Systematic review of aromatase inhibitors in the first-line treatment for hormone sensitive advanced or metastatic breast cancer. Breast Cancer Res Treat. 2010;123:9-24. [PMID: 20535542 DOI: 10.1007/s10549-010-0974-0]

Design and synthesis new indole-based aromatase/iNOS inhibitors with apoptotic antiproliferative activity

The present study details the design, synthesis, and bio-evaluation of indoles 3-16 as dual inhibitors of aromatase and inducible nitric oxide synthase (iNOS)with antiproliferative activity. The study evaluates the antiproliferative efficacy of 3-16 against various cancer cell lines, highlighting hybrids 12 and 16 for their exceptional activity with GI50 values of 25 nM and 28 nM, respectively. The inhibitory effects of the most active hybrids 5, 7, 12, and 16, on both aromatase and iNOS were evaluated. Compounds 12 and 16 were investigated for their apoptotic potential activity, and the results showed that the studied compounds enhance apoptosis by activating caspase-3, 8, and Bax and down-regulating the anti-apoptotic Bcl-2. Molecular docking studies are intricately discussed to confirm most active hybrids' 12- and 16-binding interactions with the aromatase active site. Additionally, our novel study discussed the ADME characteristics of derivatives 8-16, highlighting their potential as therapeutic agents with reduced toxicity.

Metastatic Breast Cancer: Prolonging Life in Routine Oncology Care

Overall survival (OS) of patients with metastatic breast cancer (MBC) has improved within controlled clinical trials. Whether these advances translate into improved OS in routine care is controversial. We therefore analyzed retrospectively unselected female patients from five oncology group practices and one university outpatient clinic, whose initial diagnosis of MBC was between 1995 and 2022. A total of 1610 patients with a median age of 63 years (23-100) were evaluated. In all, 82.9% had hormone-receptor-positive disease, and 23.8% were HER2-positive. Evaluation in time cohorts by initial MBC diagnosis date showed a continuous prolongation of median OS from 31.6 months (0.5-237.3+) (1995-2000) to 48.4 months (0.4-61.1+) (2018-2022) (p = 0.003). Univariable analyses showed a significant dependence on the time cohort of diagnosis, metastatic status at initial diagnosis, age at metastasis, hormone and HER2 status, general condition, metastasis localization, and the number of affected organs. A multivariable analysis revealed a significant dependence of survival probability on receptor status, general condition, and number of metastatic sites, as well as the time between initial breast cancer diagnosis and the diagnosis date of MBC in months. In sum, OS of patients with MBC has improved continuously and significantly in routine care over the last 27 years.

Breast Tumor Metastasis and Its Microenvironment: It Takes Both Seed and Soil to Grow a Tumor and Target It for Treatment

Metastasis remains a major challenge in treating breast cancer. Breast tumors metastasize to organ-specific locations such as the brain, lungs, and bone, but why some organs are favored over others remains unclear. Breast tumors also show heterogeneity, plasticity, and distinct microenvironments. This contributes to treatment failure and relapse. The interaction of breast cancer cells with their metastatic microenvironment has led to the concept that primary breast cancer cells act as seeds, whereas the metastatic tissue microenvironment (TME) is the soil. Improving our understanding of this interaction could lead to better treatment strategies for metastatic breast cancer. Targeted treatments for different subtypes of breast cancers have improved overall patient survival, even with metastasis. However, these targeted treatments are based upon the biology of the primary tumor and often these patients' relapse, after therapy, with metastatic tumors. The advent of immunotherapy allowed the immune system to target metastatic tumors. Unfortunately, immunotherapy has not been as effective in metastatic breast cancer relative to other cancers with metastases, such as melanoma. This review will describe the heterogeneic nature of breast cancer cells and their microenvironments. The distinct properties of metastatic breast cancer cells and their microenvironments that allow interactions, especially in bone and brain metastasis, will also be described. Finally, we will review immunotherapy approaches to treat metastatic breast tumors and discuss future therapeutic approaches to improve treatments for metastatic breast cancer.

Tailoring Potential Natural Compounds for the Treatment of Luminal Breast Cancer

Breast cancer (BC) is the most diagnosed cancer worldwide, mainly affecting the epithelial cells from the mammary glands. When it expresses the estrogen receptor (ER), the tumor is called luminal BC, which is eligible for endocrine therapy with hormone signaling blockade. Hormone therapy is essential for the survival of patients, but therapeutic resistance has been shown to be worrying, significantly compromising the prognosis. In this context, the need to explore new compounds emerges, especially compounds of plant origin, since they are biologically active and particularly promising. Natural products are being continuously screened for treating cancer due to their chemical diversity, reduced toxicity, lower side effects, and low price. This review summarizes natural compounds for the treatment of luminal BC, emphasizing the activities of these compounds in ER-positive cells. Moreover, their potential as an alternative to endocrine resistance is explored, opening new opportunities for the design of optimized therapies.

Targeting the formation of estrogens for treatment of hormone dependent diseases-current status

Local formation and action of estrogens have crucial roles in hormone dependent cancers and benign diseases like endometriosis. Drugs that are currently used for the treatment of these diseases act at the receptor and at the pre-receptor levels, targeting the local formation of estrogens. Since 1980s the local formation of estrogens has been targeted by inhibitors of aromatase that catalyses their formation from androgens. Steroidal and non-steroidal inhibitors have successfully been used to treat postmenopausal breast cancer and have also been evaluated in clinical studies in patients with endometrial, ovarian cancers and endometriosis. Over the past decade also inhibitors of sulfatase that catalyses the hydrolysis of inactive estrogen-sulfates entered clinical trials for treatment of breast, endometrial cancers and endometriosis, with clinical effects observed primarily in breast cancer. More recently, inhibitors of 17beta-hydroxysteroid dehydrogenase 1, an enzyme responsible for formation of the most potent estrogen, estradiol, have shown promising results in preclinical studies and have already entered clinical evaluation for endometriosis. This review aims to provide an overview of the current status of the use of hormonal drugs for the major hormone-dependent diseases. Further, it aims to explain the mechanisms behind the -sometimes- observed weak effects and low therapeutic efficacy of these drugs and the possibilities and the advantages of combined treatments targeting several enzymes in the local estrogen formation, or drugs acting with different therapeutic mechanisms.

