Musculoskeletal adverse events associated with adjuvant aromatase inhibitors

The Risk of Lymphedema After Breast Cancer Surgery Should Not Restrict Necessary Hand Surgery Interventions

BACKGROUND

The purpose of this study was to evaluate the incidence of lymphedema onset or exacerbation in patients undergoing upper extremity interventions, both nonoperative and operative, after breast cancer surgery.

METHODS

The study inclusion criteria were the following: (1) prior history of breast cancer surgery or lymphedema from the cancer; (2) upper extremity intervention, ipsilateral to the breast cancer side; and (3) follow-up of at least 1 month. Patients were evaluated for demographic information, type of breast cancer procedure and hand intervention, number of lymph nodes dissected, preexisting lymphedema, exacerbation of lymphedema, and new-onset lymphedema.

RESULTS

A total of 161 patients undergoing 385 hand interventions (300 injections, 85 surgeries) were reviewed. Median follow-up was 31 months (range: 1-110). Nineteen patients had preexisting lymphedema ipsilateral to the hand procedure and none experienced an exacerbation of their lymphedema. Three patients developed new-onset lymphedema ipsilateral to their hand intervention at an average follow-up of 30 months (range: 4-67). One patient had a single injection and developed lymphedema over 5 years later. One had 2 injections in the same hand on the same date and developed lymphedema 3 months later. The third patient had 2 injections in the right hand, 1 injection and 1 surgery in the left hand, and developed either lymphedema or swelling due to rheumatoid arthritis in the right hand 1 year after the injections.

CONCLUSIONS

Patients who have undergone breast cancer surgery can safely undergo upper extremity intervention with low risk of lymphedema exacerbation or onset.

Characterization of Physical Function and Cancer-Related Physical Impairments in Hispanic Women With Breast Cancer: A Descriptive Study

Introduction: This study reports characteristics of Hispanic women with breast cancer with respect to physical function, body mass index (BMI), and depression. Methods: This retrospective study included 322 Hispanic women with breast cancer. Physical function and fatigue were assessed using the Patient Reported Outcomes Measurement System-Physical Function (PROMIS-PF) short form and PROMIS-Fatigue (PROMISE-F) short form. In addition, Timed Up and Go (TUG) test, sit to stand in 30 s (STS30) test, four-stage balance test (4SB), and grip strength (GS) were measured. Depression was identified using Patient Health Questionnaire (PHQ)-2 and extracted from medical chart. Results: Nearly 40.8% were obese, and 20.8% had depression. Compared to normal BMI patients, mean PROMIS-F score was significantly higher among overweight and obese patients. The mean STS30 score was significantly lower in obese patients, compared to normal BMI patients. Regression analysis showed that the odds of depression were higher with increasing TUG and lower PROMIS-F, STS30, and GS. Conclusion: Hispanic women with breast cancer have substantial loss of physical function, and this is exaggerated if they are obese, overweight, or depressed. Clinicians caring for this population should screen them for the presence of loss of physical function, BMI, and depression.

Effect of Tamoxifen on Proteome Expression during In Vitro Myogenesis in Murine Skeletal Muscle C2C12 Cells

Tamoxifen (TMX), a selective estrogen receptor modulator, is commonly used in the treatment of hormone-responsive cancers. However, the effects of TMX in anabolic tissues harboring estrogen receptors, such as skeletal muscle, are poorly understood. We report a tandem mass-tag approach to TMX-treated myogenesis in C2C12 cells, a well-characterized model of in vitro murine skeletal muscle differentiation. A longitudinal analysis of >10,000 proteins identified in untreated C2C12 myogenesis revealed a novel subset of 1,062 myogenically regulated proteins. These proteins clustered into five distinct longitudinal expression trends which significantly overlap those obtained in similar analyses performed in human myocytes. We document a specific functional enrichment for adiponectin-signaling unique to TMX-treated myogenesis, as well as a subset of 198 proteins that are differentially expressed in TMX-treated cells relative to controls at one or more stages of myogenesis, the majority of which were involved in steroid and lipid metabolism. Further analysis highlights metallothionein-1 as a novel target of TMX treatment at each stage of C2C12 myogenesis. Finally, we present a powerful, self-validating pipeline for analyzing the total proteomic response to in vitro treatment across every stage of muscle cell development which can be easily adapted to study the effects of other drugs on myogenesis.

Chronic pain and its correlates among long-term breast cancer survivors

PURPOSE

Chronic pain is a common symptom affecting quality of life for breast cancer survivors. However, its prevalence and correlate factors in long-term breast cancer survivors, particularly Asian women, are understudied. The reported study is to address these knowledge gaps.

