Curcumin Inhibits Proliferation of Renal Cell Carcinoma in vitro and in vivo by Regulating miR-148/ADAMTS18 through Suppressing Autophagy / 中国结合医学杂志

OBJECTIVE@#To explore the effect of curcumin on the proliferation of renal cell carcinoma and analyze its regulation mechanism.@*METHODS@#In RCC cell lines of A498 and 786-O, the effects of curcumin (2.5, 5, 10 µ mo/L) on the proliferation were analyzed by Annexin V+PI staining. Besides, A498 was inoculated into nude mice to establish tumorigenic models, and the model mice were treated with different concentrations of curcumin (100, 200, and 400 mg/kg), once daily for 30 days. Then the tumor diameter was measured, the tumor cells were observed by hematoxylin-eosin staining, and the protein expressions of miR-148 and ADAMTS18 were detected by immunohistochemistry. In vitro, after transfection of miR-148 mimics, miR-148 inhibitor or si-ADAMTS18 in cell lines, the expression of ADAMTS18 was examined by Western blotting and the cell survival rate was analyzed using MTT. Subsequently, Western blot analysis was again used to examine the autophagy phenomenon by measuring the relative expression level of LC3-II/LC3-I; autophagy-associated genes, including those of Beclin-1 and ATG5, were also examined when miR-148 was silenced in both cell lines with curcumin treatment.@*RESULTS@#Curcumin could inhibit the proliferation of RCC in cell lines and nude mice. The expression of miR-148 and ADAMTS18 was upregulated after curcumin treatment both in vitro and in vivo (P<0.05). The cell survival rate was dramatically declined upon miR-148 or ADAMTS18 upregulated. However, si-ADAMTS18 treatment or miR-148 inhibitor reversed these results, that is, both of them promoted the cell survival rate.@*CONCLUSION@#Curcumin can inhibit the proliferation of renal cell carcinoma by regulating the miR-148/ ADAMTS18 axis through the suppression of autophagy in vitro and in vivo. There may exist a positive feedback loop between miR-148 and ADAMTS18 gene in RCC.

Mechanism of nuclear protein 1 in the resistance to axitinib in clear cell renal cell carcinoma / 北京大学学报(医学版)

OBJECTIVE@#To explore the potential mechanism of resistance to axitinib in clear cell renal cell carcinoma (ccRCC), with a view to expanding the understanding of axitinib resistance, facilitating the design of more specific treatment options, and improving the treatment effectiveness and survival prognosis of patients.@*METHODS@#By exploring the half maximum inhibitory concentration (IC50) of axitinib on ccRCC cell lines 786-O and Caki-1, cell lines resistant to axitinib were constructed by repeatedly stimulated with axitinib at this concentration for 30 cycles in vitro. Cell lines that were not treated by axitinib were sensitive cell lines. The phenotypic differences of cell proliferation and apoptosis levels between drug resistant and sensitive lines were tested. Genes that might be involved in the drug resistance process were screened from the differentially expressed genes that were co-upregulated in the two drug resistant lines by transcriptome sequencing. The expression level of the target gene in the drug resistant lines was verified by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB). The expression differences of the target gene in ccRCC tumor tissues and adjacent tissues were analyzed in the Gene Expression Profiling Interactive Analysis (GEPIA) public database, and the impact of the target gene on the prognosis of ccRCC patients was analyzed in the Kaplan-Meier Plotter (K-M Plotter) database. After knocking down the target gene in the drug resistant lines using RNA interference by lentivirus vector, the phenotypic differences of the cell lines were tested again. WB was used to detect the levels of apoptosis-related proteins in the different treated cell lines to find molecular pathways that might lead to drug resistance.@*RESULTS@#Cell lines 786-O-R and Caki-1-R resistant to axitinib were successfully constructed in vitro, and their IC50 were significantly higher than those of the sensitive cell lines (10.99 μmol/L, P < 0.01; 11.96 μmol/L, P < 0.01, respectively). Cell counting kit-8 (CCK-8) assay, colony formation, and 5-ethynyl-2 '-deoxyuridine (EdU) assay showed that compared with the sensitive lines, the proliferative ability of the resistant lines decreased, but apoptosis staining showed a significant decrease in the level of cell apoptosis of the resistant lines (P < 0.01). Although resistant to axitinib, the resistant lines had no obvious new replicated cells in the environment of 20 μmol/L axitinib. Nuclear protein 1 (NUPR1) gene was screened by transcriptome sequencing, and its RNA (P < 0.0001) and protein expression levels significantly increased in the resistant lines. Database analysis showed that NUPR1 was significantly overexpressed in ccRCC tumor tissue (P < 0.05); the ccRCC patients with higher expression ofNUPR1had a worse survival prognosis (P < 0.001). Apoptosis staining results showed that knockdown ofNUPR1inhibited the anti-apoptotic ability of the resistant lines to axitinib (786-O, P < 0.01; Caki-1, P < 0.05). WB results showed that knocking downNUPR1decreased the protein level of B-cell lymphoma-2 (BCL2), increased the protein level of BCL2-associated X protein (BAX), decreased the protein level of pro-caspase3, and increased the level of cleaved-caspase3 in the resistant lines after being treated with axitinib.@*CONCLUSION@#ccRCC cell lines reduce apoptosis through theNUPR1 -BAX/ BCL2 -caspase3 pathway, which is involved in the process of resistance to axitinib.

