Abstract P3-01-03: Vitamin D levels at breast cancer diagnosis: Association with patient and tumor characteristics

Background: Despite many preclinical studies showing the anti-neoplastic effects of vitamin D on breast cancer, findings from epidemiologic studies and randomized trials remain inconclusive. It is possible that tumor heterogeneity in breast cancer may mask these associations. Variations in vitamin D metabolism may explain some racial disparities in breast cancer. We aimed to examine the association of serum vitamin D levels with individual patient and tumor characteristics.

Methods: We conducted an IRB approved retrospective chart review, identifying all breast cancer patients with documented pretreatment serum levels of 25-hydroxyvitamin D (25(OH)D) between February 2011-May 2013. The following clinical data were collected for each patient: age at diagnosis, ethnicity, menopausal status, tumor size (mm), lymph node status, estrogen receptor (ER), progesterone receptor (PR), and HER2 status. Based on ER, PR, and HER2, patients were categorized into three molecular subtypes: 1) Hormone receptor (HR)+ (ER or PR positive, HER2 negative), 2) HER2+, and 3) triple negative (TN; ER, PR, and HER2 negative). Descriptive variables were analyzed using a one-way Anova test.

Results: Among the 200 breast cancer patients identified, the mean age was 55.9 years (range 29-90). Ethnicities of the patients were as follows: 104 (52%) Caucasian, 43 (22%) African American, 29 (15%) Hispanic, and 16 (8%) Asian. Seventy six patients (38%) were premenopausal, and 124 (62%) were postmenopausal. African Americans were found to have higher rates of triple negative tumors compared to all other ethnicities (24.4% vs. 11.6%, p = 0.029). Younger women had lower mean serum 25(OH)D levels compared to older women (p = 0.033). Lower mean 25(OH)D levels were seen in ER negative tumors compared to ER positive tumors (p = 0.0102). Mean 25(OH)D levels were lower in African American, Hispanic, and Asian breast cancer patients when compared to Caucasians (p = 0.0004). When stratifying by menopausal status, serum 25(OH)D levels differed more by tumor characteristics among premenopausal women than postmenopausal women. In premenopausal women, lower vitamin D levels were seen in patients who were African Americans (p = 0.0185), and with tumors that were ER negative (p = 0.0083). There was also a trend toward lower mean vitamin D levels in those with TN breast cancer compared to other molecular subtypes.

Conclusion: In premenopausal women, lower vitamin D levels were associated with African American race, younger age, and ER negative tumors. This may suggest that African Americans have defective vitamin D metabolism that may contribute to a more aggressive breast cancer phenotype. Further studies are warranted.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-01-03.

Abstract P3-08-08: Vitamin D status at breast cancer diagnosis: correlation with patient and tumor characteristics

Background: Despite many preclinical studies showing anti-neoplastic activities of vitamin D on breast cancer, findings from epidemiologic studies and randomized trials on the relationship between vitamin D and breast cancer remains inconclusive. It is possible that tumor heterogeneity in breast cancer may mask these associations. Variations in vitamin D metabolism might explain some racial disparities in breast cancer. We aimed to examine the association of serum vitamin D levels with patient and tumor characteristics.

Methods: We conducted an IRB approved retrospective chart review, identifying all breast cancer patients with documented pretreatment serum level of 25-hydroxyvitamin D (25(OH)D) between February 2011-May 2012. The following clinical data were collected for each patient: age at diagnosis, ethnicity, menopausal status, largest tumor size (mm), lymph node status, estrogen receptor (ER), progesterone receptor (PR), and HER2 status. Based on ER, PR, and HER2, patients were categorized into three molecular subtypes: 1) Hormone receptor (HR)+ (ER or PR positive, HER2 negative), HER2+, triple negative (TN) (ER, PR, and HER2 negative). Vitamin D deficiency, insufficiency, and sufficiency were defined as 25(OH)D <20 ng/mL, 20–29 ng/mL, and ≥30 ng/mL, respectively. Descriptive variables were analyzed using one-way Anova test. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from logistic regression models.

