Behavior Of Renal Cell Carcinoma Research Articles

LncRNA AGAP2 antisense RNA 1 stabilized by insulin-like growth factor 2 mRNA binding protein 3 promotes macrophage M2 polarization in clear cell renal cell carcinoma through regulation of the microRNA-9-5p/THBS2/PI3K-Akt pathway

BackgroundIncreasing evidence highlights the potential role of long non-coding RNAs (lncRNAs) in the biological behaviors of renal cell carcinoma (RCC). Here, we explored the mechanism of AGAP2-AS1 in the occurrence and development of clear cell RCC (ccRCC) involving IGF2BP3/miR-9-5p/THBS2.MethodsThe expressions of AGAP2-AS1, IGF2BP3, miR-9-5p, and THBS2 and their relationship were analyzed by bioinformatics. The targeting relationship between AGAP2-AS1 and miR-9-5p and between miR-9-5p and THBS2 was evaluated with their effect on cell biological behaviors and macrophage polarization assayed. Finally, we tested the effect of AGAP2-AS1 on ccRCC tumor formation in xenograft tumors.ResultsIGF2BP3 could stabilize AGAP2-AS1 through m6A modification. AGAP2-AS1 was highly expressed in ccRCC tissues and cells. The lentivirus-mediated intervention of AGAP2-AS1 induced malignant behaviors of ccRCC cells and led to M2 polarization of macrophages. In addition, THBS2 promoted M2 polarization of macrophages by activating the PI3K/AKT signaling pathway. AGAP2-AS1 could directly bind with miR-9-5p and promote the expression of THBS2 downstream of miR-9-5p. These results were further verified by in vivo experiments.ConclusionAGAP2-AS1 stabilized by IGF2BP3 competitively binds to miR-9-5p to up-regulate THBS2, activating the PI3K/AKT signaling pathway and inducing macrophage M2 polarization, thus facilitating the development of RCC.

Hsa_circ_0003596, as a novel oncogene, regulates the malignant behavior of renal cell carcinoma by modulating glycolysis

BackgroundThis research was planned to analyze hsa_circ_0003596 (circCOL5A1) and glycolysis-focused mechanisms in renal cell carcinoma (RCC).MethodscircCOL5A1, miR-370-5p, and PRKCSH levels were determined in RCC tissues and selected cell lines by RT-qPCR and/or Western blot. RCC cells after corresponding transfection were tested by colony formation assay, EdU assay, Transwell assay, and flow cytometry to analyze cell proliferation, invasion, migration, and apoptosis. Meanwhile, glycolysis in cells was evaluated by measuring glucose consumption, lactic acid, and ATP production, as well as immunoblotting for HK2 and PKM2. In addition, circCOL5A1 knockdown was performed in animal experiments to observe tumor growth and glycolysis. Finally, the ceRNA network between circCOL5A1, miR-370-5p, and PRKCSH was studied by luciferase reporter assay and RIP experiment.ResultscircCOL5A1 and PRKCSH were highly expressed and miR-370-5p was poorly expressed in RCC. circCOL5A1 knockdown depressed RCC proliferation, invasion, migration, and glycolysis, and enhanced apoptosis. circCOL5A1 competitively adsorbed miR-370-5p. Artificial upregulation of miR-370-5p saved the pro-tumor effect of circCOL5A1 on RCC cells, as evidenced by suppression of tumor malignancy and glycolysis. miR-370-5p targeted PRKCSH. PRKCSH overexpression contributed to a reversal of the anti-tumor effect of circCOL5A1 silencing. Silencing circCOL5A1 inhibited RCC tumor growth and glycolysis.ConclusionscircCOL5A1 regulates the malignant behavior of RCC by modulating glycolysis.