MiR-744-5p inhibits the proliferation, invasion, and migration of clear-cell renal cell carcinoma cells by targeting CCND1 / 南方医科大学学报

OBJECTIVE@#To explore the role of miR-744-5p/CCND1 axis in clear-cell renal cell carcinoma (ccRCC).@*METHODS@#We examined the expression levels of miR-744-5p in 65 pairs of ccRCC and adjacent tissue specimens and in 5 ccRCC cell lines and human renal tubular epithelial (HK2) cells using qRT-PCR. The ccRCC cell lines 786-O and OSRC2 were transfected with miR-744-5p mimic, CCND1 mimic, or their negative control mimics, and the changes in cell proliferation, migration, and invasion were evaluated with CCK-8, wound healing, and Transwell assays. The downstream target molecules of miR-744-5p were predicted by bioinformatics analysis, and the expression level of CCND1 in ccRCC cells was verified by qRT-PCR and Western blotting. The relationship between miR-744-5p and CCND1 was further validated by dual luciferase reporter assay, and the role of the miR-744-5p/CCND1 axis in ccRCC was explored by rescue experiments.@*RESULTS@#MiR-744-5p was significantly downregulated in ccRCC tissues and cell lines (all P < 0.05), and its overexpression inhibited the proliferation, migration, and invasion of ccRCC cells (all P < 0.05). Bioinformatics analysis and dual luciferase reporter assay showed that CCND1 was a downstream target of miR-744-5p. The results of rescue experiments showed that upregulation of CCND1 could partially reverse the inhibitory effect of miR-744-5p overexpression on ccRCC cell proliferation, migration, and invasion (all P < 0.05).@*CONCLUSION@#MiR-744-5p inhibits the malignant phenotype of ccRCC cells by targeting CCND1, and the miR-744-5p/CCND1 axis may be a novel target for diagnosis and treatment of 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.

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.

Fosfatasa alcalina ósea sérica elevada no mediada por metástasis en un paciente con cáncer renal / Elevated bone alkaline phosphatase not mediated by metastasis in a patient with renal cancer

Presentamos un paciente de 63 años con cáncer renal y aumento de fosfatasa alcalina sérica de tipo óseo de acuerdo con su reactividad con anticuerpos monoclonales específicos. Se descartaron las causas conocidas de aumento de la isoenzima, incluyendo metástasis óseas. Los niveles enzimáticos cayeron abruptamente con la remoción del tumor, por lo que consideramos a este último como su origen. Diversas isoenzimas de fosfatasa alcalina pueden ser producidas y secretadas por tumores como manifestación paraneoplásica. El conocimiento de esto puede, en ocasiones, orientarnos hacia la presencia de una neoplasia oculta. Además, los cambios en los niveles séricos de esas isoenzimas pueden ser indicadores de respuesta al tratamiento o de recidiva tumoral. (AU)

