The prognostic relevance of interactions between venous invasion, lymph node involvement and distant metastases in renal cell carcinoma after radical nephrectomy

Development and internal validation of nomograms for the prediction of postoperative survival of patients with grade 4 renal cell carcinoma (RCC)

Background

To develop successful prognostic models for grade 4 renal cell carcinoma (RCC) following partial nephrectomy and radical nephrectomy.

Methods

The nomograms were established based on a retrospective study of 135 patients who underwent partial and radical nephrectomy for grade 4 RCC at the Department of Urology, Peking University First Hospital from January 2013 to October 2018. The predictive performance of the nomograms was assessed by the calibration plot and C-index. The results were validated using bootstrap resampling.

Results

Aspartate transaminase (AST), the maximum diameter of tumor (cutoff value =7 cm), lymph node metastasis, and the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk group were independent factors for determining the overall survival (OS) and cancer-specific survival (CSS) in multivariate analysis. AST, the maximum diameter of the tumor (cutoff value =7 cm), and lymph node metastasis were found to be independent variables for progression-free survival (PFS) in multivariate analysis. These variables were used for the studies to establish nomograms. All calibration plots revealed excellent predictive accuracy of the models. The C-indexes of the nomograms for predicting OS, CSS and PFS were 0.729 (95% CI, 0.659-0.799), 0.725 (95% CI, 0.654-0.796) and 0.702 (95% CI, 0.626-0.778), respectively. Moreover, the recurrence rate was not associated with open or laparoscopic radical nephrectomy in our cohort (P=0.126).

Conclusions

We have developed easy-to-use models that are internally validated to predict postoperative 1-, 3-, and 5-year OS, CSS, and PFS rates of grade 4 RCC patients. The new models could aid in identifying high-risk patients, making postoperative therapeutic and follow-up strategies as well as predicting patients' survival after externally validated. Besides, our study shows that the recurrence rate is not associated with open or laparoscopic radical nephrectomy.

Human telomerase reverse transcriptase protein expression predicts tumour aggressiveness and survival in patients with clear cell renal cell carcinoma

Human telomerase reverse transcriptase (hTERT) is an active component of telomerase and responsible for its catalytic activity, associated with cell proliferation and differentiation. For the first time, the present study was conducted to evaluate the expression and prognostic significance of hTERT in different histological subtypes of renal cell carcinoma (RCC). Expression of hTERT was examined in 176 well-defined renal tumour samples including clear cell RCCs (ccRCCs), papillary and chromophobe RCCs using immunohistochemistry on tissue microarrays. The association between hTERT expression and clinicopathological parameters as well as survival outcomes were then analysed. There was a statistically significant difference in terms of hTERT expression among various RCC subtypes. In ccRCC, increased expression of hTERT was significantly associated with advanced stage, higher grade, presence of microvascular invasion, lymph node invasion, and metastasis. Moreover, in the multivariate analysis, tumour stage and tumour size were independent predictors of the disease-specific survival (DSS). Additionally, expression of hTERT was found to be a significant predictor of worse DSS (p = 0.012) in the univariate analysis. In papillary carcinoma samples (type I and II), significant association was detected between hTERT expression and the tumour stage (p = 0.010, p = 0.050), respectively. In chromophobe RCC, no significant association was detected between expression of hTERT and clinicopathological parameters and survival data. We showed that hTERT protein expression was associated with more aggressive tumour behaviour and more advanced disease in ccRCC patients. Also, hTERT may be a novel poor prognostic indicator of DSS, if the patients are followed for more prolonged time periods.

Increased expression of CD44 is associated with more aggressive behavior in clear cell renal cell carcinoma

AIM

Although CD44 has been suggested as a prognostic marker in renal cell carcinoma (RCC), the prognostic significance of this marker in three main subtypes of RCC is still unclear. Thus, the present study was conducted to evaluate the expression and prognostic significance of CD44 as a cancer stem cell marker in different histological subtypes of RCC. Methodology & results: CD44 expression was evaluated in 206 well-defined renal tumor samples using immunohistochemistry on tissue microarrays. Higher CD44 expression was associated with more aggressive behavior, tumor progression and worse prognosis in clear cell RCC (ccRCC) but not in papillary and chromophobe RCC subtypes.

DISCUSSION & CONCLUSION

Cancer stem cell marker CD44 may be a promising target for cancer treatment only in ccRCC.

