Immunohistochemistries (IHCs) with anti-MMR proteins (MLH1, PMS2, MSH2 and MSH6) and multiplex IHCs with anti-PD-L1, anti-CD8 or anti-CD163 were performed on tissue microarrays (TMAs) with 101 triple-negative BCs (TNBC) and 197 HER2-positive BCs.
We assessed the rates of the recurring Ashkenazi Jewish (AJ) mutations in the MSH6 gene (c.3984_3987dupGTCA and c.3959_3962delCAAG) in AJ cases with seemingly sporadic BC or HBOC phenotype, who were negative for the founder AJ BRCA1/2 mutations.
Our data demonstrate that two LS genes, MSH6 and PMS2, are associated with an increased risk for breast cancer and should be considered when ordering genetic testing for individuals who have a personal and/or family history of breast cancer.
The breast cancer targeting peptide p160 (12-mer) and its enzymatically stable analogue 18-4 (10-mer) showed marked potential for breast cancer drug delivery using cell studies and animal models.
Using targeted capture and massively parallel genomic sequencing, 151 subjects with USC were assessed for germline mutations in 30 tumor suppressor genes, including BRCA1 (breast cancer 1, early onset), BRCA2, the DNA mismatch repair genes (MLH1 [mutL homolog 1], MSH2 [mutS homolog 2], MSH6, PMS2 [postmeiotic segregation increased 2]), TP53 (tumor protein p53), and 10 other genes in the Fanconi anemia-BRCA pathway.
Promoter hypermethylation of PAX6, BRCA2, PAX5, WT1, CDH13 and MSH6 seems to be a frequent early event in breast cancer and methylation levels of GSTP1 (and CDKN2A, although still low) seem to increase with increasing DCIS grade.
However, screening of the entire MSH6 coding sequence in 68 non-HBCC breast cancer families showed a similar association (8.8 vs. approximately 1.4% in controls, P < or = 0.001), suggesting that rare MSH6 variants are not confined to HBCC breast cancer.
Using unconditional logistic regression we found that MLH3 (L844P, G>A) polymorphism GA (Leu/Pro) and AA (Pro/Pro) genotypes were associated with a decreased risk: OR = 0.65 (0.45-0.95) (p = 0.03) and OR = 0.62 (0.41-0.94) (p = 0.03), respectively.Analysis of two-way SNP interaction effects on breast cancer revealed two potential associations to breast cancer susceptibility: MSH3 Ala1045Thr/MSH6Gly39Glu - AA/TC [OR = 0.43 (0.21-0.83), p = 0.01] associated with a decreased risk; and MSH4 Ala97Thr/MLH3 Leu844Pro - AG/AA [OR = 2.35 (1.23-4.49), p = 0.01], GG/AA [OR = 2.11 (1.12-3,98), p = 0.02], and GG/AG [adjusted OR = 1.88 (1.12-3.15), p = 0.02] all associated with an increased risk for breast cancer.
AIB1 (amplified in breast cancer 1), also called SRC-3 and NCoA-3, is a member of the p160 nuclear receptor co-activator family and is considered an important oncogene in breast cancer.
The p160 nuclear receptor coactivator, AIB1 (amplified in breast cancer 1), is frequently overexpressed in human breast cancer and has been shown to be associated with tamoxifen resistance.
Using data/samples collected from the first 752 Caucasians and 141 African-Americans in an ongoing case-control study, we examined the association between breast cancer risk and 18 non-synonymous single-nucleotide polymorphisms (nsSNPs) in four DNA repair pathways-(i) base excision repair: ADPRT V762A, APE1 D148E, XRCC1 R194W/R280H/R399Q and POLD1 R119H; (ii) nucleotide excision repair: ERCC2 D312N/K751Q, ERCC4 R415Q, ERCC5 D1104H and XPC A499V/K939Q; (iii) mismatch repair: MLH1 I219V, MSH3 R940Q/T1036A and MSH6G39E and (iv) double-strand break repair: NBS1 E185Q and XRCC3 T241M.
Overexpression or amplification of ACTR (also named AIB1, RAC3, p/CIP, TRAM-1, and SRC-3), a member of the p160 family of coactivators for nuclear hormone receptors, has been frequently detected in multiple types of human tumors, including breast cancer.
The p160 nuclear receptor coactivator, AIB1 (amplified in breast cancer 1), is frequently amplified and overexpressed in human breast cancer and has been shown to enhance estrogen-dependent transactivation.
Using a genetic approach, we show that recruitment of the p160 class of coactivators is sufficient for gene activation and for the growth stimulatory actions of estrogen in breast cancer supporting a model in which ER cofactors play unique roles in estrogen signaling.