Results: Among 86 breast cancer patients identified, median age was 60 years (range 27–88). Ethnicities of the patients: 47 (55%) Caucasian, 18 (21%) African American, 15 (17%) Hispanic, and 6 (7%) Asian. Twenty eight (33%) were premenopausal, and 58 (67%) were postmenopausal. African Americans had the lowest mean 25(OH)D levels among different ethnicities (p = 0.0042). Patients with tumors >2 cm had lower mean vitamin D levels compared to those with tumors ≤ 2 cm (p = 0.037). When stratifying by menopausal status, serum 25(OH)D levels differed more by tumor characteristics among premenopausal women than postmenopausal women. In premenopausal women, lower vitamin D levels were seen in patients who were African Americans (p < 0.001), with large tumor size (p < 0.001), and with tumors that were ER negative (p = 0.003). There was also a trend toward lower mean vitamin D levels in those with TN breast cancer compared to other molecular subtypes. In subgroup analysis, being African American and having TN breast cancer significantly correlates with having vitamin D deficiency (p = 0.0001).

Conclusion: In premenopausal women, lower vitamin D levels were associated with African American race, larger tumor size, and ER negativity. African Americans with TN breast cancer were more likely to be vitamin D deficient. This might support the hypothesis that African Americans have defective vitamin D metabolism that may contribute to a more aggressive breast cancer phenotype. Further studies are warranted.

Transcriptional switching model for the regulation of tumorigenesis and metastasis by the ha-ras oncogene - transcriptional changes in the ha-ras tumor-suppressor gene lysyl oxidase

A model system is described that allows an analysis of the molecular and biochemical changes associated with expression and suppression of the oncogenic and metastatic phenotype of cloned rat embryo fibroblast (CREF) cells. Ha-ras-transformed CREF cells are morphologically transformed, anchorage-independent and both tumorigenic and metastatic in athymic nude mice and syngeneic Fischer rats. Co-expression of the Ha-ras oncogene and Krev-1 tumor suppressor gene in CREF cells results in suppression of in vitro transformation. In contrast, Ha-ras/Krev-1 transformed CREF cells retain, with greatly extended latency periods, both tumorigenic and metastatic capabilities in athymic nude mice. The present study investigates changes in the Ha-ms suppressor gene, rrg (lysyl oxidase), during expression and suppression of the oncogenic phenotype in CREF cells. Nontumorigenic CREF cells and CREF cells transformed by the Ha-ras and Krev-1 gene that express a suppression in in vitro transformation contain elevated levels of lysyl oxidase mRNA and protein. In contrast, Ha-ms and Ha-ras/Krev-1 nude mouse tumor- and nude mouse lung metastasis-derived CREF cells contain reduced levels of lysyl oxidase mRNA and protein. Nuclear run-on assays indicate that suppression of lysyl oxidase expression in transformed subclones of CREF cells correlates with a reduction in transcription of the lysyl oxidase gene. Taken together, the current studies support a transcriptional switching model in which lysyl oxidase expression correlates directly with suppression of the Ka-ms-induced transformation phenotype and escape from oncogenic suppression correlates with a transcriptional silencing of the lysyl oxidase gene and decreased lysyl oxidase mRNA and protein.

Postmastectomy radiotherapy: clinical practice guidelines of the American Society of Clinical Oncology

OBJECTIVE

To determine indications for the use of postmastectomy radiotherapy (PMRT) for patients with invasive breast cancer with involved axillary lymph nodes or locally advanced disease who receive systemic therapy. These guidelines are intended for use in the care of patients outside of clinical trials.

POTENTIAL INTERVENTION

The benefits and risks of PMRT in such patients, as well as subgroups of these patients, were considered. The details of the PMRT technique were also evaluated.

OUTCOMES

The outcomes considered included freedom from local-regional recurrence, survival (disease-free and overall), and long-term toxicity.

EVIDENCE

An expert multidisciplinary panel reviewed pertinent information from the published literature through July 2000; certain investigators were contacted for more recent and, in some cases, unpublished information. A computerized search was performed of MEDLINE data; directed searches based on the bibliographies of primary articles were also performed.

VALUES

Levels of evidence and guideline grades were assigned by the Panel using standard criteria. A "recommendation" was made when level I or II evidence was available and there was consensus as to its meaning. A "suggestion" was made based on level III, IV, or V evidence and there was consensus as to its meaning. Areas of clinical importance were pointed out where guidelines could not be formulated due to insufficient evidence or lack of consensus.

