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Parker, Alexander S.

https://orcid.org/0000-0001-6820-274X

Mayo Clinic

Mayo Clinic in Florida

Citations 60

Loss of BAP1 and PBRM1 protein expression and its association with clear cell renal cell carcinoma-specific survival.
Serie, Daniel, Eckel‐Passow, Jeanette E. , Parker, Alexander S. , Joseph, Richard W. , Kapur, Payal , Ho, Thai H. , Brugarolas, James

Journal of Clinical Oncology | February 24, 2017 | Volume: 32 | Issue: 4_suppl | Pages: 414-414

10.1200/jco.2014.32.4_suppl.414 Get It

414 Background: While mutations in PBRM1 (~40%) and BAP1(~10%) are associated with clinical outcomes and pathologic features in clear cell renal cell carcinoma (ccRCC), the impact of protein expression of these genes remains unknown. Herein, we quantify PBRM1/BAP1 protein expression in a large cohort of patients with localized ccRCC and associate expression with cancer-specific survival (CSS) and pathologic features. Methods: We utilized the Mayo Clinic Renal Registry and identified 1,416 patients who underwent nephrectomy to treat clinically localized ccRCC between 1/3/1990 and 4/14/2009. We used immunohistochemistry (IHC) to detect PBRM1/BAP1 expression, and a central pathologist blinded to the outcomes scored tumors as either positive or negative. Tumors with heterogeneous or equivocal staining were excluded from this analysis. We generated Cox proportional hazard regression models for associations with ccRCC-SS, and we employed Mann-Whitney U tests for associations with pathologic features. Results: Of the 1,416 samples, 1,232 (87%) were PBRM1/BAP1 positive or negative, 163 (11%) had heterogeneous staining, and 21 (1%) could not be assessed. The distribution and association of PBRM1/BAP1 phenotypes with clinical outcomes are listed in the table below. PBRM1+/BAP1+ tumors have the best CSS, and PBRM1-/BAP1- have the worst. In addition, PBRM1/BAP1 expression strongly associated with the tumor size, stage, grade, and tumor necrosis (p<0.0001). Conclusions: This study is the first and largest to quantify PRBM1/BAP1 protein expression in ccRCC tumors. We were able to quantify PBRM1/BAP1 through IHC in the vast majority of tumors (87%), and PRBM1/BAP1 expression strongly associates with both CSS and pathologic tumor characteristics. Our data confirms our previous findings of the importance of PRBM1/BAP1 in the molecular pathogenesis of ccRCC. [Table: see text]
Association of topoisomerase II expression and cancer-specific death in patients with surgically resected clear cell renal cell carcinoma.
Gardner, F., Serie, Daniel, Hilton, Tracy, Parasramka, Mansi, Eckel‐Passow, Jeanette E. , Cheville, John C. , Leibovich, Bradley C. , Parker, Alexander S. , Joseph, Richard W.

Journal of Clinical Oncology | February 24, 2017 | Volume: 31 | Issue: 6_suppl | Pages: 446-446

