Vasculogenic mimicry (VM) is a brand-new tumour vascular paradigm independent of angiogenesis that describes the specific capacity of aggressive cancer cells to form vessel-like networks that provide adequate blood supply for tumour growth. A variety of molecule mechanisms and signal pathways participate in VM induction. Additionally, cancer stem cell and epithelial-mesenchymal transitions are also shown to be implicated in VM formation. As a unique perfusion way, VM is associated with tumour invasion, metastasis and poor cancer patient prognosis. Due to VM's important effects on tumour progression, more VM-related strategies are being utilized for anticancer treatment. Here, with regard to the above aspects, we make a review of advanced research on VM in cancer.

Purpose Cell size is a fundamental characteristic of all tissues, and changes in cell size in cancer reflect tumor status and response to treatments, such as apoptosis and cell‐cycle arrest. Unfortunately, cell size can currently be obtained only by pathological evaluation of tumor tissue samples obtained invasively. Previous imaging approaches are limited to preclinical MRI scanners or require relatively long acquisition times that are impractical for clinical imaging. There is a need to develop cell‐size imaging for clinical applications. Methods We propose a clinically feasible IMPULSED (imaging microstructural parameters using limited spectrally edited diffusion) approach that can characterize mean cell sizes in solid tumors. We report the use of a combination of pulse sequences, using different gradient waveforms implemented on clinical MRI scanners and analytical equations based on these waveforms to analyze diffusion‐weighted MRI signals and derive specific microstructural parameters such as cell size. We also describe comprehensive validations of this approach using computer simulations, cell experiments in vitro, and animal experiments in vivo and demonstrate applications in preoperative breast cancer patients. Results With fast acquisitions (~7 minutes), IMPULSED can provide high‐resolution (1.3 mm in‐plane) mapping of mean cell size of human tumors in vivo on clinical 3T MRI scanners. All validations suggest that IMPULSED provides accurate and reliable measurements of mean cell size. Conclusion The proposed IMPULSED method can assess cell‐size variations in tumors of breast cancer patients, which may have the potential to assess early response to neoadjuvant therapy.

Vasculogenic mimicry ( VM ) is a vascular‐like structure which can mimic the embryonic vascular network pattern to nourish the tumour tissue. As a unique perfusion way, VM is correlated with tumour progression, invasion, metastasis and lower 5‐year survival rate. Notably, epithelial‐mesenchymal transition ( EMT ) regulators and EMT ‐related transcription factors are highly up‐regulated in VM ‐forming tumour cells, which demonstrated that EMT may play a crucial role in VM formation. Therefore, the up‐regulation of EMT ‐associated adhesion molecules and other factors can also make a contribution in VM ‐forming process. Depending on these discoveries, VM and EMT can be utilized as therapeutic target strategies for anticancer therapy. The purpose of this article is to explore the advance research in the relationship of EMT and VM and their corresponding mechanisms in tumorigenesis effect.

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