Selective cyclooxygenase-2 (COX-2) inhibitors and breast cancer risk

Targeting VEGF signaling for tumor microenvironment remodeling and metastasis inhibition: Therapeutic strategies and insights

The tumor microenvironment (TME) plays a pivotal role in cancer progression and metastasis, with vascular endothelial growth factor (VEGF) signaling serving as a key regulator of tumor angiogenesis and immune evasion. VEGF induces abnormal blood vessel formation, promoting tumor growth, immune suppression, and metastasis through epithelialmesenchymal transition (EMT). As a result, VEGF signaling has become a critical therapeutic target in cancer treatment. This review examines the molecular mechanisms driving VEGF-mediated tumor growth and angiogenesis, with a focus on the interaction between tumor and endothelial cells and the dual role of VEGF in fostering vascularization and immune suppression. Current anti-VEGF therapies, including monoclonal antibodies (e.g., bevacizumab) and tyrosine kinase inhibitors (TKIs), have demonstrated efficacy and have received FDA approval for various cancers; however, therapeutic resistance remains a significant challenge. Strategies to overcome resistance, such as novel VEGF inhibitors, vascular normalization approaches, and combination therapies with immune checkpoint inhibitors, have been explored. Additionally, future directions emphasize the need for personalized approaches to improve treatment efficacy and reduce metastasis. A comprehensive understanding of VEGF signaling in the TME may pave the way for more effective cancer therapies.

NSAID-encapsulated nanoparticles as a targeted therapeutic platform for modulating chronic inflammation and inhibiting cancer progression: a review

Recent advancements in nanotechnology have significantly advanced nanocarrier-mediated drug delivery systems, promoting therapeutic outcomes in mitigating chronic inflammation and cancer. Nanomaterials offer significant advantages over traditional small-molecule drugs, including a high surface-area-to-volume ratio, tunable structural features, and extended bloodstream circulation time. Chronic inflammation is a well-established mechanism for malignant initiation, progression, and metastasis, promoting the potent strategy for cancer prevention and therapy. Numerous studies revealed that nonsteroidal anti-inflammatory drugs (NSAIDs) have the therapeutic ability to manage disease progression via amolerating angiogenesis and inducing apoptosis. However, prolonged intake of NSAIDs is often limited by adverse side-effects and systemic toxicities. The encapsulation of NSAIDs in a nanocarrier have materialized as a dynamic approach to mitigate the limitations by improving pharmacokinetics and pharmacodynamics, reducing off-target effects, and enhancing the drug stability. This review encompasses recent progress in the development of NSAID-based nanotherapeutics, focusing on pivotal mechanisms underlying nanoparticle-mediated drug delivery, such as improved tumor-specific targeting and strategies to overcome drug resistance. The ability of these nano-cargoes to accommodate anti-inflammatory strategies with advanced drug delivery platforms is critically evaluated. This review also highlights the transformative potential of NSAID-encapsulated nanoparticles as a multifaceted therapeutic venue for addressing chronic inflammation and mitigating cancer progression.

Understanding Susceptibility to Breast Cancer: From Risk Factors to Prevention Strategies

Breast cancer is the most common malignancy among women globally, with incidence rates continuing to rise. A comprehensive understanding of its risk factors and the underlying biological mechanisms that drive tumor initiation is essential for developing effective prevention strategies. This review examines key non-modifiable risk factors, such as genetic predisposition, demographic characteristics, family history, mammographic density, and reproductive milestones, as well as modifiable risk factors like exogenous hormone exposure, obesity, diet, and physical inactivity. Importantly, reproductive history plays a dual role, providing long-term protection while temporarily increasing breast cancer risk shortly after pregnancy. Current chemoprevention strategies primarily depend on selective estrogen receptor modulators (SERMs), including tamoxifen and raloxifene, which have demonstrated efficacy in reducing the incidence of estrogen receptor-positive breast cancer but remain underutilized due to adverse effects. Emerging approaches such as aromatase inhibitors, RANKL inhibitors, progesterone antagonists, PI3K inhibitors, and immunoprevention strategies show promise for expanding preventive options. Understanding the interactions between risk factors, hormonal influences, and tumorigenesis is critical for optimizing breast cancer prevention and advancing safer, more targeted chemopreventive interventions.

Significance of non-steroidal anti-inflammatory drugs in the prevention and treatment of cervical cancer

Cervical cancer, ranking as the fourth most common cancer in women globally, is closely linked to chronic inflammation resulting from persistent human papillomavirus (HPV) infection. Chronic inflammation mediated by cyclooxygenase (COX) has been identified as a factor in cancer onset and progression, with HPV oncoproteins E6 and E7 inducing COX activation. Nonsteroidal anti-inflammatory drugs (NSAIDs) have demonstrated the capability to significantly inhibit COX activity, playing a crucial preventive and therapeutic role in various tumors. This paper explores the therapeutic value and potential clinical applications of NSAIDs in cervical cancer by examining the mechanistic interactions between HPV and COX and the carcinogenic effects of COX in cervical cancer.

Celecoxib inhibits NLRP1 inflammasome pathway in MDA-MB-231 Cells

NLRP1 is predominantly overexpressed in breast cancer tissue, and the evaluated activation of NLRP1 inflammasome is associated with tumor growth, angiogenesis, and metastasis. Therefore, targeting NLRP1 activation could be a crucial strategy in anticancer therapy. In this study, we investigated the hypothesis that NLRP1 pathway may contribute to the cytotoxic effects of celecoxib and nimesulide in MDA-MB-231 cells. First of all, IC50 values and inhibitory effects on the colony-forming ability of drugs were evaluated in cells. Then, the alterations in the expression levels of NLRP1 inflammasome components induced by drugs were investigated. Subsequently, the release of inflammatory cytokine IL-1β and the activity of caspase-1 in drug-treated cells were measured. According to our results, celecoxib and nimesulide selectively inhibited the viability of MDA-MB-231 cells. These drugs remarkably inhibited the colony-forming ability of cells. The expression levels of NLRP1 inflammasome components decreased in celecoxib-treated cells, accompanied by decreased caspase-1 activity and IL-1β release. In contrast, nimesulide treatment led to the upregulation of the related protein expressions with unchanged caspase-1 activity and increased IL-1β secretion. Our results indicated that the NLRP1 inflammasome pathway might contribute to the antiproliferative effects of celecoxib in MDA-MB-231 cells but is not a crucial mechanism for nimesulide.

Association of COX-inhibitors with cancer patients' survival under chemotherapy and radiotherapy regimens: a real-world data retrospective cohort analysis

Introduction

We conducted an extensive, sex-oriented real-world data analysis to explore the impact and safety of non-steroidal anti-inflammatory drugs (NSAIDs) and selective COX-2 inhibitors (coxibs) on cancer treatment outcomes. This is particularly relevant given the role of the COX-2/PGE2 pathway in tumor cell resistance to chemotherapy and radiotherapy.

