Biomedical subjects
Publications and source records attributed to M Krainer.
The present consensus manuscript defines evidence-based recommendations for state-of-the-art treatment of metastatic breast cancer depending on disease-associated and biologic variables.
Five human soft tissue sarcoma (STS) cell lines (HTB-82 rhabdomyosarcoma, HTB-91 fibrosarcoma, HTB-92 liposarcoma, HTB-93 synovial sarcoma and HTB-94 chondrosarcoma) were analysed for their sensitivity to tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and the function of the TRAIL apoptotic pathway in these cells. TRAIL induced significant apoptosis (>90%) in HTB-92 and HTB-93 cells, whereas no effect was observed in HTB-82, HTB-91 and HTB-94 cells. TRAIL-Receptor 1 (TRAIL-R1) was expressed in TRAIL-sensitive HTB-92 and HTB-93 cell lines, but not in TRAIL-resistant HTB-91 and HTB-94 cells. HTB-82 cells, which expressed the long (c-FLIP(L)) and short (c-FLIP(S)) splice variants of the FLICE-like inhibitory protein (FLIP), were resistant to TRAIL in spite of the presence of TRAIL-R1. TRAIL-R2,-R3,-R4 and osteoprotegerin (OPG) expression did not correlate with TRAIL sensitivity. Coincubation of TRAIL and doxorubicin led to the overexpression of TRAIL-R2 resulting in a synergistic effect of doxorubicin and TRAIL in TRAIL-sensitive cell lines and in the overcoming of TRAIL-resistance in all of the TRAIL-resistant cell lines, except HTB-91, which lacked caspase 8 expression. These data suggest that TRAIL, either as a single agent or in combination with cytotoxic agents, might represent a new treatment option for advanced STS, which constitutes a largely chemotherapy-resistant disease.
OBJECTIVES: In previous experiments, we demonstrated a decreased expression of intercellular adhesion molecule I (ICAM-1) on both tumour cells and antigen-presenting cells derived from patients with breast cancer, resulting in an abrogation of antigen presentation and tumour cell lysis. Recently, increased levels of a soluble isoform of ICAM-1 (sICAM-1) have been detected in the sera of breast cancer patients. The present investigation was performed in order to investigate the biological relevance of serum concentrations and the effects of sICAM-1 in patients with breast cancer. PATIENTS AND METHODS: sICAM-1 was determined using a sandwich enzyme immunoassay on sera from 88 patients with various stages of breast cancer and correlated with clinical parameters. The effect of sICAM-1 present in the sera of patients with breast cancer upon unspecific and anti-Her-21/neu antibody-mediated cytotoxicity (ADCC), as well as upon antigen presentation, was determined using a 51Cr-release assay and [3H]thymidine-uptake of T cells after co-incubation with tetanus-toxoid-pulsed antigen-presenting cells. RESULTS: In patients with early breast cancer, serum levels of sICAM-1 were significantly lower compared to patients with metastatic disease, but did not correlate with usual clinical parameters. In patients with metastatic breast cancer, a significant correlation of sICAM-1 with tumour markers CEA and CA 15-3 was observed. No influence of sICAM-1 upon unspecific cytotoxicity, ADCC, or the ability to present antigen was observed. DISCUSSION: The origin of sICAM-1 in the sera of patients with breast cancer remains unknown. In contrast to its membrane-bound isoform, sICAM-1 was increased in the sera of patients with various stages of breast cancer, but its presence did not influence unspecific cytotoxicity, ADCC, or antigen-induced T cell proliferation.
The present study was performed to assess the difference in acceptance of psychosocial counseling and resulting benefits between patients with breast cancer with early or late onset. In a prospective randomized controlled study conducted over 6 months, 41 women with a new diagnosis of early breast cancer (group 1) and 43 patients with advanced breast cancer (group 2) received individually tailored psychosocial support and were compared against controls. This therapy was free of charge, and the duration of support was determined by the patients' wishes and needs. Among the patients with new onset of disease acceptance of the psychosocial counseling was high, and these patients experienced significant improvements in their quality of life. In contrast, acceptance of psychosocial counseling was low in the advanced breast cancer group and the therapy did not improve quality of life over the observation period of 6 months. Early psychosocial support in patients with breast cancer meets with a high acceptance rate and improves quality of life.
Progressive genetic changes such as the inactivation of tumor suppressor genes (TSG) are thought to play an important role in the initiation and progression of ovarian cancer. Frequent nonrandom allelic imbalance (AI) at 8p11-p21 and 8p22-pter suggests the existence of TSGs that may be involved in the carcinogenesis of several human malignancies. We investigated 70 ovarian tumors with 11 highly polymorphic markers spanning 8p12-p21 and 8p22-pter to produce an AI map of 8p in epithelial ovarian cancer. Allelic imbalance was demonstrated in 54 tumors (77%), most frequently occurring at D8S136 (54%) and at D8S1992 (55%). Poorly differentiated and advanced stage cancers were more often affected by AI (G1+G2 vs. G3; 20% vs. 66%; stage I+II vs. III+IV, 36% vs. 54%, P<.001; Kruskal-Wallis test) than well differentiated and early stage tumors. There was no relationship between histological subtype and AI. Smallest regions of overlap (SRO) were delineated by analyzing 38 tumors with partial AI. This study provides compelling evidence for the involvement of TSGs on the short arm of chromosome 8, at 8p12-p21 and at 8p23 in the development and progression of epithelial ovarian cancer.