RECOMMENDATIONS

The recommendations, suggestions, and expert opinions of the Panel are described in this article.

VALIDATION

Seven outside reviewers, the American Society of Clinical Oncology (ASCO) Health Services Research Committee members, and the ASCO Board of Directors reviewed this document.

The relationship between genetic damage from polycyclic aromatic hydrocarbons in breast tissue and breast cancer

A number of polycyclic aromatic hydrocarbons (PAH) are widespread environmental contaminants that cause mammary cancer experimentally. We investigated whether exposure and susceptibility to PAH, as measured by PAH-DNA adducts in breast tissue, are associated with human breast cancer. We carried out a hospital-based case-control study using immunohistochemical methods to analyze PAH-DNA adducts in tumor and nontumor breast tissue from cases and benign breast tissue from controls. The subjects were white, African-American and Latina women without prior cancer or treatment, including 119 women with breast cancer and 108 with benign breast disease without atypia. PAH-DNA adducts measured in breast tumor tissue of 100 cases and in normal tissue from 105 controls were significantly associated with breast cancer (OR=4.43, 96% CI 1.09-18.01) after controlling for known breast cancer risk factors and current active and passive smoking, and dietary PAH. There was substantial interindividual (17-fold) variability in adducts overall, with 27% of cases and 13% of controls having elevated adducts. The odds ratio for elevated adducts in tumor tissue compared with control tissue was 2.56 (1. 05-6.24), after controlling for potential confounders. Adduct levels in tumor tissue did not vary by stage or tumor size. Among 86 cases with paired tumor and nontumor tissue, adducts levels in these two tissues were highly correlated (r=0.56, P<0.001). However, the corresponding associations between case-control status and adducts measured in nontumor tissue from 90 cases and in normal tissue from 105 controls were positive but not statistically significant. Overall, neither active nor passive smoking, or dietary PAH were significantly associated with PAH-DNA adducts or breast cancer case-control status. These results suggest that genetic damage reflecting individual exposure and susceptibility to PAH may play a role in breast cancer; but more research is needed to determine whether the findings are relevant to causation or progression of breast cancer.

Short-term outcome of chronic immunosuppression on the development of breast lesions in premenopausal heart and lung transplant patients

The risk of development of breast lesions in patients on chronic immunosuppression is unknown. In order to assess this risk, a retrospective review was performed of the records of 87 women between the ages of 12 and 47 years who received thoracic organ transplant from 1987 to 1996 at our institution. Inclusion criteria consisted of patients who were premenopausal, had no previous history of breast disease, and survived for at least 1 year posttransplantation. All patients were on a triple immunosuppressive regimen consisting of cyclosporine, steroids, and azathioprine. Mean follow-up was 4 +/- 1.2 years with a range of 1-6 years. During this period, 21 patients (24%) with a mean age of 38 +/- 10 years had screening or diagnostic mammography. The remainder of patients with a mean age of 24 +/- 9 years were followed clinically. Overall, 10 patients (11%) developed a total of 17 palpable, solid lesions at 33 to 72 months posttransplantation. Fifteen of these lesions were surgically excised. Five of the patients had multiple lesions. Pathological examination of the specimens revealed fibroadenoma in nine, fibrocystic disease in four, low grade phylloides tumor in one, and T-cell lymphoma in one case. None of the patients have developed primary breast cancer during follow-up. In conclusion, short-term immunosuppression does not increase the risk of the development of benign breast lesions in young women after thoracic organ transplantation, but rather the distribution of benign lesions is similar in an age-matched population. There were several cases of multiple fibroadenomas in the transplant population, but mammography revealed no malignant disease in this age group and does not need to be utilized in this population beyond what is considered standard for immunocompetent patients. The long-term effect ofimmunosuppressive therapy on the developmentof breast cancer in this group remains to be defined.

