HFE-mimetics for the treatment of ASS1-dysregulated cancers

Primary supervisor: Peter Szlosarek, Queen Mary University of London

Secondary supervisor: Roberto Bellelli, Queen Mary University of London

Project

Purpose: To identify upstream targets of pegargiminase activity in HFE mutant arginine-dependent thoracic cancer cell lines with the aim of developing novel HFE-mimetics for cancer therapy.

Introduction

Loss of the urea cycle and rate-limiting enzyme for arginine biosynthesis, argininosuccinate synthetase 1 (ASS1) drives tumorigenesis by enhancing tumor cell proliferation, invasion and metastasis, and also impacting tumour inflammation and immunity (Delage et al, 2010, Allen et al, 2014). Our studies over the last 25 years have validated arginine deprivation using pegylated arginine deiminase (ADI-PEG20, pegargiminase) as a novel therapy for cancer focusing on aggressive ASS1LOW hard-to-treat cancers, with a proven survival benefit in patients with mesothelioma in two randomised studies, the phase 2 ADAM study of ADI-PEG20 monotherapy versus best-supportive care, and the double-blind, placebo-controlled phase 2-3 ATOMIC-Meso trial (Szlosarek et al, 2017, 2024) of pegargiminase-chemotherapy versus placebo-chemotherapy. The ATOMIC-Meso also identified a patient cohort of long-term responders and survivors treated weekly for two years with pegargiminase-based chemotherapy (with none on placebo-chemotherapy over the same period). This small cohort of patients harbored variants in the HFE (High Fe2+) gene which codes for the human homeostatic iron regulator protein and leads to iron overload in homozygotes (i.e. C282Y only) diagnosed with hereditary haemochromatosis (HH), but not in heterozygotes (C282Y and/or H63D) (Szlosarek et al, 2026). Our bedside-to-bench studies have confirmed enhanced sensitivity of HFE variants to pegargiminase on an ASS1-deficient background in mesothelioma and thoracic cancer cell lines. Here, we propose to identify HFE-mimetics that would be used either alone or in conjunction with pegargiminase to enhance chemo and immuno-therapies for hard-to-treat cancers. Moreover, since HFE mutations are heritable, this novel treatment paradigm offers a novel approach for both adult and paediatric arginine-dependent (ASS1 dysregulated) cancers.

Methodology and Materials

We will employ a CRISPR-Cas9 drop out screen using the Cancer Research UK Functional Genomic Centre in Cambridge to identify interacting partners in HFE mutant and parental mesothelioma (biphasic MSTO) and thoracic cancer (p53-mutant H1299 NSCLC) cell lines. Validation of top hits will be performed using qPCR, western blotting, gene overexpression/siRNA and pharmacological modulators where indicated.

References

1. Delage B, Fennell DA, Nicholson LJ, McNeish IA, Lemoine NR, Crook T, Szlosarek PW. Arginine deprivation and argininosuccinate synthetase expression for the treatment of human cancer. Int J Cancer 2010; 126(12):2762-72.
2. Allen M, Luong P, Hudson C, Leyton J, Delage B, Ghazaly E, Cutts R, Yuan M, Syed N, Lo Nior C, Lattanzio L, Chmielewska-Kassassir M, Tomlinson I, Roylance R, Whitaker HC, Warren AY, Neal D, Frezza C, Beltran L, Chelala C, Jones RL, Wu BW, Bomalaski JS, Jackson RC, Lu YJ, Crook T, Lemoine NR, Mather S, Foster J, Sosabowski J, Avril N, Li CF, Szlosarek PW. Prognostic and therapeutic impact of argininosuccinate synthase-1 control in bladder cancer as monitored longitudinally by PET imaging. Cancer Res 2014; 74(3):896-907.
3. Szlosarek PW, Steele JP, Nolan L, Gilligan D, Taylor P, Spicer J, Lind M, Mitra S, Shamash J, Phillips MM, Luong P, Payne S, Hillman P, Ellis S, Szyszko T, Dancey G, Butcher L, Beck S, Avril NE, Thomson J, Johnston A, Tomsa M, Lawrence C, Schmid P, Crook T, Wu BW, Bomalaski JS, Lemoine N, Sheaff MT, Rudd RM, Fennell D, Hackshaw A. Arginine Deprivation With Pegylated Arginine Deiminase in Patients With Argininosuccinate Synthetase 1-Deficient Malignant Pleural Mesothelioma: A Randomized Clinical Trial. JAMA Oncol. 2017 Jan 1;3(1):58-66.
4. Szlosarek PW, Creelan BC, Sarkodie T, Nolan L, Taylor P, Olevsky O, Grosso F, Cortinovis D, Chitnis M, Roy A, Gilligan D, Kindler H, Papadatos-Pastos D, Ceresoli GL, Mansfield AS, Tsao A, O'Byrne KJ, Nowak AK, Steele J, Sheaff M, Shiu CF, Kuo CL, Johnston A, Bomalaski J, Zauderer MG, Fennell DA; ATOMIC-Meso Study Group. Pegargiminase Plus First-Line Chemotherapy in Patients With Nonepithelioid Pleural Mesothelioma: The ATOMIC-Meso Randomized Clinical Trial. JAMA Oncol. 2024 Apr 1;10(4):475-483.
5. Szlosarek PW, Field G, Pavlyk I, Young M, Allen M, Carpentier J, Shah R, Maskell N, Houghton D, Johnston A, Bomalaski J, Jones L, Sheaff M. Germline HFE mutations predict for durable response to arginine depletion with pegargiminase-based chemotherapy in pleural mesothelioma Free Cancer Res (2026) 86 (8_Supplement): CT139.