Celecoxib anti-aromatase neoadjuvant (CAAN) trial for locally advanced breast cancer

Role of imaging based response assesment for adapting neoadjuvant systemic therapy for breast cancer: A systematic review

PURPOSE

The objective of this systematic review is to investigate the role of imaging in response monitoring during neoadjuvant systemic therapy (NST) for breast cancer and assess whether treatment modifications based on imaging response are implemented in clinical practice.

METHODS

A systematic review was conducted, analyzing five clinical practice guidelines and 147 clinical trial publications involving NST for breast cancer. The snowballing technique was employed, using a "start set" of clinical guidelines to trace relevant trials. Additionally, a PubMed search was conducted to identify trials published between 2023-2024. The review analyzed the use of imaging modalities, timing, and response criteria, and whether escalation, de-escalation, or change of treatment occurred based on imaging response.

RESULTS

Imaging was utilized in 81 % (119/147) of the trials, with ultrasound, MRI, and mammography being the most frequently employed modalities. Mid-treatment imaging was applied in 56 % (83/147) of the trials. However, only 15 % (22/147) of the trials implemented treatment modifications based on imaging response, highlighting the limited application of imaging response-guided therapy. No standardized imaging protocols or consistent response-guided treatment strategies were identified across the trials or clinical practice guidelines, with considerable variability in imaging methods, timing, and response criteria.

CONCLUSION

This systematic review underscores the critical need for standardized imaging protocols, response assessment criteria and image-guided treatment decisions. It is therefore evident that imaging for response monitoring during treatment should preferably be performed within clinical trials.

The Efficacy and Safety of Celecoxib in Addition to Standard Cancer Therapy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The purpose of this meta-analysis was to evaluate the efficacy and safety of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, in addition to standard anticancer therapy. Randomized controlled trials (RCTs) that evaluated the efficacy and safety of celecoxib-combined cancer therapy were systematically searched in PubMed and Embase databases. The endpoints were overall survival (OS), progression-free survival (PFS), disease-free survival (DFS), objective response rate (ORR), disease control rate (DCR), pathological complete response (pCR), and adverse events (AEs). The results of 30 RCTs containing 9655 patients showed limited benefits in celecoxib-combined cancer therapy. However, celecoxib-combined palliative therapy prolonged PFS in epidermal growth factor receptor (EGFR) wild-type patients (HR = 0.57, 95%CI = 0.35–0.94). Moreover, despite a slight increase in thrombocytopenia (RR = 1.35, 95%CI = 1.08–1.69), there was no increase in other toxicities. Celecoxib combined with adjuvant therapy indicated a better OS (HR = 0.850, 95%CI = 0.725–0.996). Furthermore, celecoxib plus neoadjuvant therapy improved the ORR in standard cancer therapy, especially neoadjuvant therapy (overall: RR = 1.13, 95%CI = 1.03–1.23; neoadjuvant therapy: RR = 1.25, 95%CI = 1.09–1.44), but not pCR. Our study indicated that adding celecoxib to palliative therapy prolongs the PFS of EGFR wild-type patients, with good safety profiles. Celecoxib combined with adjuvant therapy prolongs OS, and celecoxib plus neoadjuvant therapy improves the ORR. Thus, celecoxib-combined cancer therapy may be a promising therapy strategy.

Neoadjuvant Therapy of Cyclin-Dependent Kinase 4/6 Inhibitors Combined with Endocrine Therapy in HR+/HER2- Breast Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Cyclin-dependent kinase (CDK) 4/6 inhibitors have been advocated for adjuvant therapy of metastatic hormone receptor (HR)+/human epidermal growth factor receptor 2 (HER2)- breast cancer (BC). However, the efficiency of adding CDK 4/6 inhibitors to neoadjuvant therapy was not unequivocal.

OBJECTIVE

The aim of the study was to evaluate the efficiency and toxicity of neoadjuvant CDK 4/6 inhibitors + endocrine therapy (ET) versus neoadjuvant endocrine monotherapy or standard neoadjuvant chemotherapy in HR+/HER2- BC.

METHOD

We searched PubMed, the Cochrane Library, Web of Science, and Embase online databases for randomized controlled trials and single-arm studies written in English until April 2021.

RESULTS

Five studies comparing CDK 4/6 inhibitors + ET as neoadjuvant treatments to ET alone and 2 studies comparing neoadjuvant CDK 4/6 inhibitors + ET to neoadjuvant chemotherapy were analysed. Neoadjuvant CDK 4/6 inhibitors + ET improved the rate of complete cell cycle arrest (CCCA: central Ki67 < 2.7%, odds ratio [OR] = 7.91, 95% confidence interval [CI] = 4.81-13.03, p < 0.001), increased the risk of adverse events (AEs; especially ≥3 AEs; AEs of all grades: OR = 9.10, 95% CI = 2.39-34.58, p = 0.001; AEs ≥3: OR = 12.24, 95% CI = 4.17-35.88, p < 0.001), led to no significant differences in pathological complete response (pCR) in patients with BC (OR = 0.34, 95% CI = 0.04-2.85, p = 0.318) compared to endocrine monotherapy. Moreover, subgroup analysis showed that the 3 types of CDK 4/6 inhibitors all improved the rate of CCCA (ribociclib: OR = 10.31, 95% CI = 3.59-29.61, p < 0.001; palbociclib: OR = 7.39, 95% CI = 1.26-43.40, p = 0.027, and abemaciclib: OR = 8.28, 95% CI = 3.41-20.11, p < 0.001). Compared to neoadjuvant chemotherapy, neoadjuvant CDK 4/6 inhibitors plus ET decreased the risk of AEs ≥3 (OR = 0.50, 95% CI = 0.29-0.87, p = 0.015) and showed similar ability to reach pCR (OR = 0.50, 95% CI = 0.12-2.07, p = 0.342) and reduce the residual cancer burden (RCB, RCB 0-1: OR = 0.47, 95% CI = 0.18-1.22, p = 0.121; RCB 2-3: OR = 2.30, 95% CI = 0.89-5.91, p = 0.084).

CONCLUSIONS

The results suggested that combination therapy had increased efficacy and toxicity compared to endocrine monotherapy and showed similar efficacy to and better safety than neoadjuvant chemotherapy.

Identification of MFGE8 and KLK5/7 as mediators of breast tumorigenesis and resistance to COX-2 inhibition

BACKGROUND

Cyclooxygenase 2 (COX-2) promotes stemness in triple negative breast cancer (TNBC), highlighting COX-2 as a promising therapeutic target in these tumors. However, to date, clinical trials using COX-2 inhibitors in breast cancer only showed variable patient responses with no clear significant clinical benefits, suggesting underlying molecular mechanisms contributing to resistance to COX-2 inhibitors.

METHODS

By combining in silico analysis of human breast cancer RNA-seq data with interrogation of public patient databases and their associated transcriptomic, genomic, and clinical profiles, we identified COX-2 associated genes whose expression correlate with aggressive TNBC features and resistance to COX-2 inhibitors. We then assessed their individual contributions to TNBC metastasis and resistance to COX-2 inhibitors, using CRISPR gene knockout approaches in both in vitro and in vivo preclinical models of TNBC.

RESULTS

We identified multiple COX-2 associated genes (TPM4, RGS2, LAMC2, SERPINB5, KLK7, MFGE8, KLK5, ID4, RBP1, SLC2A1) that regulate tumor lung colonization in TNBC. Furthermore, we found that silencing MFGE8 and KLK5/7 gene expression in TNBC cells markedly restored sensitivity to COX-2 selective inhibitor both in vitro and in vivo.

CONCLUSIONS

Together, our study supports the establishment and use of novel COX-2 inhibitor-based combination therapies as future strategies for TNBC treatment.

Prostaglandin E2 and Cancer: Insight into Tumor Progression and Immunity

The involvement of inflammation in cancer progression has been the subject of research for many years. Inflammatory milieu and immune response are associated with cancer progression and recurrence. In different types of tumors, growth and metastatic phenotype characterized by the epithelial mesenchymal transition (EMT) process, stemness, and angiogenesis, are increasingly associated with intrinsic or extrinsic inflammation. Among the inflammatory mediators, prostaglandin E2 (PGE2) supports epithelial tumor aggressiveness by several mechanisms, including growth promotion, escape from apoptosis, transactivation of tyrosine kinase growth factor receptors, and induction of angiogenesis. Moreover, PGE2 is an important player in the tumor microenvironment, where it suppresses antitumor immunity and regulates tumor immune evasion, leading to increased tumoral progression. In this review, we describe the current knowledge on the pro-tumoral activity of PGE2 focusing on its role in cancer progression and in the regulation of the tumor microenvironment.

