Does everyday discrimination account for the increased risk of vasomotor symptoms in Black women?: the Study of Women's Health Across the Nation (SWAN)

OBJECTIVES

Vasomotor symptoms (VMS), including hot flashes and night sweats, are hallmark symptoms of the menopause transition. Previous research has documented greater frequency, duration, and severity of VMS in Black women compared with women from other racial/ethnic groups, even after accounting for other factors. This analysis examined the association between discrimination and VMS and the extent to which discrimination accounts for the disproportionate burden of VMS in Black women.

METHODS

Using available discrimination and VMS data from the SWAN cohort study (n = 2,377, 48% White, 32% Black, 6% Japanese, 4% Chinese, and 9% Hispanic women) followed approximately yearly in midlife from premenopause (42-52 y) through postmenopause (~20 y), we assessed concurrent associations between discrimination and VMS frequency in the past 2 weeks using weighted generalized mixed models. We also assessed associations between chronic discrimination across first four visits and VMS trajectories from premenopause to postmenopause using weighted multinomial logistic regression. Models were adjusted for known risk factors for VMS.

RESULTS

Higher levels of discrimination were associated with concurrent reporting of any (odds ratio [OR], 1.57 [1.31-1.89]) and frequent (≥6 d) VMS (OR, 1.55 [1.21-1.99]). After adjustment, associations remained significant for any (OR, 1.30 [1.09-1.54]) but not frequent VMS. For any VMS trajectories, chronic discrimination was associated with "continuously high" (OR, 1.69 [1.03-2.77]) and "high pre-FMP-decline post-FMP" (OR, 1.70 [1.01-2.88]) versus "FMP-onset low" trajectories. After adjusting for discrimination, odds of reporting any, frequent, and of being in the "continuously high" any VMS trajectory remained elevated for Black versus White women.

CONCLUSIONS

Discrimination is associated with greater concurrent risk of any (but not frequent) VMS, and chronic discrimination is associated with a continuously high reporting of any VMS over time, independent of known risk factors. Adjusting for discrimination attenuates but does not eliminate the increased risk of VMS for Black women.

A Large-Scale Genome-Wide Study of Gene-Sleep Duration Interactions for Blood Pressure in 811,405 Individuals from Diverse Populations

Although both short and long sleep duration are associated with elevated hypertension risk, our understanding of their interplay with biological pathways governing blood pressure remains limited. To address this, we carried out genome-wide cross-population gene-by-short-sleep and long-sleep duration interaction analyses for three blood pressure traits (systolic, diastolic, and pulse pressure) in 811,405 individuals from diverse population groups. We discover 22 novel gene-sleep duration interaction loci for blood pressure, mapped to genes involved in neurological, thyroidal, bone metabolism, and hematopoietic pathways. Non-overlap between short sleep (12) and long sleep (10) interactions underscores the plausibility of distinct influences of both sleep duration extremes in cardiovascular health. With several of our loci reflecting specificity towards population background or sex, our discovery sheds light on the importance of embracing granularity when addressing heterogeneity entangled in gene-environment interactions, and in therapeutic design approaches for blood pressure management.

Sleep timing, sleep regularity, and psychological health in early late life women: Findings from the Study of Women's Health Across the Nation (SWAN)

OBJECTIVES

To examine the associations of actigraphy-assessed sleep timing and regularity with psychological health in early late life women, whose circadian rhythms may be impacted by aging.

DESIGN

Cross-sectional.

PARTICIPANTS

A racially/ethnically diverse sample of 1197 community-dwelling women (mean age 65 years) enrolled in the Study of Women's Health Across the Nation.

MEASURES

Actigraphy-assessed sleep measures included timing (mean midpoint from sleep onset to wake-up) and regularity (standard deviation of midpoint in hours). Psychological health measures included a composite well-being score, the Center for Epidemiological Studies Depression Scale, and the Generalized Anxiety Disorder-7 Scale. Linear and logistic regression models, adjusted for covariates (including sleep duration), tested associations between sleep and psychological health measures.

