Tumor Microvessel Density as a Prognostic Marker in High-Risk Renal Cell Carcinoma Patients Treated on ECOG-ACRIN E2805.

Purpose: Increased vascularity is a hallmark of renal cell carcinoma (RCC). Microvessel density (MVD) is one measurement of tumor angiogenesis; however, its utility as a biomarker of outcome is unknown. ECOG-ACRIN 2805 (E2805) enrolled 1,943 resected high-risk RCC patients randomized to adjuvant sunitinib, sorafenib, or placebo. We aimed to determine the prognostic and predictive role of MVD in RCC.Experimental Design: We obtained pretreatment primary RCC nephrectomy tissues from 822 patients on E2805 and constructed tissue microarrays. Using quantitative immunofluorescence, we measured tumor MVD as the area of CD34-expressing cells. We determined the association with disease-free survival (DFS), overall survival (OS), treatment arm, and clinicopathologic variables.Results: High MVD (above the median) was associated with prolonged OS for the entire cohort (P = 0.021) and for patients treated with placebo (P = 0.028). The association between high MVD and OS was weaker in patients treated with sunitinib or sorafenib (P = 0.060). MVD was not associated with DFS (P = 1.00). On multivariable analysis, MVD remained independently associated with improved OS (P = 0.013). High MVD correlated with Fuhrman grade 1-2 (P < 0.001), clear cell histology (P < 0.001), and absence of necrosis (P < 0.001) but not with gender, age, sarcomatoid features, lymphovascular invasion, or tumor size.Conclusions: High MVD in resected high-risk RCC patients is an independent prognostic, rather than predictive, biomarker of improved OS. Further studies should assess whether incorporating MVD into clinical models will enhance our ability to predict outcome and if low MVD can be used for selection of high-risk patients for adjuvant therapy trials. Clin Cancer Res; 24(1); 217-23. ©2017 AACR.

Characterization of tumor infiltrating lymphocytes in paired primary and metastatic renal cell carcinoma specimens.

Renal cell carcinoma (RCC) is one of the most chemo- and radio-resistant malignancies, with poor associated patient survival if the disease metastasizes. With recent advances in immunotherapy, particularly with PD-1/PD-L1 blockade, outcomes are improving, but a substantial subset of patients does not respond to the new agents. Identifying such patients and improving the therapeutic ratio has been a challenge, although much effort has been made to study PD-1/PD-L1 status in pre-treatment tumor. However, tumor infiltrating lymphocyte (TIL) content might also be predictive of response, and our goal was to characterize TIL content and PD-L1 expression in RCC tumors from various anatomic sites. Utilizing a quantitative immunofluorescence technique, TIL subsets were examined in matched primary and metastatic specimens. In metastatic specimens, we found an association between low CD8+ to Foxp3+ T-cell ratios and high levels of PD-L1. High PD-L1-expressing metastases were also found to be associated with tumors that were high in both CD4+ and Foxp3+ T-cell content. Taken together these results provide the basis for combining agents that target the PD-1/PD-L1 pathway with agonist of immune activation, particularly in treating RCC metastases with unfavorable tumor characteristics and microenvironment. In addition, CD8+ TIL density and CD8:Foxp3 T-cell ratio were higher in primary than metastatic specimens, supporting the need to assess distant sites for predictive biomarkers when treating disseminated disease.

PAX-8 expression in renal tumours and distant sites: a useful marker of primary and metastatic renal cell carcinoma?

AIMS: Immunohistochemical stains have greatly improved the diagnostic accuracy of renal cell carcinoma (RCC) for primary and distant tumours. We evaluate a marker that has recently been incorporated in clinical practice, PAX-8, in primary and metastatic RCCs. METHODS: Two distinct tissue microarrays were used, one consisting of over 334 renal tumours, 294 with adjacent normal kidney and the other with 40 matched nephrectomy and metastatic sites of RCC. PAX-8 expression was assessed by a method of quantitative immunofluorescence. RESULTS: PAX-8 was positive in 96% (146/152) of normal renal tissue and 83% (227/272) of renal tumours. PAX-8 staining was positive in clear cell, papillary and chromophobe tumours in 80% (165/207), 95% (39/41) and 100% (6/6) of samples, respectively. Overall, intensity of PAX-8 expression was significantly higher in RCC metastatic sites than in the primary site (p=0.0047), however, in matched sites there was no statistically significant difference in the proportion of positive versus negative specimens (p=0.274). CONCLUSIONS: As the role of molecular markers expands in the diagnostic algorithm, this study confirms that PAX-8 expression is a useful diagnostic marker for RCC. PAX-8 expression was found in the primary tumour and distant sites. Compared with normal tissue and other histological types, clear cell RCC has lower PAX-8 expression and is less frequently positive, therefore, the lack of expression does not exclude a tumour of renal origin.

