Identification of Potential Markers Related to Neoadjuvant Chemotherapy Sensitivity of Breast Cancer by SELDI-TOF MS

Neoadjuvant chemotherapy (NACT) is known to be beneficial for patients with locally advanced breast cancer. However, there is still no unified standard on the evaluation of NACT. To identify the potential markers related to NACT sensitivity of breast cancer, in the present study, we examined the protein spectrum of breast cancer tissues before and after NACT using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). Totally, 87 protein samples were extracted from tissues of breast cancer, with 30 from patients before NACT, 30 from patients after NACT, and 27 from patients without any treatment. To eliminate confounding factors a couple of tissue samples from the same patient were mixed. SELDI-TOF MS analysis demonstrated that the intensities of eight different protein peaks, i.e., 26,055.46, 17,898.94, 8,949.50, 11,652.02, 11,053.48, 38,546.56, 5,825.89, and 22,250.63 Da, were higher in samples after NACT than those before NACT. Although further experiments are needed to prove the reliability of the proteins identified in this study, our results will help the establishment of protein model based on drug resistance-related protein peaks to screen whether a patient is suitable for adopting NACT and to improve cancer treatment.