Methods

The study applied a retrospective cohort design utilizing the TriNetX research database consisting of patients receiving cancer treatment in 2008-2022. The treated cohorts included patients who were prescribed with coxibs, aspirin or ibuprofen, while individuals in the control cohort did not receive these medicines during their cancer treatment. A 1:1 propensity score matching technique was used to balance the baseline characteristics in the treated and control cohorts. Then, Cox proportional hazards regression and logistic regression were applied to assess the mortality and morbidity risks among patient cohorts in a 5-year follow-up period.

Results

Use of coxibs (HR, 0.825; 95% CI 0.792-0.859 in females and HR, 0.884; 95% CI 0.848-0.921 in males) and ibuprofen (HR, 0.924; 95% CI 0.903-0.945 in females and HR, 0.940; 95% CI 0.917-0.963 in males) were associated with improved survival. Female cancer patients receiving aspirin presented increased mortality (HR, 1.078; 95% CI 1.060-1.097), while male cancer patients also had improved survival when receiving aspirin (HR, 0.966; 95% CI 0.951-0.980). Cancer subtype specific analysis suggests coxibs and ibuprofen correlated with survival, though ibuprofen and aspirin increased emergency department visits' risk. Secondary analyses, despite limited by small cohort sizes, suggest that COX inhibition post-cancer diagnosis may benefit patients with specific cancer subtypes.

Discussion

Selective COX-2 inhibition significantly reduced mortality and emergency department visit rates. Further clinical trials are needed to determine the optimal conditions for indication of coxibs as anti-inflammatory adjuvants in cancer treatment.

Enhancing therapeutic efficacy in triple-negative breast cancer and melanoma: synergistic effects of modulated electro-hyperthermia (mEHT) with NSAIDs especially COX-2 inhibition in in vivo models

Triple-negative breast cancer (TNBC) is a leading cause of cancer mortality and lacks modern therapy options. Modulated electro-hyperthermia (mEHT) is an adjuvant therapy with demonstrated clinical efficacy for the treatment of various cancer types. In this study, we report that mEHT monotherapy stimulated interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) expression, and consequently cyclooxygenase 2 (COX-2), which may favor a cancer-promoting tumor microenvironment. Thus, we combined mEHT with nonsteroid anti-inflammatory drugs (NSAIDs): a nonselective aspirin, or the selective COX-2 inhibitor SC236, in vivo. We demonstrate that NSAIDs synergistically increased the effect of mEHT in the 4T1 TNBC model. Moreover, the strongest tumor destruction ratio was observed in the combination SC236 + mEHT groups. Tumor damage was accompanied by a significant increase in cleaved caspase-3, suggesting that apoptosis played an important role. IL-1β and COX-2 expression were significantly reduced by the combination therapies. In addition, a custom-made nanostring panel demonstrated significant upregulation of genes participating in the formation of the extracellular matrix. Similarly, in the B16F10 melanoma model, mEHT and aspirin synergistically reduced the number of melanoma nodules in the lungs. In conclusion, mEHT combined with a selective COX-2 inhibitor may offer a new therapeutic option in TNBC.

The Potential Preventive and Therapeutic Roles of NSAIDs in Prostate Cancer

Prostate cancer (PC) is the second most common type of cancer and the leading cause of death among men worldwide. Preventing the progression of cancer after treatments such as radical prostatectomy, radiation therapy, and hormone therapy is a major concern faced by prostate cancer patients. Inflammation, which can be caused by various factors such as infections, the microbiome, obesity and a high-fat diet, is considered to be the main cause of PC. Inflammatory cells are believed to play a crucial role in tumor progression. Therefore, nonsteroidal anti-inflammatory drugs along with their effects on the treatment of inflammation-related diseases, can prevent cancer and its progression by suppressing various inflammatory pathways. Recent evidence shows that nonsteroidal anti-inflammatory drugs are effective in the prevention and treatment of prostate cancer. In this review, we discuss the different pathways through which these drugs exert their potential preventive and therapeutic effects on prostate cancer.

Host-Related Factors in the Interplay among Inflammation, Immunity and Dormancy in Breast Cancer Recurrence and Prognosis: An Overview for Clinicians

A significant proportion of patients treated for early breast cancer develop medium-term and late distant recurrence. The delayed manifestation of metastatic disease is defined as "dormancy". This model describes the aspects of the clinical latency of isolated metastatic cancer cells. Dormancy is regulated by extremely complex interactions between disseminated cancer cells and the microenvironment where they reside, the latter in turn influenced directly by the host. Among these entangled mechanisms, inflammation and immunity may play leading roles. This review is divided into two parts: the first describes the biological underpinnings of cancer dormancy and the role of the immune response, in particular, for breast cancer; the second provides an overview of the host-related factors that may influence systemic inflammation and immune response, subsequently impacting the dynamics of breast cancer dormancy. The aim of this review is to provide physicians and medical oncologists a useful tool to understand the clinical implications of this relevant topic.

Potential of Anti-inflammatory Molecules in the Chemoprevention of Breast Cancer

Breast cancer is a global issue, affecting greater than 1 million women per annum. Over the past two decades, there have been numerous clinical trials involving the use of various pharmacological substances as chemopreventive agents for breast cancer. Various pre-clinical as well as clinical studies have established numerous anti-inflammatory molecules, including nonsteroidal anti-inflammatory drugs (NSAIDs) and dietary phytochemicals as promising agents for chemoprevention of several cancers, including breast cancer. The overexpression of COX-2 has been detected in approximately 40% of human breast cancer cases and pre-invasive ductal carcinoma in-situ lesions, associated with aggressive elements of breast cancer such as large size of the tumour, ER/PR negative and HER-2 overexpression, among others. Anti-inflammatory molecules inhibit COX, thereby inhibiting the formation of prostaglandins and inhibiting nuclear factor-κBmediated signals (NF-kB). Another probable explanation entails inflammation-induced degranulation, with the production of angiogenesis-regulating factors, such as vascular endothelial growth factor, which can be possibly regulated by anti-inflammatory molecules. Apart from NSAIDS, many dietary phytochemicals have the ability to decrease, delay, or stop the progression and/or incidence of breast cancer by their antioxidant action, regulating inflammatory and proliferative cell signalling pathways as well as inducing apoptosis. The rapid progress in chemoprevention research has also established innovative strategies that can be implemented to prevent breast cancer. This article gives a comprehensive overview of the recent advancements in using antiinflammatory molecules in the chemoprevention of breast cancer along with their mechanism of action, supported by latest preclinical and clinical data. The merits of anti-inflammatory chemopreventive agents in the prevention of cardiotoxicity have been described. We have also highlighted the ongoing research and advancements in improving the efficacy of using antiinflammatory molecules as chemopreventive agents.

Current regular aspirin use and mammographic breast density: a cross-sectional analysis considering concurrent statin and metformin use

PURPOSE

The nonsteroidal anti-inflammatory drug aspirin is an agent of interest for breast cancer prevention. However, it is unclear if aspirin affects mammographic breast density (MBD), a marker of elevated breast cancer risk, particularly in the context of concurrent use of medications indicated for common cardiometabolic conditions, which may also be associated with MBD.