NY-ESO-1 as a potential immunotherapeutic target in renal cell carcinoma.

BACKGROUND: Novel immune therapies targeting tumor specific antigens are being developed. Our purpose was to determine expression of the cancer testes antigen NY-ESO-1 in renal cell carcinoma (RCC), as NY-ESO-1 targeting approaches, particularly adoptive cell therapy, have not been evaluated in this disease. METHODS: We employed tissue microarrays containing >300 unique RCC cases and adjacent benign renal tissue to determine NY-ESO-1 expression using a quantitative immunofluorescence method. In addition, we studied NY-ESO-1 expression in 35 matched primary and metastatic RCC specimens to assess concordance between different tumor sites. RESULTS: NY-ESO-1 was highly expressed in a subset of RCCs. Expression in primary RCC specimens was significantly higher than adjacent normal renal tissue (P<0.0001) and higher in clear cell carcinomas than papillary RCC (P<0.0001). Expression levels in metastatic specimens were higher than in matched primary samples (P=0.0018), and the correlation between the two sites was modest (χ2=3.5, p=0.06). CONCLUSIONS: Aberrant NY-ESO-1 expression seen in clear cell RCC suggests that NY-ESO-1 targeting approaches should be studied in this disease. Expression is higher in metastatic sites, and discordance between primary and metastatic sites in some patients suggests that patient selection for these therapies should be based on expression in metastatic rather than nephrectomy specimens.

Microvessel area as a predictor of sorafenib response in metastatic renal cell carcinoma.

BACKGROUND: Sorafenib was the first Food and Drug Administration approved anti-angiogenic therapy for renal cell carcinoma (RCC). Currently, there are no validated predictive biomarkers for sorafenib. Our purpose was to determine if sorafenib target expression is predictive of sorafenib sensitivity. METHODS: We used an automated, quantitative immunofluorescence-based method to determine expression levels of sorafenib targets VEGF, VEGF-R1, VEGF-R2, VEGF-R3, c-RAF, B-RAF, c-Kit, and PDGFR-ß in a cohort of 96 patients treated with sorafenib. To measure vasculature in the tumor samples, we measured microvessel area (MVA) by CD-34 staining. RESULTS: Of the markers studied, only high MVA was predictive of response (p = 0.005). High MVA was associated with smaller primary tumors (p = 0.005). None of the biomarkers studied was predictive of overall or progression-free survival. Using the Bonferroni adjustment correcting for 9 variables with an alpha of 0.05, MVA remained significantly associated with sorafenib response. CONCLUSIONS: Our results suggest that high MVA in tumor specimens might be associated with a greater likelihood of response to therapy. Further studies are needed to confirm these results in additional patients and in patients receiving other VEGF-R2 inhibitors, as MVA might be useful to improve patient selection for VEGF-R2 inhibitors.

Expression of drug targets in primary and matched metastatic renal cell carcinoma tumors.

BACKGROUND: Targeted therapies in renal cell carcinoma can have different effects on primary and metastatic tumors. To pave the way for predictive biomarker development, we assessed differences in expression of targets of currently approved drugs in matched primary and metastatic specimens from 34 patients. METHODS: Four cores from each site were embedded in tissue microarray blocks. Expression of B-Raf, C-Raf, cKIT, FGF-R1, HIF-2α, mTOR, PDGF-Rß, VEGF-R1, VEGF-R2, VEGF-R3, VEGF, VEGF-B, VEGF-C, VEGF-D, MEK1, and ERK1/2 was studied using a quantitative immunofluorescence method. RESULTS: No significant differences were observed in global expression levels in primary and metastatic renal cell carcinoma tumors, with the exception of MEK, which had higher expression in metastatic than primary specimens. Similarly, more ki67 positive cells were seen in metastatic specimens. Correlations between marker expression in primary and metastatic specimens were variable, with the lowest correlation seen for FGF-R1 and VEGF-D. There were no significant differences in the degree of heterogeneity in primary versus metastatic tumors. CONCLUSIONS: Expression of most of the studied markers was similar in primary and metastatic renal cell carcinoma tumors, suggesting that predictive biomarker testing for these markers can be conducted on either the primary or metastatic tumors for most markers.

