Postoperative Metabolic Phenoreversion in Clear Cell Renal Cell Carcinoma.

The ultimate goal of surgical treatment in cancer is to remove the tumor mass for restoring a healthy state. A 16-lipid panel that discriminated healthy controls from clear cell renal cell carcinoma (ccRCC) patients in a prior study was evaluated in the present work in paired-serum samples collected from patients (n = 41) before and after nephrectomy. Changes in the lipid and metabolite fingerprints from ccRCC patients were investigated and compared with fingerprints from healthy individuals obtained by means of ultra-performance liquid chromatography-high-resolution mass spectrometry. The lipid panel differentiated phenotypes associated with metabolic restoration after surgery, representing a serum signature of phenoreversion to a healthy metabolic state. In particular, PC 16:0/0:0, PC 18:2/18:2, and linoleic acid allowed discriminating serum samples from ccRCC patients with poor prognosis from those with an improved outcome during the follow-up period. Ratios of PC 16:0/0:0 and PC 18:2/18:2 with linoleic acid levels may contribute as prognostic tools to support decision-making during the patient follow-up care. The preliminary character of these results should be validated with larger cohorts, including subjects with different ethnicities, life style, and diets. MetaboLights study references: MTBLS1839, MTBLS3838, and MTBLS4629.

miR-378a-3p promotes renal cell carcinoma proliferation, migration, and invasion by targeting TOB2.

PURPOSE: Renal cell carcinoma (RCC) is one of the most common malignant tumors of the urinary system, which has high metastasis. MicroRNAs (miRNAs) have been reported to participate in RCC progression. The present study aimed to understand the biological role and mechanism of miR-378a-3p in RCC. METHODS: RT-qPCR assay was used to assess miR-378a-3p and transducer of ERBB2 (TOB2) expression in RCC tissues and cell lines. CCK-8, clone formation, scratch, and transwell assays were carried out to evaluate cell proliferation, migration, and invasion. Furthermore, the target genes of miR-378a-3p were predicted by the online bioinformatics databases. Dual-luciferase reporter assay was used to validate the relationship between miR-378a-3p and TOB2. RESULTS: miR-378a-3p was highly expressed in RCC tissues and RCC cell lines. Besides, miR-378a-3p accelerated the progression of RCC by mediating cell proliferation, migration and invasion. More importantly, TOB2 was confirmed as a potential target gene of miR-378a-3p. The results of loss-of-function experiments showed that inhibition of TOB2 reversed the inhibitory roles of miR-378a-3p inhibitor on RCC progression. CONCLUSIONS: miR-378a-3p promoted cell proliferation, migration and invasion through regulating TOB2 in RCC, which indicated a promising target for the treatment of RCC.

Mitigating the prevalence and function of myeloid-derived suppressor cells by redirecting myeloid differentiation using a novel immune modulator.

