Debora Macis

Efficacy of tamoxifen based on cytochrome P450 2D6, CYP2C19 and SULT1A1 genotype in the Italian Tamoxifen Prevention Trial

The role of pharmacogenomics and tamoxifen was investigated by analyzing several polymorphisms of cytochrome P450 and SULT1A1 gene in a nested case control study from the Italian Tamoxifen Prevention Trial. This study included 182 Caucasian subjects, 47 breast cancer (BC) cases and 135 matched controls. We used the AmpliChip CYP450 Test to screen 33 alleles of CYP2D6 and 3 of CYP2C19. One more variant for CYP2C19*17 and two single-nucleotide polymorphisms for the gene SULT1A1 were also performed. By using the AmpliChip CYP450 Test, out of 182 subjects, we identified 8 poor metabolizer (PM), 17 intermediate metabolizer (IM), 151 extensive metabolizer (EM) and 3 ultrarapid metabolizer (UM). PM women allocated to the tamoxifen arm showed a higher risk of developing BC compared to the remaining phenotypes (P=0.035). In an exploratory analysis, among 58 women with a CYP2D6*2A allele, 9 BCs were diagnosed in the placebo arm and only 1 in the tamoxifen arm (P=0.0001). CYP2C19 and SULT1A1 polymorphisms did not show any correlation with tamoxifen efficacy. Tamoxifen showed reduced efficacy in CYP2D6 PMs in the chemoprevention setting. Conversely, the CYP2D6*2A allele may be associated with increased efficacy of tamoxifen. These findings support the relevance of pharmaco-genomics in tailoring tamoxifen treatment.

Randomized Dose-Ranging Trial of Tamoxifen at Low Doses in Hormone Replacement Therapy Users

PURPOSE The combination of hormone replacement therapy (HRT) and low-dose tamoxifen may retain the benefits while reducing the risks of either agent. We assessed the optimal biologic dose and schedule of tamoxifen in HRT users using surrogate end point biomarkers and menopausal symptoms. SUBJECTS AND METHODS Two hundred ten current or de novo HRT users were randomly assigned to one of the following four arms: tamoxifen 1 mg/day and placebo/week, placebo/day and tamoxifen 10 mg/week, tamoxifen 5 mg/day and placebo/week, or both placebos for 12 months. The primary end point was the change of plasma insulinlike growth factor 1 (IGF-I) through 12 months, and secondary end points were IGF-I/IGF binding protein-3 (IGFBP-3) ratio, fibrinogen, antithrombin III, C reactive protein, C-telopeptide, mammographic percent density, and endometrial thickness. Endometrial proliferation was assessed by Pipelle biopsy in superficial, deep glandular, and stromal compartments after 12 months. RESULTS Compared with placebo, IGF-I declined in all tamoxifen arms (P = .005), with a greater change on 5 mg/day (P = .019 v 10 mg/week or 1 mg/day). Tamoxifen increased IGFBP-3 and lowered antithrombin-III, C reactive protein, and mammographic density, with greater effects of 5 mg/day. Tamoxifen increased endometrial thickness but not Ki-67 expression, which was lower on 5 mg/day among the three doses. Menopausal symptoms were not significantly worsened by tamoxifen. CONCLUSION Doses of tamoxifen < or = 5 mg/day modulate favorably biomarkers of breast carcinogenesis and cardiovascular risk in HRT users with no increase of endometrial proliferation and menopausal symptoms. A dose of 5 mg/day was the most effective and has been selected for a phase III trial in HRT users.

Prognostic Effect of Circulating Adiponectin in a Randomized 2 × 2 Trial of Low-Dose Tamoxifen and Fenretinide in Premenopausal Women at Risk for Breast Cancer