Vascularity of primary and metastatic renal cell carcinoma specimens.

PURPOSE: Anti-angiogenic therapies are among the most commonly used drugs in renal cell carcinoma. Tumor vascularity, defined by microvessel area, may be associated with response to these drugs. Clinical studies suggest that metastatic sites are more responsive than primary tumors. Our purpose was to characterize microvessel area (MVA) in matched primary and metastatic samples and in samples of different histologies. METHODS: We employed a method of automated, quantitative analysis of in situ tumor components to identify the area of CD-34 staining endothelial cells within renal cell carcinoma tumors. MVA was assessed in corresponding primary and metastatic samples from 34 patients, as well as in 334 primary nephrectomy specimens with variable histologies. RESULTS: MVA measurements from different parts of the same tumor correlated well (R = 0.75), indicating that MVA was fairly uniform within a tumor. While MVA was slightly higher in primary tumors than corresponding metastatic sites, the difference was not statistically significant (P = 0.1). MVA in paired primary and metastatic samples correlated moderately well (R = 0.36). MVA was higher in clear cell than papillary histology and oncocytomas (P < 0.0001 and P = 0.018, respectively). CONCLUSIONS: Lack of significant differences MVA in matched primary and metastatic samples suggests that both types of tumors should respond to anti-angiogenic drugs. This should be confirmed on additional cohorts. Given the small cohort, future predictive biomarker studies entailing MVA measurements should include specimens from both sites. Clear cell carcinomas are more vascular than other histologic subtypes, which may explain the higher response rates to anti-angiogenic therapies in clear cell tumors.

Quantitative assessment of invasive mena isoforms (Menacalc) as an independent prognostic marker in breast cancer.

INTRODUCTION: Mena, an Ena/VASP protein family member, is a key actin regulatory protein. Mena is up-regulated in breast cancers and promotes invasion and motility of tumor cells. Mena has multiple splice variants, including Mena invasive (MenaINV) and Mena11a, which are expressed in invasive or non-invasive tumor cells, respectively. We developed a multiplex quantitative immunofluorescence (MQIF) approach to assess the fraction of Mena lacking 11a sequence as a method to infer the presence of invasive tumor cells represented as total Mena minus Mena11a (called Menacalc) and determined its association with metastasis in breast cancer. METHODS: The MQIF method was applied to two independent primary breast cancer cohorts (Cohort 1 with 501 and Cohort 2 with 296 patients) using antibodies against Mena and its isoform, Mena11a. Menacalc was determined for each patient and assessed for association with risk of disease-specific death. RESULTS: Total Mena or Mena11a isoform expression failed to show any statistically significant association with outcome in either cohort. However, assessment of Menacalc showed that relatively high levels of this biomarker is associated with poor outcome in two independent breast cancer cohorts (log rank P = 0.0004 for Cohort 1 and 0.0321 for Cohort 2). Multivariate analysis on combined cohorts revealed that high Menacalc is associated with poor outcome, independent of age, node status, receptor status and tumor size. CONCLUSIONS: High Menacalc levels identify a subgroup of breast cancer patients with poor disease-specific survival, suggesting that Menacalc may serve as a biomarker for metastasis.

CD70 expression patterns in renal cell carcinoma.

CD70 is up-regulated in several malignancies, where it induces cytotoxic effects on B and T lymphocytes, leading to immune escape. Novel therapeutic agents targeting CD70 have entered clinical trials. We characterized expression of CD70 protein in renal cell carcinoma specimens of various histologic subtypes and assessed their prognostic value and association with clinical/pathologic variables. We used tissue microarrays containing 330 cases using a novel fluorescent immunohistochemistry-based method of Automated Quantitative Analysis of in situ protein expression. The mean expression of CD70 was almost twice as high in tumors relative to normal tissue (P < .0001). When broken into subsets, CD70 was higher in sarcomatoid and clear cell tumors (P < .0001) and was variably elevated in oncocytomas and some papillary tumors. No association was found between CD70 expression and stage or grade. High CD70 expression was associated with decreased survival on univariate analysis in the clear cell subset of renal cell carcinoma; however, it did not retain significance on multivariate analysis. Given the elevated expression of CD70 in clear cell, sarcomatoid, and some papillary tumors, our findings suggest that CD70 might be a good drug target in renal cell carcinoma. Additional studies are warranted to assess the association between expression of CD70 and response to therapy with CD70-targeting drugs in renal cell carcinoma.