METHODS

We evaluated pain severity and frequency, and their associations with clinical features and lifestyle factors among 3640 5-year breast cancer survivors who participated in the Shanghai Breast Cancer Survival Study. Demographic, clinical, and lifestyle information was collected at study enrollment, which occurred 6 months post-diagnosis, and pain was assessed at the 5-year post-diagnosis follow-up survey.

RESULTS

In total, 42% of participants reported experiencing pain. Pain is more prevalent among survivors with low educational attainment or low income. Multivariable polytomous regression analyses showed that pain was positively associated with metastasis or recurrence (moderate pain OR: 2.17, 95% CI: 1.45, 3.26, frequent pain OR: 1.92, 95% CI: 1.37, 2.70), triple negative status (infrequent pain OR: 1.36, 95% CI: 1.04, 1.78), obesity (frequent pain OR: 1.80, 95% CI: 1.41, 2.31), and multiple comorbidities. Exercise (OR: 0.65, 95%: 0.49, 0.88), chemotherapy (OR: 0.59, 95% CI: 0.41, 0.849), and HER2-positive and ER/PR-negative status (OR: 0.64, 95% CI: 0.43, 0.97) were inversely associated with moderate pain.

CONCLUSIONS

Chronic pain is highly prevalent among long-term breast cancer survivors in China and was associated with obesity, physical inactivity, and several clinical factors.

IMPLICATIONS FOR CANCER SURVIVORS

This study highlights the importance of promoting weight control and exercise to alleviate chronic pain.

Comparison of Anticancer Drug Toxicities: Paradigm Shift in Adverse Effect Profile

The inception of cancer treatment with chemotherapeutics began in the 1940s with nitrogen mustards that were initially employed as weapons in World War II. Since then, treatment options for different malignancies have evolved over the period of last seventy years. Until the late 1990s, all the chemotherapeutic agents were small molecule chemicals with a highly nonspecific and severe toxicity spectrum. With the landmark approval of rituximab in 1997, a new horizon has opened up for numerous therapeutic antibodies in solid and hematological cancers. Although this transition to large molecules improved the survival and quality of life of cancer patients, this has also coincided with the change in adverse effect patterns. Typically, the anticancer agents are fraught with multifarious adverse effects that negatively impact different organs of cancer patients, which ultimately aggravate their sufferings. In contrast to the small molecules, anticancer antibodies are more targeted toward cancer signaling pathways and exhibit fewer side effects than traditional small molecule chemotherapy treatments. Nevertheless, the interference with the immune system triggers serious inflammation- and infection-related adverse effects. The differences in drug disposition and interaction with human basal pathways contribute to this paradigm shift in adverse effect profile. It is critical that healthcare team members gain a thorough insight of the adverse effect differences between the agents discovered during the last twenty-five years and before. In this review, we summarized the general mechanisms and adverse effects of small and large molecule anticancer drugs that would further our understanding on the toxicity patterns of chemotherapeutic regimens.

Combinations of Calcitriol with Anticancer Treatments for Breast Cancer: An Update

Preclinical, clinical, and epidemiological studies indicate that vitamin D3 (VD) deficiency is a risk factor for the development of breast cancer. Underlying mechanisms include the ability of calcitriol to induce cell differentiation, inhibit oncogenes expression, and modify different signaling pathways involved in the control of cell proliferation. In addition, calcitriol combined with different kinds of antineoplastic drugs has been demonstrated to enhance their beneficial effects in an additive or synergistic fashion. However, a recognized adjuvant regimen based on calcitriol for treating patients with breast cancer has not yet been fully established. Accordingly, in the present work, we review and discuss the preclinical and clinical studies about the combination of calcitriol with different oncological drugs, aiming to emphasize its main therapeutic benefits and opportunities for the treatment of this pathology.

Reconsidering Aromatase for Breast Cancer Treatment: New Roles for an Old Target

The current therapeutic approach for the treatment of hormone dependent breast cancer includes interference with estrogen receptors via either selective modulators or estrogens deprivation, by preventing their biosynthesis with aromatase inhibitors. Severe side effects and acquired resistance are drawbacks of both drug classes, and the efforts to overcome these issues still allow for research in this field to be animated. This review reports on recent findings that have opened new avenues for reconsidering the role of aromatase enzymes (and estrogen receptors) leading to the possibility of looking at well-known targets in a new perspective.

