Elsevier

European Journal of Cancer

Volume 60, June 2016, Pages 125-135
European Journal of Cancer

Original Research
High co-expression of PD-L1 and HIF-1α correlates with tumour necrosis in pulmonary pleomorphic carcinoma

https://doi.org/10.1016/j.ejca.2016.03.012Get rights and content

Highlights

  • High PD-L1 and HIF-1α co-expression was observed in pulmonary pleomorphic carcinoma.

  • This feature is common in surrounding areas of tumour necrosis.

  • The aggressive behaviour could be partially related to PD-L1–mediated immune escape.

Abstract

Background

Pulmonary pleomorphic carcinomas (PPCs) are uncommon malignant tumours characterised by an aggressive clinical course and poor survival. These neoplasms frequently exhibit marked confluent necrosis, in which hypoxia levels are extremely high, causing low responsiveness to chemotherapy and conferring basic resistance to anti-cancer drugs. Programmed death ligand 1 (PD-L1)–mediated immune escape may be an underlying source of resistance and a suitable target for specific therapy, but its role in PPCs is unclear.

Materials and methods

In total, 122 PPCs were investigated. Paraffin-embedded tumour sections were stained with PD-L1 and hypoxia-inducible factor-1α (HIF-1α) antibodies. Overexpression was denoted by moderate-to-strong PD-L1 membrane staining in ≥5% of tumour cells and HIF-1α nuclear staining in ≥10% of tumour cells. The presence of driver mutations in the epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral oncogene homolog (KRAS), v-raf murine sarcoma viral oncogene homolog B (BRAF), telomerase reverse harscriptase gene (TERT), phosphoinositide 3-kinase catalytic alpha (PIK3CA), anaplastic lymphoma kinase (ALK), and ROS1 (ROS1 proto-oncogene receptor tyrosine kinase) genes were examined.

Results

The overall frequencies of PD-L1 and HIF-1α overexpression and EGFR mutation were 70.5, 75.4, and 22.1%, respectively. High PD-L1 expression was significantly correlated with that of HIF-1α (p < 0.001) and tumour necrosis (p < 0.001). HIF-1α expression was associated with EGFR mutation (p = 0.015). Advanced stage and high PD-L1 expression were two independent risks for poor overall survival.

Conclusions

High PD-L1 and HIF-1α co-expression was observed in PPCs compared with their expression in conventional non-small-cell lung carcinoma. The aggressive behaviour of PPC could be partially related to PD-L1–mediated immune escape and intratumoural hypoxia. High PD-L1 expression correlates with poor prognosis and may provide a rationale for the use of targeted immunotherapy in this subtype of high-grade PPC.

Introduction

Pulmonary pleomorphic carcinoma (PPC) is rare, comprising 0.1–1.6% of all lung malignancies.[1], [2] In PPC, the giant cell and/or spindle cell elements comprising at least 10% of the tumour are admixed with components such as adenocarcinoma, squamous cell carcinoma, or undifferentiated non-small-cell carcinoma.[3], [4] PPC has a more aggressive clinical course than non-small-cell lung cancer (NSCLC), and its response to chemotherapy and radiotherapy is generally poor,[4], [5] although a few patients partially responded to gefitinib.[2], [6] Little is known about the biology of these neoplasms and the mechanism of chemoresistance or radioresistance and progression. Recent reports also described that PPC has a worse outcome than NSCLC, and systemic therapy needs to be explored.[4], [7]

