Non-triple Negative Cancer Research Articles

FOXA1 Protein Expression in ER+ and ER- Breast Cancer in Relation to Parity and Breastfeeding in Black and White Women.

Forkhead box protein A1 (FOXA1) promotes luminal differentiation, and hypermethylation of the gene can be a mechanism of developing estrogen receptor-negative (ER-) breast cancer. We examined FOXA1 in breast tumor and adjacent normal tissue in relation to reproductive factors, particularly higher parity and no breastfeeding, that are associated with ER- tumors. We performed IHC for FOXA1 in breast tumors (n = 1,329) and adjacent normal tissues (n = 298) in the Women's Circle of Health Study (949 Blacks and 380 Whites). Protein expression levels were summarized by histology (H) scores. Generalized linear models were used to assess FOXA1 protein expression in relation to reproductive factors by ER status. ER-positive (ER+) versus ER- tumors had higher FOXA1 protein expression (P < 0.001). FOXA1 expression was higher in tumor versus paired adjacent normal tissue in women with ER+ or non-triple-negative cancer (both P < 0.001), but not in those with ER- or triple-negative cancer. Higher number of births (1, 2, and 3+) was associated with lower FOXA1 protein expression in ER+ tumors [differences in H score, or β = -8.5; 95% confidence interval (CI), -15.1 to -2.0], particularly among parous women who never breastfed (β = -10.4; 95% CI, -19.7 to -1.0), but not among those who breastfed (β = -7.5; 95% CI, -16.9 to 1.8). The associations for ER- tumors were similar, although they were not statistically significant. In this tumor-based study, higher parity was associated with lower FOXA1 expression in ER+ tumors, and breastfeeding may ameliorate the influence. These findings contribute to our understanding of FOXA1 methylation and breast cancer etiology.

Correlation of Primary Tumor FDG Uptake with Clinicopathologic Prognostic Factors in Invasive Ductal Carcinoma of the Breast.

The purpose of this study was to investigate the correlation of primary tumor FDG uptake to clinicopathological prognostic factors in invasive ductal carcinoma of the breast. We retrospectively reviewed 136 of 215 female patients with pathologically proven invasive ductal breast cancer from January 2008 to December 2011 who underwent F-18 FDG PET/CT for initial staging and follow-up after curative treatment with analysis of estrogen receptor (ER), progesterone receptor (PR) and human epithelial growth factor receptor 2 (HER2). The maximum standardized uptake value (SUVmax) of the primary breast tumor was measured and compared with hormonal receptor and HER2 overexpression status. The high SUVmax of primary breast tumors is significantly correlated with the clinicopathological factors: tumor size, histologic grade, TNM stage, negativity of ER, negativity of PR, HER2 overexpression and triple negativity. The recurrent group with non-triple negative cancer had a higher SUVmax compared with the non-recurrent group, though no significant difference in FDG uptake was noted between the recurrence and non-recurrent groups in subjects with triple-negative cancer. Lymph node involvement was the independent risk factor for cancer recurrence in the multivariate analysis. In conclusion, high FDG uptake in primary breast tumors is significantly correlated with clinicopathological factors, such as tumor size, histologic grade, TNM stage, negativity of the hormonal receptor, HER2 overexpression and triple negativity. Therefore, FDG PET/CT is a helpful prognostic tool to direct the further management of patients with breast cancer.

Phenotypic Diversity of Breast Cancer-Related Mutations in Metalloproteinase-Disintegrin ADAM12

Six different somatic missense mutations in the human ADAM12 gene have been identified so far in breast cancer. Five of these mutations involve highly conserved residues in the extracellular domain of the transmembrane ADAM12-L protein. Two of these extracellular mutations, D301H and G479E, have been previously characterized in the context of mouse ADAM12. Three other mutations, T596A, R612Q, and G668A, have been reported more recently, and their effects on ADAM12-L protein structure/function are not known. Here, we show that ADAM12-L bearing the G668A mutation is largely retained in the endoplasmic reticulum in its nascent, full-length form, with an intact N-terminal pro-domain. The T596A and R612Q mutants are efficiently trafficked to the cell surface and proteolytically processed to remove their pro-domains. However, the T596A mutant shows decreased catalytic activity at the cell surface, while the R612Q mutant is fully active and comparable to the wild-type ADAM12-L. The D301H and G479E mutants, consistent with the corresponding D299H and G477E mutants of mouse ADAM12 described earlier, are not proteolytically processed and do not exhibit catalytic activity at the cell surface. Among all six breast cancer-associated mutations in ADAM12-L, mutations that preserve the activity - R612Q and L792F - occur in triple-negative breast cancers, while loss-of-function mutations - D301H, G479E, T596A, and G668A - are found in non-triple negative cancers. This apparent association between the catalytic activity of the mutants and the type of breast cancer supports a previously postulated role of an active ADAM12-L in the triple negative breast cancer disease.

