Introduction: Inducible co-stimulator (ICOS), an important co-stimulatory receptor on effector T cells (Teffs), may also contribute to tumor growth due to its high expression on regulatory T cells (Tregs). This study explored the clinical significance of ICOS-expressing Tregs in hepatocellular carcinoma (HCC). Methods: Tumor tissues from HCC patients who received curative hepatectomy were obtained at a referral center. Dual immunohistochemistry was performed to evaluate the expression of ICOS and Foxp3. The cell densities and proximities between stained cells in regions of interest were measured by digital pathology and the associations with clinical outcome were analyzed. Results: A total of 142 patients (male:female = 112: 30, median age of 61.0 years) were enrolled. Among them, 87 (61.3%) had chronic hepatitis B virus infection and 33 (23.2%) had chronic hepatitis C infection. Low α-fetoprotein level (<20 ng/mL) and early-stage were significantly associated with improved overall survival (OS). The density of ICOS+Foxp3+ cells and the ratio of ICOS+Foxp3+/total Foxp3+ cells were significantly higher (p < 0.001) in the tumor center than in the peritumor area. Patients with a high density of ICOS+Foxp3+ cells or a high ratio of ICOS+Foxp3+/total Foxp3+ cells in the tumor center trended to have a shorter OS. A shorter distance between ICOS+Foxp3+ cells and ICOS+Foxp3− cells (likely Teffs) in the tumor center was significantly associated with a shorter OS (p = 0.030), suggesting active immunosuppression of ICOS+ Tregs on ICOS+ Teffs. Conclusion: An increased abundance of ICOS+ Tregs in the tumor center in comparison to the peritumor area indicates a strong immunosuppressive tumor microenvironment of HCC. A high proportion of ICOS+Foxp3+ cells and a shorter distance between ICOS+ Tregs and other ICOS+ cells were associated with a poor OS, suggesting that depleting ICOS+ Tregs might provide clinical benefit for patients with HCC.

Keywords:
Liver cancer, Foxp3, Co-stimulatory receptor, Tumor microenvironment, Immunotherapy, Immune checkpoint
1.
Llovet JM, Ricci S, Mazzaferro V, Hilgard P, Gane E, Blanc JF, et al. Sorafenib in advanced hepatocellular carcinoma.
N Engl J Med
. 2008 Jul;359(4):378–90.
2.
Cheng AL, Kang YK, Chen Z, Tsao CJ, Qin S, Kim JS, et al. Efficacy and safety of sorafenib in patients in the Asia-Pacific region with advanced hepatocellular carcinoma: a phase III randomised, double-blind, placebo-controlled trial.
Lancet Oncol
. 2009 Jan;10(1):25–34.
3.
Kudo M, Finn RS, Qin S, Han KH, Ikeda K, Piscaglia F, et al. Lenvatinib versus sorafenib in first-line treatment of patients with unresectable hepatocellular carcinoma: a randomised phase 3 non-inferiority trial.
Lancet
. 2018 Mar;391(10126):1163–73.
4.
Bruix J, Qin S, Merle P, Granito A, Huang YH, Bodoky G, et al. Regorafenib for patients with hepatocellular carcinoma who progressed on sorafenib treatment (RESORCE): a randomised, double-blind, placebo-controlled, phase 3 trial.
Lancet
. 2017 Jan;389(10064):56–66.
5.
Abou-Alfa GK, Meyer T, Cheng AL, El-Khoueiry AB, Rimassa L, Ryoo BY, et al. Cabozantinib in patients with advanced and progressing hepatocellular carcinoma.
N Engl J Med
. 2018 Jul;379(1):54–63.
6.
Zhu AX, Kang YK, Yen CJ, Finn RS, Galle PR, Llovet JM, et al. Ramucirumab after sorafenib in patients with advanced hepatocellular carcinoma and increased α-fetoprotein concentrations (REACH-2): a randomised, double-blind, placebo-controlled, phase 3 trial.
Lancet Oncol
. 2019 Feb;20(2):282–96.
7.
El-Khoueiry AB, Sangro B, Yau T, Crocenzi TS, Kudo M, Hsu C, et al. Nivolumab in patients with advanced hepatocellular carcinoma (CheckMate 040): an open-label, non-comparative, phase 1/2 dose escalation and expansion trial.
Lancet
. 2017 Jun;389(10088):2492–502.
8.
Zhu AX, Finn RS, Edeline J, Cattan S, Ogasawara S, Palmer D, et al. Pembrolizumab in patients with advanced hepatocellular carcinoma previously treated with sorafenib (KEYNOTE-224): a non-randomised, open-label phase 2 trial.
Lancet Oncol
. 2018 Jul;19(7):940–52.
9.
Finn RS, Qin S, Ikeda M, Galle PR, Ducreux M, Kim TY, et al. Atezolizumab plus bevacizumab in unresectable hepatocellular carcinoma.
N Engl J Med
. 2020 May;382(20):1894–905.
10.
Yau T, Kang YK, Kim TY, El-Khoueiry AB, Santoro A, Sangro B, et al. Efficacy and safety of nivolumab plus ipilimumab in patients with advanced hepatocellular carcinoma previously treated with sorafenib: the CheckMate 040 randomized clinical trial.
JAMA Oncol
. 2020 Nov;6(11):e204564.
11.
Kelley R, Sangro B, Harris W, Ikeda M, Okusaka T, Kang Y, et al. Safety, efficacy, and pharmacodynamics of tremelimumab plus durvalumab for patients with unresectable hepatocellular carcinoma: randomized expansion of a phase I/II study.
J Clin Oncol
. 2021 Sep;39(27):2991–3001.