Molecular docking analysis of COX-2 for potential inhibitors

Cyclooxygenase-2 (COX-2) is liked with breast cancer. Therefore, it is of interest to design and develop new yet effective compounds against COX-2 from medicinal plants such as the natural alkaloid compounds. We document the optimal binding features of aristolochicacid with COX-2 protein for further consideration.

Neoadjuvant Endocrine Therapy in Breast Cancer: Current Knowledge and Future Perspectives

In locally advanced (LA) breast cancer (BC), neoadjuvant treatments have led to major achievements, which hold particular relevance in HER2-positive and triple-negative BC. Conversely, their role in hormone receptor positive (HR+), hormone epidermal growth factor 2 negative (HER2-) BC is still under debate, mainly due to the generally low rates of pathological complete response (pCR) and lower accuracy of pCR as predictors of long-term outcomes in this patient subset. While administration of neoadjuvant chemotherapy (NCT) in LA, HR+, HER2- BC patients is widely used in clinical practice, neoadjuvant endocrine therapy (NET) still retains an unfulfilled potential in the management of these subgroups, particularly in elderly and unfit patients. In addition, NET has gained a central role as a platform to test new drugs and predictive biomarkers in previously untreated patients. We herein present historical data regarding Tamoxifen and/or Aromatase Inhibitors and a debate on recent evidence regarding agents such as CDK4/6 and PI3K/mTOR inhibitors in the neoadjuvant setting. We also discuss key issues concerning the optimal treatment length, appropriate comparisons with NCT efficacy and use of NET in premenopausal patients.

Antiproliferative and antimigratory effects of 3-(4-substituted benzyl)-5- isopropyl-5-phenylhydantoin derivatives in human breast cancer cells

In this study, a series of synthesized 3-(4-substituted benzyl)-5-isopropyl-5-phenylhydantoin derivatives as a potential antiproliferative and antimigratory agents were investigated. The possible antitumor mechanisms of investigated hydantoin derivatives were examined on human breast cancer cell line MDA-MB-231. The cells were treated with different concentrations of compounds (from 0.01 µM to 100 µM) during 24 h and 72 h. The proliferation index, nitric oxide production, apoptosis rate, and migration capacity were measured. The cell invasion potential was examined by measuring the level of MMP-9 and COX-2 gene expression. All tested compounds expressed antiproliferative activity and induced dose- and time-dependent increase in the level of nitrites. The investigated molecules significantly decreased cell survival rate, migration capacity and the expression levels of genes included in the process of tumor invasion. Obtained data suggest that the tested hydantoin derivatives express considerable antitumor activity by reducing cell division rate, elevating apoptosis level, and inhibiting the motility and invasiveness of breast cancer cells. The results obtained in this study indicate that investigated compounds express potential as a novel chemotherapeutic agents against breast cancer growth and progression.

NSAID therapy for PIK3CA-Altered colorectal, breast, and head and neck cancer

Epidemiologic evidence indicates that regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) provides a protective effect against the development of colorectal, breast, and head and neck cancers. Genomic characterization of these cancers has lent considerable insight into the subpopulations of cancer patients who are most likely to benefit from NSAID therapy. The PIK3CA gene encodes the catalytic subunit of phosphatidylinositol 3-kinase (PI3K) and is among the most frequently mutated genes in solid tumor malignancies. Cancer-associated mutations in PIK3CA promote signaling via the PI3K pathway and stimulate tumor cell growth. In addition, activation of the PI3K pathway leads to induction of cyclooxygenase-2 (COX-2) enzyme and production of immunosuppressive prostaglandin E2 (PGE2). Notably, in both colorectal cancer and head and neck cancer the subpopulation of patients that benefit from NSAID use is restricted to those whose tumors exhibit PIK3CA genomic alterations. Preclinical studies, particularly in models of head and neck cancer, support the hypothesis that the chemopreventive impact of NSAIDs may be due, in part, to inhibition of COX-2 and reduction of PGE2 levels in the tumor microenvironment.

Efficacy and acceptability of neoadjuvant endocrine therapy in patients with hormone receptor-positive breast cancer: A network meta-analysis

BACKGROUND

The optimal sequence of endocrine therapy in a neoadjuvant setting for hormone receptor-positive (HR+) breast cancer is unclear. Our study evaluated the efficacy and acceptability of neoadjuvant endocrine therapy for HR+ breast cancer.

METHODS

We identified studies based on titles and abstracts that were published before 22 June 2018 in the following databases: PubMed, EMBASE, and the Cochrane Library. Eligible studies were randomised controlled trials with at least one arm that evaluated the effectiveness of one or a combination of anastrozole, letrozole, palbociclib, tamoxifen, fulvestrant, abemaciclib, everolimus, gefitinib, ribociclib, taselisib, and exemestane. We pooled effect sizes using the odds ratio (OR) and corresponding 95% credibility interval (95% CrI). The primary outcomes were response rate and treatment completion.

RESULTS

Our network meta-analysis included 3,306 participants and 16 eligible studies, which assessed 15 treatments. In terms of response rates, compared with letrozole combined therapy, tamoxifen was associated with a significant reduction in response rate (OR, 0.34; 95% CrI, 0.13-0.85; OR, 0.32; 95% CrI, 0.13-0.80; OR, 0.26; 95% CrI, 0.09-0.83; and OR, 0.30; 95% CrI, 0.09-0.96; for letrozole plus everolimus, letrozole plus taselisib, letrozole plus zoledronic acid, and letrozole plus lapatinib, respectively). Based on the surface under the cumulative ranking curves ranking, letrozole plus zoledronic acid was associated with the highest rate of response (87.6%), followed by letrozole plus lapatinib (85.2%), and letrozole plus taselisib (79.3%).

CONCLUSIONS

Ultimately, our study established that letrozole plus zoledronic acid may be an optimal treatment based on its current rank in a neoadjuvant setting for HR+ breast cancer.

The prognostic roles of cyclooxygenase-2 for patients with basal cell carcinoma

Background: Cyclooxygenase-2 (Cox-2) is critical for tumor invasion, angiogenesis, and poor prognosis in many human cancers. It was reported to be an abnormal expression in many human malignancies, including basal cell carcinoma (BCC). However, the prognostic significance of cox-2 in BCC was still unclear. The aim of this study was to investigate the prognostic roles of cox-2 for patients with BCC. Methods: We detected the expression of cox-2 both at mRNA and protein level in tumor tissue and adjacent normal tissues from 180 patients with BCC by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis, respectively. Results: Cox-2 expression was significantly increased in BCC tissues compared with the adjacent normal cohorts (p < .001). Its expression was significantly associated with angiogenesis (p < .001) and depth of invasion (p < .001). Kaplan-Meier analysis suggested patients with high expression of cox-2 had a shorter overall survival rate than those with low expression (log rank test, p < .001). Conclusions: The expression of cox-2 was up-regulated in BCC and it could be used as a bio-marker for the prognosis of BCC patients with a high risk of recurrence.

Celecoxib in breast cancer prevention and therapy

Breast cancer has a high incidence worldwide. The results of substantial studis reveal that inflammation plays an important role in the initiation, development, and aggressiveness of many malignancies. The use of celecoxib, a novel NSAID, is repetitively associated with the reduced risk of the occurrence and progression of a number of types of cancer, particularly breast cancer. This observation is also substantiated by various meta-analyses. Clinical trials have been implemented on integration treatment of celecoxib and shown encouraging results. Celecoxib could be treated as a potential candidate for antitumor agent. There are, nonetheless, some unaddressed questions concerning the precise mechanism underlying the anticancer effect of celecoxib as well as its activity against different types of cancer. In this review, we discuss different mechanisms of anticancer effect of celecoxib as well as preclinical/clinical results signifying this beneficial effect.

