Elena Martinez, PhD & Bernard Futscher, PhD (co-pis) University of Arizona Arizona Cancer Center 1U01CA153086

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1 Elena Martinez, PhD & Bernard Futscher, PhD (co-pis) University of Arizona Arizona Cancer Center 1U01CA153086

2 Hispanic population in U.S. is largely underserved and underrepresented in research studies and clinical trials. Compared to NHWs, Hispanic women are diagnosed with disease with less favorable prognosis: Younger Higher grade Larger tumors Later stage ER- and triple negative tumors More likely to die of their disease Refs: Miller, 2002; Li, 2002; Howe, 2006; Bauer, 2007; Martinez, 2007; Ooi, 2010

3 Breast cancer incidence rates have declined over time; but not among younger women. Overall proportion of breast cancer in women <40 y is 5.6%; 10.3% among Hispanics. Age at diagnosis among Hispanics is as much as ten years earlier vs. NHWs. Breast cancer risk factors differ by age of onset, including an apparent opposing effect of pregnancy. Brinton et al., 2008; Hedeen et al., 2001; Martinez et al., 2001

4 From Albrektsen s study of 1.7 m Norwegian women; reproduced in Pregnancyassociated breast cancer and Metastasis (Schedin, 2006)

5 Mortality Relative Risk Worse survival at 5 years in cases diagnosed within 5 years after childbirth. Greater number of births worse outcome. Worse outcome in part explained by >% of ERtumors (Phillips, 2004) Bladstrom, 2003

6 To compare the epidemiological characteristics and epigenetic profiles of breast cancer tumors diagnosed in the transient postpartum period vs. those outside this period. Hypothesis: Critical epigenetic changes become fixed in the breast epithelium following a pregnancy, which ultimately manifest phenotypically.

7 To define the risk factors, tumor sub-types, and clinicopathological characteristics associated with breast cancer occurring in the post-partum period relative to that outside this period in Hispanic women. To assess whether methylation of specific proteincoding gene promoters is more frequent in tumors that occur in the post-partum period vs. those occurring outside this period. To assess whether mirna genes are more likely to be epigenetically altered in tumors diagnosed in the postpartum period.

8 Binational Breast Cancer Study Estudio Binacional de Cáncer de Mama US PIs: E. Martinez P. Thompson M. Bondy Mexico PIs: A. Daneri M. Meza L.E. Gutierrez Funded by the Avon Foundation and The National Cancer Institute

9 Eligibility Diagnosis of incident invasive breast cancer within 24 months of interview Self-identified as Mexican or Mexican-American 18+ years of age at diagnosis Data and specimen collection Risk factor questionnaire Medical record abstraction for clinical & pathologic data DNA sample from saliva or blood Tumor tissue samples Completely annotated case series

10 Risk Factor Total U.S. Mexico Mean age dx Mean age menarche Mean no. births Mean age first birth Breastfeeding 68.1% 58.5% 79.9% HRT use 12.3% 14.9% 9.2% FamilyHx BC 13.6% 16.6% 10.1%

11 Giovanna Cruz, MS Mel and Enid Zuckerman College of Public Health

12 Established risk factors explain 36% of Hispanic BC cases vs. 75% for NHW pre-menopausal women (Hines, 2010) Hispanics have higher fertility rates than Non-Hispanic Whites (2.3 vs. 1.8) (Fertility of American Women, 2006). 1) Does pregnancy recency promote more aggressive tumors, resulting in increased mortality? 2) Are tumors that arise in the extended post-partum period phenotypically different than those outside the period of increased risk?

13 HER2 HER2- FISH <2.2 or IHC 0 or 1 or 1+ ER/PR ER- & PR- ER+ / PR + IHC 10% cells staining + Subtype TNBC ER+/PR+ HER2+ FISH 2.2 or IHC 3 or 3+ ER- & PR- ER+ / PR+ IHC 10% cells staining + HER2+

14 Variable Subtype All ER+/PR+ HER2+ TNBC Ever pregnant, n (%) 350 (91.4%) 196 (92.0%) 84 (91.3%) 70 (89.7%) Total full-term pregnancies (FTP), mean (SD) Age at first FTP*, mean (SD) years Age at last FTP*, mean (SD) years Time since last FTP*, mean (SD), years 2.8± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±6.8 >10 years, n (%) 195 (57.2%) 115 (61.2%) 39 (47.0%) 41 (58.6%) 10 years, n (%) 146 (42.8%) 73 (38.8%) 44 (53.0%) 29 (41.4%)

15 Time since last full-term pregnancy Age-adj. OR (95% CI) HER2+ Multiv. OR (95% CI) >10 years Ref. Ref. 10 years 2.86 ( ) 2.96 ( ) *Adjusted for age at diagnosis, age at first full-term pregnancy, age age at first full-term pregnancy, and study site.

16 Time since last full-term pregnancy Age-adj. OR (95% CI) HER2+ Multiv. OR (95% CI) Age-adj. OR (95% CI) TNBC Multiv. OR (95% CI) >10 years Ref. Ref. Ref. Ref. 10 years 2.86 ( ) 2.96 ( ) 1.05 ( ) 0.60 ( ) *Adjusted for age at diagnosis, age at first full-term pregnancy, age at first full-term pregnancy, and study site.

17 Results suggest that HER2+ tumors are more likely to be diagnosed in the 10-y period following a FTP than ER+/PR+ tumors. Results are important given that no recognized risk factors exist for HER2+ tumor subtypes. Results for TNBC are imprecise and probably need larger sample size to detect an effect, if one exists. Differences in tumor subtype among populations are likely influenced by differences in reproductive patterns.

18 In vitro model : 3 pairs of isogenic, normal, finite lifespan human mammary epithelial cells (HMEC) & their fibroblast counterparts (HMF) -isolated from 3 different individuals 48, 184, & 240 mirna: Non coding RNA 22nt length ~1000 in the human genome Important cell regulatory node - each mirna may control 100s of genes Often disrupted in cancer - including via epigenetic dysfunction

19 mirna Expression in Human Mammary Cell Types: High Interindividual Concordance Lower Concordance Between Cell Types mirna Expression mirna expression was determined by mirna-seq using Solexa sequencing technology

20 mirna DNA Methylation State of Human Mammary Cell Types: High Interindividual Concordance Lower Concordance Between Cell Types mirna DNA Methylation FB 184 FB 48 FB 240 HMEC 184 DNA methylation analysis via MeDIP-coupled microarray analysis using an in house custom-designed mirna promoter microarray HMEC 48 HMEC 240

21 Extracted DNA and RNA (total and mirna) from FFPE 10 sections, 10 microns each. Worked with pathologist to isolate tumor area. RNA yield: 40 ng/micron of tissue. DNA yield: 60 ng/micron of tissue. P. Thompson

22 Continue to extract DNA and RNA from FFPE tissue. Focusing on optimizing nucleic acid sample preparations. Baseline of measurement for mirnas is established. Ion Torrent PGM next generation DNA sequencer acquired in Dr. Futscher s lab.

23 F Wang, B Wertheim, R Zenuk, G Cruz, E Pond, L Cordova C Keppler, P Thompson, E Martínez, AL Amador