METHODS

We used data from the New York Mammographic Density Study for 770 women age 40-60 years old with no history of breast cancer. We evaluated the association between current regular aspirin use and MBD, using linear regression for continuous measures of absolute and percent dense areas and absolute non-dense area, adjusted for body mass index (BMI), sociodemographic and reproductive factors, and use of statins and metformin. We assessed effect modification by BMI and reproductive factors.

RESULTS

After adjustment for co-medication, current regular aspirin use was only positively associated with non-dense area (β = 18.1, 95% CI: 6.7, 29.5). Effect modification by BMI and parity showed current aspirin use to only be associated with larger non-dense area among women with a BMI ≥ 30 (β = 28.2, 95% CI: 10.8, 45.7), and with lower percent density among parous women (β = -3.3, 95% CI: -6.4, -0.3).

CONCLUSIONS

Independent of co-medication use, current regular aspirin users had greater non-dense area with stronger estimates for women with higher BMI. We found limited support for an association between current aspirin use and mammographically dense breast tissue among parous women.

NSAIDs and Cancer Resolution: New Paradigms beyond Cyclooxygenase

Acute inflammation or resolved inflammation is an adaptive host defense mechanism and is self-limiting, which returns the body to a state of homeostasis. However, unresolved, uncontrolled, or chronic inflammation may lead to various maladies, including cancer. Important evidence that links inflammation and cancer is that nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, reduce the risk and mortality from many cancers. The fact that NSAIDs inhibit the eicosanoid pathway prompted mechanistic drug developmental work focusing on cyclooxygenase (COX) and its products. The increased prostaglandin E2 levels and the overexpression of COX-2 in the colon and many other cancers provided the rationale for clinical trials with COX-2 inhibitors for cancer prevention or treatment. However, NSAIDs do not require the presence of COX-2 to prevent cancer. In this review, we highlight the effects of NSAIDs and selective COX-2 inhibitors (COXIBs) on targets beyond COX-2 that have shown to be important against many cancers. Finally, we hone in on specialized pro-resolving mediators (SPMs) that are biosynthesized locally and, in a time, -dependent manner to promote the resolution of inflammation and subsequent tissue healing. Different classes of SPMs are reviewed, highlighting aspirin's potential in triggering the production of these resolution-promoting mediators (resolvins, lipoxins, protectins, and maresins), which show promise in inhibiting cancer growth and metastasis.

Use of nonsteroidal anti-inflammatory drugs and breast cancer risk in a prospective cohort of postmenopausal women

BACKGROUND

Although anti-inflammatory agents could theoretically have anticancer properties, results from cohort studies on nonsteroidal anti-inflammatory drugs (NSAIDs) and breast cancer (BC) risk are inconsistent.

METHODS

We investigated the association between NSAID use and BC incidence in the French E3N prospective cohort, which includes 98,995 women born between 1925 and 1950 and insured by a health insurance plan that covers mostly teachers. Self-reported information on lifestyle and medical history has been collected biennially by questionnaires and matched with data from a drug reimbursement database covering the period 2004-2014. Women who self-reported current NSAID use in the 2000 or 2002 questionnaires or with at least two reimbursements in any previous 3-month period were defined as exposed to NSAIDs. Multivariable Cox regression models were used to estimate hazard ratios (HRs) for the association of NSAID use with BC risk.

RESULTS

In the current analysis, 62,512 postmenopausal women were followed between 2004 and 2014 (9 years on average, starting at a mean age of 63 years; 2864 incident BC). In multivariable models, there was no statistically significant association between NSAID use and BC risk [HR = 1.00 (0.92-1.08), compared with non-exposed women]. The NSAID-BC associations did not differ by NSAID types, BC subtypes, risk factors, and comorbidities, nor by duration and dose of use. However, a statistically significant interaction was observed by proton pump inhibitor (PPI) drug use (Pinteraction = 0.01) whereby a decreased risk of BC with NSAID use was only observed among women who also used PPI before.

CONCLUSION

Only women who used NSAIDs after having used PPI had a lower risk of BC. This result is novel and requires replication in other studies.

Human cytomegalovirus infection is correlated with enhanced cyclooxygenase-2 and 5-lipoxygenase protein expression in breast cancer

Purpose

While enhanced expression of cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LO) and their derived metabolites is associated with breast cancer (BC) risk, the precise link between BC carcinogenesis and enhanced inflammatory activity remains to be clarified. Human Cytomegalovirus (HCMV) may induce expression of COX-2 and 5-LO and is frequently found in breast cancer biopsies. Thus, we investigated whether there is an association between HCMV proteins and expression of COX-2 and 5-LO in human BC tissue and BC cell lines.

Materials and methods

Paraffin embedded biopsies obtained from 49 patients with breast cancer and 26 tissue samples from adjacent, benign breast tissues were retrospectively examined for HCMV-immediate early (IE), HCMV-Late (LA), COX-2, and 5-LO proteins by immunohistochemistry. In vitro, uninfected and HCMV-infected BC cell lines were examined for COX-2 and 5-LO transcripts and proteins by PCR and flow cytometry.

Results

Extensive expression of COX-2, 5-LO and HCMV-IE proteins were preferentially detected in BC samples. We found a statistically significant concordant correlation between extensive HCMV-IE and COX-2 (P < 0.0001) as well as with HCMV-IE and 5-LO (P = 0.0003) in infiltrating BC. In vitro, HCMV infection induced COX-2 and 5-LO transcripts and COX-2 proteins in MCF-7 cells (P =0.008, P =0.018, respectively). In MDA-MB-231 cells that already had high base line levels of COX-2 expression, HCMV induced both COX-2 and 5-LO proteins but not transcripts.

Conclusion

Our findings demonstrate a significant correlation between extensive HCMV-IE protein expression and overexpression of COX-2 and 5-LO in human breast cancer.

Electronic supplementary material

The online version of this article (10.1007/s00432-019-02946-8) contains supplementary material, which is available to authorized users.

Protective effect of Astragaloside IV to inhibit thiram-induced tibial dyschondroplasia

Tibial dyschondroplasia (TD) is most the common tibiotarsal bone disease in rapidly growing birds throughout the world. There is accumulating evidence that COX-2 abnormal expression in tibia plays an important role in TD progression. So, the regulation of COX-2 is an ever more appealing target for therapeutic intervention in TD. Astragaloside IV has an indispensable role in maintaining COX-2 expression in many diseases. So, we designed this study to use Astragaloside IV (AST-IV) against TD-affected chickens. A total of 180 Arbor Acres chickens were randomly divided in the control group, TD group, and Astr (AST-IV-treated chickens) group. During the experiment, mortality, feed conversion ratio, physiological changes, biochemical criterion, liver antioxidant enzymes, and gene expression of COX-2 were examined in all the chicken groups at various days. The results showed that AST-IV administration restored the growth performance and tibia lesions and decreased the mortality as compared with TD chickens. The biochemical criterion (ALP, AST, and ALT) of serum and liver antioxidant enzymes (SOD, GSH-Px, MDA, and T-AOC) improved after the administration of AST-IV. The COX-2 gene was upregulated significantly (P < 0.05) in TD chickens. Whereas, AST-IV treatment downregulated both gene and protein expression of COX-2 significantly (P < 0.05) in TD-affected chickens. AST-IV recovered tibial dyschondroplasia chickens by increasing the growth performance, ameliorating tibial cartilage damage, and decreasing COX-2 expression. In conclusion, AST-IV can be used to prevent thiram-induced TD in chickens.