The Effects of Pharmacological and Non-Pharmacological Interventions on Symptom Management and Quality of Life among Breast Cancer Survivors Undergoing Adjuvant Endocrine Therapy: A Systematic Review

Breast cancer survivors need to undergo adjuvant endocrine therapy after completion of curative treatments to prevent disease recurrence. These individuals often experience symptoms which are detrimental to their quality of life (QOL). Implementation of interventions for effective symptom management among these survivors is warranted. This review provides an overview of studies on the effectiveness of the previously developed interventions for breast cancer survivors undergoing adjuvant endocrine therapy on symptom alleviation and enhancement of QOL or health-related QOL (HRQOL). Five electronic databases were employed in the literature search. Study selection, data extraction and critical appraisal of the included studies were conducted by three authors independently. Twenty-four studies were included. Both pharmacological and non-pharmacological interventions are effective in addressing the symptoms associated with adjuvant endocrine therapy among the breast cancer survivors, and in improving their QOL, although discrepancies were noted between the studies in terms of the significance of these effects. Pharmacological and non-pharmacological interventions can be effective for symptom management among breast cancer survivors. Their implementation is recommended for effective survivorship care for these individuals. Further research on intervention development for breast cancer survivors is recommended to provide further evidence for the utility of the explored interventions in survivorship care for these patients.

Clinical Features and Outcomes of Invasive Breast Cancer: Age-Specific Analysis of a Modern Hospital-Based Registry

PURPOSE

We evaluated the clinical features and outcomes of invasive breast cancer (BC) among different age groups by analyzing a modern BC registry including subtypes and treatment information.

METHODS

This was a retrospective cohort study of 6,405 women aged 18 years or older with pathologically confirmed stage I, II, or III BC who underwent curative surgery followed by adjuvant therapy at a university-based hospital in Seoul, South Korea, between January 2003 and December 2011. The study end point was all-cause mortality. We used Cox proportional hazards models and hazard ratios (HRs) with 95% CIs calculated after adjusting for age, body mass index, stage, subtype, and treatment, including type of surgery and use of chemotherapy, radiation therapy, hormone therapy, and targeted therapy.

RESULTS

During 36,360 person-years of follow-up (median follow-up: 5.45 years; interquartile range, 4.3-7.1), 256 deaths were reported (mortality rate, 7.0/1,000 person-years). The adjusted HR for all-cause mortality was higher in patients older than 40 years (HR, 2.03; 95% CI, 1.44 to 2.87) and older than 60 years (HR, 2.35; 95% CI, 1.63 to 3.39) than in patients aged 40 to 49 years. Across age groups, advanced stage at diagnosis, luminal type as well as triple-negative BC, and not receiving adjuvant treatment were associated with increased risk of mortality.

CONCLUSION

A strong J-shaped relationship was observed between age and mortality, indicating worse clinical outcomes in young and old patients. This study suggested a possible benefit of personalized BC screening examination and precise and active treatment strategies to reduce BC-related mortality.

Late breast cancer treatment-related symptoms and functioning: associations with physical activity adoption and maintenance during a lifestyle intervention for rural survivors

PURPOSE

Physical activity may be difficult for survivors with poorer functioning following primary treatment. The study examined whether late symptoms of breast cancer treatment impact PA adoption (0-6 months) and maintenance (6-18 months) during a weight management intervention, and whether late symptoms influence PA when accounting for overall functioning.

METHODS

Secondary analyses were conducted using a sample of survivors participating in a weight management intervention and who provided valid weight and accelerometer data at baseline and 6 months (N = 176). The Breast Cancer Prevention Trial Symptom Checklist (BCPT) assessed late treatment-related symptoms. SF-12 Physical Component Scale (PCS) and Mental Component Scale (MCS) scores assessed functioning.

RESULTS

Change in bouted moderate to vigorous physical activity (MVPA) min/week from baseline to 6 months was not associated with BCPT scales (all p values > 0.05). When adding SF-12 scores to the model, change in bouted MVPA min/week was significantly associated with the PCS (p = 0.045). Change in MVPA min/week from 6 to 18 months was significantly associated with cognitive symptoms (p = 0.004), but not musculoskeletal or vasomotor symptoms (p values > 0.05). When adding 6-month SF-12 scores to the model, MVPA min/week was significantly associated with PCS (p = 0.001) and MCS (p = 0.028); however, BCPT cognitive problems score became non-significant (p > 0.05).

CONCLUSIONS

Poorer physical functioning was associated with lower PA adoption, and poorer mental and physical functioning was associated with lower maintenance of PA, while late symptoms generally were not. Interventionists should consider level of functioning when identifying individual PA goals during weight management interventions.

