ZFAS1 and neoplasm: The oncogenic lncRNA ZFAS1, however, is directly repressed by p53, and regulated by p53 (and its microRNA genes, miR-135b-5p, miR-193a-3p, and miR-34b), so that when these tumor suppressors are present, they inhibit the expression of lncRNA ZFAS1 and thus inhibit PTC cell proliferation [22].