Combined evaluation of LC3B puncta and HMGB1 expression predicts residual risk of relapse after adjuvant chemotherapy in breast cancer.
Fiche publication
Date publication
octobre 2015
Auteurs
Membres identifiés du Cancéropôle Est :
Dr ARNOULD Laurent, Pr FUMOLEAU Pierre, Pr GHIRINGHELLI François, Dr LADOIRE Sylvain
Tous les auteurs :
Ladoire S, Penault-Llorca F, Senovilla L, Dalban C, Enot D, Locher C, Prada N, Poirier-Colame V, Chaba K, Arnould L, Ghiringhelli F, Fumoleau P, Spielmann M, Delaloge S, Poillot ML, Arveux P, Goubar A, Andre F, Zitvogel L, Kroemer G
Lien Pubmed
Résumé
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.
Référence
Autophagy. 2015 Oct 3;11(10):1878-90