12.
Mayes PA, Hance KW, Hoos A. The promise and challenges of immune agonist antibody development in cancer.
Nat Rev Drug Discov
. 2018 Jul;17(7):509–27.
13.
Mellman I, Coukos G, Dranoff G. Cancer immunotherapy comes of age.
Nature
. 2011 Dec;480(7378):480–9.
14.
Yap TA, Burris HA, Kummar S, Falchook GS, Pachynski RK, LoRusso P, et al. ICONIC: biologic and clinical activity of first in class ICOS agonist antibody JTX-2011 +/− nivolumab (nivo) in patients (pts) with advanced cancers.
J Clin Oncol
. 2018 Jun;36(15_Suppl l):3000.
15.
Hansen A, Bauer TM, Moreno V, Maio M, Groenland S, Martin-Liberal J, et al. First in human study with GSK3359609 [GSK609], inducible T cell co-stimulator (ICOS) receptor agonist in patients [Pts] with advanced, solid tumors: preliminary results from INDUCE-1.
Ann Oncol
. 2018 Oct;29(8):VIII404.
16.
Quaratino S, Sainson R, Thotakura A, Henderson SJ, Pryke K, Newton A, et al. A first-in-human study of KY1044, a fully human anti-ICOS IgG1 antibody as monotherapy and in combination with atezolizumab in patients with selected advanced malignancies.
J Clin Oncol
. 2019 May;37(15_Suppl l):TPS2644.
17.
Sainson RCA, Thotakura AK, Kosmac M, Borhis G, Parveen N, Kimber R, et al. An antibody targeting ICOS increases intratumoral cytotoxic to regulatory T-cell ratio and induces tumor regression.
Cancer Immunol Res
. 2020 Dec;8(12):1568–82.
18.
Strauss L, Bergmann C, Szczepanski MJ, Lang S, Kirkwood JM, Whiteside TL. Expression of ICOS on human melanoma-infiltrating CD4+CD25highFoxp3+ T regulatory cells: implications and impact on tumor-mediated immune suppression.
J Immunol
. 2008 Mar;180(5):2967–80.
19.
Tu JF, Ding YH, Ying XH, Wu FZ, Zhou XM, Zhang DK, et al. Regulatory T cells, especially ICOS+ FOXP3+ regulatory T cells, are increased in the hepatocellular carcinoma microenvironment and predict reduced survival.
Sci Rep
. 2016 Oct;6:35056.
20.
Shao YY, Chen PJ, Lin ZZ, Huang CC, Ding YH, Lee YH, et al. Impact of baseline hepatitis B viral DNA levels on survival of patients with advanced hepatocellular carcinoma.
Anticancer Res
. 2011 Nov;31(11):4007–11.
21.
Zheng J, Chan PL, Liu Y, Qin G, Xiang Z, Lam KT, et al. ICOS regulates the generation and function of human CD4+ Treg in a CTLA-4 dependent manner.
PLoS One
. 2013 Dec;8(12):e82203.
22.
Busse M, Krech M, Meyer-Bahlburg A, Hennig C, Hansen G. ICOS mediates the generation and function of CD4+CD25+Foxp3+ regulatory T cells conveying respiratory tolerance.
J Immunol
. 2012 Aug;189(4):1975–82.
23.
Kornete M, Sgouroudis E, Piccirillo CA. ICOS-dependent homeostasis and function of Foxp3+ regulatory T cells in islets of nonobese diabetic mice.
J Immunol
. 2012 Feb;188(3):1064–74.
24.
Redpath SA, van der Werf N, Cervera AM, MacDonald AS, Gray D, Maizels RM, et al. ICOS controls Foxp3(+) regulatory T-cell expansion, maintenance and IL-10 production during helminth infection.
Eur J Immunol
. 2013 Mar;43(3):705–15.
25.
Nagase H, Takeoka T, Urakawa S, Morimoto-Okazawa A, Kawashima A, Iwahori K, et al. ICOS+ Foxp3+ TILs in gastric cancer are prognostic markers and effector regulatory T cells associated with Helicobacter pylori.
Int J Cancer
. 2017 Feb;140(3):686–95.
26.
Liu X, Yu H, Yan C, Mei Y, Lin C, Hong Y, et al. Plasmacytoid dendritic cells and ICOS+ regulatory T cells predict poor prognosis in gastric cancer: a pilot study.
J Cancer
. 2019 Oct;10(26):6711–5.
27.
Conrad C, Gregorio J, Wang YH, Ito T, Meller S, Hanabuchi S, et al. Plasmacytoid dendritic cells promote immunosuppression in ovarian cancer via ICOS costimulation of Foxp3(+) T-regulatory cells.
Cancer Res
. 2012 Oct;72(20):5240–9.
28.
Yu H, Huang X, Liu X, Jin H, Zhang G, Zhang Q, et al. Regulatory T cells and plasmacytoid dendritic cells contribute to the immune escape of papillary thyroid cancer coexisting with multinodular non-toxic goiter.
Endocrine
. 2013 Aug;44(1):172–81.
29.
Gao Q, Qiu SJ, Fan J, Zhou J, Wang XY, Xiao YS, et al. Intratumoral balance of regulatory and cytotoxic T cells is associated with prognosis of hepatocellular carcinoma after resection.
J Clin Oncol
. 2007 Jun;25(18):2586–93.
30.
Pfister D, Núñez NG, Pinyol R, Govaere O, Pinter M, Szydlowska M, et al. NASH limits anti-tumour surveillance in immunotherapy-treated HCC.
Nature
. 2021 Apr;592(7854):450–6.
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