Abstract PD03-05: Analysis of tumour cell signaling in response to neoadjuvant metformin in women with early stage breast cancer

Background: The anti-diabetic drug metformin, commonly used to treat type 2 diabetes due to its ability to reduce circulating glucose and insulin, has emerged as a potential anti-cancer agent. Observational studies have reported decreased cancer incidence and mortality in diabetics receiving metformin. Metformin's ability to reduce insulin may be particularly important for breast cancer (BC) because hyperinsulinemia is an adverse prognostic factor and most cells express the insulin receptor (IR). The anti-cancer effects of metformin are associated with both direct (insulin-independent) and indirect (insulin-dependent) actions. Direct effects are linked to activation of AMPK and an inhibition of mTOR signalling, while indirect effects are mediated by reductions in circulating insulin levels, leading to reduced IR-activated PI3K signalling. We conducted a neoadjuvant, single arm, “window of opportunity” trial examining the clinical and biological effects of metformin on thirty-nine locoregional BC patients awaiting definitive surgery.

Methods: Non-diabetic women with newly diagnosed, untreated BC were given metformin 500 mg tid for ≥2 weeks post diagnostic core biopsy until surgery. Fasting blood and tumour samples were collected at diagnosis and surgery. Blood glucose and insulin were assayed to assess the physiologic effects of metformin, while IHC analysis of tumours was used to characterize cellular markers before and after metformin. Specifically, IR levels and the phosphorylation status of proteins involved in AMPK and PI3K/AKT/mTOR signalling, including AMPK (T172) and AKT (S473), were examined.

Results: 39 patients with a mean age of 51 years received metformin for a median of 18 days (range 13–40) with minor GI toxicities. The clinical effects (previously reported) included significant (p < 0.05) decreases in body mass index (−0.5 kg/m2), weight (−1.2 kg), glucose (−0.14 mM) and HOMA (an estimate of insulin resistance, −0.21), and a decrease in insulin (−4.7 pmol/L) that approached significance (p = 0.0686). Ki67 staining in tumour tissue decreased significantly and TUNEL increased significantly. Levels of IR expression decreased significantly (from 4.39 to 3.82, p = 0.0375) as did the phosphorylation status of AKT (S473) and AMPK (T172) (from 9.82 to 7.08, p = <0.0001; from 6.2 to 5.1, p = 0.0034, respectively).

Conclusions: Metformin impact was consistent with beneficial anti-cancer effects. Reduced AKT phosphorylation, coupled with decreased insulin and IR levels, suggest insulin-dependent effects are important in the clinical setting. Assessment of additional factors in BC cells, including OCT1 expression (required for metformin uptake), and the phosphorylation of ACC (a marker of AMPK activation), is underway and will be reported. Integrated analysis of these factors combined with the physiological and molecular data described above will further enhance understanding of metformin action in the clinical setting.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD03-05.

PD04-09: Self-Reported Cognitive Attributes and Fatigue Improve over Long-Term Follow-Up in Breast Cancer Survivors; Some Cognitive Attributes Are Worse in Breast Cancer Survivors Than in Non-Cancer Controls

Background: Cognitive deficits and fatigue have been reported in breast cancer (BC) patients undergoing a variety of treatments, including chemotherapy; in some studies these concerns persist after completion of treatment. We examined these factors over time (median 11 yrs) in a longitudinal study of BC patients and compared the status of long-term BC survivors to non-BC controls.

Methods: 535 T1-3, N0-1, M0 BC patients were enrolled 1989–96; 260 women survived without metastases to participate in long-term follow-up (LTFU) measurements in 2006–8. 161 controls without BC were enrolled 2007–8. Questionnaires examined a range of QOL attributes; here we focus on items related to cognition and fatigue including: EORTC QLQ C30 (cognitive functioning, fatigue), Profile of Mood States (POMS — confusion/bewilderment, fatigue/inertia, vigor/activity), Fatigue Symptom Inventory (FSI — average fatigue past week, total disruption index), Everyday Problems (EDP — forgetfulness, difficulty concentrating, easily distracted). 166 of the BC patients had also completed EORTC and POMS at diagnosis and 1 year, and change in items on these questionnaires was calculated. Age and income adjusted differences between BC (LTFU) and controls were analyzed. Clinical significance was defined as ≥5% of the scale range or an effect size of ≥0.2 and statistical significance as P≤ 0.05.