RESULTS

After covariate adjustment, a sleep midpoint outside of 2:00-4: 00 AM was significantly associated with depressive symptoms (β = 0.88, 95% CI = 0.06, 1.70) and scoring above the cut-point for clinically significant depressive symptoms (OR = 1.72, 95% CI = 1.15, 2.57). Sleep irregularity was significantly associated with lower psychological well-being (β = -0.18, 95% CI = -0.33, -0.03), depressive (β = 1.36, 95% CI = 0.29, 2.44) and anxiety (β = 0.93, 95% CI = 0.40, 1.46) symptoms, and scoring above the cut-point for clinically significant depressive (OR = 1.68, 95% CI = 1.01, 2.79) and anxiety (OR = 1.62, 95% CI = 1.07, 2.43) symptoms.

CONCLUSION

Above and beyond sleep duration, a sleep midpoint outside of 2:00-4:00 AM was associated with depressive symptoms while sleep irregularity was associated with multiple psychological health domains in late life women.

Disparities in Vision Impairment and Eye Diseases among Early Late-Life Women: The Study of Women's Health Across the Nation, Michigan Site

OBJECTIVE

To quantify the burden of vision impairment (VI) and ocular conditions among early late-life women.

METHODS

Women (n = 254, mean age 66.0 years) participated in a comprehensive vision assessment. Visual acuity (VA) and ocular disorders (diabetic retinopathy, macular degeneration, hypertensive retinopathy, glaucoma and cataracts) were defined clinically. Race, economic strain and education were self-reported.

RESULTS

The prevalence of presenting VI (VA 20/40 or worse) was 11.0% and 75% of that was correctable (best-corrected VI 2.8%). Black women and those with greater economic strain or less education had a higher prevalence of presenting VI. These disparities were no longer present after considering best-corrected VI. Ocular disease prevalence ranged from 3.3% (age-related macular degeneration) to 30.2% (hypertensive retinopathy), but most participants were unaware of their ocular diagnosis.

CONCLUSION

The discordance of presenting versus best-corrected VI and lack of knowledge of ocular conditions suggests a need for increased vision services. Access to optimal vision correction may attenuate differences across sociodemographic groups.

Midlife Vision Impairment and Cognitive Function in Later Life: The Study of Women's Health Across the Nation, Michigan Cohort

BACKGROUND

In older adults, vision impairment (VI) is associated with worse cognitive function. However, the relationship between midlife vision and future cognitive function remains unknown.

METHODS

The Study of Women's Health Across the Nation, Michigan site, is a longitudinal cohort of midlife women aged 42-52 years at baseline. Presenting Titmus visual acuity (VA) in the better-seeing eye was assessed at baseline and categorized as no or mild VI (VA ≥20/60), or moderate or worse VI (VA <20/60). Cognitive function was measured 8 times over 15 years using the East Boston Memory Test immediate (EBMTi) and delayed (EBMTd) recall and the Digit Span Backwards (DSB) test. Linear mixed models with a random intercept and slope for age were constructed to detect associations between VI at baseline and future repeated measures of cognitive function, adjusting for age, race, education, financial strain, alcohol use, and tobacco use.

RESULTS

About 394 women aged 42-52 at baseline with a maximum follow-up of 20 years were included in this analysis. After covariate adjustment, moderate or worse VI was associated with lower EMBTi (β = -0.56, p = .012), EBMTd (β = -0.60, p = .009), and DSB (β = -0.84, p = .04). While we detected significant associations between VI and levels of cognitive function scores, rates of cognitive decline as individuals aged did not vary by VI status.

CONCLUSION

Moderate or worse VI, assessed during midlife, was associated with lower scores on measures of cognitive function over a 15-year period during which women transitioned from midlife to older adulthood.

Longitudinal association of midlife vision impairment and depressive symptoms: the study of Women's Health Across the Nation, Michigan site

OBJECTIVE

Poor vision affects physical health but the relationship with depressive symptoms among midlife adults (40-65 y), who often present with early stage vision impairment (VI), is not well understood. The goal of this study was to assess the impact of vision on depressive symptoms during midlife.

