The significance of thymidine phosphorylase/platelet-derived endothelial cell growth factor activity in renal cell carcinoma

Pre-treatment systemic immune-inflammation index as a non-invasive biomarker for predicting clinical outcomes in patients with renal cell carcinoma: a meta-analysis of 20 studies

INTRODUCTION

To systematically assess the predictive significance of systemic immune-inflammation index (SII) in renal cell carcinoma (RCC).

METHODS

Relevant studies published before November 2022 were retrieved from public databases. Hazard ratio (HR), standardised mean difference (SMD) and relative risk (RR) were calculated to estimate associations of SII with prognosis, treatment responses and clinicopathological features.

RESULTS

Twenty studies involving 6887 patients were eligible. The meta-analysis results revealed a high SII level was associated with worse overall survival (HR: 1.45, p < 0.001), progression-free survival (HR: 1.63, p = 0.001), cancer-specific survival (HR: 1.86, p < 0.001), lower overall response rate (RR: 0.62, p = 0.003), disease control rate (RR: 0.69, p = 0.002), larger tumour size (SMD: 0.39, p = 0.001), poorer IMDC risk (RR: 7.09, p < 0.001), higher Fuhrman grade (RR: 1.54, p = 0.004), tumour stage (RR: 1.67, p = 0.045), the presence of distant metastasis (brain: RR, 2.04, p = 0.001; bone: RR, 1.33, p = 0.024) and tumour necrosis (RR: 1.57, p = 0.031). Subgroup analysis showed SII predicted OS and PFS for non-Asian, but CSS for both Asian and non-Asian populations.

CONCLUSION

Pre-treatment SII may be a promising predictor of clinical outcomes for RCC patients.

The Platelet Response to Tissue Injury

In recent years, various studies have increasingly explained platelet functions not only in their central role as a regulator in cellular hemostasis and coagulation. In fact, there is growing evidence that under specific conditions, platelets act as a mediator between the vascular system, hemostasis, and the immune system. Therefore, they are essential in many processes involved in tissue remodeling and tissue reorganization after injury or inflammatory responses. These processes include the promotion of inflammatory processes, the contribution to innate and adaptive immune responses during bacterial and viral infections, the modulation of angiogenesis, and the regulation of cell apoptosis in steady-state tissue homeostasis or after tissue breakdown. All in all platelets may contribute to the control of tissue homeostasis much more than generally assumed. This review summarizes the current knowledge of platelets as part of the tissue remodeling network and seeks to provide possible translational implications for clinical therapy.

Lower mean platelet volume predicts poor prognosis in renal cell carcinoma

Altered mean platelet volume (MPV) is found in several malignancies. Remarkably, there is little consensus on using the value of MPV in the prognostic evaluations of renal cell carcinoma (RCC). The aim of this study is to examine the feasibility of MPV value as a prognostic indicator of RCC. The retrospective study recruited 306 consecutive RCC patients between January 2009 and December 2009. The relationships between MPV and clinicopathological characteristics were analyzed. Kaplan-Meier method and Cox regression were used to evaluate the prognostic impact of MPV. Of the 306 RCC patients, low MPV levels were detected in 61 (19.9%) patients. Reduced MPV was associated with histology types, T classification, UCLA Integrated Scoring System (UISS) category, and Mayo clinic stage, size, grade, and necrosis score (SSIGN) category (P < 0.05). Patients with decreased MPV had significantly shorter survival time than patients with normal MPV (P < 0.001). Cox regression analysis revealed that reduced MPV was an independent prognostic factor for overall survival (hazard ratio, 1.758; 95% confidence interval [CI], 1.083–2.855, P = 0.023). Moreover, the prognostic accuracy of TNM stage, UISS, and SSIGN prognostic models were improved when MPV was added. In conclusion, reduced MPV is identified as an independent predictor of adverse clinical outcome in RCC.

Association of decreased mean platelet volume with renal cell carcinoma

BACKGROUND

Renal cell carcinoma (RCC) is the third most common genitourinary cancer. Activated platelets play a pivotal role in cancer development and progression. Altered mean platelet volume (MPV) has been reported in several malignancies. The aim of the present study was to investigate the association of MPV with RCC.

