CD47 blockade enhances the efficacy of intratumoral STING-targeting therapy by activating phagocytes

Activation of STING signaling plays an important role in anti-tumor immunity, and we previously reported the anti-tumor effects of STING through accumulation of M1-like macrophages in tumor tissue treated with a STING agonist. However, myeloid cells express SIRPα, an inhibitory receptor for phagocytosis, and its receptor, CD47, is overexpressed in various cancer types. Based on our findings that breast cancer patients with highly expressed CD47 have poor survival, we evaluated the therapeutic efficacy and underlying mechanisms of combination therapy with the STING ligand cGAMP and an antagonistic anti-CD47 mAb using E0771 mouse breast cancer cells. Anti-CD47 mAb monotherapy did not suppress tumor growth in our setting, whereas cGAMP and anti-CD47 mAb combination therapy inhibited tumor growth. The combination therapy enhanced phagocytosis of tumor cells and induced systemic anti-tumor immune responses, which rely on STING and type I IFN signaling. Taken together, our findings indicate that coadministration of cGAMP and an antagonistic anti-CD47 mAb may be promising for effective cancer immunotherapy.

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Investigating New Therapeutic Strategies Targeting Hyperinsulinemia's Mitogenic Effects in a Female Mouse Breast Cancer Model

Endocrinology ◽

10.1210/en.2012-2263 ◽

2013 ◽

Vol 154 (5) ◽

pp. 1701-1710 ◽

Cited By ~ 21

Author(s):

Ran Rostoker ◽

Keren Bitton-Worms ◽

Avishay Caspi ◽

Zila Shen-Orr ◽

Derek LeRoith

Keyword(s):

Breast Cancer ◽

Tumor Growth ◽

Breast Tumor ◽

Experimental Studies ◽

Tumor Development ◽

Treated Group ◽

Tumor Growth Rate ◽

Breast Cancer Patients ◽

Mitogenic Effect

Abstract Epidemiological and experimental studies have identified hyperinsulinemia as an important risk factor for breast cancer induction and for the poor prognosis in breast cancer patients with obesity and type 2 diabetes. Recently it was demonstrated that both the insulin receptor (IR) and the IGF-IR mediate hyperinsulinemia's mitogenic effect in several breast cancer models. Although IGF-IR has been intensively investigated, and anti-IGF-IR therapies are now in advanced clinical trials, the role of the IR in mediating hyperinsulinemia's mitogenic effect remains to be clarified. Here we aimed to explore the potential of IR inhibition compared to dual IR/IGF-IR blockade on breast tumor growth. To initiate breast tumors, we inoculated the mammary carcinoma Mvt-1 cell line into the inguinal mammary fat pad of the hyperinsulinemic MKR female mice, and to study the role of IR, we treated the mice bearing tumors with the recently reported high-affinity IR antagonist-S961, in addition to the well-documented IGF-IR inhibitor picropodophyllin (PPP). Although reducing IR activation, with resultant severe hyperglycemia and hyperinsulinemia, S961-treated mice had significantly larger tumors compared to the vehicle-treated group. This effect maybe secondary to the severe hyperinsulinemia mediated via the IGF-1 receptor. In contrast, PPP by partially inhibiting both IR and IGF-IR activity reduced tumor growth rate with only mild metabolic consequences. We conclude that targeting (even partially) both IR and IGF-IRs impairs hyperinsulinemia's effects in breast tumor development while simultaneously sparing the metabolic abnormalities observed when targeting IR alone with virtual complete inhibition.

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Efficacy and tolerability of Everolimus-Exemestane combination therapy in metastatic breast cancer patients: experience in Real Life

Annals of Oncology ◽

10.1093/annonc/mdv336.72 ◽

2015 ◽

Vol 26 ◽

pp. vi25

Author(s):

V. Cocciolone ◽

K. Cannita ◽

A. Tessitore ◽

L. Rinaldi ◽

A. Irelli ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Combination Therapy ◽

Cancer Patients ◽

Real Life ◽

Metastatic Breast ◽

Breast Cancer Patients ◽

Patients Experience

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cPLA2 Blockade Attenuates S100A7-Mediated Breast Tumorigenicity by Inhibiting the Immunosuppressive Tumor Microenvironment

10.21203/rs.3.rs-829313/v1 ◽

2021 ◽

Author(s):

SANJAY MISHRA ◽

Manish Charan ◽

Rajni Kant Shukla ◽

Pranay Agarwal ◽

Swati Misri ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Tumor Microenvironment ◽

