Genome-wide association study in Chinese identifies novel loci for blood pressure and hypertension

Hypertension is a common disorder and the leading risk factor for cardiovascular disease and premature deaths worldwide. Genome-wide association studies (GWASs) in the European population have identified multiple chromosomal regions associated with blood pressure, and the identified loci altogether explain only a small fraction of the variance for blood pressure. The differences in environmental exposures and genetic background between Chinese and European populations might suggest potential different pathways of blood pressure regulation. To identify novel genetic variants affecting blood pressure variation, we conducted a meta-analysis of GWASs of blood pressure and hypertension in 11 816 subjects followed by replication studies including 69 146 additional individuals. We identified genome-wide significant (P < 5.0 × 10(-8)) associations with blood pressure, which included variants at three new loci (CACNA1D, CYP21A2, and MED13L) and a newly discovered variant near SLC4A7. We also replicated 14 previously reported loci, 8 (CASZ1, MOV10, FGF5, CYP17A1, SOX6, ATP2B1, ALDH2, and JAG1) at genome-wide significance, and 6 (FIGN, ULK4, GUCY1A3, HFE, TBX3-TBX5, and TBX3) at a suggestive level of P = 1.81 × 10(-3) to 5.16 × 10(-8). These findings provide new mechanistic insights into the regulation of blood pressure and potential targets for treatments.

Illusions and cloaks for surface waves

Ever since the inception of Transformation Optics (TO), new and exciting ideas have been proposed in the field of electromagnetics and the theory has been modified to work in such fields as acoustics and thermodynamics. The most well-known application of this theory is to cloaking, but another equally intriguing application of TO is the idea of an illusion device. Here, we propose a general method to transform electromagnetic waves between two arbitrary surfaces. This allows a flat surface to reproduce the scattering behaviour of a curved surface and vice versa, thereby giving rise to perfect optical illusion and cloaking devices, respectively. The performance of the proposed devices is simulated using thin effective media with engineered material properties. The scattering of the curved surface is shown to be reproduced by its flat analogue (for illusions) and vice versa for cloaks.

Functional analysis of single-nucleotide polymorphisms in the regulation of coactivator-associated arginine methyltransferase 1 expression and plasma homocysteine levels

BACKGROUND

Hyperhomocysteinemia is a risk factor for cardiovascular disease. Coactivator-associated arginine methyltransferase 1 (CARM1) participates in the synthesis of homocysteine, but whether the genetic variations regulate CARM1 expression and homocysteine levels remains unknown.

METHODS AND RESULTS

Functional analyses combined with an association study were conducted to identify the causal variant for CARM1 expression and homocysteine levels. Based on functional annotations obtained from Encyclopedia of DNA Elements, we selected 4 potentially functional single-nucleotide polymorphisms in the CARM1 gene and investigated their effect on CARM1 transcription levels in vivo. rs117569851, located in the promoter region of CARM1, as well as rs12460421 and rs4804544, was associated with CARM1 expression levels, and the last 2 single-nucleotide polymorphisms were discovered in high linkage disequilibrium with rs117569851 (r(2)=0.9 and 1.0) in our study sample. rs117569851 was further identified to be responsible for regulating CARM1 expression. The T allele disrupted the binding of early growth response-1, which led to the downregulation of transcriptional activity in vitro and CARM1 mRNA levels in vivo. In addition, rs117569851 was associated with plasma homocysteine levels in a Chinese population (n=406), with a 2.16 μmol/L decrease per copy of T allele.

CONCLUSIONS

The present study suggests that a noncoding variant in the CARM1-promoter functions as a regulator of gene transcription and homocysteine levels.

Lenses on curved surfaces

This Letter presents a theory that allows graded index lenses to be mapped onto arbitrary rotationally symmetric curved surfaces. Examples of the Luneburg and Maxwell fish-eye lens are given, for numerous surfaces, always resulting in isotropic permittivity requirements. The performance of these lenses is initially illustrated with full-wave simulations utilizing a waveguide structure. A transformation of the refractive index profiles is then performed to design surface-wave lenses, where the dielectric layer is not only isotropic but also homogenous, demonstrating the applicability and ease of fabrication.