10.1200/jco.2013.31.6_suppl.446 Get It

446 Background: Despite the development of prognostic algorithms based on clinico-pathologic features, the ability to identify aggressive forms of clear cell renal cell carcinoma (ccRCC) remains suboptimal. Topoisomerase IIA (TOP2a) is a biomarker of DNA replication and a target for antineoplastic agents. Herein, we evaluate the association of TOP2a expression in ccRCC tumors with pathologic features of aggressiveness and risk of cancer-specific death. Methods: We identified 947 patients who underwent nephrectomy to treat clinically localized ccRCC between January 16, 1990, and September 27, 2006. TOP2a expression was assessed using IHC and scored as number of positive cells per mm2. We evaluated TOP2a expression using a continuous variable and tertile categories. For associations with pathologic features, we employed Kruskal-Wallis tests and for associations with cancer-specific survival, we generated Cox proportional hazard regression models. Results: HigherTOP2a expression is associated with later stage, higher grade and higher Mayo SSIGN score (all p < 0.001). The risk of death from RCC increases with increasing TOP2a expression (p trend < 0.0001). Compared to patients in the lowest tertile, those patients with tumors in the highest tertile of TOP2a expression were at increased risk of RCC death (HR=2.31 95% CI 1.64-3.25; p < 0.0001). Interestingly, among those patients with low risk disease (SSIGN score 0-3; ~95% 10 year survival), those with high TOP2a were at increased risk of RCC death (HR=3.09 95% CI 1.29-7.40; p = 0.01). Conclusions: Higher TOP2a expression is associated with more aggressive pathologic features and increased risk of cancer-specific death among patients undergoing surgery for localized ccRCC. If confirmed, these data support further inquiry for TOP2a as a prognostic and predictive biomarker for ccRCC patients.
Delay to colectomy and survival for patients diagnosed with colon cancer.
Diehl, Nancy N. , Parker, Alexander S. , Wasif, Nabil , Bagaria, Sanjay P. , Heckman, Michael G.

Journal of Clinical Oncology | February 24, 2017 | Volume: 33 | Issue: 3_suppl | Pages: 541-541

10.1200/jco.2015.33.3_suppl.541 Get It

541 Background: A long wait-time for colectomy for colon cancer should theoretically affect survival but, to date, the association between delay to colectomy and survival remains unresolved. Methods: We studied 4,692 patients who underwent colectomy for colon cancer between 1990 and 2012. Wait-time was defined as the number of days between diagnosis and colectomy. Cox regression models were used to estimate all-cause mortality across wait-time categories. Multivariable analyses were controlled for clinicopathologic variables and Charlson comorbidity index. Results: The number of patients in the wait-time group of 1-28 days was 3,950 (84.2%), 29-84 days was 681 (22.7%), and >84 days was 61 (1.3%). A wait-time of 29-84 days was not associated with an increased risk of death (HR=1.13; p=0.056) when compared to a wait-time of 1-28 days. Though a wait-time >84 days represented a small group, it was associated with an increased risk of death (HR=1.60; p=0.013). For patients with stage I and II disease, wait-times of 29-84 days (HR =1.44; p=0.0001) and >84 days (adjusted HR=2.24; p=0.0007) were associated with an increased risk of mortality. Conclusions: A wait-time for colon cancer surgery of up to 12 weeks is likely safe for most patients. However, those suspected to have early-stage colon cancer may benefit from less of delay. These data provide a framework to address concerns over prolonged wait-times and can direct efforts for timely surgical intervention in patients with colon cancer. [Table: see text]
High concordance of BAP1 and PBRM1 expression in patient-matched primary and metastatic ccRCC tumors.
Shreders, Amanda , Serie, Daniel, Eckel‐Passow, Jeanette E. , Parker, Alexander S. , Joseph, Richard W. , Kapur, Payal , Ho, Thai H. , Brugarolas, James

Journal of Clinical Oncology | February 24, 2017 | Volume: 33 | Issue: 7_suppl | Pages: 507-507

10.1200/jco.2015.33.7_suppl.507 Get It

507 Background: Clear cell renal cell carcinoma (ccRCC) is a well-described molecularly heterogeneous tumor. Herein, we assessed the concordance of two of the most commonly mutated genes in ccRCC, PBRM1 (~50%), and BAP1 (~15%), in patient-matched primary and metastatic tumors. Methods: One pathologist (PK) assessed PBRM1 and BAP1 protein expression using immunohistochemistry (IHC) in 99 patients with a primary and at least one metastatic ccRCC tumor available for analysis. All available metastatic tumors were analyzed. Results: A total of 99 patients (48 M0 and 51 M1) had both a primary tumor and at least one metastatic tumor available for analysis. There were a total of 158 metastases with one patient having up to 7 metastases available for analysis. The concordance between primary and patient-matched metastasis was 87% for PBRM1 and 99% for BAP1. We observed a similar concordance between patients with M0 versus M1 disease. Conclusions: While ccRCC is molecularly heterogeneous, PRBM1, and BAP1 are largely concordant between primary and metastatic lesions suggesting that PBRM1 and BAP1 are genetically truncal events in the molecular pathogenesis of ccRCC.
Association and prognostic impact of peripheral blood counts with tumor programmed death ligand one expression.
Serie, Daniel, Eckel‐Passow, Jeanette E. , Cheville, John C. , Kwon, Eugene D., Thompson, R. Houston, Leibovich, Bradley C. , Parker, Alexander S. , Lewis, Daniel , Joseph, Richard W. , Ho, Thai H.