Nonaspirin NSAIDs and contralateral breast cancer risk

Laboratory studies suggest that inhibition of the cyclooxygenase (COX)-2 enzymes inhibits breast cancer development. We aimed to evaluate whether postdiagnosis use of COX-2 selective or other nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs) reduce the risk of contralateral breast cancer (CBC) among Danish breast cancer patients. From the clinical database of the Danish Breast Cancer Group, we identified 52,723 women diagnosed with breast cancer between 1996 and 2012. Data on nonaspirin NSAID use, CBC and potential confounding variables were obtained from nationwide registries. We defined postdiagnosis use (two or more prescriptions) as a time-varying covariate with a one-year lag. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for CBC associated with nonaspirin NSAID use. During a median follow-up of 4.8 years (interquartile range: 2.3-9 years), 1,444 patients were diagnosed with CBC. Overall, postdiagnosis use of nonaspirin NSAID was associated with an adjusted HR for CBC of 0.98 (95% CI: 0.87-1.11). The HRs did not vary substantially with duration or intensity of nonaspirin NSAID use. Moreover, similar associations were found for COX-2 selective (HR: 1.02; 95% CI: 0.85-1.23) and nonselective (HR: 0.96; 95% CI: 0.82-1.13) nonaspirin NSAIDs. In conclusion, our nationwide cohort study of breast cancer patients does not suggest a reduced risk of CBC with nonaspirin NSAID use regardless of the COX-2 selectivity.

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.

EP4 as a Therapeutic Target for Aggressive Human Breast Cancer

G-protein-coupled receptors (GPCRs, also called seven-transmembrane or heptahelical receptors) are a superfamily of cell surface receptor proteins that bind to many extracellular ligands and transmit signals to an intracellular guanine nucleotide-binding protein (G-protein). When a ligand binds, the receptor activates the attached G-protein by causing the exchange of Guanosine-5′-triphosphate (GTP) for guanosine diphosphate (GDP). They play a major role in many physiological functions, as well as in the pathology of many diseases, including cancer progression and metastasis. Only a few GPCR members have been exploited as targets for developing drugs with therapeutic benefit in cancer. Present review briefly summarizes the signaling pathways utilized by the EP (prostaglandin E receptor) family of GPCR, their physiological and pathological roles in carcinogenesis, with special emphasis on the roles of EP4 in breast cancer progression. We make a case for EP4 as a promising newer therapeutic target for treating breast cancer. We show that an aberrant over-expression of cyclooxygenase (COX)-2, which is an inflammation-associated enzyme, occurring in 40–50% of breast cancer patients leads to tumor progression and metastasis due to multiple cellular events resulting from an increased prostaglandin (PG) E2 production in the tumor milieu. They include inactivation of host anti-tumor immune cells, such as Natural Killer (NK) and T cells, increased immuno-suppressor function of tumor-associated macrophages, promotion of tumor cell migration, invasiveness and tumor-associated angiogenesis, due to upregulation of multiple angiogenic factors including Vascular Endothelial Growth Factor (VEGF)-A, increased lymphangiogenesis (due to upregulation of VEGF-C/D), and a stimulation of stem-like cell (SLC) phenotype in cancer cells. All of these events were primarily mediated by activation of the Prostaglandin (PG) E receptor EP4 on tumor or host cells. We show that selective EP4 antagonists (EP4A) could mitigate all of these events tested with cells in vitro as well as in vivo in syngeneic COX-2 expressing mammary cancer bearing mice or immune-deficient mice bearing COX-2 over-expressing human breast cancer xenografts. We suggest that EP4A can avoid thrombo-embolic side effects of long term use of COX-2 inhibitors by sparing cardio-protective roles of PGI2 via IP receptor activation or PGE2 via EP3 receptor activation. Furthermore, we identified two COX-2/EP4 induced oncogenic and SLC-stimulating microRNAs—miR526b and miR655, one of which (miR655) appears to be a potential blood biomarker in breast cancer patients for monitoring SLC-ablative therapies, such as with EP4A. We suggest that EP4A will likely produce the highest benefit in aggressive breast cancers, such as COX-2 expressing triple-negative breast cancers, when combined with other newer agents, such as inhibitors of programmed cell death (PD)-1 or PD-L1.

Regular and low-dose aspirin, other non-steroidal anti-inflammatory medications and prospective risk of HER2-defined breast cancer: the California Teachers Study

BACKGROUND

Regular users of aspirin may have reduced risk of breast cancer. Few studies have addressed whether risk reduction pertains to specific breast cancer subtypes defined jointly by hormone receptor (estrogen and progesterone receptor) and human epidermal growth factor receptor 2 (HER2) expression. This study assessed the prospective risk of breast cancer (overall and by subtype) according to use of aspirin and other non-steroidal anti-inflammatory medications (NSAIDs) in a cohort of female public school professionals in California.

METHODS

In 1995 - 1996, participants in the California Teachers Study completed a baseline questionnaire on family history of cancer and other conditions, use of NSAIDs, menstrual and reproductive history, self-reported weight and height, living environment, diet, alcohol use, and physical activity. In 2005-2006, 57,164 participants provided some updated information, including use of NSAIDs and 1457 of these participants developed invasive breast cancer before January 2013. Multivariable Cox proportional hazards regression models provided hazard rate ratios (HRR) for the association between NSAID use and risk of invasive breast cancer as well as hormone receptor- and HER2-defined subtypes.

RESULTS

Developing breast cancer was associated inversely with taking three or more tablets of low-dose aspirin per week (23% of participants). Among women reporting this exposure, the HRR was 0.84 (95% confidence interval (CI) 0.72-0.98) compared to those not taking NSAIDs and this was particularly evident in women with the hormone receptor-positive/HER2-negative subtype (HRR = 0.80, 95% CI 0.66-0.96). Use of three or more tablets of "other" NSAIDs was marginally associated with lower risk of breast cancer (HRR = 0.79, 95% CI 0.62-1.00). Other associations with NSAIDs were generally null.

CONCLUSION

Our observation of reduced risk of breast cancer, among participants who took three or more tablets of low-dose aspirin weekly, is consistent with other reports looking at aspirin without differentiation by dose. This is the first report to suggest that the reduction in risk occurs for low-dose aspirin and not for regular-dose aspirin and only among women with the hormone receptor-positive/HER2-negative subtype. This preliminary study builds on previous knowledge and further supports the need for formal cancer chemoprevention studies of low-dose aspirin.