The down-regulation of microRNA-137 contributes to the up-regulation of retinoblastoma cell proliferation and invasion by regulating COX-2/PGE2 signaling

MicroRNA-137 (miR-137) plays an important role in the development and progression of many types of human cancers; however, the role of miR-137 in retinoblastoma (RB) remains unclear. In this study, we aimed to investigate the functional significance and molecular mechanisms of miR-137 in RB. We reported that miR-137 was frequently down-regulated in RB tissues and cell lines. The overexpression of miR-137 inhibited RB cell proliferation and invasion, while the suppression of miR-137 promoted RB cell proliferation and invasion. Bioinformatic analysis predicted that cyclooxygenase-2 (COX-2) was a potential target gene of miR-137, which was validated by a dual-luciferase reporter assay. Moreover, our results showed that miR-137 negatively regulated the expression of COX-2 and the production of prostaglandin E2 (PGE2) in RB cells. The knockdown of COX-2 suppressed the proliferation and invasion of RB cells as well as the production of PGE2. The overexpression of COX-2 significantly reversed the inhibitory effect of miR-137 overexpression on RB cell proliferation and invasion. Taken together, these results suggest that miR-137 suppresses the proliferation and invasion of RB cells by targeting COX-2/PGE2. Our study reveals a tumor suppressive role of miR-137 in the progression of RB and suggests miR-137 as a potentially effective therapeutic target for the treatment of RB.

Obesity and breast cancer - Role of estrogens and the molecular underpinnings of aromatase regulation in breast adipose tissue

One in eight women will develop breast cancer over their lifetime making it the most common female cancer. The cause of breast cancer is multifactorial and includes hormonal, genetic and environmental cues. Obesity is now an accepted risk factor for breast cancer in postmenopausal women, particularly for the hormone-dependent subtype of breast cancer. Obesity, which is characterized by an excess accumulation of body fat, is at the origin of chronic inflammation of white adipose tissue and is associated with dramatic changes in the biology of adipocytes leading to their dysfunction. Inflammatory factors found in the breast of obese women considerably impact estrogen signaling, mainly by driving changes in aromatase expression the enzyme responsible for estrogen production, and therefore promote tumor formation and progression. There is thus a strong link between adipose inflammation and estrogen biosynthesis and their signaling pathways converge in obese patients. This review describes how obesity-related factors can affect the risk of hormone-dependent breast cancer, highlighting the different molecular mechanisms and metabolic pathways involved in aromatase regulation, estrogen production and breast malignancy in the context of obesity.

Role of Aspirin in Breast Cancer Survival

Chemotherapy and hormonal therapy have significantly decreased breast cancer mortality, although with considerable side effects and financial costs. In the USA, over three million women are living after a breast cancer diagnosis and are eager for new treatments that are low in toxicity and cost. Multiple observational studies have reported improved breast cancer survival with regular aspirin use. Furthermore, pooled data from five large randomized trials of aspirin for cardiovascular disease showed that subjects on aspirin had decreased risk of cancer mortality and decreased risk of metastatic cancer. Although the potential mechanism for aspirin preventing breast cancer is not known, possible pathways may involve platelets, inflammation, cyclooxygenase (COX) 2, hormones, or PI3 kinase. This review article summarizes the current epidemiologic and clinical trial evidence as well as possible underlying mechanisms that justify current phase III randomized trials of aspirin to improve breast cancer survival.

Neoadjuvant palbociclib on ER+ breast cancer (N007): clinical response and EndoPredict's value

The purpose of the study was to test the efficacy of neoadjuvant palbociclib therapy and to evaluate its impact on cell cycle arrest and changes in EndoPredict (EP) scores before and after treatment. Postmenopausal women with histologically proven ER+ve, HER2-ve invasive breast cancer, 2 cm or greater, were enrolled in an open-label, single-arm study. Twenty eligible patients were given letrozole 2.5 mg per day together with palbociclib 125 mg per day for 3 out of 4 weeks in repeated cycles for 16 weeks (4 cycles) before surgery. The primary end points were clinical response rates (cRR) and preoperative endocrine prognostic index (PEPI). The secondary end points were pathologic response and gene expression testing with EP test on collected tumor samples. The following results were obtained. 17 patients showed a clinical response of 50% or more, including 8 complete responses and 9 partial responses. There was significant reduction in area (P < 0.0001) and volume (P = 0.017) of the cancer. Pathologic complete response (pCR) was achieved in one patient; all cancers were downgraded after treatment. Ki67 (P = 0.044) and EP scores (P < 0.0001) were significantly reduced after treatment. Analysis of the relative gene expression levels showed that all proliferative genes, IL6ST and RBBP8 were decreased after palbociclib treatment. 6 patients with intermediate and three patients with high PEPI risk scores were found to have low EPclin scores. All patients with high PEPI relapse risk score had high EPclin score. In conclusion, effective clinical response was demonstrated by neoadjuvant letrozole in combination with palbociclib. Compared with PEPI, EPclin might be a better parameter to estimate prognosis after neoadjuvant therapy.

Changes of tumor infiltrating lymphocyte subtypes before and after neoadjuvant endocrine therapy in estrogen receptor-positive breast cancer patients – an immunohistochemical study of cd8+ and foxp3+ using double immunostaining with correlation to the pathobiological response of the patients

Tumor-stromal interactions involve continuous crosstalk and interactions among different cell types and play pivotal roles in tumorigenesis, tumor development, disease progression, subsequent metastasis, and also tumor response to therapeutic agents. Tumor infiltrating lymphocytes (TILs) are important components of these tumor-stromal interactions. Specific TIL subtypes are known to be involved in the clinical course of individual patients. However, the status of TILs following endocrine therapy has not been studied in breast cancer patients. We evaluated the alterations of TIL subtypes in a cohort of East Asian patients with estrogen receptor-positive breast cancer during the course of neoadjuvant steroidal aromatase inhibitor (AI) therapy, using double immunohistochemical staining of CD8+ and T regulatory cells (Treg) or Foxp3+, yielding the CD8+/Treg ratio in individual patients. Changes in CD8+/Treg ratio before and after therapy were then correlated with pathobiological responses of individual patients based upon alterations of the Ki-67 labeling index (LI). A significant increase in the CD8+/Treg ratio was detected in responders (p=0.028) but not in non-responders, which may reflect the dynamic process in which the host immune response to tumor antigens changed in consequence of an interaction between tumor and stromal cells in its microenvironment following estrogen depletion caused by the AI. The CD8+/Treg ratio in breast cancer tissue can be a potential surrogate marker in surgical pathology specimens for predicting responses to neoadjuvant endocrine therapy, not only incorporating features of carcinoma cells as in Ki-67 LI but also those of adjacent stromal cells in the tumor microenvironment, especially in the early stage of treatment prior to any detectable clinical and/or histopathological changes.

Neoadjuvant Endocrine Therapy: Who Benefits Most?

Neoadjuvant endocrine therapy (NET) can be effective at downstaging patients with estrogen receptor-positive tumors and identifying those tumors that are endocrine sensitive and resistant. The optimal prognostic markers for stratification are under investigation. Use of NET will allow the identification of patients with estrogen receptor-positive tumors who might benefit from additional treatment and allow better understanding of endocrine resistance.

Neoadjuvant Endocrine Therapy for Estrogen Receptor-Positive Breast Cancer: A Systematic Review and Meta-analysis

Importance

Estrogen receptor-positive (ER+) tumors of the breast are generally highly responsive to endocrine treatment. Although endocrine therapy is the mainstay of adjuvant treatment for ER+ breast cancer, the role of endocrine therapy in the neoadjuvant setting is unclear.

Objective

To evaluate the effect of neoadjuvant endocrine therapy (NET) on the response rate and the rate of breast conservation surgery (BCS) for ER+ breast cancer.

Data Sources

Based on PRISMA guidelines, a librarian-led search of PubMed and Ovid MEDLINE was performed to identify eligible trials published from inception to May 15, 2015. The search was performed in May 2015.

Study Selection

Inclusion criteria were prospective, randomized, neoadjuvant clinical trials that reported response rates with at least 1 arm incorporating NET (n = 20). Two authors independently analyzed the studies for inclusion.