Cytoplasmic expression of CD133 stemness marker is associated with tumor aggressiveness in clear cell renal cell carcinoma

Prominin-1 (CD133) is one of the most commonly used markers for cancer stem cells (CSCs), which are characterized by their ability for self-renewal and tumorigenicity. However, the clinical and prognostic significance of CSCs in renal cell carcinoma (RCC) remains unclear. The aim of this study was to investigate the expression patterns and prognostic significance of the cancer stem cell marker CD133 in different histological subtypes of RCC. CD133 expression was evaluated using immunohistochemistry in 193 well-defined renal tumor samples on tissue microarrays, including 136 (70.5%) clear cell renal cell carcinomas (CCRCCs), 26 (13.5%) papillary RCCs, and 31 (16.1%) chromophobe RCCs. The association between CD133 expression and clinicopathological features as well as the survival outcomes was determined. There was a statistically significant difference between CD133 expression among the different RCC subtypes. In CCRCC, higher cytoplasmic expression of CD133 was significantly associated with increase in grade, stage, microvascular invasion (MVI) and lymph node invasion (LNI), while no association was found with the membranous expression. Moreover, on multivariate analysis, TNM stage and nuclear grade were independent prognostic factors for overall survival (OS) in cytoplasmic expression. We showed that higher cytoplasmic CD133 expression was associated with more aggressive tumor behavior and more advanced disease in CCRCC but not in the other examined subtypes. Our results demonstrated that higher cytoplasmic CD133 expression is clinically significant in CCRCC and is associated with increased tumor aggressiveness and is useful for predicting cancer progression.

Recurrence pattern in patients with locally advanced renal cell carcinoma: The implications of clinicopathological variables

Objectives

Recurrence rates for patients with locally advanced renal cell carcinoma (LARCC) remain high. To date the predictors of recurrence in those patients remain controversial. The aim of the present study was to assess the relapse pattern in those patients and identify predictors for recurrence.

Patients and methods

We evaluated retrospectively 112 consecutive patients who underwent surgery for LARCC (T3–T4N0M0) between January 2000 and December 2010. Clinical and pathological data were collected from hospital medical records and compiled into a computerized database. Studied variables were age, mode of presentation, Tumour-Node-Metastasis (TNM) stage, Fuhrman nuclear grade, histological subtype, tumour size, venous thrombus level, collecting-system invasion and sarcomatoid differentiation. Recurrence-free survival (RFS) was estimated using the Kaplan–Meier method. Univariate and multivariate analyses were conducted.

Results

Patients were followed for a mean and median follow-up of 33 and 24 months, respectively, after surgery. During the follow-up, recurrences (distant and/or local) were recorded in 58 patients, representing 52% of the cohort. The mean and median times to recurrence were 25 and 13 months, respectively. Sites of recurrence were multiple in 36 patients (62%), lung only in 14 (24%), and local in eight (14%). RFS rates at 1, 2, and 5 years were 50%, 43% and 34%, respectively, while the median RFS was 23.7 months. Using univariate analysis, RFS after nephrectomy was significantly shorter in patients aged <70 years, symptomatic at presentation, with larger tumours, higher nuclear grade, collecting-system invasion, and/or sarcomatoid differentiation. After multivariate analysis, T-stage, nuclear grade and sarcomatoid differentiation retained their power as independent predictors of RFS (P = 0.032, <0.001 and 0.003, respectively).

Conclusions

For patients with LARCC, T-stage, grade and sarcomatoid differentiation independently dictate the risk of tumour recurrence. Considering these variables in the postoperative surveillance protocols and in the need for a multimodal therapeutic approach is highly recommended.

Clinical, molecular, and genetic correlates of lymphatic spread in clear cell renal cell carcinoma

BACKGROUND

While it is well known that clear cell renal cell carcinoma (ccRCC) that presents with lymphatic spread is associated with an extremely poor prognosis, its molecular and genetic biology is poorly understood.

OBJECTIVE

Define the clinicopathologic, molecular, and genetic biological characteristics of these tumors in comparison to nonmetastatic (N0M0) renal cell carcinomas.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective study defined clinicopathologic features, expression of 28 molecular markers, and occurrence of chromosomal aberrations for their correlation with lymphatic spread in three cohorts of 502, 196, and 272 patients, respectively.

MEASUREMENTS

Fisher exact test or the χ(2) test were used to compare categorical variables; continuous variables were compared with the Mann-Whitney U test or student t test. Cut-off values were calculated based on receiver operating characteristic curves and the Youden Index. Uni- and multivariate regression analyses were used to investigate the correlation with lymphatic spread.

