Morphometric index of adult renal cell carcinoma. Comparison with the Fuhrman grading system

Expression of CREPT is associated with poor prognosis of patients with renal cell carcinoma

Cell-cycle-associated and expression-elevated protein in tumor (CREPT) functions as a cell cycle modulator that enhances the transcription of cyclin D1 by interacting with RNA polymerase II. CREPT has been identified to be overexpressed in various human cancer types; however, the expression and significance of CREPT in renal cell carcinoma (RCC) has remained largely elusive. In the present study, increased expression of CREPT was identified in 46.7% RCC tissues compared with adjacent normal tissue (31.1%; P=0.032) using immunohistochemistry. Furthermore, overexpression of CREPT was significantly associated with the Tumor-Node-Metastasis stage (χ²=11.967, P=0.001) and Fuhrman grade (χ²=15.453, P<0.001). In addition, increased expression of CREPT was associated with poor overall survival (P=0.021) and disease-free survival (P=0.015) of patients according to Kaplan-Meier analysis. Cellular function assays demonstrated that knockdown of CREPT in the 786-O and 769P RCC cell lines suppressed their proliferative, colony formation, migratory and invasive capacity and led to cell cycle arrest in the G1 phase. In addition, the western blotting analysis demonstrated that CREPT may control the cell cycle through downregulation of cyclin D1 and c-myc. Collectively, the overexpression of CREPT was indicated to be a negative prognostic factor for RCC, and CREPT may serve as a novel therapeutic target for the treatment of RCC.

Expression of micro-RNAs and genes related to angiogenesis in ccRCC and associations with tumor characteristics

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the third most common urological cancer in adults. Our aim is to evaluate genes and miRNAs expression profiles involved with angiogenesis and tumor characteristics in ccRCC.

METHODS

The expression levels of miRNAs miR-99a, 99b, 100; 199a; 106a; 106b; 29a; 29b; 29c; 126; 200a, 200b and their respective target genes: mTOR, HIF1-α, VHL, PDGF, VEGF, VEGFR1 and VEGFR2 were analyzed using qRT-PCR in tumor tissue samples from 56 patients with ccRCC. Five samples of benign renal tissue were utilized as control. The expression levels of miRNAs and genes were related to tumor size, Fuhrman nuclear grade and microvascular invasion.

RESULTS

miR99a was overexpressed in most samples and its target gene mTOR was underexpressed, this also occurs for miRNAs 106a, 106b, and their target gene VHL. An increase in miR-200b was correlated with high-risk tumors (p = 0.01) while miR-126 overexpression was associated with Fuhrman's low grade (p = 0.03).

CONCLUSIONS

Our results show that in ccRCC there are changes in miRNAs expression affecting gene expression that could be important in determining the aggressiveness of this lethal neoplasia.

Prognostic value of pathological features of primary lesion in metastatic renal cell carcinoma treated with sorafenib

AIM

This study aimed to investigate whether the pathological features of primary lesions show additional prognostic value in patients with metastatic renal cell carcinoma who are treated with sorafenib.

PATIENTS & METHODS

A consecutive cohort of 284 patients was included from Fudan University Shanghai Cancer Center between 2007 and 2013. The association between survival and pathological features of primary tumors was assessed using the Cox proportional hazards model. The incremental value of prognostication was evaluated.

RESULTS

We found that the pathological features of primary lesions provided added prognostic value over the Memorial Sloan-Kettering Cancer Center model in patients with metastatic renal cell carcinoma who were treated with sorafenib.

CONCLUSION

Addition of a pathological score in the clinical setting could better identify patients at risk of poor survival.

