to be radioresistant, radiotherapy (RT) is still a common treatment for palliative management of metastatic RCC. Novel approaches are urgently needed to overcome radioresistance of RCC. Black phosphorus quantum dots (BPQDs) have recently received great attention due to their unique physicochemical properties and good biocompatibility. In the present study, we found that BPQDs enhance ionizing radiation (IR)-induced apoptotic cell death of RCC cells. BPQDs treatment significantly increases IR-induced DNA double-strand breaks (DSBs), as indicated by the neutral comet assay and the DSBs biomarkers γH2AX and 53BP1. Mechanistically, BPQDs can interact with purified DNA-protein kinase catalytic subunit (DNA-PKcs) and promote its kinase activity in vitro. BPQDs impair the autophosphorylation of DNA-PKcs at S2056, and this site phosphorylation is essential for efficient DNA DSBs repair and the release of DNA-PKcs from the damage sites. Consistent with this, BPQDs suppress nonhomologous end-joining (NHEJ) repair and lead to sustained high levels of autophosphorylated DNA-PKcs on the damaged sites. Moreover, animal experiments indicate that the combined approach with both BPQDs and IR displays better efficacy than monotreatment. These findings demonstrate that BPQDs have potential applications in radiosensitizing RCC cells.

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.

Stereotactic Radiotherapy for the Treatment of Patients With Oligo-progressive Metastatic Renal Cell Carcinoma Receiving Vascular Endothelial Growth Factor Receptor Tyrosine Kinase Inhibitor: Data From the Real World.

AIM: This retrospective observational study evaluated the role of hypo-fractionated stereotactic radiotherapy (SRT) in patients with oligo-progressive metastatic renal cell carcinoma (mRCC) treated with first-line oral tyrosine kinase inhibitors (TKI). Data on local control, delay of further progression, and safety are reported. PATIENTS AND METHODS: Between January 2010 and December 2016, 28 patients with mRCC who showed oligo-progressive disease while receiving first-line pazopanib were treated with hypofractionated SRT to progressive metastatic sites to delay the change of systemic therapy. First and second progression-free survival (PFS-1 and PFS-2) were recorded, as well as objective response and toxicity. RESULTS: After pazopanib therapy, nine partial remissions (32%), 12 stable disease (43%) and seven progressions (25%) were recorded. The median time to progression from first-line pazopanib until oligo-progression was 9.45 months (PFS-1 range=2-30 months). Seventeen patients (61%) showed progression at pre-existing tumor sites, and 11 patients (39%) showed the appearance of new metastases. Progression-free survival after radiation therapy was 4.55 months (PFS-2 range=1-11 months). PFS-1 plus PFS-2 was 14.0 months (range=3-41 months). Severe grade 3-4 toxicities were seen only occasionally. CONCLUSION: Patients with oligo-progressive mRCC treated with first-line pazopanib may benefit from hypo-fractionated high-dose SRT at progressing sites achieving a further increase in median progression-free survival. Further studies and prospective validation are required to establish if this minimally invasive approach may have a positive impact on overall survival and reported outcomes.

Radium-223 Dichloride in Combination with Vascular Endothelial Growth Factor-Targeting Therapy in Advanced Renal Cell Carcinoma with Bone Metastases.

Purpose: This study investigates the biologic activity of radium-223 with VEGF-targeted therapy in patients with advanced renal cell carcinoma (aRCC) and bone metastases.Patients and Methods: Fifteen treatment-naïve patients (n = 15) received pazopanib 800 mg orally once daily, and 15 previously treated patients received sorafenib 400 mg orally twice daily. Radium-223 55 kilobecquerel/kg was administered concurrently every 4 weeks for up to six infusions in both cohorts. The primary endpoint was decline in bone turnover markers (Procollagen I Intact N-Terminal, N-telopeptide, C-telopeptide, osteocalcin, and bone-specific alkaline phosphatase) compared with baseline. Secondary endpoints included safety, rate of symptomatic skeletal event (SSE) and time to first SSE, objective response rate, change in analgesic use, and quality of life. Exploratory analysis of tumor genomic alterations was performed.Results: Of the 30 patients enrolled, 83% had IMDC intermediate- or poor-risk disease, 33% had liver metastases, and 83% had a history of SSE prior to enrollment. No dose-limiting toxicity was observed. All bone turnover markers significantly declined from baseline at week 8 and 16. Forty percent of patients experienced treatment-related grade ≥3 adverse events. Response rates were 15% and 18% per RECIST v1.1 and bone response was 50% and 30% per MD Anderson criteria, in the pazopanib and sorafenib cohort, respectively. Median SSE-free interval was 5.8 months and not reached, respectively. Analgesic use remained stable over the study time.Conclusions: Radium-223 combined with VEGF-targeted therapy is biologically active and safe. Randomized-controlled trials are needed to define the role of radium-223 in aRCC with skeletal metastases. Clin Cancer Res; 24(17); 4081-8. ©2018 AACR.