METHODS

The Michigan site of the Study of Women's Health Across the Nation conducted assessments of distance visual acuity at six consecutive, near-annual follow-up visits. At each visit, depressive symptoms (Center for Epidemiological Studies-Depression Scale) were assessed. VI was defined as mild (20/30-20/60) or moderate-severe (20/70 or worse). Multivariable logistic regression models using generalized estimating equations were used to assess the association of VI and reporting of depressive symptoms at the subsequent visit.

RESULTS

At analytic baseline, the mean age of participants (N = 226) was 50.0 years (standard deviation = 2.6). More than half (53.5%) of women had mild VI and 8.0% had moderate-severe VI. Adjusting for age, preexisting depressive symptoms, race, education, economic strain, body mass index, and smoking, participants with mild and moderate-severe VI had 68% (95% C (0.97-2.90)) and 2.55-fold (95% CI 1.13-5.75) higher odds of reporting depressive symptoms at their subsequent study visit as compared with women without VI. Further adjustment for diabetes, hypertension, and osteoarthritis attenuated the estimates and the associations were no longer statistically significant.

CONCLUSION

VI was associated with increased odds of future depressive symptoms among mid-life women. Timely detection and appropriate correction of VI may be important to consider in maintaining the mental health status of midlife women.

Per- and Polyfluoroalkyl Substances and Hormone Levels During the Menopausal Transition

CONTEXT

Per- and polyfluoroalkyl substances (PFAS) are widespread chemicals that may affect sex hormones and accelerate reproductive aging in midlife women.

OBJECTIVE

To examine associations between serum PFAS concentrations at baseline (1999-2000) and longitudinal serum concentrations of follicle-stimulating hormone (FSH), estradiol, testosterone, and sex hormone-binding globulin (SHBG) at baseline and through 2015-2016.

DESIGN

Prospective cohort.

SETTING

General community.

PARTICIPANTS

1371 midlife women 45 to 56 years of age at baseline in the Study of Women's Health Across the Nation (SWAN).

MAIN OUTCOME MEASURE(S)

FSH, estradiol, testosterone, SHBG.

RESULTS

In linear mixed models fitted with log-transformed hormones and log-transformed PFAS adjusting for age, site, race/ethnicity, smoking status, menopausal status, parity, and body mass index, FSH was positively associated with linear perfluorooctanoate [n-PFOA; 3.12% (95% CI 0.37%, 5.95%) increase for a doubling in serum concentration), linear perfluorooctane sulfonate [PFOS; 2.88% (0.21%, 5.63%)], branched perfluorooctane sulfonate [2.25% (0.02%, 4.54%)], total PFOS (3.03% (0.37%, 5.76%)), and 2-(N-ethyl-perfluorooctane sulfonamido) acetate [EtFOSAA; 1.70% (0.01%, 3.42%)]. Estradiol was inversely associated with perfluorononanoate [PFNA; -2.47% (-4.82%, -0.05%)) and n-PFOA (-2.43% (-4.97%, 0.18%)]. Significant linear trends were observed in the associations between PFOS and EtFOSAA with SHBG across parity (Ps trend ≤ 0.01), with generally inverse associations among nulliparous women but positive associations among women with 3+ births. No significant associations were observed between PFAS and testosterone.

CONCLUSIONS

This study observed positive associations of PFOA and PFOS with FSH and inverse associations of PFNA and PFOA with estradiol in midlife women during the menopausal transition, consistent with findings that PFAS affect reproductive aging.

Paper towel test as independently self-administered to quantify cough-related urine loss: Compliance and comparisons with survey-only data in SWAN

AIMS

The epidemiologic Study of Women's Health Across the Nation (SWAN) includes urinary incontinence (UI) questionnaire items. We introduced an independently self-administered paper towel test (PTT-ISA; invention disclosure #2021-347) to objectively demonstrate UI. Aims were to determine: (1) PTT-ISA compliance and (2) relationship to questionnaire results.

