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Updated: Oct 3, 2026

Using 22C3 Anti-PD-L1 Antibody Concentrate on Biopsy and Cytology Samples from Non-small Cell Lung Cancer Patients
Published on: September 25, 2018
[Immunoelectron microscopic analysis of P-glycoprotein, p53, and Bcl-2 proteins expressions in lung cancer]
1Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
Objective:
To determine the ultrastructural localization of P-gp, p53 protein, and Bcl-2 protein in lung cancer cells, their relation to multidrug resistance and possible mechanisms of action.
Methods:
Expression of P-gp, p53, and Bcl-2 proteins was examined in 8 NSCLC surgical specimens and 7 SCLC bronchoscopically biopsied specimens using postembedding PAG immunolabelling technique for electron microscopy.
Results:
P-gp was detected on the cell membrane and the periphery of endoplasmic reticulum (ER). P53 protein was observed not only in the nuclei associated with heterochromatin but also in the cytosol. Bcl-2 protein immunoreactivity was associated with mitochondria and ER. P-gp, p53, and Bcl-2 were detected in 5(33%), 9(60%), and 4 (26.7%) out of the 15 samples examined, respectively. In 8 normal lung tissues, these three proteins were detected. Of 5 P-gp positive samples 4 were NSCLC, only 1 was SCLC after chemotherapy.
Conclusion:
P-gp, p53, and Bcl-2 proteins are detectable immuno-electron microscopically in lung cancer cells. No correlation in expression existed between of p53 and P-gp, nor did that between p53 and Bcl-2. The plasma membrane localization of P-gp supports its action as a transmembrane drug efflux pump. P-gp may play a role in MDR in lung cancer.