Correlation of steroid receptors with histologic differentiation in mammary carcinoma. A Singapore experience

A modular analysis of breast cancer reveals a novel low-grade molecular signature in estrogen receptor-positive tumors

PURPOSE

Previous reports using genome-wide gene expression data to classify breast tumors have typically used standard unsupervised or supervised techniques, both of which have known limitations. We hypothesized that novel clinically relevant information could be revealed in these data sets by an alternative analytic approach. Using a recently described algorithm, signature analysis (SA), we identified "modules," comprising groups of tightly coexpressed genes that are conditionally linked to particular tumors, in a series of breast tumor gene expression profiles.

EXPERIMENTAL DESIGN AND RESULTS

The SA successfully identified multiple breast cancer modules specifically linked to distinct biological functions. We identified a novel module, TuM1, whose presence was not readily discernible by conventional clustering techniques. The TuM1 module is expressed in a subset of estrogen receptor (ER)-positive tumors and is significantly enriched with genes involved in apoptosis and cell death. Clinically, TuM1-expressing tumors are associated with low histopathologic grade, and this association is independent of the inherent ER status of a tumor. We confirmed the robustness and general applicability of TuM1 module by demonstrating its association with low tumor grade in multiple independent breast cancer data sets generated using different array technologies. In vitro, the TuM1 module is down-regulated in ER+ MCF7 cells upon treatment with tamoxifen, suggesting that TuM1 expression may be dependent on active signaling by ER. Initial data is also suggestive that TuM1 expression may be clinically associated with a patient's response to antihormonal therapy.

CONCLUSION

Our results suggest that modular-based approaches toward gene expression data can prove useful in identifying novel, robust, and biologically relevant signatures even from data sets that have been the subject of substantial prior analysis.

Progesterone receptor expression is a marker for early stage breast cancer: implications for progesterone receptor as a therapeutic tool and target

We determined the association of estrogen receptor (ER) and progesterone receptor (PR) expression in invasive breast cancer with stage at diagnosis. Univariate analyses indicated that although ER and PR expression were inversely associated with grade (P<0.0001), only PR expression (P<0.01) was inversely associated with stage. Multivariate analyses, adjusted for covariates, including HER-2/neu expression, indicated that PR (odds ratio (OR), 0.88; confidence interval (CI), 0.77-0.99; P=0.03) and not ER expression (OR, 1.04; CI, 0.94-1.16; P=0.45) was inversely associated with stage. PR and not ER expression is a marker for early stage breast cancer.

Hormone receptors and proliferation in breast carcinomas of equivalent histologic grades in pre- and postmenopausal women

Breast cancers in younger, premenopausal women are more likely to exhibit an adverse prognostic profile (including negative steroid hormone receptors and a high rate of cellular proliferation) and poor outcome than breast cancers in postmenopausal women. It has been hypothesized that this adverse prognostic profile is a result of the higher histologic grade of breast cancers in pre- compared with post-menopausal women. To assess the association of expression of steroid hormone receptors and indicators of proliferation while controlling for histologic grade, we identified 100 infiltrating ductal carcinomas from premenopausal women 45 years of age or younger and 100 from postmenopausal women 65 years of age or older. The carcinomas were selected so that the histologic grades (low versus high) were distributed equally between the 2 groups. Estrogen receptors (ER), progesterone receptors (PR), p27(Kip1) and Ki-67 (to measure rate of proliferation) were assessed by immunohistochemistry and compared between groups. Clinical information and survival data were also analyzed. ER content was lower and proliferation was higher in carcinomas in premenopausal women (p = 0.048 and p = 0.005, respectively). By univariate analysis, p27(Kip1) and PR were not different between the groups; however, in multivariate analysis, p27(Kip1) was higher in postmenopausal women, but only in a subgroup with highly proliferative carcinomas. Overall survival was similar in the pre- and postmenopausal women. Furthermore, low p27(Kip1) and African-American ethnicity predicted a poorer overall survival in the premenopausal, but not in the postmenopausal, women in our study. After controlling for histologic grade, a lower expression of ER and a higher proliferative index were detected in breast carcinomas in premenopausal women. Therefore, some prognostic indicators, such as ER and proliferative rate, may be more closely associated with menopausal status than histologic grade. Our data also suggest that some prognostic factors are not equally effective as predictors of survival in pre- and postmenopausal women.

Hormonal receptor determination of 1,052 Chinese breast cancers

BACKGROUND AND OBJECTIVES

Hormonal receptors are important prognostic factors for breast cancer. The reported figures in the literature are mostly on Caucasians. This study analyzes the receptor profile of 1,052 Chinese patients.

METHODS

The age of the patients ranged from 20-93 years; 48% were premenopausal and 52% postmenopausal. Estrogen receptor (ER) and progesterone receptor (PgR) were measured quantitatively by enzyme immunoassay (EIA) using the rat monoclonal antibody (ABBOTT ER-EIA). Specimens with values >15 fmol/mg were considered positive according to manufacturer's recommendation.

RESULTS

ER was positive in 53% and 61.6% of the pre- and postmenopausal women respectively (P < 0.0075); PgR was positive in 51.5% and 46.2% respectively (P > 0.05). The mean values of ER were higher for postmenopausal women (P < 0.0001) but the values for PgR were similar between the two groups (P > 0.05). When the values were analyzed with respect to age, there was an increasing trend for ER. No such trend was noted for PgR. Subgroup analysis showed that there were more ER+PgR+ tumors among postmenopausal than among premenopausal women. Tumors with dubious receptor status (ER+PgR- or ER-PgR+) were more prevalent at perimenopausal age.