Expresión de PD-L1 en cáncer renal, características pronósticas y utilidad en la práctica clínica habitual

IntroductionThe expression of PD-L1 in renal cell carcinoma (RCC) is associated with worse survival and prognostic clinical-pathological features. However, they seem to respond better to new therapeutic agents. Knowing the behavior of RCC according to the presence of PD-L1 may have implications for medical counseling and therapeutic approaches. ObjectiveTo identify the presence of PD-L1 in renal tumor cells and analyze its association with patientś prognostic factors, overall survival (OS) and cancer-specific survival (CSS). MethodologyRetrospective analysis of RCC tissue samples, obtained between 2018 and 2021. Immunohistochemistry analysis with mouse monoclonal Anti PD-L1, clone 22C3. Definition of PD-L1 “positive” as a Tumor Proportion Score ≥ 1%. Comparison of prognostic factors according to the presence or absence of PD-L1, and univariate analysis for OS and CSS. Results14% (n=11) of the sample were PD-L1(+). Average age was 59 years. There were no statistically significant differences between PD-L1 status and TNM stages, nuclear grade and histology. PD-L1(+) had worse OS with a HR of 5.27 (CI: 1.1-23.7; p=0.03) and CSS showed a unfavorable tendency for PD-L1(+) with a HR of 4.79 (CI: 0.79-28.95; p=0.08). ConclusionThe prevalence of PD-L1 in RCC is considerable. In this study PD-L1(+) was associated with unfavorable OS and CSS. It seems reasonable to incorporate its routine use in RCC.

Expression of PD-L1 in renal cancer, prognostic features and clinical utility of its routine staining

IntroductionThe expression of PD-L1 in renal cell carcinoma (RCC) is associated with worse survival and prognostic clinical-pathological features. However, they seem to respond better to new therapeutic agents. Knowing the behavior of RCC according to the presence of PD-L1 has implications for medical counseling and therapeutic approaches. ObjectiveTo identify the presence of PD-L1 in renal tumor cells and analyze its association with patients’ prognostic factors, overall survival (OS) and cancer-specific survival (CSS). MethodologyRetrospective analysis of RCC tissue samples, obtained between 2018 and 2021. Immunohistochemistry analysis with mouse monoclonal Anti PD-L1, clone 22C3. Definition of PD-L1 “positive” as a Tumor Proportion Score ≥1%. Comparison of prognostic factors according to the presence or absence of PD-L1, and univariate analysis for OS and CSS. Results14% (n = 11) of the sample were PD-L1(+). Average age was 59 years. There were no statistically significant differences between PD-L1 status and TNM stages, nuclear grade and histology. PD-L1(+) had worse OS with a HR of 5.27 (CI: 1.1–23.7; P = .03) and CSS showed a unfavorable tendency for PD-L1(+) with a HR of 4.79 (CI: 0.79–28.95; P = .08). ConclusionThe prevalence of PD-L1 in RCC is considerable. In this study PD-L1(+) was associated with unfavorable OS and CSS. It seems reasonable to incorporate its routine use in RCC.

Association between decreased ipsilateral renal function and aggressive behavior in renal cell carcinoma