STUDY DESIGN

The study consisted of 145 patients with RCC, 110 patients with benign renal tumor and 132 healthy control subjects between January 2015 and December 2015. All participants' clinical and laboratory characteristics at initial diagnosis were collected. The odds ratios (ORs) for RCC were calculated using multivariate logistic regression analysis after adjusting for confounding variables across MPV quartiles.

RESULTS

The patients with RCC had decreased pre-operative MPV compared to the patients with benign renal tumor and healthy control subjects. Furthermore, pre-operative MPV was reduced in benign renal tumor compared with healthy control subjects. Surgical tumor resection resulted in a significant increase in MPV levels (8.7 fL vs. 9.0 fL; p = 0.011). After adjusting for other risk factors, the ORs (95% CIs) for RCC in each MPV quartile were 25.725 (7.556-87.585), 7.447 (2.701-20.537), 0.703 (0.245-2.019), and 1.000, respectively.

CONCLUSIONS

RCC patients have remarkably reduced MPV compared to patients with benign renal tumor and healthy control subjects. Moreover, decreased MPV was independently associated with RCC. Our results suggest that detection of MPV may be useful to assess the risk of RCC.

Progression of Human Renal Cell Carcinoma via Inhibition of RhoA-ROCK Axis by PARG1

Renal cell carcinoma (RCC) is the most lethal urological malignancy with high risk of recurrence; thus, new prognostic biomarkers are needed. In this study, a new RCC antigen, PTPL1 associated RhoGAP1 (PARG1), was identified by using serological identification of recombinant cDNA expression cloning with sera from RCC patients. PARG1 protein was found to be differentially expressed in RCC cells among patients. High PARG1 expression is significantly correlated with various clinicopathological factors relating to cancer cell proliferation and invasion, including G3 percentage (P = .0046), Ki-67 score (p expression is also correlated with high recurrence of N0M0 patients (P = .0084) and poor prognosis in RCC patients (P = .0345). Multivariate analysis has revealed that high PARG1 expression is an independent factor for recurrence (P = .0149) of N0M0 RCC patients. In in vitro studies, depletion of PARG1by siRNA in human RCC cell lines inhibited their proliferation through inducing G1 cell cycle arrest via upregulation of p53 and subsequent p21^Cip1/Waf1, which are mediated by increased RhoA-ROCK activities. Similarly, PARG1 depletion cells inhibited invasion ability via increasing RhoA-ROCK activities in the RCC cell lines. Conversely, overexpression of PARG1 on human embryonic kidney cell line HEK293T promotes its cell proliferation and invasion. These results indicate that PARG1 plays crucial roles in progression of human RCC in increasing cell proliferation and invasion ability via inhibition of the RhoA-ROCK axis, and PARG1 is a poor prognostic marker, particularly for high recurrence of N0M0 RCC patients.

Thymidine kinase and cancer monitoring

Thymidine kinases (TK) have a key function in the synthesis of DNA. Two isoenzymes have been characterized: TK1 is cell cycle-dependent and present in the cytoplasm whereas TK2--located in mitochondria--is cell cycle-independent. The diagnostic and prognostic role of TK1 has recently been investigated. TK1 might be helpful for screening and monitoring of human malignancies. TK1 may also serve as a prognostic factor for progression. Herein, we summarize the status of TK1 for cancer monitoring and point out its use as a proliferation marker. A comprehensive overview about the association of TK-1 with various entities is given.

