Describes NUAgo’s underlying technology, toxic 6-mer sequences, are functionally active in ovarian cancer cells and patient samples treated with platinum (Pt)-base chemotherapy agents, first-line in ovarian cancer. Finding that an increase in RISC-bound (active) miRNAs carrying toxic 6mer seeds and a decrease in miRNAs with nontoxic seeds. Pt-resistant cells did not exhibit this Pt induced toxicity shift but retained sensitivity to death mediated by siRNAs carrying toxic 6mer seeds. Analysis of active miRNAs in OC patient samples revealed that miRNA 6mer seed toxicity ratios were predictive of treatment outcomes. Offering a potential diagnostic in identifying Pt-resistance in patients. These results argue that 6mer seed toxicity can be exploited to treat patients with Pt-resistant OC