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R C Bast

Publications and source records attributed to R C Bast.

At least 181 records · Page 10Linked to original sources
PubMed1990

Expression of epidermal growth factor receptor and HER-2/neu in normal and neoplastic cervix, vulva, and vagina.

Monoclonal antibodies were used to localize immunohistochemically epidermal growth factor receptor and HER-2/neu in normal and neoplastic frozen tissue samples from the lower genital tract of women. In squamous epithelia of the cervix, vulva, and vagina, epidermal growth factor receptor and HER-2/neu both were expressed most strongly by basal keratinocytes. Expression of both of these cell surface molecules decreased as cells underwent differentiation toward the mucosal surface. In contrast, both epidermal growth factor receptor and HER-2/neu were expressed throughout the entire thickness of the epithelium by undifferentiated squamous cells in squamous metaplasia, raised condyloma, and carcinoma in situ. In 34 squamous cancers of the cervix, vulva, and vagina, all malignant cells were found to have moderate to heavy staining for epidermal growth factor receptor. Staining of 33 of these cancers for HER-2/neu was light, although one patient who presented with distant metastases had heavy staining for HER-2/neu. These data suggest that although overexpression of HER-2/neu in squamous cancers of the lower genital tract is a rare event, it may be associated with aggressive biologic behavior.

Adenocarcinoma↗
PubMed1990

Preoperative serum tumor-associated antigen levels in women with pelvic masses.

Preoperative sera were assayed for tumor-associated antigens CA 125, TAG 72, and CA 15-3 in 100 women with pelvic masses. Serum CA 125 levels were elevated above 65 U/mL in 83% of 42 patients with ovarian malignancies, in 58% of 12 patients with nonovarian malignancies, and in 17% of 46 patients with benign pelvic masses. Elevations of TAG 72 and CA 15-3 levels occurred less frequently in all groups of patients. Serum CA 125 levels distinguished most effectively between patients with malignant pelvic masses and those with benign pelvic masses, having a sensitivity of 78% and a specificity of 83% at a threshold level of 65 U/mL. When comparing 33 patients with epithelial ovarian carcinomas to 46 patients with benign masses, the CA 125 level alone yielded a sensitivity of 88% with a specificity of 83%. Coordinate elevations of CA 125 (above 65 U/mL) and TAG 72 (above 10 U/mL) or CA 15-3 (above 30 U/mL) distinguished ovarian epithelial carcinomas from benign masses with a sensitivity of 73% and a specificity of 98%, which improved to 81 and 100%, respectively, among patients over 50 years of age. Given the marked increase in specificity observed with this panel of three serum tumor-associated antigens, use of multiple markers might facilitate screening for ovarian carcinoma and appropriate referral of patients with pelvic masses for cytoreductive operations.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1990

The role of peptide growth factors in epithelial ovarian cancer.

We studied the effect of epidermal growth factor, platelet-derived growth factor, fibroblast growth factor, and transforming growth factor-beta on proliferation of four epithelial ovarian cancer cell lines (OVCA 420, OVCA 429, OVCA 432, and OVCA 433). Epidermal growth factor stimulated growth of OVCA 429 cells (P = .0001) and OVCA 433 cells (P = .0002). Platelet-derived growth factor did not stimulate growth of any of the cell lines. Fibroblast growth factor stimulated growth of OVCA 420 cells (P = .003). Transforming growth factor-beta inhibited growth of OVCA 420 cells (P = .0001), OVCA 432 cells (P = .003), and OVCA 433 cells (P = .004). To detect production of known growth factors by the cancer cell lines, we tested the effect of cancer cell-conditioned media on proliferation of cell lines known to respond to growth factors. Only media exposed to OVCA 433 cells were found to contain activity that mimicked one of the known growth factors (transforming growth factor-beta). These results suggest that individual ovarian cancers vary widely in their response to and production of known peptide growth factors. Finally, we found that OVCA 429-conditioned medium significantly inhibited proliferation of mitogen-stimulated lymphocytes (P less than .0001). The characteristics of this immunosuppressive factor were distinct from those of transforming growth factor-beta. Production of this factor by an immortalized cell line provides a unique opportunity to identify an immunosuppressive substance associated with ovarian cancer.

Cell Division↗
PubMed1989

Elimination of malignant clonogenic breast cancer cells from human bone marrow.

