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

Dual COX-2/5-LOX inhibitors from Zanthoxylum simulans inhibit gastric cancer cells by cross-mediating thyroid, estrogen, and oxytocin signaling pathways

Cyclooxygenase 2 (COX-2) and 5-lipoxygenase (5-LOX) are overexpressed in gastric cancer cells, the dual inhibitors of which exhibit potential against metastasis and invasion with fewer side effects. To discover inhibitors targeting COX-2 and 5-LOX, we conducted ultrafiltration and enrichment calculation to screen candidates in quaternary alkaloids (QAs) from Zanthoxylum simulans through LC and LC-Q-TOF. For intensive peaks, peaks 19 (berberine) and 21 (chelerythrine) were observed as the most potent dual candidates and showed selective affinity to 5-LOX over COX-2. Peak 19 showed an enrichment at 4.36 for COX-2 and 22.81 for 5-LOX, while peak 21 showed an enrichment at 7.81 for COX-2 and 24.49 for 5-LOX. Molecular docking results revealed chelerythrine as a better dual inhibitor, showing time- and dose-dependent anti-proliferation against AGS cells. Bio-informatics strategies, such as Gene Expression Omnibus (GEO), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG), suggested that hormone pathways in gastric cancer cells might be mediated by chelerythrine. Further reviews and summaries helped outline the mechanisms by which COX-2/5-LOX inhibitors might promote apoptosis in gastric cancer cells via estrogen, thyroid, and oxytocin signaling pathways. Chelerythrine was also added to gastric cancer cells to verify the regulation of these three signaling pathways. As a result, significant calling back of thyroid-stimulating hormone receptor (TSHR), thyroid hormone α3 (TRα3), and thyroid hormone receptor β1 (TRβ1) and suppressing estrogen receptor α36 (ER-α36)-Src could benefit the anti-proliferation of chelerythrine. However, it was disappointing that regulation of estrogen receptor α66 (ER-α66), estrogen receptor β (ER-β), and oxytocin receptor (OTR) contributed inversely negative effects on anti-gastric cancer cells. At present, the integrative study not only revealed chelerythrine as the most potent dual COX-2/5-LOX inhibitor from QAs but also generally highlighted that comprehensive regulation of the estrogen, thyroid, and oxytocin pathway should be noted once gastric cancer cells were treated with inflammatory inhibitors.

Hormonal Crosstalk Between Thyroid and Breast Cancer

Differentiated thyroid cancer and breast cancer account for a significant portion of endocrine-related malignancies and predominately affect women. As hormonally responsive tissues, the breast and thyroid share endocrine signaling. Breast cells are responsive to thyroid hormone signaling and are affected by altered thyroid hormone levels. Thyroid cells are responsive to sex hormones, particularly estrogen, and undergo protumorigenic processes upon estrogen stimulation. Thyroid and sex hormones also display significant transcriptional crosstalk that influences oncogenesis and treatment sensitivity. Obesity-related adipocyte alterations-adipocyte estrogen production, inflammation, feeding hormone dysregulation, and metabolic syndromes-promote hormonal alterations in breast and thyroid tissues. Environmental toxicants disrupt endocrine systems, including breast and thyroid homeostasis, and influence pathologic processes in both organs through hormone mimetic action. In this brief review, we discuss the hormonal connections between the breast and thyroid and perspectives on hormonal therapies for breast and thyroid cancer. Future research efforts should acknowledge and further explore the hormonal crosstalk of these tissues in an effort to further understand the prevalence of thyroid and breast cancer in women and to identify potential therapeutic options.

Effect of n-3 long-chain polyunsaturated fatty acid intake on the eicosanoid profile in individuals with obesity and overweight: a systematic review and meta-analysis of clinical trials

Dietary n-3 polyunsaturated fatty acids (PUFAs) present beneficial effects on counteracting inflammation status, displaying a critical anti-inflammatory role and maintaining physiological homeostasis in obesity. The primary objective of this systematic review was to evaluate the effect of n-3 PUFAs intake on the eicosanoid profile of people with obesity and overweight. The search strategy on Embase, Scopus, PubMed, Web of Science, Cochrane Library, Google Scholar and ProQuest was undertaken until November 2019 and updated January 2021. The effect size of n-3 PUFAs on prostaglandins was estimated by Glass's, type 1 in a random-effect model for the meta-analysis. Seven clinical trials met the eligible criteria and a total of 610 subjects were included in this systematic review, and four of seven studies were included in meta-analysis. The intake of n-3 PUFAs promoted an overall reduction in serum pro-inflammatory eicosanoids. Additionally, n-3 PUFAs intake significantly decreased the arachidonic acid COX-derived PG eicosanoid group levels (Glass's Δ -0⋅35; CI -0⋅62, -0⋅07, I ² 31⋅48). Subgroup analyses showed a higher effect on periods up to 8 weeks (Glass's Δ -0⋅51; CI -0⋅76, -0⋅27) and doses higher than 0⋅5 g of n-3 PUFAs (Glass's Δ -0⋅46; CI -0⋅72, -0⋅27). Dietary n-3 PUFAs intake contributes to reduce pro-inflammatory eicosanoids of people with obesity and overweight. Subgroup's analysis showed that n-3 PUFAs can reduce the overall arachidonic acid COX-derived PG when adequate dose and period are matched.