METHODS

276 community women were invited to complete both SWAN questionnaire and PTT-ISA. For PTT-ISA, a woman holds a trifold brown paper towel against her perineum while coughing hard three times. She checks the towel for wetness and compares it with pictorial showing wetted area gradations (dry towel through >6 ml/saturated). She then selects the best photo match for her towel. A newly conceptualized variable constructed as PTT-ISA plus questionnaire results was formed.

RESULTS

Of 276 women, noncompliance with PTT-ISA was 2.2% (6 women). Four others (1.5%) were missing questionnaires. For the remaining 266 women, conceptual cohesiveness between questionnaire-only and PTT-ISA + questionnaire was demonstrated in 165 (62.0%). Lack of cohesiveness occurred in 101 (38.9%), including 41 women who said "no" to the questionnaire item indicative of stress UI and had leakage on PTT-ISA; leakage degree varied across the full pictorial spectrum from drops to saturated.

CONCLUSION

PTT-ISA demonstrates high compliance, with rate comparable to survey compliance. It is a novel measure for objective sign of urine loss when independently self-administered by community women outside of a clinic environment. Further research comparing PTT-ISA with clinician-observed cough test is warranted. As independently self-administered, PTT-ISA is simple, noninvasive, inexpensive, and an acceptable test that adds value to otherwise survey-dependent research.

Associations between sleep and cognitive performance in a racially/ethnically diverse cohort: the Study of Women's Health Across the Nation

STUDY OBJECTIVES

To determine whether actigraphy-assessed indices of sleep are associated with cognitive performance in women, and explore whether these associations vary by race/ethnicity.

METHODS

Participants were 1,126 postmenopausal community-dwelling females (mean age 65 years) from the observational Study of Women's Health Across the Nation (SWAN); 25% were black, 46% white, 13% Chinese, 11% Japanese, and 5% Hispanic. Actigraphy-assessed sleep measures included total sleep time, wake after sleep onset (WASO), and fragmentation. Cognitive measures included immediate and delayed verbal memory, working memory, and information processing speed. All measures were assessed in conjunction with SWAN annual visit 15.

RESULTS

Across the sample, after covariate adjustment, greater WASO and fragmentation were concurrently associated with slower information processing speed. Black participants had significantly worse sleep relative to other race/ethnic groups. Significant race/sleep interactions were observed; in black, but not white, participants, greater fragmentation was concurrently associated with worse verbal memory and slower information processing speed, and greater WASO was concurrently associated with slower information processing speed. Sleep-cognitive performance associations were not different in Chinese and Japanese participants relative to white participants.

CONCLUSIONS

Greater wakefulness and fragmentation during sleep are concurrently associated with slower information processing. Sleep continuity impacted concurrent cognitive performance in black, but not white, women. This effect may not have been detected in white women because their sleep was largely within the normal range. Future longitudinal studies in diverse samples are critical to further understand whether race/ethnicity moderates the influence of sleep on cognitive performance.

Genetic variants predictive of reproductive aging are associated with vasomotor symptoms in a multiracial/ethnic cohort

OBJECTIVE

Vasomotor symptoms (VMS), hot flashes, and night sweats are cardinal symptoms of the menopausal transition. Little is known about genetic influences on VMS. This study evaluated whether previously identified genetic factors predictive of VMS, age at menarche, and age at menopause were associated with VMS in a multiracial/ethnic cohort.

METHODS

For 702 White, 306 Black, 126 Chinese, and 129 Japanese women from the Study of Women's Health Across the Nation (SWAN) Genomic Substudy, we created polygenic risk scores (PRSs) from genome-wide association studies of VMS and ages at menarche and menopause. PRSs and single nucleotide polymorphisms (SNPs) from a previously identified VMS locus (tachykinin receptor 3 [TACR3]) were evaluated for associations with frequent VMS (VMS ≥6 days in the past 2 weeks at any visit) and with VMS trajectories (persistently low, early onset, final menstrual period onset, persistently high).