Organochlorine compounds (DDE and PCB) in plasma and breast cyst fluid of women with benign breast disease

The organochlorines, dichloro-diphenyl-trichloroethane and polychlorinated biphenyl (PCB) are pervasive environmental contaminants. Results from previous studies have been conflicting regarding the relationship between the internal dose of these organochlorine residues and breast cancer risk. To determine whether these compounds are present in breast cyst fluids and whether cyst fluid and plasma concentrations are correlated, we analyzed organochlorines in paired cyst fluid and plasma samples from 24 subjects using gas chromatography and electron capture detection. All but one of the women had a history of multiple cysts, suggesting that they were at elevated risk for future breast cancer. DDE (a metabolite of dichloro-diphenyl-trichloroethane) was present in 22 of the cyst samples and PCB was detected in 19 of the cyst samples. Organochlorine levels were more concentrated in the plasma than in breast cyst fluids. Levels of DDE in plasma were significantly correlated with those in cyst fluid (r = 0.73; P < 0.001); in contrast to PCB levels in cyst and plasma (r = 0.37; P = 0.12). Congener specific analysis of the PCBs showed that some individual congeners were preferentially excluded from or concentrated in the cyst fluid. To our knowledge, this study is the first to demonstrate that PCB and DDE are present in cyst fluids and thus in contact with the ductal epithelium of the breast. These results support the use of plasma DDE as a proxy for DDE in the target tissue in research on the role of environmental factors in breast cancer.

Immediate breast reconstruction in patients with locally advanced disease

Immediate breast reconstruction for patients with early-stage disease is well established. This study evaluates a consecutive series of 22 patients with locally advanced disease (stage IIB or III) who underwent mastectomy and immediate breast reconstruction. All patients received several cycles of neoadjuvant chemotherapy (average, 3.5 cycles) followed by completion of chemotherapy beginning approximately 3 weeks following surgery. The perioperative morbidity was 14% and no patient suffered a delay in the resumption of chemotherapy. Patients have been particularly grateful about being offered reconstruction in this setting. Our preliminary results with this technique have been encouraging and further study is warranted.

Carcinogen-DNA adducts in human breast tissue

Breast cancer is the second leading cause of cancer death among American women. Known risk factors account for only approximately one-third of the 182,000 new cases diagnosed each year in the United States. There is both concern and debate over the contribution of environmental exposures related to lifestyle, occupation, and ambient pollution, particularly in high risk areas such as Long Island, NY and the rest of the northeastern United States. Biomarkers such as carcinogen-DNA adducts can help to explore the role of environmental risk factors for breast cancer by documenting DNA damage from specific carcinogens directly in human tissue. In this pilot study, a total of 31 breast tissue samples were analyzed by the 32P-postlabeling method for carcinogen-DNA adducts characteristic of complex mixtures of aromatic compounds (such as polycyclic aromatic hydrocarbons) and tobacco smoke. The samples included tumor and tumor-adjacent tissues from 15 women with breast cancer and normal tissue samples from 4 women undergoing breast reduction. Among the breast cancer cases, the mean aromatic/hydrophobic-DNA adduct level in all tissues assayed was 5.3 +/- 2.4 (SD) adducts/10(8) nucleotides compared to 2.3 +/- 1.5 among the samples from the noncancer patients. Breast tissue (tumor and/or nontumor) from 30% (5 of 15) of women with breast cancer displayed a pattern of adducts (referred to as a diagonal zone of radioactivity) associated previously, in studies of other tissues, with exposure to tobacco smoke. The 5 positive samples were from current smokers; tissue samples from the 8 nonsmoking cases did not show this characteristic pattern (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Radioimmunoimaging of human breast carcinoma xenografts in nude mouse model with 111In-labeled new monoclonal antibody EBA-1 and F(ab')2 fragments

Radioimmunoimaging characteristics of a new monoclonal antibody EBA-1 and its F(ab')2 fragments utilizing nu/nu mice bearing human breast carcinoma xenografts are described. 111In-DTPA conjugates of EBA-1 localized with tumor/blood ratios of 0.99 +/- 0.10 (P < 0.3) and 4.65 +/- 1.60 (P < 0.05), and localization indices of 1.25 and 2.61 at 24 and 72 h, respectively. A tumor/blood ratio as high as 28.86 +/- 6.90 (P < 0.025) was obtained with EBA-1 F(ab')2 radioconjugates at 48 h. These results suggest that EBA-1 and its F(ab')2 might be useful reagents in radioimmunoimaging and radioimmunotherapy.

