Anti-GD2 antibody dinutuximab inhibits triple-negative breast tumor growth by targeting GD2⁺ breast cancer stem-like cells

Abstract

BackgroundTriple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype with no effective standard therapy. Breast cancer stem-like cells (BCSCs) in primary TNBCs are reported to be responsible for metastatic spread of the disease and resistance to chemotherapy, but no available therapeutic tools target BCSCs. We previously reported that the ganglioside GD2 is highly expressed on BCSCs and that inhibition of its expression hampers TNBC growth. We therefore hypothesized that the anti-GD2 antibody dinutuximab (ch14.18) targets GD2+ BCSCs and inhibits TNBC growth.MethodTo test our hypothesis, we first determined GD2 expression via immunohistochemistry in frozen primary tumor samples from patients with TNBC (n=89). Then, we examined the effects of dinutuximab on TNBC cell adhesion, migration, and mammosphere formation in vitro and on tumor growth in vivo using TNBC cell-line and patient-derived xenograft (PDX) models.ResultsWe found that GD2 was expressed in around 60% of primary TNBC tumors at variable levels and was associated with worse overall survival of patients with TNBC (p=0.002). GD2 was found to be expressed in tumors and stroma, but normal ducts and lobules in adjacent tissues have shown low or no GD2 staining, indicating that GD2 is potentially a novel biomarker for tumor and its microenvironment. Treatment with dinutuximab significantly decreased adhesion and migration of MDA-MB-231 and SUM159 TNBC cells. Moreover, dinutuximab treatment inhibited mTOR signaling, which has been shown to be regulated by GD2 in BCSCs. Dinutuximab also reduced tumor growth in nude mice bearing TNBC cell-line xenografts. Finally, dinutuximab in combination with activated natural killer cells inhibited tumor growth in a TNBC PDX model and improved overall survival of tumor-bearing mice.ConclusionsDinutuximab successfully eliminated GD2+ cells and reduced tumor growth in both in vivo models. Our data provide proof-of-concept for the criticality of GD2 in BCSCs and demonstrate the potential of dinutuximab as a novel therapeutic approach for TNBC.

Ganglioside GD2 Enhances the Malignant Phenotypes of Melanoma Cells by Cooperating with Integrins

“…They have also been reported to be expressed in osteosarcomas [ 23 , 24 , 25 ], breast cancers [ 26 ], and T-cell leukemias [ 27 , 28 , 29 , 30 ]. Attention to GD2 is especially increasing, i.e., as cancer-associated glycolipids in various cancers, and a marker to indicate higher malignant properties of cancers [ 22 ], and/or cancer stem cells [ 17 ] and triple-negative breast cancers [ 18 ]. GD2 has been used as a target of antibody therapy [ 31 , 32 ] towards neuroblastomas [ 33 ], gliomas [ 34 ], and breast cancers [ 26 ], and also of CAR-T therapy of various cancers [ 19 , 20 ].…”

“…Among the cancer-associated glycolipids, GD2 is specifically important because of its key roles in the metastasis of melanomas [ 16 ], as a marker of cancer stem cells for breast cancers [ 17 ] and triple-negative breast cancers [ 18 ], and as targets of novel immune therapy for neuroectoderm-derived cancers [ 19 ] and other cancers, too [ 20 ].…”

O-Acetyl-GD2 as a Therapeutic Target for Breast Cancer Stem Cells

“…These results suggest that anti-OAcGD2 might be an ideal immunotherapeutic agent for BCSCs-targeted therapy of breast cancer. GD2 has been reported as a specific cell surface marker of BCSCs in triple-negative breast cancer (TNBC) (12,(28)(29)(30). In these studies, an anti-GD2 antibody 14G2a was used to identify the GD2 + cells.…”

The Role of Sphingolipids in Cancer Immunotherapy

“…Ch14.18 mAb (dinutuximab) was approved by Food & Drug Administration (FDA) and European Medicines Agency (EMA) for high-risk neuroblastoma patients in combination with other therapies, and increases five-year survival by 20% [ 104 ]. The same antibody has been demonstrated to be efficacious against triple negative breast cancer [ 105 ]. Ch14.18 Ab is a human-murine chimeric antibody obtained by joining the variable region of murine IgG3 anti-GD2 mAb 14.18 and the constant region of human IgG1 [ 92 , 105 ] ( Figure 3 A).…”

“…The same antibody has been demonstrated to be efficacious against triple negative breast cancer [ 105 ]. Ch14.18 Ab is a human-murine chimeric antibody obtained by joining the variable region of murine IgG3 anti-GD2 mAb 14.18 and the constant region of human IgG1 [ 92 , 105 ] ( Figure 3 A). Ch14.18 was then produced in Chinese hamster ovary (CHO) cells instead of the murine myeloma cell line, SP2/0, giving the mAb known as dinutuximab-beta with similar GD2 binding, toxicity, and pharmacokinetics [ 92 ].…”