Introduction/Background Ovarian cancer is the most lethal gynecological cancer often termed as a ‘Silent Killer’. It is difficult to diagnose ovarian cancer at early stages as no alarming symptoms are known. A cost effective and non-invasive simple early screening method for ovarian cancer is needed urgently to reduce high mortality rate. Saliva is a clinically informative unique fluid, which is useful for novel approaches to prognosis, clinical diagnosis and monitoring for non-invasive detection of a disease.

Methodology Differential proteomic expression analysis to identify protein markers of ovarian cancer in human saliva was performed by fluorescence-based 2D-DIGE and a number of proteins were identified by MALDI/TOF-MS. Expression of selective differentially expressed proteins was also validated by western blotting, ELISA and immunohistochemistry. RT-PCR was performed in an independent cohort of ovarian tumor tissues to check the presence of the proteins at m-RNA level.

Results A number of differentially expressed proteins were identified and few of them, viz. Multimerin1, Fibroblast Growth Factor 8, Zinc Finger protein 525 and Cystatins SA were validated. Significant over expression of these proteins was observed with fold changes more than 2–3 with p<0.01. Cytoplasmic expression of these upregulated proteins in ovarian cancer tissue were also observed by immunohistochemistry to confirm our proteomics findings. High intensity of these proteins was observed in ovarian cancerous tissues. Furthermore, mRNA expression of these salivary signatures confirms their presence at gene level in both ovarian cancer patients and normal healthy controls. As evident from relative expression analysis of target genes by RT-PCR, mRNA levels of all the targets were found differentially expressed in disease compared to healthy controls.

Conclusion These differentially expressed proteins can further be explored as plausible markers for screening of ovarian cancer.

Disclosure Nothing to disclose.