RESULTS

The C-allele of rs74827081 in TACR3 was associated with reduced likelihood of frequent VMS in White women (odds ratio [OR] = 0.49 [95% CI, 0.29-0.83]). With higher menarche PRS (later menarche), Black women were less likely (OR = 0.55 [95% CI, 0.38-0.78]) to report frequent VMS. With higher PRS for age at menarche, Black women were also less likely to have a persistently high VMS trajectory (OR = 0.55 [95% CI, 0.34-0.91]), whereas White women (OR = 0.75 [95% CI, 0.58-0.98]) were less likely to have a final menstrual period onset trajectory (vs persistently low). Chinese women with higher menopause PRS were more likely to have frequent VMS (OR = 2.29 [95% CI, 1.39-3.78]). Associations were substantively similar after excluding rs74827081 C-allele carriers.

CONCLUSIONS

Genetic factors predictive of reproductive aging are also associated with VMS, suggesting that VMS have a polygenic architecture. Further study in this area may help to identify new targets for novel VMS therapies.

Associations between polygenic risk score for age at menarche and menopause, reproductive timing, and serum hormone levels in multiple race/ethnic groups

OBJECTIVE

We assessed associations of genetic loci that contribute to age at menarche and menopause with sentinel menopausal traits in multiple race/ethnic groups.

METHODS

Genetic data from the Study of Women's Health Across the Nation include 738 White, 366 Black, 139 Chinese, and 145 Japanese women aged 42 to 52 at baseline. We constructed standardized polygenic risk scores (PRSs) using single nucleotide polymorphisms identified from large-scale genome-wide association studies meta-analyses of ages at menopause and menarche, evaluating associations with each trait within each race/ethnic group.

RESULTS

Menopause PRS was significantly associated with age at menopause in White women after Bonferroni correction (P < 0.004) and nominally associated in Chinese and Japanese women (P < 0.05) (7.4-8.5 mo delay for one standard deviation [SD] increase in PRS). Menarche PRS was significantly associated with age at menarche in White (P < 0.004) and nominally associated in Black and Japanese women (P < 0.05) (2.6-4.8 mo delay for one SD increase). In White women, menarche and menopause PRSs were significantly associated (P < 0.004) with shorter and longer (5.9 and 9.6 mo for one SD increase) reproductive lifespans, respectively, and menopause PRS with a longer menopausal transition (7.1 mo for one SD increase). We observed a significant positive association (P < 0.004) between menopause PRS and E2 level 2 years before menopause and a nominal association (P < 0.05) 2 years after menopause in Japanese women.

CONCLUSIONS

In addition to menopausal timing, PRSs associated with onset and ending of reproductive life were associated with reproductive lifespan, length of the menopausal transition, and E2 levels in different race/ethnic groups.

Symptom clusters predict risk of metabolic-syndrome and diabetes in midlife: the Study of Women's Health Across the Nation

PURPOSE

Women's cardio-metabolic risk increases in midlife. Previous work relating menopause symptoms to diabetes/Metabolic Syndrome (MetS) does not consider the adverse impact of multiple concurrent physical and psychological symptoms in midlife.

METHODS

Data are from 3097 participants in the Study of Women's Health Across the Nation, a cohort of midlife women followed for over 20 years. Baseline latent symptom classes (LSC) were derived from 58 questions assessing physical, psychological and menopausal symptoms. Six identified LSCs ranged from 1 (most symptoms present at high severity) to 6 (few symptoms present at low severity). Accelerated failure time models estimated time to onset of type 2 diabetes and MetS for each LSC.

RESULTS

Women with multiple high/moderate severity symptoms had an earlier onset of diabetes (13.2%, 14.1% and 20.8% earlier onset in LSCs 1, 2, 3, respectively) and MetS (15.5%, 13.0% and 19.7% earlier onset in LSCs 1, 2, 3, respectively) than women with few/low severity symptoms.

CONCLUSIONS

Having multiple concurrent moderate to high intensity physical and psychological symptoms in midlife are associated with early onset of diabetes and MetS. Monitoring and subsequent intervention on a broad range of symptoms in midlife may significantly mitigate cardio-metabolic risk during this critical life stage.