Parecoxib inhibits glioblastoma cell proliferation, migration and invasion by upregulating miRNA-29c

Glioblastoma (GBM) is one of the most lethal brain cancers worldwide, and there is an urgent need for development of novel therapeutic approaches. Parecoxib is a well-known cyclooxygenase-2 (COX-2) inhibitor, and had already been developed for postoperative analgesia with high efficacy and low adverse reaction. A recent study has suggested that parecoxib potently enhances immunotherapeutic efficacy of GBM, but its effects on GBM growth, migration and invasion have not previously been studied. In the present study, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and BrdU (5-bromo-2-deoxyuridine) incorporation assays were used to evaluate the cell proliferation of GBM cells. Wound-healing and transwell assays were preformed to analyze GBM cell migration and invasion, respectively. The results suggested that parecoxib inhibits cell proliferation, migration and invasion of GBM cells in a dose-dependent manner. RT-qPCR (real-time quantitative PCR) analysis demonstrated that miRNA-29c can be significantly induced by parecoxib. Furthermore, our data suggests that a miRNA-29c inhibitor can significantly attenuate parecoxib's effect on proliferation, migration and invasion of GBM. In conclusion, the present study suggests that parecoxib inhibits GBM cell proliferation, migration and invasion by upregulating miRNA-29c.

Comparative Evaluation of Nimesulide-Loaded Nanoparticles for Anticancer Activity Against Breast Cancer Cells

Recent clinical and epidemiological researches have declared that non-steroidal anti-inflammatory agents may display as antineoplastic agents and indicate pro-apoptotic and antiproliferative effects on cancer cells. The major purpose of this research was to develop a novel poly(ethyleneglycol)-block-poly(ε-caprolactone) (PEG-b-PCL) nano-sized particles encapsulated with nimesulide (NMS), a selective COX-2 inhibitor, and to evaluate its anticancer activity against MCF-7 breast cancer cells. NMS-encapsulated PEG-b-PCL nanoparticles were fabricated using three different production techniques: (i) by emulsion-solvent evaporation using a high shear homogenizer, (ii) by emulsion-solvent evaporation using an ultrasonicator, and (iii) by nanoprecipitation. Nanoparticles were evaluated with respect to the entrapment efficiency, size characteristics, drug release rates, thermal behavior, cell viability assays, and apoptosis. The resulting nanoparticles were found to be spherical shapes with negative surface charges. The average diameter of all nanoparticles ranged between 148.5 and 307.2 nm. In vitro release profiles showed that all nanoparticles exhibited a biphasic release pattern. NMS-loaded PEG-b-PCL nanoparticles demonstrated significant anticancer activity against MCF-7 breast cancer cells in a dose-dependent manner, and the effects of nanoparticles on cell proliferation were significantly affected by the preparation techniques. The nanoparticles developed in this work displayed higher potential for the NMS delivery against breast cancer treatment for the future.

Valdecoxib Recovers the Lipid Composition, Order and Dynamics in Colon Cancer Cell Lines Independent of COX-2 Expression: An ATR-FTIR Spectroscopy Study

Prostanoids play an important role in a variety of physiological and pathophysiological processes including inflammation and cancer. The rate-limiting step in the prostanoid biosynthesis pathway is catalyzed by cyclooxygenases (COXs). Aberrant expression of the inducible isoform COX-2 plays a significant role in colon cancer initiation and progression. In this study, we have hypothesized that COX-2 specific inhibitors such as Valdecoxib (VLX), being highly hydrophobic, may alter biophysical properties of cellular lipids. In this study, COX-2 expressing (HT29) and COX-2 non-expressing (SW620) colon cancer cell lines were treated with VLX and examined using attenuated total reflection infrared spectroscopy. The results revealed that VLX treatment decreased lipid fluidity in the cells irrespective of COX-2 expression status and affected order parameters of the lipids in both cell lines. Cluster analysis also indicated that the spectral differences between the two cell lines are profound and could be successfully differentiated. Valdecoxib treatment could enhance the composition, order and dynamics of the lipids of colon cancer cells independently of its COX-2 inhibitory mechanism. Valdecoxib has therapeutic effects upon colon cancer, therefore it can be used as an adjuvant and/or chemopreventive agent for colon cancer.

Use of acetaminophen in relation to the occurrence of cancer: a review of epidemiologic studies

Acetaminophen has several pharmacologic properties that suggest it could be carcinogenic in human beings. A number of epidemiologic studies have been conducted to examine whether use of acetaminophen actually predisposes to the occurrence of one or more forms of cancer. There are inherent limitations to many of these studies, including the inaccurate identification of users and nonusers of acetaminophen, relatively short follow-up for cancer incidence, and the potential for confounding by indication. The present manuscript reviews the results of epidemiologic studies of acetaminophen use in relation to cancer incidence published through the end of 2015. The limitations of the underlying studies notwithstanding, some interim conclusions can be reached. For all but several forms of cancer, there is no suggestion that persons who have taken acetaminophen are at altered risk, even persons who have consumed a large quantity of the drug or those who have taken it for an extended duration. While in some studies the incidence of renal cell carcinoma has been observed to be increased among acetaminophen users, several other studies have failed to observe any such association; the reason for the discrepant findings is unclear. Some of the small number of studies that have presented data on the incidence of lymphoma, leukemia, and plasma cell disorders have found the risk to be modestly higher in users than nonusers of acetaminophen, but the results of other studies of these malignancies will be needed to gauge the possible role of publication bias as the basis for the positive results.

Nonsteroidal anti-inflammatory drugs, statins, and pancreatic cancer risk: a population-based case-control study

PURPOSE

Studies suggest that aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and statins may reduce risk of some cancers. However, findings have been conflicting as to whether these agents reduce the risk of pancreatic cancer.

METHODS

We used data from the Queensland Pancreatic Cancer Study, a population-based case-control study. In total, 704 cases and 711 age- and sex-matched controls were recruited. Participants completed an interview in which they were asked about history of NSAID and statin use. We included 522 cases and 653 controls who had completed the medication section of the interview in this analysis. Unconditional multivariable logistic regression was used to estimate associations between medication use and pancreatic cancer.

RESULTS

We found no consistent evidence of an association between use of NSAIDs or statins and risk of pancreatic cancer. There was some suggestion of a protective effect in infrequent users of selective COX-2 inhibitors, but no association in more frequent users. We did not find evidence of protective effects in analyses stratified by sex, smoking status, time between diagnosis and interview, or presence/absence of metastases.

CONCLUSIONS

Overall, our results do support the hypothesis that use of NSAIDs or statins may reduce the odds of developing pancreatic cancer.

Use of non-steroidal anti-inflammatory drugs and risk of breast cancer: The Spanish Multi-Case-control (MCC) study

Background

The relationship between non-steroidal anti-inflammatory drug (NSAID) consumption and breast cancer has been repeatedly studied, although the results remain controversial. Most case-control studies reported that NSAID consumption protected against breast cancer, while most cohort studies did not find this effect. Most studies have dealt with NSAIDs as a whole group or with specific drugs, such aspirin, ibuprofen, or others, but not with NSAID subgroups according to the Anatomical Therapeutic Chemical Classification System; moreover, scarce attention has been paid to their effect on different tumor categories (i.e.: ductal/non-ductal, stage at diagnosis or presence of hormonal receptors).

