Recent studies have discovered several
microRNAs (
miRNAs/miRs) as
biomarkers for the prediction of
ovarian cancer by detecting
miRNA profiles in serum samples from healthy volunteers and patients with
ovarian cancer. However, whether and how these
miRNAs are involved in
tumorigenesis is not known. In the present study, the expression of miR-665, a recently discovered
biomarker for
ovarian cancer, was upregulated in
tumor tissues from patients with
ovarian cancer compared with normal tissues. Inhibition of miR-665 inhibited cell proliferation ability and inactivated MAPK/ERK signaling of
ovarian cancer cells. Using bioinformatics analysis,
Src kinase signaling inhibitor 1 (SRCIN1) was predicted as a potential target gene of miR-665. Reverse transcription-quantitative PCR and western blotting showed that SRCIN1 expression was repressed by miR-665 in
ovarian cancer cells. In addition, a dual
luciferase activity assay showed that SRCIN1 was a target gene of miR-665. Silencing of SRCIN1 could reverse the cell growth arrest, which was induced by the miR-665 inhibitor. Moreover, miR-665 levels were negatively correlated with SRCIN1
mRNA levels in
tumor tissues from patients with
ovarian cancer. In conclusion, the present data suggested that miR-665 functioned as an oncogene in
ovarian cancer by directly repressing the expression of SRCIN1.