[Prediction models for the 15 years risk of new-onset hypertension in Chinese people aged from 35 to 64 years old]

OBJECTIVE

To set up prediction models for the risk of new-onset hypertension in Chinese people and explore the risk scores to facilitate the clinical application.

METHODS

A cohort set up since 1992 with participants aged 35-64 years old from 11 provinces and cities of China was prospectively studied. Logistic regression was used to analyze the risk factors for the incidence of hypertension within 15 years and the prediction models and risk scores were developed with the regression coefficient. The performance of the prediction models were tested and compared with the Framingham model.

RESULTS

A total of 3 899 participants free from hypertension at baseline with 15 years follow-up were enrolled in the study. Within 15 years, 1 776 cases of incident hypertension were ascertained with a incidence rate of 45.6%. Two prediction models were set up with age, systolic blood pressure, diastolic blood pressure, BMI and the history of parental hypertension in the Model 1, while TG and HDL-C added on the basis of Model 1 in the Model 2. Good performance of discrimination and calibration was established in both models with significant difference in C statistics and no significant difference in net reclassification improvement (NRI) index.

CONCLUSION

The hypertension risk prediction models can be used to estimate an individual's absolute risk for hypertension and could facilitate the management of potential hypertension patients.

Effect of drinking on all-cause mortality in women compared with men: a meta-analysis

BACKGROUND

Alcoholic beverages are consumed by humans for a variety of dietary, recreational, and other reasons. It is uncertain whether the drinking effect on risk of all-cause mortality is different between women and men. We conducted a meta-analysis to evaluate the effect of drinking on the risk of all-cause mortality in women compared with men.

METHODS

We selected cohort studies with measures of relative risk (RR) and 95% confidence interval (CI) for all-cause mortality for drinkers versus nondrinkers by sex. Sex-specific RR and 95% CI were used to estimate the female-to-male ratio of RR (RRR) and 95% CI. Pooled estimates of RRR across studies were obtained by the fixed-effects model or the random-effects model (if heterogeneity was detected). Second-order fractional polynomials and random effects meta-regression models were used for modeling the dose-risk relationship.

RESULTS

Twenty-four studies were considered eligible. A total of 2,424,964 participants (male: 1,473,899; female: 951,065) were enrolled and 123,878 deaths (male: 76,362; female: 47,516) were observed. Compared with nondrinkers, the pooled female-to-male RRR for drinkers was 1.07 (95% CI: 1.02, 1.12). Subgroup analyses showed that the increased risk among female drinkers appeared to be consistent. J-shaped dose-response relationship was confirmed between alcohol and all-cause mortality in men and women, respectively. Moreover, the female-to-male RRR of all-cause mortality were 1.52 (95% CI: 1.01, 2.29), 1.95 (95% CI: 1.08, 3.49), and 2.36 (95% CI: 1.15, 4.88), respectively, for those who consumed 75, 90, and 100 g/day of alcohol.

CONCLUSIONS

Females had an increased risk for all-cause mortality conferred by drinking compared with males, especially in heavy drinkers. The present study suggested that female drinkers, particularly heavy drinkers, should moderate or completely reduce their level of consumption to have a health benefit.

Fabrication of single-crystal few-layer graphene domains on copper by modified low-pressure chemical vapor deposition

Few-layer graphene domains are fabricated by modified LPCVD on Cu and the growth mechanism is schematically shown in the figure.

Coffee, tea, and the risk of hip fracture: a meta-analysis

The present meta-analysis shows no clear association between coffee consumption and the risk of hip fractures. There was a nonlinear association between tea consumption and the risk of hip fracture. Compared to no tea consumption, drinking 1-4 cups of tea daily was associated with a lower risk of hip fracture.

INTRODUCTION

Prospective cohort and case-control studies have suggested that coffee and tea consumption may be associated with the risk of hip fracture; the results have, however, been inconsistent. We conducted a meta-analysis to assess the association between coffee and tea consumption and the risk of hip fracture.

METHODS

We performed systematic searches using MEDLINE, EMBASE, and OVID until February 20, 2013, without limits of language or publication year. Relative risks (RRs) with 95% confidence intervals (CI) were derived using random-effects models throughout all analyses. We conducted categorical, dose-response, heterogeneity, publication bias, and subgroup analyses.

