Research progress of bone metastases: From disease recognition to clinical practice

Abstract

Bone metastases, as one of the common types of metastatic tumors, have a great impact on the survival period and quality of life of patients. Bone metastases are usually characterized by bone destruction. Skeletal related events caused by bone destruction often lead to pain, pathological fractures and even paralysis. In this review, we provide a detailed explanation of bone metastases from the epidemiology, clinical features, pathogenesis, and recently developed clinical treatment viewpoints. We concluded that the incidence of bone metastases is increasing gradually, with serious clinical symptoms, complex pathogenesis and diverse clinical treatment. Tumor cells, immune cells, osteoblasts/osteoclasts and other cells as well as cytokines and enzymes all play a key role in the pathogenesis of bone metastases. We believe that the future treatment of bone metastases will be diversified and comprehensive. Some advanced technologies, such as nanomedicine, could be used for treatment, but this depends on understanding how disease occurs. With the development of treatment, the survival time and quality of life of patients will be improved.

Keywords: bone metastases; clinical practice; disease recognition; review; scope.

Figure 1

The role of different cell types in bone metastases.

Figure 2

Schematic diagram of the interaction between tumor cells and osteoblasts/osteoclasts in osteolytic bone metastases. In osteolytic lesions, tumor cells may secrete molecules such as DKK-1 to inhibit osteoblast Wnt signaling pathway and promote osteoclast function through RANK-RANKL signaling pathway. Osteoclasts may secrete IGF-1 and other molecules to promote tumor growth.DKK-1, Dickkopf-1; IFG-1, Insulin-like growth factor 1; RANK, Receptor Activator of NF-κB.

Figure 3

Typical mechanisms of action of key specific and non-specific immune cells in bone metastases. The red lines represent inhibitory effects.

Figure 4

The role of CAFs in the pathogenesis of bone metastases. The purple arrow represents an influence. EMT, epithelial-mesenchymal transition; PGE2, prostaglandin E2; EVs, extracellular vesicles; HGF, hepatocyte growth factor; VEGF, vascular endothelial growth factor.