Methods

In this case-control study, we report the NSAID – breast cancer relationship in 1736 breast cancer cases and 1895 healthy controls; results are reported stratifying by the women’s characteristics (i.e.: menopausal status or body mass index category) and by tumor characteristics.

Results

In our study, NSAID use was associated with a 24 % reduction in breast cancer risk (Odds ratio [OR] = 0.76; 95 % Confidence Interval [CI]: 0.64–0.89), and similar results were found for acetic acid derivatives, propionic acid derivatives and COXIBs, but not for aspirin. Similar results were found in postmenopausal and premenopausal women. NSAID consumption also protected against hormone + or HER2+ cancers, but not against triple negative breast cancers. The COX-2 selectivity showed an inverse association with breast cancer (i.e. OR < 1), except in advanced clinical stage and triple negative cancers.

Conclusion

Most NSAIDs, but not aspirin, showed an inverse association against breast cancer; this effect seems to be restricted to hormone + or HER2+ cancers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2692-4) contains supplementary material, which is available to authorized users.

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.

Dual inhibition of COX-2/5-LOX blocks colon cancer proliferation, migration and invasion in vitro

Inflammation is emerging as a new hallmark of cancer. Arachidonic acid (AA) metabolism, the family of cyclooxygenases (COXs) and lipoxygenase (LOX) play important roles in AA-related inflammatory cascades. In 94 colorectal cancer samples collected from the Han population, the immunohistochemical results indicated that 68% of the patients with colorectal cancer had a co-expression of both COX-2 and 5-LOX, while both displayed low expression in the matched normal tissues. In cell lines, three colorectal cancer cell lines exhibited high expression of COX-2 and 5-LOX. During stable silencing of the expression of COX-2 or 5-LOX in LoVo cancer cells, we found that downregulation of either COX-2 or 5-LOX significantly diminished the growth, migration and invasion of the colon cancer cells and specifically, downregulation of COX-2 could elicit upregulation of 5-LOX protein and vice versa. The above results suggested that the simultaneous blocking of COX-2 and 5-LOX activity may bring more potential benefits in managing the progression of colon cancer. Therefore, we sought to explore the effectiveness of a dual COX-2/5-LOX inhibitor darbufelone on the proliferation, migration, invasion and apoptosis of colon cancer cells, as well as the underlying mechanism of action. The results indicated that darbufelone significantly decreased the proliferative and invasive abilities of the colon cancer cells, in a dose-dependent manner. During the study of the related mechanisms, we found an upregulation of p27 and downregulation of cyclin D1 as well as CDK4 after darbufelone treatment, which indicated that darbufelone could arrest the cell cycle of LoVo cells at the G0/G1 phase. Furthermore, the activation of caspase-3 and -9, upregulation of Bax and downregulation of Bcl-2 demonstrated the occurrence of apoptosis by darbufelone. Finally, darbufelone also prevented the migration and invasion of LoVo cells, which may be ascribed to the upregulation of E-cadherin and ZO-1. In summary, our data suggest that the inhibition of both COX-2/5-LOX may be an effective therapeutic approach for colon cancer management, particularly for those patients with high expression of COX-2/5-LOX.

Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density

Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast cancer risk, and was increased in stromal cells in high MD tissues in one study. Our study assessed differential Cox-2 expression in epithelial and stromal cells in paired samples of high and low MD human breast tissue, and in a validated xenograft biochamber model of MD. We also examined the effects of endocrine treatment upon Cox-2 expression in high and low MD tissues in the MD xenograft model. Paired high and low MD human breast tissue samples were immunostained for Cox-2, then assessed for differential expression and staining intensity in epithelial and stromal cells. High and low MD human breast tissues were separately maintained in biochambers in mice treated with Tamoxifen, oestrogen or placebo implants, then assessed for percentage Cox-2 staining in epithelial and stromal cells. Percentage Cox-2 staining was greater for both epithelial (p = 0.01) and stromal cells (p < 0.0001) of high compared with low MD breast tissues. In high MD biochamber tissues, percentage Cox-2 staining was greater in stromal cells of oestrogen-treated versus placebo-treated tissues (p = 0.05).

Effect of COX-2 inhibitors and other non-steroidal inflammatory drugs on breast cancer risk: a meta-analysis

Evidence on non-steroidal anti-inflammatory drugs (NSAID) use and breast cancer risk shows a slightly protective effect of these drugs, but previous studies lack randomized clinical trial results and present high heterogeneity in exposure measurement. This systematic review and meta-analysis widens the knowledge about NSAID use and breast cancer risk, updating the information from the last meta-analysis, focusing on evidence on specific effects of COX-2 inhibitors and differential expression patterns of hormonal receptors. A PubMed-database search was conducted to include all entries published with the keywords "BREAST CANCER NSAID ANTI-INFLAMMATORY" until 10/24/2013 providing original results from cohort studies, case-control studies, or randomized clinical trials with at least one reported relative risk (RR) or odds ratio (OR) on the association between any NSAID use and incidence of invasive breast cancer. This resulted in 49 publications, from which the information was retrieved about type of study, exposure characteristics, breast cancer characteristics, and breast cancer-NSAID association. Meta-analyses were performed separately for case-control and cohort studies and for different hormone-receptor status. NSAID use reduced invasive breast cancer risk by about 20 %. A similar effect was found for aspirin, acetaminophen, COX-2 inhibitors and, to a lesser extent, ibuprofen. The effect of aspirin was similar in preventing hormone-receptor-positive breast cancer. This meta-analysis suggests a slightly protective effect of NSAIDs-especially aspirin and COX-2 inhibitors- against breast cancer, which seems to be restricted to ER/PR+tumors.

Expression of integrin α3β1 and cyclooxygenase-2 (COX2) are positively correlated in human breast cancer

BACKGROUND

Expression of integrin α3β1 is associated with tumor progression, metastasis, and poor prognosis in several cancers, including breast cancer. Moreover, preclinical studies have revealed important pro-tumorigenic and pro-metastatic functions for this integrin, including tumor growth, survival, invasion, and paracrine induction of angiogenesis. Our previously published work in a preclinical breast cancer model showed that integrin α3β1 promotes expression of cyclooxygenase-2 (COX2/PTGS2), a known driver of breast cancer progression. However, the clinical significance of this regulation was unknown. The objective of the current study was to assess the clinical relevance of the relationship between integrin α3β1 and COX2 by testing for their correlated expression among various forms of human breast cancer.

METHODS

Immunohistochemistry was performed to assess co-expression of α3 and COX2 in specimens of human invasive ductal carcinoma (IDC), either on a commercial tissue microarray (n = 59 samples) or obtained from Albany Medical Center archives (n = 68 samples). Immunostaining intensity for the integrin α3 subunit or COX2 was scored, and Spearman's rank correlation coefficient analysis was performed to assess their co-expression across and within different tumor subtypes or clinicopathologic criteria.

RESULTS

Although expression of integrin α3 or COX2 varied among clinical IDC samples, a statistically significant, positive correlation was detected between α3 and COX2 in both tissue microarrays (r(s) = 0.49, p < 0.001, n = 59) and archived samples (r(s) = 0.59, p < 0.0001, n = 68). In both sample sets, this correlation was independent of hormone receptor status, histological grade, or disease stage.