Importance of adequate staging and of hormone receptors in women older than age 70 with breast cancer

This report includes 479 women older than 70 years of age who were operated on between January 1980 and January 1988 and who were followed for 2.5 to 10.5 years (mean, 4.6 years). There were no operative deaths. Staging was available on 90.8%. Eighty-one per cent of patients were estrogen receptor positive (ER+), and 64% had negative lymph nodes (LN-). There were 50 deaths from breast cancer (10.4%), and 56 (11.6%) from other causes (mostly cardiovascular). Estrogen receptor negativity was significant by both univariate and multivariate analysis for increased risk of death from breast cancer (by factors of 3 and 1.4). Only four of 152 (2.6%) women who were node negative and estrogen receptor positive died during the follow-up of 4.9 years. The results of this study suggest that elderly women should be fully staged with axillary node dissections, and the hormone receptor assay should be performed because these are important indicators of prognosis. Because only 2.6% of the LN- and ER+ women in this study died of breast cancer, and only 3% in this group were treated with adjuvant systemic therapy (tamoxifen), the authors conclude that this therapy is unnecessary, although a prospective randomized study of elderly women would be required to state this definitively.

Modulation of the antigenic phenotype of human breast carcinoma cells by modifiers of protein kinase C activity and recombinant human interferons

In the present study we have analyzed the effect of a synthetic protein kinase C (PKC) activator 3-(N-acetylamino)-5-(N-decyl-N-methylamino)-benzyl alcohol (ADMB) and the natural PKC-activating tumor-promoting agents 12-O-tetradecanoylphorbol 13-acetate (TPA) and mezerein on the antigenic phenotype of T47D human breast carcinoma cells. All three agents increased the surface expression of the tumor-associated antigen BCA 225 and various cellular antigens, including HLA class II antigens, intercellular adhesion molecule 1 (ICAM-1) and c-erbB-2. Expression of the same antigens was also upregulated to various extents in T47D cells by recombinant fibroblast (IFN beta) and immune (IFN gamma) interferon. Shedding of BCA 225 from T47D cells was induced by TPA, mezerein, IFN beta and IFN gamma, whereas ADMB did not display this activity. The ability of ADMB, TPA and mezerein to modulate the antigenic phenotype of T47D cells appears to involve a PKC-mediated pathway, since the PKC inhibitor, H-7, eliminates antigenic modulation. In contrast, the ability of IFN beta and IFN gamma to enhance the synthesis, expression and shedding of BCA 225, as well as to enhance HLA class II antigens, c-erbB-2 and ICAM-1 expression, was either unchanged or modestly reduced by simultaneous exposure to H-7. Analysis of steady-state mRNA levels for HLA class I antigens, HLA class II-DR beta antigen, ICAM-1 and c-erbB-2 indicated that the ability of H-7 to inhibit expression of these antigens in TPA-, mezerein- and ADMB-treated cells was not a consequence of a reduction in the steady-state levels of mRNAs for these antigens. The results of the present investigation indicate that the biochemical pathways mediating enhanced antigenic expression in T47D cells induced by TPA, mezerein and the synthetic PKC activator ADMB are different from those induced by recombinant interferons. Furthermore, up-regulation of antigenic expression in T47D cells can occur by a PKC-dependent or a PKC-independent pathway.

Tumor localization in nude mice bearing human breast carcinoma xenografts using 111In-DTPA conjugates of monoclonal antibodies

Biodistribution of monoclonal antibody T43 and its F(ab')2 111In-DTPA conjugates were determined in nu/nu mice bearing human breast tumor and rat pituitary tumor xenografts. T43 localized in the target tumor with tumor/blood ratios of 3.9 (P less than 0.01) and 4.5 (P less than 0.05) at 48 and 72 h, respectively. T43 F(ab')2 fragments localized with tumor/blood ratio of 14.2 (P less than 0.1) at 72 h. Tumors as small as 4 mm were detected without computer subtraction technique. These studies suggest that T43 and T43 F(ab')2 might be useful reagents in radioimaging.