RESULTS

Our study was based on 195,992 individuals with 9,958 cases of hip fractures from 14 studies, including six cohort and eight case-control studies. The pooled RRs of hip fractures for the highest vs. the lowest categories of coffee and tea consumption were 0.94 (95% CI 0.71-1.17) and 0.84 (95% CI 0.66-1.02), respectively. For the dose-response analysis, we found evidence of a nonlinear association between tea consumption and the risk of hip fracture (p(nonlinearity) < 0.01). Compared to no tea consumption, 1-4 cups of tea per day may reduce the risk of hip fracture by 28% (0.72; 95% CI 0.56-0.88 for 1-2 cups/day), 37% (0.63; 95% CI 0.32-0.94 for 2-3 cups/day), and 21% (0.79; 95% CI 0.62-0.96 for 3-4 cups/day).

CONCLUSIONS

We found no significant association between coffee consumption and the risk of hip fracture. A nonlinear association emerged between tea consumption and the risk of hip fracture; individuals drinking 1-4 cups of tea per day exhibited a lower risk of hip fractures than those who drank no tea. The association between 5 daily cups of tea, or more, and hip fracture risk should be investigated.

Assessments of jaw bone density at implant sites using 3D cone-beam computed tomography

OBJECTIVE

To assess the bone density of dental implant sites using CBCT and Simplant software, and establish a quantitative ranges for each bone quality classification according to the classification of bone quality proposed by Lekholm and Zarb.

PATIENTS AND METHODS

128 patients' jaw bone were scanned by CBCT, the images were reconstructed by the Simplant software. The bone density of 236 potential implant sites was measured and the results were recorded using Hounsfield units (HU)．The data was analyzed with SPSS 19.0 software package for Mann-Whitney U test.

RESULTS

The anterior mandible mean bone density was (679.6 ± 141.67) HU > anterior maxilla, (460.25 ± 136.42) HU and posterior mandible, (394.4 ± 128.37) HU > posterior maxilla, (229.62 ± 144.48) HU. Quantitative parameters ranged of the bone density according to CBCT as follows: Lekholm and Zarb classification Type D4 was less than 200 HU, Type D2 and Type D3 were more than 200HU and less than 600 HU, and Type D1 was more than 600 HU.

CONCLUSIONS

Anterior mandible has the highest mean bone density and posterior maxilla has the lowest mean bone density．It is, therefore, proposed that an objective classification which confirms the importance of a site-specific bone tissue evaluation prior to implant installation.

Abstract P4-12-04: Initial treatment and survival among elderly breast cancer patients by receipt of human epidermal growth factor receptor 2-targeted therapy: An analysis of US national data 2006-2009

BACKGROUND: There are few studies of initial treatment and survival among elderly, newly diagnosed breast cancer (BC) patients stratified by receipt of human epidermal growth factor receptor 2- (HER2-) targeted therapy.

METHODS: Using linked Surveillance, Epidemiology, and End Results (SEER) and Medicare claims and enrollment data from 2006-2009, women aged 65+ years with an incident diagnosis of BC (index date) in 2007 and no prior history of any other cancer were identified and followed to evaluate initial treatment and survival. Study patients were required to have continuous enrollment from 1 year before index (baseline period) through the end of the data window, disenrollment or death, whichever came first. Patients were classified as having received HER2-targeted therapy if they had any claim indicating trastuzumab or lapatinib following diagnosis. Demographics, initial treatment (within 4 months of diagnosis), and survival (proportion of patients who died during the study period) were evaluated by receipt of HER2-targeted therapy (and by age and stage among those who received HER2-targeted therapy). Kaplan-Meier (KM) survival curves and survival at 36 months were estimated by stage. Treatment included surgery, radiation, chemotherapy, biologic, and hormone therapy, and was evaluated among patients with &gt; 2 months of follow-up.

