Michael D. Stone

Gene expression abnormalities in histologically normal breast epithelium of breast cancer patients

Normal‐appearing epithelium of cancer patients can harbor occult genetic abnormalities. Data comprehensively comparing gene expression between histologically normal breast epithelium of breast cancer patients and cancer‐free controls are limited. The present study compares global gene expression between these groups. We performed microarrays using RNA from microdissected histologically normal terminal ductal‐lobular units (TDLU) from 2 groups: (i) cancer normal (CN) (TDLUs adjacent to untreated ER+ breast cancers (n = 14)) and (ii) reduction mammoplasty (RM) (TDLUs of age‐matched women without breast disease (n = 15)). Cyber‐T identified differentially expressed genes. Quantitative RT‐PCR (qRT‐PCR), immunohistochemistry (IHC), and comparison to independent microarray data including 6 carcinomas in situ (CIS), validated the results. Gene ontology (GO), UniProt and published literature evaluated gene function. About 127 probesets, corresponding to 105 genes, were differentially expressed between CN and RM (p < 0.0009, corresponding to FDR <0.10). 104/127 (82%) probesets were also differentially expressed between CIS and RM, nearly always (102/104 (98%)) in the same direction as in CN vs. RM. Two‐thirds of the 105 genes were implicated previously in carcinogenesis. Overrepresented functional groups included transcription, G‐protein coupled and chemokine receptor activity, the MAPK cascade and immediate early genes. Most genes in these categories were under‐expressed in CN vs. RM. We conclude that global gene expression abnormalities exist in normal epithelium of breast cancer patients and are also present in early cancers. Thus, cancer‐related pathways may be perturbed in normal epithelium. These abnormalities could be markers of disease risk, occult disease, or the tissues response to an existing tumor.

Gene expression in histologically normal epithelium from breast cancer patients and from cancer-free prophylactic mastectomy patients shares a similar profile

Introduction:We hypothesised that gene expression in histologically normal (HN) epithelium (NlEpi) would differ between breast cancer patients and usual-risk controls undergoing reduction mammoplasty (RM), and that gene expression in NlEpi from cancer-free prophylactic mastectomy (PM) samples from high-risk women would resemble HN gene expression.Methods:We analysed gene expression in 73 NlEpi samples microdissected from frozen tissue. In 42 samples, we used microarrays to compare gene expression between 18 RM patients and 18 age-matched HN (9 oestrogen receptor (ER)+, 9 ER−) and 6 PM patients. Data were analysed using a Bayesian approach (BADGE), and validated with quantitative real-time PCR (qPCR) in 31 independent NlEpi samples from 8 RM, 17 HN, and 6 PM patients.Results:A total of 98 probe sets (86 genes) were differentially expressed between RM and HN samples. Performing hierarchical analysis with these 98 probe sets, PM and HN samples clustered together, away from RM samples. qPCR validation of independent samples was high (84%) and uniform in RM compared with HN patients, and lower (58%), but more heterogeneous, in RM compared with PM patients. The 86 genes were implicated in many processes including transcription and the MAPK pathway.Conclusion:Gene expression differs between the NlEpi of breast cancer cases and controls. The profile of cancer cases can be discerned in high-risk NlEpi from cancer-free breasts. This suggests that the profile is not an effect of the tumour, but may mark increased risk and reveal the earliest genomic changes of breast cancer.

Early Dysregulation of Cell Adhesion and Extracellular Matrix Pathways in Breast Cancer Progression

Proliferative breast lesions, such as simple ductal hyperplasia (SH) and atypical ductal hyperplasia (ADH), are candidate precursors to ductal carcinoma in situ (DCIS) and invasive cancer. To better understand the relationship of breast lesions to more advanced disease, we used microdissection and DNA microarrays to profile the gene expression of patient-matched histologically normal (HN), ADH, and DCIS from 12 patients with estrogen receptor positive sporadic breast cancer. SH were profiled from a subset of cases. We found 837 differentially expressed genes between DCIS-HN and 447 between ADH-HN, with >90% of the ADH-HN genes also present among the DCIS-HN genes. Only 61 genes were identified between ADH-DCIS. Expression differences were reproduced in an independent cohort of patient-matched lesions by quantitative real-time PCR. Many breast cancer-related genes and pathways were dysregulated in ADH and maintained in DCIS. Particularly, cell adhesion and extracellular matrix interactions were overrepresented. Focal adhesion was the top pathway in each gene set. We conclude that ADH and DCIS share highly similar gene expression and are distinct from HN. In contrast, SH appear more similar to HN. These data provide genetic evidence that ADH (but not SH) are often precursors to cancer and suggest cancer-related genetic changes, particularly adhesion and extracellular matrix pathways, are dysregulated before invasion and even before malignancy is apparent. These findings could lead to novel risk stratification, prevention, and treatment approaches.

The Effect of a Cognitive Behavioral Exercise Intervention on Clinical Depression in a Multiethnic Sample of Women With Breast Cancer: A Randomized Controlled Trial

Abstract Exercise is known to facilitate physical and emotional adjustment among women treated for breast cancer, and exercise exerts a profound effect on clinical depression. However, the effect of exercise on reducing clinical depression among breast cancer patients has not been demonstrated, especially among ethnic minority women who have a higher incidence of depression and higher mortality following breast cancer. First, literature is presented to assess exercise effects on depression among women with breast cancer. Second, we present the results of a randomized controlled trial assessing the effect of a structured exercise intervention on depression and exercise behavior in a multiethnic sample of women with early stage breast cancer enrolled prior to the start of adjuvant treatment. Results suggest that, in comparison to population norms, the rate of depression was higher in breast cancer patients. Analyses further showed that the intervention significantly increased self‐reported exercise and reduced depression. These data suggest that the beneficial effects of exercise may extend to breast cancer patients with depression and may be initiated prior to and during cancer treatment

Cone-beam computed tomography image guided therapy to evaluate lumpectomy cavity variation before and during breast radiotherapy

The purpose of this study was to evaluate the rate of change (RoC) in the size of the lumpectomy cavity (LC) before and during breast radiotherapy (RT) using cone‐beam computed tomography (CBCT), relative to the initial LC volume at CT simulation (CTVLC) and timing from surgery. A prospective institutional review board‐approved study included 26 patients undergoing breast RT: 20 whole breast irradiation (WBI) patients and six partial breast irradiation (PBI) patients, with surgical clips outlining the LC. The patients underwent CT simulation (CTsim) followed by five CBCTs during RT, once daily for PBI and once weekly for WBI. The distance between surgical clips and their centroid (D) acted as a surrogate for LC size. The RoC of the LC size, defined as the percentage change of D between two scans divided by the time interval in days between the scans, was calculated before (CTsim to CBCT1) and during RT (CBCT1 to CBCT5). The mean RoC of D for all patients before starting RT was −0.25%/day (range, −1.3 to 1.4) and for WBI patients during RT was −0.15%/day (range, −0.45 to 0.40). Stratified by median CTVLC, the RoC before RT for large CTVLC group (≥25.7cc) was 15 times higher (−0.47%/day) than for small CTVLC group (<25.7 cc) (−0.03%/day), p=0.06. For patients undergoing CTsim < 42 days from surgery, the RoC before RT was −0.43%/day compared to −0.07%/day for patients undergoing CTsim≥42 days from surgery, p=0.12. For breast cancer RT, the rate of change of the LC is affected by the initial cavity size and the timing from surgery. Resimulation closer to the time of boost treatment should be considered in patients who are initially simulated within six weeks of surgery and/or with large CTVLC. PACS number: 87.55.de