Healthy Lifestyle During the Midlife Is Prospectively Associated With Less Subclinical Carotid Atherosclerosis: The Study of Women's Health Across the Nation

Background

Measures of subclinical atherosclerosis are predictors of future cardiovascular outcomes as well as of physical and cognitive functioning. The menopausal transition is associated with accelerated progression of atherosclerosis in women. The prospective association between a healthy lifestyle during the midlife and subclinical atherosclerosis is unclear.

Methods and Results

Self‐reported data on smoking, diet, and physical activity from 1143 women in the Study of Women's Health Across the Nation were used to construct a 10‐year average Healthy Lifestyle Score (HLS) during the midlife. Markers of subclinical atherosclerosis were measured 14 years after baseline and included common carotid artery intima‐media thickness (CCA‐IMT), adventitial diameter (CCA‐AD), and carotid plaque. The associations of average HLS with CCA‐IMT and CCA‐AD were estimated using linear models; the association of average HLS with carotid plaque was estimated using cumulative logit models. Average HLS was associated with smaller CCA‐IMT and CCA‐AD in the fully adjusted models (P=0.0031 and <0.001, respectively). Compared with participants in the lowest HLS level, those in the highest level had 0.024 mm smaller CCA‐IMT (95% confidence interval: −0.048, 0.000), which equals 17% of the SD of CCA‐IMT, and 0.16 mm smaller CCA‐AD (95% confidence interval: −0.27, −0.04), which equals 24% of the SD of CCA‐AD. Among the 3 components of the HLS, abstinence from smoking had the strongest association with subclinical atherosclerosis.

Conclusions

Healthy lifestyle during the menopausal transition is associated with less subclinical atherosclerosis, highlighting the growing recognition that the midlife is a critical window for cardiovascular prevention in women.

Contraceptive preferences and unmet need for contraception in midlife women: where are the data?

This commentary discusses the limited availability of information on contraceptive preferences and unmet need for contraception among midlife women in both high and low income countries. Given that risk of pregnancy continues until women reach menopause and given the increased risk of pregnancy complications, elective abortion, and maternal mortality in women aged 45 to 54 years old, increased focus on gathering basic data on midlife women's preferences and unmet need is warranted.

The relationship between coping, health competence and patient participation among patients with inactive inflammatory bowel disease

BACKGROUND

Coping is an integral part of adjustment for patients with Inflammatory Bowel Disease but has not been well described in the literature. This study explored the relationship between coping, perceived health competence, patient preference for involvement in their treatment, depression and quality of life, particularly among patients with inactive disease (in remission).

METHODS

Subjects (n=70) with active and inactive IBD completed questionnaires, including the Inflammatory Bowel Disease Quality of Life Questionnaire, Beck Depression Inventory, Perceived Health Competence Scale and the Coping Inventory for Stressful Situations. The Harvey Bradshaw Index measured disease activity.

RESULTS

Patients with inactive IBD demonstrated significantly more interest in participating in their treatment (p<.05), more perceived health competence (p=.001), less depressive symptoms (p<.001), more task oriented coping (p=.02), and better quality of life than those with active disease. Only Task Oriented Coping was significantly negatively associated with the number of flares among inactive patients (p<.001). Patient preference for participation in treatment was inversely associated with Avoidance (p=.005), Distraction (p=.008), and Social Diversion (p=.008) coping among inactive patients.

CONCLUSION

Among patients in remission, those who expressed a greater interest in treatment participation were also less likely to practice maladaptive coping. Our data demonstrate that a more active coping style may be associated with improved health outcome. Compared to patients with active disease, patients in remission are more likely to employ task oriented coping, demonstrate a higher interest in treatment participation, report greater perceived control of their health, and exhibit less depression symptoms. Our findings may increase awareness of the importance of identifying coping strategies for IBD patients, including those in remission.

