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Autophagy inhibition by targeting PIKfyve potentiates response to immune checkpoint blockade in prostate cancer

Abstract

Multi-tyrosine kinase inhibitors (MTKIs) have thus far had limited success in the treatment of castration-resistant prostate cancer (CRPC). Here, we report a phase I–cleared orally bioavailable MTKI, ESK981, with a novel autophagy inhibitory property that decreased tumor growth in diverse preclinical models of CRPC. The antitumor activity of ESK981 was maximized in immunocompetent tumor environments where it upregulated CXCL10 expression through the interferon-γ pathway and promoted functional T cell infiltration, which resulted in enhanced therapeutic response to immune checkpoint blockade. Mechanistically, we identify the lipid kinase PIKfyve as the direct target of ESK981. PIKfyve knockdown recapitulated ESK981’s antitumor activity and enhanced the therapeutic benefit of immune checkpoint blockade. Our study reveals that targeting PIKfyve via ESK981 turns tumors from cold into hot through inhibition of autophagy, which may prime the tumor immune microenvironment in patients with advanced prostate cancer and be an effective treatment strategy alone or in combination with immunotherapies.

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Fig. 1: ESK981 inhibits the growth of prostate cancer cells in vitro and is associated with a vacuolization morphology.
Fig. 2: ESK981 inhibits the growth of diverse preclinical models of prostate cancer in vivo.
Fig. 3: ESK981 induces the accumulation of autophagosomes in prostate cancer cells.
Fig. 4: ESK981 induces the accumulation of lysosomes through inhibition of autophagic flux in prostate cancer cells.
Fig. 5: ESK981 activates an antitumor immune response in immune-competent murine prostate cancer models.
Fig. 6: ESK981 potentiates the effect of anti-PD-1 immunotherapy in immune-competent murine prostate cancer models.
Fig. 7: Identification of lipid kinase PIKfyve as the target of ESK981-induced effects on autophagy and CXCL10 levels.
Fig. 8: Genetic inhibition of Pikfyve potentiates the therapeutic benefit of anti-PD-1 immunotherapy in immune-competent murine models.

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Data availability

Raw RNA-seq data have been deposited at the NCBI Gene Expression Omnibus (GSE174644). Further information and requests for resources and reagents should be directed to the corresponding author. All requests for raw and analyzed data and materials will be reviewed promptly by the corresponding author to verify whether the request is subject to any intellectual property or confidentiality obligations. Any data and materials that can be shared will be released via a material transfer agreement. Source data are provided with this paper.

References

  1. Ferraldeschi, R., Welti, J., Luo, J., Attard, G. & de Bono, J. S. Targeting the androgen receptor pathway in castration-resistant prostate cancer: progresses and prospects. Oncogene 34, 1745–1757 (2015).

    Article  CAS  PubMed  Google Scholar 

  2. Scher, H. I. et al. Increased survival with enzalutamide in prostate cancer after chemotherapy. N. Engl. J. Med. 367, 1187–1197 (2012).

    Article  CAS  PubMed  Google Scholar 

  3. De Bono, J. S. et al. Abiraterone and increased survival in metastatic prostate cancer. N. Engl. J. Med. 364, 1995–2005 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Qiao, Y. et al. Mechanistic support for combined MET and AR blockade in castration-resistant prostate cancer. Neoplasia 18, 1–9 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  5. Ahronian, L. G. & Corcoran, R. B. Strategies for monitoring and combating resistance to combination kinase inhibitors for cancer therapy. Genome Med. 9, 37 (2017).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  6. Smith, D. C. et al. Cabozantinib in patients with advanced prostate cancer: results of a phase II randomized discontinuation trial. J. Clin. Oncol. 31, 412–419 (2013).

    Article  CAS  PubMed  Google Scholar 

  7. Smith, M. et al. Phase III study of cabozantinib in previously treated metastatic castration-resistant prostate cancer: COMET-1. J. Clin. Oncol. 34, 3005–3013 (2016).

    Article  CAS  PubMed  Google Scholar 

  8. Hudkins, R. L. et al. Synthesis and biological profile of the pan-vascular endothelial growth factor receptor/tyrosine kinase with immunoglobulin and epidermal growth factor-like homology domains 2 (VEGF-R/TIE-2) inhibitor 11-(2-methylpropyl)-12,13-dihydro-2-methyl-8-(pyrimidin-2-ylamino)-4H-indazolo[5, 4-a]pyrrolo[3,4-c]carbazol-4-one (CEP-11981): a novel oncology therapeutic agent. J. Med. Chem. 55, 903–913 (2012).