RESULTS: Among 11,238 female BC patients, 510 received HER2-targeted therapy (99.8% trastuzumab, 2.5% lapatinib) and 10,728 did not. Those who received HER2-targeted therapy were slightly younger at diagnosis (mean age 73 vs. 76, P&lt;0.01) and less likely to have positive estrogen receptor (ER+; 52.7 vs. 85.1%, P&lt;0.01) and progesterone receptor (PR+; 37.8 vs. 72.6%, P&lt;0.01) status. They were also more likely to be diagnosed at later stages (Stage III: 23.3 vs. 7.4%; Stage IV: 10.6 vs. 4.9%; P&lt;0.01). Patients with HER2-targeted therapy were less likely to receive surgery (87.5 vs. 91.9%; P = 0.06), radiation (39.0 vs. 43.2%; P&lt;0.01), or hormone therapy (6.9 vs. 16.8%, P&lt;0.01), but more likely to receive chemotherapy (69.8 vs. 12.6%, P&lt;0.01). Mortality was similar between the two groups (15.3% for HER2-targeted therapy vs. 16.1% for non HER2-targeted therapy, P = 0.71). Among patients receiving HER2-targeted therapy, increased age (P&lt;0.01) and later stage (P&lt;0.01) were associated with higher mortality. Older patients were more likely to receive hormone therapy (P = 0.02) and less likely to receive chemotherapy (P = 0.02) and surgery (P = 0.08). Patients in later stages were less likely to receive surgery (P&lt;0.01) or radiation (P&lt;0.01) and more likely to receive chemotherapy (P = 0.01) or hormone therapy (P = 0.05).

CONCLUSIONS: Elderly, newly diagnosed BC patients who received HER2-targeted therapy were younger than those who did not received HER2-targeted therapy. Initial treatment patterns varied between the two groups, but survival outcomes were similar. Among patients in the HER2-targeted therapy group, treatment characteristics also differed by disease stage and age.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-04.

Abstract P3-06-11: Disease and treatment characteristics of a large insured female population with advanced or metastatic breast cancer by receipt of HER2-targeted agents

This retrospective administrative claims study of women diagnosed with advanced or metastatic breast cancer (BC) compared clinical histories and BC treatment by receipt of HER2- targeted agents (2TA), disease stage, and age group.

Women ≥ 18 years, diagnosed with stage III or IV BC were selected from the 2008-2012 Truven Health MarketScan databases using ICD-9-CM codes on non-diagnostic medical claims corresponding to BC and local or distant metastases; date of first metastasis was the index date. Patients were followed until the earliest of end of enrollment, inpatient death or 12/31/2012. Those with &lt;12 months continuous enrollment (CE) or non-BC primary cancers pre-index, or HIV or pregnancy anytime were excluded. 2TA was defined as ≥1 medical or pharmacy claim for trastuzumab or lapatinib in the pre- or post-index periods. Study cohorts were women ± 2TA use, 2TA users with stage III and IV BC, and 2TA users age 18-44, 45-64, or 65+ at index. Index demographics, pre-index BC and clinical histories, and post-index BC treatments were compared using t-tests, one-way ANOVA, and chi-square statistics.

Of 30,660 eligible women, 14.4% received 2TA at sometime. Compared to non-2TA patients those with 2TA were younger (mean (SD) age 55 (11) vs. 59 (13) years; p≤0.001) and had significantly lower comorbidity burden. While pre-index BC was similar (48% each), 2TA patients had higher rates of pre-index BC surgery (20% vs. 17%), adjuvant/neoadjuvent chemotherapy (74% vs. 53%), radiation treatment (12% vs. 10%), and lower non-2TA biologics use (0% vs. 3%), all p&lt;0.005. Of the 2TA cohort with pre-index BC, 58% used 2TA pre-index. Also among 2TA patients, 57% had Stage III BC at index and 18% were 18-44, 68% 45-64 and 15% 65+. Pre-index BC diagnosis differed by index BC stage (30% III vs. 73% IV) and increased with age (44% 18-44, 48% 45-64, 54% 65+), both p&lt;0.001.

Of those with ≥ 3 months CE post-index, 2TA users had higher rates, p&lt;0.001 of BC surgery (53% vs. 47%), radiation (65% vs. 54%) and non-2TA antineoplastic treatment (AT: 89% vs. 83%), compared to non-2TA patients. Of those treated, 2TA users had a higher rate of chemotherapy use (85% vs. 58%), but lower use rates of hormone therapy (56% vs. 78%) and non-2TA biologics (5% vs. 8%), all p&lt;0.001. Receipt of post-index BC surgery was greater among 2TA stage III than stage IV patients (78% vs. 19%) and decreased with age (62% 18-44, 53% 45-64, 42% 65+), both p&lt;0.001. Post-index, stage III 2TA patients were more likely (p&lt;0.001) to have radiation therapy (72% vs. 56%), use 2TA agents post-index (97% vs. 91%), and other AT (92% vs. 84%) compared to stage IV 2TA patients. Radiation declined in the 2TA cohort post-index with increasing age (70%, 65%, 61%, p&lt;0.001). 2TA and AT use also declined with increasing age but these did not reach statistical significance.

