1966
The level of mRNA expression of the NM23 gene is significantly lower in cell lines that derive from more infiltrating primary melanomas than in cell lines obtained from less infiltrating tumours .
 cell line: cell lines; DNA: NM23 gene; protein: NM23; cell line: cell lines
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: cell lines, NM23 gene, NM23, cell lines 
Answer:
 cell line: cell lines; DNA: NM23 gene; protein: NM23; cell line: cell lines