Lee D. Gibbs

MIEN1 promotes oral cancer progression and implicates poor overall survival

Oral squamous cell carcinoma is a highly malignant tumor with the potential to invade local and distant sites and promote lymph node metastasis. Major players underlying the molecular mechanisms behind tumor progression are yet to be fully explored. Migration and invasion enhancer 1 (MIEN1), a novel protein overexpressed in various cancers, facilitates cell migration and invasion. In the present study we investigated the expression and role of MIEN1 in oral cancer progression using an in vitro model, patient derived oral tissues and existing TCGA data. Expression analysis using immortalized normal and cancer cells demonstrated increased expression of MIEN1 in cancer. Assays performed after MIEN1 knockdown in OSC-2 cells showed decreased migration, invasion and filopodia formation; while MIEN1 overexpression in DOK cells increased these characteristics and also up-regulated some Akt/NF-κB effectors, thereby suggesting an important role for MIEN1 in oral cancer progression. Immunohistochemical staining and analyses of oral tissue specimens, collected from patients over multiple visits, revealed significantly more staining in severe dysplasia and squamous cell carcinoma compared to mildly dysplastic or hyperplastic tissues. Finally, this was corroborated with the TCGA dataset, where MIEN1 expression was not only higher in intermediate and high grade cancer with significantly lower survival but also correlated with smoking. In summary, we demonstrate that MIEN1 expression not only positively correlates with oral cancer progression but also seems to be a critical molecular determinant in migration and invasion of oral cancer cells, thereby, playing a possible role in their metastatic dissemination.

Prognostic impact of AnxA1 and AnxA2 gene expression in triple-negative breast cancer

Objective Previous studies have shown Annexin A1 (AnxA1) and Annexin A2 (AnxA2) association with the aggressive behavior of Triple Negative Breast Cancer (TNBC). Our aim was to determine the correlation of AnxA1 and AnxA2 with poor prognosis of TNBC patients. Methods We analyzed the gene expression of the human annexin family from microarray datasets and correlated with clinical outcomes to determine their ability to predict prognosis. Results Within a mean follow-up time of 57.2 months in our TNBC cohort, high AnxA1 expression was an independent indicator of poor overall survival (OS) [hazard ratio (HR), 2.14; 95% confidence interval (CI), 1.22-3.78] and relapse-free survival (RFS) prognosis [HR, 1.66; 95% CI, 1.28-2.17]. Additionally, high AnxA2 expression was an independent indicator of poor OS [HR, 2.66; 95% CI, 1.14-6.25], RFS [HR, 1.45; 95% CI, 1.12-1.89], RFS [HR, 1.45; 95% CI, 1.12-1.89), and distant metastasis free survival (DMFS) prognosis [HR, 1.5; 95% CI, 1.16-1.95]. Analyses of TNBC patients with both high AnxA1 and AnxA2, demonstrates a significant decrease in OS (P=0.0017) and RFS (P=0.0002) when compared to the expression of genes independently. Furthermore, AnxA1 prognostic impact relies on high AnxA2 expression and both are preferential for TNBC when compared to other breast cancer subtypes. Conclusion Together these findings indicate that AnxA1 and AnxA2 are preferential dual prognostic predictors among TNBC patients.

Breast cancer disparities: Frontline strategies, proceedings of the 7 th annual texas conference on health disparities

There are striking disparities in health status, access to health care, and risk factors among racial and ethnic minorities and the general population in Texas. The disparities are multifactorial comprising genetic, sociocultural, and environmental variables. The Texas Center for Health Disparities (TCHD), a NIMHD Center of Excellence (COE), aims to prevent, reduce, and eliminate health disparities in the communities through research, education, and community-based programs. As part of the centers outreach activities, an annual conference is organized to build awareness and knowledge on health disparities. The overall theme for the 2012 conference was “Battling Breast Cancer Disparities: Frontline Strategies”. The scientific program consisted of three sessions: “Breakthroughs in Breast Cancer”, “Triple Negative Breast Cancer,” and “Hormone Resistant Breast Cancer” featuring different aspects of bench-research from molecular biology, proteomics, and genetics to the clinical aspects such as detection, diagnosis, and finally to community-based approaches. This article summarizes the proceedings of the meeting providing salient strategies and best practices presented by the speakers.

Abstract B03: Racial Variation in Annexin A2 (AnxA2) Gene Expression and Poor Outcome in Triple-Negative Breast Cancer

Background: Triple-negative breast cancer (TNBC) is identified by the absence of three major receptors (estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2)) that drive most breast cancers. The incidence of TNBC is associated with health disparity due to its disproportionate occurrence in African American (AA) women and its association with worst overall survival in AA women. Previously, our lab in breast cancer has investigated the prevalence, functionality, and mechanistic properties of one of the members of the human annexin family, Annexin A2 (AnxA2), a 36 kDa calcium-dependent phospholipid binding protein. Our previous studies and others have shown that AnxA2 is overexpressed in TNBC and has a reciprocal relationship with HER2 at mRNA and protein levels, but its association with racial variation and clinical outcomes is unknown. Methods: AnxA2 mRNA expression was evaluated in breast cancer subtypes from The Cancer Genome Atlas (TCGA) Breast Invasive Carcinoma (BRCA) mRNA database that includes 1,094 patients. Associations between clinical outcomes and AnxA2 gene expression were tested in a genome wide association study of combined publicly available microarray datasets that includes 4,147 patients (mean follow-up of 69 months). Two tissue microarrays (TMA) consisting of 154 breast cancer patient samples of various subtypes and forty archived paraffin-embedded breast tissues (TNBC and normal tissue) were collected from patients based on ethnicity and analyzed by immunohistochemistry and scored by a clinical pathologist in a blind study to provide scores (0,+1,+2,+3) based on AnxA2 staining intensity. Results: AnxA2 gene expression was significantly increased in TNBC in comparison to other breast cancer subtypes. Furthermore, AnxA2 gene expression was significantly elevated in AA (n=158) women in comparison with Caucasian (CA; n=654, P Conclusion: AnxA2 overexpression is associated with racial variation and is a potential prognostic and diagnostic candidate for TNBC. Impact: AnxA2 has potential prognostic and diagnostic value, implicating a role for AnxA2 in the aggressive biology of TNBC in AA women. Citation Format: Lee D. Gibbs, Pankaj Chaudhary, Jamboor K. Vishwanatha. Racial Variation in Annexin A2 (AnxA2) Gene Expression and Poor Outcome in Triple-Negative Breast Cancer. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B03.

