Correction to: The Role of BiP and the IRE1α–XBP1 Axis in Rhabdomyosarcoma Pathology (Cancers, (2021), 13, 19, (4927), 10.3390/cancers13194927)

There was an error in the original publication [1]. Author name “Marek J. Los” should be corrected to “Marek J. Łos”. The post code in aff 7 should be corrected to 44-100. One of the antibodies information reported in “Section 2.2 Immunohistochemistry” was incorrect. Specifically, the catalog number for the anti-XBP1 antibody was incorrectly listed as ab96481 (Abcam). The correct antibody used in all experiments to detect XBP1 and sXBP1 was ab37152 (Abcam), a rabbit polyclonal antibody that detects both spliced (sXBP1, nuclear) and unspliced (XBP1, cytosolic) isoforms of XBP1. This correction does not alter the interpretation of the data but is important to ensure the transparency and reproducibility of the methods described. A correction has been made to Section 2.2 Immunohistochemistry: “TMA slides (5 μm thick) were deparaffinized in 60 °C for 30 min and subsequently rehydrated in xylene with a gradient alcohol series. Heat-mediated antigen retrieval (0.01 M sodium citrate buffer, pH 6.0) was performed as described previously [22,26,27]. In order to eliminate background interference, the slides were washed with phosphate-buffered saline (PBS) and blocked with blocking solution (1.5 mL Maleic Acid Buffer, 0.5 mL FBS, 0.5 mL stock blocking solution, 50 μL 10% Tween-20, and 2.5 mL PBS) at room temperature for 30 min. After washing with PBS, the slides were incubated in freshly prepared 3% H₂O₂ to eliminate endogenous hydrogen peroxidases. The TMA slides were incubated with Avidin blocking solution (Vector SP-2001, 15 min) and then with Biotin blocking solution (Vector WP-2001, 15 min). Next, the slides were incubated overnight (4 °C) with mouse mAb against IRE1 (1:100; cat. no. ab96481; Abcam), rabbit mAb against BiP (1:200; cat. no. #3177, Cell Signaling; Danvers, MA USA), and rabbit polyclonal antibody against cytosolic and nuclear XBP1 (1:200; cat. no. ab37152; Abcam). Following thorough washing with PBS, the slides were incubated with biotinylated secondary antibody (corresponding to the primary antibody) for 1 h at room temperature, washed with PBS, and incubated with horseradish peroxidase-labeled streptavidin (1:200) for 30 min at room temperature. Finally, the slides were incubated with a 3,3′-diaminobenzidine-peroxidase substrate for 2 min at room temperature and counterstained with Mayer Hematoxylin (Vector H-3404; 10 drops in 1.25 mL PBS) for 1–4 min. In order to exclude any nonspecific staining of the secondary antibodies, negative controls were performed without the addition of any primary antibody.” A correction has been made to Data Availability Statement: Data Availability Statement: The data supporting the findings of this study are available in the Supplementary Material (Table S1). To ensure transparency and allow readers to directly review the original immunohistochemistry data, all raw images, including those presented in Figures 1–4, have been deposited in the Dryad digital repository. These can be accessed via the following DOI: https://datadryad.org/dataset/doi:10.5061/dryad.d2547d8c6. Data Availability Statement: The data supporting the findings of this study are available in the Supplementary Material (Table S1). To ensure transparency and allow readers to directly review the original immunohistochemistry data, all raw images, including those presented in Figures 1–4, have been deposited in the Dryad digital repository. These can be accessed via the following DOI: https://datadryad.org/dataset/doi:10.5061/dryad.d2547d8c6. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.