Design of Novel Letrozole Analogues Targeting Aromatase for Breast Cancer: Molecular Docking, Molecular Dynamics, and Theoretical Studies on Gold Nanoparticles

The use of aromatase inhibitors is an established therapy for estrogen-dependent breast cancer in postmenopausal women. However, the only commercially available aromatase inhibitor, letrozole, is not highly selective; in addition to aromatase, it has an affinity for binding to desmolase, an enzyme involved in steroidogenesis, which explains the main side effects. Therefore, we designed new compounds based on the structure of letrozole. More than five thousand compounds were constructed based on the letrozole structure. Then, these compounds were screened for their binding ability toward the target protein, aromatase. Quantum docking, Glide docking, and ADME studies showed 14 new molecules with docking scores of ≤-7 kcal/mol, compared to the docking score of -4.109 kcal/mol of the reference, letrozole. Moreover, molecular dynamics (MD) and post-MD MM-GBSA calculations were calculated for the top three compounds, and the results supported in their interaction's stability. Finally, the density-functional theory (DFT) study applied to the top compound to study the interaction with gold nanoparticles revealed the most stable position for the interaction with the gold nanoparticles. The results of this study confirmed that these newly designed compounds could be useful starting points for lead optimization. Further in vitro and in vivo studies are recommended for these compounds to verify these promising results experimentally.

The transdermal cream of Formestane anti-breast cancer by controlling PI3K-Akt pathway and the tumor immune microenvironment

Background

Treatment of ER+ breast cancer with intramuscular formulation of Formestane (4-OHA) shrinks the tumor within weeks. Since the tedious way of intramuscular administration and side effects are not suited for adjuvant treatment, Formestane was withdrawn from the market. A new transdermal formulation of 4-OHA cream may overcome the defects and retain the effect of shrinking the breast cancer tumor. However, the effects of 4-OHA cream on breast cancer need further confirmatory studies.

Methods

In this work, in vivo, the influence of 4-OHA cream on breast cancer was evaluated using the mode of 7,12-dimethylbenz(a)anthracene (DMBA) induced rat mammary cancer. We explored the common molecule mechanisms of action of 4-OHA cream and its injection formulation on breast cancer through RNA- sequencing-based transcriptome analysis and several biochemical experiments.

Results

The results showed that the cream substantially reduced the entire quantity, size, and volum of tumors in DMBA-treated rats consistent with 4-OHA injection, and indicated that there were comprehensive signals involved in 4-OHA antitumor activity, such as ECM-receptor interaction, focal adhesion, PI3K-Akt signaling pathway, and proteoglycans in cancer. In addition, we observed that both 4-OHA formulations could enhance immune infiltration, especially CD8+ T cells, B cells, natural killer cells, and macrophages infiltration, in the DMBA-induced mammary tumor tissues. The antitumor effects of 4-OHA partly depended on these immune cells.

Conclusion

4-OHA cream could inhibit breast cancer growth as its injection formulation and may provide a new way for neoadjuvant treatment of ER+ breast cancer.

Novel Arylsulfonylhydrazones as Breast Anticancer Agents Discovered by Quantitative Structure-Activity Relationships

Breast cancer (BC) is the second leading cause of cancer death in women, with more than 600,000 deaths annually. Despite the progress that has been made in early diagnosis and treatment of this disease, there is still a significant need for more effective drugs with fewer side effects. In the present study, we derive QSAR models with good predictive ability based on data from the literature and reveal the relationships between the chemical structures of a set of arylsulfonylhydrazones and their anticancer activity on human ER+ breast adenocarcinoma and triple-negative breast (TNBC) adenocarcinoma. Applying the derived knowledge, we design nine novel arylsulfonylhydrazones and screen them in silico for drug likeness. All nine molecules show suitable drug and lead properties. They are synthesized and tested in vitro for anticancer activity on MCF-7 and MDA-MB-231 cell lines. Most of the compounds are more active than predicted and show stronger activity on MCF-7 than on MDA-MB-231. Four of the compounds (1a, 1b, 1c, and 1e) show IC50 values below 1 μM on MCF-7 and one (1e) on MDA-MB-231. The presence of an indole ring bearing 5-Cl, 5-OCH3, or 1-COCH3 has the most pronounced positive effect on the cytotoxic activity of the arylsulfonylhydrazones designed in the present study.

SERDs: a case study in targeted protein degradation

Endocrine therapies for breast cancer target ERα which is found in more than 70% of breast cancers. Unfortunately, endocrine resistance typically occurs, in which case Selective Estrogen Receptor Degraders (SERDs) represent the last line of treatment for metastatic breast cancer patients. Fulvestrant, the only currently approved SERD and one of the first targeted protein degradation therapies, presents poor drug-like properties which has led to the development of a new generation of oral SERDs. This review summarizes recent progress in the evolution of SERDs, focusing on clinical candidates and their degradation motifs within the broader context of targeted protein degradation therapies.

Exercise training and detraining effects on body composition, muscle strength and lipid, inflammatory and oxidative markers in breast cancer survivors under tamoxifen treatment

AIMS

The present study aimed to verify the effects of resistance training (RT) and successive detraining on body composition, muscle strength and lipid profile as primary outcome, and the oxidative stress and inflammatory markers as second outcome of postmenopausal Breast Cancer (BC) survivors undergoing tamoxifen (TA).

MAIN METHODS

Fourteen postmenopausal BC survivors underwent 12 weeks of resistance exercise training and subsequently 12 weeks of detraining. Anthropometric parameters, lipid profile, muscle strength, inflammatory cytokines and the oxidative stress markers, were assessed before, after the training period and after detraining period.

KEY FINDINGS

One-way ANOVA showed that fat mass decrease (39.4 ± 6.9 to 37.7 ± 6.8%) and free-fat mass increase (39.3 ± 4.9 to 40.3 ± 5.6%) after RT. Muscle strength increased in response to training but decreased after the detraining period. Triglycerides (156 ± 45 to 123 ± 43 mg/dL) and total cholesterol (202 ± 13 to 186 ± 16 mg/dL) decreased after the RT and HDL-cholesterol (47 ± 9 to 56 ± 9 mg/dL) increased after RT and remained higher (53 ± 10 mg/dL) than after detraining. IL-6 increases (24.65 ± 10.85 to 41.42 ± 22.88 pg/mL) and IL-17 (2.42 ± 0.32 to 1.69 ± 0.19 pg/mL), TBARS (1.91 ± 0.19 to 1.03 ± 0.1 μmol/L), SOD (24.65 ± 10.85 to 41.42 ± 22.88 U/gHb) and Catalase activity (445.9 ± 113.0 to 345.8 ± 81.7 k/gHb·s) reduced after RT and remained lower after detraining.

SIGNIFICANCE

Resistance exercise training improves health markers of BC survivors undergoing TA and detraining are not sufficient to reverse the positive effects in oxidative stress markers.

Why do Older Women Avoid Breast Cancer Surgery? A Qualitative Analysis of Decision-making Factors

BACKGROUND

Few studies have explored why older women (≥70 years old) avoid breast cancer surgery. This study aimed to identify physician- and patient-perceived attitudes that influence the decision to avoid surgery among older women with invasive breast cancer.