Punctate LC3B expression is a common feature of solid tumors and associated with proliferation, metastasis, and poor outcome.

PURPOSE: Measurement of autophagy in cancer and correlation with histopathologic grading or clinical outcomes has been limited. Accordingly, we investigated LC3B as an autophagosome marker by analyzing nearly 1,400 tumors from 20 types of cancer, focusing on correlations with clinical outcomes in melanoma and breast cancer. EXPERIMENTAL DESIGN: Staining protocols were developed for automated quantitative analysis (AQUA) using antibodies versus LC3 isoform B (LC3B) and Ki-67. Clinically annotated breast and melanoma tissue microarrays (TMA) and a multitumor array were used. An AQUA program was developed to quantitate LC3B distribution in punctate and diffuse compartments of the cell. RESULTS: LC3B staining was moderate to high in the large majority of tumors. The percentage of area occupied by punctate LC3B was elevated by 3- to 5-fold at high LC3B intensities. In breast cancer and melanoma TMAs, LC3B and Ki-67 showed strong correlations (P < 0.0001), and in multitumor TMAs, mitotic figures were most often seen in tumors with the highest LC3B expression (P < 0.002). In breast cancer, LC3B expression was elevated in node-positive versus node-negative primaries and associated with increased nuclear grade and shortened survival. In a melanoma TMA with no survival data, LC3B levels were highest in nodal, visceral, and cutaneous metastases. CONCLUSIONS: The results reveal a common expression of LC3B in malignancy and support emerging evidence that autophagy plays a significant role in cancer progression. High LC3B was associated proliferation, invasion and metastasis, high nuclear grade, and worse outcome. Thus, autophagy presents a key target of therapeutic vulnerability in solid tumors.

Evaluation of prognostic and predictive value of microtubule associated protein tau in two independent cohorts.

INTRODUCTION: Microtubule associated proteins (MAPs) endogenously regulate microtubule stabilization and have been reported as prognostic and predictive markers for taxane response. The microtubule stabilizer, MAP-tau, has shown conflicting results. We quantitatively assessed MAP-tau expression in two independent breast cancer cohorts to determine prognostic and predictive value of this biomarker. METHODS: MAP-tau expression was evaluated in the retrospective Yale University breast cancer cohort (n = 651) using tissue microarrays and also in the TAX 307 cohort, a clinical trial randomized for TAC versus FAC chemotherapy (n = 140), using conventional whole tissue sections. Expression was measured using the AQUA method for quantitative immunofluorescence. Scores were correlated with clinicopathologic variables, survival, and response to therapy. RESULTS: Assessment of the Yale cohort using Cox univariate analysis indicated an improved overall survival (OS) in tumors with a positive correlation between high MAP-tau expression and overall survival (OS) (HR = 0.691, 95% CI = 0.489-0.974; P = 0.004). Kaplan Meier analysis showed 10-year survival for 65% of patients with high MAP-tau expression compared to 52% with low expression (P = .006). In TAX 307, high expression was associated with significantly longer median time to tumor progression (TTP) regardless of treatment arm (33.0 versus 23.4 months, P = 0.010) with mean TTP of 31.2 months. Response rates did not differ by MAP-tau expression (P = 0.518) or by treatment arm (P = 0.584). CONCLUSIONS: Quantitative measurement of MAP-tau expression has prognostic value in both cohorts, with high expression associated with longer TTP and OS. Differences by treatment arm or response rate in low versus high MAP-tau groups were not observed, indicating that MAP-tau is not associated with response to taxanes and is not a useful predictive marker for taxane-based chemotherapy.

Lymph node ratio should be considered for incorporation into staging for breast cancer.