Abstract P4-15-12: Rebastinib in combination with eribulin ablates TIE2-expressing macrophages, reduces metastasis, and increases survival in the PyMT metastatic breast cancer model

In cancer models, TIE2 kinase plays an important role in angiogenesis, vasculogenesis, and tumor metastasis. TIE2 expression is largely restricted to vascular endothelial cells, tissue macrophages, and bone marrow derived TIE2-expressing monocytes (TEMs), which are proangiogenic, provasculogenic and enhance invasiveness. The hypoxic tumor environment engendered by damaging the vasculature with chemotherapy, radiation, or anti-angiogenic treatments leads to rebound tumor vascularization by an angiogenic switch from the VEGF pathway to the angiopoietin/TIE2 pathway. This leads to recruitment of provasculogenic TEMs from the bone marrow, leading to the growth of residual tumor cells and disease progression. Significantly, a subset of TIE2-expressing macrophages are located within specialized vascular structures known as tumor microenvironment for metastases (TMEMs). Recent observations have linked TIE2-expressing macrophages within TMEM structures to intravasation of cancer cells into circulation and subsequent dissemination to metastatic sites. We hypothesized that TIE2 inhibition should decrease migration and association of TEMs with blood vessels in the tumor stroma, therefore blocking their proangiogenic activity and leading to reduced tumor growth. TIE2 inhibition may also alter TMEM function, leading directly to a blockade of metastasis.

Rebastinib is a picomolar inhibitor of TIE2 kinase, and exhibits an extraordinarily long off-rate from TIE2, measured to be over 24 hours in a cell-based assay. Herein, we examine the efficacy of rebastinib in the polyoma middle-T antigen (PyMT) syngeneic mouse breast cancer model. In this model, PyMT breast cancer cells are implanted in the mammary fat pad, and primary tumor growth leads to metastasis, which is known to be modulated by TEMs and TMEM vascular structures. We examined dosing rebastinib in combination with eribulin, an inhibitor of microtubule dynamics that recently was FDA-approved for treatment-refractory metastatic breast cancer. Rebastinib treatment in this model significantly ablated TEMs in the primary tumor stroma and caused a significant decrease in lung metastases. Furthermore, the combination of rebastinib and eribulin led to a significant further decrease in lung metastases compared to treatment with eribulin alone (Table 1). Rebastinib also enhanced the activity of eribulin in reducing primary tumor growth and regrowth of tumor post-resection.

TIE2 inhibition represents a novel treatment approach for metastatic breast cancer and other cancers that rely on TEMs and TMEMs for growth and metastasis. As such, rebastinib has been selected for further clinical development in combination with eribulin for treatment-refractory metastatic breast cancer, with a Phase 1b trial being planned for late 2013.

Rebastinib reduces lung metastases in the PyMT breast cancer modelTreatmentLung Metastases (% of Control)Vehicle100%Eribulin 1 mg/kg three times/week71%Rebastinib 10 mg/kg twice/week + Eribulin 1 mg/kg23%Eribulin 0.3 mg/kg three times/week71%Rebastinib 10 mg/kg twice/week + Eribulin 0.3 mg/kg51%Eribulin 0.1 mg/kg three times/week72%Rebastinib 10 mg/kg twice/week + Eribulin 0.1 mg/kg43%

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-15-12.

Abstract P4-15-13: Rebastinib in combination with paclitaxel ablates TIE2-expressing macrophages, reduces metastasis, and increases survival in the PyMT metastatic breast cancer model

In cancer models, TIE2 kinase plays an important role in angiogenesis, vasculogenesis, and tumor metastasis. TIE2 expression is largely restricted to vascular endothelial cells, tissue macrophages, and bone marrow derived TIE2-expressing monocytes (TEMs), which are proangiogenic, provasculogenic and enhance invasiveness. The hypoxic tumor environment engendered by damaging the vasculature with chemotherapy, radiation, or anti-angiogenic treatments leads to rebound tumor vascularization by an angiogenic switch from the VEGF pathway to the angiopoietin/TIE2 pathway. This leads to recruitment of provasculogenic TEMs from the bone marrow, leading to the growth of residual tumor cells and disease progression. Significantly, a subset of TIE2-expressing macrophages are located within specialized vascular structures known as tumor microenvironment for metastases (TMEMs). Recent observations have linked TIE2-expressing macrophages within TMEM structures to intravasation of cancer cells into circulation and subsequent dissemination to metastatic sites. We hypothesized that TIE2 inhibition should decrease migration and association of TEMs with blood vessels in the tumor stroma, therefore blocking their proangiogenic activity and leading to reduced tumor growth. TIE2 inhibition may also alter TMEM function, leading directly to a blockade of metastasis.