CONCLUSIONS

Chinese patients have lower receptor values and positivity rates than those reported for Caucasians. Receptor-positive tumors tend to occur in postmenopausal women.

Prognostic factors. Stage and receptor status in breast cancer

BACKGROUND

Anatomic and biologic indicators of prognosis provide the bases for management of patients with cancer of the breast. Combinations of these indicators are potentially more accurate than any alone. This review was undertaken to evaluate the prognostic relationship between stage and steroid hormone receptors.

METHODS

The literature was reviewed relative to the influences of tumor size, axillary metastases, and tumor estrogen receptors on the survival of patients with cancer of the breast.

RESULTS

Axillary node status is of primary importance as a predictor of recurrence and survival. Tumor size has only a secondary influence, but is prognostically useful in the absence of metastases. Estrogen and progesterone receptors provide prognostic information that is independent of axillary stage, but the influence is weak, often transient, and attributable at least partly to a close association with other biologic indicators of favorable prognosis.

CONCLUSIONS

Hormone receptors add to the prognostic information provided by anatomic stage, but the contribution is insufficient to support a decision for or against systemic adjuvant therapy.

Analysis of cytosol CA15-3, carcinoembryonic antigen, estrogen and progesterone receptors in breast cancer tissues

Cytosol levels of carcinoembryonic antigen (CEA), CA15-3, estrogen receptor (ER) and progesterone receptor (PgR) of 194 primary breast cancer tissues were measured. ER and PgR determined by enzyme immunoassay methods correlated inversely with Page's grades of histological atypia and mitotic rate. Cytosol CA15-3 correlated inversely with the grades of tubular and nuclear atypia and positively with the mitotic rate. CA15-3 correlated positively with ER and PgR. Cytosol CEA showed no correlation with the pathological grade or hormone receptor status. These results indicate that hormone receptor-positive breast cancers tend to have more differentiated morphology and slower growth rate than those without those receptors and that the cytosol CA15-3 level may reflect some of the intrinsic malignant potency, particularly the growth rate, of breast cancer. Cytosol CA15-3 as well as the hormone receptor status may have prognostic value for patients with breast cancer.

Oestrogen and progesterone receptors in men with bilateral or unilateral pubertal macromastia

Abnormalities at the tissue receptor level may be important in the pathophysiology of pubertal macromastia, which may be unilateral or bilateral. We studied breast tissue removed from seven boys of age 16-17 years, five with bilateral and two with unilateral gynaecomastia. We confirmed that their physical features, karyotype, and plasma concentrations of testosterone, oestradiol, LH, FSH, and prolactin were all normal for adolescent males. Oestrogen and progesterone receptors were measured with a steroid binding (dextran coated charcoal) assay which was used for breast cancer receptor studies. Oestrogen receptors were not detectable in any of the 12 breasts studied. Progesterone receptors were detectable at a low level in two patients with bilateral gynaecomastia, one breast from each patient. We conclude that although the development of bilateral or unilateral male macromastia in puberty may yet be mediated by a local tissue receptor abnormality, this disorder is probably not mediated by an abnormal increase in oestrogen receptor number.

The relationship of hepatocellular carcinoma and liver cirrhosis to hepatitis B virus infection in the Philippines

The relationship between hepatitis B virus (HBV) infection and cirrhosis (CIR) and hepatocellular carcinoma (HCC) was investigated. 340 cases with HCC and 99 cases with CIR were compared with the control group which were asymoptomatic age- and sex-matched case. Both HCC and CIR have higher infection rated of HBV and the positivity rated of HBsAg than their controls in both sexes. The positivity rate (74.8%) of HBsAg in HCC is significantly higher than that (58.2%) in CIR. HBeAg is more frequently positive in CIR than in HCC, especially among females. There was no sex difference in HBsAg positive among HCC nor among CIR. Age-adjusted AFP elevation is significantly more frequent in HBsAg-positive HCC than in HBsAg-negative. Both HCC and CIR in the Philippines are closely associated with HBV infection. The association with the infection is stronger with HCC than with CIR. Other causative/contributary factors may be important, especially with CIR. However, the great majority of HCC are probably due to chronic HBV infection, the public health control of which may result in a significant diminution of the malignancy in the country.

Clinical correlation of hormone receptor status in epithelial ovarian cancer

Cytoplasmic estrogen receptor (ER) and progesterone receptor (PR) levels were measured in ovarian epithelial carcinomas from 37 patients using a dextran-coated charcoal assay prior to any treatment. Sixty-eight percent of the tumors were ER positive, forty-nine percent were PR positive, forty-one percent were positive for both receptors, and twenty-seven percent were negative for both receptors. Receptor status in epithelial ovarian carcinomas was found to have no clinical significance when correlated with age, parity, race, cigarette smoking, surgical stage, histologic type, histologic grade, progression-free interval, or patient survival.

Immunohistochemical demonstration of steroid C21 hydroxylase in normal and neoplastic human breasts

Steroid C21 hydroxylase was investigated immunohistochemically with the use of antibody against cytochrome P-450 specific for steroid C21 hydroxylation (P-450C21) in normal and neoplastic human breast tissues. In the histologically normal breast, P-450C21 was exclusively present in secretory tubules and ducts. In mammary dysplasia and fibroadenoma, P-450C21 was intensively stained in epithelial cells. In gynecomastia, P-450C21 was faintly observed in epithelial cells in some cases. In intraductal and invasive ductal carcinoma, P-450C21 was observed in the cells with ductal formation. P-450C21 was not observed in medullary and mucinous carcinoma. In lobular carcinoma, only two cases were positive for P-450C21 of nine cases examined. P-450C21 is considered to be closely related to the ductal differentiation in neoplastic transformation of the breast.