PURPOSE Adipokines are linked to obesity and insulin sensitivity and have recently been related to breast cancer risk and prognosis. We investigated the associations of plasma leptin and adiponectin with mammographic density and disease status and assessed their prognostic effect on recurrence-free survival in premenopausal women at risk for breast cancer. PATIENTS AND METHODS We measured circulating lipids, insulin-like growth factor 1, glucose, insulin and insulin sensitivity (calculated by homeostasis model assessment [HOMA] index), leptin, adiponectin, and leptin-to-adiponectin ratio in 235 premenopausal women with pT1mic/pT1a breast cancer (n = 21), intraepithelial neoplasia (n = 160), or 5-year Gail risk of 1.3% or greater (n = 54) who participated in a 2 × 2 trial of low-dose tamoxifen, fenretinide, both agents, or placebo over a 2-year period. RESULTS At baseline, adiponectin levels were directly associated with mammographic density and HDL cholesterol and negatively associated with leptin, leptin-to-adiponectin ratio, body mass index (BMI), and HOMA index. Median adiponectin levels were lower in affected than in unaffected women (P = .006). After a median of 7.2 years and total of 57 breast neoplastic events, there was a 12% reduction in the risk of breast neoplastic events per unit increase of adiponectin (adjusted hazard ratio, 0.88; 95% CI, 0.81 to 0.96; P = .03). There was no interaction between treatment and adiponectin levels. CONCLUSION Low adiponectin levels are associated with a history of prior intraepithelial neoplasia or pT1mic/pT1a breast cancer and higher risk of second breast neoplastic events in premenopausal women. The associations are independent of BMI, mammographic density, and treatment. Our findings support the role of adiponectin as a potential target for premenopausal breast cancer prevention and treatment.

Factors associated with circulating levels of insulin-like growth factor-I and insulin-like growth factor binding protein-3 in 740 women at risk for breast cancer

Prospective studies have shown an association between elevated plasma levels of insulin-like growth factor-I (IGF-I) and/or decreased levels of its major circulating carrier protein insulin-like growth factor binding protein-3 (IGFBP-3) and increased risk of major cancers. Identifying the factors which affect these biomarkers is of particular interest as subjects at increased risk could benefit from lifestyle changes, and/or chemoprevention intervention. We evaluated the association between constitutional, hormonal and clinical factors and IGF-I and IGFBP-3 in 740 women, including 376 unaffected women and 364 women with intraepithelial neoplasia (IEN) or early invasive breast cancer enrolled in breast cancer chemoprevention trials, conducted at a single institution. Age, body mass index (BMI), height, waist to hip girth ratio (WHR), parity, menopausal status, age at menarche, number of affected first degree relatives, number of biopsies and breast cancer status were considered in the analysis. Women with early breast cancer had 21% higher IGF-I levels ( p=0.033) and 19% higher IGF-I/IGFBP-3 molar ratio ( p=0.047) than unaffected women. In unaffected women, age was negatively associated with IGF-I ( p=0.002) and IGF-I/IGFBP-3 ( p=0.001), while age at menarche was negatively associated with IGFBP-3 levels ( p=0.043). In women with IEN or early breast cancer, IGF-I levels were negatively associated with age ( p < 0.001), and positively associated with prior biopsies for benign disease ( p=0.013), while age, parity and menopausal status were significant predictors of IGF-I/IGFBP-3 molar ratio. We conclude that circulating IGF-I levels are higher in women with prior breast cancer compared to unaffected women, and that IGF-I and/or IGFBP-3 levels are influenced by age and by reproductive and hormonal factors. These findings support their putative role as breast cancer risk biomarker.

Randomized Biomarker Trial of Anastrozole or Low-Dose Tamoxifen or Their Combination in Subjects with Breast Intraepithelial Neoplasia

Purpose: In the Anastrozole, Tamoxifen Alone or in Combination trial, the combination arm was inferior to anastrozole alone in terms of disease-free survival possibly due to an adverse pharmacokinetic interaction or a predominant estrogenic effect of tamoxifen under estrogen deprivation. We assessed whether the addition of a lower dose of tamoxifen influenced anastrozole bioavailability and favorably modulated biomarkers of bone fracture, breast cancer, cardiovascular disease, and endometrial cancer risk. The influence of CYP2D6 genotype on tamoxifen effects was also determined. Experimental Design: Seventy-five postmenopausal women with breast intraepithelial neoplasia were randomly allocated to either 1 mg/d anastrozole or 10 mg/wk tamoxifen or their combination for 12 months. Study endpoints were plasma drug concentrations and changes of C-telopeptide, osteocalcin, estradiol/sex hormone binding globulin (SHBG) ratio, estrone sulfate, insulin-like growth factor-I (IGF-I)/insulin-like growth factor binding protein-3 (IGFBP-3), C-reactive protein, antithrombin-III, endometrial Ki-67 expression, and thickness. Results: Anastrozole concentrations were not affected by the combination with low-dose tamoxifen, whereas endoxifen levels were lower in poor CYP2D6 metabolizers. C-telopeptide increased by 20 with anastrozole and decreased by 16 with tamoxifen and by 7 with their combination (P < 0.001); osteocalcin showed similar changes. Compared with anastrozole, the combination arm showed lower IGF-I/IGFBP-3 levels (17 versus 9; P = 0.004) and lower estradiol/SHBG and estrone sulfate reductions (15 versus 29 and 30 versus 38, respectively). However, IGF-I/IGFBP-3 and estradiol/SHBG did not decrease in poor CYP2D6 metabolizers. Endometrial thickness was not greater in the combination than in the anastrozole arm. Conclusions: The addition of a weekly tamoxifen administration did not impair anastrozole bioavailability and modulated favorably its safety profile, providing the rationale for further studies. (Clin Cancer Res 2009;15(22):705360)

