Lower expression levels of the transforming growth factor beta receptor type II protein are associated with a less aggressive tumor phenotype and improved survival among patients with clear cell renal cell carcinoma

Review of Prognostic Expression Markers for Clear Cell Renal Cell Carcinoma

Context: The number of prognostic markers for clear cell renal cell carcinoma (ccRCC) has been increasing regularly over the last 15 years, without being integrated and compared. Objective: Our goal was to perform a review of prognostic markers for ccRCC to lay the ground for their use in the clinics. Evidence Acquisition: PubMed database was searched to identify RNA and protein markers whose expression level was reported as associated with survival of ccRCC patients. Relevant studies were selected through cross-reading by two readers. Evidence Synthesis: We selected 249 studies reporting an association with prognostic of either single markers or multiple-marker models. Altogether, these studies were based on a total of 341 distinct markers and 13 multiple-marker models. Twenty percent of these markers were involved in four biological pathways altered in ccRCC: cell cycle, angiogenesis, hypoxia, and immune response. The main genes (VHL, PBRM1, BAP1, and SETD2) involved in ccRCC carcinogenesis are not the most relevant for assessing survival. Conclusion: Among single markers, the most validated markers were KI67, BIRC5, TP53, CXCR4, and CA9. Of the multiple-marker models, the most famous model, ClearCode34, has been highly validated on several independent datasets, but its clinical utility has not yet been investigated. Patient Summary: Over the years, the prognosis studies have evolved from single markers to multiple-marker models. Our review highlights the highly validated prognostic markers and multiple-marker models and discusses their clinical utility for better therapeutic care.

Identification of prognostic chromatin-remodeling genes in clear cell renal cell carcinoma

The aim of this study was to investigate the effects of chromatin-remodeling genes on the prognosis of patients with clear cell renal cell carcinoma (ccRCC). In TCGA-KIRC patients, two subgroups based on 86 chromatin-remodeling genes were established. The random forest algorithm was used for feature selection to identify BPTF, SIN3A and CNOT1 as characterized chromatin remodelers in ccRCC with good prognostic value. YY1 was indicated to be a transcription factor of genes highly related to BPTF, SIN3A and CNOT1. Functional annotations indicated that BPTF, SIN3A, CNOT1 and YY1 are all involved in the ubiquitin-mediated proteolysis process and that high expression of any of the five associated E3 ubiquitin ligases found in the pathway suggests a good prognosis. Protein network analysis indicated that BPTF has a targeted regulatory effect on YY1. Another independent dataset from International Cancer Genome Consortium (ICGC) showed a strong consistency with results in TCGA. In conclusion, we demonstrate that BPTF, SIN3A and CNOT1 are novel prognostic factors that predict good survival in ccRCC. We predicted that the good prognostic value of chromatin-remodeling genes BPTF and SIN3A is related to the regulation of YY1 and that YY1 regulates E3 ubiquitin ligases for further degradation of oncoproteins in ccRCC.

TGF-β and microRNA Interplay in Genitourinary Cancers

Genitourinary cancers (GCs) include a large group of different types of tumors localizing to the kidney, bladder, prostate, testis, and penis. Despite highly divergent molecular patterns, most GCs share commonly disturbed signaling pathways that involve the activity of TGF-β (transforming growth factor beta). TGF-β is a pleiotropic cytokine that regulates key cancer-related molecular and cellular processes, including proliferation, migration, invasion, apoptosis, and chemoresistance. The understanding of the mechanisms of TGF-β actions in cancer is hindered by the "TGF-β paradox" in which early stages of cancerogenic process are suppressed by TGF-β while advanced stages are stimulated by its activity. A growing body of evidence suggests that these paradoxical TGF-β actions could result from the interplay with microRNAs: Short, non-coding RNAs that regulate gene expression by binding to target transcripts and inducing mRNA degradation or inhibition of translation. Here, we discuss the current knowledge of TGF-β signaling in GCs. Importantly, TGF-β signaling and microRNA-mediated regulation of gene expression often act in complicated feedback circuits that involve other crucial regulators of cancer progression (e.g., androgen receptor). Furthermore, recently published in vitro and in vivo studies clearly indicate that the interplay between microRNAs and the TGF-β signaling pathway offers new potential treatment options for GC patients.

