p53 and HER-2 alterations in renal cell carcinoma

Prognostic and Predictive Roles of HER2 Status in Non-Breast and Non-Gastroesophageal Carcinomas

The oncogene ERBB2, also known as HER2 or c-ERB2, is located on chromosome 17 (q12). It encodes a tyrosine kinase receptor, the human epidermal growth factor receptor 2 (HER2), involved in neoplastic proliferation, tumor angiogenesis, and invasiveness. Over the past years, the introduction of various anti-HER2 therapies has significantly improved outcomes for patients with HER2-positive breast and gastroesophageal carcinomas. More recently, the introduction of a new antibody-drug conjugate, that is trastuzumab deruxtecan, expanded the therapeutic options to low-HER2 breast and gastroesophageal tumors. HER2 protein overexpression is investigated using immunohistochemistry, gene amplification using fluorescence in situ hybridization, and gene mutation using next-generation sequencing. This review evaluated the predictive and prognostic role of HER2 status in various types of epithelial malignant cancers beyond breast and gastroesophageal cancers. We critically analyzed the key published studies, focusing on utilized scoring systems and assays used, and analyzed clinical parameters and therapeutic approaches. Although the evidence about prognostic and predictive roles of HER2 in carcinomas other than breast and gastroesophageal has been widely increasing over the last decade, it still remains investigational, revealing a tumor site-related prognostic and predictive value of the different types of HER2 alterations. However, standardized and validated scoring system assays have not been well-established for many organs.

Advances in immune-based therapies of renal cell carcinoma

Renal cell carcinoma (RCC) is the most prevalent malignancy within the kidney, and over 40% of patients with RCC will die from their disease. Approximately a third of patients present with metastatic disease and a third of patients undergoing nephrectomy for clinically localized RCC will develop metastases. Metastatic RCC poses a therapeutic challenge due to its resistance to conventional modes of therapy such as chemotherapy and radiation therapy. While it is clear that strides have been made against metastatic RCC, the overall objective response rates of interleukin-2- and interferon-alpha-based immunotherapy remain at approximately 20%. Despite advances in biologic- and immune-based therapies, long-term survival for patients with metastatic RCC remains modest. Furthermore, the toxicity profile of these cytokine regimens is significant. Advances in the understanding of the nature of tumor antigens and their optimal presentation, and in the regulatory mechanisms that govern the immune system, have provided multiple novel immunotherapy intervention strategies with increased specificity and potentially fewer side effects. Such strategies are currently being tested in clinical trials.

HER2 expression in renal cell carcinoma is rare and negatively correlated with that in normal renal tissue

The aim of this study was to evaluate the status of HER2 protein expression in patients with renal cell carcinoma (RCC) and to determine its prognostic significance. A total of 42 paraffin-embedded tumor tissues and 42 additional corresponding adjacent normal tissues from RCC patients were randomly collected and studied using immunohistochemistry (IHC). Protein samples of 6 fresh specimens from tumor and adjacent normal tissues obtained during surgery were extracted and tested using western blotting to confirm the IHC results. Of the 42 tumor tissues and adjacent normal tissues tested, IHC showed that 7 tumors (16.67%) and 33 adjacent normal tissues (78.57%) expressed the HER2 protein. In addition, results of the western blotting revealed weak HER2 reactivity in primary tumor cells in two of 6 specimens obtained during surgery. All 6 normal tissues showed positive expression, which was in accordance with the outcome of IHC. In conclusion, HER2 is frequently expressed in normal renal tissues and rarely expressed in RCC tissues. Furthermore, the HER2 status of normal tissue is negatively correlated with that of the RCC tissues (r=-0.410, P=0.007) and the TNM stage (r=-0.246, P=0.027), suggesting that HER2 is involved in RCC oncogenesis.

p53 and MDM2 in renal cell carcinoma: biomarkers for disease progression and future therapeutic targets?

Renal cell carcinoma (RCC) is the most common type of kidney cancer and follows an unpredictable disease course. To improve prognostication, a better understanding of critical genes associated with disease progression is required. The objective of this review was to focus attention on 2 such genes, p53 and murine double minute 2 (MDM2), and to provide a comprehensive summary and critical analysis of the literature regarding these genes in RCC. Information was compiled by searching the PubMed database for articles that were published or e-published up to April 1, 2009. Search terms included renal cancer, renal cell carcinoma, p53, and MDM2. Full articles and any supplementary data were examined; and, when appropriate, references were checked for additional material. All studies that described assessment of p53 and/or MDM2 in renal cancer were included. The authors concluded that increased p53 expression, but not p53 mutation, is associated with reduced overall survival/more rapid disease progression in RCC. There also was evidence that MDM2 up-regulation is associated with decreased disease-specific survival. Two features of RCC stood out as unusual and will require further investigation. First, increased p53 expression is tightly linked with increased MDM2 expression; and, second, patients who have tumors that display increased p53 and MDM2 expression may have the poorest overall survival. Because there was no evidence to support the conclusion that p53 mutation is associated with poorer survival, it seemed clear that increased p53 expression in RCC occurs independent of mutation. Further investigation of the mechanisms leading to increased p53/MDM2 expression in RCC may lead to improved prognostication and to the identification of novel therapeutic interventions.

