Combined evaluation of LC3B puncta and HMGB1 expression predicts residual risk of relapse after adjuvant chemotherapy in breast cancer

Autophagy. 2015;11(10):1878-90. doi: 10.1080/15548627.2015.1082022.


In spite of adjuvant chemotherapy, a significant fraction of patients with localized breast cancer (BC) relapse after optimal treatment. We determined the occurrence of cytoplasmic MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3B)-positive puncta, as well as the presence of nuclear HMGB1 (high mobility group box 1) in cancer cells within surgical BC specimens by immunohistochemistry, first in a test cohort (152 patients) and then in a validation cohort of localized BC patients who all received adjuvant anthracycline-based chemotherapy (1646 patients). Cytoplasmic LC3B(+) puncta inversely correlated with the intensity of SQSTM1 staining, suggesting that a high percentage cells of LC3B(+) puncta reflects increased autophagic flux. After setting optimal thresholds in the test cohort, cytoplasmic LC3B(+) puncta and nuclear HMGB1 were scored as positive in 27.2% and 28.6% of the tumors, respectively, in the validation cohort, while 8.7% were considered as double positive. LC3B(+) puncta or HMGB1 expression alone did not constitute independent prognostic factors for metastasis-free survival (MFS) in multivariate analyses. However, the combined positivity for LC3B(+) puncta and nuclear HMGB1 constituted an independent prognostic factor significantly associated with prolonged MFS (hazard ratio: 0.49 95% confidence interval [0.26-0.89]; P = 0.02), and improved breast cancer specific survival (hazard ratio: 0.21 95% confidence interval [0.05-0.85]; P = 0.029). Subgroup analyses revealed that within patients with poor-prognosis BC, HMGB1(+) LC3B(+) double-positive tumors had a better prognosis than BC that lacked one or both of these markers. Altogether, these results suggest that the combined positivity for LC3B(+) puncta and nuclear HMGB1 is a positive predictor for longer BC survival.

Keywords: HMGB1; LC3; breast cancer; histology; pathology; prognostic; tumor microarray.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autophagy / genetics
  • Autophagy / physiology*
  • Biomarkers, Tumor / metabolism
  • Breast Neoplasms / pathology
  • Breast Neoplasms / therapy*
  • Chemotherapy, Adjuvant / methods
  • Female
  • Gene Expression Regulation, Neoplastic / physiology
  • HMGB1 Protein / metabolism*
  • Humans
  • Microtubule-Associated Proteins / metabolism*
  • Recurrence
  • Risk Factors


  • Biomarkers, Tumor
  • HMGB1 Protein
  • MAP1LC3B protein, human
  • Microtubule-Associated Proteins