METHODS

Semi-structured in-depth interviews were conducted with multidisciplinary breast cancer specialists and older women (≥70 years old) with breast cancer who declined surgery. Transcripts were iteratively coded using a theoretical framework to guide identification of common themes. Thematic comparison was performed between patients and physicians.

RESULTS

Ten breast cancer specialists and eleven patients participated. Physicians believed older women declined surgery because they did not perceive breast cancer as a life-threatening ailment compared to other medical comorbidities. Physicians did not discuss breast reconstruction, as it was perceived to be unimportant. Treatment side effects, length of treatment, impact on quality of life, and minimal survival benefit strongly influenced patients' decision to decline surgery. Patients valued independence and quality of life over quantity of life. Patients felt empowered to participate in the decision-making process but appreciated having support. Both phyisicians and patients had congruent beliefs with respect to age impacting treatment decision, cosmesis playing a minor factor in treatment decisions, and importance of quality of life; however, they were discordant in their perceptions about the amount of support that patients have from their families.

CONCLUSIONS

The decision to avoid surgery in older women stems from a variety of individual beliefs. Acknowledging patient values early in treatment planning may facilitate a patient-centered approach to the decision-making process.

The beneficial androgenic action of steroidal aromatase inactivators in estrogen-dependent breast cancer after failure of nonsteroidal drugs

Direct treatment of ER (+) breast cancer with Formestane diminishes the tumor within weeks. This is unlikely due to lack of estrogens alone. We proposed that it is the negative influence of androgens on the growth of ER(+) breast cancer. We investigated the influence of Formestane and Exemestane and of their major androgenic metabolites 4-hydroxytestosterone and 17-hydroexemestane on the proliferation of MCF-7 cells and ZR-75-1 cells. Inhibitory effects could be prevented by antiandrogens and siRNA. Activation of the AR in MCF-7 and U2-OS cells was tested by reporter gene assays. In vivo androgenicity was evaluated using the Hershberger assay. Influence on the cell cycle was demonstrated by flow-cytometry. Influence of androgens on the activity of CCND1 was demonstrated by Chip-qPCR. Antitumor activity was determined by topical treatment of DMBA tumors. We found that breast cancer cells can metabolize Formestane and Exemestane to androgenic compounds which inhibit proliferation. This can be explained by hindering the accessibility of CCND1 by histone modification. Androgenic metabolites can abolish the growth of DMBA-tumors and prevent the appearance of new tumors. The lack of cross-resistance between steroidal and nonsteroidal aromatase inhibitors is due to inhibitory effects of androgenic steroidal metabolites on the production of cyclin D1. These sterols not only inhibit proliferation of cancer cells but can also stop the growth of DMBA cancers upon direct absorption into the tumor. The quick and considerable effect on ER(+) tumors may open a new avenue for neodjuvant treatment.

Osteoporosis and musculoskeletal complications related to therapy of breast cancer

Aromatase inhibitors (AIs) are the treatment of choice for the majority of postmenopausal women with estrogen receptor (ER) positive breast cancers in early and advanced stage settings. One of most frequent side effects of AIs is bone loss that is of sufficient magnitude to increase risk of osteoporotic fractures. Osteoporosis is primarily a complex genetic disease with few modifiable risk factors. As the lifespan increases, and breast mortality decreases, more women with breast cancer will be at risk of osteoporotic fractures, or falls that result in fractures. The screening, prevention, and treatment of osteoporosis do not differ in women with or without breast cancer. Rather, breast cancer treatments, including AIs, chemotherapy-induced ovarian failure, and gonadotropin-releasing hormone (GnRH) agonists, all decrease estrogen, which causes net bone resorption, leading some women to experience fracture. Occurring in about fifty-percent of women, AI-induced arthralgia is one of the most common side effects, and causes of nonadherence and discontinuation. Registry studies show that nonadherence and discontinuation may contribute to higher breast cancer mortality. Thus, understanding the mechanisms, risk factors, and interventions to mitigate symptoms of AI-induced arthralgia is a high priority.

An update on treatment for post-menopausal metastatic breast cancer in elderly patients

INTRODUCTION

Elderly patients make up a significant proportion of patients with metastatic breast cancer. With several options available in the metastatic setting for hormone positive breast cancer, these patients require an individualized approach to decision-making that considers multiple factors beyond performance status and chronologic age.

AREAS COVERED

The authors review the literature on endocrine monotherapy and combinations for hormone positive metastatic breast cancer, with specific commentary on the efficacy and toxicity for elderly patients. The authors describe the role of comprehensive geriatric assessment (CGA) and highlight the considerations for the use of bone modifying agents, and HER2-targeted therapy for hormone positive/HER2+ patients.

EXPERT OPINION

Evidence for elderly patients is largely based on subgroup analyses, which should be interpreted with caution. Nonetheless, elderly patients with metastatic hormone receptor positive breast cancer appear to derive similar benefit from treatments as younger patients. Similarly, for most drugs, these patients have no significant worsening of toxicity compared to younger patients. In addition to tumor biology, patient values and information from the CGA should be used to guide treatment decisions.

Expression of aromatase in tumor related stroma is associated with human bladder cancer progression

Putative gender differences in bladder cancer (BCa) have been proposed to result from sex hormone influence. Aromatase is the key enzyme catalyzing the conversion of androgens to estrogens which may result in an intratumoral microenviroment with increased estrogen production. In this study, we investigated the expression pattern of aromatase and its association with BCa progression. Tissue samples from 88 BCa patients who underwent cystectomy were obtained. Using immunohistochemistry (IHC), expression of aromatase in tumor epithelium (TE) and tumor related stroma (TS) were evaluated separately, and the association of aromatase expression status with pathologic variables and overall survival (OS) outcome was examined. High aromatase expression was found in 33/88 (37.5%) of TE and in 65/88 (73.9%) of TS. Increased aromatase expression in TE had a trend to correlate with male gender. Increased aromatase in TS was significantly associated with adverse pathologic variables including higher pathologic pT, positive lymph node metastasis (pN), lymphovascular invasion (LVI), and distant metastasis. In univariate analysis, high aromatase expression in TS was significantly associated with poorer overall survival (p = 0.014), but this association was not significant (p = 0.163) in multivariate cox analysis adjusted for independent factors including age at surgery and pN. These results demonstrate that aromatase expression in TS but not TE may play a critical role in BCa progression. Our findings provide direct evidence of aromatase involvement in BCa and suggest endocrine therapy may have a potential role in the treatment of BCa.