Data Extraction and Synthesis

Pooled odds ratios (ORs), 95% CIs, and P values were estimated for end points using the fixed- and random-effects statistical model.

Results

The analysis included 20 studies with 3490 unique patients. Compared with combination chemotherapy, NET as monotherapy with aromatase inhibitors had a similar clinical response rate (OR, 1.08; 95% CI, 0.50-2.35; P = .85; n = 378), radiological response rate (OR, 1.38; 95% CI, 0.92-2.07; P = .12; n = 378), and BCS rate (OR, 0.65; 95% CI, 0.41-1.03; P = .07; n = 334) but with lower toxicity. Aromatase inhibitors were associated with a significantly higher clinical response rate (OR, 1.69; 95% CI, 1.36-2.10; P < .001; n = 1352), radiological response rate (OR, 1.49; 95% CI, 1.18-1.89; P < .001; n = 1418), and BCS rate (OR, 1.62; 95% CI, 1.24-2.12; P < .001; n = 918) compared with tamoxifen. Dual combination therapy with growth factor pathway inhibitors was associated with a higher radiological response rate (OR, 1.59; 95% CI, 1.04-2.43; P = .03; n = 355), but not clinical response rate (OR, 0.76; 95% CI, 0.54-1.07; P = .11; n = 537), compared with endocrine monotherapy. The incidence of pathologic complete response was low (<10%).

Conclusions and Relevance

Neoadjuvant endocrine therapy, even as monotherapy, is associated with similar response rates as neoadjuvant combination chemotherapy but with significantly lower toxicity, suggesting that NET needs to be reconsidered as a potential option in the appropriate setting. Additional research is needed to develop rational NET combinations and predictive biomarkers to personalize the optimal neoadjuvant strategy for ER+ breast cancer.

Implementing neoadjuvant endocrine strategies in ER-positive, HER2-negative breast cancer

INTRODUCTION

Although neoadjuvant chemotherapy has been widely adopted as it increases breast conservation rates, permits the in vivo testing of the activity of chemotherapeutics and offers the opportunity to conduct translational research based on longitudinal assessments of tumor tissue, neoadjuvant endocrine therapy has been met with skepticism owing to slow regression rates and a low chance for pathologic remission. Areas covered: Herein, the results of clinical trials comparing different endocrine agents as neoadjuvant treatment, endocrine therapy with chemotherapy, treatment duration, novel combinations and putative biomarkers are reviewed, with the aim to better understand the current and future role of this modality in clinical practice. Expert commentary: Available evidence clearly indicates that, in properly selected patients, short-term outcomes do not differ compared to chemotherapy. In addition, the realization that its effects at the cellular level occur shortly after its initiation and have important prognostic implications, could serve as a tool for the early identification of non-responders. Ongoing trials which integrate novel agents in addition to endocrine therapies will help guide treatment decisions and may establish neoadjuvant endocrine therapy as a standard of care for well-defined patient subgroups.

Cyclooxygenase-2 regulates TGFβ-induced cancer stemness in triple-negative breast cancer

Triple negative breast cancer (TNBC), an aggressive subtype of breast cancer, display poor prognosis and exhibit resistance to conventional therapies, partly due to an enrichment in breast cancer stem cells (BCSCs). Here, we investigated the role of the cyclooxygenase-2 (COX-2), a downstream target of TGFβ, in regulating BCSCs in TNBC. Bioinformatics analysis revealed that COX-2 is highly expressed in TNBC and that its expression correlated with poor survival outcome in basal subtype of breast cancer. We also found TGFβ-mediated COX-2 expression to be Smad3-dependent and to be required for BCSC self-renewal and expansion in TNBCs. Knocking down COX-2 expression strikingly blocked TGFβ-induced tumorsphere formation and TGFβ-induced enrichment of the two stem-like cell populations, CD24^lowCD44^high and ALDH+ BCSCs. Blocking COX-2 activity, using a pharmacological inhibitor also prevented TGFβ-induced BCSC self-renewal. Moreover, we found COX-2 to be required for TGFβ-induced expression of mesenchymal and basal breast cancer markers. In particular, we found that TGFβ-induced expression of fibronectin plays a central role in TGFβ-mediated breast cancer stemness. Together, our results describe a novel role for COX-2 in mediating the TGFβ effects on BCSC properties and imply that targeting the COX-2 pathway may prove useful for the treatment of TNBC by eliminating BCSCs.

Uptake of exemestane chemoprevention in postmenopausal women at increased risk for breast cancer

Despite their efficacy, uptake of selective estrogen receptor modulators for breast cancer chemoprevention remains low. Exemestane, an aromatase inhibitor, has recently been identified as a potential chemopreventive option with fewer serious side effects compared with selective estrogen receptor modulators in postmenopausal women. The purpose of this study was to assess the uptake of exemestane in a breast cancer prevention clinic. A retrospective chart review was conducted to capture chemoprevention uptake by postmenopausal women presenting to the Yale Breast Cancer Prevention Clinic between November 2011 and November 2012. Descriptive statistics of the study population have been presented. Statistical analyses were carried out using SAS 9.3 (SAS Institute Inc., Cary, North Carolina, USA) between December 2012 and February 2013. Of 90 postmenopausal women, 56 were eligible for chemoprevention. Their mean age was 56.8 years. Among the women, 39% had osteopenia or osteoporosis. Thirteen women chose to start chemoprevention medication (23%). Although 31% of the chemopreventive medication administered included exemestane, only four of 56 postmenopausal women opted for exemestane (7%). Chemoprevention uptake rates of postmenopausal women in the setting of a breast cancer prevention clinic are higher than that reported in the general population; however, they remain low overall despite the inclusion of exemestane as an option. A significant proportion of postmenopausal women have decreased bone density, which is a potential barrier to exemestane uptake. The results provide practical implications suggesting that exemestane may have limited impact on breast cancer chemoprevention uptake. Further investigations should focus on understanding the factors that influence, predict, and increase chemoprevention uptake.

Network Meta-Analysis of the Effectiveness of Neoadjuvant Endocrine Therapy for Postmenopausal, HR-Positive Breast Cancer

In clinical practice, it is necessary to define an optimal choice from many different therapeutic regimens. This study aimed to assess the efficacy and safety of neoadjuvant endocrine therapy (NET) for breast cancer patients. Randomized clinical trials were included. Nine studies comprising 2133 patients were included in the final analysis. Network meta-analysis showed that everolimus plus letrozole was more easily accepted by patients than exemestane (≥20wks) (odds ratio (OR): 856697.02, 95% confidence intervals (95%CI): 1.88 to 87242934...); exemestane (≥20wks) had worse acceptability than letrozole (OR: 0.00, 95%CI: 0.00 to 0.98). Letrozole produced a better clinical objective response (COR) than tamoxifen (OR: 1.99, 95%CI: 1.04 to 3.80). The incidence of fatigue between the anastrozole plus gefitinib group and the everolimus plus letrozole group was significantly different (OR: 0.08, 95%CI: 0.01 to 0.83). The exemestane (<20wks) plus celecoxib group had fewer hot flushes than others. Ranking showed the everolimus plus letrozole was most likely rank first in comparisons of COR and acceptability, and had a 64% possibility to rank first after stochastic multi-criteria acceptability analysis. In conclusion, our study showed that letrozole plus everolimus is the most effective treatment for postmenopausal, hormone receptor-positive breast cancer in the neoadjuvant setting.

COX-2 modulates mammary tumor progression in response to collagen density

Background

High breast density is linked to an increased risk of breast cancer, and correlates with changes in collagen. In a mouse model of mammary carcinoma in the context of increased collagen deposition, the MMTV-PyMT/Col1a1^tm1jae, there is accelerated mammary tumor formation and progression. Previous gene expression analysis suggests that increased collagen density elevates expression of PTGS2 (prostaglandin-endoperoxide synthase 2), the gene for cyclooxygenase-2 (COX-2).

Methods

To understand the role of COX-2 in tumor progression within a collagen-dense microenvironment, we treated MMTV-PyMT or MMTV-PyMT/Col1a1^tm1jae tumors prior to and after tumor formation. Animals received treatment with celecoxib, a specific COX-2 inhibitor, or placebo. Mammary tumors were examined for COX-2, inflammatory and stromal cell components, and collagen deposition through immunohistochemical analysis, immunofluorescence, multiplex cytokine ELISA and tissue imaging techniques.

