In vitro and in vivo evidences propound therapeutic potential of Lipocalin 2 in cervical carcinoma
Cervical cancer (CC), the second most common in developing countries and the third most common in developed nations, is the fourth most common type of cancer in women overall. The HPV16 high-risk genotype of the virus, which is responsible for about 61% of cervical cancer incidences, was found to have higher LCN2 levels in advanced clinical CC stages. In this study, we assessed the impact of suppressing LCN2 activity after treatment with an anti-LCN2 monoclonal antibody (MAb) in both in vitro and in vivo settings. Anti-LCN2 antibody was found to reduce proliferation and invasion of HeLa cells, the first immortal cells from a HPV positive aggressive adenocarcinoma of the cervix. LCN2 and its ligand MMP9 was found to be highly expressed in the cells and abrogated on treatment with anti-LCN2. The five receptors of LCN2 - SLC22A17, MC1R, MC2R, MC4R and LRP2 were barely detected with or without treatment. Anti-LCN2 Mab caused tumors to regress and soften in vivo, in a xenograft mouse model. Analysis of histology images of the treated and untreated tumor established the necrotic capability of the therapeutic molecule explaining the regression and softening of the tumor. Differential gene expression analysis between untreated and treated tumor proved that LCN2 inhibition abolished the migratory, invasive, and hypoxic pathways while significantly increasing the necrosis and cell death pathways in tumor after treatment with the monoclonal antibody. LCN2 inhibition was shown molecularly to lead to tumor regression via a negative feedback loop of LCN2 through the TNF-IL17 axis exponentially increasing the effect of the anti-LCN2 monoclonal antibody. In conclusion, LCN2 appears to be a viable therapeutic target, and the monoclonal antibody used in this study can be further developed for clinical usage in cervical cancer.