Chemopreventive and Anticancer Property of Selenoproteins in Obese Breast Cancer

Obesity is a significant risk factor for various cancers including breast cancer resulting in an increased risk of recurrence as well as morbidity and mortality. Extensive studies on various pathways have been successful in establishing a biological relationship between obesity and breast cancer. The molecular classification of breast cancer includes five groups each having different responses to treatment. Increased levels of inflammatory cytokines seen in obese conditions drive the pro-proliferative pathways, such as the influx of macrophages, angiogenesis, and antiapoptotic pathways. Increased peripheral aromatization of androgens by aromatase increases the circulating estrogen levels which are also responsible for the association of obesity with breast cancer. Also, increased oxidative stress due to chronic low-grade inflammation in obese women plays an important role in carcinogenesis. Despite the availability of safe and effective treatment options for breast cancer, obese women are at increased risk of adverse outcomes including treatment-related toxicities. In the recent decade, selenium compounds have gained substantial interest as chemopreventive and anticancer agents. The chemical derivatives of selenium include inorganic and organic compounds that exhibit pro-oxidant properties and alter cellular redox homeostasis. They target more than one metabolic pathway by thiol modifications, induction of reactive oxygen species, and chromatin modifications to exert their chemopreventive and anticancer activities. The primary functional effectors of selenium that play a significant role in human homeostasis are selenoproteins like glutathione peroxidase, thioredoxin reductase, iodothyronine deiodinases, and selenoprotein P. Selenoproteins play a significant role in adipose tissue physiology by modulating preadipocyte proliferation and adipogenic differentiation. They correlate negatively with body mass index resulting in increased oxidative stress that may lead to carcinogenesis in obese individuals. Methylseleninic acid effectively suppresses aromatase activation thus reducing the estrogen levels and acting as a breast cancer chemopreventive agent. Adipose-derived inflammatory mediators influence the selenium metabolites and affect the proliferation and metastatic properties of cancer cells. Recently selenium nanoparticles have shown potent anticancer activity which may lead to a major breakthrough in the management of cancers caused due to multiple pathways. In this review, we discuss the possible role of selenoproteins as chemopreventive and an anticancer agent in obese breast cancer.

Associations of Biomarkers of Inflammation and Breast Cancer in the Breast Adipose Tissue of Women with Combined Measures of Adiposity

BACKGROUND

Mechanisms underlying the obesity-breast cancer link involve inflammation but need to be elucidated. Determining obesity by combining body mass index (BMI) with the waist circumference (WC) may clarify the role of inflammatory and hormonally related markers in breast cancer. We examined the effect of combining adiposity indices (BMI/WC) with the gene expression of several biomarkers involved in breast cancer.

METHODS

Expression of cytochrome P450 family 19 subfamily A member 1 (CYP19A1), estrogen receptor-alpha (ER-α), allograft inflammatory factor 1 (AIF1), cyclooxygenase-2 (COX2), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and leptin (LEP) in 141 adipose breast tissues was quantified using qPCR method. BMI and WC were measured by a trained nurse and categorized using the median split, BMI^LOWC^LO, BMI^LOWC^HI, BMI^HIWC^LO, and BMI^HIWC^HI.

RESULTS

Gene expression of IL-6 (3-fold), TNF-α (2-fold), and LEP (2-fold) was higher in the breast adipose tissue of women with high WC regardless of BMI, that is, BMI^LOWC^HI and BMI^HIWC^HI women (all P < 0.01). Compared to BMI^LOWC^LO women, gene expression of CYP19A1, COX2, and AIF1 was increased by two-fold in breast adipose tissue of BMI^HIWC^HI women (P < 0.10). ER-α was not different across adiposity categories.

CONCLUSIONS

The expression of some biomarkers, particularly those related to inflammation, is elevated in breast adipose tissue of women with a high WC independent of BMI. Obesity monitoring should also include women with normal or low BMI, but with central adiposity.

Potential Benefit of Intra-operative Administration of Ketorolac on Breast Cancer Recurrence According to the Patient's Body Mass Index

Background

Nonsteroidal anti-inflammatory drugs (NSAIDs) are currently used in some countries as analgesics in primary cancer surgery. Retrospective studies suggest that NSAIDs could reduce breast cancer recurrences. Because NSAIDs also act on biological mechanisms present in patients with increased adiposity, we aimed at assessing whether the intra-operative administration of ketorolac or diclofenac would be associated with a reduction of recurrence in patients with elevated body mass index (BMI).