BACKGROUND: We sought to determine whether lymph node ratio (LNR; defined as number of positive nodes/number of nodes dissected) provides additional prognostic information in node-positive breast cancer patients. METHODS: Data from a cohort of 319 node-positive breast cancer patients diagnosed between 1956 and 1982 were analyzed for overall survival (OS) on the basis of current American Joint Committee on Cancer (AJCC) nodal staging versus LNR. RESULTS: In terms of AJCC categorization, 157 patients (49.2%) were pN1 (1-3 positive nodes), 97 (30.4%) were pN2 (4-9 positive nodes), and 65 (20.4%) were pN3 (≥10 positive nodes). In terms of LNR, 90 (28.2%) were low risk (LNR = 0.01-0.20), 119 (38.3%) were intermediate risk (LNR = 0.21-0.65), and 110 (34.5%) were high risk (LNR > 0.65). The median follow-up was 68.7 months. AJCC nodal status correlated with OS (median OS 85.9, 70.4, and 48.4 months for pN1-3, respectively, P = 0.018). LNR also correlated with OS (median OS 105.8, 72.2, and 48.4 months for the low-, intermediate-, and high-risk groups, respectively, P < 0.005). On multivariate analysis, LNR predicted OS independent of pN status (P < 0.001). Stratifying by pN status, LNR could discriminate distinct subpopulations of patients with significantly different OS rates. In a multivariate model controlling for clinicopathologic factors (tumor size, grade, estrogen receptor, progesterone receptor, and her-2-neu status), LNR remained a significant predictor of OS (P < 0.001). CONCLUSIONS: LNR has the ability to discriminate populations with different OS rates within traditional AJCC node classification groups and predicts OS independent of traditional clinicopathologic factors. These results should be validated and considered for future incorporation into the breast cancer staging system.

Quantitative assessment shows loss of antigenic epitopes as a function of pre-analytic variables.

Pre-analytic variables, specifically cold ischemic time, have been implicated as key variables in the measurement of proteins by immunohistochemistry. To determine the significance and magnitude of antigenic loss due to pre-analytic variables, we have compared protein antigenicity in core needle biopsies, with essentially no cold ischemic time, with that in routinely processed tumor resection specimens. Two cohorts of matched core needle biopsies and tumor resections were collected with 20 matched pairs and 14 matched pairs, respectively. Both series were analyzed by quantitative immunofluorescence using the AQUA® method. Epitopes phospho-ERK, total ERK, phospho-AKT, total AKT, phospho-S6K1, total S6K1, estrogen receptor (ER), Ki67, cytokeratin and GAPDH were assessed. Detection levels for all phospho-epitopes were significantly decreased in tumor resections compared with biopsies while no significant change was seen in the corresponding total proteins. Of the other four proteins examined, ER and cytokeratin showed significant loss of antigenicity. This data suggest that measurement of phospho-protein antigenicity in formalin-fixed tissue by immunological methods is dramatically affected by pre-analytic variables. This study suggests that core needle biopsies are more accurate for assessment of tissue biomarkers.

Vertical targeting of the phosphatidylinositol-3 kinase pathway as a strategy for treating melanoma.

PURPOSE: Melanoma is relatively resistant to chemotherapy; improved targeting of molecules critical for cell proliferation and survival are needed. Phosphatidylinositol-3 kinase (PI3K) is an important target in melanoma; however, activity of PI3K inhibitors (PI3KI) is limited. Our purpose was to assess mTOR as a cotarget for PI3K. METHODS: Using a method of quantitative immunofluorescence to measure mTOR expression in a large melanoma cohort, we studied associations with PI3K subunits, p85 and p110α. We assessed addition of the mTOR inhibitor rapamycin to 2 PI3KIs, NVP-BKM120 and LY294002. We studied in vitro activity of a novel dual PI3K/mTOR inhibitor NVP-BEZ235 and activity of the combination of NVP-BEZ235 and the MAP/ERK kinase (MEK) inhibitor AZD6244. RESULTS: Strong coexpression of mTOR and p110α was observed (ρ = 0.658; P < 0.0001). Less coexpression was seen with p85 (ρ = 0.239; P < 0.0001). Strong synergism was shown between rapamycin and both PI3KIs. Activity of both PI3KIs was similarly enhanced with all rapamycin concentrations used. The dual PI3K/mTOR inhibitor effectively inhibited viability in 23 melanoma cell lines (IC(50) values in the nanomolar range), regardless of B-Raf mutation status, with resultant reduction in clonogenicity and downregulation of pAkt and pP70S6K. Synergism was seen when combining NVP-BEZ235 and AZD6244, with resultant increases in poly(ADP-ribose) polymerase and caspase-2 cleavage. CONCLUSIONS: mTOR and p110α are coexpressed in melanoma. Rapamycin concentrations as low as 1 nmol/L enhance activity of PI3KIs. The dual PI3K/mTOR inhibitor NVP-BEZ235 is highly active in melanoma cells in vitro, suggesting that concurrent PI3K and mTOR targeting in melanoma warrants further investigation, both alone and in combination with MEK inhibitors.