RESULTS AND LIMITATIONS

In clinical analyses, a predictive model consisting of smoking history (p=0.040), T stage (p<0.0001), Fuhrman grade (p<0.0001), Eastern Cooperative Oncology Group performance status (p<0.0001), and microvascular invasion (p<0.0001) was independently associated with lymphatic spread. After adjustment with these clinical variables, low carbonic anhydrase IX (CAIX) (p=0.043) and high epithelial vascular endothelial growth factor receptor 2 (p=0.033) protein expression were associated with a higher risk of lymphatic spread, and loss of chromosome 3p (p<0.0001) with a lower risk. The current study is limited by its retrospective design, small sample size, and single-center experience.

CONCLUSIONS

The low rates of CAIX expression and loss of chromosome 3p suggest that lymphatic spread in ccRCC occurs independently of von Hippel-Lindau tumor suppressor inactivation.

Differential response of human and mouse dendritic cells to VEGF determines interspecies discrepancies in tumor-mediated TH1/TH2 polarity shift

PURPOSE

Metastatic cancer patients exhibit systemic dysregulation of immune polarity and are biased toward Th-2 immune responses. This is due, at least in part, to effects of VEGF on antigen presenting cell (APC) function. We therefore compared immune polarity changes in mouse models of cancer with those seen in human patients.

EXPERIMENTAL DESIGN

We measured plasma levels of vascular growth factors and multiple cytokines via ELISA and multiplex analysis in mice with transplantable and spontaneous tumors. We compared immune cell subsets in naive and vaccinated mice with and without tumors. We assessed cytokine immune responses by multiplex analysis. Finally, we assessed gene expression and receptor surface expression in response to VEGF in mouse and human APCs.

RESULTS

Although human patients have elevated plasma cytokines and altered immune polarity in response to antigen, mice have minimal immune abnormalities. Mouse VEGF does not mediate immune repolarization in vitro. Human but not mouse APCs upregulate VEGFR2 and downregulate interleukin (IL)-12β in response to VEGF.

CONCLUSIONS

Whereas humans with metastatic cancer demonstrate dysregulated immune polarity in response to excess plasma VEGF, tumor mice do not. This appears to be due to differences in APC responses to VEGF stimulation. Differential immune effects of VEGF may represent a key species difference in the context of translation of preclinical cancer immunotherapeutics into early clinical testing.

Significance of nm23 Immunoexpression in the Prognosis of Renal Cell Carcinoma

Non-metastatic gene 23 (nm23) is a metastasis suppressor gene that is expressed in all tissues and decreased nm23 expression may be linked to poor prognosis. By immunohistochemical staining of nm23 protein antibodies this study examined the prognostic value of nm23 protein expression in 54 renal cell carcinoma (RCC) patients and analysed its relationship with tumour, node, metastases (TNM) surgical stage, Fuhrman nuclear grade, lymph node involvement and survival. Of the 54 RCC cases studied, 11 (20.4%) showed positive lymph node involvement while 43 (79.6%) were lymph node negative. There was no difference in nm23 protein expression between cases with and without lymph node involvement. In addition, nm23 protein expression was not related to TNM stage, Fuhrman nuclear grade or survival. More extensive studies are required to understand the effect of nm23 protein expression on the biological behaviour of RCC.

Identification of nuclear localization sequence of CXCR4 in renal cell carcinoma by constructing expression plasmids of different deletants

We previously firstly discovered that CXCR4 nuclear localization may be responsible for metastasis of renal cell carcinoma (RCC), and that there was a nuclear localization sequence (NLS) that induced CXCR4 to transfer to the nucleus after combining with its ligand SDF-1. Using our previously constructed pEGFP-CXCR4 as the template, corresponding objective regions were amplified. The amplified PCR products were then digested and inserted into the pMD19-T simple vector and subcloned into the pEGFP-N1 vector. A recombinant expression vector containing different regions of CXCR4 was successfully constructed. After transfecting the recombinant expression vectors to RCC A498 cells, the intracellular locations of recombinant protein were examined by confocal microscopy. It was found that nuclear localization sequence of CXCR4 was located in amino acids 90-170, which accorded with the results of bioinformatics analysis software. The present study firstly discovered the NLS region of CXCR4, which may prove valuable for seeking new strategies to inhibit metastasis of RCC.