    Article  CAS  PubMed  Google Scholar 

  9. Pili, R., Carducci, M., Brown, P. & Hurwitz, H. An open-label study to determine the maximum tolerated dose of the multitargeted tyrosine kinase inhibitor CEP-11981 in patients with advanced cancer. Invest. New Drugs 32, 1258–1268 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  10. Shisheva, A. PIKfyve: partners, significance, debates and paradoxes. Cell Biol. Int. 32, 591–604 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Gayle, S. et al. Identification of apilimod as a first-in-class PIKfyve kinase inhibitor for treatment of B-cell non-Hodgkin lymphoma. Blood 129, 1768–1778 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Baird, A. M. et al. IL-23R is epigenetically regulated and modulated by chemotherapy in non-small cell lung cancer. Front. Oncol. 3, 162 (2013).

    Article  PubMed  PubMed Central  Google Scholar 

  13. Bonolo De Campos, C. et al. Identification of PIKfyve kinase as a target in multiple myeloma. Haematologica 105, 1641–1649 (2019).

    Article  CAS  Google Scholar 

  14. Levy, J. M. M., Towers, C. G. & Thorburn, A. Targeting autophagy in cancer. Nat. Rev. Cancer 17, 528–542 (2017).

    Article  CAS  PubMed  Google Scholar 

  15. Noman, M. Z. et al. Inhibition of Vps34 reprograms cold into hot inflamed tumors and improves anti-PD-1/PD-L1 immunotherapy. Sci. Adv. 6, eaax7881 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Mgrditchian, T. et al. Targeting autophagy inhibits melanoma growth by enhancing NK cells infiltration in a CCL5-dependent manner. Proc. Natl Acad. Sci. USA 114, E9271–E9279 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Wei, H. et al. Suppression of autophagy by FIP200 deletion inhibits mammary tumorigenesis. Genes Dev. 25, 1510–1527 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Yamamoto, K. et al. Autophagy promotes immune evasion of pancreatic cancer by degrading MHC-I. Nature 581, 100–105 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Beer, T. M. et al. Randomized, double-blind, phase III trial of ipilimumab versus placebo in asymptomatic or minimally symptomatic patients with metastatic chemotherapy-naive castration-resistant prostate cancer. J. Clin. Oncol. 35, 40–47 (2017).

    Article  CAS  PubMed  Google Scholar 

  20. Kwon, E. D. et al. Ipilimumab versus placebo after radiotherapy in patients with metastatic castration-resistant prostate cancer that had progressed after docetaxel chemotherapy (CA184-043): a multicentre, randomised, double-blind, phase 3 trial. Lancet Oncol. 15, 700–712 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Wheeler, D. L., Iida, M. & Dunn, E. F. The role of Src in solid tumors. Oncologist 14, 667–678 (2009).

    Article  CAS  PubMed  Google Scholar 

  22. Nagasawa, J. et al. Novel HER2 selective tyrosine kinase inhibitor, TAK-165, inhibits bladder, kidney and androgen-independent prostate cancer in vitro and in vivo. Int. J. Urol. 13, 587–592 (2006).

    Article  CAS  PubMed  Google Scholar 

  23. Harshman, L. C. et al. An investigator-initiated phase I study of crizotinib in combination with enzalutamide in metastatic castration-resistant prostate cancer (mCRPC) before or after progression on docetaxel. J. Clin. Oncol. 34, e16509 (2016).

    Article  Google Scholar 

  24. Tripathi, A. et al. Dual blockade of c-MET and the androgen receptor in metastatic castration-resistant prostate cancer: a phase I study of concurrent enzalutamide and crizotinib. Clin. Cancer Res. 26, 6122–6131 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Hickman, J. A. et al. Three-dimensional models of cancer for pharmacology and cancer cell biology: capturing tumor complexity in vitro/ex vivo. Biotechnol. J. 9, 1115–1128 (2014).