A randomized phase II presurgical trial of weekly low-dose tamoxifen versus raloxifene versus placebo in premenopausal women with estrogen receptor-positive breast cancer

IntroductionWe previously demonstrated that 1 or 5 mg per day of tamoxifen (T) given for four weeks before surgery reduces Ki-67 in breast cancer (BC) patients to the same extent as the standard 20 mg/d. Given the long half-life of T, a weekly dose (10 mg per week (w)) may be worth testing. Also, raloxifene (R) has shown Ki-67 reduction in postmenopausal patients in a preoperative setting, but data in premenopausal women are limited. We conducted a randomized trial testing T 10 mg/w vs. R 60 mg/d vs. placebo in a presurgical model.MethodsOut of 204 screened subjects, 57 were not eligible, 22 refused to participate and 125 were included in the study. The participants were all premenopausal women with estrogen receptor-positive BC. They were randomly assigned to either T 10mg/w or R 60 mg/d or placebo for six weeks before surgery. The primary endpoint was tissue change of Ki-67. Secondary endpoints were modulation of estrogen and progesterone receptors and several other circulating biomarkers.ResultsKi-67 was not significantly modulated by either treatment. In contrast, both selective estrogen receptor modulators (SERMs) significantly modulated circulating IGF-I/IGFBP-3 ratio, cholesterol, fibrinogen and antithrombin III. Estradiol was increased with both SERMs. Within the tamoxifen arm, CYP2D6 polymorphism analysis showed a higher concentration of N-desTamoxifen, one of the tamoxifen metabolites, in subjects with reduced CYP2D6 activity. Moreover, a reduction of Ki-67 and a marked increase of sex hormone-binding globulin (SHBG) were observed in the active phenotype.ConclusionsA weekly dose of tamoxifen and a standard dose of raloxifene did not inhibit tumor cell proliferation, measured as Ki-67 expression, in premenopausal BC patients. However, in the tamoxifen arm women with an extensive phenotype for CYP2D6 reached a significant Ki-67 modulation.

A presurgical study of lecithin formulation of green tea extract in women with early breast cancer

Epidemiologic data support an inverse association between green tea intake and breast cancer risk. Greenselect Phytosome (GSP) is a lecithin formulation of a caffeine-free green tea catechin extract. The purpose of the study was to determine the tissue distribution of epigallocatechin-3-O-gallate (EGCG) and its effect on cell proliferation and circulating biomarkers in breast cancer patients. Twelve early breast cancer patients received GSP 300 mg, equivalent to 44.9 mg of EGCG, daily for 4 weeks prior to surgery. The EGCG levels were measured before (free) and after (total) enzymatic hydrolysis by HPLC-MS/MS in plasma, urine, breast cancer tissue, and surrounding normal breast tissue. Fasting blood samples were taken at baseline, before the last administration, and 2 hours later. Repeated administration of GSP achieved levels of total EGCG ranging from 17 to 121 ng/mL in plasma. Despite a high between-subject variability, total EGCG was detectable in all tumor tissue samples collected up to 8 ng/g. Median total EGCG concentration was higher in the tumor as compared with the adjacent normal tissue (3.18 ng/g vs. 0 ng/g, P = 0.02). Free EGCG concentrations ranged from 8 to 65.8 ng/mL in plasma (P between last administration and 2 hours after <0.001). Free EGCG plasma levels showed a significant positive correlation with the Ki-67 decrease in tumor tissue (P = 0.02). No change in any other biomarkers was noted, except for a slight increase in testosterone levels after treatment. Oral GSP increases bioavailability of EGCG, which is detectable in breast tumor tissue and is associated with antiproliferative effects on breast cancer tissue. Cancer Prev Res; 10(6); 363–9. ©2017 AACR.

