Epidermal growth factor receptor up-regulation is associated with lung growth after lobectomy

Ann Thorac Surg. 2001 Aug;72(2):380-5. doi: 10.1016/s0003-4975(01)02797-7.


Background: We hypothesized that compensatory lung growth after lobectomy is characterized by a combination of cellular hyperplasia and hypertrophy and that up-regulation of epidermal growth factor receptor (EGFR) is involved in these processes.

Methods: Age-matched mature pigs were divided into four groups. The control group (group C) did not have operation. Two groups underwent left upper lobectomy and were studied 2 weeks (group L2) or 3 months (group L3) later. The last group underwent a sham left thoracotomy, and the left lower lobe was harvested 2 weeks later for EGFR analysis. Left lower lobes were studied using wet weight, cell proliferation index through immunostaining for 5-bromo-2'-deoxyuridine, morphometry, and Western blot analysis for EGFR. Content of protein and DNA (deoxyribonucleic acid) in the lung tissue was also determined.

Results: Left lower lobe weights were elevated in both groups L2 and L3 compared with group C. We noted a significant rise in the proliferation index, with a concomitant increase in EGFR expression, in group L2 compared with group C. In group L3, there was an increase in the protein to DNA ratio compared with group C.

Conclusions: We conclude that compensatory lung growth after lobectomy comprises an early increase in the cell proliferation index (ie, cellular hyperplasia) and a late increase in the protein to DNA ratio (ie, cellular hypertrophy). The early proliferative phase is associated with EGFR up-regulation.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cell Division / genetics
  • DNA / genetics
  • ErbB Receptors / genetics*
  • Gene Expression
  • Lung / growth & development*
  • Lung / pathology
  • Organ Size
  • Pneumonectomy*
  • Swine
  • Swine, Miniature
  • Up-Regulation / genetics


  • DNA
  • ErbB Receptors