Combined Evaluation of MAP1LC3B and SQSTM1 for Biological and Clinical Significance in Ductal Carcinoma of Breast Cancer

Abstract

Breast cancer is the leading cause of cancer death in women worldwide. The microtubule-associated protein light chain 3B (MAP1LC3B) and adaptor sequestosome 1 (SQSTM1) are two major markers for autophagy. Increased protein levels of MAP1LC3B and SQSTM1 are considered to be causes of autophagy inhibition or activation in various types of cancers. However, the roles of MAP1LC3B and SQSTM1 in breast cancer are still not clear. Using a tissue microarray from 274 breast invasive ductal carcinoma (IDC) patients, we found that tumor tissues showed higher protein levels of MAP1LC3B and cytoplasmic SQSTM1 in comparison to those in adjacent normal tissues. Moreover, high levels of MAP1LC3B were associated with better survival, including disease-specific survival and disease-free survival (DFS) in IDC patients. Furthermore, high co-expression of MAP1LC3B and SQSTM1 was significantly associated with better DFS in IDC patients. Astonishingly, the autophagy inhibitor accumulated the protein levels of MAP1LC3B/SQSTM1 and enhanced the cytotoxic effects of cisplatin and paclitaxel in MCF7 and BT474 breast cancer cell lines, implying that autophagy inhibition might result in poor prognosis and chemosensitivity in IDC. Taken together, high co-expression of MAP1LC3B and SQSTM1 might serve as a potential diagnostic and prognostic biomarker for IDC patients.

Induction of Genes Implicated in Stress Response and Autophagy by a Novel Quinolin-8-yl-nicotinamide QN523 in Pancreatic Cancer

“…As clearly illustrated by Bru-seq trace diagrams (Figure ), QN523 increases the transcription of select autophagy-related genes WIPI1 (12.8-fold, Figure A), FAM129A (16.8-fold, Figure B), homocysteine-inducible ER protein with ubiquitin like domain 1 (HERPUD1) (9.8-fold, Figure C), GABARAPL1 (7.8-fold, Figure D), HMOX1 (13-fold, Figure E), and MAP1LC3B (6.8-fold, Figure F). WIPI1, GABARAPL1, and MAP1LC3B are well-established autophagy-related genes and relevant cancer markers at both gene and protein levels. − HERPUD1 is a part of the ER-associated degradation machinery involved in ubiquitin-dependent degradation of misfolded proteins in the ER . FAM129A an ATF4 target genes plays a direct role in autophagy. , Heme oxygenase (HMOX1) acts as a cytoprotective gene against several forms of cell death including autophagy .…”

Identification of microtubule-associated biomarker using machine learning methods in osteonecrosis of the femoral head and osteosarcoma

“…They could be significant contributors to the development of both diseases. Specifically, PRKCZ may participate in regulating tumor cell proliferation and invasion [ 42 ], PAK1 may affect tumor cell migration and invasion [ 43 ], MAP1LC3B may regulate cellular autophagy activity [ 44 ], and ANAPC5 may participate in regulating cellular mitotic activity [ 45 ]. Dysfunctions in the functions of these genes may affect tumor cell growth, metastasis, and bone tissue repair, thus influencing the development of OS and ONFH.…”