Receipt of 2TA (vs. non-2TA) was significantly associated with younger age and receipt of pre- and post- BC treatments. Clinical history and BC treatment differences between these cohorts partly reflect differential treatment patterns of HER2- positive and HER2- negative BC patients. Treatment characteristics for the 2TA cohort differ by disease stage and age group.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-06-11.

Abstract P3-06-09: Survival among patients with hormone receptor positive (HR+)/human epidermal growth factor receptor 2 negative (HER2-) advanced breast cancer: A real-world observational study

Background: Little is known about real-world outcomes for patients with HR+/HER2- advanced breast cancer. This study examined mortality outcomes, and in particular variations across patients with different stages of cancer and different sequencing of endocrine and chemotherapy treatments.

Methods: This retrospective study linked medical and pharmacy claims (2008-2012) from a large national US health plan with a proprietary clinical cancer database containing physician-reported clinical data on patients with breast cancer. Patients included in the study had HR+ and HER2- status, and had stage III (S3) or IV (S4) cancer at initial diagnosis, or had developed metastases following initial diagnosis (MET). The first date of diagnosis of advanced cancer or the first date of metastases following initial diagnosis was designated as the index date. Health plan enrollment for 3 months pre- and ≥12-months post- index date was required; patients who died within 12 months after index date and were continuously enrolled in the health plan were retained. A 3-month baseline period assessed prior treatment; a variable follow-up (until disenrollment or 31 Oct 2012) assessed patterns of endocrine and chemotherapy treatments following the index date. Patient mortality was identified via a combination of Social Security mortality data and patient hospital discharge status from claims data. Chi-square tests compared proportions and t-tests compared means.

Results: The study population included 263 S3, 71 S4, and 317 MET patients. Average age at index date was 51.9 years for S3, 54.4 years for SIV, and 52.8 years for MET patients (P = 0.080). Over the entire observable follow-up, 3.4% of S3 (17 per 1000 patient-years), 22.5% of S4 (119 per 1000 patient years), and 10.7% of MET patients (22 per 1000 patient years) died (P≤0.010 for comparisons). Mortality over the 1-year after index date was 1.1%, 12.7%, and 5.1% in the S3, S4, and MET groups respectively (P&lt;0.001). Patients who died in the first year after index date survived on average until 5.8 months (S3), 4.5 months (S4), and 7.3 months (MET) following the metastatic index date. Among MET patients, mean time to death from initial breast cancer diagnosis was 35.7 months for MET patients without endocrine treatment prior to chemotherapy (n = 157), and 76.1 months for other MET patients (n = 160) (P = 0.002). For S4 patients without endocrine treatment prior to chemotherapy (n = 34), patients survived an average of 10.0 months from initial advanced breast cancer diagnosis while the remaining S4 patients (n = 37) survived an average of 14.8 months.

Conclusions: Among patients with HR+/HER2- advanced breast cancer, mortality rates varied by stage of disease, and length of survival varied across patients pre-treated with endocrine therapy prior to chemotherapy compared with other patients. Further investigation of drivers behind differences in mortality may reveal the extent to which initial disease severity and sequencing of chemotherapy and endocrine therapy drive these variations.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-06-09.

Abstract P3-06-10: All-cause resource use among elderly breast cancer patients by receipt of human epidermal growth factor receptor 2-targeted therapy: An analysis of US national data 2006-2009

BACKGROUND: There are few recent studies of all-cause resource use among elderly, newly diagnosed breast cancer (BC) patients by receipt of human epidermal growth factor receptor 2- (HER2-) targeted therapy.