Autologous bone marrow transplantation is a promising approach to the treatment of breast cancer but is at present limited to patients without bone marrow metastases. To eliminate malignant clonogenic breast cancer cells from normal human bone marrow, immunomagnetic separation has been combined with chemoseparation using 4-hydroperoxycyclophosphamide. Breast cancer cell lines have been mixed with a 10-fold excess of irradiated human bone marrow from normal donors. Mixtures have been incubated with a combination of five different monoclonal antibodies which bind to epithelial cell surface antigens of Mr 42,000, 55,000, 72,000, 200,000, and greater than 200,000. Antiglobulin coated microspheres which contained magnetite were added, and tumor cells were trapped in a magnetic field. Elimination of tumor cells from the decanted marrow was measured in a limiting dilution assay. Two treatments with antibody and microspheres permitted elimination of 2-4 logs of clonogenic breast cancer cells, depending upon the cell line studied. Similar treatment of nonirradiated normal marrow failed to affect levels of colony forming units-granulocyte-macrophage significantly. Use of immunomagnetic purging in combination with 4-hydroperoxycyclophosphamide eliminated up to 5 logs of tumor cells but reduced the recovery of colony forming units-granulocyte-macrophage. If prompt engraftment is observed following reinfusion of similarly treated marrow in phase I trials, these techniques should permit extension of autologous bone marrow transplantation to a larger population of breast cancer patients.

Antibodies, Monoclonal↗
PubMed1989

Differential induction by interferons of major histocompatibility complex-encoded and non-major histocompatibility complex-encoded antigens in human breast and ovarian carcinoma cell lines.

Treatment of cancer cells with interferons can modulate expression of cell surface antigens, particularly those of the major histocompatibility complex (MHC). To examine the effect of recombinant gamma- and alpha-interferons on expression of non-MHC antigens, murine monoclonal antibodies have been used to quantitate 14 distinct tumor-associated cell surface antigens from five breast cancer cell lines and five ovarian cancer cell lines using a live cell radioimmunoassay. Both Class I and Class II MHC antigens could be augmented or induced with gamma-interferon. Significantly increased expression of MHC antigens was observed in nine of 10 cell lines with induction indices as high as 11-fold. When 17 non-MHC epitopes were measured on 10 cell lines, minimal (1.3-2.7-fold) induction was observed in 10 of the 170 instances evaluated. Expression of only two epitopes, 2G3 and 735B11, was increased on more than one cell line. On six cell lines expression of non-MHC epitopes could not be increased. Consequently, among many different cell surface determinants, interferons produced a highly selective augmentation or induction of MHC antigens, whereas augmentation or induction of other tumor-associated antigens was apparently restricted to a few epitopes.

Antigens, Neoplasm↗
PubMed1989

Immunohistochemical expression of CA 125 in endometrial adenocarcinoma: correlation of antigen expression with metastatic potential.

Immunohistochemical localization of CA 125 using murine monoclonal antibody OC 125 was performed on fresh frozen tissue from 44 endometrial adenocarcinomas and 26 benign endometria. Immunohistochemical evaluation incorporated both intensity and distribution of staining (CA 125 HSCORE). Thirty-seven cancers (84%) and 23 benign endometria (88%) expressed immunohistochemically detectable CA 125. Staining was confined to epithelial cells and was present both on the cell membrane and in the cytoplasm. Among the 44 endometrial cancers, CA 125 HSCORE did not correlate with histological grade, depth of myometrial invasion or estrogen/progesterone receptor levels. Following surgical staging, 13 patients (30%) were found to have extrauterine metastatic disease. The median CA 125 HSCORE of patients with metastatic disease (2.25) was significantly higher than that of patients with disease confined to the uterus (0.6) (P less than 0.001). In addition, high CA 125 HSCORE also correlated with the presence of lymph node metastasis (P less than 0.001). The results of this study suggest that high CA 125 expression by endometrial adenocarcinomas is associated with increased metastatic potential.

Adenocarcinoma↗
PubMed1989

Heterogeneity of antigen expression in benign and malignant breast and ovarian epithelial cells.

Expression of II distinct antigen families has been studied in normal and malignant epithelial cells from breast and ovary by avidin-biotin immunoperoxidase staining of frozen tissue sections. Each of the antigens was expressed in a fraction of the normal and malignant breast tissues from different individuals. Among breast and ovarian cancers, a similar fraction of tumors expressed each of the determinants. An epitope on a 42-kDa glycoprotein was expressed significantly more often by ovarian carcinomas than by benign ovarian epithelium. Several determinants on 66-, 240-kDa or high-molecular-weight proteins or glycoproteins were expressed significantly more often on benign breast epithelium than on normal ovarian epithelium. Substantial heterogeneity in antigen expression was observed among different tumor specimens. Each of 14 epithelial ovarian cancers expressed a distinctive combination of antigens. Among 18 breast cancers, 16 distinct antigenic phenotypes were observed. Interestingly, comparable heterogeneity was observed in the expression of epitopes on benign breast and ovarian epithelium, compatible with the possibility that the monoclonal reagents recognized polymorphic determinants. Substantial variations in antigen expression were also observed among cells within each neoplasm. However, when antibodies against 5 different determinants were used in combination, a majority of cells could be stained intensely in all 13 breast carcinomas tested and more than 95% of tumor cells could be stained in 10 of the 13.