Traditional Chinese Medicine Bionic Tiger Bone Powder for the Treatment of AI-Associated Musculoskeletal Symptoms

Background. Aromatase inhibitors (AIs) are used for adjuvant therapy of breast cancer; however AIMSS (AI-Associated Musculoskeletal Symptoms) can negatively affect quality of life and compliance. Most patients in China moved to TCM (traditional Chinese medicine) for help. TB (tiger bone) is used to treat bone disease, whose main ingredients are calcium and collagen. The objective of this study was to evaluate whether the TB prevented AIMSS in postmenopausal women with ER/PR+ breast cancer. Methods. We conducted a randomized, blind, controlled study of comparing TB versus placebo for 12 weeks in postmenopausal women with breast cancer who have taken AI for less than a month. Patients completed the M-BPI, VAS, and FACT-B at baseline, 6 weeks, and 12 weeks. M-BPI and VAS were used as the primary outcomes. FACT-B was used as the secondary outcome. Serum E₂ and FSH were tested every 6 weeks. Results. Of 70 evaluable cases, 8 of 35 patients (22.9%) developed new or worsening point symptoms in TB group, compared to 21 of 35 (60%) in placebo group (P < 0.001). We also found differences between 2 groups in average pain (2 to 5.6), worst pain (3.9 to 8), pain interference severity (1.9 to 5.3), stiffness (2.4 to 6.9), and joint symptom interference (1.8 to 5.7), all P < 0.001; similar findings were seen in VAS value (3 to 6.6) at the end of intervention. HRQoL measured by FACT-B (P < 0.05) was improved. No change of serum estradiol and FSH between two groups. Conclusions. TB appeared to be effective and safe in the prevention of AIMSS. This trial is registered with ChiCTR-IPR-15007081.

Influence of vitamin D signaling on hormone receptor status and HER2 expression in breast cancer

PURPOSE

Breast cancer is a significant global public health issue. It is the leading cause of death among women around the world, with an incidence increasing annually. In recent years, there has been more and more information in the literature regarding a protective role of vitamin D in cancer. Increasingly preclinical and clinical studies suggest that vitamin D optimal levels can reduce the risk of breast cancer development and regulate cancer-related pathways.

METHOD

In this review, we focus on the importance of vitamin D in breast cancers, discussing especially the influence of vitamin D signaling on estrogen receptor and human epidermal growth factor receptor 2 (HER2), two major biomarkers of breast cancer today.

CONCLUSION

We discuss the possibility of actual and future targeted therapeutic approaches for vitamin D signaling in breast cancer.

Use of complementary therapies for side effect management in breast cancer: evidence and rationale

Women diagnosed with breast cancer can experience chronic side effects after curative treatment concludes, negatively impacting survivorship. The most prevalent side effects addressed in the medical and nursing literature include symptoms such as hot flashes, fatigue, myalgias/arthralgias and cognitive impairment. Complementary therapies, particularly natural products including herbs, dietary supplements, vitamins, minerals, and probiotics, and mind–body techniques that include such modalities as yoga, meditation, massage, acupuncture, relaxation, tai chi and hypnosis show promise for treatment of some of these symptoms associated with cancer care. However, the research in this area is nascent and much more work is needed to understand symptom physiology and mechanisms of action of complementary therapies. The purpose of this paper was to summarize key evidence from Phase II and III randomized clinical trials in order to provide guidance to distinguish promising versus nonpromising interventions for symptom management.

Synthesis of Triphenylethylene Bisphenols as Aromatase Inhibitors That Also Modulate Estrogen Receptors

A series of triphenylethylene bisphenol analogues of the selective estrogen receptor modulator (SERM) tamoxifen were synthesized and evaluated for their abilities to inhibit aromatase, bind to estrogen receptor α (ER-α) and estrogen receptor β (ER-β), and antagonize the activity of β-estradiol in MCF-7 human breast cancer cells. The long-range goal has been to create dual aromatase inhibitor (AI)/selective estrogen receptor modulators (SERMs). The hypothesis is that in normal tissue the estrogenic SERM activity of a dual AI/SERM could attenuate the undesired effects stemming from global estrogen depletion caused by the AI activity of a dual AI/SERM, while in breast cancer tissue the antiestrogenic SERM activity of a dual AI/SERM could act synergistically with AI activity to enhance the antiproliferative effect. The potent aromatase inhibitory activities and high ER-α and ER-β binding affinities of several of the resulting analogues, together with the facts that they antagonize β-estradiol in a functional assay in MCF-7 human breast cancer cells and they have no E/Z isomers, support their further development in order to obtain dual AI/SERM agents for breast cancer treatment.

