Clinicopathologic correlation of beclin-1 and bcl-2 expression in human breast cancer.
The human beclin-1 gene, located on chromosome 17q21, has been identified as the mammalian orthologue of Atg6 (autophagy-related gene) and may be a haploinsufficient tumor suppressor gene. The function and expression of beclin-1 in human breast cancer are largely unknown. We investigated the expression of beclin-1 and bcl-2 in human breast cancer. Tissue samples from 125 cases of invasive breast cancer were used for the present study. Immunohistochemical staining for beclin-1 and bcl-2 was evaluated using tissue microarray, then the 2 proteins were correlated with clinicopathologic parameters. Positive beclin-1 expression and bcl-2 expression in breast cancer tissue were observed in 53 cases (42.4%) and 48 cases (38.4%), respectively. Beclin-1 expression was inversely correlated with bcl-2 expression in breast cancer tissue (P = .035). Beclin-1 expression significantly correlated with nuclear pleomorphism and mitotic count. Bcl-2 expression in breast cancer tissue significantly correlated with histologic grade, tubule formation, nuclear pleomorphism, mitotic count, estrogen receptor, and distant metastasis. Our results suggest that beclin-1 might play a role in the inhibition of the development of breast cancer and that inhibition might be due to an interaction with bcl-2 protein.
Won
Kyu Yeoun
KY
Department of Pathology, East-West Neo Medical Center, College of Medicine, Kyung Hee University, Seoul 134-727, Republic of Korea.
Kim
Gou Young
GY
Kim
Youn Wha
YW
Song
Jeong Yoon
JY
Lim
Sung-Jig
SJ
D000328:Adult; D000368:Aged; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D000071186:Beclin-1; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism* / Q000401:mortality / Q000556:secondary; D002467:Cell Nucleus / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D042361:Mammary Glands, Human / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D008938:Mitosis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D015996:Survival Rate; D046888:Tissue Array Analysis; D055815:Young Adult
D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; D014408:Biomarkers, Tumor; D008565:Membrane Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011960:Receptors, Estrogen