    Article  CAS  PubMed  Google Scholar 

  26. Harma, V. et al. A comprehensive panel of three-dimensional models for studies of prostate cancer growth, invasion and drug responses. PLoS ONE 5, e10431 (2010).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  27. Robinson, D. et al. Integrative clinical genomics of advanced prostate cancer. Cell 161, 1215–1228 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Yang, Z. J., Chee, C. E., Huang, S. & Sinicrope, F. A. The role of autophagy in cancer: therapeutic implications. Mol. Cancer Ther. 10, 1533–1541 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  29. Klionsky, D. et al. Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition). Autophagy 12, 1–222 2016).

    Article  PubMed  PubMed Central  Google Scholar 

  30. Marx, V. Autophagy: eat thyself, sustain thyself. Nat. Methods 12, 1121–1125 (2015).

    Article  CAS  PubMed  Google Scholar 

  31. Kim, J. & Klionsky, D. J. Autophagy, cytoplasm-to-vacuole targeting pathway, and pexophagy in yeast and mammalian cells. Annu. Rev. Biochem. 69, 303–342 (2000).

    Article  CAS  PubMed  Google Scholar 

  32. Miller, W. T. Tyrosine kinase signaling and the emergence of multicellularity. Biochim. Biophys. Acta 1823, 1053–1057 (2012).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Kaizuka, T. et al. An autophagic flux probe that releases an internal control. Mol. Cell 64, 835–849 (2016).

    Article  CAS  PubMed  Google Scholar 

  34. Poillet-Perez, L. et al. Autophagy maintains tumour growth through circulating arginine. Nature 563, 569–573 (2018).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Kraya, A. A. et al. Identification of secreted proteins that reflect autophagy dynamics within tumor cells. Autophagy 11, 60–74 (2015).

    Article  PubMed  Google Scholar 

  36. Liu, M., Guo, S. & Stiles, J. K. The emerging role of CXCL10 in cancer. Oncol. Lett. 2, 583–589 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  37. Harlin, H. et al. Chemokine expression in melanoma metastases associated with CD8+ T-cell recruitment. Cancer Res. 69, 3077–3085 (2009).

    Article  CAS  PubMed  Google Scholar 

  38. Bronger, H. et al. CXCL9 and CXCL10 predict survival and are regulated by cyclooxygenase inhibition in advanced serous ovarian cancer. Br. J. Cancer 115, 553–563 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  39. Tokunaga, R. et al. CXCL9, CXCL10, CXCL11/CXCR3 axis for immune activation—a target for novel cancer therapy. Cancer Treat. Rev. 63, 40–47 (2018).

    Article  CAS  PubMed  Google Scholar 

  40. Watson, P. A. et al. Context-dependent hormone-refractory progression revealed through characterization of a novel murine prostate cancer cell line. Cancer Res. 65, 11565–11571 (2005).

    Article  CAS  PubMed  Google Scholar 

  41. Serganova, I. et al. Enhancement of PSMA-directed CAR adoptive immunotherapy by PD-1/PD-L1 blockade. Mol. Ther. Oncolytics 4, 41–54 (2017).

    Article  CAS  PubMed  Google Scholar 

  42. Rockenfeller, P. et al. Phosphatidylethanolamine positively regulates autophagy and longevity. Cell Death Differ. 22, 499–508 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Sharma, G. et al. A family of PIKFYVE inhibitors with therapeutic potential against autophagy-dependent cancer cells disrupt multiple events in lysosome homeostasis. Autophagy 15, 1694–1718 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  44. Gayle, S. et al. B-cell non-Hodgkin lymphoma: selective vulnerability to PIKFYVE inhibition. Autophagy 13, 1082–1083 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  45. Efe, J. A., Botelho, R. J. & Emr, S. D. The Fab1 phosphatidylinositol kinase pathway in the regulation of vacuole morphology. Curr. Opin. Cell Biol. 17, 402–408 (2005).

    Article  CAS  PubMed  Google Scholar 

  46. Ciciola, P., Cascetta, P., Bianco, C., Formisano, L. & Bianco, R. Combining immune checkpoint inhibitors with anti-angiogenic agents. J. Clin. Med. 9, 675 (2020).

    Article  CAS  PubMed Central  Google Scholar 

  47. Sbrissa, D., Ikonomov, O. C. & Shisheva, A. PIKfyve, a mammalian ortholog of yeast Fab1p lipid kinase, synthesizes 5-phosphoinositides. Effect of insulin. J. Biol. Chem. 274, 21589–21597 (1999).