Effects of the novel heat shock protein 90 inhibitor AUY922 in renal cell carcinoma ACHN and 786-O cells

The aim of the present study was to investigate the effects of the heat shock protein (HSP)90 inhibitor AUY922 on the proliferation and migratory ability of renal cell carcinoma (RCC) cells. The expression of HSP90 was measured in vitro using western blotting and quantitative polymerase chain reaction in the ACHN and 786-O cell RCC lines, and also in the immortalized normal human proximal tubule epithelium HK-2 cell line. The effects of the time and concentration of AUY922 administration were investigated in the ACHN and 786-O cells, and the cell proliferation was measured using an MTT assay. A Transwell assay was performed to evaluate the migratory ability of ACHN cells following treatment with AUY922 at concentrations of 10, 50 and 100 nM. Western blot analysis and reverse transcription polymerase chain reaction revealed that HSP90 mRNA and protein were overexpressed in the two RCC cell lines compared with the HK-2 cell line. AUY922 inhibited the proliferation of the ACHN and 786-O cells in a time- and concentration-dependent manner, and the migratory ability of the ACHN cells was markedly suppressed subsequent to treatment with AUY922. The present data suggest that the pathogenesis of human RCC may be mediated by HSP90. It was also indicated that the specific HSP90 inhibitor AUY922 plays a therapeutic role in the treatment of RCC, and therefore, HSP90 may be a selective target for molecular-targeted treatments of RCC.

Increased expression of Chitinase 3-like 1 and microvessel density predicts metastasis and poor prognosis in clear cell renal cell carcinoma

Increasing evidence demonstrated that Chitinase 3-like 1 (hereafter termed CHI3L1 or YKL-40) was highly expressed and tightly associated with human tumor development and progression. However, its precise role in clear cell renal cell carcinoma (hereafter termed RCC) remains to be delineated. In the present study, we investigated the relationship between CHI3L1 expression and microvessel density (MVD), a reflection of angiogenesis, with metastasis and prognosis in patients with clear cell renal cell carcinoma (RCC). Formalin-fixed, paraffin-embedded tissue sections of clear cell RCC from 73 patients who had undergone radical nephrectomy were stained immunohistochemically with specific antibodies against CHI3L1 and CD34. CHI3L1 immunostaining was semi-quantitatively estimated based on the proportion (percentage of positive cells) and intensity. MVD was determined with CD34-stained slides. The expression pattern of CHI3L1 and MVD was compared with the clinicopathological variables. Twenty patients had either synchronous or metachronous metastases and 12 died during the follow-up. CHI3L1 intensity was significantly correlated with tumor size (P = 0.005), TNM stage (P = 0.027), M stage (P = 0.011), grade (P = 0.014), and metastasis (synchronous or metachronous; P < 0.001). The CHI3L1 proportion (P = 0.038) and MVD (P = 0.012) were significantly correlated with metastasis. MVD was correlated with CHI3L1 intensity (r = 0.376, P = 0.001) and CHI3L1 proportion (r = 0.364, P = 0.002). There was no difference in the expression of CHI3L1 and MVD between primary and metastatic sites. The survival of patients with higher CHI3L1 intensity was significantly worse than that of patients with lower CHI3L1 intensity. Multivariate analyses indicated that only M stage was an independent prognostic factor for cancer-specific survival and CHI3L1 expression was not an independent factor. Taken altogether, increased expression of CHI3L1 and MVD is associated with metastasis and a worse prognosis in clear cell RCC. CHI3L1 expression is correlated with MVD. The results suggest that CHI3L1 may be important in the progression and angiogenesis of clear cell RCC and CHI3L1 might be a novel strategy for therapy of the patients with RCC.

GATA-3 is down-regulated in patients with clear cell renal carcinoma

BACKGROUND

GATA-3 is a transcription factor involved in human growth and development. Recent studies found its association with breast cancer, however, its expression profile in renal cell carcinoma (RCC) has not been investigated.

MATERIAL AND METHOD

The study included 35 patients submitted to radical nephrectomy with confirmed pathological diagnosis of RCC. Normal control kidney tissues were obtained from 25 living kidney donors and tissues were biopsied before implantation. The majority of RCC samples were diagnosed as clear cell renal cell carcinoma (94.3%) except for 1 case of papillary RCC and 1 case of collecting duct carcinoma. GATA-3 expression was evaluated by quantitative PCR and Western blotting (WB) in RCC samples and normal kidneys respectively, immunohistochemical staining was performed as well. Meanwhile, the GATA-3 expression in two cancer cell lines (786-O, ACHN) and normal kidney epithelial cells (HK-2) was detected by PCR and WB. In addition, renal cancer cells and HK-2 cells were cultivated and detected by confocal microscopy for the exact intra-cellular localization of GATA-3.