The dual role of thymidine phosphorylase in cancer development and chemotherapy

Thymidine phosphorylase (TP), also known as "platelet-derived endothelial cell growth factor" (PD-ECGF), is an enzyme, which is upregulated in a wide variety of solid tumors including breast and colorectal cancers. TP promotes tumor growth and metastasis by preventing apoptosis and inducing angiogenesis. Elevated levels of TP are associated with tumor aggressiveness and poor prognosis. Therefore, TP inhibitors are synthesized in an attempt to prevent tumor angiogenesis and metastasis. TP is also indispensable for the activation of the extensively used 5-fluorouracil prodrug capecitabine, which is clinically used for the treatment of colon and breast cancer. Clinical trials that combine capecitabine with TP-inducing therapies (such as taxanes or radiotherapy) suggest that increasing TP expression is an adequate strategy to enhance the antitumoral efficacy of capecitabine. Thus, TP plays a dual role in cancer development and therapy: on the one hand, TP inhibitors can abrogate the tumorigenic and metastatic properties of TP; on the other, TP activity is necessary for the activation of several chemotherapeutic drugs. This duality illustrates the complexity of the role of TP in tumor progression and in the clinical response to fluoropyrimidine-based chemotherapy.

Differential protein expressions in renal cell carcinoma: new biomarker discovery by mass spectrometry

Renal cell carcinoma (RCC) is the most common neoplasm in the adult kidney. Unfortunately, there are currently no biomarkers for the diagnosis of RCC. In addition to early detection, biomarkers have a potential use for prognosis, for monitoring recurrence after treatment, and as predictive markers for treatment efficiency. In this study, we identified proteins that are dysregulated in RCC, utilizing a quantitative mass spectrometry analysis. We compared the protein expression of kidney cancer tissues to their normal counterparts from the same patient using LC-MS/MS. iTRAQ labeling permitted simultaneous quantitative analysis of four samples (cancer, normal, and two controls) by separately tagging the peptides in these samples with four cleavable mass-tags (114, 115, 116, and 117 Da). The samples were then pooled, and the tagged peptides resolved first by strong cation exchange chromatography and then by nanobore reverse phase chromatography coupled online to nanoelectrospray MS/MS. We identified a total of 937 proteins in two runs. There was a statistically significant positive correlation of the proteins identified in both runs (r(p) = 0.695, p < 0.001). Using a cutoff value of 0.67 fold for underexpression and 1.5 fold for overexpression, we identified 168 underexpressed proteins and 156 proteins that were overexpressed in RCC compared to normal tissues. These dysregulated proteins in RCC were statistically significantly different from those of transitional cell carcinoma and end-stage glomerulonephritis. We performed an in silico validation of our results using different tools and databases including Serial Analysis of Gene Expression (SAGE), UniGene EST ProfileViewer, Cancer Genome Anatomy Project, and Gene Ontology consortium analysis.

Thymidine phosphorylase as a prognostic factor in renal cell carcinoma

The purpose of the current study was to clarify further the clinicopathologic significance of thymidine phosphorylase (TP) expression in renal cell carcinoma (RCC). TP expression was evaluated with immunohistochemistry assays using monoclonal anti-TP antibody in formalin-fixed, paraffin-embedded archived specimens of 70 patients with radically operated nonmetastatic RCC (M0 by TNM classification). Semiquantitative analysis, using a scoring system for staining pattern and staining intensity was used. Univariate analysis showed that the characteristics that carried the prognostic significance for survival were age as continuous characteristic (chi-square log-rank test P = 0.0121), TP expression (P = 0.0061), histologic grade (P < 0.0001), and stage (P = 0.0244). In multivariate analysis (by Cox proportional hazards regression analysis), the factors significant for survival were age (HR 1.09; 95% CI 1.03-1.14), stage (HR 2.76; 95% CI 1.27-6.07), and histologic grade (HR 7.91; 95% CI 2.11-29.7), TP did not show independent significant value (HR 0.68; 95% CI 0.19-2.50). However, TP had strong correlation with histologic grade (P = 0.818). In conclusion, TP expression level in RCC is strongly correlated with histologic grade, which is one of well-known prognostic factors in RCC, but TP had no independent prognostic value.

Phase II trial of capecitabine and rHu-interferon-alpha-2a in patients with metastatic renal cell carcinoma, limited efficacy, and moderate toxicity

BACKGROUND

Capecitabine is an orally administered fluoropyrimidine that is converted to 5-fluorouracil by thymidine phosphorylase. In view of the recognized synergism of fluoropyrimidines with interferon-alpha (IFNalpha), a Phase II study to characterize the toxicity and efficacy of the combination of capecitabine and rHuIFNalpha-2a for the treatment of patients with renal cell carcinoma (RCC) was conducted.