An update on first line therapies for metastatic breast cancer

INTRODUCTION

In recent years, outcomes of patients with metastatic breast cancer (MBC) have improved due to a greater understanding of the mechanisms of carcinogenesis in the development of newer molecularly targeted drugs, especially those as a front-line therapy. Remarkable improvements have been made in the treatment of hormone receptor positive (HR+) and Her2 positive MBC and currently targeted treatment strategies represent a valid first line treatment.

AREAS COVERED

Herein, the authors provide an overview of the first-line pharmacotherapies currently available for the treatment of MBC and provide their expert perspectives on the area.

EXPERT OPINION

Decisions on the first-line treatment of MBC should consider the clinical features of the disease, but also the biological mechanisms that regulate tumor cell growth. New and effective therapeutic agents have recently been introduced in the first-line therapy of MBC. However, to optimize the treatment of patients with metastatic disease, clinicians need biomarkers of resistance or sensitivity to targeted therapies. Efforts must also be made in developing strategies to personalize treatments of MBC patients and to identify those patients who might gain the most benefit from new treatment interventions, to save costs and limit toxicity.

Unfavorable effect of calcitriol and its low-calcemic analogs on metastasis of 4T1 mouse mammary gland cancer

Low vitamin D status is considered as a risk factor for breast cancer and has prognostic significance. Furthermore, vitamin D deficiency increases after adjuvant cancer therapy, which alters bone metabolism increasing the risk of osteoporosis. It is now postulated that vitamin D supplementation in breast cancer treatment delays the recurrence of cancer thereby extending survival. We evaluated the impact of calcitriol and its low-calcemic analogs, PRI-2191 and PRI-2205, on the tumor growth, angiogenesis, and metastasis of 4T1 mouse mammary gland cancer. Gene expression analysis related to cancer invasion/metastasis, real-time PCR, ELISA, western blotting, and histochemical studies were performed. In vitro studies were conducted to compare the effects of calcitriol and its analogs on 4T1 and 67NR cell proliferation and expression of selected proteins. Calcitriol and its analogs increased lung metastasis without influencing the growth of primary tumor. The levels of plasma 17β-estradiol and transforming growth factor β (TGFβ) were found to be elevated after treatment. Moreover, the results showed that tumor blood perfusion improved and osteopontin (OPN) levels increased, whereas vascular endothelial growth factor (VEGF) and TGFβ levels decreased in tumors from treated mice. All the studied treatments resulted in increased collagen content in the tumor tissue in the early step of tumor progression, and calcitriol caused an increase in collagen content in lung tissue. In addition, in vitro proliferation of 4T1 tumor cells was not found to be affected by calcitriol or its analogs in contrast to non-metastatic 67NR cells. Calcitriol and its analogs enhanced the metastatic potential of 4T1 mouse mammary gland cancer by inducing the secretion of OPN probably via host cells. In addition, OPN tumor overexpression prevailed over the decreasing tumor TGFβ level and blood vessel normalization via tumor VEGF deprivation induced by calcitriol and its analogs. Moreover, the increased plasma TGFβ and 17β-estradiol levels contributed to the facilitation of metastatic process.

Efficacy and safety of endocrine monotherapy as first-line treatment for hormone-sensitive advanced breast cancer: A network meta-analysis

BACKGROUND

Endocrine therapy was recommended as the preferred first-line treatment for hormone receptor-positive (HR+, i.e., ER+ and/or PgR+), human epidermal growth factor receptor-2-negative (HER2-) postmenopausal advanced breast cancer (ABC), but which endocrine monotherapy is optimal lacks consensus. We aimed to identify the optimal endocrine monotherapy with a network meta-analysis.

METHODS

We performed a network meta-analysis for a comprehensive analysis of 6 first-line endocrine monotherapies (letrozole, anastrozole, exemestane, tamoxifen, fulvestrant 250 mg and 500 mg) for HR+ HER2- metastatic or locally advanced breast cancer in postmenopausal patients. The main outcomes were objective response rate (ORR), time to progression (TTP), and progression-free survival (PFS). Secondary outcomes were adverse events.

RESULTS

We identified 27 articles of 8 randomized controlled trials including 3492 patients in the network meta-analysis. For ORR, the treatments ranked in descending order of effectiveness were letrozole > exemestane > anastrozole > fulvestrant 500 mg > tamoxifen > fulvestrant 250 mg. For TTP/PFS, the order was fulvestrant 500 mg > letrozole > anastrozole > exemestane > tamoxifen > fulvestrant 250 mg. We directly compared adverse events and found that tamoxifen produced more hot flash events than fulvestrant 250 mg.

CONCLUSIONS

Fulvestrant 500 mg and letrozole might be optimal first-line endocrine monotherapy choices for HR+ HER2- ABC because of efficacious ORR and TTP/PFS, with a favorable tolerability profile. However, direct comparisons among endocrine monotherapies in the first-line therapy setting are still required to robustly demonstrate any differences among these endocrine agents. Clinical choices should also depend on the specific disease situation and duration of endocrine therapy.

Prevalence of aromatase inhibitor-induced arthralgia in breast cancer: a systematic review and meta-analysis

BACKGROUND

Although aromatase inhibitors have proven to be an effective treatment of hormone receptor-positive breast cancer in postmenopausal women, aromatase inhibitor-induced arthralgia (AIA) is an adverse event associated with low compliance with treatment. The aim of this literature study is to assess the prevalence of AIA and to provide an overview of significant predictors for the development of AIA.

METHODS

A systematic review was conducted using PubMed, Cochrane Library and Web of Science. A meta-analysis was performed and heterogeneity has been investigated by moderator analyses. The meta-analysis was repeated with studies that were considered as best evidence, i.e. studies with an above-average score on the STROBE checklist.

RESULTS

Twenty-one studies (13,177 participants) were included. Prevalence rates ranged from 0.200 to 0.737. Meta-analysis resulted in a pooled estimate of 0.459 (95% CI = [0.397-0.520) with a high heterogeneity (I ² = 98%). Moderator analysis showed no differences regarding heterogeneity. Predictors for the development of AIA included a body mass index of 25-30 kg/m² (OR = 0.33), taxane-based chemotherapy (OR = 4.08), stage III cancer (OR = 0.32) and a duration of menopause of 5-10 years (OR = 1.10) or >10 years (OR = 0.44-3.29) (An OR <1 indicates a predictor of lower risk of AIA).

DISCUSSION

Despite the established benefits of AI, an important portion of the patients experiences AIA. More research is needed to investigate the efficacy of treatments such as exercise therapy for AIA.

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.

Late recurrence of breast carcinoma metastasis to the hypopharynx: a case report

Background

We report a rare case of a patient with a hypopharyngeal metastasis from breast cancer.

