Davide Bertozzi [51] revealed a novel mechanism by which camptothecin inhibits cancer cell proliferation; acting as an inhibitor of DNA topoisomerase I, camptothecin can upregulate the expression of miR-17-5p and miR-155 in tumor cells, thereby suppressing the activity of HIF-1 alpha protein and effectively slowing the proliferation rate of cancer cells. The gene discussed is TOP1; the disease is cancer.