Direct Profiling of Proteins Distribution in Cervical Invasive Cancer by Matrix Assisted Laser Desorption Ionization Mass Spectrometry

Abstract

Objective To analyze the distribution of proteins in cervical invasive cancer which were profiled directly by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Methods A saturated sinapinic acid (SA) solution was prepared at the concentration of 35 mg/mL in 50: 50 acetonitrile/0.1% TFA in water. Matrix sinapinic acid solution was deposited onto tissue sections by using a low-volume pipette. Samples were analyzed directly by matrix assisted laser desorption ionization time of flight mass spectrometry. Results A total of 25 types of candidate proteins were screened, and 7 candidate proteins were significant (m/z 3 433, m/z 4786, m/z 10 092, m/z 10 835, m/z 15 114, m/z 15 854, m/z 16 345). Importantly, candidate proteins m/z 3 433, m/z 15 114 and m/z 15 854 were expressed overly in the epithelium of cervical cancer, whereas candidate protein m/z 16 345 was expressed highly in the stromal extracellular matrix (ECM) of cervical cancer. Conclusions The differences of expressions and distributions of candidate proteins were found in the epithelium between cervical cancer and normal control group, suggesting that these candidate proteins may be as now biomarkers to be used in improving the predictive value of cervical invasive cancer. Key words: squamous carcinoma of the cervix (SCC); early infiltrate; proteomic difference; matrix assisted laser desorption ionization time of flight mass spectrometry(MALDI-TOF-MS)