mir-638 microrna precursor family mir-638 microrna precursor family in molecular biology mir-638 microrna is a short rna molecule. micrornas function to regulate the expression levels of other genes by several mechanisms. mir-638identifierssymbolmir-638rfamrf00978 mirbase familymipf0000486other datarna typemicrornadomain(s)eukaryota;pdb structurespdbe expression in lupus nephritis mir-638 has been implicated in the pathogenesis of lupus nephritis (ln), with intra-renal expression levels differing between normal and lupus nephritis patients. the degree of difference in expression levels further correlates with the degree of disease severity in each ln patient. mir-638 and gastric cancer mir-638 levels are significantly downregulated in gastric cancer cell lines, along with deregulation of 23 other mirnas. thus mir-628 is likely to be involved in the development and progression of gastric cancer. further applications mir-638 has additionally been found to be upregulated in the k562 leukaemic cell line.