Case presentation

Isolated breast cancer metastasis to the hypopharynx has been previously reported in only one autopsy case. Herein, we report a 56-year-old woman with metastases to the hypopharynx almost 24 years after receiving a mastectomy and chemotherapy to treat primary breast carcinoma. We believe that she is the first patient to be treated for metastatic breast carcinoma to the hypopharynx. The hypopharyngeal tumor reduced in size after administration of an oral aromatase inhibitor. The patient has remained alive with a preserved larynx for three years.

Conclusions

Breast cancer metastasis to the hypopharynx is an extremely rare event.

Delaying Chemotherapy in the Treatment of Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer

Global guidelines for the management of locally advanced or metastatic hormone receptor-positive (HR-positive), human epidermal growth factor 2-negative (HER2-negative) breast cancer recommend endocrine therapy as first-line treatment for all patients, regardless of age or postmenopausal status. However, current practice patterns in the United States and Europe suggest that these modes of therapy are not being used as recommended, and many patients with advanced HR-positive, HER2-negative disease are being treated first-line with chemotherapy or switched to chemotherapy after a single endocrine therapy. Given that chemotherapy is associated with increased toxicity and reduced quality of life (QOL) compared with endocrine therapy, prolonging the duration of response obtained with endocrine therapy may help delay chemotherapy and its attendant toxicities. Several strategies to delay or overcome endocrine resistance and thereby postpone chemotherapy have been explored, including the use of second-line endocrine agents with different mechanisms of action, adding targeted agents that inhibit specific resistance pathways, and adding agents that act in complementary or synergistic ways to inhibit tumor cell proliferation. This review analyzes the different therapy options available to HR-positive, HER2-negative patients with advanced breast cancer that can be used to delay chemotherapy and enhance QOL.

Predictive markers in elderly patients with estrogen receptor-positive breast cancer treated with aromatase inhibitors: an array-based pharmacogenetic study

So far, no reliable predictive clinicopathological markers of response to aromatase inhibitors (AIs) have been identified, and little is known regarding the role played by host genetics. To identify constitutive predictive markers, an array-based association study was performed in a cohort of 55 elderly hormone-dependent breast cancer (BC) patients treated with third-generation AIs. The array used in this study interrogates variants in 225 drug metabolism and disposition genes with documented functional significance. Six variants emerged as associated with response to AIs: three located in ABCG1, UGT2A1, SLCO3A1 with a good response, two in SLCO3A1 and one in ABCC4 with a poor response. Variants in the AI target CYP19A1 resulted associated with a favourable response only as haplotype; haplotypes with increased response association were also detected for ABCG1 and SLCO3A1. These results highlight the relevance of host genetics in the response to AIs and represent a first step toward precision medicine for elderly BC patients.

Medication use by early-stage breast cancer survivors: a 1-year longitudinal study

Purpose

The aim of this study is to characterize the patterns of medication use by early-stage breast cancer (ESBC) survivors from diagnosis to 1 year post-chemotherapy.

Methods

A single-center longitudinal study was conducted with ESBC patients diagnosed between December 2011 and June 2014. Data on the medication use of individual patients were retrieved from prescription databases, supplemented by records from the National Electronic Health Records. The data covered the period from ESBC diagnosis to 1 year post-chemotherapy. Medication types were classified according to the World Health Organization’s Anatomical Therapeutic Chemical classification system, and medication for chronic diseases was created by adapting a list of 20 chronic diseases provided by the U.S. Department of Human and Health Services.

Results

Of the 107 patients involved in the study (mean age 51.1 ± 8.4 years; 78.5 % Chinese), 46.7 % manifested non-cancer comorbidities, of which hypertension (24.3 %) was the most prevalent, followed by hyperlipidemia (13.1 %) and diabetes (5.6 %). Calcium channel blockers (12.1 %) and lipid-modifying agents (11.2 %) were the most common chronic medication types used before chemotherapy, and their use persisted during chemotherapy (10.3 and 11.2 %, respectively) and after chemotherapy (11.2 and 13.1 %, respectively). Hormonal therapy was the predominant post-chemotherapy medication (77.6 %). A statistically significant increase (p < 0.0001) was observed in the mean number of chronic disease medication classes prescribed to patients between the pre-chemotherapy (0.53 ± 1.04) and chemotherapy (0.62 ± 1.08) periods and between the chemotherapy and post-chemotherapy (1.63 ± 1.35) periods.

Conclusions

There is an increase in trend of chronic medication usage in breast cancer survivors after cancer treatment. This study provides important insights into the design of medication management programs tailored to this population. Future studies should incorporate a control population to improve the interpretation of study results.

The changing face of a rare disease: lymphangioleiomyomatosis

Lymphangioleiomyomatosis is a rare disease characterised by cystic destruction of the lung, lymphatic abnormalities and abdominal tumours. It affects almost exclusively females and can occur sporadically or in patients with tuberous sclerosis complex. In the past decade remarkable progress has been made in understanding of the pathogenesis of this disease leading to a new therapeutic approach. This review summarises recent advances regarding pathogenic mechanisms and clinical manifestations, and highlights the current and the most promising future therapeutic strategies.

Current medical treatment of estrogen receptor-positive breast cancer

Approximately 80% of breast cancers (BC) are estrogen receptor (ER)-positive and thus endocrine therapy (ET) should be considered complementary to surgery in the majority of patients. The advantages of oophorectomy, adrenalectomy and hypophysectomy in women with advanced BC have been demonstrated many years ago, and currently ET consist of (1) ovarian function suppression (OFS), usually obtained using gonadotropin-releasing hormone agonists (GnRHa); (2) selective estrogen receptor modulators or down-regulators (SERMs or SERDs); and (3) aromatase inhibitors (AIs), or a combination of two or more drugs. For patients aged less than 50 years and ER+ BC, there is no conclusive evidence that the combination of OFS and SERMs (i.e., tamoxifen) or chemotherapy is superior to OFS alone. Tamoxifen users exhibit a reduced risk of BC, both invasive and in situ, especially during the first 5 years of therapy, and extending the treatment to 10 years further reduced the risk of recurrences. SERDs (i.e., fulvestrant) are especially useful in the neoadjuvant treatment of advanced BC, alone or in combination with either cytotoxic agents or AIs. There are two types of AIs: type I are permanent steroidal inhibitors of aromatase, while type II are reversible nonsteroidal inhibitors. Several studies demonstrated the superiority of the third-generation AIs (i.e., anastrozole and letrozole) compared with tamoxifen, and adjuvant therapy with AIs reduces the recurrence risk especially in patients with advanced BC. Unfortunately, some cancers are or became ET-resistant, and thus other drugs have been suggested in combination with SERMs or AIs, including cyclin-dependent kinase 4/6 inhibitors (palbociclib) and mammalian target of rapamycin (mTOR) inhibitors, such as everolimus. Further studies are required to confirm their real usefulness.