CONCLUSIONS

COX2 and α3 are correlated in IDC independently of hormone receptor status or other clinicopathologic features, supporting the hypothesis that integrin α3β1 is a determinant of COX2 expression in human breast cancer. These results support the clinical relevance of α3β1-dependent COX2 gene expression that we reported previously in breast cancer cells. The findings also suggest that COX2-positive breast carcinomas of various subtypes might be vulnerable to therapeutic strategies that target α3β1, and that α3 expression might serve as an independent prognostic biomarker.

Neuronal and nonneuronal COX-2 expression confers neurotoxic and neuroprotective phenotypes in response to excitotoxin challenge

Treating acute brain injuries with COX-2 inhibitors can produce both neuroprotective and neurotoxic effects. This study investigated the role of COX-2 in modulating acute brain injury induced by excitotoxic neural damage. Intrastriatal injection of excitotoxin (RS)-(tetrazole-5yl) glycine elicited COX-2 expression in two distinct groups of cells. cortical neurons surrounding the lesion and vascular cells in the lesion core. The vascular COX-2 was expressed in two cell types, endothelial cells and monocytes. Selective deletion of COX-2 in vascular cells in Tie2Cre Cox-2(flox/flox) mice did not affect the induction of COX-2 in neurons after the excitotoxin injection but resulted in increased lesion volume, indicating a neuroprotective role for the COX-2 expressed in the vascular cells. Selective deletion of monocyte COX-2 in LysMCre Cox-2(flox/flox) mice did not reduce COX-2-dependent neuroprotection, suggesting that endothelial COX-2 is sufficient to confer neuroprotection. Pharmacological inhibition of COX-2 activity in Tie2Cre Cox-2(flox/flox) mice reduced lesion volume, indicating a neurotoxic role for the COX-2 expressed in neurons. Furthermore, COX-2-dependent neurotoxicity was mediated, at least in part, via the activation of the EP1 receptor. These results show that Cox-2 expression induced in different cell types can confer opposite effects.

Concurrent celecoxib with 5-fluorouracil/epirubicin/cyclophosphamide followed by docetaxel for stages II - III invasive breast cancer: the OOTR-N001 study

OBJECTIVES

This prospective study aimed at investigating the efficacy and safety of the concurrent use of celecoxib (CXB) with 5-fluorouracil, epirubicin and cyclophosphamide (FEC), followed by docetaxel (T) in the neoadjuvant setting.

PATIENTS AND METHODS

A total of 64 invasive breast cancer patients were recruited in the N001 Phase II, multicenter, open-label, single-arm study to receive four cycles of FEC (500, 100, 500 mg/m(2)) followed by four cycles of T (100 mg/m(2)) with concurrent CXB (200 mg b.i.d.) as neoadjuvant therapy (NAT). The combined chemotherapies were administered on day 1 of each cycle every 3 weeks. Primary endpoints were pathologic complete response (pCR) rate and objective response rate (ORR). Quasi-pCR (QpCR), pCR and near pCR (npCR) were discussed considering their similar survival outcomes. ORR included clinical complete response (cCR) and clinical partial response (cPR). Secondary endpoints included safety, breast conservation rate and disease-free survival.

RESULTS

Between February 2006 and January 2010, 57 of 64 evaluable patients with luminal A (n = 35, 61.4%), luminal B (n = 12, 21.1%), HER-2 positive (n = 8, 14%) and triple-negative (n = 2, 3.5%) breast cancer completed NAT and surgery. QpCR rate was observed in 18 (31.6%) patients. Exclusive of triple-negative subtype, pCR (p = 0.761) did not differ compared to other subtypes, while npCR (p = 0.043) exhibited a difference. Patients with HER-2 overexpression had a significantly higher QpCR than those of the disease attribute (10/20 vs 8/37, p = 0.029). After NAT, 43 (75.4%) and 13 (22.8%) patients achieved cCR and cPR, respectively. Patients responding to FEC were more likely to achieve a better ORR after subsequent T (p = 0.004). Over 80% of all patients received breast-conserving therapy (BCT) after receiving NAT, and 11 of 14 (78.6%) patients with T3 tumor at diagnosis became eligible for BCT after NAT. A total of 60 patients completed ≥ 6 cycles of NAT, followed by surgery; at a median follow-up of 50 months, 80% of the patients are disease-free. Neither drug-induced life-threatening toxicity nor cardiotoxicity was observed.

CONCLUSIONS

Neoadjuvant use of FEC-T with concurrent CXB is active and safe for treatment of operable invasive breast cancer. The ORR was higher, but QpCR was comparable to other studies. Most patients are still disease-free, and BCT became an option for the females. Further clinical and translational studies on the use of cyclooxygenase-2 inhibitors with neoadjuvant chemotherapy are warranted.

Anticancer effects of 4-vinyl-2,6-dimethoxyphenol (canolol) against SGC-7901 human gastric carcinoma cells

Gastric cancer remains the fourth most commonly diagnosed cancer and is the second leading cause of cancer-related mortality worldwide. The aim of this study was to investigate the effects of canolol on the proliferation and apoptosis of SGC-7901 human gastric cancer cells and its relevant molecular mechanisms. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to observe the effect of canolol on the proliferation of SGC-7901 human gastric adenocarcinoma cells. The results showed that SGC-7901 cells exhibited a marked dose-dependent reduction in the proliferation rate. The survival rate of the cells was 88.86±1.58% at 50 μmol/l, decreasing to 53.73±1.51% at 800 μmol/l (P<0.05). By contrast, canolol had no significant toxicity on the human gastric mucosal epithelial cell line GES-1. The vivid images of cell morphology using an inverted microscope provided confirmation of the MTT assay. Treatment of SGC-7901 cells with canolol resulted in apoptosis demonstrated by flow cytometry. Furthermore, canolol downregulated the mRNA levels of COX-2, but had no significant effect on the mRNA expession of the Bax and Bcl-2 genes. These findings suggest that canolol has potential to be developed as a new natural anti-gastric carcinoma agent.

Eicosanoids and adipokines in breast cancer: from molecular mechanisms to clinical considerations

Chronic inflammation is one of the foremost risk factors for different types of malignancies, including breast cancer. Additional risk factors of this pathology in postmenopausal women are weight gain, obesity, estrogen secretion, and an imbalance in the production of adipokines, such as leptin and adiponectin. Various signaling products of transcription factor, nuclear factor-kappaB, in particular inflammatory eicosanoids, reactive oxygen species (ROS), and cytokines, are thought to be involved in chronic inflammation-induced cancer. Together, these key components have an influence on inflammatory reactions in malignant tissue damage when their levels are deregulated endogenously. Prostaglandins (PGs) are well recognized in inflammation and cancer, and they are solely biosynthesized through cyclooxygenases (COXs) from arachidonic acid. Concurrently, ROS give rise to bioactive isoprostanes from arachidonic acid precursors that are also involved in acute and chronic inflammation, but their specific characteristics in breast cancer are less demonstrated. Higher aromatase activity, a cytochrome P-450 enzyme, is intimately connected to tumor growth in the breast through estrogen synthesis, and is interrelated to COXs that catalyze the formation of both inflammatory and anti-inflammatory PGs such as PGE(2), PGF(2α), PGD(2), and PGJ(2) synchronously under the influence of specific mediators and downstream enzymes. Some of the latter compounds upsurge the intracellular cyclic adenosine monophosphate concentration and appear to be associated with estrogen synthesis. This review discusses the role of COX- and ROS-catalyzed eicosanoids and adipokines in breast cancer, and therefore ranges from their molecular mechanisms to clinical aspects to understand the impact of inflammation.