Methods

We considered two institutional retrospective series of 827 and 1007 patients evaluating the administration of ketorolac (n = 529 with, n = 298 without) or diclofenac (n = 787 with, n = 220 without). The BMI subgroups were defined as less than 25 kg/m2 (lean) and 25 or more kg/m2 (overweight and obese). Cumulative incidence estimation of distant metastases as well as Fine-Gray and Dixon-Simon models was used. These analyses were adjusted for clinico-pathological variables. All statistical tests were two-sided.

Results

The administration of ketorolac was statistically significantly associated with decreased incidence of distant recurrences (adjusted hazard ratio [aHR]= 0.59, 95% confidence interval [CI] = 0.37 to 0.96, P = .03). In particular, the association was evident in the high-body mass index (BMI) group of patients (aHR = 0.55, 95% CI = 0.31 to 0.96, P = .04). The administration of diclofenac was not statistically significantly associated with decreased incidence of distant recurrences, either in the global population or in the BMI subgroups.

Conclusions

These results show that the intra-operative administration of ketorolac, but not diclofenac, is statistically significantly associated with a reduction of distant recurrences in patients with increased BMI. Altogether, this study points to a potentially important repositioning of ketorolac in the intra-operative treatment of patients with elevated BMI that, if prospectively validated, might be as impactful as and cheaper than adjuvant systemic anticancer therapies.

The Dualistic Effect of COX-2-Mediated Signaling in Obesity and Insulin Resistance

Obesity and insulin resistance are two major risk factors for the development of metabolic syndrome, type 2 diabetes and associated cardiovascular diseases (CVDs). Cyclooxygenase (COX), a rate-limiting enzyme responsible for the biosynthesis of prostaglandins (PGs), exists in two isoforms: COX-1, the constitutive form, and COX-2, mainly the inducible form. COX-2 is the key enzyme in eicosanoid metabolism that converts eicosanoids into a number of PGs, including PGD₂, PGE₂, PGF_2α, and prostacyclin (PGI₂), all of which exert diverse hormone-like effects via autocrine or paracrine mechanisms. The COX-2 gene and immunoreactive proteins have been documented to be highly expressed and elevated in adipose tissue (AT) under morbid obesity conditions. On the other hand, the environmental stress-induced expression and constitutive over-expression of COX-2 have been reported to play distinctive roles under different pathological and physiological conditions; i.e., over-expression of the COX-2 gene in white AT (WAT) has been shown to induce de novo brown AT (BAT) recruitment in WAT and then facilitate systemic energy expenditure to protect mice against high-fat diet-induced obesity. Hepatic COX-2 expression was found to protect against diet-induced steatosis, obesity, and insulin resistance. However, COX-2 activation in the epidydimal AT is strongly correlated with the development of AT inflammation, insulin resistance, and fatty liver in high-fat-diet-induced obese rats. This review will provide updated information regarding the role of COX-2-derived signals in the regulation of energy metabolism and the pathogenesis of obesity and MS.

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.

PTGS2 polymorphism rs689466 favors breast cancer recurrence in obese patients

Breast cancer is the leading cancer among women, and its increasing incidence is a challenge worldwide. Estrogen exposure is the main risk factor, but obesity among postmenopausal women has been shown to favor disease onset and progression. The link between obesity and mammary carcinogenesis involves elevated estrogen production and proinflammatory stimuli within the adipose tissue, with activation of the cyclooxygenase-2 pathway. Here, we evaluate the impact of the four most common cyclooxygenase-2 gene polymorphisms (rs689465, rs689466, rs20417 and rs20417), in combination with obesity, on the risk of breast cancer progression in a cohort of Brazilian breast cancer patients (N = 1038). Disease-free survival was evaluated using Kaplan-Meier curves, with multivariate Cox proportional hazards regression models for calculation of adjusted hazard ratios (HR_adj). Obesity did not affect disease progression, whereas rs689466 variant genotypes increased the recurrence risk among obese patients (HR_adj = 2.5; 95% CI = 1.4-4.3), either for luminal (HR_adj = 2.2; 95% CI = 1.1-4.2) or HER2-like and triple-negative tumors (HR_adj = 3.2; 95% CI = 1.2-8.5). Likewise, the haplotype *4, which contains variant rs689466, was associated with shorter disease-free survival among obese patients (HR_adj = 3.3; 95% CI = 1.8-6.0), either in luminal (HR_adj = 3.5; 95% CI = 1.6-7.3) or HER2-like and triple-negative (HR_adj = 3.1; 95% CI = 1.1-8.9) tumors. Such deleterious impact of variant rs689466 on disease-free survival of obese breast cancer patients was restricted to postmenopausal women. In conclusion, cyclooxygenase-2 genotyping may add to the prognostic evaluation of obese breast cancer patients.