    Article  CAS  PubMed  Google Scholar 

  48. Jefferies, H. B. et al. A selective PIKfyve inhibitor blocks PtdIns(3,5)P2 production and disrupts endomembrane transport and retroviral budding. EMBO Rep. 9, 164–170 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  49. Choy, C. H. et al. Lysosome enlargement during inhibition of the lipid kinase PIKfyve proceeds through lysosome coalescence. J. Cell Sci. 131, jcs213587 (2018).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  50. Nguyen, H. G. et al. Targeting autophagy overcomes enzalutamide resistance in castration-resistant prostate cancer cells and improves therapeutic response in a xenograft model. Oncogene 33, 4521–4530 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  51. Yang, S. et al. Pancreatic cancers require autophagy for tumor growth. Genes Dev. 25, 717–729 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  52. Saleem, A. et al. Effect of dual inhibition of apoptosis and autophagy in prostate cancer. Prostate 72, 1374–1381 (2012).

    Article  CAS  PubMed  Google Scholar 

  53. Santanam, U. et al. Atg7 cooperates with Pten loss to drive prostate cancer tumor growth. Genes Dev. 30, 399–407 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  54. Poillet-Perez, L. et al. Autophagy promotes growth of tumors with high mutational burden by inhibiting a T-cell immune response. Nat. Cancer 1, 923–934 (2020).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  55. Antonarakis, E. S. et al. Pembrolizumab for treatment-refractory metastatic castration-resistant prostate cancer: multicohort, open-label phase II KEYNOTE-199 study. J. Clin. Oncol. 38, 395–405 (2020).

    Article  CAS  PubMed  Google Scholar 

  56. Abida, W. et al. Analysis of the prevalence of microsatellite instability in prostate cancer and response to immune checkpoint blockade. JAMA Oncol. 5, 471–478 (2019).

    Article  PubMed  Google Scholar 

  57. Antonarakis, E. S. et al. Clinical features and therapeutic outcomes in men with advanced prostate cancer and DNA mismatch repair gene mutations. Eur. Urol. 75, 378–382 (2019).

    Article  CAS  PubMed  Google Scholar 

  58. Antonarakis, E. S. et al. CDK12-altered prostate cancer: clinical features and therapeutic outcomes to standard systemic therapies, poly (ADP-ribose) polymerase inhibitors, and PD-1 inhibitors. JCO Precis. Oncol 4, 370–381 (2020).

    Article  PubMed  Google Scholar 

  59. Wu, Y. M. et al. Inactivation of CDK12 delineates a distinct immunogenic class of advanced prostate cancer. Cell 173, 1770–1782.e14 (2018).

    Article  CAS  PubMed  Google Scholar 

  60. Chen, C. D. et al. Molecular determinants of resistance to antiandrogen therapy. Nat. Med. 10, 33–39 (2004).

    Article  PubMed  CAS  Google Scholar 

  61. Wang, L. et al. VSTM2A overexpression is a sensitive and specific biomarker for mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney. Am. J. Surg. Pathol. 42, 1571–1584 (2018).

    Article  PubMed  PubMed Central  Google Scholar 

  62. Bernard, A. et al. Rph1/KDM4 mediates nutrient-limitation signaling that leads to the transcriptional induction of autophagy. Curr. Biol. 25, 546–555 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  63. Martinez Molina, D. et al. Monitoring drug target engagement in cells and tissues using the cellular thermal shift assay. Science 341, 84–87 (2013).

    Article  PubMed  CAS  Google Scholar 

  64. Jafari, R. et al. The cellular thermal shift assay for evaluating drug target interactions in cells. Nat. Protoc. 9, 2100–2122 (2014).

    Article  CAS  PubMed  Google Scholar 

  65. Palanisamy, N. et al. The MD Anderson prostate cancer patient-derived xenograft series (MDA PCa PDX) captures the molecular landscape of prostate cancer and facilitates marker-driven therapy development. Clin. Cancer Res. 26, 4933–4946 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  66. Yu, J. L. et al. Liver metastasis restrains immunotherapy efficacy via macrophage-mediated T cell elimination. Nat. Med. 27, 152–164 (2021).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  67. Sanjana, N. E., Shalem, O. & Zhang, F. Improved vectors and genome-wide libraries for CRISPR screening. Nat. Methods 11, 783–784 (2014).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  68. Dobin, A. et al. STAR: ultrafast universal RNA-seq aligner. Bioinformatics 29, 15–21 (2013).