Journal of Clinical Oncology | February 24, 2017 | Volume: 33 | Issue: 7_suppl | Pages: 447-447

10.1200/jco.2015.33.7_suppl.447 Get It

447 Background: Components of the peripheral blood counts (PBC) are associated with poor prognosis in patients diagnosed with non-metastatic clear cell renal cell carcinoma (ccRCC). Related to this, higher tumor expression of programmed death ligand one (PDL1) is also associated with poor ccRCC prognosis. Herein, we utilize a large cohort of patients undergoing nephrectomy for localized ccRCC to evaluate the association of PBC with tumor expression of PDL1. Secondarily, we examine the association of PBC and relapse free survival (RFS) after adjusting for age and PDL1 expression. Methods: Through chart review, we obtained PBC values at time of nephrectomy for patients enrolled in the Mayo Clinic Renal Registry from 1990-2009 who were treated for localized (M0) ccRCC including the following: hemoglobin (HGB), white blood cell (WBC), absolute neutrophil count (ANC), absolute lymphocyte count (ALC), absolute eosinophil count (AEC), absolute monocyte count (AMC), and platelets (PLT). We determined tumor PDL1 expression as a continuous variable (% of positive PDL1 tumor cells) using the 5H1 antibody on archived tissues. We analyzed the correlation of PBC values with PDL1 expression as a continuous variable using a linear estimate. To evaluate the association of PBC values with RFS after adjusting for PDL1 expression, we employed multivariate Cox regression models. Results: A total of 706 ccRCC patients had available PDL1 expression and PBC. PDL1 expression was inversely associated with HGB (linear estimate of -0.02, p<0.001) and positively associated with platelets (linear estimate 1.73, p<0.001) whereas there was no association with PDL1 with WBC, ANC, AEC, or AMC. After adjusting for age and PDL1 expression, a higher HGB (HR=0.87, p<0.001), higher ALC (HR 0.68, p=0.003), and higher AEC (HR 0.12, p=0.002) were all associated with improved relapse free survival. Conversely, higher PLT was associated with decreased RFS (HR 1.002, p<0.001). Conclusions: PDL1 expression is associated with decreased HGB and increased PLT at the time of nephrectomy. After adjusting for PDL1 expression and age, higher HGB, ALC, and AEC are associated with improved RFS, while higher platelets are associated with decreased RFS.
Abstract 10: Concordance of BAP1, PBRM1, Ki-67, and TOPOIIa protein expression in primary clear cell renal cell carcinoma tumors and patient-matched metastatic tumors
Eckel‐Passow, Jeanette E. , Serie, Daniel, Cheville, John C. , Harrington, Sue M., Hilton, Tracy, Lohse, Christine M. , Shreders, Amanda , Thompson, R. Houston, Leibovich, Bradley C. , Kwon, Eugene D., Parker, Alexander S. , Ho, Thai H. , Kapur, Payal , Brugarolas, James , Joseph, Richard W.

