Fig. 3

PKM2 expression is upregulated in TNBC, and knockdown of PKM2 diminishes TNBC cell proliferation and metastasis both in vitro and in vivo. (A) Representative images of IHC staining of PKM2 in matched normal tissues (n = 60) and TNBC tissues (n = 60). Scale bar, 50 μm. (B) Quantitative analysis of PKM2 expression levels in matched normal tissue (Normal) and TNBC tissue (Tumor) samples. The data are presented as the mean ± SD. **P < 0.01. (C) Percentage of TNBC patients with high expression or low expression of PKM2 stratified according to lymph node status (N0 or N1–3) (n = 60); two-sided Fisher’s exact test, *P < 0.05. (D) PKM2 protein expression was detected by western blot in MDA-MB-231 and BT-549 cells infected with the Scr, PKM2 sh1, or sh2 lentivirus. GAPDH served as a loading control. (E) Cell proliferation was examined by CCK-8 assays in MDA-MB-231 and BT-549 cells infected with the Scr, PKM2 sh1, or sh2 lentivirus. The data are presented as the mean ± SD. ****P < 0.0001 compared to the Scr control group. (F) Colony formation assay of MDA-MB-231 and BT-549 cells with Scr control or PKM2 knockdown. The number of colonies is shown in the bar graph (right panels). The data are presented as the mean ± SD (n = 3). ***P < 0.001, ****P < 0.0001 compared to the Scr control group. (G) Representative images of the migration (top panels) and invasion (bottom panels) of MDA-MB-231 and BT-549 cells after Scr control or PKM2 knockdown. The data are presented as the mean ± SD (n = 5). ***P < 0.001, ****P < 0.0001 compared to the Scr control group. (H) Representative IHC staining of PKM2 in mammary tumor tissues from MMTV-PyMT (FVB background) mice injected with Scr, PKM2 sh1, and PKM2 sh2 AAVs. Scale bar, 25 μm. I-K Representative images of excised tumors (I), tumor growth curves (J), and tumor weights (K); representative H&E staining images of lungs (L); and the number of lung metastases (M) from MMTV-PyMT (FVB background) mice injected with Scr, PKM2 sh1, or sh2 AAVs. Scale bar, 100 μm. All data are presented as the mean ± SD (n = 6). ***P < 0.001, ****P < 0.0001 compared to the Scr control group