Fig. 2

Restoration of the miR-655 plasma levels could suppress tumour growth and lymph node metastasis in vivo. a Investigation into whether miR-655 could suppress tumour growth in vivo. The popliteal lymph node metastasis model was used to assess the therapeutic effect of miR-655 for lymph node metastasis. Seven days after the injection of KYSE790 cells into the footpads, tumour development at the injection site was visually confirmed every 7 days. The miR-655 or negative control mimic with atelocollagen was subcutaneously injected into the ventral surface of the lower flank region, which is far from the region injected with cancer cells, and these treatments continued weekly for three weeks after the initial treatment. The treatment with miR-655 mimic significantly suppressed tumour growth on the footpads compared with the negative control mimic. b Comparison of the plasma miR-655 levels between mice treated with miR-655 mimic and treated with negative control mimic. The plasma levels of miR-655 were significantly higher in mice treated with miR-655 mimic than in mice treated with negative control mimic. c Investigation into whether treatment with miR-655 mimic could suppress lymph node metastasis in vivo. To diagnose the lymph node metastasis, we resected the popliteal lymph node on the affected side and sectioned each lymph node into three slices. Lymph node metastasis was diagnosed by hematoxylin–eosin staining. The proportion of lymph node metastasis was significantly lower in mice treated with miR-655 mimic than in mice treated with negative control mimic. d Blood data analyses reflecting potential side effects following miR-655 treatment. There were no side effects in blood-based parameters of organ disorders such as creatinine (Cre), aspartate aminotransferase (AST), alanine aminotransferase (ALT), amylase (AMY), and total bilirubin (T-Bil)