A 63-year old man was seen in the outpatient clinic because of renal cancer and elevation in bone alkaline phosphatase measured by monoclonal antibodies assay. Known causes of bone isoenzyme augmentation, including bone metastases, were ruled out. The tumoral origin of the isoenzyme was diagnosed because after removal of the tumor the enzymatic levels fell sharply. Several alkaline phosphatase isoenzymes can be produced and secreted by tumors as a paraneoplasic manifestation and their elevation could be a manifestation of an occult neoplasia. Furthermore the monitoring of their blood levels can be useful means of treatment response and a tool to monitoring recurrence if a sharp decrease after removal of the tumor is observed. (AU)

A rare case of ectopic ACTH syndrome originating from malignant renal paraganglioma

SUMMARY Ectopic adrenocorticotropic hormone (ACTH) syndrome is characterized by hypercortisolism due to the hypersecretion of a non-pituitary ACTH-secreting tumor leading to Cushing's syndrome. Only a few cases have been reported previously as causing ectopic ACTH related to paraganglioma. Herein, we present a case of Cushing's syndrome, in who was proved to be attributable to an ACTH-secreting renal malignant paraganglioma. A 40-year-old woman presented with a five-month history of newly diagnosed hypertension and diabetes, weakness, hyperpigmentation, oligomenorrhea, hirsutism, and acneiform lesions. She showed cushingoid features, including moon face, facial hirsutism, facial and truncal acne, hyperpigmentation, and severe muscle weakness of the limbs. She did not have other findings such as striae, supraclavicular fat accumulation, and buffalo hump. Laboratory examination showed the presence of hypopotasemia, hyperglycemia, hyperthyroidism, and leukocytosis. The serum levels of ACTH, cortisol, and urine-free cortisol were markedly elevated. Results of an overnight 2-mg dexamethasone suppression test included a basal serum cortisol of 61.1 mcg/dL (normal range: 4.6-22.8 mcg/dL) and a cortisol value of 46.1 mcg/dL after dexamethasone administration. There was no suppression found after 2-day 8-mg dexamethasone administration. Magnetic resonance imaging (MRI) of the pituitary gland indicated two microadenomas. An abdominal MRI scan revealed horseshoe kidney, bilateral adrenal hyperplasia, and masses with dimensions of 35 x 31 mm in the left kidney. Inferior petrosal sinus sampling showed no evidence of a central-to-peripheral gradient of ACTH. A positron emission tomography/computed tomography scan showed intense increased activity in the lower pole of the left kidney. Left adrenalectomy and left partial nephrectomy were performed. The resected tumor was diagnosed as the ACTH-secreting paraganglioma in the pathological examination, which was confirmed by immunohistochemical studies with chromogranin A, synaptophysin, and ACTH. Only a few cases of paragangliomas as a cause of ectopic ACTH syndrome have been reported. To our knowledge, this is the first case of renal paraganglioma resulting in Cushing's syndrome due to ectopic ACTH hypersecretion.

Analysis of various potential prognostic markers and survival data in clear cell renal cell carcinoma

