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Breast cancer affects 1 in 8 women in the United States. The American Cancer Society has estimated that in 2020 about 276,480 new cases of invasive breast cancer will be diagnosed in women. Cancer research has taken a turn in the last several decades to focus on new approaches to combat the disease. This project focuses on two approaches, siRNA and CRISPR/Cas9 that can have potential applications in cancer research. The first approach is a specific type of RNA interference (RNAi) that has been pursued due to its therapeutic potential in cancer research. In short, siRNA delivery is a method of targeting mRNA and reducing the protein expression in cancer cells. There are several advantages to siRNA. First, siRNA does not alter the genetic information of the cell. Second, nucleus penetration is not necessary. Third, siRNA is highly specific, which minimizes off-target effects. Lastly, due to the lack of transfection and insertion into chromosomes, siRNA could be viewed as a “gene therapy drug,” a characteristic more attractive for the pharmaceutical industry. Though, with these advantages comes one major disadvantage. siRNA is notoriously difficult to deliver to the targeted cells due to siRNA’s particular negatively-charged nature and instability. In order to overcome the cellular delivery challenge faced by siRNA, we have designed peptide lipid-associated nucleic acids (PLANAs) to enhance electrostatic interactions between siRNA and the cationic peptide and hydrophobic interactions with the phospholipid bilayer of the cell. The second approach is focused on utilizing CRISPR/Cas9 to target the gene that is causing unwanted overexpression of proteins in cancer. The CRISPR/Cas9 plasmid contains guide RNA (gRNA) that is designed to target a specific gene of interest. The CRISPR/Cas9 plasmid can then be employed to knockout the targeted gene. This method leads to permanent gene knockout, altering the chromosomal DNA of the cell. Similarly to siRNA, the gRNA in the CRISPR/Cas9 plasmid is negatively-charged, creating difficulty in cellular delivery. Thus, PLANAs were also utilized to enhance CRISPR/Cas9 delivery.