Antigens, Neoplasm↗
PubMed1989

High-dose combination cyclophosphamide, cisplatin, and melphalan with autologous bone marrow support. A clinical and pharmacologic study.

A total of 23 patients were treated at five dose escalations with high-dose combination cyclophosphamide, cisplatin, and melphalan with autologous bone marrow support. The maximum tolerated doses of cyclophosphamide, cisplatin, and melphalan were 5,625, 180, and 80 mg/m2, respectively. The dose-limiting toxicity was cardiac toxicity. Objective tumor regression occurred in 14 of 18 evaluable cases, with a median duration of 3.5 months. Pharmacokinetic evaluation of melphalan in 20 patients revealed a dose-related increase in maximum plasma concentration (Cmax) and area under the curve (AUC). Perturbation of the melphalan plasma half-life and AUC, associated with severe toxicity, resulted when renal insufficiency occurred. The results suggest that high-dose combination cyclophosphamide, cisplatin, and melphalan produces frequent, rapid responses in breast cancer, melanoma, and sarcoma, although with significant extramedullary toxicity. The pharmacokinetics suggest that modification of the treatment schedule may result in a reduction of treatment-related toxicity.

Adult↗
PubMed1989

CA 125 levels in patients with ovarian carcinoma undergoing autologous bone marrow transplantation.

Levels of CA 125, determined in three patients with ovarian carcinoma undergoing autologous bone marrow transplantation, dropped significantly in the month after bone marrow transplantation. This decrease was linear by multiple regression analysis. The CA 125 decrease after bone marrow transplantation in patients with nonevaluable or stable disease may represent biologic response to high-dose therapy.

Adult↗
PubMed1989

Epidermal growth factor receptor expression in normal and malignant endometrium.

Epidermal growth factor receptor expression in fresh-frozen uterine tissues was studied with the use of monoclonal antibody 528, which recognizes an epitope on the external domain of the epidermal growth factor receptor. Immunohistochemically detectable epidermal growth factor receptor was seen in all uterine cell types in 19 of 20 normal uteri. Staining of endometrial glands and endometrial stromal cells was consistently greater than that of myometrium, and no variation in intensity or distribution of staining was seen during the menstrual cycle. Immunohistochemically detectable epidermal growth factor receptor was found less frequently in endometrial adenocarcinomas than in normal endometrium (p less than 0.01). Thirteen of 40 endometrial adenocarcinomas (32.5%) did not express detectable receptor. Epidermal growth factor receptor expression did not correlate with histologic grade, depth of myometrial invasion, estrogen-progesterone receptor status, the presence of extrauterine metastases, or the development of recurrent disease.

Adenocarcinoma↗
PubMed1989

Immunohistochemical expression of TAG-72 in normal and malignant endometrium: correlation of antigen expression with estrogen receptor and progesterone receptor levels.

TAG-72 is a tumor-associated antigen that is expressed by secretory endometrium and most endometrial adenocarcinomas. We used immunohistochemical techniques to quantitate expression of TAG-72, estrogen receptor, and progesterone receptor in 21 normal endometria and 44 endometrial adenocarcinomas. In normal cycling endometrial glands, TAG-72 expression was related inversely to expression of receptors for estrogen and progesterone. This suggests that TAG-72 expression in normal endometrium may be hormonally regulated. Ninety-one percent of endometrial adenocarcinomas expressed immunohistochemically detectable TAG-72. The magnitude of TAG-72 expression did not correlate with other known prognostic factors in endometrial cancer such as histologic grade, depth of myometrial invasion, surgical stage, or steroid receptor status. The production of TAG-72 by most endometrial adenocarcinomas may represent nonspecific expression by cells that have dedifferentiated.

Adult↗
PubMed1989

Pharmacokinetics of a radioiodinated monoclonal antibody F(ab')2 fragment in a xenograft model with circulating antigen.

The pharmacokinetics of 131I-labeled OC 125 F(ab')2 antibody fragment were investigated in athymic mice bearing OVCAR-3 ovarian carcinoma xenografts, a model in which the CA 125 antigen is present in serum. Nine antibody doses between 0.1 and 650 micrograms were studied. Optimal tumor to normal tissue ratios were obtained at 100-200 micrograms of F(ab')2. At most antibody doses, the pre-injection level of circulating CA 125 appeared to influence the localization of 131I activity in tumor, liver and spleen.

Animals↗
PubMed1989

The CA 125 tumour-associated antigen: a review of the literature.