Mammographic features of intracystic papillary lesions

In this article, the mammographic findings of ten patients with intracystic papillary lesions are reported. Two of these patients also had sonograms, which confirmed the presence of intracystic papillary fronds. Although not all intracystic lesions can be differentiated from gross cysts, there are several helpful roentgenologic and clinical clues. The tumor presents mammographically as a sharply circumscribed cystic mass with an irregular and sometimes nodular contour, except where tumor breaks through the wall of the cyst to invade the parenchyma. There the borders become shaggy. This tumor should be suspected clinically if a cystic lesion is seen in a postmenopausal woman not taking estrogens. Management depends on a high degree of suspicion, and a sonogram is useful to visualize the papillary fronds in the cysts. Although malignant papillary lesions are often large on presentation, they carry an excellent prognosis that is not related to their size. Treatment consists of either mastectomy or lumpectomy and radiation, with or without dissection of axillary nodes.

Fine needle aspiration biopsy of intramammary neurilemoma

A case of benign neurilemoma (schwannoma) arising in the breast is presented, including the fine needle aspiration (FNA) biopsy findings. The aspirate yielded a cellular smear composed of clusters of spindle-shaped cells showing minimal atypia. The absence of mitotic figures and breast epithelium suggested a benign neoplasm. The final diagnosis was established on the excised mass by histopathologic study and the use of special stains. The utility and pitfalls of FNA biopsy in diagnosing this rare entity are discussed.

Stage I and II breast carcinoma: treatment with limited surgery and radiation therapy versus mastectomy

Between 1980 and 1986, 2,140 patients with surgical stage I or II breast carcinoma were treated including 1,179 patients with T1-2N0 disease and 961 patients with T1-2N1 disease. Among the 1,179 patients without node involvement, 215 underwent limited surgery (complete excision and axillary node dissection) and radiation therapy; 964 patients underwent modified radical mastectomy only. Of the 961 patients with node involvement, 106 were treated by means of limited surgery and radiation therapy; of these, 48 also received chemotherapy. The remaining 855 patients underwent mastectomy; of these, 381 also received chemotherapy and/or hormone therapy. The 5-year survival rates for patients with no node involvement were 96% for the group treated by means of limited surgery and radiation therapy and 88% for the group treated by means of mastectomy (P greater than .05). The 5-year survival rates for patients with node involvement were 96% for the group treated by means of limited surgery and radiation therapy with or without chemotherapy and 77% for the group treated by means of mastectomy with or without chemotherapy (P less than .01). This study demonstrates no disadvantage from treatment by means of limited surgery and radiation therapy and suggests that adjuvant radiation therapy may be important in increasing survival among patients with T1-2 breast carcinoma and positive axillary nodes.

Phototoxic liposomes coupled to an antibody that alone cannot modulate its cell-surface antigen kill selected target cells

Molecules such as antibodies that bind to cell surfaces can be used to deliver cytotoxic drugs to selected cells. To be effective the drug must usually be taken into the cells by endocytosis. In this study a T-cell line (CCRF-CEM) was effectively killed by liposomes carrying a photosensitizer and bearing the antibody OKT4 (anti-CD4). The unconjugated antibody does not induce antigenic modulation in the target cells, an indication of the absence of endocytosis, and would therefore not normally have been selected as an agent for drug delivery. It cannot, however, be concluded with certainty that the conjugates act at the cell surface and several alternative explanations of their efficacy are offered.

Increased surface expression and shedding of tumor associated antigens by human breast carcinoma cells treated with recombinant human interferons or phorbol ester tumor promoters

