A 4-copy branched peptide represented by a formula of (XA-XB-XC-XD-X1)4>(K-X2)2>K-X3. XA and XC separately represent an uncharged polar amino acid XB and XD separately represent an alkaline amino acid >K- represents lysine comprising two free activated amino groups for amino acid addition condensation reactions X1 and X2 separately represents an amino acid sequence comprising between 0 and 5 random amino acids, and X1 and X2 are the same, different, or absent and X3 is a sequence comprising between 1 and 4 random amino acids. The peptide is capable of inhibiting tumor growth and enhancing immunity.