BACKGROUND: Immune suppression is common in neoplasia and a major driver is tumor-induced myeloid dysfunction. Yet, overcoming such myeloid cell defects remains an untapped strategy to reverse suppression and improve host defense. Exposure of bone marrow progenitors to heightened levels of myeloid growth factors in cancer or following certain systemic treatments promote abnormal myelopoiesis characterized by the production of myeloid-derived suppressor cells (MDSCs) and a deficiency in antigen-presenting cell function. We previously showed that a novel immune modulator, termed 'very small size particle' (VSSP), attenuates MDSC function in tumor-bearing mice, which was accompanied by an increase in dendritic cells (DCs) suggesting that VSSP exhibits myeloid differentiating properties. Therefore, here, we addressed two unresolved aspects of the mechanism of action of this unique immunomodulatory agent: (1) does VSSP alter myelopoiesis in the bone marrow to redirect MDSC differentiation toward a monocyte/macrophage or DC fate? and (2) does VSSP mitigate the frequency and suppressive function of human tumor-induced MDSCs? METHODS: To address the first question, we first used a murine model of granulocyte-colony stimulating factor-driven emergency myelopoiesis following chemotherapy-induced myeloablation, which skews myeloid output toward MDSCs, especially the polymorphonuclear (PMN)-MDSC subset. Following VSSP treatment, progenitors and their myeloid progeny were analyzed by immunophenotyping and MDSC function was evaluated by suppression assays. To strengthen rigor, we validated our findings in tumor-bearing mouse models. To address the second question, we conducted a clinical trial in patients with metastatic renal cell carcinoma, wherein 15 patients were treated with VSSP. Endpoints in this study included safety and impact on PMN-MDSC frequency and function. RESULTS: We demonstrated that VSSP diminished PMN-MDSCs by shunting granulocyte-monocyte progenitor differentiation toward monocytes/macrophages and DCs with heightened expression of the myeloid-dependent transcription factors interferon regulatory factor-8 and PU.1. This skewing was at the expense of expansion of granulocytic progenitors and rendered the remaining MDSCs less suppressive. Importantly, these effects were also demonstrated in a clinical setting wherein VSSP monotherapy significantly reduced circulating PMN-MDSCs, and their suppressive function. CONCLUSIONS: Altogether, these data revealed VSSP as a novel regulator of myeloid biology that mitigates MDSCs in cancer patients and reinstates a more normal myeloid phenotype that potentially favors immune activation over immune suppression.

Phenotypical screening on metastatic PRCC-TFE3 fusion translocation renal cell carcinoma organoids reveals potential therapeutic agents.

PURPOSE: Translocation renal cell carcinoma (tRCC) is a subtype that occurs predominantly in children and young individuals. Metastatic tRCC occurring in young patients is more aggressive than that occurring in older patients, and there are still no effective therapies. Organoids can mimic original tissues and be assessed by high-throughput screening (HTS). We aimed to utilize patient-derived organoids and HTS to screen drugs that can be repurposed for metastatic tRCC with PRCC-TFE3 fusion. METHODS: Tumor tissues were obtained from treatment-naïve metastatic tRCC patients who underwent surgery. Histopathology and fluorescence in situ hybridization (FISH) confirmed the tRCC. Organoids derived from the dissected tissues were cultured and verified by FISH and RNA-seq. HTS was performed to seek promising drugs, and potential mechanisms were explored by RNA-seq and cell-based studies. RESULTS: We successfully established a metastatic tRCC organoid with PRCC-TFE3 fusion, a common fusion subtype, and its characteristics were verified by histopathology, FISH, and RNA-seq. An HTS assay was developed, and the robustness was confirmed. A compound library of 1816 drugs was screened. Eventually, axitinib, crizotinib, and JQ-1 were selected for further validation and were found to induce cell cycle arrest and apoptosis. RNA-seq analyses of posttreatment organoids indicated that crizotinib induced significant changes in autophagy-related genes, consistent with the potential pathogenesis of tRCC. CONCLUSIONS: We established and validated organoids derived from tissues dissected from a patient with metastatic tRCC with PRCC-TFE3 fusion and achieved the HTS process for the first time. Crizotinib might be a targeted therapy worthy of exploration in the clinic for metastatic tRCC with PRCC-TFE3 fusion. Such organoid and HTS assays may represent a promising model system in translational research assisting in the development of clinical strategies.

Tumor-Experienced Human NK Cells Express High Levels of PD-L1 and Inhibit CD8+ T Cell Proliferation.