In the present study we have evaluated the effect of recombinant interferons, including leukocyte (IFN-alpha A), fibroblast (IFN-beta) and immune (IFN-gamma), and the tumor promoting agent 12-0-tetradecanoyl-phorbol-13-acetate (TPA) on the expression of tumor associated antigens (TAA) and class II HLA-DR antigens on human breast carcinoma cell lines. The effect of these agents on the shedding of a high molecular weight tumor associated glycoprotein, BCA-225, was also determined. All three interferons and TPA enhanced the expression of the Mr 180,000 carcinoembryonic antigen (CEA) and CEA-related TAA recognized by monoclonal antibody B1.1 in both T47D and MCF-7 human breast carcinoma cell lines. The three types of interferons and TPA differed in their absolute TAA-augmenting ability, even in single-cell subclones derived from MCF-7 cells and previously shown to display a differential susceptibility to IFN-alpha augmentation of B1.1 expression. In general, IFN-gamma was more effective than IFN-alpha, IFN-beta or TPA in augmenting the expression of TAA, CEA and BCA-225, and HLA-DR expression in T47D and MCF-7 cells. Differences were also apparent in the ability of the three interferon preparations and TPA to induce shedding of BCA-225 in T47D and MCF-7 cells and their subclones. As observed with TAA expression, IFN-gamma was the most effective preparation in inducing TAA shedding. IFN-gamma also induced the expression and the shedding of BCA-225 by a subclone of T47D cells, T47D cl 17, which normally displays a reduced expression of BCA-225 and does not spontaneously shed this TAA without exposure to IFN-gamma. Recombinant leukocyte interferon (IFN-alpha A) also enhanced BCA-225 expression on T47D cells grown as xenografts in nude mice in vivo. The results of the present study emphasize the complexity of potential antigenic responses which can be induced in human breast carcinoma cells when they are exposed to biological response modulators, including different types of interferon, and tumor promoting agents, such as TPA. This investigation also indicates that both classes of agents can differentially augment expression and/or shedding of TAA by specific breast carcinoma cell lines as well as subclones derived from the same breast carcinoma cell line.

Monoclonal antibodies: their importance to surgeons

A tremendous technological advance occurred in 1975 when a method was developed to fuse two cells producing a "hybridoma" which secretes a single clone of antibody, having one immunoglobulin (Ig) class, one structure, one affinity, and one specificity for an antigenic determinant. Because monoclonal antibodies are more precise reagents than conventional antisera they open new doors to diagnosis and therapy of disease, and they are useful tools in research. The pathologist uses monoclonals in immunocytochemistry to determine tumor type; the surgeon uses monoclonals for immunosuppression in renal transplantation; the immunologist uses monoclonals to decipher cellular and humoral interactions that could not be appreciated with polyclonal reagents. This review outlines the background of monoclonal antibodies and some of their clinically important uses, both in vitro and in vivo. We also project into the future and describe chimeric antibodies and their possible uses.

Selective killing of T lymphocytes by phototoxic liposomes

Two-fold specificity in drug delivery obtained through the localized activation of drugs by physical means and the attachment of drugs to proteins that bind to target cells might be used for highly selective cancer chemotherapy or for immunosuppression. Toward this end, a monoclonal antibody against an antigen on the surface of T lymphocytes was covalently attached to liposomes containing a phototoxic drug, pyrene, bound to the lipid bilayer. When unfractionated peripheral blood lymphocytes, or B- and T-cell lines, were irradiated after treatment with these liposomes, T cells were killed while B cells were spared, demonstrating the validity of the approach in a simple in vitro assay.

The extent and distribution of cancer in breasts with palpable primary tumors

The term multicentricity has been employed to describe cancer cells beyond the borders of the primary tumor. However, it is not clear if there are multiple independent sites of origin or if the process simply represents spread of the cancer. The present study was designed to examine the distribution and extent of cancer in the breast and identify factors that bear on these events. All mastectomy specimens between 1980 and 1983 were systematically examined by means of multiple sections. One hundred seventy-nine of 657 patients (27%) were found to have separate foci. The most common histologic type (invasive ductal) was least likely to have multifocal disease (19%), while it was extremely common in the small group of patients with intraductal lesions (81%). Size was a factor in ductal but not in lobular lesions. Ninety per cent of the secondary foci were found in close proximity to the primary, suggesting spread rather than multicentricity. This implies a more limited and predictable distribution of cancer cells and opens the way to more rational selection and surgical preparation of patients for breast preservation.

Non-human primate (baboon) anti-gross cystic disease fluid protein-15 antibody infusion in four women with metastatic breast carcinoma

Four women with metastatic breast carcinoma and elevated plasma levels of human breast gross cystic disease fluid protein of 15,000 dalton monomer size (GCDFP-15) were treated IV with non-human primate (baboon) anti-GCDFP-15 antibody. Three patients were given a single IV infusion of antibody, while the fourth patient received four sequential IV infusions. Antibody dosage patients, after antibody infusion the plasma level of GCDFP-15 decreased to 0 ng/ml and remained there as long as "free" circulating anti-GCDFP-15 antibody was present. The plasma half-life of the antibody ranged between 1 and 40 h and the duration of detectable free antibody ranged from 6 to 240 h. No toxicity was observed for the dosage range of antibody tested. No anti-baboon antibody response was detected. In the patient who received four sequential infusions of antibody partial regression of subcutaneous metastatic nodules occurred. The other three patients showed no clinically detectable changes from the antibody infusion.