CA 125 is an antigenic determinant on a high-molecular-weight glycoprotein recognized by a monoclonal antibody which was raised using an ovarian cancer cell line as an immunogen. During the last 5 years the studies reviewed in this paper have provided information concerning the nature, distribution and clinical significance of CA 125. The CA 125 determinant is expressed by epithelial ovarian tumours and various other pathological and normal tissues of Müllerian origin. The function of the glycoprotein expressing CA 125 remains unclear but the distribution of the antigen suggests that it may have a physiological role. The highest serum levels of CA 125 are found in ovarian cancer patients, but elevation of serum CA 125 may also be associated with other malignancies and benign and physiological states, including pregnancy, endometriosis and menstruation. Despite limitations of sensitivity and specificity serum CA 125 estimation is of clinical value in the pre-operative diagnosis and monitoring of ovarian malignancy and may be a prognostic indicator for this disease. The role of CA 125 in screening for early-stage ovarian cancer is currently under investigation. Recent reports suggest that serum CA 125 measurement may also be of value as a prognostic indicator in endometrial cancer and as a reflection of disease status in advanced endometriosis.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1989

Constitutive production of macrophage colony-stimulating factor by human ovarian and breast cancer cell lines.

Many nonhematologic tumors produce growth factors that may influence cellular proliferation either by autocrine or by paracrine mechanisms. In the current study, human tumor cell lines were investigated for the constitutive production of macrophage colony-stimulating factor (M-CSF). Culture supernatants obtained from cell lines were analyzed using a radioimmunoassay and a radioreceptor assay specific for M-CSF. Among the various cell types analyzed, all the ovarian cell lines and a majority of the breast cancer cell lines secreted significant amount of an M-CSF-like factor. Treatment of mouse bone marrow cultures with culture supernatants from ovarian cancer cells stimulated the production of macrophage colonies. Analysis of total cellular RNA obtained from the ovarian cell lines by Northern blot showed multiple sizes of M-CSF transcripts with an abundance of a 4.2-kb message. The relative amount of M-CSF transcripts correlated with the level of immunoreactive material seen in the culture supernatants.

Animals↗
PubMed1989

Autologous bone marrow transplantation for acute lymphoblastic leukemia.

Forty-four children with acute lymphoblastic leukemia (ALL) who had relapsed (N = 43) or had refractory disease (N = 1) were intensively treated with combination chemotherapy, had remission bone marrow (BM) harvested and purged in vitro with monoclonal antibodies specific for leukemia-associated antigens, underwent postharvest ablative chemotherapy and radiotherapy and subsequently were infused with their autologous marrow. Of the 44 patients treated between November 1980 and January 1988, 19 relapsed, 10 died of complications, and 15 remained in complete remission for a median of 28.5 months (range, 10+ to 94+). Event-free survival (EFS) (+/- SE) at 5 years after autologous transplantation was 29 +/- 8%. For the 26 patients whose initial remission was greater than 2 years, event-free survival was 51 +/- 10%. These results compare favorably with allogeneic transplantation and chemotherapy trials for patients with relapsed ALL, and provide an alternative transplantation option for children without histocompatible donors.

Adolescent↗
PubMed1989

CA 125 assay used in conjunction with CA 15-3 and TAG-72 assays for discrimination between malignant and non-malignant diseases of the ovary.

It has previously been suggested by the authors that elevated serum CA 125 levels may be of value in discriminating malignant from non-malignant pathologies among women with pelvic masses. Enhancement of this discrimination capacity might be achieved by utilizing additional serum assays. To test this hypothesis CA 125, CA 15-3 and TAG-72 levels were determined in double-blind fashion on 219 sera from patients undergoing diagnostic laparotomy for pelvic masses at six gynecological departments in the Stockholm area. Patient diagnoses were verified by chart review. Of the 219 patients, 27 (12%) had non-mucinous ovarian carcinoma, of whom 26 (96%) had CA 125 levels of 35 U/ml or greater 23 (85%) had levels in excess of 65 U/ml. Of 27 patients with mucinous or borderline ovarian carcinoma and patients with other malignancies 18 (67%) had CA 125 levels greater than 35 U/ml. Of 165 women with non-malignant diagnoses 26 (16%) had CA 125 levels in excess of 35 U/ml and 8 (5%) greater than 65 U/ml. Using reference values of 35 U/ml, 30 U/ml and 10 U/ml for the CA 125, CA 15-3 and TAG-72 assay respectively, only 3 of 165 (2%) of non-malignant patients were categorized as positive, compared to 23 of 27 (85%) of those with non-mucinous ovarian carcinoma. Moreover, an analysis of postmenopausal women revealed that the combination of assays--in a model controlling for the effect of CA 125--increased the specificity for diagnosis of benign diseases in women with pelvic masses.

Antigens, Neoplasm↗