Effects of Obesity on the Regulation of Macrophage Population in the Prostate Tumor Microenvironment

Obesity is associated with a greater risk of prostate cancer mortality. However, the mechanisms connecting obesity to the progression of prostate cancer remain unknown. This study determined the impact of obesity on macrophage recruitment and tumor-associated macrophage (TAM) polarization in the prostate tumor microenvironment, since a high concentration of TAMs in tumors has been linked to progression in prostate cancer. We utilized an in vitro model in which pre-adipocytes, prostate cancer cells, and macrophages were exposed to sera from obese or nonobese men, or conditioned media generated under obese or nonobese conditions. Matrigel invasion chambers were used to assess macrophage recruitment in vitro, and immunohistochemical analysis evaluated recruitment in a PTEN knockout mouse model. qPCR was used to measure mRNA levels of CCL2, COX-2, IL-10, TGF-beta, VEGF-A, arginase-1, and MMP-9. PGE2 production was measured by ELISA. Obesity increased macrophage and TAM recruitment, and increased mRNA levels of TAM markers in macrophages. Similarly, obese conditions increased CCL2 and COX-2 expression, as well as PGE2 levels in prostate cancer cells. COX-2 inhibition resulted in lower expression of obesity-induced TAM markers. Our data suggest that obesity promotes macrophage infiltration into the prostate tumor microenvironment, and induces TAM polarization through the COX-2/PGE2 pathway.

Novel augmentation by bufalin of protein kinase C-induced cyclooxygenase-2 and IL-8 production in human breast cancer cells

Cyclooxygenase-2 (COX-2) and IL-8 are two inflammatory mediators induced by protein kinase C (PKC) via various stimuli. Both contribute significantly to cancer progression. Bufalin, a major active component of the traditional Chinese medicine Chan Su, is known to induce apoptosis in various cancer cells. This study clarifies the role and mechanism of bufalin action during PKC regulation of COX-2/IL-8 expression and investigates the associated impact on breast cancer. Using MB-231 breast cancer cells, bufalin augments PKC induction of COX-2/IL-8 at both the protein and mRNA levels, and the production of prostaglandin E2 (PGE2) and IL-8. The MAPK and NF-κB pathways are involved in both the PKC-mediated and bufalin-promoted PKC regulation of COX-2/IL-8 production. Bufalin increases PKC-induced MAPKs phosphorylation and NF-κB nuclear translocation. PGE2 stimulates the proliferation/migration of breast cancer cells. Furthermore, PKC-induced matrix metalloproteinase 3 expression is enhanced by bufalin. Bufalin significantly enhances breast cancer xenograft growth, which is accompanied by an elevation in COX-2/IL-8 expression. In conclusion, bufalin seems to promote the inflammatory response in vitro and in vivo, and this occurs, at least in part, by targeting the MAPK and NF-κB pathways, which then enhances the growth of breast cancer cells.

Activated Caspase 3 Expression in Remnant Disease After Neoadjuvant Chemotherapy May Predict Outcomes of Breast Cancer Patients

BACKGROUND

A number of studies have indicated that patients obtaining a pathological complete response (pCR) from neoadjuvant chemotherapy (NAC) have a good prognosis; however, prognostic factors for non-pCR patients are not yet well-established. By examining remnant cancer in non-pCR patients, the expression of cleaved Caspase 3 (Casp3), an activated apoptotic marker, was immunohistochemically investigated to determine whether this protein has the potential to serve as a novel marker for predicting patient outcomes.

METHODS

We investigated 218 patients with invasive breast cancer who received NAC and underwent surgery during the 2006 through 2008 period at our institution. Following surgery, standard adjuvant endocrine therapy was administered if a tumor was hormone receptor-positive. Casp3 was evaluated in remnant cancer based on the number of positive cells in five high-power fields.

RESULTS

pCR was obtained in 49 patients, and 50 of the 169 non-pCR patients developed recurrences during the median 82-month observation period. We found large tumor size, lymph node involvement, lymph vessel invasion, estrogen receptor-negative, progesterone receptor-negative, high Ki67 and high Casp3 expression to be factors related to tumor recurrence. A logistic regression model revealed that lymph node involvement, as well as high Ki67 and Casp3, to be factors independently predicting recurrence, while lymph vessel invasion and high Ki67 expression were found to be related to breast cancer mortality.

CONCLUSIONS

Patients with remnant cancer showing high Casp3 expression had poor outcomes. Our results showed that Casp3 is a potential prognostic marker for non-pCR patients.