Clinical Cancer Research | May 20, 2016 | Volume: 22 | Issue: 1_Supplement | Pages: 10-10

10.1158/1557-3265.pmsclingen15-10 Get It

Abstract Introduction: Efforts to improve clear cell renal cell carcinoma (ccRCC) mortality have focused primarily on evaluating prognostic biomarkers in primary tumors in order to identify indicators of response to treatment and targets for novel therapies. To date little attention has been paid to the status of these biomarkers in the more therapeutically-relevant metastatic tumor. Thus, we evaluated concordance of expression of four key prognostic ccRCC biomarkers (BAP1, PBRM1, Ki-67 and TOPOIIa) in a large cohort of patient-matched primary ccRCC and metastatic tumors. Methods: We identified 114 patients treated surgically for ccRCC between 1990 and 2005 who had synchronous (M1) or metachronous (M0) metastases, underwent metastasectomy for at least one metastatic lesion and had archived tissue available from the primary and at least one metastatic tumor. We performed IHC on all primary and metastatic tumors for BAP1, PBRM1, Ki-67, and TOPOIIa using previously-published protocols. BAP1 and PBRM1 expression was categorized as positive or negative and Ki-67 and TOPOIIa was quantified as the number of positive cells per mm2. For BAP1 and PBRM1, we calculated the concordance between patient-matched primary and metastatic tumors as the percentage of pairs where the primary and metastatic tumor had the same designation (i.e., positive or negative). For TOPOIIa and Ki-67, we assessed concordance using Spearman correlation coefficient. Analysis of variance was used to evaluate if concordance between primary-metastatic tumor pairs for TOPOIIa and Ki-67 was associated with metastatic site, metastatic timing (M0/M1), metastatic tumor grade, metastatic tumor necrosis, and metastatic tumor sarcomatoid differentiation. Results: There were a total of 161 patient-matched metastatic tumors available for the 114 patients: 78 patients had only a single metastasis while 36 patients had two or more metastases. While sites of metastases varied, pulmonary metastases were the most common (44% of all metastases). Loss of BAP1 expression was observed in19% of the primary ccRCC and 98.6% of the tumor pairs had concordant BAP1 status between the paired primary and metastatic tumors. Loss of PBRM1 was observed in 56% of the primary ccRCC tumors and 89.3% of tumor pairs showed concordant PBRM1 status. By comparison, median expression of Ki-67 was 65.0mm2 in the primary ccRCC tumors and the Pearson correlation with the patient-matched metastatic tumors was 0.43. The difference in Ki-67 expression between primary-metastatic tumor pairs was associated with necrosis in the metastatic tumor (p=0.014). Median expression of TOPOIIa was 2.6mm2 in the primary ccRCC tumors and the Pearson correlation with the patient-matched metastatic tumors was 0.25. The difference in TOPOIIa expression between primary-metastatic tumor pairs was associated with metastatic site (p=0.0006) and metastases to the heart were significantly different than pulmonary metastases (p&lt;0.0001). Additionally, synchronous metastases had larger differences from their patient-matched primary tumors in comparison to metachronous metastases (p=0.012), as did necrotic metastases (p=0.028). Conclusion: We observed high concordance for loss of BAP1 and PBRM1 expression between primary ccRCC and metastatic tumors in the same patient. Conversely, we noted high discordance in protein expression of Ki-67 and TOPOIIa between patient-matched primary-metastatic tumor pairs. Moreover, this discordance varied by key pathological features. Our results suggest that using the status of a biomarker in primary ccRCC as a guide for the status in metastatic tumors is not always appropriate and needs to be evaluated on a marker-by-marker basis. Citation Format: Jeanette E. Eckel-Passow, Daniel J. Serie, John C. Cheville, Thai H. Ho, Sue M. Harrington, Tracy Hilton, Christine Lohse, Amanda Shreders, Payal Kapur, James Brugarolas, R Houston Thompson, Bradley C. Leibovich, Eugene D. Kwon, Richard W. Joseph, Alexander S. Parker. Concordance of BAP1, PBRM1, Ki-67, and TOPOIIa protein expression in primary clear cell renal cell carcinoma tumors and patient-matched metastatic tumors. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Integrating Clinical Genomics and Cancer Therapy; Jun 13-16, 2015; Salt Lake City, UT. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(1_Suppl):Abstract nr 10.
Clear Cell Renal Cell Carcinoma Subtypes Identified by BAP1 and PBRM1 Expression
Joseph, Richard W. , Serie, Daniel, Parasramka, Mansi, Ho, Thai H. , Cheville, John C. , Frenkel, Eugene P., Parker, Alexander S. , Brugarolas, James , Kapur, Payal , Serie, Daniel J, Frenkel, Eugene, Ho, Thai , Brugarolas, James