Adaptation of an Evidence-Based Arthritis Program for Breast Cancer Survivors on Aromatase Inhibitor Therapy Who Experience Joint Pain

Adding aromatase inhibitors (AIs) to adjuvant treatment of postmenopausal women with hormone-receptor-positive breast cancer significantly reduces cancer recurrence. A common side effect of AIs is noninflammatory joint pain and stiffness (arthralgia) similar to arthritis symptoms. An evidence-based walking program developed by the Arthritis Foundation - Walk With Ease (WWE) - reduces arthritis-related joint symptoms. We hypothesized that WWE may also reduce AI-associated arthralgia. However, the potential for different barriers and facilitators to physical activity for these 2 patient populations suggested a need to adapt WWE before testing it with breast cancer survivors. We conducted qualitative research with 46 breast cancer survivors to explore program modification and inform the development of materials for an adapted program (Walk With Ease-Breast Cancer). Our process parallels the National Cancer Institute's Research-Tested Intervention Programs (RTIPs) guidelines for adapting evidence-based programs for cancer populations. Findings resulted in a customized 8-page brochure to supplement existing WWE materials.

Design and synthesis of norendoxifen analogues with dual aromatase inhibitory and estrogen receptor modulatory activities

Both selective estrogen receptor modulators and aromatase inhibitors are widely used for the treatment of breast cancer. Compounds with both aromatase inhibitory and estrogen receptor modulatory activities could have special advantages for treatment of breast cancer. Our previous efforts led to the discovery of norendoxifen as the first compound with dual aromatase inhibitory and estrogen receptor binding activities. To optimize its efficacy and aromatase selectivity versus other cytochrome P450 enzymes, a series of structurally related norendoxifen analogues were designed and synthesized. The most potent compound, 4'-hydroxynorendoxifen (10), displayed elevated inhibitory potency against aromatase and enhanced affinity for estrogen receptors when compared to norendoxifen. The selectivity of 10 for aromatase versus other cytochrome P450 enzymes was also superior to norendoxifen. 4'-Hydroxynorendoxifen is therefore an interesting lead for further development to obtain new anticancer agents of potential value for the treatment of breast cancer.

Optimal management of breast cancer in the elderly patient: current perspectives

Breast cancer (BC) is the most common female malignancy in the world and almost one third of cases occur after 70 years of age. Optimal management of BC in the elderly is a real challenge and requires a multidisciplinary approach, mainly because the elderly population is heterogeneous. In this review, we describe the various possibilities of treatment for localized or metastatic BC in an aging population. We provide an overview of the comprehensive geriatric assessment, surgery, radiotherapy, and adjuvant therapy for early localized BC and of chemotherapy and targeted therapies for metastatic BC. Finally, we attempt to put into perspective the necessary balance between the expected benefits and risks, especially in the adjuvant setting.

Polymorphic genetic variations of cytochrome P450 19A1 and T-cell leukemia 1A genes in the Tamil population

Aromatase inhibitors (AIs) are anti-neoplastic drugs widely used for the treatment of endocrine responsive breast carcinoma in postmenopausal women. Drug disposition, efficacy and tolerability of these agents are influenced by germ-line polymorphisms in the sequence of the genes encoding CYP19A1 and TCL1A proteins. In the current work, we aimed to determine the haplotype structures, linkage disequilibrium (LD) patterns, and allele and genotype frequency distribution of pharmacologically important variants from two genes (CYP19A1 and TCL1A) in Tamil population and assessed their ethnic differences. DNA derived from peripheral leukocytes of 111 healthy subjects were genotyped for 15 pharmacogenetic variants by real time thermocycler through allelic discrimination method using TaqMan 5' nuclease genotyping assay. The polymorphic variant allele frequencies of CYP19A1 were 42.3% (rs4646, T), 18% (rs10046, T), 36% (rs700519, T), 16.7% (rs700518, G), 26.1% (rs727479, G), 18% (rs4775936, T), 32% (rs10459592, G), 15.3% (rs1062033, C), 33.8% (rs749292, A), 40.1% (rs6493497, T) and 40.1% (rs7176005, G). TCL1A gene allele frequencies were 26.1% (rs7158782, G), 27% (rs7159713, G), 21.2% (rs2369049, G) and 27.5% (rs11849538, G). Comparing our data across the 5 HapMap populations (CEU, GIH, HCB, JPT and YRI) huge inter-ethnic differences were exhibited in the variant allele frequencies, LD patterns and haplotype blocks. Our results emphasize the importance of normative frequency documentation and will offer significant clinical relevance in personalizing AIs therapy.