Treating Elderly Patients With Hormone Receptor-Positive Advanced Breast Cancer

As the overall population ages, the proportion of elderly patients (aged ≥65 years) with breast cancer also increases. Studies have shown that elderly patients with hormone receptor–positive breast cancer can derive as much benefit from treatment as do younger patients, yet they remain underrepresented in clinical trials and are often undertreated in clinical practice. Treatment decisions for older patients should not be based solely on chronologic age; a patient’s physiologic functioning and comorbidities must also be taken into consideration. For recurrent or metastatic disease, systemic treatment with endocrine therapies or chemotherapy may prolong a patient’s life and alleviate troublesome symptoms. Resistance to therapy remains a problem in the advanced breast cancer setting, with most patients eventually becoming resistant to additional treatment. New combination regimens that target multiple pathways, such as everolimus plus exemestane, have shown efficacy in elderly patients previously resistant to endocrine therapies, and future research may need to focus on such combinations in order to improve outcomes in this patient group. A number of investigational agents are in clinical development, although few studies identify their effects in the elderly patient population. Optimizing effective yet tolerable therapeutic regimens for elderly patients could improve their outcomes while ensuring that the goals of improved survival and quality of life are considered.

Clinical utility of exemestane in the treatment of breast cancer

Breast cancer is the most prevalent cancer in women, causing a significant mortality worldwide. Different endocrine strategies are available for the treatment of hormone-sensitive breast cancer, including antiestrogen tamoxifen and fulvestrant, as well as third-generation aromatase inhibitors (AIs), such as letrozole, anastrozole, and exemestane. In this review, we will focus on exemestane, its clinical use, and its side effects. Exemestane is a steroidal third-generation AI now used in all treatment settings for breast cancer. In the metastatic disease, it has been extensively investigated as the first-, second-, and further-line treatment and it is now registered for the treatment of postmenopausal women with advanced estrogen-receptor-positive breast cancer whose disease has progressed following antiestrogen therapy. A potential lack of cross-resistance with nonsteroidal AIs has been described, giving additional therapeutic opportunities in sequences of endocrine agents. Exemestane is also approved for the adjuvant treatment of postmenopausal early breast cancer, either as upfront monotherapy for 5 years, as a switch following 2–3 years of tamoxifen, or as extended therapy beyond 5 years of adjuvant treatment. New promising data also showed a beneficial effect in young premenopausal early breast cancer patients, when administered together with ovarian suppression. Interesting results have also emerged when exemestane has been investigated as neodjuvant treatment as well as preventive agent in healthy women at high risk for breast cancer. Exemestane is generally well tolerated, with a side effect profile similar to that of other AIs, including menopausal symptoms, arthralgia, and bone loss. In conclusion, exemestane can be considered an effective and well-tolerated endocrine treatment option for all stages of breast cancer.

Comprehensive Geriatric Assessment and predicted 3-year survival in treatment planning for frail patients with early breast cancer

BACKGROUND

Endocrine therapy alone has been a popular treatment for oestrogen receptor-positive breast cancer in elderly patients, although it may be inadequate in those surviving more than 2-3 years. The aim of this study was to estimate 3-year survival in frail patients with early breast cancer, to inform treatment decisions.

METHODS

A risk score was created to estimate 3-year survival in individual patients using data from patients who had Comprehensive Geriatric Assessment (CGA) in a specialist clinic before decisions about their breast cancer treatment were made. The data were analysed using logistic regression.

RESULTS

Ninety-seven (29·6 per cent) of the 328 patients had died by 3 years. Four components of the assessment proved strongly associated with survival: Mini Mental State Examination, Barthel Index of Activities of Daily Living, instrumental Activities of Daily Living and American Association of Anesthesiologists fitness grade. The derived CGA risk score gave an adequate level of discrimination and calibration, with an area under the receiver operating characteristic (ROC) curve of 0·75 (95 per cent c.i. 0·67 to 0·82) (Hosmer-Lemeshow statistic χ(2)  = 7·9, P = 0·448).

CONCLUSION

Detailed assessment can allow prediction of survival probability in frail elderly patients. Good scores indicate good survival prospects and a likely benefit from surgery; poor scores are associated with reduced survival, although with wide variation. CGA is recommended before making decisions on best treatment.

A comparison of letrozole and anastrozole followed by letrozole in breast cancer patients

Background

We previously studied the noninferiority of anastrozole (ANZ) versus ANZ followed by letrozole (A-LTZ) due to reimbursement policy. We found that patients with A-LTZ had better overall survival (OS) than did patients with ANZ alone. This study aimed to prove that patients with A-LTZ also had better OS than patients with letrozole (LTZ) alone.

Methods

All medical records of the breast cancer patients taking LTZ with or without ANZ between 2004 and 2013 were reviewed. All patients were divided into two groups: the LTZ group included patients treated with LTZ alone, and the A-LTZ group included patients treated with ANZ who were automatically changed to LTZ due to change of the reimbursement policy.

Results

From 359 cases, there were 179 cases in the LTZ group and 180 cases in the A-LTZ group. The mean age of patients in the LTZ group was 53.7 years and in the A-LTZ group was 54.2 years. The distribution of clinical stages among the LTZ group versus the A-LTZ group was 21 versus 4 (stage 1), 86 versus 116 (stage 2), 55 versus 46 (stage 3), and 17 versus 14 (stage 4), respectively. Among the LTZ patients, 63.7% took aromatase inhibitor monotherapy and 36.3% had a switching strategy, while in the A-LTZ group, 53.9% took AI monotherapy and 46.1% had a switching strategy. OS of the A-LTZ group was longer than that of the LTZ group.

Conclusion

The patients in A-LTZ, taking ANZ followed by LTZ had better OS than those in LTZ, taking LTZ alone.

