Sperm protein 17 expression by murine epithelial ovarian cancer cells and its impact on tumor progression

Qian Gao, Sue D. Xiang, Kirsty Wilson, Mutsa Madondo, Andrew N. Stephens, Magdalena Plebanski

Research output: Contribution to journalArticleResearchpeer-review

7 Citations (Scopus)


The cancer testis antigen sperm protein 17 (Sp17) is a promising antigenic target in epithelial ovarian cancer (EOC) vaccine development. However, its role in ovarian cancer is unclear. We isolated and expanded Sp17+ and Sp17− clones from the murine EOC cell line ID8, and compared their in-vitro cell growth characteristics and in-vivo tumorigenicity. We also examined the potential co-expression of molecules that may influence cancer cell survival and interaction with immune cells. These include stimulatory and immunosuppressive molecules, such as major histocompatibility class I molecules (MHC I), MHC II, cytotoxic T lymphocyte associated antigen-4 (CTLA-4), CD73, CD39, tumor necrosis factor receptor II (TNFRII), signal transducer and activator of transcription 3 (STAT3) and programmed death-ligand 1 (PD-L1). Whilst the presence of Sp17 was not correlated with the ID8 cell proliferation/growth capacity in vitro, it was critical to enable progressive tumor formation in vivo. Flow cytometry revealed that Sp17+ ID8 cells displayed higher expression of both STAT3 and PD-L1, whilst MHC II expression was lower. Moreover, Sp17high (PD-L1+ MHCII−) cell populations showed significantly enhanced resistance to Paclitaxel-induced cell death in vitro compared to Sp17low (PD-L1− MHCII+) cells, which was associated in turn with increased STAT3 expression. Together, the data support Sp17 as a factor associated with in-vivo tumor progression and chemo-resistance, validating it as a suitable target for vaccine development.

Original languageEnglish
Article number276
Number of pages15
Issue number8
Publication statusPublished - 20 Aug 2018


  • ID8
  • Immune evasion
  • MHC II
  • Paclitaxel
  • PD-l1
  • Sperm protein 17 (Sp17)
  • STAT3
  • Tumor resistant

Cite this