Immunoreactivity and biodistribution of indium-111-labeled monoclonal antibody to a human high molecular weight-melanoma associated antigen

The anti-human, high molecular weight-melanoma associated antigen (HMW-MAA) MoAb 225.28S was chelated with 111In and then tested for its in vitro reactivity with cultured human melanoma cells and for its biodistribution in human melanoma bearing nude mice. In vitro studies showed that the radiolabeled antibody reacted specifically with cultured melanoma cells. However, binding of DTPA to the monoclonal antibody reduced its titer with cultured melanoma cells from 1:1024 to 1:512. Further labeling of the DTPA-antibody conjugate with 111In caused an additional reduction of its titer to 1:128. Injection of the radiolabeled monoclonal antibody into nude mice resulted in the accumulation of significantly (p less than 0.001) higher radioactivity in melanoma tissue than in nude mice injected with either [111In] chloride or 111In-labeled antibody to human acid phosphatase. The specificity of the distribution of the radiolabeled antibody in nude mice also was indicated by its poor localization in lesions other than melanoma (e.g., human prostate carcinoma and chronic abscess). The localization of antibody in liver and kidney was also high, although lower than that achieved in tumor. These results indicate that 111In-labeled monoclonal antibodies to human tumor associated antigens may be useful for localizing malignant lesions. However, there is a need to improve labeling and/or purification of antibody in order to decrease renal and hepatic activity.

Diagnosis of cutaneous T cell lymphoma by use of monoclonal antibodies reactive with tumor-associated antigens

Two murine monoclonal antibodies (BE1 and BE2), produced by using leukemic helper T cells from a patient with cutaneous T-cell lymphoma (CTCL) as immunogens, reacted selectively with CTCL lymphocytes and some transformed cultured lymphocytes, as determined by radioimmunoassay (RIA) and indirect immunofluorescence (IIF). BE1 reacted significantly (P less than or equal to 0.001) with leukemic CTCL lymphocytes and with CTCL cells from infiltrated lymph nodes (RIA, mean +/- SD = 776 +/- 275 cpm), as compared with background counts (263 +/- 68). BE1 binding to normal blood mononuclear cells (RIA, mean +/- SD = 283 +/- 58 cpm) was indistinguishable from background. BE1 also reacted with Epstein-Barr virus (EBV)-transformed B-cell lines (RIA, mean +/- SD = 794 +/- 230) and some long-term T-cell lines. BE1 did not react with the majority of lymphoid cell lines or tumor cell lines tested. BE1 also did not react with any normal tissues screened by IIF. BE1 precipitated a molecule from CTCL cells that, under reducing conditions, has two components with molecular mass of 27,200 and 25,800 D. BE2 also reacted significantly (P less than or equal to 0.001) with CTCL cells from two of four patients (RIA, mean +/- SD = 519 +/- 113 cpm). The binding of BE2 to normal mononuclear cells was indistinguishable from background (309 +/- 38 cpm). BE2 also reacted with an antigen present on EBV-B-cell lines (RIA, mean +/- SD = 654 +/- 194) and MOLT 3 and HUT 78 T-cell lines. BE2 reacted with an antigen expressed on a subpopulation of lymphocytes from five of eight patients with B-cell CLL studied by IIF (mean +/- SD = 18 +/- 6). Other long-term T-cell lines and tumor cell lines studied by IIF were unreactive with BE2. BE2 did not react with any of the normal tissues studied. BE2 precipitated a molecule (78,000 D) from CTCL cells and EBV-B cells with a single component under reducing conditions. Immunoperoxidase-labeled BE1 and BE2 reacted with CTCL cells in frozen sections of infiltrated lymph nodes and skin. In addition, BE1 and BE2 reacted with blood lymphocytes from 16 of 21 patients whose CTCL had otherwise been considered localized to skin. These two monoclonal antibodies react with tumor antigens associated with CTCL and appear to be useful in the diagnosis of this disorder.