Results: BC cases were older than controls (62.3 vs 59.1 yr), had lower education (24.6 vs 10.2% high school only) and family income (38.2 vs 19.8% < $60,000 annually) (all P<0.01). Cognitive attributes: BC patients showed clinically and statistically significant improvements between diagnosis and LTFU on POMS confusion/bewilderment but not EORTC cognitive functioning. Comparing BC (LTFU) to controls, in multivariate analyses adjusted for age and income, EORTC cognitive functioning (81.5 vs 87.4) and EDP forgetfulness (0.9 vs 0.6) were clinically and statistically significantly worse in BC patients than controls. In contrast, POMS confusion/bewilderment, EDP difficulty concentrating and EDP easily distracted scores were similar in BC patients at LTFU and controls. Fatigue: BC patients showed clinically and statistically significant improvements between diagnosis and LTFU on EORTC fatigue, POMS fatigue/inertia and POMS vigor/activity. After adjustment for age and income there were no clinically and statistically significant differences between BC (LTFU) and controls on any fatigue items.

Conclusions: Fatigue items, as well as some cognitive items, improved over time in BC patients and scores were comparable to scores in non-BC controls at LTFU. However, scores on some cognitive items were worse in LTFU BC patients than in non-BC controls raising concerns that BC diagnosis and treatment may be associated with long-term adverse effects on some aspects of self-reported cognitive attributes.

(Funded by The Breast Cancer Research Foundation)

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr PD04-09.

Unleash innovation in foreign subsidiaries

In multinational corporations, growth-triggering innovation often emerges in foreign subsidiaries from employees closest to customers and least attached to the procedures and politeness of the home office. But too often, heavy-handed responses from headquarters squelch local enthusiasm and drive out good ideas--and good people. The authors' research into more than 50 multinationals suggests that encouraging innovation in foreign subsidiaries requires a change in attitude. Companies should start to think of foreign subsidiaries as peninsulas rather than as islands--as extensions of the company's strategic domain rather than as isolated outposts. If they do, innovative ideas will flow more freely from the periphery to the corporate center. Basing their arguments on a rich array of examples, the authors say that encouraging such "innovation at the edges" also requires a new set of practices, with two aims: to improve the formal and informal channels of communication between headquarters and subsidiaries and to give foreign subsidiaries more authority to see their ideas through. The challenge for executives of multinationals is to find ways to liberalize, not tighten, internal systems and to delegate more authority to local subsidiaries. It isn't enough to ask subsidiary managers to be innovative; corporate managers need to give them incentives and support systems to facilitate their efforts. The authors suggest four approaches: give seed money to subsidiaries; use formal requests for proposals as a way of increasing the demand for seed money; encourage subsidiaries to be incubators for fledgling businesses; and build international networks. As part of the last approach, multinationals also need to create roles for idea brokers who can link entrepreneurs in foreign subsidiaries with other parts of the company.

Risk of menopause during the first year after breast cancer diagnosis

PURPOSE

Premenopausal women with breast cancer often enter a premature menopause during initial treatment of their malignancy, with resulting loss of childbearing capacity, onset of menopausal symptoms, and subsequent prolonged exposure to long-term risks of menopause. Adjuvant therapy is believed to contribute to this early menopause.

PATIENTS AND METHODS

One hundred eighty-three premenopausal women with locoregional breast cancer (tumor-node-metastasis staging system classification, T1-3 N0-1 M0) who had undergone surgical treatment and provided information on menopausal status at diagnosis and 1 year later were enrolled. Systemic adjuvant therapy was recorded. Univariate and multivariate predictors of menopause were examined.