Clear cell adenocarcinoma of the colon: A case report and review of literature

A primary clear cell adenocarcinoma of the colon is a rare oncologic entity. We herein report a case of such a tumor of the sigmoid colon in a 71-year-old woman who was successfully treated by an endoscopic polypectomy in our hospital. We also reviewed the published reports regarding cases of primary clear cell tumors in the colon.

ErbB receptors and epithelial-cadherin-catenin complex in human carcinomas

The ErbB family of receptor tyrosine kinases have important roles in maintaining normal epithelial cell function. The ErbBs are involved in the interaction between cells and cell-matrix adhesion molecules and have proven critical in maintaining the integrity of the epithelial cell environment. Deregulation of these tyrosine receptors has been associated with several human diseases. In particular, the expression or activation of epidermal growth factor receptor (EGFR) and ErbB2 is altered in many epithelial tumors. Epithelial (E)-cadherin is another major molecule expressed by epithelial cells. To create efficient cell-cell adhesion, E-cadherin couples its cytoplasmic domain to catenins and the actin cytoskeleton. The loss of intercellular adhesion appears to be a fundamental aspect of the neoplastic phenomena. In addition, EGFR and ErbB2 signaling associated with the E-cadherin-catenin complex has been demonstrated in normal and cancer cells. This signaling is involved in regulating cell adhesion and the invasive growth of cancers. This article provides an overview of the interaction between the ErbB tyrosine receptors and the E-cadherin-catenin complex in human carcinomas.

Value of p53 as a prognostic marker in histologic subtypes of renal cell carcinoma: a systematic analysis of primary and metastatic tumor tissue

OBJECTIVES

To investigate the histologic subtypes of renal cell carcinoma (RCC) with respect to differences in immunoreactivity for p53 and its impact on prognosis. The prognostic significance of p53 in RCC remains to be defined.

METHODS

A total of 188 primary RCC and 58 RCC metastasis specimens were stained immunohistochemically for p53 overexpression using a tissue microarray technique. p53 overexpression was analyzed semiquantitatively with respect to its association with pT stage, grade, histologic subtype, and sex using the chi-square test or Fisher's exact test. The impact on metastasis-free survival was analyzed using the Kaplan-Meier method and log-rank test. For conventional RCC, a multivariate analysis, including pT stage, grade, and p53 immunoreactivity was performed.

RESULTS

Sufficient tumor tissue was present in 184 (97.9%) of 188 primary and 56 (96.6%) of 58 metastatic cases. p53 overexpression was found in 42 (22.8%) of 184 primary RCC specimens and in 29 (51.8%) of 56 metastasis specimens (P = 0.0001). p53 overexpression for papillary, chromophobe, and conventional RCC was 70.0%, 27.3%, and 11.9%, respectively (P <0.0001). No association of p53 immunoreactivity with the other parameters investigated was found. Regarding prognosis, a statistically significant difference in metastasis-free survival between p53-positive and p53-negative tumors was found only for conventional RCC (P = 0.0005) and not for the other subtypes (P = 0.19). Multivariate analysis proved grade (P <0.0001), pT stage (P = 0.01), and p53 overexpression (P = 0.01) to be independent prognostic factors for conventional RCC.

CONCLUSIONS

p53 overexpression was significantly more frequent in "nonconventional" RCC subtypes, especially papillary RCC, compared with conventional RCC in our study. However, p53 immunoreactivity is a prognostic marker only for conventional RCC.

Renal-cell carcinoma: tumour markers, T-cell epitopes, and potential for new therapies

Advanced renal-cell carcinoma is a very difficult tumour to treat, and response rates to biological therapies are less than 20%. The identification of various molecular and cellular markers has led to the development of novel therapies. Despite evaluation of their association with histological subtype, immune infiltration, molecular markers of cell proliferation, p53 mutation, and growth-factor-receptor expression, none of these markers has proved better predictive factors than tumour stage and histological grade. The identification of tumour-associated antigens and the specificity of cellular immune responses have led to the development of targeted immunotherapy with monoclonal antibodies, radioimmunotherapy, and T-cell therapies. In this review, we evaluate a range of markers associated with renal-cell carcinoma and new treatment approaches based on tumour-associated antigens and, in particular, T-cell epitopes.