    Article  CAS  PubMed  Google Scholar 

  69. Love, M. I., Huber, W. & Anders, S. Moderated estimation of fold change and dispersion for RNA-seq data with DESeq2. Genome Biol. 15, 550 (2014).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  70. Robinson, M. D., McCarthy, D. J. & Smyth, G. K. edgeR: a Bioconductor package for differential expression analysis of digital gene expression data. Bioinformatics 26, 139–140 (2010).

    Article  CAS  PubMed  Google Scholar 

  71. Afshinnia, F. et al. Lipidomic signature of progression of chronic kidney disease in the chronic renal insufficiency cohort. Kidney Int. Rep. 1, 256–268 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  72. Bligh, E. G. & Dyer, W. J. A rapid method of total lipid extraction and purification. Can. J. Biochem. Physiol. 37, 911–917 (1959).

    Article  CAS  PubMed  Google Scholar 

  73. Cajka, T. & Fiehn, O. LC-MS-based lipidomics and automated identification of lipids using the LipidBlast in-silico MS/MS library. Methods Mol. Biol. 1609, 149–170 (2017).

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

We thank M. Trierweiler and S. Zelenka-Wang for histological sample processing and IHC, as well as undergraduate student K. Johnson for technical assistance. This work was supported by a Prostate Cancer Foundation Challenge Award, NCI Prostate SPORE Grant P50CA186786, Department of Defense PC130151P1 (to N.M.N. and A.M.C.) and NIH grant GM131919 (to D.J.K.). A.M.C. is an NCI Outstanding Investigator (R35CA231996), Howard Hughes Medical Institute Investigator, A. Alfred Taubman Scholar and American Cancer Society Professor. Y.Q. and J.C.T. are supported by Prostate Cancer Foundation Young Investigator awards. L.X. is supported by a Department of Defense Postdoctoral Award (W81XWH-16-1-0195). E.-L.E. was supported by the Academy of Finland.

Author information

Authors and Affiliations

Authors

Contributions

Y.Q. and A.M.C. participated in the planning, initiation and overall analysis of data, as well as writing, reviewing and editing of the manuscript. Y.Q., S.A.S., A.D.D., N.B.H., P.D. and S.M. performed the in vitro and in vivo experiments. J.C.T., J.E.C., K.J. and A.X. participated in the in vivo experiments. Y.Q., T.R. and T.S. participated in the lipidomics experimental design and data analysis. Z.W. and K.D. participated in execution of the chemical synthesis of ESK981. L.W., X.-M.W. and J.S. performed the histological sample preparation, staining and interpretation of RNA ISH results. L.X. helped with the CRISPR Atg5 knockout design. X.W. assisted with the ELISA experiments. X.C., F.S., R.W. and J.N.V. performed the RNA-seq library preparation, sequencing and data analysis. J.Y., I.K. and J.E.C. participated in the flow cytometry analysis. A.B. and D.J.K. participated in the yeast experiments and data interpretation. E.-L.E. performed the electron microscopy analysis. E.-L.E. and D.J.K. participated in the autophagy data interpretation. N.M.N. provided the PDX models. S.J.E. participated in writing and preparation of the manuscript. W.Z. participated in the immune checkpoint blockade experimental design and data interpretation. E.F.-S., E.I.H. and A.M.C. provided project oversight for clinical trial design and review based on the interpretation of the preclinical data.

Corresponding author

Correspondence to Arul M. Chinnaiyan.

Ethics declarations

Competing interests

The University of Michigan has filed a disclosure on the findings based on this study. A.M.C. and Y.Q. are named as co-inventors on the disclosure. Esanik Therapeutics licensed ESK981 from Teva Pharmaceuticals. A.M.C. is a co-founder of Esanik Therapeutics and serves on its scientific advisory board. Neither Esanik Therapeutics nor Teva Pharmaceuticals was involved in the design or approval of this study, nor was this study funded by them. The remaining authors declare no competing interests.