BackgroundTo assess prognostic value of pre-operative ipsilateral split renal function (SRF) on disease-free survival (DFS) and its association with aggressive pathological features in renal cell carcinoma (RCC) patients. MethodsWe examined patients registered in SNUG-RCC-Nx who underwent partial or radical nephrectomy at Seoul National University Hospital between January 1, 2010 and December 31, 2020. Patients with the following criteria were excluded from the study. 1) non-kidney origin cancer or benign renal tumor, 2) no pre-operative Tc 99 m-DTPA renal scan, 3) single kidney status or previous partial or radical nephrectomy, and 4) bilateral renal mass. Finally, 1,078 patients were included.ResultsAmong 1,078 patients, 899 (83.4%) showed maintained ipsilateral SRF on DTPA renal scan; 179 patients (16.6%) showed decreased SRF. The decreased SRF group showed significantly large tumor size (maintained vs. decreased SRF; 3.31 ± 2.15 vs. 6.85 ± 3.25, p < 0.001), high Fuhrman grade (grade 3–4) (41.7% vs. 55.6%, p < 0.001), and high T stage (T stage 3–4) (9.0% vs. 20.1%, p < 0.001). Pathological invasive features, including invasion of the renal capsule, perirenal fat, renal sinus fat, vein, and collecting duct system, were associated with low SRF of the ipsilateral kidney. Univariate Cox regression analysis identified higher SSIGN (The stage, size, grade, and necrosis) score and decreased ipsilateral SRF as significant risk factors, while multivariate analysis showed SSIGN (5–7) (hazard ratio [HR] 11.9, p < 0.001) and SSIGN (8–10) (HR 69.2, p < 0.001) were significantly associated with shortened DFS, while decreased ipsilateral SRF (HR 1.75, p = 0.065) showed borderline significance. Kaplan–Meier analysis showed that decreased ipsilateral SRF (< 45%) group had shorter DFS than the other group (median DFS: 90.3 months vs. not reached, p < 0.001).ConclusionsAmong unilateral RCC patients, those with low ipsilateral SRF showed poor prognosis with pathologically invasive features. Our novel approach may facilitate risk stratification in RCC patients, helping formulate a treatment strategy.

Effect of AKT silence on malignant biological behavior of renal cell carcinoma cells

BackgroundAs the most common malignant tumor of primary renal tumor, renal cell carcinoma (RCC) is the highly invasive disease with high mortality. AKT is a serine/threonine kinase that play a critical role in the phosphoinositide 3-kinase (PI3K) signaling pathway, and it is an attractive target for RCC treatment. The aim of present study was to investigate the effect of AKT silence on malignant behavior of renal cell carcinoma cells.MethodsAKT expression was quantified by immunohistochemistry in tumor tissues and normal tissues. The human RCC cell lines Caki-2 cell were chosen for this study. The optimal silencing siRNA was subsequently selected by RT-qPCR and western blot. The effect of AKT silence on RCC cells was investigated by CCK8 assay, transwell assay, scratch test and flow cytometry. The AKT1 expression in human renal cell carcinoma tissue was detected by immunohistochemical staining.ResultsThe AKT in Caki-2 cells was silenced successfully. The results shown AKT silence could inhibit cell proliferation, invasion, and, migration. In addition, AKT silence could promote Caki-2 cell apoptosis with prevention of RCC cells move from G1 phase to S phase. Immunohistochemical staining revealed significant difference of expression of AKT1 in RCC tissues and normal renal tissues. Taken together, AKT family members might involve in malignant growth of RCC, and might be a potential therapeutic target.ConclusionOur data show that AKT silence inhibited cell proliferation, invasion, and, migration of Caki-2 cell, and promoted Caki-2 cell apoptosis. Moreover, AKT silence prevented RCC cells move from G1 phase to S phase. Therefore, AKT may act as an effective therapeutic target for RCC.

The miRNA-21-5p Payload in Exosomes from M2 Macrophages Drives Tumor Cell Aggression via PTEN/Akt Signaling in Renal Cell Carcinoma.

M2 macrophages in the tumor microenvironment are important drivers of cancer metastasis. Exosomes play a critical role in the crosstalk between different cells by delivering microRNAs or other cargos. Whether exosomes derived from pro-tumorigenic M2 macrophages (M2-Exos) could modulate the metastatic behavior of renal cell carcinoma (RCC) is unclear. This study found that M2-Exos promotes migration and invasion in RCC cells. Inhibiting miR-21-5p in M2-Exos significantly reversed their pro-metastatic effects on RCC cells in vitro and in the avian embryo chorioallantoic membrane in vivo tumor model. We further found that the pro-metastatic mechanism of miR-21-5p in M2-Exos is by targeting PTEN-3′UTR to regulate PTEN/Akt signaling. Taken together, our results demonstrate that M2-Exos carries miR-21-5p promote metastatic features of RCC cells through PTEN/Akt signaling. Reversing this could serve as a novel approach to control RCC metastasis.