Journal of Urology | August 20, 2015 | Volume: 195 | Issue: 1 | Pages: 180-187

10.1016/j.juro.2015.07.113 Get It

Abstract 3899: Integrating RNA/DNA analysis with a comprehensive cancer panel to improve interpretations of stage four metastatic renal cell carcinoma
Boyle, Sean M. , Clark, Michael , Helman, Elena , Parker, Alexander S. , Luo, Shujun , Kirk, Scott, Sripakdeevong, Parin, Karbelashvili, Mirian, Church, Deanna M. , West, John, Chen, Rich, Ho, Thai H. , Snyder, Michael

Cancer Research | August 5, 2015 | Volume: 75 | Issue: 15_Supplement | Pages: 3899-3899

10.1158/1538-7445.am2015-3899 Get It

Abstract Next-generation sequencing is now commonly applied to measure genomic modifications, providing the opportunity for a more accurate view of cancer progression. That being said, several challenges including tumor purity, heterogeneity and the broad set of cancer associated cellular functions, increase the difficulty of interpreting cancer genomes and make analyzing them distinct from analysis of germline diseases. The ability to detect low allelic mutations in the broad set of cancer-associated genes is critically important. To address these issues, we developed an extended cancer panel, a targeted enrichment sequencing platform that includes over 1,300 cancer genes and 200 miRNAs that improves coverage in traditionally difficult to sequence NGS regions. In this study, we apply an integrated RNA/DNA analysis approach as well as our extended cancer panel to explore mutations in metastatic renal cell carcinoma (RCC) tissue samples before and after treatment. Our goal with this study was to test the importance of integrating DNA and RNA analysis, which allows for detection of mutational events that cannot be observed by either method alone. With RNA analysis it is possible to detect gene fusion events, expression of small variants (SNVs/indels), and gene expression levels while DNA analysis allows for detection of loss of heterozygosity (LOH), copy number variants (CNVs), and small variants. By integrating both the RNA and DNA analysis, it is possible to identify unique variant classes, such as unexpressed variants, allele specific expression (ASE), effects of CNVs on gene expression levels, and how fusion gene integration sites affect CNVs. In our study, each variant class was interpreted pre- and post-treatment, allowing for optimal analysis of treatment effectiveness. By applying both our RNA/DNA integration approach and our extended cancer panel to investigate metastatic RCC samples, we were able to classify many genomic alterations that drive cancer progression. For example, we found that anywhere from 5% to 30% of small variant mutations in driver genes called in the DNA reside in genes that are unexpressed in the RNA. Likewise, we noted multiple cases of ASE, where high profile variants observed in DNA were entirely absent in the RNA despite high expression levels. Strong correlations between CNVs observed in DNA and gene expression changes found in RNA were also detected. We also observed that about half of the RCC samples we tested were biallelic for VHL mutations, suggesting inherited predisposition combined with second hit somatic mutations, facilitating cancer progression. This analysis demonstrates how combining an integrated RNA/DNA approach with a cancer focused augmented enrichment panel allows for detection of both low allelic representation variants and unique variant classes, both of which are critical for accurate interpretation of cancer samples. Citation Format: Sean M. Boyle, Michael J. Clark, Elena Helman, Alexander S. Parker, Thai Ho, Shujun Luo, Scott Kirk, Parin Sripakdeevong, Mirian Karbelashvili, Deanna M. Church, Michael Snyder, John West, Rich Chen. Integrating RNA/DNA analysis with a comprehensive cancer panel to improve interpretations of stage four metastatic renal cell carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3899. doi:10.1158/1538-7445.AM2015-3899
Abstract B61: Evaluation of the prevalence of hypovitaminosis D and vitamin D awareness in African Americans living in a metropolitan southern community
Parker, Alexander S. , Albertie, Monica, Diehl, Nancy N. , Drake, Matthew T.