Results

PyMT/Col1a1^tm1jae tumors were larger, more proliferative, and expressed higher levels of COX-2 and PGE2 than PyMT tumors in wild type (WT) mice. Treatment with celecoxib significantly decreased the induced tumor size and metastasis of the PyMT/Col1a1 tumors, such that their size was not different from the smaller PyMT tumors. Celecoxib had minimal effect on the PyMT tumors. Celecoxib decreased expression levels of COX-2, PGE2, and Ki-67. Several cytokines were over-expressed in PyMT/Col1a1 compared to PyMT, and celecoxib treatment prevented their over-expression. Furthermore, macrophage and neutrophil recruitment were enhanced in PyMT/Col1a1 tumors, and this effect was inhibited by celecoxib. Notably, COX-2 inhibition reduced overall collagen deposition. Finally, when celecoxib was used prior to tumor formation, PyMT/Col1a1 tumors were fewer and smaller than in untreated animals.

Conclusion

These findings suggest that COX-2 has a direct role in modulating tumor progression in tumors arising within collagen-dense microenvironments, and suggest that COX-2 may be an effective therapeutic target for women with dense breast tissue and early-stage breast cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0695-3) contains supplementary material, which is available to authorized users.

The use of cyclooxygenase-2 inhibitors for improvement of efficacy of radiotherapy in cancers

Cyclooxygenase-2 (COX-2) is overexpressed in cancer cells and is associated with carcinogenesis and maintenance of progressive tumour growth as well as resistance of cancer cells to ionising radiation (IR). COX-2 inhibitors can attenuate tumour growth and expression of markers of cell proliferation as well as induce apoptosis in tumour cells. These agents can have a synergistic effect with IR in the killing of cancer cells. In this review, we discuss the rational basis and molecular mechanisms regarding the usefulness of COX-2 inhibitors in cancer therapy, and also their potential role in increasing the therapeutic index of chemoradiation by protecting normal cells and sensitising tumour cells to radiotherapy.

Interaction of Salicylates and the Other Nonsteroidal Anti-Inflammatory Agents With Breast Cancer Endocrine Treatment: Systematic Review

Despite advances in breast cancer treatment, mortality from breast cancer is still high. Undoubtedly, novel treatment strategies are needed for chemoprevention of high-risk women and for the treatment of receptor-negative breast cancer. An appealing strategy would be the combination of breast endocrine treatment with salicylates and the other nonsteroidal anti-inflammatory agents (NSAIDs). This systematic review aimed to synthesize evidence on the possible synergistic antitumor effect of breast cancer endocrine treatment with salicylates and the other NSAIDs. Electronic databases were searched with the appropriate search terms. Most of the identified studies investigated the possible synergistic effect of exemestane with celecoxib in different clinical settings including metastatic treatment, adjuvant treatment, ductal carcinoma in situ. The possible synergistic effect of tamoxifen with celecoxib was investigated in one experimental study and the possible synergistic effect of exemestane with aspirin was investigated in another experimental study. Synergistic effect was detected in the majority of the studies. In conclusion, existing limited evidence suggests synergistic interaction of salicylates and the other NSAIDs in the treatment of estrogen responsive breast cancer with clinical implications in the reversal of acquired resistance to breast cancer endocrine treatment and in chemoprophylaxis.

Neoadjuvant endocrine treatment in early breast cancer: An overlooked alternative?

During the last decade neoadjuvant endocrine therapy (NET) has moved from being reserved for elderly and frail non-chemotherapy candidates to a primary systemic modality in selected patients with hormone sensitive breast cancer. Neoadjuvant hormonal treatment in patients with hormone receptor positive, HER-2 negative early breast cancer is proven to be an effective and safe option; it is associated with a higher rate of breast conserving surgery (BCS), may reduce the need for adjuvant chemotherapy and enables a delay of surgery for medical or practical reasons. Clinical responses range from 13% to 100% with at least 3 months of NET. Methods of assessing response should include MRI of the breast, particularly in lobular tumours. In studies comparing tamoxifen with aromatase inhibitors (AI), AI proved to be superior in terms of tumour response and rates of BCS. Change in Ki67 is accepted as a validated endpoint for comparing endocrine neoadjuvant agents. Levels of Ki67 during treatment are more closely related to long-term prognosis than pretreatment Ki67. Neoadjuvant endocrine therapy provides a unique opportunity for studies of endocrine responsiveness and the development of new experimental drugs combined with systemic hormonal treatment.

Effect of targeted agents on the endocrine response of breast cancer in the neoadjuvant setting: a systematic review

Inhibition of aberrantly activated pathways cross-talking with hormone receptor (HR) improves response to endocrine therapy in patients with HR-positive advanced breast cancer. We performed a Pubmed database systematic review to ascertain the existence of a better clinical response when combining endocrine therapy with targeted agents in the neoadjuvant setting. Preclinical studies or trials evaluating toxicity were excluded.

We found nine phase II trials that fulfilled the research criteria. The endocrine agents used were third generation aromatase inhibitors (AIs), anastrozole, letrozole or exemestane. The investigated targeted agents were inhibitors of tyrosine kinase receptors such as gefitinib, imatinib or trastuzumab/lapatinib, inhibitors of mTOR, such as everolimus, inhibitors of COX-2, such as celecoxib, and inhibitors of angiogenesis, such as bevacizumab. The response rate (RR) observed combining endocrine and targeted agents ranged between 36% and 90%.

Overall the studies failed to show a remarkable advantage in RR in the combination group compared to historical control subjects receiving AIs alone.

Targeting the COX-2 Pathway to Improve Therapeutic Response in the Obese Breast Cancer Patient Population

Multiple studies have demonstrated that obesity is associated with a worse outcome for all breast cancer subtypes and that obese breast cancer patients do not respond as well as normal weight patients to aromatase inhibitor treatment and chemotherapy. While a number of mechanisms have been proposed to explain this link, recent studies have provided evidence that elevated local cyclooxygenase-2 (COX-2) expression and the resulting increase in prostaglandin E2 (PGE2) production may play an important role. COX-2 upregulation in breast tumors is associated with a poor prognosis, a connection generally attributed to PGE2's direct effects on apoptosis and invasion as well as its stimulation of pre-adipocyte aromatase expression and subsequent estrogen production. Research in this area has provided a strong foundation for the hypothesis that COX-2 signaling is involved in the obesity-breast cancer link, and further study regarding the role of COX-2 in this link is warranted.

A Canadian national expert consensus on neoadjuvant therapy for breast cancer: linking practice to evidence and beyond

BACKGROUND

Use of the neoadjuvant approach to treat breast cancer patients has increased since the early 2000s, but the overall pathway of care for such patients can be highly variable. The aim of our project was to establish a multidisciplinary consensus among clinicians with expertise in neoadjuvant therapy (nat) for breast cancer and to determine if that consensus reflects published methods used in randomized controlled trials (rcts) in this area.

METHODS

A modified Delphi protocol, which used iterative surveys administered to 85 experts across Canada, was established to obtain expert consensus concerning all aspects of the care pathway for patients undergoing nat for breast cancer. All rcts published between January 1, 1967, and December 1, 2012, were systematically reviewed. Data extracted from the rcts were analyzed to determine if the methods used matched the expert consensus for specific areas of nat management. A scoring system determined the strength of the agreement between the literature and the expert consensus.

RESULTS

Consensus was achieved for all areas of the pathway of care for patients undergoing nat for breast cancer, with the exception of the role of magnetic resonance imaging in the pre-treatment or preoperative setting. The levels of agreement between the consensus statements and the published rcts varied, primarily because specific aspects of the pathway of care were not well described in the reviewed literature.

CONCLUSIONS

A true consensus of expert opinion concerning the pathway of care appropriate for patients receiving nat for breast cancer has been achieved. A review of the literature illuminated gaps in the evidence about some elements of nat management. Where evidence is available, agreement with expert opinion is strong overall. Our study is unique in its approach to establishing consensus among medical experts in this field and has established a pathway of care that can be applied in practice for patients receiving nat.

