14363
Northern blot analysis revealed in these cells, an increase in the transcription of these two proto-oncogenes , and this increase was amplified after treatment with phorbol myristate acetate .
 proto-oncogenes
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:
 proto-oncogenes