First, let's cube all components, i.e. multiply everything by itself 3 times

(2x^-3yz⁵)³ =

(222x^-3x^-3x^-3yyyz⁵z⁵z⁵)

now we combine like terms
(8x^-9y³z¹⁵)

and finally, we'll rewrite this
remember, a negative exponent says 'it's on the wrong side'

(8y³z¹⁵) / x⁹