Aim: The present study explored the clinical significance of microRNA-22 (miR-22)
expression in lung squamous cell carcinoma and to explore the targeting relationship with vascular
endothelial growth factor receptor 3 (VEGFR3).
Methods: A total of 49 patients with lung squamous cell carcinoma who underwent surgical
treatment were selected. The expression of miR-22 was detected by fluorescence quantitative realtime
PCR (qPCR), the expression of VEGFR3 was detected by Western blotting assays, and D240
labeled microlymphatic vessels density (MLVD) was detected by immunohistochemistry (IHC).
Lung squamous cell carcinoma cell line SK-MES-1 was selected and the targeting relationship
between miR-22 and VEGFR3 was analyzed by double luciferase reporter gene assay. Western
blotting assays were used to detect the expression of vascular endothelial growth factor-D (VEGFD)
and D240 in the blank control group, empty vector transfection group, miR-22 transfection
group, miR-22 and VEGFR3 co-transfection group.
Results: The expression range of miR-22 in lung squamous cell carcinoma was 0.8-3.5. The
expression of miR-22 in lung squamous cell carcinoma was significantly different by tumor
maximum diameter, lymph node metastasis, vascular invasion and TNM stage. The expression of
miR-22 was linked to survival time. There was a negative correlation between miR-22 and
VEGFR3, miR-22 and MLVD. Double luciferase reporter gene assays showed that miR-22
reduced the luciferase activity of pGL3-VEGFR3-WT transfected cells. Compared with the control
group, the expression of VEGF-D and D2-40 in the miR-22 transfection group was significantly
decreased. However, VEGF-D and D240 in the miR-22 and VEGFR3 co-transfection group
reversed the changes.
Conclusion: We assumed that the abnormal expression of miR-22 in lung squamous cell
carcinoma may be involved in the development and progression of lung squamous cell carcinoma.
MiR-22 negatively regulated the target gene VEGFR3 to mediate lymphangiogenesis. The
expression of miR-22 may also be linked to the prognosis of the disease.