Abstract P2-08-05: Functional characterization of three novel breast cancer-related somatic mutations in metalloproteinase-disintegrin ADAM12

Abstract Six different somatic missense mutations in the human ADAM12 gene have been identified so far in breast cancer. Five of these mutations involve highly conserved residues in the extracellular domain of the transmembrane ADAM12-L protein. Two of these extracellular mutations, D301H and G479E, have been previously characterized in the context of mouse ADAM12. Three other mutations, T596A, R612Q, and G668A, have been reported more recently, and their effects on ADAM12-L protein structure/function are not known. Here, we show that ADAM12-L bearing the G668A mutation is largely retained in the endoplasmic reticulum in its nascent, full-length form, with an intact N-terminal pro-domain. The T596A and R612Q mutants are efficiently trafficked to the cell surface and proteolytically processed to remove their pro-domains. However, the T596A mutant shows decreased catalytic activity at the cell surface, while the R612Q mutant is fully active and comparable to the wild-type ADAM12-L. The D301H and G479E mutants, consistent with the effect of the corresponding D229H and G477E mutations in mouse ADAM12 protein described earlier, are not proteolytically processed and do not exhibit catalytic activity at the cell surface. Among all six breast cancer-associated mutations in ADAM12-L, mutations that preserve the activity - R612Q and L792F - occur in triple-negative breast cancers, while loss-of-function mutations - D301H, G479E, T596A, and G668A - are found in non-triple negative cancers. This apparent association between the catalytic activity of the mutants and the type of breast cancer supports a previously postulated role of ADAM12-L in the triple negative breast cancer disease. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-08-05.

Disease-free Probability and Triple-Negative Breast Cancer

Objective: To compare the probabilities of local recurrence and distant metastasis between women with triple-negative and non- triple negative breast cancers.&#x0D; Methods: Medical and pathological records of breast cancer patients treated between the years 2002 and 2006 were reviewed.&#x0D; Results: There were 256 patients with complete data on estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) expression determinations. There were 54 patients (21%) with triple-negative (ER-, PR-, HER2 -) cancers. Triple-negative patients were more likely to have larger tumors with higher histologic grade. The median fallow-up time was 4 years. The probabilities of local and distant recurrence were similar between the two groups of patients. Only two factors were independently and significantly associated with overall recurrence: tumor stage and tumor size.&#x0D; Conclusion: Triple-negative breast cancer did not have a higher risk for both local recurrence and distant metastasis when compared with non-triple negative cancer.

Degree of Tumor FDG Uptake Correlates with Proliferation Index in Triple Negative Breast Cancer

2-Deoxy-2-[F-18]fluoro-D-glucose (FDG) uptake may be a useful surrogate marker for proliferation index, but the correlation has not always been clear-cut. Previous research by our group suggests that FDG-positron emission tomography (PET) is sensitive in detecting triple negative breast cancer. We therefore performed a pilot study to test if FDG uptake correlated with proliferation index in women with triple negative cancer. To determine whether proliferation index correlates with metabolic uptake of FDG in women with triple negative breast cancer, we performed a retrospective analysis correlating %Ki67 nuclear stain with tumor maximum standardized uptake values (SUVmax) in a group of 41 women, 22 with triple negative and 19 with non-triple negative breast cancer. As expected, [18F]-PET imaging was significantly more sensitive in detecting triple negative breast cancer than non-triple negative breast cancer, 95.5% vs 68.4% (p = 0.036). In general, SUVmax and %Ki67 nuclear stain values rise as histologic grade worsens. Histologic grade of triple negative breast cancer was more often poorly differentiated than non-triple negative cancer (p = 0.001). SUVmax correlated with %Ki67 nuclear staining in our entire cohort (spearman correlation = 0.485, p = 0.002). Moreover, this significant correlation appeared to be driven primarily by a subset of women with triple negative cancer (spearman correlation = 0.497, p = 0.019). Degree of tumor FDG uptake correlated significantly with proliferation index in women with triple negative breast cancer suggesting a potential role of FDG-PET in treatment response monitoring for this group of women. Future studies are necessary to define the role of PET imaging as a non-invasive means to monitor breast cancer treatment response in the neoadjuvant setting.