Latency-associated nuclear antigen (LANA) promotes ferroptosis by
suppressing Nrf2 and upregulating MDM2
Abstract
Ferroptosis is a recently discovered iron-dependent form of programmed
cell death, characterized by the accumulation of lipid peroxidation.
Latency-associated nuclear antigen (LANA) plays a crucial role in
ensuring the survival and proliferation of cells infected with Kaposi’s
sarcoma-associated herpesvirus (KSHV). In this study, we investigated
the effects of LANA on ferroptosis. Surprisingly, we discovered that
LANA promotes ferroptosis, with its downregulation diminishing and
upregulation enhancing this process. LANA itself did not alter
intracellular reactive oxygen species (ROS) levels; it modulated ROS
levels in response to ferroptosis inducers. Cells with reduced LANA
levels exhibited significantly elevated ROS levels, whereas cells
overexpressing LANA showed lower ROS levels. LANA suppressed the
expression of genes crucial for ferroptosis resistance, such as
glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1
(FSP1). Additionally, LANA inhibited nuclear factor erythroid 2-related
factor 2 (Nrf2) expression, impeding its nuclear translocation, while
upregulating the expression of mouse-double minute 2 (MDM2). Inhibitors
targeting Nrf2 and MDM2 partially negated the effects of LANA knockdown
and overexpression, respectively, on ferroptosis. These findings
suggested that LANA promotes ferroptosis and implyed that inducing
ferroptosis may represent a new therapeutic strategy in treating
KSHV-related tumors.