APOBEC3B and ovarian cancer: Although a direct comparison of expression levels between serous tumor samples and normal ovarian tissues is the point of debates, which has been as well discussed by the authors, the accompanied functional studies revealed a positive association between APOBEC3B expression in cancer tissues from 16 patients and elevated levels of transversion mutations, thus, suggesting a contributing role of APOBEC3B in genomic instability attributed to ovarian cancer.