RESULTS

Age, weight gain, tumor stage, nodal stage, and systemic adjuvant therapy (chemotherapy, tamoxifen) were all significant univariate correlates of menopause. In multivariate analysis, age, chemotherapy, and hormone therapy (tamoxifen) made significant independent contributions to the onset of menopause.

CONCLUSION

Age and systemic chemotherapy are the strongest predictors of menopause in women with locoregional breast cancer. They independently contribute to menopause. A graphic representation of our multivariate model allows an estimation of risk of menopause according to patient age and planned adjuvant treatment, and it may facilitate clinical decision-making.

Adjuvant treatment and onset of menopause predict weight gain after breast cancer diagnosis

PURPOSE

Weight gain is common during the first year after breast cancer diagnosis. In this study, we examined clinical factors associated with body size at diagnosis and weight gain during the subsequent year.

PATIENTS AND METHODS

An inception cohort of 535 women with newly diagnosed locoregional breast cancer underwent anthropometric measurements at baseline and 1 year. Information was collected on tumor- and treatment-related variables, as well as diet and physical activity.

RESULTS

Mean age was 50.3 years; 57% of women were premenopausal. Mean baseline body mass index (weight [kg] divided by height [m] squared) was 25.5 kg/m2. Overall, 84.1% of the patients gained weight. Mean weight gain was 1.6 kg (95% confidence interval, 1.2 to 1.9 kg), 2.5 kg (95% confidence interval, 1.8 to 3.2 kg) in those receiving chemotherapy, 1.3 kg (95% confidence interval, 0.7 to 1.8 kg) in those receiving tamoxifen only, and 0.6 kg (95% confidence interval, 0.01 to 1.3 kg) in those receiving no adjuvant treatment. Menopausal status at diagnosis (P = .02), change in menopausal status over the subsequent year (P = .002), axillary nodal status (P = .009), and adjuvant treatment (P = .0002) predicted weight gain in univariate analysis. In multivariate analysis, onset of menopause and administration of chemotherapy were independent predictors of weight gain (all P < or = .05). Caloric intake decreased (P < .01) and physical activity increased (P < .05) during the year after diagnosis; these factors did not explain the observed weight gain.

CONCLUSION

Weight gain is common after breast cancer diagnosis; use of adjuvant chemotherapy and onset of menopause are the strongest clinical predictors of this weight gain.

Young children's adjustment to chronic family adversity: a longitudinal study of low-income families

OBJECTIVE

To test the relation between multiple family stressors and young children's adjustment problems.

METHOD

Longitudinal data were collected on 300 low-income, ethnically diverse, male subjects beginning during infancy and followed until age 31/2.

RESULTS

General support was found for the family stressor hypothesis. Stressor groups at 18 and 24 months predicted Child Behavior Checklist Externalizing and Internalizing factors at 24 and 42 months, including clinically elevated problems.

CONCLUSIONS

The results confirm and extend previous investigation of the family stressor hypothesis. They suggest that psychological evaluations of young children need to be ecologically based, including intra- and extrafamilial factors that appear to cumulatively increase risk of behavior problems.

Lowering the cut off value of an automated chlamydia enzyme immunoassay and confirmation by PCR and direct immunofluorescent antibody test

AIMS

To increase the sensitivity of an automated chlamydia enzyme immunoassay by significantly lowering its cut off value, and to maintain specificity by confirmation with polymerase chain reaction (PCR) and direct immunofluorescent antibody test (DFA).

METHODS

Over five months, the cut off value of the enzyme immunoassay used to screen urogenital samples for chlamydia antigen was reduced from 80 to 10. Samples with a test value of 10 or above were further tested with a commercial PCR assay. All samples during the first three months and discrepant samples during the last two months of the study were also tested with the DFA.