PATIENTS AND METHODS

Eligible patients had metastatic RCC, measurable disease, and no prior systemic therapy. A total of 32 patients were entered into the study. Histologic subtypes included clear cell (n = 28) and nonclear cell (n = 2). Histology was unknown for 2 patients. The first 14 patients were treated with capecitabine 1,000 mg/m(2) twice daily on days 1-14 and 22-36, combined with IFNalpha-2a 3.0 MU/m(2) subcutaneously 3 times weekly. Because of toxicity requiring dose reductions during the first cycle, the capecitabine dose was reduced to 825 mg/m(2) twice daily on days 1-14 and 22-36 in the subsequent 18 patients.

RESULTS

Responses were seen in 4 of 32 patients (12%) (95% confidence interval 4% to 29%), with 1 complete response and 3 partial responses. There were 3 responses that occurred at the higher capecitabine starting dose level. Median response duration was 12 months (range 4.6-15.0). There were 12 patients (38%) who had stable disease for at least 2 cycles (duration 2.9 to 33.6+ months). One-year survival was 63%. Toxicity was moderate to severe and required dose reductions in 88% of patients. There were 23 patients who had grade > or =3 toxicity.

CONCLUSION

The combination of capecitabine and IFNalpha-2a has limited activity in metastatic RCC and is associated with moderate-to-severe toxicity.

High levels of thymidine phosphorylase as an independent prognostic factor in renal cell carcinoma

BACKGROUND

We investigated whether thymidine phosphorylase (TP) protein level in renal cell carcinoma (RCC) correlates with clinicopathological characteristics and clinical outcomes.

METHODS

TP protein level was measured in 116 RCC specimens and in 90 non-neoplastic kidney tissues using a sandwich-type enzyme-linked immunosolvent assay.

RESULTS

The median TP protein level in RCC tissues was 9.76-fold (range, 3.2-933.9) higher than those in non-neoplastic kidney tissues (P < 0.0001). TP protein level was correlated with T classification, histological grade and mode of infiltration. TP as a prognostic variable was studied using a logistic regression model. TP at higher levels (128 U/mg protein or greater) would play a role as an independent prognostic factor (odds ratio, 13.73; 95% confidence interval, 2.09-90.41; P = 0.0064).

CONCLUSION

TP at high levels can be regarded as an unfavorable independent prognostic factor. These results may pave a way for a novel approach to effective treatment of RCC.

Gene signatures of progression and metastasis in renal cell cancer

PURPOSE

To address the progression, metastasis, and clinical heterogeneity of renal cell cancer (RCC).

EXPERIMENTAL DESIGN

Transcriptional profiling with oligonucleotide microarrays (22,283 genes) was done on 49 RCC tumors, 20 non-RCC renal tumors, and 23 normal kidney samples. Samples were clustered based on gene expression profiles and specific gene sets for each renal tumor type were identified. Gene expression was correlated to disease progression and a metastasis gene signature was derived.

RESULTS

Gene signatures were identified for each tumor type with 100% accuracy. Differentially expressed genes during early tumor formation and tumor progression to metastatic RCC were found. Subsets of these genes code for secreted proteins and membrane receptors and are both potential therapeutic or diagnostic targets. A gene pattern ("metastatic signature") derived from primary tumor was very accurate in classifying tumors with and without metastases at the time of surgery. A previously described "global" metastatic signature derived by another group from various non-RCC tumors was validated in RCC.

CONCLUSION

Unlike previous studies, we describe highly accurate and externally validated gene signatures for RCC subtypes and other renal tumors. Interestingly, the gene expression of primary tumors provides us information about the metastatic status in the respective patients and has the potential, if prospectively validated, to enrich the armamentarium of diagnostic tests in RCC. We validated in RCC, for the first time, a previously described metastatic signature and further showed the feasibility of applying a gene signature across different microarray platforms. Transcriptional profiling allows a better appreciation of the molecular and clinical heterogeneity in RCC.