Quantitative multiplex methylation-specific PCR assay for the detection of promoter hypermethylation in multiple genes in breast cancer.

If detected early, breast cancer is eminently curable. To detect breast cancer in samples with little cellularity, a high level of sensitivity is needed. Tumor-specific promoter hypermethylation has provided such a valuable tool for detection of cancer cells in biological samples.

Very high frequency of hypermethylated genes in breast cancer metastasis to the bone, brain, and lung.

Purpose: Most often it is not the primary tumor, but metastasis to distant organs that results in the death of breast cancer patients. To characterize molecular alterations in breast cancer metastasis, we investigated the frequency of hypermethylation of five genes (Cyclin D2, RAR-beta, Twist, RASSF1A, and HIN-1) in metastasis to four common sites: lymph node, bone, brain, and lung.

Experimental Design: Methylation-specific PCR for the five genes was performed on DNA extracted from archival paraffin-embedded specimens of paired primary breast cancer and its lymph nodes (LN) metastasis (n = 25 each); in independent samples of metastasis to the bone (n = 12), brain (n = 8), and lung (n = 10); and in normal bone, brain, and lung (n = 22).

Estrogen receptor/progesterone receptor-negative breast cancers of young African-American women have a higher frequency of methylation of multiple genes than those of Caucasian women.

Purpose: To provide a molecular rationale for negative prognostic factors more prevalent in African-American (AA) than Caucasian (Cau) women, we investigated the frequency of promoter hypermethylation in invasive ductal breast cancers in the two races.

Experimental Design: HIN-1, Twist, Cyclin D2, RAR-beta, and RASSF1A were analyzed in DNA from 67 AA and 44 Cau invasive ductal breast cancers, stratified by age and estrogen receptor/progesterone receptor (ER/PR) status, by methylation-specific PCR. Hierarchical multiple logistic regression analysis was applied to determine estimated probabilities of methylation.

DNA methylation of RASSF1A, HIN-1, RAR-beta, Cyclin D2 and Twist in in situ and invasive lobular breast carcinoma.

Little is known about epigenetic silencing of genes by promoter hypermethylation in lobular breast cancers. The promoter methylation status of 5 cancer-related genes (RASSF1A, HIN-1, RAR-beta, Cyclin D2 and Twist) was evaluated in 2 types of lobular cancers, in situ (LCIS) and invasive lobular carcinomas (ILC) (n = 32), and compared to ductal in situ (DCIS) and invasive (IDC) breast cancers (n = 71). By using methylation-specific PCR (MSP), 100% of ILC and 69% of LCIS cases were found to have 1 or more hypermethylated genes among the panel of 5 genes (compared to 100% IDC and 95% of DCIS).