RESULTS

3250 urogenital swabs (1246 urethral, 1335 endocervical, 669 pooled urethral/endocervical) from 1246 males and 2004 females were processed. Using the manufacturer's recommended cut off of 80, the enzyme immunoassay identified chlamydia antigen in 134 samples (4.1%). Using the lower cut off value of 10 and either PCR or DFA as the confirmatory test, Chlamydia trachomatis was identified in 178 samples (5.5%). Thus, 45 additional positive samples were identified and the confirmed detection rate was increased by 33.8% (45/133). Excluding equivocal PCR results, the concordance between DFA and PCR was 91.8%. This strategy increased the detection rate by 2.1% in men and 0.9% in women (significant only in men). In female patients, pooled urethral/endocervical swabs as a specimen gave a significantly higher yield than endocervical swabs regardless of whether the lower cut off strategy was used.

CONCLUSIONS

This strategy of significantly lowering the cut off test value with confirmation on the same specimen by either PCR or DFA is feasible and cost effective. The use of pooled urethral/ endocervical specimens in females should be considered routinely as detection rate was significantly improved.

Elevated levels of plasma triglycerides are associated with histologically defined premenopausal breast cancer risk

Lipids and lipoproteins have been associated with breast cancer risk; however, published results have been inconsistent. To clarify these associations, we measured fasting lipids in women undergoing breast biopsies. A case-control study examined the association of fasting levels of lipids with histologically defined breast cancer risk. Four groups of premenopausal women were assembled on the basis of histological appearance of breast tissue: 1) no epithelial proliferation (n = 102), 2) proliferation without atypia (n = 53), 3) atypical hyperplasia or carcinoma in situ (n = 53), and 4) node-negative invasive cancer (n = 102). A postoperative fasting blood specimen was analyzed for cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. Demographics, risk factors, diet, physical activity, fasting weight, and skin-fold thickness were measured. Triglyceride levels were significantly higher in women with node-negative invasive cancer (0.94 +/- 1.04 mg/ml) than in those with no epithelial proliferation (0.83 +/- 1.04 mg/ml, p = 0.03). This association persisted after adjustment for age, body size, lipids, reproductive and familial risk factors, and previous benign breast problems (p < 0.01), in keeping with an independent association of elevated triglycerides with breast cancer risk.

Cyclical mastopathy and premenopausal breast cancer risk. Results of a case-control study

Cyclical mastopathy (CM) is a common clinical syndrome of premenstrual breast swelling and tenderness. Its symptoms are relieved by reduction in dietary fat intake and, because fat intake may be associated with breast cancer risk, it was hypothesized that CM may also be related to breast cancer risk. This case-control study included 192 premenopausal women with a recent history of axillary node-negative breast cancer and 192 age-matched premenopausal controls. Subjects provided information on diet and risk factors, and they recorded breast symptoms prospectively during one menstrual cycle. Symptoms in the noncancerous breast of cases and the matched (right or left) breast of controls were examined. A cyclical pattern of symptoms was identified in both groups; breast tenderness scores were similar postmenstrually (p = 0.31) but were significantly higher premenstrually in the case group (p = 0.03). Cases also had a greater premenstrual increase in breast tenderness than controls (p = 0.03). When the effects of other risk factors for breast cancer were included in multivariate analyses, the association of cyclical tenderness with breast cancer persisted (p = 0.05), the odds ratio for severe tenderness being 3.32. Thus, we have identified an association of cyclical breast tenderness with breast cancer risk in premenopausal women. The association persists after consideration of diet and the effects of other breast cancer risk factors.

Placental transfer of tetanus toxoid antibodies in Nigerian mothers

The aim of this study was to assess the efficacy of the tetanus toxoid immunization programme in Nigeria, specifically the placental transfer of antibody to newborn Nigerian babies. Tetanus toxoid antibody levels were measured in 39 mother-baby pairs in Ibadan, Nigeria and compared with 78 British mother-baby pairs. Geometric means of the ratios of cord/mother (sequestration index SI) were 0.776 for Nigerian pairs and 1.306 for British pairs, indicating a limitation in the placental transfer of tetanus toxoid in the Nigerian population. These findings confirm that there is a block in the placental transfer of anti-tetanus toxoid antibodies in African populations which will affect current immunization programmes and requires further investigation.