Natural Killer (NK) cells play a key role in cancer immunosurveillance. However, NK cells from cancer patients display an altered phenotype and impaired effector functions. In addition, evidence of a regulatory role for NK cells is emerging in diverse models of viral infection, transplantation, and autoimmunity. Here, we analyzed clear cell renal cell carcinoma (ccRCC) datasets from The Cancer Genome Atlas (TCGA) and observed that a higher expression of NK cell signature genes is associated with reduced survival. Analysis of fresh tumor samples from ccRCC patients unraveled the presence of a high frequency of tumor-infiltrating PD-L1+ NK cells, suggesting that these NK cells might exhibit immunoregulatory functions. In vitro, PD-L1 expression was induced on NK cells from healthy donors (HD) upon direct tumor cell recognition through NKG2D and was further up-regulated by monocyte-derived IL-18. Moreover, in vitro generated PD-L1hi NK cells displayed an activated phenotype and enhanced effector functions compared to PD-L1- NK cells, but simultaneously, they directly inhibited CD8+ T cell proliferation in a PD-L1-dependent manner. Our results suggest that tumors might drive the development of PD-L1-expressing NK cells that acquire immunoregulatory functions in humans. Hence, rational manipulation of these regulatory cells emerges as a possibility that may lead to improved anti-tumor immunity in cancer patients.

Circulating and Tumor-Infiltrating NK Cells From Clear Cell Renal Cell Carcinoma Patients Exhibit a Predominantly Inhibitory Phenotype Characterized by Overexpression of CD85j, CD45, CD48 and PD-1.

Although natural killer (NK) cells infiltrate clear cell renal cell carcinomas (ccRCC), the most frequent malignancy of the kidney, tumor progression suggests that they become dysfunctional. As ccRCC-driven subversion of NK cell effector functions is usually accompanied by phenotypic changes, analysis of such alterations might lead to the identification of novel biomarkers and/or targets in immuno-oncology. Consequently, we performed a phenotypic analysis of peripheral blood NK cells (PBNK) and tumor-infiltrating NK cells (TINK) from ccRCC patients. Compared to HD, PBNK from ccRCC patients exhibited features of activated cells as shown by CD25, CD69 and CD62L expression. They also displayed increased expression of DNAM-1, CD48, CD45, MHC-I, reduced expression of NKG2D, and higher frequencies of CD85j+ and PD-1+ cells. In addition, compared to PBNK from ccRCC patients, TINK exhibited higher expression of activation markers, tissue residency features and decreased expression of the activating receptors DNAM-1, NKp30, NKp46, NKp80 and CD16, suggesting a more inhibitory phenotype. Analysis of The Cancer Genome Atlas (TCGA) revealed that CD48, CD45, CD85j and PD-1 are significantly overexpressed in ccRCC and that their expression is associated with an NK cell infiltration signature. Calculation of z-scores revealed that their expression on PBNK, alone or combined, distinguished ccRCC patients from HD. Therefore, these molecules emerge as novel potential biomarkers and our results suggest that they might constitute possible targets for immunotherapy in ccRCC patients.

Multidrug resistance protein 4 (MRP4/ABCC4) is overexpressed in clear cell renal cell carcinoma (ccRCC) and is essential to regulate cell proliferation.

Kidney cancer accounts for 2.5% of all cancers, with an annual global incidence of almost 300,000 cases leading to 111,000 deaths. Approximately 85% of kidney tumors are renal cell carcinoma (RCC) and their major histologic subtype is clear cell renal cell carcinoma (ccRCC). Although new therapeutic treatments are being designed and applied based on the combination of tyrosine kinase inhibitors and immunotherapy, no major impact on the mortality has been reported so far. MRP4 is a pump efflux that transporters multiple endogenous and exogenous substances. Recently it has been associated with tumoral persistence and cell proliferation in several types of cancer including pancreas, lung, ovary, colon, ostesarcoma, etc. Herein, we demonstrate for the first time, that MRP4 is overexpressed in ccRCC tumors, compared to control renal tissues. In addition, using cell culture models, we observed that MRP4 pharmacological inhibition produces an imbalance in cAMP metabolism, induces cell arrest, changes in lipid composition, increase in cytoplasmic lipid droplets and finally apoptosis. These data provide solid evidence for the future evaluation of MRP4 as a possible new therapeutic target in ccRCC.