Benefits of biomarker selection and clinico-pathological covariate inclusion in breast cancer prognostic models.

INTRODUCTION: Multi-marker molecular assays have impacted management of early stage breast cancer, facilitating adjuvant chemotherapy decisions. We generated prognostic models that incorporate protein-based molecular markers and clinico-pathological variables to improve survival prediction. METHODS: We used a quantitative immunofluorescence method to study protein expression of 14 markers included in the Oncotype DX™ assay on a 638 breast cancer patient cohort with 15-year follow-up. We performed cross-validation analyses to assess performance of multivariate Cox models consisting of these markers and standard clinico-pathological covariates, using an average time-dependent Area Under the Receiver Operating Characteristic curve and compared it to nested Cox models obtained by robust backward selection procedures. RESULTS: A prognostic index derived from a multivariate Cox regression model incorporating molecular and clinico-pathological covariates (nodal status, tumor size, nuclear grade, and age) is superior to models based on molecular studies alone or clinico-pathological covariates alone. Performance of this composite model can be further improved using feature selection techniques to prune variables. When stratifying patients by Nottingham Prognostic Index (NPI), most prognostic markers in high and low NPI groups differed. Similarly, for the node-negative, hormone receptor-positive sub-population, we derived a compact model with three clinico-pathological variables and two protein markers that was superior to the full model. CONCLUSIONS: Prognostic models that include both molecular and clinico-pathological covariates can be more accurate than models based on either set of features alone. Furthermore, feature selection can decrease the number of molecular variables needed to predict outcome, potentially resulting in less expensive assays.

Automated analysis of tissue microarrays.

The analysis of protein expression in tissue by immunohistochemistry (IHC) presents three significant challenges. They are (1) the time-consuming nature of pathologist-based scoring of slides; (2) the need for objective quantification and localization of protein expression; and (3) the need for a highly reproducible measurement to limit intra- and inter-observer variability. While there are a variety of commercially available platforms for automated chromagen-based and fluorescence-based image acquisition of tissue microarrays, this chapter is focused on the analysis of fluorescent images by AQUA(R) analysis (Automated QUantitative Analysis) and the solutions offered by such a method for research and diagnostics. AQUA analysis is a method for molecularly defining regions of interest or "compartments" within a tissue section. The methodology can be utilized with tissue microarrays to provide rapid, quantitative, localized, and reproducible protein expression data that can then be used to identify statistically relevant correlations in populations. Ultimately this allows for a multiplexed, objective and standardized quantitative approach for biomarker research and diagnostic assay development for protein expression in tissue.

In situ identification of putative cancer stem cells by multiplexing ALDH1, CD44, and cytokeratin identifies breast cancer patients with poor prognosis.

A subset of cells, tentatively called cancer stem cells (CSCs), in breast cancer have been associated with tumor initiation, drug resistance, and tumor persistence or aggressiveness. They are characterized by CD44 positivity, CD24 negativity, and/or ALDH1 positivity in flow cytometric studies. We hypothesized that the frequency or density of these cells may be associated with more aggressive tumor behavior. We borrowed these multiplexed, flow-based methods to develop an in situ method to define CSCs in formalin-fixed paraffin-embedded breast cancer tissue, with the goal of assessing the prognostic value of the presence of CSCs in breast cancer. Using a retrospective collection of 321 node-negative and 318 node-positive patients with a mean follow-up time of 12.6 years, we assessed TMAs using the AQUA method for quantitative immunofluorescence. Using a multiplexed assay for ALDH1, CD44, and cytokeratin to measure the coexpression of these proteins, putative CSCs appear in variable sized clusters and in 27 cases (of 490), which showed significantly worse outcome (log rank P = 0.0003). Multivariate analysis showed that this marker combination is independent of tumor size, histological grade, nodal status, ER-, PR,- and HER2-status. In this cohort, ALDH1 expression alone does not significantly predict outcome. We conclude that the multiplexed method of in situ identification of putative CSCs identifies high risk patients in breast cancer.