Genotype, allele and haplotype frequencies of four TCL1A gene polymorphisms associated with musculoskeletal toxicity in the South Indian descent

INTRODUCTION

Decline in circulating estrogen levels causes lessening of bone mass accompanied with musculoskeletal pain, which is the primary cause of treatment discontinuation in patients taking aromatase inhibitors. Evidence from recent genome-wide association studies (GWAS) suggests that the genetic variability underlying TCL1A gene increases the risk of aromatase inhibitors (AIs) - induced musculoskeletal toxicity. Currently, no data is available on the frequency distribution of TCL1A gene polymorphisms in Indians.

METHODS

In this pilot study, we used TaqMan fluorescent probes to assess the genotypes of four TCL1A gene polymorphisms associated with musculoskeletal toxicity in 247 healthy homogenous South Indian subjects on real time thermocycler. Haplotype estimation and pairwise linkage disequilibrium (LD) analysis were executed by Haploview.

RESULTS

The incidence of polymorphic variant allele (G) frequencies of rs7158782, rs7159713, rs2369049 and rs11849538 were 22.1%, 23.5%, 18.2% and 22.9% in the study population, respectively. The polymorphisms were found to be in complete LD with each other. Four different haplotypes, each of which having a frequency of above 1% were inferred in South Indians using an expectation-maximization algorithm. Notably, three haplotypes were found to be population specific viz H4 A-A-A-G (1.2%) for South India, H5 G-G-A-C (1.3%) for JPT and H6 G-G-G-C (40.4%) for YRI. Further, H3 G-G-A-G (2.3-16.3%) haplotype occurs primarily in Asians and is virtually absent in Africans. Overall, the genetic variability and haplotype profile of South Indian population revealed significant inter-racial variability compared with HapMap data.

CONCLUSION

This documentation contributes for further investigations on the pharmacogenetics of AIs in South Indians.

Synthesis of mixed (E,Z)-, (E)-, and (Z)-norendoxifen with dual aromatase inhibitory and estrogen receptor modulatory activities

The first synthesis of the tamoxifen metabolite norendoxifen is reported. This included syntheses of (E)-norendoxifen, (Z)-norendoxifen, and (E,Z)-norendoxifen isomers. (Z)-Norendoxifen displayed affinity for aromatase (Ki 442 nM), estrogen receptor-α (EC50 17 nM), and estrogen receptor-β (EC50 27.5 nM), while the corresponding values for (E)-norendoxifen were aromatase (Ki 48 nM), estrogen receptor-α (EC50 58.7 nM), and estrogen receptor-β (EC50 78.5 nM). Docking and energy minimization studies were performed with (E)-norendoxifen on aromatase, and the results provide a foundation for structure-based drug design. The oral pharmacokinetic parameters for (E,Z)-norendoxifen were determined in mice, and (Z)-norendoxifen was found to result in significantly higher plasma concentrations and exposures (AUC values) than (E)-norendoxifen. The affinities of both isomers for aromatase and the estrogen receptors, as well as the pharmacokinetic results, support the further development of norendoxifen and its analogues for breast cancer treatment.

Influence of drugs on vitamin D and calcium metabolism

In the past, interactions between drugs and vitamin D have received only little or no attention in the health care practices. However, since more and more drugs are used for the treatment of patients, this topic is increasingly relevant. Several drugs can interfere with the vitamin D and bone metabolism. Drugs that activate the pregnane X receptor can disrupt vitamin D metabolism and vitamin D function. Beside this, the medication oriented supplementation of vitamin D can ameliorate the pharmacologic action of some drugs, such as bisphosphonates, cytostatics and statins.

The association between breast cancer prognostic indicators and serum 25-OH vitamin D levels

BACKGROUND

Studies show that women with low vitamin D levels have an increased risk of breast cancer (BC) incidence and mortality, but there is a lack of research examining vitamin D levels and prognostic variables in BC patients. The aim of this study is to examine 25-OH vitamin D levels between BC cases and controls and by prognostic indicators among BC cases.

METHODS

25-OH vitamin D levels were collected from 194 women who underwent BC surgery and 194 cancer-free (CF) controls at the University of Rochester between January 2009 and October 2010. Mean 25-OH vitamin D levels and odds ratios (OR) were calculated by case/control status for the overall cohort and by prognostic indicators (invasiveness, ER status, triple-negative status, Oncotype DX score, molecular phenotype) for BC cases.