Recent advances in the management of renal cell carcinoma-a radiation oncology perspective.

Renal cell carcinoma (RCC) is a rare cancer in developing countries like Nigeria. However, with an increasing understanding of its epidemiology, the increasing availability of trained personnel, improvement in diagnostic facilities, and greater awareness in the populace, an increase in its incidence as was witnessed in developed nations in the last few decades could be safely predicted. This narrative review highlights the international best practices in the multidisciplinary approach to the management of RCC, its diagnosis and treatment, with emphasis on recent advances and radiation treatment. The National Comprehensive Cancer Network (NCCN) guideline (version 3.2015) served as a guide to select relevant articles through a PubMed and Google scholar query.

Radiation recall dermatitis triggered by multi-targeted tyrosine kinase inhibitors: sunitinib and sorafenib.

Small molecule tyrosine kinase inhibitors are rapidly being integrated into the management of cancer. This is the first report of sorafenib and sunitinib, both small molecule tyrosine kinase inhibitors of vascular endothelial growth factor and platelet-derived growth factor receptors, triggering radiation recall dermatitis. The pathophysiology of radiation recall is poorly understood, and several possible mechanisms have been proposed. The clinical presentations of these two cases were consistent with one hypothesized mechanism of radiation recall, an idiosyncratic drug hypersensitivity reaction.

Multidisciplinary treatment including sorafenib stabilized the bone metastases of renal cell carcinoma in an immunosuppressed renal transplant recipient.

We report a case of metastatic renal cell carcinoma in the native kidney of a renal transplant recipient. The patient was a 57-year-old man in whom a tumor in the native kidney and bone metastasis were found incidentally on imaging, 10 years after cadaveric renal transplantation. Interferon-alpha was administered after nephrectomy and following palliative irradiation of the metastasis, but could not be continued because of allograft dysfunction. Subsequent administration of zoledronic acid and sorafenib stabilized the disease for 18 months after nephrectomy. This is the first reported case of sorafenib administration to a renal transplant recipient with metastatic renal cell carcinoma.

Radiation therapy and sorafenib: clinical data and rationale for the combination in metastatic renal cell carcinoma.

Sorafenib, an inhibitor of multiple tyrosine kinases including vascular endothelial growth factor receptor and Raf/mitogen-activated protein kinase, increases progression-free survival in metastatic renal cell carcinoma (RCC) compared with placebo. The efficacy and toxicity of combined sorafenib and radiation therapy (RT) in the treatment of RCC are unknown. This is a retrospective report of 3 consecutive patients with metastatic or locally recurrent RCC treated with palliative RT while undergoing sorafenib therapy. All 3 patients experienced disease progression on sorafenib and remained on the drug without dose reduction during the RT plus sorafenib regimen. They were followed for toxicity and response by clinical history, physical examination, and contrast-enhanced computed tomography scans. Soon after completion of palliative RT, all 3 patients experienced complete pain relief without the need for narcotic pain medication. Posttreatment imaging revealed partial response with > 50% regression of tumor in all patients. None reported significant acute or late side effects at follow-up of 3, 6, and 8 months after RT and sorafenib. In the 3 patients with recurrent or metastatic RCC in this report, the combination of RT and sorafenib was well tolerated and resulted in excellent clinical and radiologic responses. This combination is promising and requires further study.

Lack of efficacy of two consecutive treatments of radioimmunotherapy with 131I-cG250 in patients with metastasized clear cell renal cell carcinoma.

