Abstract P6-07-04: Gene expression profiles of angiogenesis related cytokines and cognate receptors predict breast cancer progression and survival
Authors: Wittliff JL , Sereff SB , Smolenkova IA , Hameed ZR , Andres SA 
Published: May 2019

Background: Angiogenesis plays a critical role in breast cancer development, invasion and metastasis, and VEGF, TGFß1, and IL10 genes and their cognate receptors are implicated in cancer behavior, mediating membrane and microenvironment remodeling. Our goal is to assess relationships of expression of these genes in LCM-procured carcinoma cells from primary breast cancers with clinical outcomes to predict risk of recurrence.

Methods: Gene expression determined by microarray and qPCR, ER/PR quantified by radio-ligand binding or EIA, features of primary breast cancers and clinical outcomes were performed by univariable and multivariable Cox regressions, Kaplan Meier plots and LASSO with R software v3.2.5. Microarray analyses of ˜22,000 genes utilized RNA isolated, purified and amplified from LCM-procured carcinoma cells. Gene expression was validated by qPCR while molecular signatures were externally validated with SurvExpress (Aguirre-Gamboa et al. PLoS One e74250, 2013).

Results: Univariable Cox regression of microarray results of cytokines and cognate receptor genes revealed IL10 expression was significant for prediction of Progression Free (PFS) or Overall Survival (OS) using an adjusted p-value of ≥ 0.30 (discovery cut-off). Without regard to ER/PR status, Kaplan Meier plots confirmed IL10 or TGFß1 expression was significant for predicting PFS and OS. Using ER+ cancers, IL10 or VEGF expression was related to PFS while only IL10R was related to OS of ER- cancers using univariable Cox regression. Validation by qPCR using tissue curls disclosed independent expression of either TGFß1 or VEGF predicted PFS and OS while that of TGFß1Rwas only related to PFS. IL10R expression only predicted OS of breast cancer patients. Violin plots of qPCR results indicated elevated expression of each of these six genes in ER+ primaries without regard to outcome. Multivariable Cox regression analyses of expression levels of cytokine-receptor gene pairs revealed that IL10-IL10R co-expression was highly significant for predicting OS. Strongly supportive, backwards selection (R software v3.2.5) utilizing microarray expression levels derived a significant model (molecular signature) consisting of IL10, IL10R and VEGFR genes for predicting OS. External validation of this 3-gene subset was accomplished utilizing patient data collected on SurvExpress. A second clinically relevant signature predicting OS in PR+ breast cancers was detected when TGFß1R expression was included with these 3 genes. Finally, backwards selection of qPCR data derived a significant 3-gene model composed of IL10R, TGFß1 and VEGF for predicting PFS that was undeniably validated by SurvExpress.

Conclusions: Using gene expression results derived from microarray analyses of LCM-procured breast carcinoma cells of primary lesions and validated by qPCR, subsets of angiogenesis related genes were identified that predict a patient's risk of recurrence and overall survival. Expression of candidate genes appears to be related to either/both ER or PR protein status of the primary lesion. Collectively, results suggest that expression of certain angiogenesis related genes may serve as biomarkers for assessing prognosis of breast carcinomas thus impacting clinical management.

Citation Format: Wittliff JL, Sereff SB, Smolenkova IA, Hameed ZR, Andres SA. Gene expression profiles of angiogenesis related cytokines and cognate receptors predict breast cancer progression and survival [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-07-04.