Untargeted Contrast-Enhanced Ultrasound Versus Contrast-Enhanced Computed Tomography: A Differential Diagnostic Performance (DDP) Study for Kidney Lesions.

OBJECTIVES: Histopathology is the 'gold standard' for diagnosing renal cell carcinoma but is limited by sample size. Contrast-enhanced ultrasound can differentiate malignant and benign lesions, but the Chinese guidelines on the management of renal cell carcinoma do not include this method. The purpose of this study was to compare the diagnostic parameters of contrast-enhanced ultrasound against those of contrast-enhanced computed tomography for detecting kidney lesions, with histopathology considered the reference standard. METHODS: Patients with suspected kidney lesions from prior grayscale ultrasonography and computed tomography were included in the analysis (n=191). The contrast-enhanced ultrasound, contrast-enhanced computed tomography, and histopathology data were collected and analyzed. A solid, enhanced mass was considered a malignant lesion, and an unenhanced mass or cyst was considered a benign lesion. The Bosniak criteria were used to characterize the lesions. RESULTS: Contrast-enhanced ultrasound and contrast-enhanced computed tomography both detected that 151 patients had malignant tumors and 40 patients had benign tumors. No significant differences in the tumors and their subtypes were reported between contrast-enhanced ultrasound and histopathology (p=0.804). Chromophobe renal cell carcinoma was detected through contrast-enhanced computed tomography (n=1), but no such finding was reported by contrast-enhanced ultrasound. A total of 35 cases of papillary renal cell carcinoma were reported through contrast-enhanced ultrasound while 32 were reported through histopathology. CONCLUSIONS: Contrast-enhanced ultrasound might be safe and as accurate as histopathology in diagnosing kidney lesions, especially renal cell carcinoma. Additionally, this study provides additional information over histopathology and has an excellent safety profile. LEVEL OF EVIDENCE: III.

A new scenario in metastatic renal cell carcinoma: a SOG-GU consensus.

BACKGROUND: This article describes and compares approved targeted therapies and the newer immunotherapy agents. MATERIALS AND METHODS: This article especially performs an in-depth review of currently available data for tivozanib, explaining its mechanism of action, its safety profile and its role as an efficacy drug in the management of renal cancer. RESULTS: Despite the fact that the treatment of advanced RCC has been dramatically modified in recent years, durable remissions are scarce and it remains a lethal disease. For first- and second-line therapy, there is now growing evidence to guide the selection of the appropriate treatment. CONCLUSIONS: Several TKIs are standard of care at different settings. Among those approved TKIs, tivozanib has similar efficacy than others with a better safety profile. The use of prognostic factors is critical to the selection of optimal therapy.

S-(4-Methoxyphenyl)-4-methoxybenzenesulfonothioate as a Promising Lead Compound for the Development of a Renal Carcinoma Agent.

Organosulfur compounds show cytotoxic potential towards many tumor cell lines. Disulfides and thiosulfonates act through apoptotic processes, inducing proteins associated with apoptosis, endoplasmic reticulum stress, and the unfolded protein response. Three p-substituted symmetric diaryl disulfides and three diaryl thiosulfonates were synthesized and analyzed for inhibition of tubulin polymerization and for human cancer cell cytotoxic activity against seven tumor cell lines and a non-tumor cell line. S-(4-methoxyphenyl)-4-methoxybenzenesulfonothioate (6) exhibited inhibition of tubulin polymerization and showed the best antiproliferative potential, especially against the 786-0 cell line, being six times more selective as compared with the non-tumor cell line. In addition, compound 6 was able to activate caspase-3 after 24 and 48 h treatments of the 786-0 cell line and induced cell-cycle arrest in the G2/M stage at the highest concentration evaluated at 24 and 48 h. Compound 6 was able to cause complete inhibition of proliferation, inducing the death of 786-0 cells, by increasing the number of cells at G2/M and greater activation of caspase-3.