NSAID use reduces breast cancer recurrence in overweight and obese women: role of prostaglandin-aromatase interactions

Obesity is associated with a worse breast cancer prognosis and elevated levels of inflammation, including greater cyclooxygenase-2 (COX-2) expression and activity in adipose-infiltrating macrophages. The product of this enzyme, the proinflammatory eicosanoid prostaglandin E2 (PGE2), stimulates adipose tissue aromatase expression and subsequent estrogen production, which could promote breast cancer progression. This study demonstrates that daily use of a nonsteroidal anti-inflammatory drug (NSAID), which inhibits COX-2 activity, is associated with reduced estrogen receptor α (ERα)-positive breast cancer recurrence in obese and overweight women. Retrospective review of data from ERα-positive patients with an average body mass index of >30 revealed that NSAID users had a 52% lower recurrence rate and a 28-month delay in time to recurrence. To examine the mechanisms that may be mediating this effect, we conducted in vitro studies that utilized sera from obese and normal-weight patients with breast cancer. Exposure to sera from obese patients stimulated greater macrophage COX-2 expression and PGE2 production. This was correlated with enhanced preadipocyte aromatase expression following incubation in conditioned media (CM) collected from the obese-patient, sera-exposed macrophages, an effect neutralized by COX-2 inhibition with celecoxib. In addition, CM from macrophage/preadipocyte cocultures exposed to sera from obese patients stimulated greater breast cancer cell ERα activity, proliferation, and migration compared with sera from normal-weight patients, and these differences were eliminated or reduced by the addition of an aromatase inhibitor during CM generation. Prospective studies designed to examine the clinical benefit of NSAID use in obese patients with breast cancer are warranted.

The role of the PGE2-aromatase pathway in obesity-associated breast inflammation

Subbaramaiah and colleagues present the first evidence indicating that a cyclooxygenase-2-prostaglandin E(2)-aromatase pathway promotes obesity-associated inflammation in women's breast tissues. Their findings shed new light on obesity-associated inflammation in general and provide a rationale for developing effective chemopreventive and therapeutic strategies targeting this pathway for obese women with breast inflammation and patients with hormone-dependent breast cancer.

Non-steroidal anti-inflammatory drug use, hormone receptor status, and breast cancer-specific mortality in the Carolina Breast Cancer Study

Epidemiologic studies report a protective association between non-steroidal anti-inflammatory drug (NSAID) use and hormone receptor-positive breast cancer risk, a finding consistent with NSAID-mediated suppression of aromatase-driven estrogen biosynthesis. However, the association between NSAID use and breast cancer-specific mortality is uncertain and it is unknown whether this relationship differs by hormone receptor status. This study comprised 935 invasive breast cancer cases, of which 490 were estrogen receptor (ER)-positive, enrolled between 1996 and 2001 in the Carolina Breast Cancer Study. Self-reported NSAID use in the decade prior to diagnosis was categorized by duration and regularity of use. Differences in tumor size, stage, node, and receptor status by NSAID use were examined using Chi-square tests. Associations between NSAID use and breast cancer-specific mortality were examined using age- and race-adjusted Cox proportional hazards analysis. Tumor characteristics did not differ by NSAID use. Increased duration and regularity of NSAID use was associated with reduced breast cancer-specific mortality in women with ER-positive tumors (long-term regular use (≥8 days/month for ≥ 3 years) versus no use; hazard ratio (HR) 0.48; 95 % confidence interval (CI) 0.23-0.98), with a statistically significant trend with increasing duration and regularity (p-trend = 0.036). There was no association for ER-negative cases (HR 1.19; 95 %CI 0.50-2.81; p-trend = 0.891). Long-term, regular NSAID use in the decade prior to breast cancer diagnosis was associated with reduced breast cancer-specific mortality in ER-positive cases. If confirmed, these findings support the hypothesis that potential chemopreventive properties of NSAIDs are mediated, at least in part, through suppression of estrogen biosynthesis.

Invasive lobular breast cancer and its variants: how special are they for systemic therapy decisions?

The WHO classification of breast tumors distinguishes, besides invasive breast cancer 'of no special type' (former invasive ductal carcinoma, representing 60-70% of all breast cancers), 30 special types, of which invasive lobular carcinoma (ILC) is the most common (5-15%). We review the literature on (i) the specificity and heterogeneity of ILC biology as documented by various analytical techniques, including the results of molecular testing for risk of recurrence; (ii) the impact of lobular histology on prediction of prognosis and effect of systemic therapies in patients. Though it is generally admitted that ILC has a better prognosis than IDC, is endocrine responsive, and responds poorly to chemotherapy, currently available data do not unanimously support these assumptions. This review demonstrates some lack of specific data and a need for improving clinical research design to allow oncologists to make informed systemic therapy decisions in patients with ILC. Importantly, future studies should compare various endpoints in ILC breast cancer patients among the group of hormonosensitive breast cancer.

COX-2 expression is predictive for early relapse and aromatase inhibitor resistance in patients with ductal carcinoma in situ of the breast, and is a target for treatment

BACKGROUND

Stratification of patients for treatment of ductal carcinoma in situ (DCIS) is suboptimal, with high systemic overtreatment rates.

METHODS

A training set of 95 tumours from women with pure DCIS were immunostained for proteins involved in cell survival, hypoxia, growth factor and hormone signalling. A generalised linear regression with regularisation and variable selection was applied to a multiple covariate Cox survival analysis with recurrence-free survival 10-fold cross-validation and leave-one-out iterative approach were used to build and test the model that was validated using an independent cohort of 58 patients with pure DCIS. The clinical role of a COX-2-targeting agent was then tested in a proof-of-concept neoadjuvant randomised trial in ER-positive DCIS treated with exemestane 25 mg day(-1)± celecoxib 800 mg day(-1).

RESULTS

The COX-2 expression was an independent prognostic factor for early relapse in the training (HR 37.47 (95% CI: 5.56-252.74) P=0.0001) and independent validation cohort (HR 3.9 (95% CI: 1.8-8.3) P=0.002). There was no significant interaction with other clinicopathological variables. A statistically significant reduction of Ki-67 expression after treatment with exemestane ± celecoxib was observed (P<0.02) with greater reduction in the combination arm (P<0.004). Concomitant reduction in COX-2 expression was statistically significant in the exemestane and celecoxib arm (P<0.03) only.

CONCLUSIONS

In patients with DCIS, COX-2 may predict recurrence, aiding clinical decision making. A combination of an aromatase inhibitor and celecoxib has significant biological effect and may be integrated into treatment of COX2-positive DCIS at high risk of recurrence.

Role of Cyclooxygenase 2 (COX-2) in Prognosis of Breast Cancer

COX-2 regulates tumour growth, invasion and metastasis in breast cancer. This study investigated the association between COX-2 expression in human breast cancer versus the expression of ER, PR, HER-2/neu, as well as its association with other established prognostic indicators like age, menopausal status, tumour size, lymph nodal status, stage, grade, NPI and histological subtype, and aims to validate the role of overexpression of COX-2 as a prognostic marker in patients with breast cancer in Indian subcontinent. In this hospital based study of 123 breast cancer patients (Group-A) and 76 female patients with benign breast disease (Group-B) attending a Comprehensive Breast Clinic at a reputed institute in Eastern India, COX-2 protein expression was measured from breast tissue using the Western Blot Technique. COX-2 mRNA expression was measured by RT-PCR Technique. ER, PR and HER-2/neu status was measured by immunohistochemistry methods. COX-2 was not expressed in the control group. The proportion of COX-2 positive tumours was significantly higher in patients of age >50 years [52(91.2 %), p < 0.01], postmenopausal status [64(90.1 %), p < 0.01], advanced stage of disease (p < 0.01), higher grade (p < 0.01), larger tumors (p < 0.01), metastatic lymph nodes (p < 0.01) and NPI ≥ 5.4 (p < 0.01). COX-2 expression was seen in ER-negative [66(95.7 %), p < 0.01], PR-negative [76(92.7 %), p < 0.01], and HER-2/neu positive tumours [29(100.0 %), p < 0.01]. Risk of COX-2 positivity was found to be 2.74 times more for postmenopausal status, 6.90 times more for large size tumours (≥ 2.5), 34.37 times more for node positive tumours, 9.26 times more with ER negative patients and 5.88 times more for PR negative patients. COX-2 expression is associated with established indicators of poor prognosis such as postmenopausal status, age >50 year, advanced stage of disease, large tumour size, higher grade, lymph node metastasis, NPI ≥ 5.4, ER negativity, PR negativity and HER-2/neu positivity. Thus, COX-2 expression implies aggressive tumour biology, and may play an important role as a prognostic marker.