Distinct tyrosine autophosphorylation sites mediate induction of epithelial mesenchymal like transition by an activated ErbB-2/Neu receptor

Tight control of cell proliferation and morphogenesis is required to ensure normal tissue patterning and prevent cancer formation. Overexpression of the ErbB-2/Neu receptor tyrosine kinase is associated with increased progression in human breast cancer, yet in breast explant cultures, the ErbB-2/Neu receptor contributes to alveolar differentiation. To examine the consequence of deregulated ErbB-2/Neu activation on epithelial morphogenesis, we have expressed a constitutively activated mutant of ErbB-2/Neu in a Madin-Darby canine kidney (MDCK) epithelial cell model. Using two-dimensional cultures we demonstrate that activated ErbB-2/Neu induces breakdown of cell-cell junctions, increased cell motility and dispersal of epithelial colonies. This correlates with reorganization of the actin cytoskeleton and focal adhesions and loss of insoluble cell-cell junction complexes involving E-cadherin. Interestingly, a constitutively activated ErbB-2/Neu receptor promotes an invasive morphogenic program in MDCK cells in a three-dimensional matrix. We show that two tyrosines in the carboxy-terminal tail of ErbB-2/Neu, involved in the phosphorylation of the Shc adapter protein, are each sufficient to promote epithelial-mesenchymal like transition and enhanced cell motility in two-dimensional culture and cell invasion rather than a morphogenic response in matrix culture. This provides a model system to investigate ErbB-2/Neu induced signaling pathways required for epithelial cell dispersal and invasion versus morphogenesis.

p53 expression in correlation to clinical outcome in patients with renal cell carcinoma

OBJECTIVE

The aim of this study was to evaluate the role of p53 as prognostic factor in renal cell carcinoma (RCC) and its relation to clinicopathological factors.

MATERIAL AND METHODS

The nuclear accumulation of p53 protein was determined by immunohistochemical analysis in RCC specimens from 90 patients and was correlated with clinical stage, grade, DNA ploidy, S-phase fraction and cancer-specific survival.

RESULTS

p53 overexpression was observed in 17 of 90 (19%) tumours. There was a significant correlation to stage (p = 0.016) and grade (p = 0.020) but not to DNA ploidy or S-phase. Patients with high p53 immunoreactivity had shorter cancer-specific survival (p = 0.003) than those with normal p53 protein expression. This difference was found in papillary and chromophobe tumour types (p < 0.0001) but not in conventional RCC.

CONCLUSIONS

In patients with RCC, significant correlations between p53 protein expression and tumour stage, grade and survival time were observed. For patients with chromophobe and papillary tumour types, but not in conventional RCC, p53 immunoreactivity gave prognostic information, suggesting that the prognostic differences in p53 immunoreactivity might be due to disparate genetic abnormalities in the different RCC types.

Value of immunohistochemical Ki-67 and p53 determinations as predictive factors of outcome in renal cell carcinoma

OBJECTIVES

Nuclear grade and tumor stage are important prognostic factors in renal cell carcinoma, but tumors of similar stage and grade can exhibit a wide variation in biologic behavior and clinical outcome. In this retrospective study, we evaluated the immunologic markers, Ki-67 (MIB1) and p53, in 73 cases of conventional (clear cell) renal cell carcinoma and compared these markers with the accepted prognostic features of grade, stage, and tumor size in predicting outcome.

METHODS

Specimens of 73 renal cell carcinomas of different nuclear grade (20 Furhman I/II, 32 Fuhrman III, and 21 Fuhrman IV) and different stage (10 pT1, 23 pT2, 36 pT3, and 4 pT4) were immunostained with monoclonal antibodies against Ki-67 and p53.

RESULTS

Univariate statistical analysis showed that tumor size (P <0. 001), nuclear grade (P <0.01), tumor stage (P <0.01), Ki-67 index (P <0.001), and p53 immunostaining (P <0.03) correlated significantly with a poor prognosis. A Ki-67 index of 20% was a powerful predictor of survival in all patients (P <0.00001), with strong predictive values. On multivariate analysis, the Ki-67 index and metastases were significant independent prognostic factors (P <0.02 and <0.01, respectively).

CONCLUSIONS

Ki-67 immunostaining appeared to be an additional prognostic indicator of biologic aggressiveness in renal cell carcinoma. Immunohistochemical assessment of tumor antigens could be used to identify patients at high risk of tumor progression in addition to conventional prognostic factors.