14121
In addition, this proliferative parameter maintained its prognostic significance when the patients were stratified according to lymph node involvement , menopausal status , and nuclear estrogen receptor content .
 nuclear estrogen receptor
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 nuclear estrogen receptor