ABSTRACT Purpose Clear cell renal cell cancers frequently harbor Von Hippel-Lindau gene mutations, leading to stabilization of the hypoxia-inducible factors (HIFs) and their target genes. In this study, we investigated the relationship between vascular endothelial growth factor (VEGF), HIF-1α, HIF-2α, p53 positivity, microvessel density, and Ki-67 rates with prognostic histopathologic factors (Fuhrman nuclear grade, stage, and sarcomatoid differentiation) and survival in clear cell renal cell carcinomas. Material and Methods Seventy-two nephrectomy specimens diagnosed as clear cell renal cell carcinoma between 2000 and 2012 were reevaluated. Immunohistochemically VEGF, HIF-1α, HIF-2α, p53, CD34 (for microvessel density evaluation), and Ki-67 antibodies were applied to the tumor areas. The relationships of these antibodies with prognostic factors and survival rates were evaluated with statistical analyses. Results Mean survival time was 105.6 months in patients with ccRCC. Patients with high expression of VEGF, HIF-1α and HIF-2α positivity, a high Ki-67 proliferation index, and a high microvessel density evaluation score had a shorter survival time (p<0.05). Conclusions Our findings supported that with the use of these immunohistochemical markers, prognosis of renal cell carcinoma may be predicted at the first step of patient management. New treatment modalities targeted to HIF-1α and HIF-2α might be planned as well as VEGF-targeted therapies in the management of clear cell renal cell carcinomas.

Orai1 Expression Is Closely Related with Favorable Prognostic Factors in Clear Cell Renal Cell Carcinoma

Store-operated calcium (Ca2+) entry (SOCE) is the principal Ca2+ entry route in non-excitable cells, including cancer cells. We previously demonstrated that Orai1 and STIM1, the molecular components of SOCE, are involved in tumorigenesis of clear cell renal cell carcinoma (CCRCC). However, a clinical relevance of Orai1 and STIM1 expression in CCRCC has been ill-defined. Here, we investigated the expression of Orai1 and STIM1 in CCRCC, and compared their expression with clinico-pathological parameters of CCRCC and the patients' outcome. Immunohistochemical staining for Orai1 and STIM1 was performed on 126 formalin fixed paraffin embedded tissue of CCRCC and western blot analysis for Orai1 was performed on the available fresh tissue. The results were compared with generally well-established clinicopathologic prognostic factors in CCRCC and patient survival. Membrane protein Orai1 is expressed in the nuclei in CCRCC, whereas STIM1 shows the cytosolic expression pattern in immunohistochemical staining. Orai1 expression level is inversely correlated with CCRCC tumor grade, whereas STIM1 expression level is not associated with tumor grade. The higher Orai1 expression is significantly associated with lower Fuhrman nuclear grade, pathologic T stage, and TNM stage and with favorable prognosis. The expression level of STIM1 is not correlated with CCRCC grade and clinical outcomes. Orai1 expression in CCRCC is associated with tumor progression and with favorable prognostic factors. These results suggest that Orai1 is an attractive prognostic marker and therapeutic target for CCRCC.

Increased Tissue Factor Expression is an Independent Predictor of Mortality in Clear Cell Carcinoma of the Kidney

Purpose Increased expression of tissue factor (TF), a primary initiator of the extrinsic coagulation pathway, has been associated with a worse prognosis in a variety of solid tumors. We report for the first time the correlation of the immunohistochemical expression of tissue factor with clinical and pathological outcomes in clear cell carcinomas of the kidney. Materials and Methods immunohistochemical expression of tissue factor was evaluated in 58 paraffin-embedded samples of clear cell carcinomas of the kidney treated at the same university hospital, that was correlated with clinical and pathological variables and with overall survival. Results high intensity tissue factor expression (TF area > 10µm2) was observed in 22.4% of the tumors (13 patients), and was an important predictor of overall mortality, both in univariate and multivariate analysis (p < 0.05). Median overall survival for both groups was 66 months; 78.2 months for patients in the group of lower TF expression and 27.5 months for patients in the group of higher TF expression (log rank p < 0.001). The hazard ratio for mortality was 9.7 (CI 3.7-25.6) for tumors with increased TF expression. Conclusions Increased immunohistochemical expression of TF was an important independent predictor of mortality in a contemporary cohort of patients with clear cell carcinoma of the kidney. Further studies are necessary to define the role of TF in clinical practice. .