Cancer Epidemiology, Biomarkers & Prevention | May 15, 2015 | Volume: 23 | Issue: 11_Supplement | Pages: B61-B61

10.1158/1538-7755.disp13-b61 Get It

Abstract Background: The health benefits associated with maintaining adequate circulating levels of vitamin D are well known. More recently, data have emerged supporting an inverse association between vitamin D levels and risk of several human cancers. Related to this, African Americans (AAs) are at increased risk of hypovitaminosis D due to elevated levels of melanin in the skin that reduce the conversion of cholesterol to vitamin D3 (cholecalciferol). Herein, we simultaneously assess levels of awareness regarding the health benefits of vitamin D and the prevalence of hypovitaminosis D in a metropolitan African American community. Methods: From January 2012 through August 2013, we partnered with African American churches and community organizations in the metropolitan Jacksonville, FL area to provide nine education programs focused on vitamin D and the evidence linking poor vitamin D levels with increased risk of chronic disease, including cancer. Participants were offered free vitamin D testing to estimate the prevalence of vitamin D insufficiency (&lt;25 ng/mL) and deficiency (&lt; 15 ng/mL) in this population. Moreover, participants also completed surveys prior to the events to assess their awareness of issues related to vitamin D, including the emerging link with cancer risk. Results: Out of 305 attendees, 285 agreed to provide blood samples for vitamin D screening. Of these, 262 (92%) self-identified as African American (75% female, 25% male). The median age of the AA participants was 59 years. Laboratory testing for 25(OH) vit D revealed 43% of the AA participants had normal levels of vitamin D (&gt;25 ng/mL), 35% had insufficient levels (15-24 ng/mL) and 22% had deficient levels (&lt; 15 ng/mL). Of interest, despite the high level of hypovitaminosis D (insufficient + deficient) in this population, participants reported high levels of awareness regarding vitamin D prior to the education program. For example, 82% of AA respondents correctly answered that the main source of vitamin D came from sunlight and 76% correctly answered that AAs are at risk of lower levels of vitamin D because of the amount of melanin in the skin. Moreover, 83% of AA respondents answered that maintaining proper vitamin D levels could potentially decrease risk for various chronic health conditions, including certain cancers. Finally, 75% of the AA participants reported never having had a vitamin D test discussed with them by their doctor. Conclusions: We report a high prevalence of hypovitaminosis D in a large AA community in Jacksonville, FL. Moreover, we report that despite this high prevalence, awareness of the health benefits of vitamin D are high, yet regular vitamin D testing levels appear to be very low. These data provide the foundation for developing targeted interventions to raise vitamin D levels in this community. Citation Format: Alexander Parker, Monica Albertie, Nancy Diehl, Matthew Drake. Evaluation of the prevalence of hypovitaminosis D and vitamin D awareness in African Americans living in a metropolitan southern community. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr B61. doi:10.1158/1538-7755.DISP13-B61
Whole Exome Sequencing of a Patient with Metastatic Hidradenocarcinoma and Review of the Literature
Gupta, Eva , Guthrie, Kimberly J., Krishna, Murli , Asmann, Yan W. , Parker, Alexander S. , Joseph, Richard W. , Asmann, Yan

Rare Tumors | April 1, 2015 | Volume: 7 | Issue: 1 | Pages: 29-33

10.4081/rt.2015.5719 Get It

Hidradenocarcinoma is a rare malignancy of the sweat glands with only a few cases reported in literature. The management of these tumors is based on the extent of disease with local disease managed with surgical resection. These can tumors carry a high potential of lymphatic and vascular spread and local and distant metastases are not uncommon. Given the rarity of the tumor and lack of genetic and clinical data about these tumors, there is no consensus on the proper management of metastatic disease. Here in we report the first case of metastatic hidradenocarcinoma with detailed molecular profiling including whole exome sequencing. We identified mutations in multiple genes including two that are potentially targetable: PTCH1 and TCF7L1. Further work is necessary to not only confirm the presence of these mutations but also to confirm the clinical significance.