Additional information

Peer review information Nature Cancer thanks Cory Abate-Shen, Thorbald van Hall and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Extended data

Extended Data Fig. 1 ESK981 blocks cell growth, induces cell cycle arrest, and decreases cellular invasion.

a-b, Representative crystal violet staining for a long-term survival assay of a panel of prostate cell lines at various concentrations of ESK981, crizotinib, or cabozantinib. c, Cell cycle analysis was measured after 72 hours of increasing concentrations of ESK981 treatment in indicated prostate cancer cell lines. Ctrl, control. d, Cell cycle analysis of VCaP cells that were treated with the indicated compounds for 72 hours. Cabo, cabozantinib; Crizo, crizotinib; Enza, enzalutamide; ESK, ESK981. e, Matrigel invasion assay of various prostate cancer cell lines that were treated with the indicated concentrations of ESK981. The percentage invasion was quantified with a fluorescent plate reader. Data were analyzed by two-tailed unpaired t test from three independent experiments and presented as mean ± SEM. P-value indicated.

Source data

Extended Data Fig. 2 ESK981 inhibits the growth of diverse preclinical models of prostate cancer in vivo.

a, Schematic illustration of the VCaP CRPC mouse xenograft experimental design. To generate castration-resistant VCaP, parental VCaP cells were injected subcutaneously into both flanks of intact male mice. When average VCaP tumors reached 200 mm3, mice were surgically castrated and VCaP tumors regressed due to loss of androgen. Castration-resistant VCaP tumors developed as VCaP tumors grew back to the size of pre-castration. Castration-resistant VCaP tumors were then randomized into three groups and treated with vehicle, 30 mg/kg, or 60 mg/kg ESK981 p.o., oral gavage. b, Representative IHC images for proliferation marker Ki67 are shown after treatment with the indicated drugs for five days in VCaP tumors (left). Quantification of positive Ki67 percentage is shown on the right (right). Data were analyzed by two-tailed unpaired t test and presented as mean ± SEM. N = 4 tumors per group. P-value indicated. c, Representative individual tumors from vehicle and ESK981 groups in AR+ and ERG+ prostate PDX MDA-PCa-146-12 (left). Representative IHC showing Ki67 staining for vehicle and 30 mg/kg ESK981 groups of MDA-PCa-146-12 tumors (right) from three independent experiments. d, Representative individual tumors from vehicle and ESK981 groups of DU145 tumors (left). Representative IHC showing Ki67 staining for the vehicle and 30 mg/kg ESK981 groups of DU145 tumors (right) from three independent experiments.

Source data

Extended Data Fig. 3 Renal function, liver function, and histopathological evaluation of ESK981-treated xenografts.

a, Castration-resistant VCaP tumors were established according to Extended Data Fig. 2a. Tumor-bearing mice were divided into vehicle and ESK981 50 mg/kg groups, and tumor volumes were monitored twice per week for six weeks. Data were analyzed by two-tailed unpaired t test and presented as mean ± SEM at day 25. N = number of tumors and P-value indicated. b, The percent body weights of VCaP tumor-bearing mice were monitored daily throughout this study. Data were presented as mean ± SEM. N = number of mice. c, The weight of VCaP tumors from vehicle (n = 18 tumors) and ESK981 50 mg/kg (n = 10 tumors) were measured at the end of this study. Data were analyzed by two-tailed unpaired t test and presented as mean ± SEM. P-value indicated. d, Blood chemistry was evaluated for renal and liver functions in non-tumor-bearing and VCaP tumor-bearing mice in vehicle and 50 mg/kg ESK981 treatment groups. e, Representative histological sections showing H&E staining for various organs taken from vehicle- or ESK981-treated mice from three independent experiments. f, Representative histological sections showing H&E staining for tumors taken from vehicle- or ESK981-treated mice from three independent experiments.

