[miR-34b-3p regulates the angiogenesis of senescent endothelial cell]

OBJECTIVE

To investigate the effect of miR-34b-3p on the proliferation, migration and tube formation of senescent endothelial cell.

METHODS

Primary human umbilical vein endothelial cells (HUVECs) were cultured in vitro, and population doubling levels (PDLs) were calculated by passage. The young endothelial cell was defined as PDL8. The senescent endothelial cell was defined as PDL44. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was applied to detect the expression of miR-34b-3p in PDL8 and PDL44 HUVECs. miR-34b-3p mimic and inhibitor were transfected into PDL8 and PDL44 HUVECs. Then, cell counting kit-8 (CCK-8), transwell and tube formation assays were used to determine the proliferation, migration and tube formation of HUVECs, respectively.

RESULTS

miR-34b-3p was significantly up-regulated approximately 4.3 times in PDL44 HUVECs than that in PDL44 HUVECs (t=-4.528, P<0.05). The proliferation, migration, total tube length and branch points of miR-34b-3p in PDL8 HUVECs group were significantly higher approximately 1.2 (0.67/0.57), 1.2 (106/86), 1.4 (10 605/7 735) and 1.3 (41/31) times than that in PDL44 HUVECs group, respectively (t=3.237, 3.564, 5.165, 3.487, P<0.05 or P<0.01). Overexpression of miR-34b-3p had significantly inhibited proliferation, migration, total tube length and branch points approximately 2.2 (0.67/0.30), 2.3 (106/46), 1.6 (10 605/6 652) and 1.9 (41/22) times in PDL8 HUVECs, respectively (F=145.898, 53.026, 41.997, 36.341, all P<0.01). Repression of miR-34b-3p had significantly increased proliferation, migration, total tube length and branch points approximately 1.4 (0.77/0.57), 2.3 (198/86), 1.7 (13 073/7 735) and 2.3 (71/31) times in PDL44 HUVECs, respectively (F=14.815, 42.970, 167.063, 258.340, all P<0.01).

CONCLUSION

The high expression of miR-34b-3p in senescent HUVECs could impair the proliferation, migration and tube formation of senescent endothelial cell.

Axillary lymph node status, adjusted for pathologic complete response in breast and axilla after neoadjuvant chemotherapy, predicts differential disease-free survival in breast cancer

BACKGROUND

Our retrospective study in breast cancer patients evaluated whether integrating subtype and pathologic complete response (pcr) information into axillary lymph node restaging after neoadjuvant chemotherapy (nac) adds significance to its prognostic values.

METHODS

Patients included in the analysis had stage ii or iii disease, with post-nac axillary lymph node dissection (alnd), without sentinel lymph node biopsy before completion of nac, with definitive subtyping data and subtype-oriented adjuvant treatments. The ypN grading system was used to restage axillary lymph node status, and ypN0 was adjusted by pcr in both breast and axilla into ypN0(pcr) and ypN0(non-pcr). Univariate and multivariate survival analyses were performed.

RESULTS

Among the 301 patients analyzed, 145 had tumours that were hormone receptor-positive (hr+) and negative for the human epidermal growth factor receptor (her2-), 101 had tumours that were positive for her2 (her2+), and 55 had tumours that were triple-negative. The rate of pcr in both breast and axilla was 11.7%, 43.6%, and 25.5% respectively for the 3 subtypes. Compared with the non-pcr patients, the pcr patients had better disease-free survival (dfs) and overall survival (os): p = 0.002 for dfs and p = 0.011 for os. In non-pcr patients, dfs and os were similar in the ypN0(non-pcr) and ypN1 subgroups, and in the ypN2 and ypN3 subgroups. We therefore grouped the ypN grading results into ypN0(pcr) (n = 75), ypN0- 1(non-pcr) (n = 175), and ypN2-3 (n = 51). In those groups, the 3-year dfs was 98%, 91%, and 56%, and the 3-year os was 100%, 91%, and 82% respectively. The differences in dfs and os between those three subgroups were significant (all p < 0.05 in paired comparisons). Multivariate Cox regression showed that subtype and ypN staging adjusted by pcr were the only two independent factors predicting dfs.

CONCLUSIONS

Axillary lymph node status after nac, adjusted for pcr in breast and axilla, predicts differential dfs in patients without prior sentinel lymph node biopsy.