Inflammatory Breast Cancer: The Secretome of HCMV+ Tumor-Associated Macrophages Enhances Proliferation, Invasion, Colony Formation, and Expression of Cancer Stem Cell Markers

Hossam Taha Mohamed; Aya Ali El-Sharkawy; Mohamed El-Shinawi; Robert J Schneider; Mona Mostafa Mohamed

doi:10.3389/fonc.2022.899622

Inflammatory Breast Cancer: The Secretome of HCMV⁺ Tumor-Associated Macrophages Enhances Proliferation, Invasion, Colony Formation, and Expression of Cancer Stem Cell Markers

Front Oncol. 2022 Jun 30:12:899622. doi: 10.3389/fonc.2022.899622. eCollection 2022.

Authors

Hossam Taha Mohamed^{1

2}, Aya Ali El-Sharkawy¹, Mohamed El-Shinawi^{3

4}, Robert J Schneider⁵, Mona Mostafa Mohamed^{1

6}

Affiliations

¹ Zoology Department, Faculty of Science, Cairo University, Giza, Egypt.
² Faculty of Biotechnology, October University for Modern Sciences and Arts, Giza, Egypt.
³ Department of General Surgery, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
⁴ Galala University, Suez, Egypt.
⁵ Department of Microbiology, School of Medicine, New York University, New York, NY, United States.
⁶ Sector of International Cooperation, Galala University, Suez, Egypt.

Abstract

Inflammatory breast cancer (IBC) is a highly aggressive phenotype of breast cancer that is characterized by a high incidence early metastasis. We previously reported a significant association of human cytomegalovirus (HCMV) DNA in the carcinoma tissues of IBC patients but not in the adjacent normal tissues. HCMV-infected macrophages serve as "mobile vectors" for spreading and disseminating virus to different organs, and IBC cancer tissues are highly infiltrated by tumor-associated macrophages (TAMs) that enhance IBC progression and promote breast cancer stem cell (BCSC)-like properties. Therefore, there is a need to understand the role of HCMV-infected TAMs in IBC progression. The present study aimed to test the effect of the secretome (cytokines and secreted factors) of TAMs derived from HCMV⁺ monocytes isolated from IBC specimens on the proliferation, invasion, and BCSC abundance when tested on the IBC cell line SUM149. HCMV⁺ monocytes were isolated from IBC patients during modified radical mastectomy surgery and tested in vitro for polarization into TAMs using the secretome of SUM149 cells. MTT, clonogenic, invasion, real-time PCR arrays, PathScan Intracellular Signaling array, and cytokine arrays were used to characterize the secretome of HCMV⁺ TAMs for their effect on the progression of SUM149 cells. The results showed that the secretome of HCMV⁺ TAMs expressed high levels of IL-6, IL-8, and MCP-1 cytokines compared to HCMV^- TAMs. In addition, the secretome of HCMV⁺ TAMs induced the proliferation, invasion, colony formation, and expression of BCSC-related genes in SUM149 cells compared to mock untreated cells. In addition, the secretome of HCMV⁺ TAMs activated the phosphorylation of intracellular signaling molecules p-STAT3, p-AMPKα, p-PRAS40, and p-SAPK/JNK in SUM149 cells. In conclusion, this study shows that the secretome of HCMV⁺ TAMs enhances the proliferation, invasion, colony formation, and BCSC properties by activating the phosphorylation of p-STAT3, p-AMPKα, p-PRAS40, and p-SAPK/JNK intracellular signaling molecules in IBC cells.

Keywords: breast cancer stem cell; human cytomegalovirus; inflammatory breast cancer; secretome; tumor-associated macrophages.