RESULTS

BC cases had significantly lower 25-OH vitamin D levels than CF controls (BC: 32.7 ng/mL vs. CF: 37.4 ng/mL; P = .02). In case-series analyses, women with suboptimal 25-OH vitamin D concentrations (<32 ng/mL) had significantly higher odds of having ER- (OR = 2.59, 95% confidence interval [95% CI] = 1.08-6.23) and triple-negative cancer (OR = 3.15, 95% CI = 1.05-9.49) than those with optimal 25-OH D concentrations. Women with basal-like phenotype had lower 25-OH vitamin D levels than women luminal A phenotype (basal-like: 24.2 ng/mL vs. luminal A: 32.8 ng/mL; P = 0.04).

CONCLUSIONS

BC patients with a more aggressive molecular phenotype (basal-like) and worse prognostic indicators (ER- and triple-negative) had lower mean 25-OH vitamin D levels. Further research is needed to elucidate the biological relationship between vitamin D and BC progression.

Aromatase inhibitors, estrogens and musculoskeletal pain: estrogen-dependent T-cell leukemia 1A (TCL1A) gene-mediated regulation of cytokine expression

Introduction

Arthralgias and myalgias are major side effects associated with aromatase inhibitor (AI) therapy of breast cancer. In a recent genome-wide association study, we identified SNPs - including one that created an estrogen response element near the 3' end of the T-cell leukemia 1A (TCL1A) gene - that were associated with musculoskeletal pain in women on adjuvant AI therapy for breast cancer. We also showed estrogen-dependent, SNP-modulated variation in TCL1A expression and, in preliminary experiments, showed that TCL1A could induce IL-17RA expression. In the present study, we set out to determine whether these SNPs might influence cytokine expression and effect more widely, and, if so, to explore the mechanism of TCL1A-related AI-induced side effects.

Methods

The functional genomic experiments performed included determinations of TCL1A, cytokine and cytokine receptor expression in response to estrogen treatment of U2OS cells and lymphoblastoid cell lines that had been stably transfected with estrogen receptor alpha. Changes in mRNA and protein expression after gene knockdown and overexpression were also determined, as was NF-κB transcriptional activity.

Results

Estradiol (E2) increased TCL1A expression and, in a TCL1A SNP-dependent fashion, also altered the expression of IL-17, IL-17RA, IL-12, IL-12RB2 and IL-1R2. TCL1A expression was higher in E2-treated lymphoblastoid cell lines with variant SNP genotypes, and induction of the expression of cytokine and cytokine receptor genes was mediated by TCL1A. Finally, estrogen receptor alpha blockade with ICI-182,780 in the presence of E2 resulted in greatly increased NF-κB transcriptional activity, but only in cells that carried variant SNP genotypes. These results linked variant TCL1A SNP sequences that are associated with AI-dependent musculoskeletal pain with increased E2-dependent TCL1A expression and with downstream alterations in cytokine and cytokine receptor expression as well as NF-κB transcriptional activity.

Conclusions

SNPs near the 3' terminus of TCL1A were associated with AI-dependent musculoskeletal pain. E2 induced SNP-dependent TCL1A expression, which in turn altered IL-17, IL-17RA, IL-12, IL-12RB2, and IL-1R2 expression as well as NF-κB transcriptional activity. These results provide a pharmacogenomic explanation for a clinically important adverse drug reaction as well as insights into a novel estrogen-dependent mechanism for the modulation of cytokine and cytokine receptor expression.

The time since last menstrual period is important as a clinical predictor for non-steroidal aromatase inhibitor-related arthralgia

Background

The clinical predictors of aromatase inhibitor-related arthralgia (AIA), a drug-related adverse reaction of aromatase inhibitors (AIs), remain unclear.

Methods

AIA was prospectively surveyed every 4 months in 328 postmenopausal breast cancer patients administered a non-steroidal AI (anastrozole). Various clinicopathological parameters were recorded and analyzed (chi-square test, Fisher's exact test and logistic regression analysis).