Untargeted contrast-enhanced ultrasound versus contrast-enhanced computed tomography: a differential diagnostic performance (DDP) study for kidney lesions

OBJECTIVES: Histopathology is the 'gold standard' for diagnosing renal cell carcinoma but is limited by sample size. Contrast-enhanced ultrasound can differentiate malignant and benign lesions, but the Chinese guidelines on the management of renal cell carcinoma do not include this method. The purpose of this study was to compare the diagnostic parameters of contrast-enhanced ultrasound against those of contrast-enhanced computed tomography for detecting kidney lesions, with histopathology considered the reference standard. METHODS: Patients with suspected kidney lesions from prior grayscale ultrasonography and computed tomography were included in the analysis (n=191). The contrast-enhanced ultrasound, contrast-enhanced computed tomography, and histopathology data were collected and analyzed. A solid, enhanced mass was considered a malignant lesion, and an unenhanced mass or cyst was considered a benign lesion. The Bosniak criteria were used to characterize the lesions. RESULTS: Contrast-enhanced ultrasound and contrast-enhanced computed tomography both detected that 151 patients had malignant tumors and 40 patients had benign tumors. No significant differences in the tumors and their subtypes were reported between contrast-enhanced ultrasound and histopathology (p=0.804). Chromophobe renal cell carcinoma was detected through contrast-enhanced computed tomography (n=1), but no such finding was reported by contrast-enhanced ultrasound. A total of 35 cases of papillary renal cell carcinoma were reported through contrast-enhanced ultrasound while 32 were reported through histopathology. CONCLUSIONS: Contrast-enhanced ultrasound might be safe and as accurate as histopathology in diagnosing kidney lesions, especially renal cell carcinoma. Additionally, this study provides additional information over histopathology and has an excellent safety profile. Level of evidence: III.

von Hippel-Lindau mutants in renal cell carcinoma are regulated by increased expression of RSUME.

Renal cell carcinoma (RCC) is the major cause of death among patients with von Hippel-Lindau (VHL) disease. Resistance to therapies targeting tumor angiogenesis opens the question about the underlying mechanisms. Previously we have described that RWDD3 or RSUME (RWD domain-containing protein SUMO Enhancer) sumoylates and binds VHL protein and negatively regulates HIF degradation, leading to xenograft RCC tumor growth in mice. In this study, we performed a bioinformatics analysis in a ccRCC dataset showing an association of RSUME levels with VHL mutations and tumor progression, and we demonstrate the molecular mechanism by which RSUME regulates the pathologic angiogenic phenotype of VHL missense mutations. We report that VHL mutants fail to downregulate RSUME protein levels accounting for the increased RSUME expression found in RCC tumors. Furthermore, we prove that targeting RSUME in RCC cell line clones carrying missense VHL mutants results in decreased early tumor angiogenesis. The mechanism we describe is that RSUME sumoylates VHL mutants and beyond its sumoylation capacity, interacts with Type 2 VHL mutants, reduces HIF-2α-VHL mutants binding, and negatively regulates the assembly of the Type 2 VHL, Elongins and Cullins (ECV) complex. Altogether these results show RSUME involvement in VHL mutants deregulation that leads to the angiogenic phenotype of RCC tumors.

CEP55 promotes epithelial-mesenchymal transition in renal cell carcinoma through PI3K/AKT/mTOR pathway.