Distinctive features of the differentiated phenotype and infiltration of tumor-reactive lymphocytes in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (RCC) is considered an immunogenic tumor, but it has been difficult to identify tumor-infiltrating lymphocytes (TIL) that show in vitro tumor recognition. We compared the characteristics of fresh RCC TIL to peripheral blood lymphocytes (PBL) or melanoma TIL. Our results showed that RCC TIL contained fewer CD27(+) T cells, and fewer naïve and central memory (CM) T cells, but more effector memory (EM) T cells than melanoma TIL or renal PBL. We hypothesized that factors in the RCC microenvironment were skewing TIL phenotype toward EM. One possibility was the expression of CD70 on nearly all human RCCs, but not melanomas. Differentiation of naïve T cells to EM cells only occurred from CD70 costimulation in concert with T-cell receptor (TCR) stimulation (signal one), suggesting that EM TIL responding to CD70 would be enriched for T cells reactive with local antigens, including those associated with RCC. Clonotypic analysis of TCRs in fresh RCCs showed that EM T cells were more clonally expanded than CM or naïve T cells, and the clonal expansion occurred at the tumor site as oligoclonal TCRs were distinct from PBL TCRs from the same patient. In addition, we found that 2 TCRs from the highly represented EM TIL clones, when reexpressed in fresh PBL, recognized an MHC-class II or MHC-class I-restricted antigens shared by multiple RCC lines. Our results suggest that RCC-reactive TIL do exist in situ, but may be difficult to recover and study because of proliferative exhaustion, driven by tumor-expressed CD70.

Alterations of Smad expression and activation in defining 2 subtypes of human head and neck squamous cell carcinoma

BACKGROUND

We postulated that disruptions of the canonical transforming growth factor-beta (TGF-β)/Smad signaling pathway might contribute to the development of head and neck squamous cell carcinoma (HNSCC).

METHODS

A cohort of 798 HNSCC tumor samples from 346 patients were analyzed by immunohistochemistry (IHC) to define the pattern of expression of (phospho)Smad2, (phospho)Smad3, and Smad4.

RESULTS

We found that 19%, 40%, and 12% of HNSCC specimens failed to express pSmad2, pSmad3, or Smad4, respectively. Loss of Smad2/3 activation was observed in 8.5% of specimens. In addition, 4% of specimens failed to express only Smad4. Moreover, patients with pSmad2/3-negative tumors had a significantly better overall survival than that of those whose tumors expressed activated Smad2/3. In contrast, loss of Smad4 expression did not have prognostic significance.

CONCLUSION

Our results indicate that HNSCC in which Smad2/3 are inactivated or in which Smad4 expression is lost represent 2 distinct tumor subtypes with different clinical outcomes.

The notch and TGF-β signaling pathways contribute to the aggressiveness of clear cell renal cell carcinoma

Background

Despite recent progress, therapy for metastatic clear cell renal cell carcinoma (CCRCC) is still inadequate. Dysregulated Notch signaling in CCRCC contributes to tumor growth, but the full spectrum of downstream processes regulated by Notch in this tumor form is unknown.

Methodology/Principal Findings

We show that inhibition of endogenous Notch signaling modulates TGF-β dependent gene regulation in CCRCC cells. Analysis of gene expression data representing 176 CCRCCs showed that elevated TGF-β pathway activity correlated significantly with shortened disease specific survival (log-rank test, p = 0.006) and patients with metastatic disease showed a significantly elevated TGF-β signaling activity (two-sided Student's t-test, p = 0.044). Inhibition of Notch signaling led to attenuation of both basal and TGF-β1 induced TGF-β signaling in CCRCC cells, including an extensive set of genes known to be involved in migration and invasion. Functional analyses revealed that Notch inhibition decreased the migratory and invasive capacity of CCRCC cells.

