Single-cell transcriptome analysis reveals T-cell exhaustion in denosumab-treated giant cell tumor of bone

Abstract

Denosumab (DMAB), a human monoclonal antibody against the receptor activator of the nuclear factor-kappa B ligand, is used for the treatment for unresectable giant cell tumor of bone (GCTB). However, little is known about the molecular and functional characteristics of GCTB-infiltrating lymphocytes after DMAB treatment. Here, we performed single-cell RNA sequencing and immunostaining assays to delineate the immune landscape of GCTB in the presence and absence of DMAB. We found that exhausted CD8+ T cells were preferentially enriched in DMAB-treated GCTB. A distinct M2-skewed type of tumor-associated macrophages (TAMs) comprises the majority of GCTB TAMs. We identified cytokines, including interleukin-10, and inhibitory receptors of M2 TAMs as important mediators of CD8+ T cell exhaustion. We further revealed that DMAB treatment notably increased the expression levels of periostin (POSTN) in GCTB cells. Furthermore, POSTN expression was transcriptionally regulated by c-FOS signaling and correlated with GCTB recurrence in patients after DMAB treatment. Collectively, our findings reveal that CD8+ T-cells undergo unappreciated exhaustion during DMAB therapy and that GCTB cell-derived POSTN educates TAMs and establishes a microenvironmental niche that facilitates GCTB recurrence.

Single‐cell RNA sequencing reveals distinct immune cell subsets in phalangeal and soft‐tissue recurrence of giant cell tumor of bone

“…Our previous research provided a comprehensive catalog of immune cells present in conventional GCTB (Figure 7g) [19]. However, there is a scarcity of published information regarding GCTB in rare sites, particularly in the distal phalanx.…”

“…This investigation was sanctioned by the Medical Ethics Committee of the First Affiliated Hospital of Sun Yat‐Sen University and all subjects provided informed consent prior to surgery. For scRNA‐seq, three patients with GCTB occurring in the femur [19], phalanx, and recurring in the soft tissue were diagnosed pathologically and underwent surgical excision at the First Affiliated Hospital of Sun Yat‐Sen University. Formalin‐fixed, paraffin‐embedded tissue blocks were obtained from GCTB cases occurring, respectively, in the long bone (conventional GCTB), phalanx, and recurring in the soft tissue, for use in immunohistochemistry (IHC) staining assays.…”

“…Our prior investigation, utilizing scRNA‐seq, unveiled the existence of exhausted CD8 + T cells in denosumab‐treated giant cell tumor of the bone (GCTB). Additionally, our data indicated that the GCTB cell‐derived protein PERIOSIN is associated with the M2 tumor‐associated macrophage (TAM) phenotype and GCTB recurrence [19]. Despite these compelling results, the TME of rare GCTB sites remains poorly understood.…”

Single-cell analysis reveals cellular reprogramming in advanced colon cancer following FOLFOX-bevacizumab treatment

“…The preparation of single-cell suspensions and scRNA-seq was conducted according to previously published methods (12,13). In brief, fresh tumor biopsy tissue was dissociated, erythrocytes were lysed, and cell viability was tested.…”

“…We identified cancer cells using epithelial cell marker genes (EPCAM, KRT19, KRT18) and inferred copy number variations (CNVs) profiles as previously described in our studies (12,13). We performed InferCNV within each sample using immune cells, including T cells, B cells, and myeloid cells, as the reference group and cancer cells as the observation group.…”