A randomized, placebo-controlled, phase II, presurgical biomarker trial of celecoxib versus exemestane in postmenopausal breast cancer patients

In breast cancer presurgical trials, the Ki-67 labeling index predicts disease outcome and offers clues to the preventive potential of drugs. We conducted a placebo-controlled trial to evaluate the activity of exemestane and celecoxib before surgery. The main endpoint was the change in Ki-67. Secondary endpoints were the modulation of circulating biomarkers. Postmenopausal women with histologically confirmed estrogen receptor–positive breast cancer were randomly assigned to exemestane 25 mg/day (n = 50), or celecoxib 800 mg/day (n = 50), or placebo (n = 25) for 6 weeks before surgery. Changes in biomarkers were analyzed through an ANCOVA model adjusting for baseline values. Exemestane showed a median absolute 10% reduction in Ki-67 [from 22 (interquartile range, IQR, 16–27), to 8 (IQR 5–18)], and a 15% absolute reduction in PgR expression [from 50 (IQR 3–90) to 15 (IQR −0–30)] after 6 weeks of treatment. Exemestane significantly increased testosterone [median change 0.21 ng/mL, (IQR 0.12–0.35)], decreased SHBG [median change −14.6 nmol/L, (IQR −23.1 to −8.6)], decreased total and HDL cholesterol by −10 mg/dL (IQR −21–2) and −7 mg/dL, (IQR −14 to −2), respectively. Triglycerides were reduced by both agents [median change −0.5 mg/dL (IQR −17.5–13.5) and −8 mg/dL (IQR −28–9) for celecoxib and exemestane, respectively]. Exemestane showed a remarkable antiproliferative effect on breast cancer, whereas celecoxib did not affect breast cancer proliferation. Given the proven preventive efficacy of exemestane, these findings support the use of Ki-67 to explore the optimal exemestane dose and schedule in the prevention setting. Cancer Prev Res; 9(5); 349–56. ©2016 AACR.

Role of traditional and new biomarkers in breast carcinogenesis

In recent decades, several biomarkers have been investigated as predictors of breast cancer risk, development, prognosis and treatment efficacy. The detection of biomarkers strongly associated with breast carcinogenesis has an enormous potential, especially for selecting subjects at high risk of developing breast cancer who could benefit from chemopreventive treatments. Although the number of potential biomarkers continues to increase, a unique biomarker for breast cancer risk prediction has not been identified and it is probable that a panel of biomarkers will prove optimal. Further studies are needed to validate breast cancer biomarkers evaluation for individual risk assessment. This review summarizes the main biomarkers, which are important at different stages of breast carcinogenesis with updates from the recent literature.

Hereditary lobular breast cancer with an emphasis on E-cadherin genetic defect

Recent studies have reported germline CDH1 mutations in cases of lobular breast cancer (LBC) not associated with the classical hereditary diffuse gastric cancer syndrome. A multidisciplinary workgroup discussed genetic susceptibility, pathophysiology and clinical management of hereditary LBC (HLBC). The team has established the clinical criteria for CDH1 screening and results’ interpretation, and created consensus guidelines regarding genetic counselling, breast surveillance and imaging techniques, clinicopathological findings, psychological and decisional support, as well as prophylactic surgery and plastic reconstruction. Based on a review of current evidence for the identification of HLBC cases/families, CDH1 genetic testing is recommended in patients fulfilling the following criteria: (A) bilateral LBC with or without family history of LBC, with age at onset <50 years, and (B) unilateral LBC with family history of LBC, with age at onset <45 years. In CDH1 asymptomatic mutant carriers, breast surveillance with clinical examination, yearly mammography, contrast-enhanced breast MRI and breast ultrasonography (US) with 6-month interval between the US and the MRI should be implemented as a first approach. In selected cases with personal history, family history of LBC and CDH1 mutations, prophylactic mastectomy could be discussed with an integrative group of clinical experts. Psychodecisional support also plays a pivotal role in the management of individuals with or without CDH1 germline alterations. Ultimately, the definition of a specific protocol for CDH1 genetic screening and ongoing coordinated management of patients with HLBC is crucial for the effective surveillance and early detection of LBC.