Correction: Methylglyoxal, a glycolysis metabolite, triggers metastasis through MEK/ERK/SMAD1 pathway activation in breast cancer (vol 21, 11, 2019)

After the publication of the Original Article, the authors were notified by a reader about an error in Fig. 5. In panel 5B right, P-ERK detection in MDA-MB-468 using Western blot was duplicated, resulting in identical images presented in panel 5 C right. The authors acknowledged that the inclusion of identical images in these figures was an unfortunate mistake. The duplication seemed to have occurred while selecting images from the dedicated folder, where MDA-MB-468 western blots were classified. The authors have since retrieved the images corresponding to ERK detection in MDA-MB-468 cells upon the depletion of GLO1. The authors wanted to further point out that the images in panel 5 C right were well-attributed. Consequently, there are no changes to panel 5 C right. Methylglyoxal (MG) stress induces (hyper)activation of the mitogen-activated protein kinase (MAPK) signaling pathway in breast cancer cells. a Transforming growth factor (TGF)βR1, P-SMAD2/3 and SMAD4 protein levels in glyoxalase 1 (GLO1)-depleted MDA-MB-231 cells. Cells were treated with TGFβ 2.5 ng/ml for 2 h where indicated. b P-MEK1/2, MEK2, P-ERK and ERK expression in GLO1-silenced MDA-MB-231 and MDA-MB-468 cells cultured without serum for 24 h. c P-MEK1/2, MEK2, P-ERK and ERK protein levels in MDA-MB-231 and MDA-MB-468 cells treated with MG at the indicated concentrations for 3h in serum-free medium. d P-MEK1/2, MEK2, P-ERK and ERK expression in GLO1-silenced MDA-MB-231 and MDA-MB-468 cells treated with carnosine for 24 h in serum-free medium. All immunoblots were quantified by densitometric analysis and normalized for β-actin. Numbers represent fold increase relative to the condition shown with bold number. Western blot is representative of three independent experiments. e Migration ability toward serum of MDA-MB-231 shGLO1 cells pre-treated with MEK inhibitor, U0126 (10 μM, 3 h), was assessed using Transwell filters. Representative filters are shown for each condition. Scale bar represents 400 μm. f Quantification of migration assays of GLO1-silenced MDA-MB-231 cells treated with U0126. g Tenascin C, COL6A3, lumican and COL4A3 messenger RNA (mRNA) levels in GLO1-depleted MDA-MB-231 cells treated with U0126 for 3 h in serum-free medium were assessed by qRT-PCR. Data were analyzed using two-way analysis of variance followed by Bonferroni post-hoc test and are shown as mean values ± SEM of three independent experiments. *p < 0.05, **p < 0.01 and ***p < 0.001 Corrected Fig. 5: Methylglyoxal (MG) stress induces (hyper)activation of the mitogen-activated protein kinase (MAPK) signaling pathway in breast cancer cells. a Transforming growth factor (TGF)βR1, P-SMAD2/3 and SMAD4 protein levels in glyoxalase 1 (GLO1)-depleted MDA-MB-231 cells. Cells were treated with TGFβ 2.5 ng/ml for 2 h where indicated. b P-MEK1/2, MEK2, P-ERK and ERK expression in GLO1-silenced MDA-MB-231 and MDA-MB-468 cells cultured without serum for 24 h. c P-MEK1/2, MEK2, P-ERK and ERK protein levels in MDA-MB-231 and MDA-MB-468 cells treated with MG at the indicated concentrations for 3h in serum-free medium. d P-MEK1/2, MEK2, P-ERK and ERK expression in GLO1-silenced MDA-MB-231 and MDA-MB-468 cells treated with carnosine for 24 h in serum-free medium. All immunoblots were quantified by densitometric analysis and normalized for β-actin. Numbers represent fold increase relative to the condition shown with bold number. Western blot is representative of three independent experiments. e Migration ability toward serum of MDA-MB-231 shGLO1 cells pre-treated with MEK inhibitor, U0126 (10 μM, 3 h), was assessed using Transwell filters. Representative filters are shown for each condition. Scale bar represents 400 μm. f Quantification of migration assays of GLO1-silenced MDA-MB-231 cells treated with U0126. g Tenascin C, COL6A3, lumican and COL4A3 messenger RNA (mRNA) levels in GLO1-depleted MDA-MB-231 cells treated with U0126 for 3 h in serum-free medium were assessed by qRT-PCR. Data were analyzed using two-way analysis of variance followed by Bonferroni post-hoc test and are shown as mean values ± SEM of three independent experiments. *p < 0.05, **p < 0.01 and ***p < 0.001 The correction does not affect the results and conclusions of the original article. The authors thank the reader for pointing out the errors and apologize for any inconvenience caused by this. The original article has been corrected.