Crosstalk between hypoxia-sensing ULK1/2 and YAP-driven glycolysis fuels pancreatic ductal adenocarcinoma development

Abstract

Autophagy and glycolysis are two catabolic processes that manipulate pancreatic ductal adenocarcinoma (PDAC) development in response to hypoxia sensing, yet the underlying mechanism of how they are interlinked remain elusive. Methods: The functional roles of Unc-51 like kinase 1 and 2 (ULK1/2) in pyruvate kinase M2 (PKM2) transcription and glycolysis under hypoxia were assessed by chromatin immunoprecipitation, luciferase reporter, glucose consumption and lactate production assay. Co-immunoprecipitation, cellular ubiquitination, His-pulldown, in vitro protein kinase assay, immunofluorescence, immunohistochemistry, CRISPR technology, in silico studies were adopted to determine the molecular mechanism. Correlation analyses were performed in KPC ( Pdx1 -Cre; LSL-Kras G12D/+ ; Trp53 fl/+ ) mice and clinical samples from PDAC patients. Therapeutic potential of ULK1/2 inhibitor and 2-deoxyglucose (2-DG) or 3-bromopyruvate (3-BP) was evaluated in cell-derived xenograft (CDX) and the patient-derived xenograft (PDX) models of nude mice. Results: ULK1/2, but not ULK3, augments hypoxic glycolysis in PDAC cells mediated by PKM2 independent of BCL2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3). Mechanistically, hypoxia stimulates ULK1 to translocate into nucleus, where it interacts with and phosphorylates yes-associated protein (YAP) at Ser227, resulting in YAP stabilization through blockade of ubiquitin-proteasome system (UPS), which in turn facilitates PKM2 transcription, glycolysis, cell proliferation in vitro as well as PDAC growth in mice. ULK1/2 is positively correlated with YAP and PKM2 in tumor tissues from KPC mice and clinical samples from PDAC patients. Pharmacological deactivation of ULK1/2 potentiates the antineoplastic efficacy of 2-DG and 3-BP in CDX and PDX models. Conclusion: Our findings underscore the Ser227 autophosphorylation-dependent nuclear YAP stabilization as a central node that couples ULK1/2-initiated autophagy to hypoxic glycolysis during PDAC development and propose that targeting ULK1/2 combined with 2-DG or 3-BP might be a feasible therapeutic strategy against PDAC.

Obstructive sleep apnea predicts pathologic response to neoadjuvant therapy in resected pancreatic ductal adenocarcinoma

“…Large amounts of hypoxia mechanisms on promoting PDAC cell progression have been illuminated, containing crosstalk between hypoxiasensing ULK1/2 and YAP-driven glycolysis, HIF-1α/Notch signaling pathway and noncoding RNA-related signaling, etc. [7][8][9] According to these studies, OSA may contribute to the aggressive phenotype of PDAC.…”

Tripartite motif containing 69 elicits ERK2-dependent EYA4 turnover to impart pancreatic tumorigenesis

“…All animal experiments were conducted with the approval of the Institutional Animal Care and Use Committee (IACUC) guidance of Huazhong University of Science and Technology (HUST). The KPC (Pdx1-Cre; LSL-Kras G12D/+ ; Trp53 fl/+ ) mice which could spontaneously develop pancreas adenocarcinoma were generated by crossing the Pdx1-Cre mice with the LSL-Kras G12D/+ ;Trp53 fl/+ (KP) mice as in previous publication [18]. All mice were bred in a specific-pathogen-free environment, with the temperature maintained at 24 °C and sterile conditions at the Animal Experiment Center of HUST.…”

Autophagy and beyond: Unraveling the complexity of UNC-51-like kinase 1 (ULK1) from biological functions to therapeutic implications

“…S100A10, a member of the S100 protein family, was found to directly interact with ULK1 and further stimulate the localization of ULK1 to ER-mitochondria contact sites 184 . Interestingly, hypoxia can stimulate ULK1 to translocate into nucleus, further regulating YAP-driven glycolysis in pancreatic ductal adenocarcinoma (PDAC) 185 . Additionally, some regulators enhance the interaction of ULK1 with its partner to affect ULK1 and autophagy.…”

“… Name Classification Positive regulation/ Negative regulation Mechanism Ref. 1 Copper Metal ion Positive regulation Enhancing ULK1 kinase activity by directly interaction 181 2 GABARAP/GABARAPL1 Protein Positive regulation GABARAP/GABARAPL1 positively regulate starvation-induced ULK1 activation and are important for maintaining the expression or stability of the ULK1 complex proteins 182 3 LC3B/C Protein Negative regulation LC3B/C might negatively regulate ULK1 by reducing the expression or stability of GABARAPs 182 4 TFG Protein / Binding LC3C to regulate ULK1 localization and autophagosome formation 183 5 S100A10 Protein Positive regulation S100A10 regulates ULK1 translocation to ER-mitochondria contact sites in response to IFN-stimulation 184 6 Hypoxia Cellular microenvironment Positive regulation Hypoxia stimulates ULK1 to translocate into nucleus 185 7 c9orf72 Protein Positive regulation C9orf72 regulates ULK1 expression via regulation of the ULK1 complex 186 8 NDP52 Protein Positive regulation NDP52 recruits the ULK1 complex and triggers membrane recruitment 187 9 SMCR8 GTPases Negative regulation SMCR8 regulates ULK1 kinase activity, ULK1 gene and protein expression 188 10 RAB2 GTPases Positive regulation RAB2 facilitates the recruitment of ULK1 complex...…”

“…And down-regulating ULK1 could repress tumorigenic activities of pancreatic cancer cells by regulating autophagy-mediated mitochondrial metabolism 209 . In the hypoxic microenvironment of PDAC, ULK1-triggered autophagy and glycolysis act as a niche for malignant growth and drug resistance by stabilizing previously unrecognized crosstalk between nuclear YAPs during PDAC development 185 . Notably, PVT1/miR-20a-5p/ULK1/autophagy pathway 74 , MDH1–ULK1 pathway 196 , and LKB1–AMPK–ULK1 signaling axis 210 , may be novel targets for developing therapeutic strategies for PDA by leading to autophagy induction.…”