1
|
Ding J, Jin W, Chen C, Shao Z, Wu J. Tumor associated macrophage × cancer cell hybrids may acquire cancer stem cell properties in breast cancer. PLoS One 2012; 7:e41942. [PMID: 22848668 PMCID: PMC3405038 DOI: 10.1371/journal.pone.0041942] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 06/28/2012] [Indexed: 02/07/2023] Open
Abstract
Breast cancer is one of the most frequently diagnosed cancers among women, and metastasis makes it lethal. Tumor-associated macrophages (TAMs) that acquire an alternatively activated macrophage (M2) phenotype may promote metastasis. However, the underlying mechanisms are still elusive. Here, we examined how TAMs interact with breast cancer cells to promote metastasis. Immunohistochemistry was used to examine the expression of the M2-specific antigen CD163 in paraffin-embedded mammary carcinoma blocks to explore fusion events in breast cancer patients. U937 cells were used as a substitute for human monocytes, and these cells differentiated into M2 macrophages following phorbol 12-myristate 13-acetate (PMA) and M-CSF stimulation. M2 macrophages and the breast cancer cell lines MCF-7 and MDA-MB-231 fused in the presence of 50% polyethylene glycol. Hybrids were isolated by fluorescence-activated cell sorting, and the relevant cell biological properties were compared with their parental counterparts. Breast cancer stem cell (BCSC)-related markers were quantified by immunofluorescence staining, RT-PCR, quantitative RT-PCR and/or western blotting. The tumor-initiating and metastatic capacities of the hybrids and their parental counterparts were assessed in NOD/SCID mice. We found that the CD163 expression rate in breast cancer tissues varied significantly and correlated with estrogen receptor status (p<0.05). The fusion efficiency of either breast cancer cell line with M2 macrophages ranged from 1.81 to 6.47% in the presence of PEG, and no significant difference was observed between the breast cancer cell lines used (p>0.05). Characterization of the fusion hybrids revealed a more aggressive phenotype, including increased migration, invasion and tumorigenicity, but reduced proliferative ability, compared with the parental lines. The hybrids also gained a CD44(+)CD24(-/low) phenotype and over-expressed epithelial-mesenchymal transition-associated genes. These results indicate that TAMs may promote breast cancer metastasis through cell fusion, and the hybrids may gain a BCSC phenotype.
Collapse
Affiliation(s)
- Jingxian Ding
- Department of Breast Surgery, Breast Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
- Fudan University Cancer Institute Research Center, Shanghai, China
| | - Wei Jin
- Department of Breast Surgery, Breast Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Canming Chen
- Department of Breast Surgery, Breast Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhiming Shao
- Department of Breast Surgery, Breast Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jiong Wu
- Department of Breast Surgery, Breast Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
- * E-mail:
| |
Collapse
|
2
|
Espert L, Denizot M, Grimaldi M, Robert-Hebmann V, Gay B, Varbanov M, Codogno P, Biard-Piechaczyk M. Autophagy is involved in T cell death after binding of HIV-1 envelope proteins to CXCR4. J Clin Invest 2006; 116:2161-72. [PMID: 16886061 PMCID: PMC1523410 DOI: 10.1172/jci26185] [Citation(s) in RCA: 350] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Accepted: 05/09/2006] [Indexed: 01/16/2023] Open
Abstract
HIV-1 envelope glycoproteins (Env), expressed at the cell surface, induce apoptosis of uninfected CD4+ T cells, contributing to the development of AIDS. Here we demonstrate that, independently of HIV replication, transfected or HIV-infected cells that express Env induced autophagy and accumulation of Beclin 1 in uninfected CD4+ T lymphocytes via CXCR4. The same phenomena occurred in a T cell line and in transfected HEK.293 cells that expressed both wild-type CXCR4 and a truncated form of CD4 that is unable to bind the lymphocyte-specific protein kinase Lck. Env-mediated autophagy is required to trigger CD4+ T cell apoptosis since blockade of autophagy at different steps, by either drugs (3-methyladenine and bafilomycin A1) or siRNAs specific for Beclin 1/Atg6 and Atg7 genes, totally inhibited the apoptotic process. Furthermore, CD4+ T cells still underwent Env-mediated cell death with autophagic features when apoptosis was inhibited. These results suggest that HIV-infected cells can induce autophagy in bystander CD4+ T lymphocytes through contact of Env with CXCR4, leading to apoptotic cell death, a mechanism most likely contributing to immunodeficiency.
Collapse
Affiliation(s)
- Lucile Espert
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| | - Mélanie Denizot
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| | - Marina Grimaldi
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| | - Véronique Robert-Hebmann
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| | - Bernard Gay
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| | - Mihayl Varbanov
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| | - Patrice Codogno
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| | - Martine Biard-Piechaczyk
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, Montpellier, France.
INSERM U504, Villejuif, France
| |
Collapse
|