The role of Wnt/β-catenin/TCF-4 pathway on biological behavior of renal cell carcinoma and its mechanism

Objective: To investigate the role of Wnt/β-catenin/TCF-4 pathway in renal cancer cells and to analyze its possible mechanism. Methods: β-catenin and TCF-4 were inhibited by siRNA in 786-O cells. The proliferation of transfected cells was detected by CCK8. The cell death of transfected cells was detected by acridine orange -ethidium bromide staining. The expressions of TCF-4, bcl-2, bax and Caspase-3 were detected in transfection group, empty vector group and negative control groups by western blot. Results: The cell proliferation ability of the β-catenin transfection group was significantly lower than that of the control group (0.443±0.145 vs 0.910±0.721), meanwhile, the cell death rate was significantly increased (16.38±5.32 vs 6.61±1.04), the expression level of Caspase 3 and bax was increased, and the expression of anti-apoptotic protein Bcl-2 was decreased. Decreased TCF-4 led to the same results as inhibition of β-catenin (all P<0.05). Conclusion: The Wnt/β-catenin/TCF-4 pathway may play a role in the regulation of proliferation and apoptosis in 786-O renal cancer cells. The mechanism might through regulating of the downstream apoptosis proteins Caspase 3, bax and anti-apoptotic protein Bcl-2.

Establishment of cohesion 1 homolog 2 facilitates cell aggressive behaviors and induces poor prognosis in renal cell carcinoma.

Background and aimsEstablishment of cohesion 1 homolog 2 (ESCO2) has been identified as an essential factor for cohesion in cell cycle in human multiple cancers. Nonetheless, its functional implication on prognosis and cellular behaviors of renal cell carcinoma (RCC) is rarely elucidated. We performed this study to detect the effects of ESCO2 in RCC progression.MethodsWe accessed The Cancer Genome Atlas (TCGA) database to evaluate the ESCO2 expression levels in tumor tissues, including 32 normal tissues and 289 tumor tissues. Quantitative real‐time PCR and Western blot were implemented for expression detection. After ESCO2 knockdown using siRNAs interference, functional experiments were conducted to explore the role of ESCO2, such as cell proliferation analysis and colony formation assay. Transwell assays for migration and invasion was also performed.ResultsIn this study, ESCO2 was significantly increased in RCC tissues and cell lines. The RCC patients with high expression of ESCO2 were susceptible to unfavorable prognosis, and its expression has a marked association with clinical features containing age, gender, pathologic stage, and so on. Furthermore, knockdown of ESCO2 inhibited cell growth, invasion, and migration. Mechanistically, phosphorylation protein kinase B (AKT) and mammalian target of rapamycin (mTOR), proliferating cell nuclear antigen (PCNA), and p53 were all down‐regulated due to the ESCO2 inhibition.ConclusionsTherefore, our results raised the possibility that ESCO2 may act as a promising option for tumor therapeutic interference by exhibiting enhanced selectivity over conventional chemotherapy.

Long Noncoding RNA LINC01133 Promotes the Malignant Behaviors of Renal Cell Carcinoma by Regulating the miR-30b-5p/Rab3D Axis

Renal cell carcinoma (RCC) is the most common type of kidney cancer with rising incidence. Long noncoding RNA (lncRNA) LINC01133 is a novel lncRNA that is involved in the development of several types of cancers. However, the role of LINC01133 in RCC has not been reported. Thus, in this study, we investigated the functions of LINC01133 in RCC. The qualitative real-time polymerase chain reaction analysis was performed to examine the levels of LINC01133 in RCC tissues and adjacent tissues, as well as RCC cell lines. The results showed that LINC01133 was highly expressed in RCC tissue specimens and cell lines. Downregulation of LINC01133 significantly inhibited the proliferation, migration, and invasion of RCC cells. Further mechanistic investigations proved that LINC01133 directly interacted with microRNA (miR)-30b-5p and regulated the miR-30b-5p expression in RCC cell lines. Moreover, miR-30b-5p exhibited tumor-suppressive activity in RCC cell lines, which was mediated by targeting Ras-related protein Rab-3D (Rab3D). In vivo study showed that LINC01133 knockdown suppressed tumor growth in the nude mice. Taken together, these findings indicated that LINC01133 might be an oncogene in RCC through regulation of the miR-30b-5p/Rab3D axis. Thus, LINC01133 might serve as a potential therapeutic target for the treatment of RCC.