Ghrelin and des-acyl ghrelin inhibit aromatase expression and activity in human adipose stromal cells: suppression of cAMP as a possible mechanism

Aromatase converts androgens into estrogens and its expression within adipose stromal cells (ASCs) is believed to be the major driver of estrogen-dependent cancers in older women. Ghrelin is a gut-hormone that is involved in the regulation of appetite and known to bind to and activate the cognate ghrelin receptor, GHSR1a. The unacylated form of ghrelin, des-acyl ghrelin, binds weakly to GHSR1a but has been shown to play an important role in regulating a number of physiological processes. The aim of this study was to determine the effect of ghrelin and des-acyl ghrelin on aromatase in primary human ASCs. Primary human ASCs were isolated from adipose tissue of women undergoing cosmetic surgery. Real-time PCR and tritiated water-release assays were performed to examine the effect of treatment on aromatase transcript expression and aromatase activity, respectively. Treatments included ghrelin, des-acyl ghrelin, obestatin, and capromorelin (GHSR1a agonist). GHSR1a protein expression was assessed by Western blot and effects of treatment on Ca(2+) and cAMP second messenger systems were examined using the Flexstation assay and the Lance Ultra cAMP kit, respectively. Results demonstrate that pM concentrations of ghrelin and des-acyl ghrelin inhibit aromatase transcript expression and activity in ASCs under basal conditions and in PGE2-stimulated cells. Moreover, the effects of ghrelin and des-acyl ghrelin are mediated via effects on aromatase promoter PII-specific transcripts. Neither the GHSR1a-specific agonist capromorelin nor obestatin had any effect on aromatase transcript expression or activity. Moreover, GHSR1a protein was undetectable by Western blot and neither ghrelin nor capromorelin elicited a calcium response in ASCs. Finally, ghrelin caused a significant decrease in basal and forskolin-stimulated cAMP in ASC. These findings suggest that ghrelin acts at alternate receptors in ASCs by decreasing intracellular cAMP levels. Ghrelin mimetics may be useful in the treatment of estrogen-dependent breast cancer.

Considerations for payers in managing hormone receptor-positive advanced breast cancer

Breast cancer (BC) is the second most common cause of death in women. In 2010, the direct cost associated with BC care in the US was $16.5 billion, the highest among all cancers. By the year 2020, at the current rates of incidence and survival, the cost is projected to increase to approximately $20 billion. Although endocrine therapies to manage hormone receptor-positive (HR+) BC are highly effective, endocrine resistance results in disease progression. Increased understanding of endocrine resistance and the mechanisms of disease progression has led to development and subsequent approval of novel targeted treatments, resulting in the expansion of the therapeutic armamentarium to combat HR+ BC. Clear guidelines based on the safety and efficacy of treatment options exist; however, the optimal sequence of therapy is unknown, and providers, payers, and other key players in the health care system are tasked with identifying cost-effective and evidence-based treatment strategies that will improve patient outcomes and, in time, help curb the staggering increase in cost associated with BC care. Safety and efficacy are key considerations, but there is also a need to consider the impact of a given therapy on patient quality of life, treatment adherence, and productivity. To minimize cost associated with overall management, cost-effectiveness, and financial burden that the therapy can impose on patients, caregivers and managed care plans are also important considerations. To help evaluate and identify the optimal choice of therapy for patients with HR+ advanced BC, the available data on endocrine therapies and novel agents are discussed, specifically with respect to the safety, efficacy, financial impact on patients and the managed care plan, impact on quality of life and productivity of patients, and improvement in patient medication adherence.

Managing postmenopausal women with hormone receptor-positive advanced breast cancer who progress on endocrine therapies with inhibitors of the PI3K pathway

Although endocrine therapies that interfere with estrogen receptor (ER)-mediated signaling have revolutionized the management of postmenopausal women with hormone receptor-positive (HR+) breast cancer (BC), long-term management of these patients is suboptimal because of the eventual emergence of endocrine resistance. Intense research has elucidated a number of targets that act downstream or upstream of the ER, as well as those that crosstalk with the ER; however, clinical validation of inhibiting specific targets to overcome endocrine resistance has been lacking. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway has been implicated to mediate endocrine resistance, and a number of novel agents that target this pathway are in early- and late-stage clinical trials. Recently, everolimus, an inhibitor of mTOR, a critical component of the PI3K/AKT/mTOR pathway, in combination with endocrine therapy, was shown to prolong progression-free survival with a manageable adverse-event profile in postmenopausal patients with HR+ BC. Bolstered by the safety and efficacy observed with concomitant inhibition of the ER and the PI3K/mTOR pathway and the validation of dual inhibition approach in managing postmenopausal patients with HR+ BC, a number of novel agents that inhibit PI3K (pan-PI3K inhibitors) or PI3K and mTOR (dual PI3K/mTOR) are being evaluated in clinical trials. Thus, mTOR inhibitors have provided the much-needed ammunition to oncologists who manage postmenopausal women with BC and have paved the way for the development of novel therapies that target the PI3K/mTOR pathway. Use of these novel therapies in managing postmenopausal women with BC, in combination with endocrine therapies, is expected to improve overall outcomes by overcoming endocrine resistance.

Aromatase inhibitors in the breast cancer clinic: focus on exemestane

Breast cancer is the most prevalent type of cancer in women and responsible for significant female cancer-related mortality worldwide. In the Western world, over 80% of breast cancers are hormone-receptor positive for which endocrine therapy is administered. The main anti-estrogen treatments in use consist of selective estrogen-receptor modulators, such as tamoxifen, and third-generation aromatase inhibitors (AIs), such as exemestane, letrozole, and anastrozole. In this review, the focus will lie on exemestane, its clinical use, and its side-effect profile. Exemestane is the only third-generation steroidal AI. Its efficacy as a first-line treatment in metastatic breast cancer has been demonstrated. Therefore, exemestane could be considered a valid first-line therapeutic option, but it also can be used in second-line or further situations. Exemestane is mostly used as part of sequential adjuvant treatment following tamoxifen, but in this setting it is also active in monotherapy. Furthermore, this AI has been studied in the neoadjuvant setting as presurgical treatment, and even as chemoprevention in high-risk healthy postmenopausal women. It may reverse side effects of tamoxifen, such as endometrial changes and thromboembolic disease but may also cause some inconvenient side effects itself. Additionally, there is a lack of total cross-resistance between exemestane and nonsteroidal AIs as far as their anti-tumoral efficacy is concerned; moreover the two classes of AIs display a nontotal overlapping toxicity profile. Taking together, exemestane can be considered as a useful treatment option at all stages of breast cancer.

A UK national survey of breast surgeons on primary endocrine therapy of early operable breast cancer

INTRODUCTION

A significant proportion of elderly breast cancer patients in the UK have no surgical treatment recorded and appear to be treated with primary endocrine therapy (PET) only. Despite this, PET remains one of the poorly studied areas in breast cancer therapy and very little is known about the practice of PET in the UK.

METHODS

A questionnaire comprising 14 questions relevant to PET was sent to 489 breast surgeons who were members of the UK Association of Breast Surgery and returned questionnaires were analysed.