PURPOSE: A previous activity dose-escalation study using 131I-labeled chimeric monoclonal antibody cG250 in patients with progressive metastatic renal cell carcinoma (RCC) resulted in occasional therapeutic responses. The present study was designed to determine the safety and therapeutic efficacy of two sequential high-dose treatments with 131I-cG250. PATIENTS AND METHODS: Patients (n = 29) with progressive metastatic RCC received a low dose of (131)I-cG250 for assessment of preferential targeting of metastatic lesions, followed by the first radioimmunotherapy (RIT) with 2220 MBq/m2 131I-cG250 (n = 27) 1 week later. If no grade 4 hematologic toxicity was observed, a second low-dose 131I-cG250 (n = 20) was given 3 months later. When blood clearance was not accelerated, a second RIT of 131I-cG250 was administered at an activity-dose of 1110 MBq/m2 (n = 3) or 1665 MBq/m2 (n = 16). Patients were monitored weekly for toxicity, and tumor size was evaluated by computed tomography once every 3 months intervals. RESULTS: The maximum-tolerated dose (MTD) of the second RIT was 1,665 MBq/m2 because of dose-limiting hematological toxicity. Based on an intention-to-treat analysis, after two RIT treatments, the disease stabilized in five of 29 patients, whereas it remained progressive in 14 of 29 patients. Two patients received no RIT, and eight of 29 received only one 131I-cG250 RIT because of grade 4 hematologic toxicity, formation of human antichimeric antibodies, or disease progression. CONCLUSION: In patients with progressive end-stage RCC, the MTD of the second treatment was 75% of the MTD of the first RIT. In the majority of patients, two cycles of 131I-cG250 could be safely administered without severe toxicity. No objective responses were observed, but occasionally two RIT doses resulted in stabilization of previously progressive disease.

Successful treatment of radiation-induced brain necrosis by hyperbaric oxygen therapy.

We describe a 68-year-old man who underwent hyperbaric oxygen (HBO) therapy to manage radiation necrosis of the brain, which developed after two treatments with stereotactic radiosurgery (SRS) to the same lesion. The necrosis was subsequently treated with steroids alone for 2 months; however, he progressed clinically and radiographically. Improvement again was noted with the reinstitution of HBO therapy. This case suggests that HBO therapy is an important therapeutic option in the treatment of brain radiation necrosis caused by SRS.

Targeting hyperthermia for renal cell carcinoma using human MN antigen-specific magnetoliposomes.

Magnetoliposomes (MLs) conjugated with an antibody fragment to give specificity to a tumor were applied to hyperthermia for cancer. The Fab' fragment of the G250 antibody, which binds to MN antigen on many types of human renal cell carcinoma, was cross-linked to N-(6-maleimidocaproyloxy)-dipalmitoyl phosphatidylethanolamine (EMC-DPPE) in liposomal membrane. The targetability of the G250-Fab' fragment-conjugating MLs (G250-FMLs) was investigated using the mouse renal cell carcinoma (mRCC) and MN antigen-presenting cell, MN-mRCC. The amount of G250-FMLs uptake reached 67 pg / cell against MN-mRCC cells in an in vitro experiment using plastic dishes and this value was about 6 times higher than that in the case of MLs. In an in vivo experiment using MN-mRCC-harboring mice, 1.5 mg of the FMLs per carcinoma tissue accumulated (tumor weight was 0.19 g), which corresponded to approximately 50% of the total injection. This value was 27 times higher than that of the MLs. After injection of the FMLs, mice were exposed to intracellular hyperthermia using alternating magnetic field irradiation. The temperature of tumor tissue increased to 43 degrees C and the growth of the carcinoma was strongly arrested for at least 2 weeks. These results indicate the G250-FMLs could target renal cell carcinoma cells in vitro and in vivo, and are efficiently applicable to the hyperthermic treatment of carcinoma.

Phase I radioimmunotherapy of metastatic renal cell carcinoma with 131I-labeled chimeric monoclonal antibody G250.

Clinical tumor targeting studies with chimeric monoclonal antibody G250 (cG250) in renal cell carcinoma (RCC) patients indicated the potential use of this antibody for radioimmunotherapy. Here we report on a phase I activity dose escalation study to determine the safety, the maximum tolerable dose (MTD), and the possible therapeutic potential of 131I-labeled cG250 in patients with progressive metastatic RCC. All patients (n = 12) received a diagnostic i.v. infusion of 5 mg of cG250 labeled with 222 MBq of 131I. If accumulation of the antibody in metastatic lesions was observed, patients were hospitalized and a second, therapeutic, i.v. infusion of 5 mg of cG250 labeled with a high dose of 131I was administered (n = 8). Three patients per dose level were entered, starting at 1665 MBq/m2. If no dose-limiting toxicity occurred, the study continued at the next dose level (555 MBq/m2 increase). Most patients experienced mild nausea without vomiting. No other complaints were reported during hospitalization. In two of two patients who received a dose of 2775 MBq/m2, grade IV hematological toxicity was observed, which was defined as dose limiting. Thus, the MTD was set at 2220 MBq/m2. In one patient (2220 MBq/m2), stable disease (lasting 3-6 months) was achieved, whereas another patient (2220 MBq/m2) showed a partial response that is ongoing (>9 months). The minor responses observed in this phase I trial in patients with an advanced stage of RCC are encouraging and warrant further study in a phase II setting at the MTD to determine the efficacy of radioimmunotherapy for metastatic RCC.

