Corrigendum to "Chaperone-Mediated Autophagy Markers LAMP2A and HSC70 Are Independent Adverse Prognostic Markers in Primary Resected Squamous Cell Carcinomas of the Lung".

[This corrects the article DOI: 10.1155/2020/8506572.]

Her2-Targeted Therapy Induces Autophagy in Esophageal Adenocarcinoma Cells

Esophageal adenocarcinoma (EAC) is a highly lethal cancer type with an overall poor survival rate. Twenty to thirty percent of EAC overexpress the human epidermal growth factor receptor 2 (Her2), a transmembrane receptor tyrosine kinase promoting cell growth and proliferation. Patients with Her2 overexpressing breast and gastroesophageal cancer may benefit from Her2 inhibitors. Therapy resistance, however, is well documented. Since autophagy, a lysosome-dependent catabolic process, is implicated in cancer resistance mechanisms, we tested whether autophagy modulation influences Her2 inhibitor sensitivity in EAC. Her2-positive OE19 EAC cells showed an induction in autophagic flux upon treatment with the small molecule Her2 inhibitor Lapatinib. Newly generated Lapatinib-resistant OE19 (OE19 LR) cells showed increased basal autophagic flux compared to parental OE19 (OE19 P) cells. Based on these results, we tested if combining Lapatinib with autophagy inhibitors might be beneficial. OE19 P showed significantly reduced cell viability upon double treatment, while OE19 LR were already sensitive to autophagy inhibition alone. Additionally, Her2 status and autophagy marker expression (LC3B and p62) were investigated in a treatment-naïve EAC patient cohort (n = 112) using immunohistochemistry. Here, no significant correlation between Her2 status and expression of LC3B and p62 was found. Our data show that resistance to Her2-directed therapy is associated with a higher basal autophagy level, which is not per se associated with Her2 status. Therefore, we propose that autophagy may contribute to acquired resistance to Her2-targeted therapy in EAC, and that combining Her2 and autophagy inhibition might be beneficial for EAC patients

El subjuntivo y la mente

[This corrects the article DOI: 10.1371/journal.pone.0197610.]

No statistically significant independent prognostic factor was identified in a neo-adjuvant chemotherapy treated EAC cohort.

<p>HR–Hazard Ratio.</p

Comparison of expression of autophagy markers LC3B and p62 in primary resected and neo-adjuvant chemotherapy (nCTX) treated EAC cohorts.

<p>Significance was set to 0.05. Statistically significant p-values are shown in bold.</p

Differential response to paclitaxel is not associated with differential autophagy regulation.

<p>OE19, FLO-1, OE33 and SK-GT-4 were treated with paclitaxel, in a final concentration of 20nM, for 24hr with or without the addition of the late stage autophagy inhibitor BafA (200nM) for the last 2hr of the 24hr paclitaxel treatment. LC3B was visualized using Western blotting; total protein was used as loading control. (a) Representative blots of LC3B in all four cell lines, the LC3B-I isoform is not equally visible in all cell lines at the given exposures. (b) Quantification of the LC3B-II normalized to the total protein. Error bars indicate the standard deviation of three independent experiments. Statistical significance was not reached when conditions where compared to one another. (c) WIP1 and LC3B mRNA was assessed via qPCR upon treatment with paclitaxel at 20nM and 40nM for 24hr in OE19 and OE33. Nutrient starvation, achieved with 6hr incubation with EBSS, was included in the experimental setup as a positive control for a known autophagy inducer. Fold change was normalized to mRNA levels of housekeeping gene HBSS. The DMSO equivalent of the highest final concentration of paclitaxel was added to the untreated condition as vehicle control and relative values were normalized to the untreated controls which were set to 1. Error bars indicate the standard deviation of three independent experiments.</p

Kaplan-Meier survival curves for autophagy markers in post-treatment tumor tissue of a neo-adjuvant EAC cohort.

<p>(A) LC3B dot-like staining patterns, (B) p62 dot-like staining patterns (C) groupings of LC3B dot-like/p62 dot-like-cytoplasmic expression: Low LC3B/low p62 (LL), low LC3B/high p62 (LH), high LC3B/low p62 (HL) and high LC3B/high p62 (HH); and (D) LC3B dot-like/p62 dot-like-cytoplasmic expression LH versus remainder of all other cases. For each curve the p-value is displayed on the bottom right-hand corner.</p

EAC cell lines exhibit differential response to paclitaxel treatment.

<p>Relative cell viability upon treatment with paclitaxel in increasing concentrations (0, 2.5, 5, 10, 20 and 40nM) was assessed using the Alamar Blue assay in OE19, FLO-1, OE33 and SK-GT-4 after 24hr (a) and 48hr (b). Error bars indicate the standard deviation of three independent experiments. The DMSO equivalent of the highest final concentration was added to the untreated condition as vehicle control and relative toxicity values were normalized to the untreated controls which were set to 100%.</p