Upregulated expression of eIF3C is associated with malignant behavior in renal cell carcinoma.

Eukaryotic initiation factor 3c (eIF3C) is involved in the initiation of protein translation. Aberrant eIF3C expression has been reported in different types of human cancer. The present study aimed to assess the role of eIF3C in the malignant behavior of renal cell carcinoma invitro and invivo. eIF3C expression was assessed in 16 pairs of renal cell carcinoma (RCC) and matched distant normal tissues, and in RCC cell lines using immunohistochemistry. Subsequently, eIF3C was depleted using lentiviral short hairpin RNA and cell proliferation, cell cycle distribution and apoptosis of these eIF3C‑depleted cells were examined. Additionally, tumor cell xenograft assays in nude mice, Affymetrix microarrays and ingenuity pathway analyses were performed. eIF3C expression was upregulated in RCC tissues and cell lines. Depletion of eIF3C reduced tumor cell proliferation and arrested them at the G1 stage, thus promoting their apoptosis invitro. Depletion of eIF3C also inhibited the formation and growth of tumor cell xenografts in nude mice. In addition, depletion of eIF3C altered the expression levels of 994 differentially expressed genes in RCC cells (516 genes were upregulated and 478genes were downregulated). The expression levels of phosphorylated‑AKT, c‑JUN and NFKB inhibitor α were lower in the shorth hairpin RNA eIF3C‑transfected RCC cells compared with in the control group. In conclusion, the present study demonstrated that upregulated eIF3C expression contributed to the development and progression of RCC. Future studies should further evaluate whether eIF3C could be used as a potential strategy for RCC targeting therapy.

Research progress of long non-coding RNA in renal cell carcinoma metastasis

Metastasis is one of the important biological behaviors of renal cell carcinoma. As a non-coding RNA transcript, long non-coding RNA (lncRNA) plays an important role in the process of replication, transcription and translation of cellular genetic material, and has great effects in the metastasis mechanism of renal cell carcinoma. This article reviews the mechanism of lncRNA involvement in renal cell carcinoma metastasis. Key words: Long non-coding RNA; Renal cell carcinoma; Metastasis

Effect of long-chain noncoding RNA NEAT1 on the proliferation and invasion of renal cell carcinoma

Objective To observe the expression of long non-coding RNA (LncRNA-NEAT1) in renal cell carcinoma and cell lines, and to explore its influence on the malignant biological behavior of renal cell carcinoma and its possible molecular mechanism. Methods The expression of NEAT1 was detected by quantitative polymerase chain reaction (qPCR) in 10 cases of renal cell carcinoma and paracancerous tissues, and in 4 types of renal cell carcinoma cells and normal renal tubular epithelial cells. ACHN cells infected with negative control lentivirus (LV-NC) were used as control group, and ACHN cells infected with recombinant lentivirus carrying NEAT1 gene (LV-NEAT1) were used as experimental group. Bioinformatics predicts targeted miRNA and downstream genes of NEAT1. The effect of overexpression of NEAT1 on the mRNA expression of miR-342-3p and cell adhesion molecule 1 (CADM1) was detected by qPCR. The protein expression of CADM1 was detected by Western blot. The proliferation and invasion of ACHN cells were detected by methyl thiazolyl tetrazolium (MTT) method and Transwell invasion assay. Results The expression level of NEAT1 in renal cell carcinoma was lower than that in paracancerous tissue (P<0.01). The expression of NEAT1 in renal carcinoma cell lines was lower than that in renal tubular epithelial cells (P<0.01). After LV-NEAT1 infection, the expression of NEAT1 and CADM1 gene were significantly increased (P<0.01), while the expression of miR-342-3p decreased (P<0.01). Overexpression of NEAT1 significantly inhibited cell proliferation and invasion of ACHN cells (P<0.05). Conclusions LncRNA NEAT1 was down-regulated in renal cell carcinoma and cell lines. Overexpression of NEAT1 inhibited the proliferation and invasion of ACHN cells. The molecular mechanism may be that NEAT1 up-regulates the expression of CADM1 gene through complementary binding to miR-342-3p. Key words: RNA, long noncoding; Kidney neoplasms; Cell proliferation; Neoplasm invasiveness; In vitro