Expression of VEGF-A, HIF-1 A, CD34 and Ki67 in clear cell renal cell carcinomas and their relationship with conventional prognostic markers / Expression of VEGF-A, HIF-1 A, CD34 and Ki67 in clear cell renal cell carcinomas and their relationship with conventional prognostic markers.

Clear cell renal carcinoma is the most frequent type of renal carcinoma. Recently, attention has been focused in the expression of angiogenic factors by these tumors, which would justify in part their capacity to grow, invade and disseminate, stating a worse evolution of those patients with an unfavorable angiogenic profile. 83 samples of nephrectomy with a diagnosis of clear cell renal cell carcinoma were studied. Clinical and pathological data were collected. Tumors were studied to assess immunohistochemical expression of the following markers: VEGF-A, HIF-1α, CD34 and Ki67. Results indicated a direct linear relationship between expressions of these four markers. Besides, the expression of HIF-1α was directly related to Furhman grade, invasion of the renal vein and tumor stage. Likewise, tumor proliferation index, assessed with Ki67, was directly related to the presence of necrosis, capsular invasion and advanced tumor stage. Regarding the expression of CD34, vascular density was inversely related to tumor necrosis and overall survival. These findings are controversial compared with the available literature. Then, a research scenery would be open, where the importance of generating prospective and more standardized studies are highlighted to determine the role of these angiogenic factors in tumor evolution and prognostic evaluation of these tumors.

Anti-carcinogenic potential of Euphorbia neriifolia leaves and isolated flavonoid against N-Nitrosodiethylamine-induced renal carcinogenesis in mice.

Anti-carcinogenic potential of hydro-ethanolic extract of Euphorbia neriifolia (EN) leaves and an isolated flavonoid (ENF) was investigated against N-Nitrosodiethylamine (DENA)-induced renal carcinogenesis in mice. Experimental mice were pretreated with 150 and 400 mg/kg body wt of EN, 0.5% and 1% mg/kg body wt of butylated hydroxylanisole (BHA) as a standard antioxidant and 50 mg/kg body wt of ENF for 21 days prior to the administration of a single dose of 50 mg/kg body wt of DENA. Levels of renal markers (urea and creatinine), xenobiotic metabolic enzymes (Cyt P450 and Cyt b5), lipid peroxidation (LPO), antioxidants (SOD, CAT, GST and GSH) and other biochemical parameters — AST, ALT, ALP, total protein (TP), and total cholesterol (TC) were measured to determine the renal carcinogenesis caused by DENA. DENA administration significantly (p<0.001) decreased the body weight and increased the tissue weight. It significantly (p<0.001) enhanced the levels of Cyt P450, Cyt b5 and LPO and decreased the levels of SOD, CAT, GST and GSH content. The activities of AST, ALT and ALP and the TP content and renal markers were also significantly decreased (p<0.001), while TC level was markedly increased after DENA administration, as compared with the normal control group (p<0.001). Pretreatment with EN and ENF counteracted DENA-induced oxidative stress (LPO) and exerted its protective effects by restoring the levels of antioxidants (SOD, CAT, GST and GSH), biochemical parameters (AST, ALT, ALP, TP and TC), renal markers (urea and creatinine) and xenobiotic enzymes (Cyt P450 and Cyt b5) in renal tissue. In conclusion, the present study showed significant anti-carcinogenic potential of the hydro-ethanolic extract of E. neriifolia and ENF against DENA-induced renal carcinogenicity.

Esfingosina-1-fosfato y cánceres urológicos: identificando potenciales blancos terapéuticos en su etabolismo y señalización / Sphingosine-1-phosphate and urological cancers: identifying potential therapeutic targets in its metabolism and signalling

