Arsenic induces dysfunctional autophagy via dual regulation of mTOR pathway and Beclin1-Vps34/PI3K complex in MLTC-1 cells.

•Arsenic exposure caused a significant accumulation of autophagosomes in MLTC-1 cells.•Arsenic up-regulated autophagic markers including LC3, Atg7, Beclin1 and Vps34 expressions.•Arsenic enhanced the transcript levels of mTOR-downstream genes and Beclin1-Vps34/PI3K complex associated members.•Silencing of Beclin1, and inhibition of Vps34/PI3K and mTOR affected the As-induced autophagosomes formation.•Arsenic blocked autophagosomes degradation by impaired function of lysosomes.