RESULTS

Overall, 228 questionnaires (47%) were returned. The vast majority (93%) of surgeons who responded use PET in early operable breast cancer in elderly women unfit for surgery or owing to patient preference but 7% would recommend PET to fit elderly patients. Most (76%) use letrozole. The percentage of elderly patients treated with PET varied from <10% to 70% between surgeons. The majority (77%) of respondents had not formally audited the outcome of their PET patients and over 70% underestimated the expected survival of an 80-year-old woman.

CONCLUSIONS

Most UK breast surgeons use PET in elderly patients with surgically resectable breast cancer. While most use it in unfit, frail patients, a minority would treat even fit elderly women with PET. Most surgeons have not formally audited the outcome of their patients treated with PET and underestimate the expected survival of elderly patients, which might have an impact on their decision to offer PET rather than surgery.

Synergistic effects of exemestane and aspirin on MCF-7 human breast cancer cells

OBJECTIVE

The purpose of this study is to investigate the combined effects of exemestane and aspirin on MCF-7 human breast cancer cells.

METHODS

Antiproliferative effects of exemestane and aspirin, alone and in combination, on growth of MCF-7 human breast cancer cells were assessed using the MTT assay. Synergistic interaction between the two drugs was evaluated in vitro using the combination index (CI) method. The cell cycle distribution was analyzed by flow cytometry and Western blotting was used to investigate the expression of cyclooxygenase-1, cyclooxygenase-2 and Bcl-2.

RESULTS

MTT assays indicated that combination treatment obviously decreased the viability of MCF-7 human breast cancer cells compared to individual drug treatment (CI<1). In addition, the combination of exemestane and aspirin exhibited a synergistic inhibition of cell proliferation, significantly arrested the cell cycle in the G0/G1 phase and produced a stronger inhibitory effect on COX-1 and Bcl-2 expression than control or individual drug treatment.

CONCLUSION

These results indicate that the combination of exemestane and aspirin might become a useful method to the treatment of hormone- dependent breast cancer. The combination of the two inhibitors significantly increased the response as compared to single agent treatment, suggesting that combination treatment could become a highly effective approach for breast cancer.

Validation of a proxy for estrogen receptor status in breast cancer patients using dispensing data

AIM

To assess the performance of a proxy for estrogen receptor (ER) status in breast cancer patients using dispensing data.

METHODS

We derived our proxy using 167 patients. ER+ patients had evidence of at least one dispensing record for hormone therapy during the lookback period, irrespective of diagnosis date and ER- had no dispensing records for hormone therapy during the period. We validated the proxy against our gold standard, ER status from pathology reports or medical records. We assessed the proxy's performance using three lookback periods: 4.5 years, 2 years, 1 year.

RESULTS

More than half of our cohort (62%) were >50 years, 54% had stage III/IV breast cancer at recruitment, (46%) were diagnosed with breast cancer in 2009 and 23% were diagnosed before 2006. Sensitivity and specificity were high for the 4.5 year lookback period (93%, 95% CI: 86-96%; and 95%: 83-99%), respectively) and remained high for the 2-year lookback period (91%: 84-95%; and 95%: 83-99%). Sensitivity decreased (83%: 75.2-89%) but specificity remained high (95%: 83-99%) using the 1-year lookback period and the period is long enough to allow sufficient time for hormone therapy to be dispensed.

CONCLUSION

Our proxy accurately infers ER status in studies of breast cancer treatment based on secondary health data. The proxy is most robust with a minimum lookback period of 2 years.

The potential therapeutic benefits of vitamin D in the treatment of estrogen receptor positive breast cancer

Calcitriol (1,25-dihydroxyvitamin D(3)), the hormonally active form of vitamin D, inhibits the growth of many malignant cells including breast cancer (BCa) cells. The mechanisms of calcitriol anticancer actions include cell cycle arrest, stimulation of apoptosis and inhibition of invasion, metastasis and angiogenesis. In addition we have discovered new pathways of calcitriol action that are especially relevant in inhibiting the growth of estrogen receptor positive (ER+) BCa cells. Calcitriol suppresses COX-2 expression and increases that of 15-PGDH thereby reducing the levels of inflammatory prostaglandins (PGs). Our in vitro and in vivo studies show that calcitriol decreases the expression of aromatase, the enzyme that catalyzes estrogen synthesis selectively in BCa cells and in the mammary adipose tissue surrounding BCa, by a direct repression of aromatase transcription via promoter II as well as an indirect effect due to the reduction in the levels of PGs, which are major stimulator of aromatase transcription through promoter II. Calcitriol down-regulates the expression of ERα and thereby attenuates estrogen signaling in BCa cells including the proliferative stimulus provided by estrogens. Thus the inhibition of estrogen synthesis and signaling by calcitriol and its anti-inflammatory actions will play an important role in inhibiting ER+BCa. We hypothesize that dietary vitamin D would exhibit similar anticancer activity due to the presence of the enzyme 25-hydroxyvitamin D-1α-hydroxylase (CYP27B1) in breast cells ensuring conversion of circulating 25-hydroxyvitamin D to calcitriol locally within the breast micro-environment where it can act in a paracrine manner to inhibit BCa growth. Cell culture and in vivo data in mice strongly suggest that calcitriol and dietary vitamin D would play a beneficial role in the prevention and/or treatment of ER+BCa in women.

Optimizing treatments for lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM), a multisystem disease predominantly affecting premenopausal women, is associated with cystic lung destruction and lymphatic and kidney tumors. LAM results from the proliferation of a neoplastic cell that has mutations in the tuberous sclerosis complex 1 or 2 genes, leading to activation of a critical regulatory protein, mammalian target of rapamycin. In this report, we discuss the molecular mechanisms regulating LAM cell growth and report the results of therapeutic trials employing new targeted agents. At present, inhibitors of mammalian target of rapamycin such as sirolimus appear to be the most promising therapeutic agents, although drug toxicity and development of resistance are potential problems. As the pathogenesis of LAM is being further recognized, other therapeutic agents such as matrix metalloproteinase inhibitors, statins, interferon, VEGF inhibitors, chloroquine analogs and cyclin-dependent kinase inhibitors, along with sirolimus or a combination of several of these agents, may offer the best hope for effective therapy.

Complete response to exemestane in a patient with a desmoid tumor

Desmoid tumors are rare mesenchymal neoplasms without metastatic potential. Despite the benign nature of this condition, some patients develop disease progression despite all locoregional options for care. Aggressive forms of desmoid tumors may induce morbidity that can lead to physical impairment and mortality that is occasionally observed as a result of local infiltrative growth and tissue invasion, in particular with abdominal disease. Few therapeutic options are available for patients with recurrent/unresectable desmoid tumors. Several studies have suggested the potential benefit of antiestrogens such as tamoxifen in this setting. Here we report the first description of the efficacy of an aromatase inhibitor in a patient with a desmoid tumor.