Mechanism of drug resistance to first-line chemotherapeutics mediated by
TXNDC17 in neuroblastomas
Abstract
The prognosis of high-risk neuroblastomas (NB) that are resistant to
first-line induction chemotherapy is relatively poor. This study
explored the mechanism of resistance to first-line chemotherapeutics
mediated by TXNDC17 and its potential solutions in NB. The genetic and
clinical data of patients with NB were obtained from the Therapeutically
Applicable Research to Generate Effective Treatments dataset. TXNDC17
and BECN1 expressions in NB cells were up- and downregulated by
transfection with plasmids and shRNA, respectively. Autophagy-related
proteins were detected by western blot. Cell viability was determined
using cell proliferation and toxicity experiments. Apoptotic cells were
detected using flow cytometry. Overall, 1076 pediatric and adolescent
patients with NB were enrolled in this study. The 10-year overall
survival (OS) rates and event-free survival (EFS) rates for the patients
with mutation of BECN1 were 37.4% ± 9.1% and 34.5% ± 8.8%,
respectively. For patients with mutation of TXNDC17, the 10-year OS and
EFS were 41.4% ± 5.9% and 24.3% ± 5.1%, respectively, which were
significantly lower than those in the unaltered group. The
overexpression of BECN1 and TXNDC17 reduced NB sensitivity to cisplatin
(DDP), etoposide (VP16), and cyclophosphamide (CTX). Autophagy mediated
by BECN1 was regulated by TXNDC17, and this process was involved in the
resistance to DDP, VP16, and CTX in NB. Suberoylanilide hydroxamic acid
(SAHA) can enhance the sensitivity of NB cells to chemotherapeutics by
inhibiting TXNDC17, ultimately decreasing autophagy-mediated
chemoresistance. Acquired resistance to first-line chemotherapeutics was
associated with autophagy mediated by BECN1 and regulated by TXNDC17,
which can be reversed by SAHA.