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BZLF1 mRNA and the product, an immediate-early gene for EBV replication, was not expressed in any of them, thereby suggesting that the tumour cells carried EBV genomes in a tightly latent form.
 BZLF1 mRNA, tumour cells, immediate-early gene, EBV genomes
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:
 BZLF1 mRNA, tumour cells, immediate-early gene, EBV genomes