Abstract 1426: Racial variation in annexin A2(AnxA2) gene expression and poor outcome in triple-negative breast cancer

Background: Triple-negative breast cancer (TNBC) is identified by the absence of three major receptors that drive most breast cancers. The incidence of TNBC is also associated with health disparity due to its disproportionate occurrence in African American (AA) women. Our previous studies and others have shown that AnxA2 is overexpressed in TNBC, but its association with racial variation and outcomes is unknown. Methods: AnxA2 gene expression was evaluated in breast cancer subtypes from The Cancer Genome Atlas (TCGA) Breast Invasive Carcinoma (BRCA) mRNA database that include 1,094 patients. Associations between clinical outcomes and AnxA2 gene expression were tested in a genome wide association study of combined publicly available datasets that include 4,147 patients. Results: AnxA2 gene expression was significantly increased in TNBC in comparison to other breast cancer subtypes. Furthermore, AnxA2 gene expression was significantly elevated in AA women in comparison with Caucasian (CA) women and was associated with the disproportionate occurrence of TNBC in AA women. High expression levels of AnxA2 was associated with reduced overall survival (hazard of death = 2.66; 95% confidence interval {CI] = 1.14 - 6.25, P = 0.0192), reduced relapse free survival (hazard of relapse = 1.45; 95% confidence interval {CI] = 1.12 – 1.89, P = 0.0051), and reduced distant metastasis free survival (hazard of metastasis = 1.7; 95% confidence interval {CI] = 1.00 – 2.91, P = 0.048). AnxA2 gene expression was not associated with poor outcome in other intrinsic breast cancer subtypes, such as Luminal A, Luminal B, and Her-2, indicating the specific association of AnxA2 with the aggressive behavior of TNBC. Conclusion: AnxA2 overexpression is associated with racial variation and is a potential prognostic candidate for TNBC. Impact: AnxA2 has potential prognostic value, implicating a role for AnxA2 in the aggressive biology of TNBC in AA women. Citation Format: Lee D. Gibbs, Jamboor K. Vishwanatha. Racial variation in annexin A2(AnxA2) gene expression and poor outcome in triple-negative breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1426.

Abstract 1677: Annexin A2 antibody inhibits the progression of triple-negative and herceptin-resistant breast cancer by blocking epidermal growth factor receptor functions

Short Description: Annexin A2 (AnxA2), a calcium-dependent phospholipid binding protein, is abundantly present at the surface of triple-negative and Herceptin-resistant breast cancer cells. Interactions between cell-surface AnxA2 and tyrosine kinase receptors have an important role in the tumour microenvironment and act together to enhance tumour growth. The mechanism supporting this role is still unknown. Methods: Triple-negative (MDA-MB-231) and Herceptin-resistant (JIMT-1) breast cancer cell lines were grown in complete DMEM and DMEM/F12 medium respectively, in a humidified incubator at 37°C with 5% CO 2 . The membrane function of AnxA2 was blocked by incubating cells with anti-AnxA2 antibodies. Western blotting, immunoprecipitation, immunofluorescence, 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), flow cytometry, Clonogenic, and wound-healing assays were performed in this study Results: We demonstrate that in triple-negative and Herceptin-resistant breast cancer cells a large amount of AnxA2 is specifically translocated to the outer membrane domain. In addition, AnxA2 interacts with extracellular domain of epidermal growth factor receptor (EGFR) at the cell surface and has an important role in cancer cell proliferation and migration by modulating EGFR functions. Blocking AnxA2 function at the cell surface by anti-AnxA2 antibody suppressed the EGF-induced EGFR tyrosine phosphorylation and internalization by blocking its homodimerization. Furthermore, addition of AnxA2 antibody significantly inhibited the EGFR-dependent PI3K-AKT and Raf-MEK-ERK downstream pathways under both EGF-induced and basal growth conditions, resulting in lower cell proliferation and migration. Conclusions: These studies indicate that association of AnxA2 with EGFR in the membrane domain might play a positive regulatory role in keeping EGFR signaling events in an activated state in triple negative and Herceptin-resistant breast cancer thus making AnxA2 an important therapeutic target. Citation Format: Pankaj Chaudhary, Lee Daniel Gibbs, Jamboor K. Vishwanatha. Annexin A2 antibody inhibits the progression of triple-negative and herceptin-resistant breast cancer by blocking epidermal growth factor receptor functions. [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 1677. doi:10.1158/1538-7445.AM2015-1677