BACKGROUND Circular RNAs (circRNAs) are widely expressed in mammals and can regulate the development and progression of human tumors. has_circ_0015758 (circ-CFH) is an exon circRNA transcript from the GRCh37/hg19 fragment of chromosome 1 and is homologous to the protein-coding gene complement factor H (CFH).
This recombinant CFH antibody causes complement activation and release of anaphylatoxins, promotes CDC of tumor cell lines, and inhibits tumor growth in vivo.
Also, in adenocarcinoma of the lung, Kaplan-Meier survival analysis showed a tendency that CFH-positive tumors had worse prognosis in comparison to CFH-negative tumors (p=0.082).
Further examination including other complement regulatory proteins showed that combining antitumor PDT with antibody-mediated neutralization of factor H (soluble negative complement regulator) or injection of properdin (positive complement regulator) increased the cure rates of PDT-treated tumors.
A soluble complement inhibitor factor H (FH) and its splice variant factor H-like protein (FHL) have been recently discovered to play a major role in malignant cell escape from complement-mediated cytotoxicity in lung-, ovarian- and glia-derived neoplasms.
In conclusion, we show that expression of the complement inhibitor factor H by lung cancer cells can prevent complement activation and improve tumor development in vivo.