Quantitative expression of VEGF, VEGF-R1, VEGF-R2, and VEGF-R3 in melanoma tissue microarrays.

Angiogenesis is required for progression and metastasis of melanoma. Analysis of angiogenic molecules in benign and malignant tissues may allow identification of markers useful for prediction of sensitivity to antiangiogenic agents. We hypothesized that differential expression of vascular endothelial growth factor (VEGF) and its receptors VEGF-R1, VEGF-R2, and VEGF-R3 would be higher in melanomas than nevi and higher in advanced melanoma. Using automated quantitative analysis, we quantified VEGF, -R1, -R2 and -R3 expression in melanoma tissue microarrays composed of 540 nevi and 468 melanoma specimens (198 primaries, 270 metastases). VEGF, VEGF-R1, VEGF-R2, and VEGF-R3 expression was significantly higher in melanomas than nevi by unpaired t tests (P < .0001). VEGF-R2 expression was higher in metastatic specimens (P < .0001), but VEGF-R3 expression was higher in primaries (P < .0001). VEGF was coexpressed with all 3 receptors when assessed by Spearman's rank correlation. VEGF, VEGF-R1, VEGF-R2, and VEGF-R3 expression is higher in melanomas than nevi. Higher expression of VEGF-R2 was found in metastases versus primaries, supporting the idea that selection for an angiogenic phenotype in metastatic melanoma is conferred via up-regulation of VEGF-R2. However, higher expression of VEGF-R3 was seen on primary lesions, potentially implicating this receptor in initiation of lymphatic tumor spread. Clinical trials using antiangiogenic agents in melanoma should include correlative assays of VEGF, VEGF-R1, VEGF-R2, and VEGF-R3 as biomarkers of response to therapy, preferably using quantitative methods such as automated quantitative analysis. Such assessments could assist with evaluation of these molecules as therapeutic targets in melanoma, ultimately facilitating improved selection of patients for treatment.

Melanoma prognostic model using tissue microarrays and genetic algorithms.

PURPOSE: As a result of the questionable risk-to-benefit ratio of adjuvant therapies, stage II melanoma is currently managed by observation because available clinicopathologic parameters cannot identify the 20% to 60% of such patients likely to develop metastatic disease. Here, we propose a multimarker molecular prognostic assay that can help triage patients at increased risk of recurrence. METHODS: Protein expression for 38 candidates relevant to melanoma oncogenesis was evaluated using the automated quantitative analysis (AQUA) method for immunofluorescence-based immunohistochemistry in formalin-fixed, paraffin-embedded specimens from a cohort of 192 primary melanomas collected during 1959 to 1994. The prognostic assay was built using a genetic algorithm and validated on an independent cohort of 246 serial primary melanomas collected from 1997 to 2004. RESULTS: Multiple iterations of the genetic algorithm yielded a consistent five-marker solution. A favorable prognosis was predicted by ATF2 ln(non-nuclear/nuclear AQUA score ratio) of more than -0.052, p21(WAF1) nuclear compartment AQUA score of more than 12.98, p16(INK4A) ln(non-nuclear/nuclear AQUA score ratio) of < or = -0.083, beta-catenin total AQUA score of more than 38.68, and fibronectin total AQUA score of < or = 57.93. Primary tumors that met at least four of these five conditions were considered a low-risk group, and those that met three or fewer conditions formed a high-risk group (log-rank P < .0001). Multivariable proportional hazards analysis adjusting for clinicopathologic parameters shows that the high-risk group has significantly reduced survival on both the discovery (hazard ratio = 2.84; 95% CI, 1.46 to 5.49; P = .002) and validation (hazard ratio = 2.72; 95% CI, 1.12 to 6.58; P = .027) cohorts. CONCLUSION: This multimarker prognostic assay, an independent determinant of melanoma survival, might be beneficial in improving the selection of stage II patients for adjuvant therapy.