B2M and breast cancer: In addition, no significant correlations were found between β2-M transcript expression level and age, clinical stage or lymph node metastasis; 18.67% (31/166) up-regulation, 28.92% (48/166) down-regulation and 52.41% (87/166) no change in expression of Bcl-2 transcripts were observed in the breast cancer specimens, and no significant correlations were found between Bcl-2 transcript expression level and age, clinical stage or lymph node metastasis.