Los lípidos no sólo son moléculas estructurales de las membranas. Hay numerosos ejemplos de lípidos que median acciones fisiológicas dentro de las células. Específicamente, esfingolípidos como ceramida, esfingosina y esfingosina-1-fosfato (S1P) han sido involucrados en el control del crecimiento celular, la proliferación y la migración, todo lo cual se ha relacionado con el cáncer.Los efectos pro-apoptóticos de la ceramida y la esfingosina son revertidos por S1P. Por lo tanto, el destino de la célula puede ser modulada mediante el cambio de la proporción de estos esfingolípidos (el modelo reóstato). S1P promueve la proliferación celular, el crecimiento, la supervivencia, la migración, invasión y resistencia fármacos y radiación, en parte a través de receptores de membrana (S1PR1-5). La sobreexpresión de enzimas productoras de S1P y el aumento de los niveles de S1P se ha descrito en muchos tipos de cáncer, incluyendo cánceres urológicos. Por lo tanto, se pueden identificar posibles objetivos terapéuticos en el metabolismo y las vías de señalización de los esfingolípidos, cuya relevancia clínica debe ser determinada en futuros estudios.

Lipids are not only structural molecules of the membranes. There are numerous examples of lipids mediating physiologic actions within the cells. Specifically, sphingolipids like ceramide, sphingosine and sphingosine-1-phosphate (S1P) have been described to be involved in the control of cell growth, proliferation and migration, all of which has been linked to cancer. The pro-apoptotic effects of ceramide and sphingosine are opposed by S1P. Therefore, the fate of the cell can be modulated by changing the ratio of these sphingolipids (the rheostat model). S1P promotes cell proliferation, growth, survival, migration, invasion and resistance to drugs and radiation, in part mediated by S1P membrane receptors (S1PR1-5). Overexpression of S1P producing enzymes and increased S1P levels has been described in many cancers, including urological cancers. Therefore, potential therapeutic targets can be recognized in the metabolism and signaling pathways of sphingolipids and their clinical relevance have to be determined in future studies.

Serum protein profiling to identify biomarkers for small renal cell carcinoma.

Diagnostic biomarkers for early detection of renal cell carcinoma (RCC) are in great need. In the present study, we compared the serum protein profiles of patients with small RCC to those of healthy individuals to identify the differentially expressed proteins with potential to serve as biomarkers. Serum samples were collected from 10 patients with small RCC and 10 healthy individuals. The serum protein expression profiles were analyzed by two-dimensional (2-D) gel electrophoresis. Twenty-seven proteins with differences in expression levels between RCC patients and healthy volunteers were identified. Of these, 19 were expressed at different levels and eight were expressed in serum from the RCC group, but not from the control group. Six differentially expressed proteins identified by using mass spectrometry included coagulation factor XIII B, complement C3 and its precursor, misato homolog 1 (isoform CRA_b), hemopexin, and alpha-1-B-glycoprotein. Some of these serum proteins are known regulators of tumor progression in human malignancies. In conclusion, we successfully applied 2-D gel electrophoresis and identified six serum proteins differentially expressed between patients with small RCC and healthy volunteers. These proteins may provide novel biomarkers for early detection and diagnosis of human RCC.

MET Expression in Sporadic Renal Cell Carcinomas

Although germline mutations of met proto-oncogene on human chromosome 7q31-34 have been known as useful molecular markers of hereditary papillary renal cell carcinoma (RCC), the expression of MET, a product of met proto-oncogene, has not been fully studied in sporadic RCC, along with its clinical significance. We investigated the expression of MET by immunohistochemistry in 182 cases of renal neoplasm encompassing 145 RCC, 25 urothelial carcinomas of renal pelvis, and 12 oncocytomas. MET was diffusely and strongly expressed in 90% of papillary RCC, all collecting duct carcinomas, and 92% of urothelial carcinomas of renal pelvis. On the contrary, clear cell RCC, chromophobe RCC, and oncocytomas were negative or focally positive for MET expression. In clear cell RCC, MET expression was positively correlated with high nuclear grade, presence of infiltrative growth, tumoral necrosis, papillary architecture, sarcomatoid component, tumoral involvement of the renal pelvis or ureter, involvement of the calyx, and lymphatic invasion. In conclusion, diffuse and strong expression of MET in papillary RCC and collecting duct carcinoma might be helpful in discriminating from the other subtypes of RCC with tubular or papillary growth. In case of MET expression observed in clear cell RCC, it might correlate with those clinicopathological parameters implying aggressive behavior.