PURPOSE: To study the detailed mechanisms of tumorigenesis and clinical outcomes of centrosomal protein 55 (CEP55) overexpression in renal cell carcinoma. MATERIALS AND METHODS: Microarray analysis was performed to explore differentially expressed genes in five pairs of RCC tissues. Data of CEP55 expression and corresponding clinical information for 532 RCC patients of TCGA database were downloaded from cBioPortal. The expression of CEP55 in RCC tissues and cells was determined by real-time quantitative reverse transcription PCR (qRT-PCR), Western blot analysis and immunohistochemistry (IHC). Cells were transfected with siRNAs or lentivirus to regulate the expression of CEP55. The effects of CEP55 on proliferation, migration, invasion and epithelial-to-mesenchymal transition (EMT) of RCC cells were determined by MTS, migration and invasion assay and Western blot analysis. RESULTS: CEP55, one of the most upregulated genes in microarray analysis, was overexpressed in RCC tissues and cells. CEP55 expression was significantly correlated with poor outcome including neoplasm disease stage, histologic grade and TNM status, as well as survival status of patients. In vitro experiments showed that downregulation of CEP55 could dramatically inhibit RCC cell proliferation, migration and invasion, while overexpression of CEP55 could promote these biological behaviors. We further demonstrated that CEP55 knockdown suppressed epithelial-mesenchymal transition (EMT), which was mediated via upregulation of E-cadherin and downregulation of N-cadherin and ZEB1, through PI3K/AKT/mTOR pathway. In contrast, overexpression of CEP55 could promote EMT in RCC cells via the activation of PI3K/AKT/mTOR pathway. Importantly, inhibition of PI3K/AKT/mTOR pathway reduced the effects of CEP55 on the migration, invasion and EMT of RCC cells. CONCLUSION: Our study showed that CEP55 could promote EMT through PI3K/AKT/mTOR pathway and might be an effective prognostic marker in RCC.

Prognostic significance of the dynamic changes of systemic inflammatory response in metastatic renal cell carcinoma

ABSTRACT Purpose: To elucidate the prognostic value of systemic inflammatory response in patients with metastatic renal cell carcinoma (mRCC) who are treated with sunitinib, we evaluated the prognostic role of C-reactive protein (CRP) kinetics. This study also compared prognostic models containing CRP kinetics and neutrophil-to-lymphocyte ratio (NLR) kinetics. Materials and Methods: A consecutive cohort of 94 patients with mRCC who were treated with sunitinib was retrospectively included from Fudan University Shanghai Cancer Center. According to dynamic changes in CRP and the NLR, patients were divided into three groups for analysis of CRP and NLR kinetics. The associations between survival and potential prognostic factors were assessed. The incremental value of prognostication was evaluated. Results: A significant difference (P<0.001) in overall survival (OS) was observed among the three groups of CRP kinetics. The median OS of the non-elevated group was nearly 1.3-fold longer than that of the normalized group (33.0 vs. 26.3 months), and two times longer than that of the non-normalized group (33.0 vs. 14.0 months). Multivariate analysis showed that CRP and NLR kinetics were independent prognostic indicators. The model containing CRP kinetics had a better predictive accuracy than that with NLR kinetics, which was supported by the C-index (0.731 vs. 0.684) and the likelihood ratio χ2 test (79.9% vs. 44.9%). Conclusion: Our study suggests that dynamic changes in CRP can better predict survival in patients with mRCC who are treated with sunitinib. Routine assessment of CRP before and after targeted therapy would help identify patients at risk of a poor outcome.

Immunohistochemical expressionof sodium-dependent glucose transporter - 2 (SGLT-2) in clear cell renal carcinoma: possible prognostic implications

ABSTRACT Purpose: Glucose is a major energy resource for tumor cell survival and growth, and its influx into cells is mainly carried out by facilitative glucose transporters (GLUTs). Sodium - dependent glucose transporters (SGLTs) have been highlighted as playing important roles in diabetic treatment. However, their potential roles in cancer remain unclear. We examined expression patterns of SGLTs in tumor tissues together with conventional pathological variables to determine prognostic significance in patients with renal cell carcinoma (RCC). Materials and Methods: Nephrectomy specimens were obtained from 68 patients. GLUT - 1, - 2 and SGLT - 1, - 2 expression in tumor and adjacent normal tissues were analyzed by immunohistochemical staining, and intensity was quantified using an image analyzer. Results: The four glucose transporters evaluated were broadly distributed in tumor tissues as well as throughout the normal parenchyma. There was no significant correlation between transporter expression and conventional pathological variables. However, increased SGLT - 2 expression was significantly associated with shorter overall survival (p < 0.01), regardless of metastatic status. Conclusions: We propose possible prognostic significance of SGLT - 2 expression in human RCC. Given that glucose is a major energy resource for tumor cells and that glucose transport is largely mediated by SGLT, SGLT - 2 may serve as a possible therapeutic target in RCC.

