Factors involved in cancer metastasis: a better understanding to “seed and soil” hypothesis

Abstract

Metastasis has intrigued researchers for more than 100 years. Despite the development of technologies and therapeutic strategies, metastasis is still the major cause of cancer-related death until today. The famous “seed and soil” hypothesis is widely cited and accepted, and it still provides significant instructions in cancer research until today. To our knowledge, there are few reviews that comprehensively and correlatively focus on both the seed and soil factors involved in cancer metastasis; moreover, despite the fact that increasingly underlying mechanisms and concepts have been defined recently, previous perspectives are appealing but may be limited. Hence, we reviewed factors involved in cancer metastasis, including both seed and soil factors. By integrating new concepts with the classic hypothesis, we aim to provide a comprehensive understanding of the “seed and soil” hypothesis and to conceptualize the framework for understanding factors involved in cancer metastasis. Based on a dynamic overview of this field, we also discuss potential implications for future research and clinical therapeutic strategies.

miR‐155 overexpression is followed by downregulation of its target gene, NFE2L2, and altered pattern of VEGFA expression in the liver of melanoma B16‐bearing mice at the premetastatic stage

“…39 Ensuing hypoxia and redox status alterations are considered as key components of the premetastatic remodelling of target organs. 40 An increase in the oxidative stress marker 2-OH-E + was observed in premetastatic tissues. 41 The expression of NFE2L2 was decreased in hepatocellular carcinoma and increased in alcoholic cirrhosis and end-stage liver disease.…”

“…The molecule NFE2L2 modulates antioxidant response and maintains cell redox homeostasis, controlling the expression of genes involved in the elimination of oxidants and electrophilic agents . Ensuing hypoxia and redox status alterations are considered as key components of the premetastatic remodelling of target organs . An increase in the oxidative stress marker 2‐OH‐E + was observed in premetastatic tissues .…”

Brain microvascular endothelial cell exosome–mediated S100A16 up‐regulation confers small‐cell lung cancer cell survival in brain

“…The hypothesis of "seed and soil" denotes that metastatic tumor cells could form secondary tumors only in permissive tissues with organ-specific soils (30). In other words, organ-specific metastasis may not only depend on the intrinsic abilities of cancer cells to cross biologic barriers, but also on metastatic microenvironments at distant organ, such as the microvascular system.…”

Long Noncoding RNAs in Osteosarcoma: Mechanisms and Potential Clinical Implications

“…A major role in the metastatic cascade plays the phenomenon of epithelial to mesenchymal transition (EMT) whereby epithelial cells lose their epithelial features and acquire mesenchymal cells traits which allow them to invade adjacent tissues and display migratory properties. The metastatic cascade is a multistep complex process and can be divided in the following phases: (1) invasion of the extracellular matrix (ECM) and degradation of ECM proteins through the activity of matrix metalloproteinases (MMPs), (2) intravasation, (3) resistance to anoikis and survival in the peripheral blood, (4) extravasation, and (5) seeding of a distant body site by clones of neoplastic cells with high metastatic potential [192,200,201]. A number of studies have shown the involvement of lncRNAs in the metastatic progression of osteosarcoma through modulation of metalloproteinase expression, especially MMP-2 and MMP-9 [202,203].…”