The unique catalytic properties of PSAT1 mediate metabolic adaptation to glutamine blockade

Qiu, Yijian, Stamatatos, Olivia T, Hu, Qingting, Ruiter Swain, Jed, Russo, Suzanne, Sann, Ava, Costa, Ana SH, Violante, Sara, Spector, David L, Cross, Justin R, Lukey, Michael J (August 2024) The unique catalytic properties of PSAT1 mediate metabolic adaptation to glutamine blockade. Nature Metabolism, 6 (8). pp. 1529-1548. ISSN 2522-5812 (Public Dataset)

Abstract

Cultured cancer cells frequently rely on the consumption of glutamine and its subsequent hydrolysis by glutaminase (GLS). However, this metabolic addiction can be lost in the tumour microenvironment, rendering GLS inhibitors ineffective in the clinic. Here we show that glutamine-addicted breast cancer cells adapt to chronic glutamine starvation, or GLS inhibition, via AMPK-mediated upregulation of the serine synthesis pathway (SSP). In this context, the key product of the SSP is not serine, but α-ketoglutarate (α-KG). Mechanistically, we find that phosphoserine aminotransferase 1 (PSAT1) has a unique capacity for sustained α-KG production when glutamate is depleted. Breast cancer cells with resistance to glutamine starvation or GLS inhibition are highly dependent on SSP-supplied α-KG. Accordingly, inhibition of the SSP prevents adaptation to glutamine blockade, resulting in a potent drug synergism that suppresses breast tumour growth. These findings highlight how metabolic redundancy can be context dependent, with the catalytic properties of different metabolic enzymes that act on the same substrate determining which pathways can support tumour growth in a particular nutrient environment. This, in turn, has practical consequences for therapies targeting cancer metabolism.

Item Type: Paper
Subjects: diseases & disorders > cancer
diseases & disorders
diseases & disorders > neoplasms
organism description > animal
diseases & disorders > cancer > cancer types > breast cancer
organism description > animal > mammal
organism description > animal > mammal > rodent > mouse
organism description > animal > mammal > rodent
diseases & disorders > cancer > cancer types
CSHL Authors:
Communities: CSHL Cancer Center Program > Cellular Communication in Cancer Program
CSHL Cancer Center Program > Gene Regulation and Inheritance Program
CSHL labs > Spector lab
CSHL labs > Lukey lab
CSHL Cancer Center Program
SWORD Depositor: CSHL Elements
Depositing User: CSHL Elements
Date: August 2024
Date Deposited: 03 Sep 2024 12:58
Last Modified: 03 Sep 2024 12:58
Related URLs:
Dataset ID:
URI: https://repository.cshl.edu/id/eprint/41646

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