CD55 and CD59 expression protects HER2-overexpressing breast cancer cells from trastuzumab-induced complement-dependent cytotoxicity

Abstract

A large proportion (40–60%) of patients with human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer do not benefit from trastuzumab treatment, potentially due to the lack of complement-dependent cytotoxicity (CDC) activation. In the present study, the effect of complement decay-accelerating factor (CD55) and CD59 glycoprotein precursor (CD59) expression on trastuzumab-induced CDC in HER2-positive breast cancer cell lines was investigated. The CD55 and CD59-overexpressing and HER2-positive cell lines SK-BR-3 and BT474 were selected for subsequent experiments. Blocking CD55 and CD59 function using targeting monoclonal antibodies significantly enhanced the cell lysis of SK-BR-3 and BT474 cells following treatment with trastuzumab. In addition, following treatment with 0.1 U/ml phosphatidylinositol-specific phospholipase C (PI-PLC) for 1 h, CD55 and CD59 surface expression was significantly decreased, and the cell lysis rate was further enhanced. Treatment of SK-BR-3 cells with short hairpin RNA (shRNA) targeting CD55 and CD59 downregulated CD55 and CD59 expression at the mRNA and protein levels, and resulted in significantly enhanced trastuzumab-induced CDC-dependent lysis. The data from the present study suggested that CD55 and CD59 serve roles in blocking trastuzumab-induced CDC, therefore strategies targeting CD55 and CD59 may overcome breast cancer cell resistance to trastuzumab. The results from the present study may provide a basis for developing suitable, personalized treatment strategies to improve the clinical efficacy of trastuzumab for patients with HER2-positive breast cancer.

Demonstrating Analytical Similarity of Trastuzumab Biosimilar HLX02 to Herceptin® with a Panel of Sensitive and Orthogonal Methods Including a Novel FcγRIIIa Affinity Chromatography Technology

“…The dot plots of a HER2 binding affinity by ELISA, b HER2 binding affinity by SPR, c anti-proliferation activity, and d ADCC activity were plotted above corresponding equiva-lence test results showing 90% CI. ADCC antibody-dependent cellmediated cytotoxicity, CI confidence interval, ELISA enzyme-linked immunosorbent assay, HER2 human epidermal growth factor receptor 2, SPR surface plasmon resonance protein in HER2-overexpressing breast cancer cells inhibited trastuzumab-induced CDC [28]. Accordingly, binding to the complement cascade component protein, C1q, and CDC were assessed as tier 3 attributes.…”

Complement system's role in cancer and its therapeutic potential in ovarian cancer

“…The most studied of these mCRPs, CD59, has been inhibited by a recombinant inhibitor (rILYd4), and by mAb, with promising results that showed lowering of resistance in mAb therapy for lymphoma and lung cancer, respectively . Furthermore, a recent study has shown that blocking expression or binding of CD55 and CD59 via various methods have unequivocally increased tumour lysis by trastuzumab in breast cancer cell lines . Downregulating CD55 via RNA interference in combination with rituximab in human B‐cell lymphoma cells has also yielded promising results .…”

“…49,50 Furthermore, a recent study has shown that blocking expression or binding of CD55 and CD59 via various methods have unequivocally increased tumour lysis by trastuzumab in breast cancer cell lines. 51 Downregulating CD55 via RNA interference in combination with rituximab in human B-cell lymphoma cells has also yielded promising results. 52 As mCRPs are ubiquitously expressed on healthy cells, antibodies against mCRPs have to be targeted to the tumour microenvironment.…”

Effect of membrane‑bound complement regulatory proteins on tumor cell sensitivity to complement‑dependent cytolysis triggered by heterologous expression of the α‑gal xenoantigen

“…In a retrospective study evaluating the effectiveness of using the monoclonal antibody (mAb) therapy trastuzumab against Her2-positive breast cancer, patients overexpressing CD55 or CD59 had a higher relapse rate and a shorter mean disease-free survival time than those with low expression of CD55 or CD59; the expression of CD46 had no effect on prognosis ( 26 ). In another study, it also suggested that CD55 and CD59 served roles in blocking trastuzumab-induced CDC in Her2-positive cells ( 27 ). Therefore, the overexpression of mCRPs may be a main factor behind the observed divergences in sensitivity to cell lysis by NHS among diverse α-gal-expressing tumor cells.…”