Reduced expression of the breast cancer metastasis suppressor 1 mRNA is correlated with poor progress in breast cancer.
OBJECTIVE
It is well established that breast cancer metastasis suppressor 1 (BRMS1) suppresses metastasis of breast cancer in animal models without affecting the growth of the primary tumor. It has also been shown to suppress the metastasis of tumors derived from breast and melanoma cell lines. However, its clinical importance for breast cancer patients remains undetermined. This prompted us to investigate its expression level in breast cancer patients to clarify its clinical significance.


METHODS
The level of expression of BRMS1 mRNA was assessed by LightCycler quantitative real-time reverse transcription-PCR in 161 cases of invasive carcinoma of the breast. Associations between BRMS1 mRNA expression and various clinicopathologic factors were sought.


RESULTS
It was found that BRMS1 mRNA was expressed at significantly higher levels in patients>50 years of age, with tumor size<2 cm, or with progesterone receptor-positive and HER2-negative tumors. No differences were found between BRMS1 mRNA expression and axillary lymph node metastasis and histologic grade groups. Patients with high levels of expression of BRMS1 mRNA have a better prognosis than those with low expression. Univariate and multivariate prognostic analysis showed that BRMS1 mRNA is an independent prognostic factor for disease-free survival in breast cancer.


CONCLUSIONS
These results provide clinical evidence to support the notion that BRMS1 is a breast carcinoma metastasis suppressor gene. Our results also suggest that measuring BRMS1 expression will help to identify those breast cancer patients with worse disease-free survival.
Zhang
Zhenhuan
Z
Department of Breast and Endocrine Surgery, Nagoya City University Hospital, Nagoya, Japan.
Yamashita
Hiroko
H
Toyama
Tatsuya
T
Yamamoto
Yutaka
Y
Kawasoe
Teru
T
Iwase
Hirotaka
H
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis / Q000473:pathology; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D011379:Prognosis; D012333:RNA, Messenger / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012097:Repressor Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D011980:Receptors, Progesterone; D012097:Repressor Proteins; C410024:BRMS1 protein, human