Rebastinib is a picomolar inhibitor of TIE2 kinase, and exhibits an extraordinarily long off-rate from TIE2, measured to be over 24 hours in a cell-based assay. Herein, we examine the efficacy of rebastinib in the polyoma middle-T antigen (PyMT) syngeneic mouse breast cancer model. In this model, PyMT breast cancer cells are implanted in the mammary fat pad, and primary tumor growth leads to metastasis, which is known to be modulated by TEMs and TMEM vascular structures. We examined multiple dosing schedules of rebastinib in combination with paclitaxel. Rebastinib treatment in this model significantly ablated TEMs in the primary tumor stroma and caused a significant decrease in lung metastases (Table 1). Furthermore, the combination of rebastinib and paclitaxel led to a significant further decrease in lung metastases compared to treatment with paclitaxel or rebastinib alone. Rebastinib also enhanced the activity of paclitaxel in reducing primary tumor growth and regrowth of tumor post-resection.

TIE2 inhibition with targeted therapy represents a novel treatment approach for metastatic breast cancer and other cancers that rely on TEMs and TMEMs for growth and metastasis. As such, rebastinib has been selected for further clinical development for treatment-refractory metastatic breast cancer, with a Phase 1b trial being planned for late 2013.

Rebastinib reduces lung metastases in the PyMT breast cancer modelStudynTreatmentLung Metastases (% of Control)110Vehicle100%110Paclitaxel 10 mg/kg Q5D36%110Rebastinib 10 mg/kg BID28%110Rebastinib 10 mg/kg BID + Paclitaxel7%210Vehicle100%210Paclitaxel 10 mg/kg Q5D51%210Rebastinib 10 mg/kg QD + Paclitaxel21%33Vehicle100%33Paclitaxel 10 mg/kg Q5D58%33Rebastinib 10 mg/kg twice/week + Paclitaxel28%

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-15-13.

Selective shunt in the management of variceal bleeding in the era of liver transplantation

This study reports the Emory experience with 147 distal splenorenal shunts (DSRS) and 110 orthotopic liver transplants (OLT) between January 1987 and December 1991. The purpose was to clarify which patients with variceal bleeding should be treated by DSRS versus OLT. Distal splenorenal shunts were selected for patients with adequate or good liver function. Orthotopic liver transplant was offered to patients with end-stage liver disease who fulfilled other selection criteria. The DSRS group comprised 71 Child's A, 70 Child's B, and 6 Child's C patients. The mean galactose elimination capacity for all DSRS patients was 330 +/- 98 mg/minute, which was significantly (p less than 0.01) above the galactose elimination capacity of 237 +/- 82 mg/minute in the OLT group. Survival analysis for the DSRS group showed 91% 1-year and 77% 3-year survival, which was better than the 74% 1-year and 60% 3-year survivals in the OLT group. Variceal bleeding as a major component of end-stage disease leading to OLT had significantly (p less than 0.05) poorer survival (50%) at 1 year compared with patients without variceal bleeding (80%). Hepatic function was maintained after DSRS, as measured by serum albumin and prothrombin time, but galactose elimination capacity decreased significantly (p less than 0.05) to 298 +/- 97 mg/minute. Quality of life, measured by a self-assessment questionnaire, was not significantly different in the DSRS and OLT groups. Hospital charges were significantly higher for OLT (median, $113,733) compared with DSRS ($32,674). These data support a role for selective shunt in the management of patients with variceal bleeding who require surgery and have good hepatic function. Transplantation should be reserved for patients with end-stage liver disease. A thorough evaluation, including tests of liver function, help in selection of the most appropriate therapeutic approach.