Sphingomyelin synthase 2 over-expression induces expression of aortic inflammatory biomarkers and decreases circulating EPCs in ApoE KO mice

AIMS

This study sought to assess the effect of sphingomyelin synthase 2 (SMS2) over-expression on plaque component and endothelial dysfunction in atherosclerosis.

MAIN METHODS

We generated recombinant adenovirus vectors containing human SMS2 cDNA (AdV-SMS2) or control gene GFP cDNA (AdV-GFP). Both AdVs were injected (i.v.) into ApoE KO mice to establish SMS2 over-expressing and control mice models, respectively. The mice were fed a high fat diet for 30 days. We then examined their plasma lipid levels, expression levels of aortic inflammatory biomarkers critical for the plaque's stability, and numbers of peripheral endothelial progenitor cells (EPC).

KEY FINDINGS

Compared with the control mice, SMS2 over-expression had significantly (1) increased aortic matrix metalloproteinase-2 (MMP-2), monocyte chemoattractant protein-1 (MCP-1), tissue factor (TF) and cyclooxygenase-2 (COX-2) mRNA levels (1.9-fold, 2.2-fold, 2.6-fold and 3.2-fold, respectively, P<0.01) and protein levels (2.2-fold, 1.9-fold, 1.9-fold and 2.1-fold, respectively, P<0.01); (2) increased MMP-2, COX-2 in situ expression in aortic root (2.6-fold and 2.3-fold, respectively, P<0.01); (3) decreased aortic COX-1 mRNA levels (65%, P<0.01) and protein levels (64%, P<0.01); and (4) decreased CD34/KDR-positive cells (33%, P<0.01), circulating angiogenic cells (CACs) (50%, P<0.05), and colony forming units (CFUs) (40%, P<0.05) in circulation.

SIGNIFICANCE

SMS2 over-expression was probably associated with increased expression of aortic inflammatory biomarkers, as well as decreased numbers of CD34/KDR-positive cells, CACs and CFUs in circulation. Therefore, SMS2 over-expression might correlate with endothelial dysfunction and aggravate atherosclerotic plaque instability in ApoE KO mice.

Antiproliferative effects of selective cyclooxygenase-2 inhibitor modulated by nimotuzumab in estrogen-dependent breast cancer cells

Breast cancer is the most common malignancy in women, and many breast cancer patients fail conventional treatment strategies of chemotherapy, radiation, and antiestrogen therapy. Research into the molecular pathways and biomarkers involved in the development of breast cancer should yield information that will guide therapeutic decisions. Epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) are involved in the carcinogenesis of breast cancer and exist tight crosstalk with estrogen receptor (ER) pathway. Combination of EGFR and COX-2 inhibitors, therefore, could be an effective strategy for reducing cell growth in estrogen-dependent breast cancer. In order to verify the effects of EGFR and COX-2 inhibitors, breast cancer cells MCF-7 and SKBR-3 were characterized for receptors status and then treated with respective inhibitors (nimotuzumab and celecoxib) alone and in combination. Both cell lines were sensitive to celecoxib, but not to nimotuzumab. However, combination of two drugs demonstrated synergistic effects on cell killing. Moreover, association of two drugs resulted in SKBR-3 cells, a further G0/G1 phase arrest than one drug alone. Downregulation of p-EGFR, p-Akt, p-mTOR, and amplified in breast cancer 1 (AIB1) were observed in both cell lines, and upregulation of E-cadherin was only found in MCF-7, after treatment with single agent or in combination. These studies suggest that nimotuzumab and celecoxib exert synergistic antiproliferation effects in breast cancer, which partly correlates with ER status. Due to Akt/mTOR, EMT and AIB1 pathways participate in this process, therefore, E-cadherin and AIB1 may be considered as possible biomarkers to predict response in ER-positive breast cancer cells treated with EGFR and COX-2 inhibitors.

Targeting myeloid regulatory cells in cancer by chemotherapeutic agents

Recent findings in humans and numerous experimental models provide evidence of the important role of immune regulatory cells in cancer and various diseases. "Myeloid regulatory cells" (MRC) include myeloid-derived suppressor cells, regulatory dendritic cells, regulatory macrophages, and subsets of granulocytes that expand during pathologic conditions and that have the ability to suppress cellular immunity. A decrease in MRC population and/or activity has been shown to have positive immune-potentiating effects. Several clinical trials have thus been initiated with the goal of manipulating the expansion or activation of these cells and thereby improving patient immune responses. New data from our own and other laboratories recently revealed that ultralow noncytotoxic doses of certain chemotherapeutic drugs could up-regulate antitumor immunity by modulating the formation, differentiation, and/or function of MRC. This new phenomenon, termed "chemomodulation," allows for the regulation of the tumor microenvironment without the undesirable toxic effects associated with conventional chemotherapy. However, further studies are required before this new targeted therapy can find its way to patients with cancer.

Impairment of breast cancer cell invasion by COX-2-specific inhibitor NS398: roles of CXCR4 and of uPA system

Inhibition of cyclooxygenase-2 (COX-2) is known to impair cancer cell metastatic behaviour, but the mechanisms involved largely remain elusive. We aimed to analyse whether the antimetastatic effect of COX-2 inhibition in breast cancer cells could be explained by variations in the expression levels of chemokine receptor CXCR4, vascular endothelium growth factor (VEGF) and UPA/UPAR components of the urokinase plasminogen activator system (uPAR). Breast cancer cell line MDA-MB-231 was exposed to COX-2-specific inhibitor NS398. Experimental data were assessed using Matrigel invasion tests, qRT-PCR, ELISA, flow cytometry and MTT test. Exposure to NS398 had no major effect on cell viability, apoptosis or VEGF production. Cell invasion was significantly decreased with reductions ranging from of 3.6% with 10 μM NS398 to 81.04% with 100 μM NS398. CXCR4 membrane expression was significantly reduced by 18% (P < 0.05) when cells were treated with 100 μM of NS398 for 72 h. UPA mRNA levels were significantly reduced to 78 and 63% after treatment with 10 μM NS398 for 48 and 72 h, respectively (P < 0.05). UPAR mRNA levels also decreased with mild NS398 concentrations, reaching the lowest level of 56% with 50 μM of NS398 for 48 h (P < 0.05). With NS398 higher concentrations, UPAR and UPA expression levels increased. According to our results, impairment of expression of CXCR4, UPA and UPAR differentially contribute to the antimetastatic effect of COX-2 inhibitors depending on drug concentration.