Source data

Extended Data Fig. 4 ESK981 robustly induces autophagosome levels and is dependent on ATG5 for its effects.

a, DU145 cells with the indicated drug treatment for 24 hours. Autophagosome induction activity was visualized by CYTO-ID® assay from three independent experiments. Rapa, rapamycin. b, VCaP cells were treated with 300 nM ESK981 for the indicated time points, and LC3 protein levels were assessed by western blot from three independent experiments. c, VCaP cells were treated with ESK981 (ESK), crizotinib (Crizo), and cabozantinib (Cabo) at the indicated concentrations. Protein levels of LC3 were examined after 24 hours of treatment from three independent experiments. d, Protein levels of Atg8 in yeast prd5Δ cells after ESK981 (ESK) or cabozantinib (Cabo) treatment under nitrogen deprivation conditions. NT, no treatment. Data were analyzed by two-tailed unpaired t test from four independent experiments and presented as mean ± SEM. P value indicated. e, Protein levels of indicated protein post various siRNA knockdown in VCaP and LNCaP cells with or without 300 nM ESK981 or 1 µM sunitinib treatment for 24 hours from three independent experiments.

Source data

Extended Data Fig. 5 ESK981 upregulates CXCL10 expression in human prostate cancer cells and inhibits autophagy in murine Myc-CaP prostate cancer cells.

(a) CXCL10 protein levels measured by ELISA in conditioned media from VCaP cells treated with ESK981 or various autophagy inducers for 24 hours. Data were analyzed by two-tailed unpaired t test from three independent experiments and presented as mean ± SEM. P-value indicated. (b) CXCL10 mRNA levels measured by quantitative PCR (qPCR) in VCaP, PC3, and DU145 cells with the indicated treatment for 24 hours. IFNγ, interferon gamma. Data were analyzed by two-tailed unpaired t test from three independent experiments and presented as mean ± SEM. P-value indicated. (c) IC50 of ESK981, crizotinib, and cabozantinib determined in Myc-CaP cells. (d) Protein levels of LC3 after 50 nM, 100 nM, and 300 nM ESK981 treatment for 24 hours in Myc-CaP cells from three independent experiments. (e) Ratio of GFP/RFP signal in Myc-CaP GFP-LC3-RFP-LC3∆G stable expressing cells with the indicated treatment for 24 hours. Data were analyzed by two-tailed unpaired t test from four independent experiments and presented as mean ± SEM. P-value indicated.

Source data

Extended Data Fig. 6 Atg5 deletion blocks ESK981-induced vacuolization and CXCL10-mediated immune response.

(a) Myc-CaP wild-type (WT) and Atg5 knockout (Atg5 KO) cells were treated with increasing concentrations of ESK981 for 24 hours. Atg5 and LC3 levels were assessed by western blot from three independent experiments. GAPDH served as a loading control. (b) Representative morphology of vacuolization in Myc-CaP wild-type (WT) and Atg5 knockout (Atg5 KO) cells after treatment with control or 100 nM ESK981 for 24 hours from three independent experiments. (c) Autophagosome content of Myc-CaP WT and Atg5 KO cells were measured by CYTO-ID® assay after being treated with increasing concentrations of ESK981 for 24 hours. Data were analyzed by two-tailed unpaired t test from three independent experiments and presented as mean ± SEM. P-value indicated. (d) Mouse cytokine array using Myc-CaP WT and Atg5 KO cell supernatant after treatment with 10 ng/ml mouse interferon gamma (mIFNγ) or mIFNγ + 100 nM ESK981 for 24 hours. Differential expression candidate dots are highlighted by boxes. (e) Mouse CXCL10 protein levels were measured by ELISA in Myc-CaP WT and Atg5 KO conditioned medium with the indicated treatment for 24 hours. Data were analyzed by two-tailed unpaired t test from three independent experiments and presented as mean ± SEM. P-value indicated. (f) mRNA levels of Cxcl10 and Cxcl9 were measured by qPCR in Myc-CaP WT and Atg5 KO cells with 50 nM or 100 nM ESK981 and 10 ng/ml mIFNγ treatment for 24 hours. Data were analyzed by two-tailed unpaired t test from three independent experiments and presented as mean ± SEM. P-value indicated.

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Extended Data Fig. 7 Transcriptomic analysis of Myc-CaP tumors treated with ESK981 in combination with anti-PD-1 immunotherapy in FVB mice.

