"Cancerous tumors release a substance that causes blood vessels in the surrounding tissues to grow into the tumor to provide it with nutrients. This process is known as"

Angiogenesis

Explanation:

Angiogenesis is one of the various stages of tumor formation. This process is initiated when tumor cells begins to divide spontaneously and uncontrollably.

To also ensure their continued survival, they induce blood vessels growth by allowing the secretion of various growth factors and proteins.

The new blood vessels growth ensures the supply of required nutrients and allow for the tumour expansion.

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