METHODS: Using linked Surveillance, Epidemiology, and End Results (SEER) and Medicare claims and enrollment data from 2006-2009, women aged 65+ years with an incident diagnosis of BC (index date) in 2007 and no prior history of any other cancer were identified and followed to evaluate all-cause resource use. Study patients were required to have continuous enrollment from 1 year before index (baseline period) through the end of the data window, disenrollment or death, whichever came first. Patients were classified as having received HER2-targeted therapy if they had any claim indicating trastuzumab or lapatinib following diagnosis. Demographics and all-cause resource use (hospitalizations, hospital days, outpatient visits, physician/provider services, prescription drug use, skilled nursing facility [SNF] care, home health care, hospice care, and durable medical equipment) were evaluated by receipt of HER2-targeted therapy (and by stage and age among those treated with HER2-targeted therapy).

RESULTS: Among 11,238 female BC patients, 510 received HER2-targeted therapy (99.8% trastuzumab, 2.5% lapatinib) and 10,728 did not. Duration of follow-up was longer for the HER2- targeted therapy group (mean: 28.0 vs. 27.2 months, P = 0.06). Patients receiving HER2-targeted therapy were more likely to be hospitalized during follow-up (72.4% vs. 57.8%, P&lt;0.01), though they had fewer mean per-patient-per-month (PPPM) hospital days (0.38 vs. 0.49, P&lt;0.01). Almost all patients had an outpatient visit (100.0% and 97.3%, P&lt;0.01) and a physician/provider visit (100.0% and 99.6%, P = 0.42) during follow-up, though patients receiving HER2-targeted therapy experienced greater PPPM service use (mean outpatient visits 1.08 vs. 0.69, P&lt;0.01; mean physician/provider services 3.91 vs. 2.79, P&lt;0.01). Similar proportions of patients had prescription drug (61.2% vs. 57.7%, P = 0.12), SNF care (14.3% vs. 14.5%, P = 0.95), and hospice care (both 8.2%, P = 1.00) use. Among patients treated with HER2-targeted therapy, those with later stage cancer were more likely to receive SNF (8.6% [Stage I], 11.8% [Stage II], 16.8% [Stage III], 27.8% [Stage IV]; P&lt;0.01), home health (20.7%, 39.6%, 50.4%, 50.0%; P&lt;0.01), and hospice care (0.0%, 0.5%, 15.1%, 31.5%; P&lt;0.01), and had higher mean PPPM hospital days (0.23, 0.32, 0.47, 0.73; P&lt;0.01). Patients treated with HER2-targeted therapy aged 75+ were more likely to be hospitalized (64.7% [65-69], 73.3% [70-74], 79.4% [75+]; P = 0.01) and to receive SNF (12.4%, 10.0%, 21.3%; P = 0.01), home health (31.2%, 35.6%, 51.9%; P&lt;0.01), and hospice care (5.3%, 4.4%, 15.6%; P&lt;0.01).

CONCLUSIONS: Patients receiving HER2-targeted therapy were more likely to be hospitalized than those not receiving HER2-targeted therapy, although with fewer mean PPPM hospital days. Outpatient and physician visits also were more frequent in the HER2-targeted therapy group. Among those receiving HER2-targeted therapy, resource use was higher among those diagnosed at later stages and advanced ages.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-06-10.

Abstract PD3-5: Survival benefit conferred by the androgen receptor is lost in aromatase inhibitor treated breast cancer

Aromatase Inhibitors have proven to be most effective in the treatment of post-menopausal breast cancer. Their mode of action is to inhibit the synthesis of estrogen (estrone) by the aromatase enzyme Cyp 19 thereby blocking ligand-dependent activation of the estrogen receptor. What has not been addressed to date is how cells that are deprived of estrogen, may potentially, adapt to the more androgenic environment resulting from long-term treatment with AI therapy. Research from our lab has identified the homeobox protein, HOXC11, to be an indicator of poor response to endocrine therapy and development of metastasis. To further our understanding of HOXC11 and its role in the development of endocrine-resistance and metastatic spread we undertook an RNA-seq experiment to identify its target genes in resistant breast cancer. This analysis identified PSAP, IFIT1 and HSP90AA1. Both PSAP (an androgen agonist) and HSP90AA1 (AR chaperone) are closely associated with AR which led to further investigation into the role of HOXC11 in the development of steroidal adaptability in Letrozole-resistant breast cancer. We hypothesize that HOXC11 regulated expression of PSAP results in oncogenic activation of AR in an AI resistant setting. Our findings have shown that AI-resistant cell lines in vitro have significantly elevated levels of AR and that loss of HOXC11 results in concommitant decrease in AR mRNA. In AI resistance expression of HOXC11 results in upregulation/stabilization of AR by PSAP thus enabling the tumour to adapt to use androgenic steroids for cell proliferation. The anti-androgen, Bicalutamide, reduces cell proliferation and cell motility in AI resistant cell lines. Survival analysis of AR in a TMA (n = 488) indicates that AR confers a survival benefit in the tamoxifen treated population. This protective effect is diminished in patients receiving AI therapy and is reflected in the altered Hazard Ratio of AR from the total population (HR: 0.485) to the AI treated cohort (HR: 1.197). Secreted PSAP was readily detectable in breast cancer patient serum and associates significantly with expression of HOXC11 in matched patient tissue (∼20). PSAP is associated with poor response to endocrine therapy and metastatic spread of prostate cancer and as it is secreted it could potentially be used to monitor patients on AI who might benefit from dual targeted therapy treatment.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD3-5.