Prognostic significance of the dynamic changes of systemic inflammatory response in metastatic renal cell carcinoma.

PURPOSE: To elucidate the prognostic value of systemic inflammatory response in patients with metastatic renal cell carcinoma (mRCC) who are treated with sunitinib, we evaluated the prognostic role of C-reactive protein (CRP) kinetics. This study also compared prognostic models containing CRP kinetics and neutrophil-to-lymphocyte ratio (NLR) kinetics. MATERIALS AND METHODS: A consecutive cohort of 94 patients with mRCC who were treated with sunitinib was retrospectively included from Fudan University Shanghai Cancer Center. According to dynamic changes in CRP and the NLR, patients were divided into three groups for analysis of CRP and NLR kinetics. The associations between survival and potential prognostic factors were assessed. The incremental value of prognostication was evaluated. RESULTS: A significant difference (P<0.001) in overall survival (OS) was observed among the three groups of CRP kinetics. The median OS of the non-elevated group was nearly 1.3-fold longer than that of the normalized group (33.0 vs. 26.3 months), and two times longer than that of the non-normalized group (33.0 vs. 14.0 months). Multivariate analysis showed that CRP and NLR kinetics were independent prognostic indicators. The model containing CRP kinetics had a better predictive accuracy than that with NLR kinetics, which was supported by the C-index (0.731 vs. 0.684) and the likelihood ratio χ² test (79.9% vs. 44.9%). CONCLUSION: Our study suggests that dynamic changes in CRP can better predict survival in patients with mRCC who are treated with sunitinib. Routine assessment of CRP before and after targeted therapy would help identify patients at risk of a poor outcome.

Immunohistochemical expressionof sodium-dependent glucose transporter - 2 (SGLT-2) in clear cell renal carcinoma: possible prognostic implications.

PURPOSE: Glucose is a major energy resource for tumor cell survival and growth, and its influx into cells is mainly carried out by facilitative glucose transporters (GLUTs). Sodium - dependent glucose transporters (SGLTs) have been highlighted as playing important roles in diabetic treatment. However, their potential roles in cancer remain unclear. We examined expression patterns of SGLTs in tumor tissues together with conventional pathological variables to determine prognostic significance in patients with renal cell carcinoma (RCC). MATERIALS AND METHODS: Nephrectomy specimens were obtained from 68 patients. GLUT - 1, - 2 and SGLT - 1, - 2 expression in tumor and adjacent normal tissues were analyzed by immunohistochemical staining, and intensity was quantified using an image analyzer. RESULTS: The four glucose transporters evaluated were broadly distributed in tumor tissues as well as throughout the normal parenchyma. There was no significant correlation between transporter expression and conventional pathological variables. However, increased SGLT - 2 expression was significantly associated with shorter overall survival (p < 0.01), regardless of metastatic status. CONCLUSIONS: We propose possible prognostic significance of SGLT - 2 expression in human RCC. Given that glucose is a major energy resource for tumor cells and that glucose transport is largely mediated by SGLT, SGLT - 2 may serve as a possible therapeutic target in RCC.