Tumor Growth ◽

Breast Cancer Cells ◽

Metastatic Breast ◽

Breast Cancer Patients ◽

Immunosuppressive Tumor Microenvironment ◽

Tumor Growth And Metastasis ◽

Breast Cancer Growth

Abstract Background: Metastasis is the major cause of mortality in breast cancer; however, the molecular mechanisms remain elusive. In our previous study, we demonstrated that S100A7/RAGE mediates breast cancer growth and metastasis by recruitment of tumor-associated macrophages. However, the downstream S100A7-mediated inflammatory oncogenic signaling cascade that enhances breast tumor growth and metastasis by generating the immunosuppressive tumor microenvironment (iTME) has not been studied. In this present study, we aimed to investigate the S100A7 and cPLA2 cross-talk in enhancing tumor growth and metastasis through enhancing the iTME.Methods: Human breast cancer tissue and plasma samples were used to analyze the expression of S100A7, cPLA2, and PGE2 titer. S100A7-overexpressing or downregulated human metastatic breast cancer cells were used to evaluate the S100A7-mediated downstream signaling mechanisms. Bi-transgenic mS100a7a15 overexpression, TNBC C3(1)/Tag transgenic, and humanized patient-derived xenograft mouse models and cPLA2 inhibitor (AACOCF3) were used to investigate the role of S100A7/cPLA2/PGE2 signaling in tumor growth and metastasis. Additionally, CODEX, a highly advanced multiplexed imaging was employed to delineate the effect of S100A7/cPLA2 inhibition on the recruitment of various immune cells.Results: S100A7 and cPLA2 are highly expressed and positively correlated in malignant breast cancer patients. S100A7/RAGE upregulates cPLA2/PGE2 axis in aggressive breast cancer cells. Furthermore, S100A7 is positively correlated with PGE2 in breast cancer patients. Moreover, cPLA2 pharmacological inhibition suppressed S100A7-mediated tumor growth and metastasis in multiple pre-clinical models. Mechanistically, S100A7-mediated activation of cPLA2 enhances the recruitment of immunosuppressive myeloid cells by increasing PGE2 to fuel breast cancer growth and its secondary spread. We revealed that cPLA2 inhibitor mitigates S100A7-mediated breast tumorigenicity by suppressing the iTME. Furthermore, CODEX imaging data showed that cPLA2 inhibition increased the infiltration of CD4+/CD8+ T cells in the TME. Analysis of metastatic breast cancer samples revealed a positive correlation between S100A7/cPLA2 with CD163+ tumor-associated M2-macrophages.Conclusions: Our study shows that cross-talk between S100A7 and cPLA2 plays an important role in enhancing breast tumor growth and metastasis by generating an immunosuppressive tumor microenvironment and reducing infiltration of T cells. Furthermore, S100A7 could be used as a novel non-invasive prognostic marker and cPLA2 inhibitors as promising drugs against S100A7-overexpressing metastatic breast cancer.

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Clinical Impact of Sphingosine-1-Phosphate in Breast Cancer

Mediators of Inflammation ◽

10.1155/2017/2076239 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 15

Author(s):

Junko Tsuchida ◽

Masayuki Nagahashi ◽

Kazuaki Takabe ◽

Toshifumi Wakai

Keyword(s):

Breast Cancer ◽

Cancer Patients ◽

Cancer Metastasis ◽

Clinical Importance ◽

Breast Cancer Metastasis ◽

Lipid Mediator ◽

Breast Cancer Patients ◽

Cellular Functions ◽

Sphingosine 1 Phosphate ◽

Underlying Mechanisms

Breast cancer metastasizes to lymph nodes or other organs, which determine the prognosis of patients. It is difficult to cure the breast cancer patients with distant metastasis due to resistance to drug therapies. Elucidating the underlying mechanisms of breast cancer metastasis and drug resistance is expected to provide new therapeutic targets. Sphingosine-1-phosphate (S1P) is a pleiotropic, bioactive lipid mediator that regulates many cellular functions, including proliferation, migration, survival, angiogenesis/lymphangiogenesis, and immune responses. S1P is formed in cells by sphingosine kinases and released from them, which acts in an autocrine, paracrine, and/or endocrine manner. S1P in extracellular space, such as interstitial fluid, interacts with components in the tumor microenvironment, which may be important for metastasis. Importantly, recent translational research has demonstrated an association between S1P levels in breast cancer patients and clinical outcomes, highlighting the clinical importance of S1P in breast cancer. We suggest that S1P is one of the key molecules to overcome the resistance to the drug therapies, such as hormonal therapy, anti-HER2 therapy, or chemotherapy, all of which are crucial aspects of a breast cancer treatment.

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