Conclusion

An extensive cross-talk between the Notch and TGF-β signaling cascades is present in CCRCC and the functional properties of these two pathways are associated with the aggressiveness of this disease.

In search of a better crystal ball: recent advances in prognostic markers for clear-cell renal cell carcinoma

Advances in imaging have led to a steady increase in the incidence of kidney cancer over the last two decades. There has been no corresponding improvement in our ability to predict the behavior of renal cell carcinoma. Patients with low-risk renal cell carcinoma have good long-term survival with only localized therapy but patients with aggressive disease do poorly, even with optimal multimodal treatment. Biomarkers to differentiate between these two very divergent populations have traditionally been of only limited utility. We review the recent advances in the development of molecular and immunologic markers aimed at improving prognostication of renal cell carcinoma.

Loss of expression of TIMP3 in clear cell renal cell carcinoma

AIMS

In clear cell renal cell carcinoma (CCRCC), vascular endothelial growth factor (VEGF) represents the central positive mediator of tumour angiogenesis while VEGF receptor (VEGFR) is the primary target of anti-angiogenic therapies. TIMP3 is a physiological VEGFR-2 antagonist and thus could be considered as an anti-angiogenic factor. We therefore determined the status of this physiological inhibitor in CCRCC.

PATIENTS AND METHODS

Archival tumour from 105 patients was studied. TIMP3 expression was analysed using immuno-histochemistry and real-time RT-PCR. Results were correlated with clinicopathological variables. To analyse the mechanisms of gene silencing involved, we performed Multiplex Ligation-dependent Probe Amplification (MLPA) and methylation-specific MLPA (MS-MLPA). At last, we evaluated the main upstream pathway described implicating TGFbetaRII, which induces TIMP3 expression.

RESULTS

A down-expression of TIMP3, determined by immunohistochemistry, affected 100/105 renal cancers (95.2%). TIMP3 mRNA levels were significantly lower in high-grade tumours. Loss of heterozygosity of the TIMP3 gene was observed in 8 tumours (7.6%) and the 5'CpG island of the TIMP3 promoter was found to be methylated in 25 tumours (23.8%). A down-expression of TGFbetaRII was found in 85/105 CCRCCs (80.9%). A significant correlation was found between TIMP3 expression and TGFbetaRII expression.

CONCLUSIONS

This is the first demonstration that the loss of TIMP3 expression is observed in almost all CCRCCs. This loss of expression is a common molecular event in CCRCC. It may be an important initiation step for tumour development in a complex process implicating loss of heterozygosity on chromosome 22q, promoter hyper-methylation and inactivation of the TGFbetaRII pathway.

Prognostic markers in renal cell carcinoma

PURPOSE OF REVIEW

This article reviews recent reports on prognostic markers in renal cell carcinoma.

RECENT FINDINGS

Inclusion in studies of larger cohorts of patients has yielded enhanced prognostic information from integrated pathological markers; the findings suggest that adjustment to the TNM (tumour-node-metastasis) system is warranted. A number of patient-related factors remain important prognostically, including performance status, C-reactive protein and thrombocytosis, but also immunological factors (e.g. expression of B7-H1 by renal cell carcinomas is associated with progression). Additional prognostic information may be derived from a range of molecular markers. Findings of gene array and methylation studies may yield independent prognostic information. Enhanced knowledge of signalling pathways has facilitated better understanding of underlying biology and prediction of response to treatment. Other genes involved in regulating hypoxia-inducible factor [e.g. genes encoding carbonic anhydrase-IX and PTEN (phosphatase and tensin homolog)] were reported to be prognostically important in renal cell carcinoma. Other markers independently predicted survival (e.g. thymidine-phosphorylase and survivin).

SUMMARY

The potential of molecular markers suggested by clinical research is encouraging. Knowledge of various pathways will facilitate creation of systems of biomarkers that are predictive of individual response to therapy. Useful biomarkers may have potential as therapeutic targets.