Pathological significance and prognostic roles of densities of CD57+ cells, CD68+ cells, and mast cells, and their ratios in clear cell renal cell carcinoma

The immune system is closely associated with malignant behavior in renal cell carcinoma (RCC). Therefore, understanding the pathological roles of immune cells in tumor stroma is essential to discuss the pathological characteristics of RCC. In this study, the clinical significance of densities of CD57+ cells, CD68+ cells, and mast cells, and their ratios were investigated in patients with clear cell RCC. The densities of CD57+, CD68+, and mast cells were evaluated by immunohistochemical techniques in 179 patients. Proliferation index, apoptotic index, and microvessel density were evaluated by using anti-Ki-67, anti-cleaved caspase-3, and anti-CD31 antibodies, respectively. The density of CD57+ cell was negatively correlated with grade, pT stage, and metastasis, although densities of CD68+ cell and mast cell were positively correlated. Ratios of CD68+ cell/CD57+ cell and mast cell/CD57+ cell were significantly correlated with grade, pT stage, and metastasis. Survival analyses showed that the CD68+ cell/CD57+ cell ratio was a significant predictor for cause-specific survival by multivariate analyses (hazard ratio = 1.41, 95% confidence interval = 1.03-1.93, P = .031) and was significantly correlated with proliferation index, apoptotic index, and microvessel density (r = .47, P <. 001; r = -.31, P < .001; and r = .40, P < .001, respectively). In conclusion, CD57+ cells, CD68+ cells, and mast cells played important roles in malignancy in clear cell RCC. The CD68+ cell/CD57+ cell ratio was strongly correlated with pathological features and prognosis in these patients because this ratio reflected the status of cancer cell proliferation, apoptosis, and angiogenesis.

Outcomes of Patients With Late-Relapse Metastatic Renal Cell Carcinoma Treated With Targeted Therapies: A Single Institution Experience.

Late relapse with presentation of metastatic disease >5 years after nephrectomy with curative intent is a known behavior of renal cell carcinoma (RCC), but data on outcomes, especially regarding targeted therapies, are limited. In this study, we analyze clinicopathologic features and response to targeted therapy in patients with late-relapse metastatic RCC (mRCC). We retrospectively reviewed clinical data on consecutive patients treated with targeted therapy for mRCC diagnosed >5 years after nephrectomy with curative intent. A total of 24 patients (100% clear cell histology, median age 72 years, 83% males, all with prior nephrectomies) met inclusion criteria; 71% had favorable risk, and 25% had intermediate risk by International Metastatic Renal Cell Carcinoma Database Consortium criteria. The estimated median overall survival for all patients was 60.5 months, and the 3-year overall survival rate was 71.78% (95% confidence interval, 47.98%-84.77%). All patients were treated with targeted therapy; first-line treatments included pazopanib (46%), sorafenib (25%), sunitinib (17%), and cytokine (13%), with no significant difference in time to treatment failure between therapies. Median time on first-line therapy was 19.7 months; 67% of patients received second-line treatment. Metastases were detected at considerable rates in sites considered historically uncommon, such as the pancreas, adrenal glands, and soft tissue. Patients with late-relapse mRCC treated with targeted therapy had prolonged survival that compared favorably to historical controls, and metastases in uncommon sites were noted.

