Methods are provided for making an RNA molecule derived from non-coding chimeric mitochondrial RNAs (ncmtRNAs), in particular antisense non-coding chimeric mitochondrial RNAs (ASncmtRNAs), compositions containing the isolated RNA molecule, methods of causing apoptosis in a cancer cell by contacting the cell with the RNA molecule, and methods of treating cancers by administering the RNA molecule to a subject in need thereof.