A recently developed therapeutic strategy is the use of anti-tumour immunotherapy, such as blockade of co-inhibitory immune pathways, in particular programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) signalling. Aberrant activation of co-inhibitory pathways is a key determent of local immunosuppression, and counteracting PD-1/PD-L1 signalling was demonstrated to promote strong and durable tumour regression in several solid tumours with minimal immune-related adverse effects for patients with advanced cancer.[8], [9], [10] Clinical trials using monoclonal antibodies targeting the PD-1/PD-L1 axis revealed promising anti-tumour activity in several malignancies, including lung carcinoma. Preliminary data from these trials suggest that tumour PD-L1 expression may predict response to these treatments.[11], [12] However, the correlation of PD-L1 expression in tumour cells with treatment response of anti-PD-1 or PD-L1 therapy is still undetermined. In terms of Nivolumab, high PD-L1 expression was correlated with better treatment response in non-squamous NSCLC13 but not in squamous cell carcinoma.14 The results were also inconsistent in other phase I/II clinical trials using different agents of PD-1/PD-L1 blockade.[10], [15] Besides the role of predictive biomarker, PD-L1 shows inconsistent results among various studies as a prognostic biomarker.[11], [12], [16], [17], [18], [19], [20], [21], [22], [23] These conflicting results may be caused by different assays for immunohistochemical (IHC) staining of PD-L1 and various cutoff values. More than 20 IHC antibodies have been studied to represent lung cancer PD-L1 expression, but the standardisation of IHC testing and the validation of optimal IHC assays still need more works to clarify.24 Moreover, the heterogeneous histology, staging, treatment, and the driver mutations in these may also contribute to this complex scenario. Currently, a fully human anti-PD-1 antibody, Nivolumab, has yielded significant survival benefits in phase III trials of refractory NSCLC, either squamous14 or non-squamous histology,25 and became the recommended subsequent treatment for NSCLC patients after failure of first-line chemotherapy in the NCCN guideline.26 In the context of clinical trials, PD-L1 protein expression on tumour cells detected by immunohistochemistry is currently the best predictive biomarker.[11], [12], [27]

It is conventionally accepted that coagulative necrosis, a common feature of solid tumours, is caused by chronic ischaemic injury, which suggests that the degree of tumour necrosis reflects the level of intratumoural hypoxia. Several recent reports suggested that hypoxia might induce epithelial–mesenchymal transition and cause conformational changes.28

Hypoxia-inducible factor 1-α (HIF-1α) is a major transcription factor that mediates adaptive responses to hypoxia, and the protein consists of HIF-1α and HIF-1β subunits. HIF-1α is the functional subunit, and it is regulated by oxygen levels. Meanwhile, HIF-1β is a constitutively expressed nuclear protein.29

Hypoxia causes a rapid, dramatic, and selective upregulation of PD-L1 on splenic myeloid-derived suppressor cells in tumour-bearing mice. It also significantly increases the expression of PD-L1 on macrophages, dendritic cells, and tumour cells. Furthermore, PD-L1 upregulation under hypoxia is dependent on HIF-1α.30

The goal of this study was to conduct a comprehensive investigation of PD-L1 and HIF-1α expression in a large series of patients with highly aggressive PPC and correlate their expression with clinicopathologic parameters and clinical outcomes, as well as the major driver mutations of NSCLC in East Asians.

Section snippets

Patient populations

The investigations were performed in a cohort of 122 individuals with PPC, including 42 cases from our previous reports,31 who were managed at the National Taiwan University Hospital between 30th January 1996 and 27th July 2015. The Hospital's Research Ethics Committee approved the study, and all patients provided written informed consent. PPCs were diagnosed according to the criteria set by the World Health Organisation.3

Clinical data were tabulated from each patient's medical records and

Patient demographics

Eighty-nine (73%) of the patients were men, and 33 (27%) patients were women (Table 1). Eighty-two (67.2%) patients were smokers. The mean age at diagnosis was 64.0 years (range, 23–93 years). The distribution of stages of PPC among the patients was as follows: stage I disease, 13 patients (10.7%); stage II disease, 15 patients (12.3%); stage III disease, 42 patients (34.4%); and stage IV disease, 52 patients (42.6%) (Table 1). Eighty-eight patients with advanced disease received chemotherapy,

Discussion

PPC is a rare, aggressive disease characterised by a high rate of early distant metastasis, late recognition, and ominous outcomes.[1], [31], [42] The etiologic and molecular events associated with this disease are almost entirely unknown. There are presently no available data indicating the optimal management of patients with advanced PPC.

Considerable evidence indicates that the EGFR pathway plays an important role in the pathogenesis of lung cancers. Patients with EGFR-mutated NSCLC respond

Conflict of interest statement

The authors declare no conflicts of interest.

Role of the funding sources

This study is funded by the National Taiwan University Hospital, Taipei, Taiwan (NTUH 105-S2939) for the conduct of the research and the Ministry of Science and Technology, Taiwan (104-2314-B-002-090) for the English editing and reproduction of colour artwork of this article.