RESULTS

Data showed a significant down-regulation of GATA-3 expression present in neoplastic tissues compared with normal tissues; similarly, GATA-3 was significantly attenuated in all renal cancer cell lines compared with normal HK-2 cells. Confocal displayed a strong cytoplasmic immno-fluorescence activity of GATA-3 with peri-nuclear zone in HK-2, whereas the intensity in cancer cells was markedly weaker than that of HK-2.

CONCLUSIONS

In summary, our present study clarifies that the aberrant expression profile of GATA-3 in human RCC is possibly involved with tumorigenesis, and the complicated mechanism is worthy of further investigation.

Grading Systems in Renal Cell Carcinoma

PURPOSE

We reviewed updated literature data concerning several issues of renal cell carcinoma grading systems.

MATERIALS AND METHODS

We performed a nonsystematic review of the literature. Data were identified by a MEDLINE search using a strategy including MeSH and free text protocols. From the MEDLINE search we collected 184 records.

RESULTS

Although the original study was published in 1982, the independent predictive value of nuclear grades was only revealed in 2000 by the team from University of California-Los Angeles. Subsequently further data from our group and the group at the Mayo Clinic reconfirmed those findings, although similar cancer specific survival probabilities were noted among different grades. The prognostic relevance of nuclear grade justified the inclusion of that variable in algorithms and nomograms predictive of cancer specific survival, such as those provided by University of California-Los Angeles, the Mayo Clinic and Memorial Sloan-Kettering Cancer Center. Despite the routine clinical use of nuclear grade, several drawbacks have affected grading systems, such as interobserver and intra-observer reproducibility, and variability of the cancer specific survival probabilities stratified by grade. Several studies showed that intra-observer and interobserver agreement with regard to grade are only moderate with up shifting in all series. That issue might be due to the heterogeneity of renal cell carcinoma as well as to the lack of consensus about the minimal size of high grade tumor to be considered significant. Moreover, recent data underscore the role of histological subtypes.

CONCLUSIONS

Grade is one of the most powerful prognostic factors in patients with renal cell carcinoma. The Fuhrman grading system is currently most widely used by pathologists in Europe and the United States. However, there is still a need for better standardization of nuclear criteria to improve interobserver reproducibility and a major consensus should be achieved by uropathologists.

Expression of gastrin releasing Peptide receptor in renal cell carcinomas: a potential function for the regulation of neoangiogenesis and microvascular perfusion

PURPOSE

Gastrin releasing peptide (GRP) is a growth factor for renal cell carcinoma (RCC) and it has vasoactive properties. Blockade of GRP receptor inhibits the growth of GRP receptor positive and negative tumors in nude mice, suggesting GRP effects other than those related to tumor epithelium. Therefore, in this study we analyzed the effects of GRP receptor blockade on neoangiogenesis in RCC.

MATERIALS AND METHODS

GRP receptor expression was determined in human RCC and corresponding normal tissue by real-time reverse transcriptase-polymerase chain reaction, immunohistochemistry and confocal laser scanning microscopy. Multicellular spheroids of the A498 RCC line were implanted into dorsal skin fold chambers of athymic nude mice. Neoangiogenesis was measured by intravital microscopy after blockade of GRP receptors by the GRP antagonist RC-3095. The influence of GRP on vascular endothelial growth factor secretion in A498 cells was studied in vitro.

RESULTS

GRP receptor expression was immunolocalized in tumor cells and microvessels. Implanted tumor cell spheroids and spheroid microvessels of the chamber also expressed GRP receptors. Spheroid neoangiogenesis was significantly inhibited by RC-3095 when given immediately after spheroid implantation. Vascular endothelial growth factor secretion of A498 cells was not affected by GRP.

CONCLUSIONS

RCC angiogenesis is sensitive to GRP receptor blockade. Therefore, GRP receptors may not only stimulate tumor cell proliferation, but also affect tumor microcirculation.