Abstract P3-06-08: Patterns of health care utilization and costs by chemotherapy and endocrine therapy sequencing among patients with hormone receptor positive (HR+)/HER2- negative advanced breast cancer

Background: Little is known about health care costs and health services utilization of patients with HR+/HER2- advanced breast cancer, particularly in relation to the order in which patient receive endocrine and chemotherapy treatments.

Methods: A proprietary database with physician-reported clinical data on patients with breast cancer was linked to medical and pharmacy claims (2008-2012) from a national US health plan. Patients included in the study had HR+ and HER2- status. Advanced cancer included stage III or IV (SIV) at initial diagnosis, or developed metastases following initial diagnosis. The first date of advanced cancer diagnosis or date of metastases following initial diagnosis was designated as the index date. Health plan enrollment for 3 months pre- and ≥12-months post- index date was required; patients who died within 12 months after index date and were continuously enrolled were retained. A 3-month baseline period assessed prior treatment; variable follow-up (until disenrollment or 31 Oct 2012) assessed patterns of endocrine and chemotherapy treatments following index date. All-cause and cancer-specific health care utilization and paid costs were assessed over 12-months following index date. Costs were calculated as per-patient-per-month (PPPM), and utilization measured as rates per patient-month. Cancer-related medication costs included drug costs for endocrine, chemotherapy, targeted therapy, and treatments for pain or chemotherapy-induced nausea/ vomiting. In addition, costs for anti-cancer systemic therapies (chemotherapy, endocrine, and targeted therapy) were calculated PPPM including costs for medication administration.

Results: Of 651 study patients, 65% initiated chemotherapy prior to initiating endocrine therapy (CH). Remaining patients (OT) either had no chemotherapy (n = 132 endocrine only, n = 16 neither endocrine nor chemotherapy), or used endocrine therapy prior to chemotherapy (n = 77). Compared with OT, the CH group had more office (4.04 vs. 2.68 visits, P&lt;0.001) and outpatient hospital visits (3.08 vs. 2.10 visits, P&lt;0.001). In addition, 56% of CH vs. 41% of OT had inpatient hospital admissions during the follow-up (P&lt;0.001; rate ratio 0.97, P = NS). Similarly, 60% of CH patients were admitted to emergency rooms vs. 51% of OT (P = 0.033; rate ratio 1.01, P = NS). Mean total all-cause health care costs varied ($11,525 CH vs. $8,196 OT, P&lt;0.001). The largest source of difference in costs were office visits (mean $3,257 CH vs. $1,896 OT, P&lt;0.001), and outpatient hospital ($5,813 CH vs. $3,721 OT, P&lt;0.001). Cancer-related costs comprised the majority of costs (mean $10,249 CH vs. $7,118 OT, P&lt;0.001). The CH group had higher mean cancer-related medication costs than the OT group ($2,051 vs. $1,405 respectively, P = 0.040). Overall mean anti-cancer systemic therapy costs (including administration) were higher in the CH than OT group ($2,934 vs. $1,875, P = 0.012).

Conclusions: Among HR+/HER2- advanced breast cancer patients, health care utilization and costs were higher for patients who initiated chemotherapy prior to endocrine therapy compared to other patients. Further investigation of the drivers behind these differences is warranted.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-06-08.