Acknowledgements

The authors would like to thank Ms. Chih-Hsin Chen for her skillful technical support.

References (66)

  • S. Savic et al.

    Detection of ALK-positive non-small-cell lung cancers on cytological specimens: high accuracy of immunocytochemistry with the 5A4 clone

    J Thorac Oncol

    (2013)
  • K. Kaira et al.

    Pulmonary pleomorphic carcinoma. A clinicopathological study including EGFR mutation analysis

    J Thorac Oncol

    (2010)
  • X. Ma et al.

    Recurrent TERT promoter mutations in non-small cell lung cancers

    Lung Cancer

    (2014)
  • T. Vieira et al.

    Blood vessel invasion is a major feature and a factor of poor prognosis in sarcomatoid carcinoma of the lung

    Lung Cancer

    (2014)
  • D.E.B. Swinson et al.

    Interactions between hypoxia and epidermal growth factor receptor in non-small cell lung cancer

    Clin Lung Cancer

    (2006)
  • S. Park et al.

    Prognostic implications of hypoxia-inducible factor-1α in epidermal growth factor receptor-negative non-small cell lung cancer

    Lung Cancer

    (2011)
  • B. Vanselow et al.

    Oxygenation of advanced head and neck cancer: prognostic marker for the response to primary radiochemotherapy

    Otolaryngol Head Neck Surg

    (2000)
  • T. Vieira et al.

    Efficacy of the first-line chemotherapy in patients with advanced lung sarcomatoid carcinoma

    J Thorac Oncol

    (2013)
  • E. Giroux Leprieur et al.

    Clinical and molecular features in patients with advanced non-small-cell lung carcinoma refractory to first-line platinum-based chemotherapy

    Lung Cancer

    (2013)
  • S.Y. Liu et al.

    Clinicopathologic significance of tumor cell-lined vessel and microenvironment in oral squamous cell carcinoma

    Oral Oncol

    (2008)
  • P.A. Kyzas et al.

    Hypoxia-induced tumor angiogenic pathway in head and neck cancer: an in vivo study

    Cancer Lett

    (2005)
  • T. Azuma et al.

    B7–H1 is a ubiquitous antiapoptotic receptor on cancer cells

    Blood

    (2008)
  • V. Velcheti et al.

    Sarcomatoid lung carcinomas show high levels of programmed death ligand-1 (PD-L1)

    J Thorac Oncol

    (2013)
  • S. Kim et al.

    Programmed death-1 ligand 1 and 2 are highly expressed in pleomorphic carcinomas of the lung: comparison of sarcomatous and carcinomatous areas

    Eur J Cancer

    (2015)
  • C.Y. Yang et al.

    Programmed cell death-ligand 1 expression is associatied with a favourable immune microenvironment and better overall survival in stage 1 pulmonary squamous cell carcinoma

    Eur J Cancer

    (2016)
  • K.M. Kerr et al.

    Pleomorphic, spindle cell, and giant cell carcinoma

  • T. Mochizuki et al.

    Pleomorphic carcinoma of the lung: clinicopathologic characteristics of 70 cases

    Am J Surg Pathol

    (2008)
  • G. Rossi et al.

    Pulmonary carcinomas with pleomorphic, sarcomatoid, or sarcomatous elements: a clinicopathologic and immunohistochemical study of 78 cases

    Am J Surg Pathol

    (2003)
  • A. Ushiki et al.

    Genetic heterogeneity of EGFR mutation in pleomorphic carcinoma of the lung: response to gefitinib and clinical outcome

    Jpn J Clin Oncol

    (2009)
  • J.D. Wolchok et al.

    Nivolumab plus ipilimumab in advanced melanoma

    N Engl J Med

    (2013)
  • S.L. Topalian et al.

    Survival, durable tumor remission, and long-term safety in patients with advanced melanoma receiving nivolumab

    J Clin Oncol

    (2014)
  • R.S. Herbst et al.

    Predictive correlates of response to the anti-PD-L1 antibody MPDL3280A in cancer patients

    Nature

    (2014)
  • J.R. Brahmer et al.

    Safety and activity of anti-PD-L1 antibody in patient with advanced cancer

    N Engl J Med

    (2012)
  • Cited by (0)

    View full text