Results

The mean observation period was 39.9 months. AIA manifested in 114 patients (34.8%), with peaks of onset at 4 (33.7%) and 8 months (11.4%) after starting AI administration. Some cases manifested even after 13 months. AIA tended to occur in younger patients (incidences of 46.3%, 37.4% and 28.0% for ages of < 55, 55-65 and > 65 years, respectively (p = 0.063)) and decreased significantly with the age at menarche (53.3%, 35.3% and 15.4% for < 12, 12-15 and > 15 years, respectively (p = 0.036)). The incidences were 45.1%, 46.3 and 25.1% for the time since the last menstrual period (LMP) < 5 years, 5-10 years and > 10 years, being significantly lower at > 10 years (p < 0.001). In logistic regression analysis, the AIA incidence was significantly lower in the time since LMP > 10-year group versus the < 5-year group (odds ratio 0.44, p = 0.002), but the age at menarche showed no association. AIA manifested significantly earlier (≤ 6 months) as the time since LMP became shorter (< 5 years).

Conclusion

AIA tends to manifest early after starting AI, but some cases show delayed onset. The incidence was significantly lower in patients with a duration of > 10 years since LMP. When the time since LMP was short, the onset of AIA was significantly earlier after starting AI administration.

Androgens and musculoskeletal symptoms among breast cancer patients on aromatase inhibitor therapy

Aromatase inhibitors (AIs), the adjuvant hormonal treatment of choice for postmenopausal estrogen receptor-positive breast cancer, are associated with an increased risk of musculoskeletal symptoms. The underlying cause of the symptoms is often attributed to estrogen depletion, yet all women treated with AIs have low estrogen levels and only a subset develop symptoms. Concentrations of circulating androgens may be mediating factors contributing to these side effects. The purpose of this study was to examine changes in androgen concentrations among women initiating AI therapy and to determine if concentrations are associated with musculoskeletal symptoms. Data were analyzed from a cohort study of 74 breast cancer patients for whom AI therapy was planned. Questionnaire data on symptoms were collected and blood was drawn prior to AI therapy (baseline) and then again at 3 and 6 months after baseline. Blood was assayed for testosterone, androstenedione, dehydroepiandrosterone-sulfate (DHEAS), and sex hormone-binding globulin (SHBG). Free testosterone index (FTI) values were calculated using testosterone and SHBG measurements. The results showed that concentrations of all of the androgens increased over the study period, with statistically significant differences from baseline concentrations observed for the FTI at 3 and 6 months and for DHEAS at 6 months. Additionally, breast cancer patients with new onset or worsening of pain over the study period had a significantly smaller change in mean DHEAS concentration from baseline to 3 months (P = 0.04) and a marginally significant smaller change in mean DHEAS concentration from baseline to 6 months (P = 0.1) compared to those who reported no pain at all time points or no worsening of pain across the study period. Changes in testosterone, androstenedione, and the FTI were not associated with the onset or worsening of pain during the study period. Findings from this study suggest that higher DHEAS concentrations are associated with less AI-associated pain and should be further investigated.

The effect of various vitamin D supplementation regimens in breast cancer patients

Vitamin D deficiency in the patients treated for breast cancer is associated with numerous adverse effects (bone loss, arthralgia, and falls). The first aim of this study was to assess vitamin D status, determined by 25-OH vitamin D levels, among women diagnosed with breast cancer according to demographic/clinical variables and bone mineral density (BMD). The second aim of this study was to evaluate the effect of daily low-dose and weekly high-dose vitamin D supplementation on 25-OH vitamin D levels. This retrospective study included 224 women diagnosed with stage 0-III breast cancer who received treatment at the James P. Wilmot Cancer Center at the University of Rochester Medical Center. Total 25-OH vitamin D levels (D(2) + D(3)) were determined at baseline for all participants. Vitamin D deficiency was defined as a 25-OH vitamin D level < 20 ng/ml, insufficiency as 20-31 ng/ml, and sufficiency as ≥32 ng/ml. BMD was assessed during the period between 3 months before and 6 months following the baseline vitamin D assessment. Based on the participants' baseline levels, they received either no supplementation, low-dose supplementation (1,000 IU/day), or high-dose supplementation (≥50,000 IU/week), and 25-OH vitamin D was reassessed in the following 8-16 weeks. Approximately 66.5% had deficient/insufficient vitamin D levels at baseline. Deficiency/insufficiency was more common among non-Caucasians, women with later-stage disease, and those who had previously received radiation therapy (P < 0.05). Breast cancer patients with deficient/insufficient 25-OH vitamin D levels had significantly lower lumbar BMD (P = 0.03). Compared to the no-supplementation group, weekly high-dose supplementation significantly increased 25-OH vitamin D levels, while daily low-dose supplementation did not significantly increase levels. Vitamin D deficiency and insufficiency were common among women with breast cancer and associated with reduced BMD in the spine. Clinicians should carefully consider vitamin D supplementation regimens when treating vitamin D deficiency/insufficiency in breast cancer patients.