LMTK3 is implicated in endocrine resistance via multiple signaling pathways

Resistance to endocrine therapy in breast cancer is common. With the aim of discovering new molecular targets for breast cancer therapy, we have recently identified LMTK3 as a regulator of the estrogen receptor-alpha (ERα) and wished to understand its role in endocrine resistance. We find that inhibition of LMTK3 in a xenograft tamoxifen (Tam)-resistant (BT474) breast cancer mouse model results in re-sensitization to Tam as demonstrated by a reduction in tumor volume. A whole genome microarray analysis, using a BT474 cell line, reveals genes significantly modulated (positively or negatively) after LMTK3 silencing, including some that are known to be implicated in Tam resistance, notably c-MYC, HSPB8 and SIAH2. We show that LMTK3 is able to increase the levels of HSPB8 at a transcriptional and translational level thereby protecting MCF7 cells from Tam-induced cell death, by reducing autophagy. Finally, high LMTK3 levels at baseline in tumors are predictive for endocrine resistance; therapy does not lead to alteration in levels, whereas in patient's plasma samples, acquired LMTK3 gene amplification (copy number variation) was associated with relapse while receiving Tam. In aggregate, these data support a role for LMTK3 in both innate (intrinsic) and acquired (adaptive) endocrine resistance in breast cancer.

Anastrozole and celecoxib for endometriosis treatment, good to keep them apart?

Endometriosis is a benign gynecological disease. Cyclooxygenase-2 (COX-2) and aromatase proteins have been shown to be overexpressed in eutopic endometrium from women suffering from this disease compared to disease-free women. Furthermore, inhibition of these molecules individually was demonstrated to have antiproliferative and proapoptotic effects both in vitro and in vivo in several models. In this study, the effect of combining celecoxib, a selective COX-2 inhibitor, and anastrozole, an aromatase inhibitor, on the implantation and growth of endometriotic like lesions in a murine model of endometriosis was evaluated. Endometriosis was surgically induced in female BALB/c mice. After 28 days of treatment with celecoxib, anastrozole, or their combination, animals were killed and lesions were counted, measured, excised, and fixed. Immunohistochemistry for proliferating cell nuclear antigen and CD34 was performed for assessment of cell proliferation and vascularization. TUNEL technique was performed for apoptosis evaluation. Celecoxib was the only treatment to significantly reduce the number of lesions established per mouse, their size and vascularized area. In addition, cell proliferation was significantly diminished and apoptosis was significantly enhanced by both individual treatments. When the therapies were combined, they reversed their effects. These results confirm that celecoxib and anastrozole separately decrease endometriotic growth, but when combined they might have antagonizing effects.

Long-term efficacy and safety of exemestane in the treatment of breast cancer

Exemestane, a steroidal aromatase inhibitor, is licensed for postmenopausal patients with estrogen receptor (ER)-positive breast cancer as second-line therapy in metastatic disease following antiestrogen failure and as part of sequential adjuvant therapy following initial tamoxifen. This study is a systematic literature review, evaluating exemestane in different clinical settings. The Ovid Medline (1948-2012), Embase (1980-2012), and Web of Science (1899-2012) databases were searched. Forty-two relevant articles covering randomized controlled trials were reviewed for efficacy and safety, and three for adherence. With regard to efficacy in metastatic disease, exemestane is superior to megestrol acetate after progression on tamoxifen. There is evidence for noninferiority to fulvestrant (following a prior aromatase inhibitor) and to nonsteroidal aromatase inhibitors in the first-line setting. Combined use with everolimus is shown to be more efficacious than exemestane alone following previous aromatase inhibitor use. In the adjuvant setting, a switch to exemestane after 2-3 years of tamoxifen is superior to 5 years of tamoxifen. Exemestane is noninferior to 5 years of tamoxifen as upfront therapy, and may have a role as an extended adjuvant therapy. Used as neoadjuvant therapy, increased breast conservation is achievable. As chemoprevention, exemestane significantly reduces the incidence of breast cancer in "at-risk" postmenopausal women. Exemestane is associated with myalgias and arthralgias, as well as reduced bone mineral density and increased risk of fracture, which do not appear to persist at follow-up, with subsequent return to pretreatment values. Compared with tamoxifen, there is a reduced incidence of endometrial changes, thromboembolic events, and hot flashes. Limited evidence shows nonadherence in 23%-32% of patients. Evidence is growing in support of exemestane in all clinical settings. It is generally more efficacious and has a better safety profile than tamoxifen. How it compares with the nonsteroidal aromatase inhibitors remains to be established. Further studies are required on adherence to ensure that maximum benefit is obtained.

The clinical trials of the Organisation for Oncology and Translational Research (OOTR)

The Organisation for Oncology and Translational Research (OOTR) was established in 2002 by Dr Louis WC Chow and Dr Masakazu Toi to gather medical professionals from different countries to work together in translational research as one of the missions of the organisation. Therefore, we seek to create networking among oncologists and develop effective interaction among the most advanced academic institutions throughout the world in order to conduct clinical trials and translational research together. Several clinical trials evaluating the use of neoadjuvant therapy for breast cancer have been designed and conducted for the past 10 years in the OOTR. The design of these studies has shifted from evaluating the efficacy and safety of new anticancer therapies and exploring new predictive and prognostic biomarkers to overcoming and unveiling the mechanism of tumor resistance as well as compiling predictive models for treatment response. This article briefly summarizes the concept and development of the OOTR clinical trial designs.

Early operable breast cancer in elderly women treated with an aromatase inhibitor letrozole as sole therapy

BACKGROUND

Primary endocrine therapy (PET) with aromatase inhibitors (AIs) is an option in elderly patients unfit for or unwilling to undergo surgery. We studied the outcome of patients treated with letrozole as PET.

METHODS

Patients with early oestrogen receptor (ER)/progesterone receptor (PR)-positive breast cancer treated with letrozole from February 2001 to September 2009 were reviewed. Inoperable and locally advanced tumours were excluded. Reasons for offering PET, response, survival, cause of death, time to initial and best response, fracture incidence, and late failure rates were studied.

RESULTS

In all, 104 patients received PET due to frailty (n=48), comorbidity (n=30), old age (n=9), and patient preference (n=17). Median follow-up was 56 months (4-106). Eighty-five cancers responded to letrozole (stable disease (SD, n=19), reduction in size (PR, n=42), and complete response ((CR), n=24)). Median survival was 51 months (4-103), time to initial response (PR/CR) 4.5 months (2-24), and time to best response 8.5 months (3-50). Letrozole was stopped in 25 patients due to progressive disease (n=19), side effects (n=5), and patient choice (n=1). Only 12 of 49 deaths were from breast cancer.

CONCLUSION

Letrozole is a reasonable alternative in elderly women with early ER/PR-positive invasive breast cancer who are unfit or unwilling to undergo standard therapy.

Phase II trial of neoadjuvant exemestane in combination with celecoxib in postmenopausal women who have breast cancer

PURPOSE

Within breast tissue, aromatase expression and activity is increased by prostaglandin E2, providing a rationale for combining the COX-2 inhibitor celecoxib with an aromatase inhibitor. To evaluate the effect of these drugs on aromatase and other biomarkers, a phase II trial of neoadjuvant exemestane followed sequentially by celecoxib plus exemestane was performed.

METHODS

Postmenopausal women with estrogen receptor (ER) and/or progesterone (PR) positive stages II-III breast cancers received 8 weeks of exemestane 25 mg daily, followed by 8 weeks of exemestane 25 mg daily and celecoxib 400 mg twice daily. Core biopsies were collected pretreatment, after 8 weeks of exemestane, and at definitive breast cancer surgery. A tissue microarray was constructed and immunohistochemistry (IHC) for aromatase, ER, PR, HER-2, Ki-67, and COX-2 was performed.