Clinical significance and expression of PUMA, MCL-1, and p53 in human renal cell carcinoma and para-carcinoma tissues.

We investigated the expression level of p53 upregulated modulator of apoptosis (PUMA), myeloid cell leukemia-I (MCL-1), and p53 in renal cell carcinoma (RCC) and para-carcinoma tissues, as well as their clinical significance. The expression levels of PUMA, MCL-1, and p53 in RCC and para-carcinoma tissues were measured using immunohistochemical and quantitative real-time PCR methods. Correlations between protein expression and pathological characteristics were analyzed. Renal clear cell carcinoma showed elevated MCL-1 and p53 protein expression (P > 0.05) and reduced PUMA expression as compared to that in para-carcinoma tissues. Spearman ranking correlation analysis showed that expression of PUMA, MCL-1, and p53 in was negatively correlated with RCC (r = -0.504, P = 0.001; r = -0.413, P = 0.008). We also observed significant correlation between MCL-1 expression and tumor differentiation (P < 0.05), where MCL-1 expression was significantly higher in well-differentiated adenocarcinoma as compared to that in medium or lowly differentiated adenocarcinoma. In addition, p53 expression was highly correlated with TNM staging (P < 0.05). Single factor analysis on COX's proportional hazard model indicated that postoperative survival rate and prognosis of renal clear cell carcinoma was highly correlated with TNM staging (P < 0.05). Quantitative real-time PCR analysis indicated higher expression of PUMA, MCL-1, and p53 in cancer tissues as compared to that in para-carcinoma tissues (P < 0.05).The expression of PUMA, MCL-1, and p53 can reflect the biological behavior of renal cell carcinoma, and can be used to indicate tumor invasion, progression, and prognosis.

Role of Computed Tomography in the Pre operative Diagnosis of Clear Cell Renal Carcinoma

Background: Renal cell carcinoma (RCC) accounts for 3% of all human malignant tumors. The behavior of RCC apparently depends on its subtype. CT scan can provide detailed information about the tumor itself and regarding its precise extension. The pre-histological diagnosis of clear cell renal carcinoma could be made with more precision on the basis of CT scan features and would ultimately play a major role in the prognosis and management of the disease. Objective: To determine the diagnostic accuracy of computed tomography in the diagnosis of clear cell renal carcinoma taking histopathological findings as gold standard. Methods: Total 100 patients had renal mass were included. All patients underwent contrast enhanced CT scan. On the basis of CT scan features a pre-surgical diagnosis of histological subtype of RCC, clear cell renal carcinoma was made. The patients were followed by nephrectomy. The diagnostic accuracy of CT scan was determined. Results: The male to female ratio was 3.2:1.0. Out of total study subjects 85.0% patients turned out to be renal cell carcinomas and among these 40 (47%) were right sided and 45 (53%) were left sided. The mean size of tumor was 12.75 cm. The sensitivity, specificity, and diagnostic accuracy of CT scan were 89.0%, 72.7%, and 86.0% respectively. Conclusion: The CT scan was helpful in diagnosing clear cell renal carcinoma. The most valuable parameter was the degree of enhancement of clear cell renal carcinoma with other parameters playing supplemental role.

VHL protein expression in renal cell carcinoma

Introduction: Various studies have been performed to detect VHL gene mutation in renal cell carcinoma (RCCs) but there is paucity of literature analyzing VHL expression at the protein level. Present study was carried out to analyze VHL protein (pVHL) expression in the tissue of RCCs and its correlation with tumor grade & stage. Material and methods: Immunohistochemical detection of pVHL was done by using a mouse monoclonal antibody raised against amino acids 54-213 of VHL of human. Statistical analysis was done by using chi-square test and Kruskall Wallis H Test. Results: 32 patients of renal cell carcinoma were included in the study. pVHL expression was positive in 84.40% cases . Among all pVHL positive cases, combined cytoplasmic and nuclear expression of pVHL was most common (59.0%). Exclusive nuclear expression alone was rare and was noted in only one case. Chromophobe RCC (1 case) was negative for p VHL. Exclusive cytoplasmic pVHL expression was more frequently noticed in low grade tumors. Conclusion: VHL protein expression and its cytoplasmic and nuclear distribution is of potential relevance for the diagnosis and biological behavior of RCCs. Combined nuclear and cytoplasmic expression of VHL protein is more frequently seen in low grade and early stage of renal cell carcinomas.