Enhancing immune effects of a DNA vaccine against kidney cancer using CD40L as an adjuvant

The use of specific combinations of antigens and adjuvant represents a promising approach for increasing the immunogenicity of DNA vaccines. In the present study, we evaluated the immunity and antitumor effects of DNA vaccines with G250 as the target antigen in a mouse model of renal cell carcinoma. We constructed two recombinant plasmids, pVAX1-G250 and pVAX1-CD40L. The recombinant plasmids were injected into mice by intramuscular injection and electrical pulse stimulation. ELISA and ELISPOT experiments were performed to evaluate the corresponding humoral and cellular immune responses following immunization. To further investigate the antitumor potential of the DNA vaccines, we established a tumor-bearing mouse model expressing G250 target antigen. Our results showed that immunization with the combination of the two plasmids exerted the strongest anti-tumor effects. Therefore, our findings demonstrated the effectiveness of CD40L as an adjuvant for DNA vaccines and highlighted the promising use of these vaccines for the treatment of tumors.

Oncogene miR-154-5p regulates cellular function and acts as a molecular marker with poor prognosis in renal cell carcinoma.

AIMS: In adult population, the renal cell carcinoma (RCC) is one of the most common urological malignancies. It is meaningful to research for the molecular markers which are involved in the occurrence and development of RCC. Therefore, we concentrate on illuminating the role of microRNA-154-5p in progression of RCC and explore its prognostic values. MAIN METHODS: The real-time quantitative polymerase chain reaction (RT-qPCR) was applied to determine expression level of miR-154-5p in tissues. Afterwards, the transfected cell lines ACHN and 786-O were used for the CCK-8 assay, MTT assay, wound healing assay, transwell assay and flow cytometric assay to explore the role of miR-154-5p in regulating cellular function. In addition, formalin-fixed paraffin-embedded (FFPE) renal cancer samples were used for detecting the relationship between expression level of miR-154-5p and clinical information. Furthermore, univariate and multivariate Cox proportional-hazards regression analyses, and the Kaplan-Meier survival curves were performed to evaluate the prognostic value of miR-154-5p in RCC. KEY FINDINGS: The RT-qPCR indicated that miR-154-5p is up-regulated in RCC pathologic specimens and cell lines. Results of study also demonstrated that upregulation of miR-154-5p reduced cell apoptosis and promoted cell proliferation, viability, migration as well as invasion in RCC cells. The prognosis analyses indicated that the expression level of miR-154-5p is associated with the prognosis of renal cancer, and the overall survival of patients with low expression is longer. SIGNIFICANCE: The present study revealed that the oncogene miR-154-5p regulates cellular function and acts as a molecular marker with poor prognosis in renal cell carcinoma.

Inhibition of eIF4E cooperates with chemotherapy and immunotherapy in renal cell carcinoma.

PURPOSE: Although overexpression of the eukaryotic translation initiation factor 4E (eIF4E) is detected in patients with renal cell carcinoma (RCC) and associated with poor prognosis, the possible roles of eIF4E in RCC have not been revealed. METHODS: The effects of eIF4E inhibition on cell growth, migration, survival, chemo-/immunotherapy and eIF4E pathways via pharmacological inhibitor and genetic siRNA knockdown were analyzed in RCC cells. RESULTS: In this work, we demonstrate that eIF4E is critically involved in multiple biological functions of RCC. We firstly inhibited eIF4E activity by ribavirin in two cell lines (Caki-1 and ACHN) representing RCC metastasis models. We demonstrated that ribavirin inhibited proliferation and migration and induced apoptosis in RCC in a dose-dependent manner. We further confirmed that the inhibitory effects of ribavirin were attributed to its ability in inhibiting eIF4E-regulated protein translation and activity. eIF4E inhibition using siRNA knockdown mimicked ribavirin's effector in RCC cells. Importantly, eIF4E inhibition by both ribavirin and siRNA knockdown significantly sensitized RCC response to chemo- and immunotherapeutic agents in vitro as well as in vivo. CONCLUSIONS: Our findings clearly demonstrate the roles of eIF4E in RCC growth, survival, metastasis and resistance. Ribavirin is an antiviral drug, and its clinical efficacy is currently being investigated in the treatment of various cancers. Our findings support and provide a preclinical evidence for clinical trial for the combination of ribavirin with chemo-/immunotherapy in RCC.