(a) Principal Component Analysis (PCA) of individual Myc-CaP tumors from indicated treatment groups based on variance-stabilizing transformation (vst) of read-count data. The vehicle and ESK981+anti-PD-1 combination groups form a relatively distinct cluster based on the first two principal components. (b) Volcano plot of differential gene expression analysis for groups treated with ESK981+anti-PD-1 versus vehicle. The horizontal dashed line corresponds to the FDR = 0.05. The vertical dashed lines correspond to log2FC >= 1 (up-regulation) or log2FC <= -1 (down-regulation). (c) Mouse Gene Set Enrichment Analysis (GSEA) with biological process gene ontology for groups treated with ESK981+anti-PD-1 versus vehicle. Top 10 gene sets are ordered by normalized enrichment score (NES). The top enriched categories are relevant to immune responses and inflammation. (d) Heatmap representation of top differentially expressed genes in groups treated with ESK981+anti-PD-1 versus vehicle (FDR <= 0.01, up or down-regulated by at least 2-fold). (e) Fragments per kilobase of exon model per million reads mapped (FPKM) of indicated targets from individual Myc-CaP tumors treated with vehicle (n = 10 tumors), ESK981 (n = 8 tumors), anti-PD-1 (n = 7 tumors), or ESK981+anti-PD-1 (n = 8 tumors). Data were analyzed by two-tailed unpaired t test and presented as mean ± SEM. P-value indicated.

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Extended Data Fig. 8 ESK981 induces autophagosome formation and upregulates Cxcl10 expression in various murine cancer cell lines.

a, IC50 from cell viability assays of ESK981 in murine cancer cells of lung (Ae17, LLC), melanoma (B16F10), ovarian (ID8), pancreas (PAN02), renal (Renca), prostate (TRAMP-C2), and breast (4T1) lineages. Data were plotted as mean ± SEM from three independent experiments. b, Autophagosome content measured by CYTO-ID in indicated cell lines treated with control (Ctrl) or 300 nM ESK981 for 24 hours. Data were analyzed by two-tailed unpaired t test from four independent experiments and presented as mean ± SEM. P-value indicated. c, mRNA level of Cxcl10 in indicated cell lines treated with 10 ng/ml mIFNγ or mIFNγ plus 300 nM ESK981 for 24 hours. Data were analyzed by two-tailed unpaired t test from three (PAN02, Ae17) or four (ID8, B16F10, Renca, 4T1, TRAMP-C2, LLC) independent experiments and presented as mean ± SEM. P-value indicated.

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Extended Data Fig. 9 ESK981 sensitizes the murine breast cancer 4T1 model to anti-PD-1 immunotherapy.

a, Bioluminescent signaling images showing dorsal and ventral views of individual 4T1 tumor-bearing mice from indicated treatment groups. b, Bioluminescent quantification of total tumor burden from individual mice treated with vehicle (n = 5 mice), anti-PD-1 (n = 4 mice), ESK981 15 mg/kg (n = 5 mice), ESK981+anti-PD-1 (n = 5 mice). Data were analyzed by two-tailed unpaired t test and presented as mean ± SEM. P-value indicated. c, Overall survival of 4T1-bearing mice treated with either anti-PD-1 (n = 15 mice) or ESK981 and anti-PD-1 combination (n = 15 mice).

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Extended Data Fig. 10 PIKfyve mediates a cellular vacuolization morphology in human prostate cancer cells and murine cancer cells, and Pikfyve loss induces accumulation of autophagosomes in various murine cancer cells.

a, Morphology of DU145 and PC3 cells after siNC, siPIKFYVE, siPIP5K1C, or siPIK3CA transfection from three independent experiments. b, mRNA levels of PIKFYVE, PIP5K1C, and PIK3CA were measured by qPCR after siRNA knockdown of indicated targets in DU145 and PC3 cells. Data were analyzed by two-tailed unpaired t test and presented as mean ± SEM from three independent experiments. P-value indicated. c, Morphological changes of TRAMP-C2, ID8, and Ae17 cells after siNC or siPikfyve transfection from three independent experiments. d, Autophagosome induction activity measured with CYTO-ID® assay in TRAMP-C2, ID8, and Ae17 cells after siRNA knockdown of Pikfyve. Data were analyzed by two-tailed unpaired t test and presented as mean ± SEM from four (TRAMP-C2 and ID8) and six (Ae17) independent experiments. P-value indicated.

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Qiao, Y., Choi, J.E., Tien, J.C. et al. Autophagy inhibition by targeting PIKfyve potentiates response to immune checkpoint blockade in prostate cancer. Nat Cancer 2, 978–993 (2021). https://doi.org/10.1038/s43018-021-00237-1

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