Case report: localization of lipiodol-radioiodine in hepatic metastases from renal cell carcinoma.

Lipiodol, an iodinated derivative of poppyseed oil, is selectively retained in hepatocellular carcinoma and has been used as a vehicle to deliver localized doses of chemotherapeutic and radioactive agents to such tumours, thereby reducing the problems of external beam irradiation and the systemic toxicity of chemotherapy. We describe the first reported case where Lipiodol-targeted radiotherapy has been administered to a patient with secondary renal cell carcinoma in the liver. Localization was good and there were no complications. This case suggests that in future such patients may benefit from this therapy for unresectable lesions.

Irradiation-induced duodenal ulcer disease refractory to ranitidine: healing by omeprazole.

In two patients duodenal ulcer refractory to high dose H2-blocker treatment started several months after irradiation therapy following right nephrectomy because of renal adenocarcinoma. Established antiulcer drugs like ranitidine, famotidine, sucralfate, pirenzepine, and antacids alone or in combination were unable to control ulcer pain and failed to induce ulcer healing. Initiation of omeprazole treatment at dosages to produce complete achlorhydria were necessary for ulcer healing and maintenance therapy. We suggest that (a) irradiation may cause duodenal ulcer disease indistinguishable from idiopathic duodenal ulcer; (b) radiation-induced ulcers in the duodenal bulb are refractory to various antiulcer drugs but may heal after administration of omeprazole in dosages that completely suppress acid secretion.

[A combined treatment of interferon-alpha, 8 MHz radiofrequency hyperthermia and/or irradiation in a patient with advanced renal cancer].

A combined treatment of alpha interferon (INF), 8 MHz radiofrequency (RF) hyperthermia using Thermotron-RF Model 8 and/or irradiation was performed on a patient with advanced renal cancer. The patient was a 52-year-old male, who had received arterial embolization with a gelatin sponge and 60 mg of adriamycin for the right renal tumor in January, 1985. He was referred to our clinic in April, 1985. Computed tomography showed a right renal tumor, 120 x 105 x 80 mm. Histological examination revealed clear cell carcinoma of the right kidney. The tumor was unresectable because of the huge tumor size, invasion into the right lobe of the liver, multiple pulmonary metastases and severe dysproteinemia. From the beginning of May, 1985, administration of 3 x 10(6) units interferon-alpha (INF) daily and radiofrequency (RF)hyperthermia for one hour twice a week were started. By June 11, 1985, 10 sessions of RF-hyperthermia were performed. Thereafter, hyperthermia for the renal tumor was maintained once a week until June, 1986. From the middle of June, 1985, a gradual improvement of dysproteinemia and appetite loss, and a decrease of the right renal tumor size as well as disappearance of febrile attacks were attained. In November, 1985, mediastinal lymph node swelling developed. A combined therapy of RF-hyperthermia twice a week and irradiation with 2.0 Gy daily 5 times a week was started. A total of 14 sessions of RF-hyperthermia and 30 Gy of irradiation were delivered until January, 1986. Intratumoral temperature of the renal tumor reached 44.0 degrees C during the heating.(ABSTRACT TRUNCATED AT 250 WORDS)

[Combined treatment of irradiation and 8 MHz radiofrequency hyperthermia with chemoembolization in advanced renal tumor].

A combined treatment of irradiation and 8 MHz radiofrequency hyperthermia after chemoembolization, using 20 mg of microencapsulated mitomycin C (MMC.mc), was undertaken in a patient with an advanced left renal tumor. The patient, a 70-year-old man, noticed a gross hematuria in February, 1984. CT showed a left renal tumor, 88 X 70 mm in size. Histological examination revealed clear cell carcinoma of the left kidney. The tumor was unresectable because of an invasion into the surrounding tissues. Chemoembolization was performed before the combined treatment of irradiation and hyperthermia. He received 23.2 Gy of irradiation and 10 sessions of hyperthermia. Intratumoral temperature reached 42.6 degrees C during the heating. After treatment, there was a tumor regression rate of 58%, as well as pain relief, and an improvement in his appetite loss. He died 8 months after this treatment. An autopsy specimen revealed bionecrotic tumor cells among the prominent necrotic and fibrotic tissues.