Identification of Proteins Differentially Expressed in the Conventional Renal Cell Carcinoma by Proteomic Analysis

Renal cell carcinoma (RCC) is one of the most malignant tumors in urology, and due to its insidious onset patients frequently have advanced disease at the time of clinical presentation. Thus, early detection is crucial in management of RCC. To identify tumor specific proteins of RCC, we employed proteomic analysis. We prepared proteins from conventional RCC and the corresponding normal kidney tissues from seven patients with conventional RCC. The expression of proteins was determined by silver stain after two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). The overall protein expression patterns in the RCC and the normal kidney tissues were quite similar except some areas. Of 66 differentially expressed protein spots (p<0.05 by Student t-test), 8 different proteins from 11 spots were identified by MALDI-TOF-MS. The expression of the following proteins was repressed (p<0.05); aminoacylase-1, enoyl-CoA hydratase, aldehyde reductase, tropomyosin alpha-4 chain, agmatinase and ketohexokinase. Two proteins, vimentin and alpha-1 antitrypsin precursor, were dominantly expressed in RCC (p<0.05).

Cyclooxygenase-2 and p53 Expression as Prognostic Indicators in Conventional Renal Cell Carcinoma

The aim of this study was to investigate the relationship of cyclooxygenase (COX) -2 and p53 expression with prognosis in patients with conventional renal cell carcinoma (RCC). Formalin-fixed, paraffin-embedded tissue sections of conventional RCC from 92 patients, who had undergone radical nephrectomy, were examined for COX-2 and p53 expression by immunohistochemistry and compared with clinicopathological variables. The COX-2 expression significantly correlated only with tumor size (p=0.049), whereas the p53 expression profoundly correlated with the TNM stage (p=0.024), M stage (p=0.001), and metastasis (synchronous or metachronous; p= 0.004). The COX-2 overexpression did not significantly associate with p53 positivity (p=0.821). The survival rate of patients correlated with the p53 expression (p < 0.0001) but not with the COX-2 expression (p=0.7506). Multivariate analyses indicated that tumor size, M stage, and p53 expression were independent prognostic factors for cancer-specific survival. The COX-2 expression was not an independent factor. These results show that the increased expression of p53 was associated with metastasis and a worse prognosis in conventional RCC, which suggests that p53 might have played an important role in the progression of conventional RCC. The increased expression of COX-2 was associated only with tumor size, but may not be an important prognostic factor in conventional RCC. No association was observed between COX-2 overexpression and p53 positivity in conventional RCC.

Sarcomatoid renal cell carcinoma with osteosarcomatous differentiation--a case report.

A rare case of sarcomatoid renal cell carcinoma (RCC) with predominantly osteosarcomatous differentiation occurring in a 36-year-old male is reported. Immunohistochemistry excluded the possibility of primary osteosarcoma of the kidney.

Pan-cytokeratin immunoexpression in Wilms' tumors: a simple approach for understanding tumor epithelial differentiation

Os tumores de Wilms são alguns dos mais freqüentes tumores sólidos da infância e reconhecidamente um modelo para a compreensão da patogênese dos tumores embrionários. As citoqueratinas são proteínas intracelulares presentes em tecidos de origem epitelial. Estudamos a imunoexpressão da pan-citoqueratina AE1AE3 em 24 tumores de Wilms, dentre ao quais 15 continham também tecidos renais não-neoplásicos e 12 apresentavam restos nefrogênicos em blocos de parafina, para avaliar a diferenciação epitelial no desenvolvimento dos tumores de Wilms. Observamos aumento na intensidade de expressão de AE1AE3 no componente epitelial dos tumores de Wilms diretamente relacionado ao grau de maturação das estruturas epiteliais correspondentes aos ductos coletores.