Explanation:

• MicroRNAs (miRNAs) are short noncoding RNAs containing 20–24 nucleotides that participate in virtually all biological pathways in animals.
• The miRNAs affect cancer growth through inhibiting or enhancing the functions of certain proteins.
• The miRNAs associated with cancer are called ‘Oncomirs’. Many of the Oncomirs affect cancer by suppressing the performance of tumour-suppressing agents. Some of them can prevent the growth and spread of cancer cells and yet others prevent tumour growth itself. Hence both statements are correct.