RESULTS

Twenty-two women were enrolled. Celecoxib was discontinued in 4 (18%) women for toxicity (all grade 1 and 2) and 2 (9%) developed serious cardiac events occurring at 1 and 4 months after completing treatment. By US, there were 8 (36%)-partial responses and 12 (55%)-stable disease. There were no pathological complete responses (pCR). There were statistically significant decreases in ER (P = .003), PR (P = .002), Ki-67 (P < .001), and COX-2 (P = .004) expression. No significant differences in aromatase or HER-2 expression were observed (P = .13 and P = .39, respectively).

CONCLUSION

The addition of celecoxib to exemestane was tolerated by the majority of women and anti-tumor response was observed. Additional studies, including gene expression, are required to more fully understand the basis for the decreased expression of ER, PR, Ki-67, and COX-2.

Bone metabolism and quality-of-life of postmenopausal women with invasive breast cancer receiving neoadjuvant hormonal therapy: sub-analyses from celecoxib anti-aromatase neoadjuvant (CAAN) trial

OBJECTIVE

Anti-aromatase therapy is important in the treatment of breast cancer in postmenopausal women but they have effects on the bone mineral density (BMD) and osteoporosis. Cyclooxygenase-2 (COX-2) inhibitors have been shown to be effective in chemoprevention in animal and clinical studies. A proof of principle study was performed to investigate the efficacy of combing anti-aromatase therapy (exemestane) and COX-2 inhibitors neoadjuvantly. The changes in the BMD, bone turnover proteins and quality-of-life (QoL) were analyzed and presented here.

METHOD

82 postmenopausal patients with histologically confirmed invasive hormone-sensitive breast cancers were included for the neoadjuvant therapy (NHT). 30 patients received exemestane (EXE) 25 mg daily and celecoxib (CXB) 400 mg twice daily (group A), 24 patients received EXE 25 mg daily (group B) and 28 patients received letrozole (LET) 2.5 mg daily (group C). The same assigned treatment was intended to continue for 2 years to study the changes in the bone metabolism. BMD of 48 patients were analyzed; 23 belongs to group A, 10 to group B and 15 to group C. The serum bone turnover proteins bone-specific alkaline phosphatase (BAP) and carboxyterminal crosslinked telopeptide of type I collagen (ICTP), were measured with commercially available test kits before treatment, 3 months and 15 months after treatment. Functional Assessment of Cancer Therapy core questionnaire (FACT-G) with its additional breast cancer subscale were performed at baseline, 4, 8, and 12 weeks after NHT.

RESULT

Difference between groups (p=0.007) for BMD at femur was significant. The changes of BMD in group B patients were significantly greater than patients in group A (p=0.011, CI=0.063-0.437), and group C (p=0.003, CI=0.146-0.620). The mean BAP increased from baseline in group B patients but decreased from baseline in group C patients at 3 months and 15 months. No statistical significance was found in the FACT-G scores and FACT-B scores among different groups at baseline, week 4, week 8 and week 12 after NHT. The Breast Cancer Subscale scores in group A patients were significantly higher than that of group C patients (p=0.021). After 4 weeks of NHT, negative changes of FACT-B and FACT-G scores were found in group B and C patients, but there were positive changes in group A patients. Significant differences of FACT-B score (p=0.008) and FACT-G score (p=0.019) were observed at that time point. Article from the Special issue on Targeted Inhibitors.

COX-2 activation is associated with Akt phosphorylation and poor survival in ER-negative, HER2-positive breast cancer

Background

Inducible cyclooxgenase-2 (COX-2) is commonly overexpressed in breast tumors and is a target for cancer therapy. Here, we studied the association of COX-2 with breast cancer survival and how this association is influenced by tumor estrogen and HER2 receptor status and Akt pathway activation.

Methods

Tumor COX-2, HER2 and estrogen receptor α (ER) expression and phosphorylation of Akt, BAD, and caspase-9 were analyzed immunohistochemically in 248 cases of breast cancer. Spearman's correlation and multivariable logistic regression analyses were used to examine the relationship between COX-2 and tumor characteristics. Kaplan-Meier survival and multivariable Cox proportional hazards regression analyses were used to examine the relationship between COX-2 and disease-specific survival.

Results

COX-2 was significantly associated with breast cancer outcome in ER-negative [Hazard ratio (HR) = 2.72; 95% confidence interval (CI), 1.36-5.41; comparing high versus low COX-2] and HER2 overexpressing breast cancer (HR = 2.84; 95% CI, 1.07-7.52). However, the hazard of poor survival associated with increased COX-2 was highest among patients who were both ER-negative and HER2-positive (HR = 5.95; 95% CI, 1.01-34.9). Notably, COX-2 expression in the ER-negative and HER2-positive tumors correlated significantly with increased phosphorylation of Akt and of the two Akt targets, BAD at Ser136 and caspase-9 at Ser196.

Conclusions

Up-regulation of COX-2 in ER-negative and HER2-positive breast tumors is associated with Akt pathway activation and is a marker of poor outcome. The findings suggest that COX-2-specific inhibitors and inhibitors of the Akt pathway may act synergistically as anticancer drugs in the ER-negative and HER2-positive breast cancer subtype.

Changes in protein expression after neoadjuvant use of aromatase inhibitors in primary breast cancer: a proteomic approach to search for potential biomarkers to predict response or resistance

OBJECTIVE

Aromatase inhibitors (AI) have been established as a useful hormonal therapy in hormone receptor-expressing breast carcinoma. However, changes in tumor protein expression after exposure to AIs are not necessarily well understood. These changes may provide insight into how breast carcinomas respond or develop into a state of resistance towards AIs, and lead to the discovery of potential biomarkers to predict treatment responses.

METHODS

Post-menopausal breast cancer patients were recruited to receive 3 months treatment with neoadjuvant AI. Carcinoma tissues were collected before and after the use of AIs and protein expression profiles were compared using two-dimensional gel electrophoresis. Protein spots with different levels of expression were identified using mass spectrometry.

RESULTS

A total of 14 matched pairs of tumor tissues were collected. Both up-regulated and down-regulated proteins were selected and identified as follows: heat shock protein 70 protein 2; Cyclin M3, alpha 1 antichymotrypsin precursor; carbonic anhydrase I, cancer antigen 1; SOBP protein; Rho GDP dissociation inhibitor alpha; glyoxalase I with benzyl glutathione inhibitor; lipid-free human apolipoprotein A-I and RAB4A member RAS oncogene family. Among these proteins, heat shock protein 70 demonstrated the most significant positive correlation with clinical response of the patients.

CONCLUSION

After neoadjuvant use of AI, heat shock protein 70 demonstrated the most consistent phenotypic consistency in both up-regulated and down-regulated protein expression levels among the 14 studied pairs of tumor tissue. Other proteins worthwhile exploring were also identified in this study. These proteins could serve as potential predictors for AI response.

Gene expression profiles as an additional tool to conventional predictive factors to assist in management of early endocrine responsive breast cancer

Cancer treatment has revolutionized from a "one size fits all" approach to a more individualized approach with the advancement of medicine and molecular biology. Several predictive and prognostic factors have been studied and applied to clinical practice to assist clinicians in cancer management. In breast cancer therapeutics, the appearance of biomarkers such as expressions of hormone receptor and human epidermal growth factor (HER) receptors has modified treatment strategies from chemotherapy to molecular-targeted therapy including endocrine therapy and anti-HER therapy. With better understanding of the molecular level of tumorigenesis, cancer pathogenesis and metastases, several novel biomarkers such as cyclo-oxygennase-2 enzyme and tyrosine kinases have been discovered and new anti-cancer agents have been introduced into the currently available treatments. The change has also modified pre-operative treatment for locally advanced and early breast cancers. The neo-adjuvant treatment indeed provides an excellent platform for translational research which is a widely used research method in clinical research. The study of gene and protein expressions from tissue and blood samples collected before, during and after neo-adjuvant treatment provides a lot of keys to decipher the signaling pathways and discover novel biomarkers which are essential for development of new drugs and prediction of the clinical outcome of therapy. The addition of gene expression profiling to conventional predictive factors will give more prognostic information to clinicians for better management of the disease.