The effects of RNA interference mediated VEGF gene silencing on biological behavior of renal cell carcinoma and transplanted renal tumor in nude mice

This study was to explore the effects of RNA interference mediated vascular endothelial growth factor (VEGF) gene silencing on biological behavior of renal cell carcinoma (RCC), transplanted renal tumor and angiogenesis in nude mice. The specific siRNA sequence targeting VEGF were designed and synthesized to construct hVEGF-siRNA plasmid which was transfected into RCC 786-O cells. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for the detection of VEGF gene expression and western blot was adopted for the examination of VEGF protein expression. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect cell growth as well as cell migration and invasion. The transplanted renal tumor models in nude mice were established, and the growth condition of nude mice, and VEGF protein expression in transplanted tumor slices and the microvessel density (MVD) were detected. The expression level of VEGF mRNA in VEGF-siRNA group was significant lower than that in the control group and negative group, suggesting that establishment of plasmid specifically inhibited the expression of VEGF gene The expression level of VEGF protein in VEGF-siRNA group was significant lower than that in the control group and negative group. VEGF gene silencing has the significant inhibition effects on proliferation, migration and invasion of RCC 786-O cells. The tumor weight, VEGF protein positive rate and MVD in VEGF-siRNA group were significant lower than those in negative group and blank group. The VEGF gene silencing could inhibit the cell proliferation, migration and invasion of RCC 786-O cells; inhibition of VEGF protein expression could prevent transplanted RCC growth and tumor angiogenesis.

Very late relapse metastatic renal cell carcinoma: Characteristics and outcomes of patients with a disease-free interval of greater than 10 years.

541 Background: Late relapse of renal cell carcinoma (RCC), or presentation with metastatic disease after a disease free interval of &gt;5 years, is a known behavior of RCC. Recent studies have concluded that late relapse RCC is associated with favorable patient and tumor characteristics as well as an improved response to targeted therapy (TT) when compared to early relapse patients. Less studied are patients who relapse very late, with a disease free interval &gt;10 years. We evaluated the clinical characteristics, response to TT and outcomes of this unique population. Methods: We collected data on consecutive patients with metastatic RCC who had disease recurrence &gt;10 years after nephrectomy. Outcomes were tabulated using basic statistical techniques; adverse events were graded using CTCAE v4.0 and treatment response graded using RECIST 1.1. Results: Among 720 RCC patients treated with nephrectomy, we identified 8 who developed recurrent metastatic disease after a &gt;10 year disease free interval (median: 16.7 years; range: 11.7-29.0). All patients presented with clear cell histology; 88% favorable IMDC and MSKCC risk subgroups. All patients presented with multiple metastases, with the most common sites being lung and bone, while unusual sites such as soft tissue, pancreas and adrenal were also detected. Median time on first-line TT was 20.1 months; 4, 3 and 1 patient received pazopanib (best response: PR), sunitinib (best response: SD) and cytokine (best response: PD) as first-line therapy, respectively. The median number of sequential TT received was 2 (range: 1-4). Four patients died, median OS was 46.6 months (range: 9.8-129), 3 year OS rate was 63%. Common adverse events to TT were fatigue (88%), anorexia (38%) and diarrhea (50%), 94% grade 1/2. Conclusions: Patients are at life-long risk of recurrence after resection of localized RCC as it is possible for metastases to present &gt;10 years after resection. Patients in our study had relatively large metastatic burden and a wide distribution of metastatic sites, insights that may be useful clinically during surveillance. Our cohort demonstrated favorable prognostic features and outcomes when compared to historical controls.