BACKGROUND: Metastatic soft tissue sarcoma not amenable to curative surgery has a dismal prognosis. Aggressive treatment with anthracyclines and ifosfamide represents the current therapeutic mainstay in these patients, most of whom succumb to relapses. Thus, the efficacy of subsequent therapeutic approaches has to be weighed against toxicity caused by palliative treatment. PATIENTS AND METHODS: Patients with locally advanced or metastatic soft tissue sarcoma refractory to treatment with anthracyclines and ifosfamide were enrolled into the present phase II study. Patients were assigned to receive docetaxel at 100 mg/m2 every three weeks. In case of severe toxicity, patients were switched to a weekly schedule of docetaxel (40 mg/m2). RESULTS: A total of 106 cycles (80% at the scheduled 100 mg/m2 dose level) were administered in 27 patients. Partial response was observed in 4 (15%) patients and 4 (15%) patients experienced disease stabilization. Median progression free survival and overall survival were 2.4 (range: 0.9-23.9) and 7.7 (range: 1.0-44.3) months, respectively. Upon renewed progression, three patients initially responsive to treatment with docetaxel were successfully reinduced by treatment with docetaxel. The safety profile of docetaxel was tolerable and the administration mostly manageable on an outpatient basis. CONCLUSIONS: Our results suggest that docetaxel represents an efficacious and tolerable treatment in a minority of patients refractory to standard treatment. There is a need for better identification of patients most likely to benefit from salvage treatment with docetaxel.
OBJECTIVES: To investigate the impact of polychemotherapy on cellular immunity in patients with testicular cancer. METHODS: Lymphocyte subpopulations, lymphoproliferative responses to mitogenic stimulation, and mitogen-induced release of soluble interleukin-2 receptor from peripheral blood mononuclear cells were investigated in 15 patients with testicular germ cell tumors a median of 61 months (range 7 to 73) after polychemotherapy with bleomycin, etoposide, and cisplatin (BEP). RESULTS: The numbers of peripheral blood T cells (CD3+), CD4+ and CD8+ subsets, and lymphoproliferative responses to pokeweed mitogen, phytohemagglutinin, and concanavalin A in patients were comparable to those of healthy control subjects. When two groups of patients were formed according to elapsed time from BEP polychemotherapy and study onset (group A, 12 months and group B, 69 months after termination of BEP), a significant increase in lymphoproliferative response to concanavalin A (P <0.05) was found in group A 1 year after chemotherapy. CONCLUSIONS: BEP chemotherapy administered to patients with testicular cancer does not result in impairment of cellular immunity but rather leads to a significant increase in the capacity of patients' lymphocytes to respond to mitogenic stimulation up to 1 year after polychemotherapy. Moreover, the increased T-cell activity found after BEP therapy may contribute to the high rate of long-term complete remission.
RAD51, RAD52, and RAD54 encode proteins that are critical to the repair of double-strand DNA breaks by homologous recombination. The physical interactions among the products of RAD51, BRCA1, and BRCA2 have suggested that the BRCA1 and BRCA2 breast cancer susceptibility genes may function, at least in part, in this DNA damage repair pathway. Given the observation that different genes within a common functional pathway may be targeted by mutations in human cancers, we analyzed RAD51, RAD52, and RAD54 for the presence of germ-line mutations in 100 cases with early-onset breast cancer and for somatic mutations in 15 human breast cancer cell lines. Two premature stop codons, Ser346ter and Tyr415ter, were identified in germ-line RAD52 alleles from 5% of early-onset breast cancer cases. Together, these two heterozygous mutations were also found in 8% of a healthy control population, indicating that they do not confer an increased risk for breast cancer. A rare germ-line missense mutation was identified in RAD54, whereas no sequence variants were found in RAD51. None of the three RAD genes demonstrated somatic mutations in breast cancer cell lines. We conclude that, despite their potential functional association with the BRCA gene products, RAD51, RAD52, and RAD54 are not themselves targeted by mutations in human breast cancer. The presence of common nonsense mutations in RAD52 within the population may have significance for other conditions associated with potential alterations in DNA damage repair pathways.
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) is widely used in the treatment or prevention of neutropenia induced by cytostatic regimens. Recent studies with this cytokine have shown several local and/or systemic side effects. We herein report on four patients with different tumor entities receiving GM-CSF as a part of their intensified cytostatic regimen. All four patients developed immune phenomena (sicca syndrome, seropositive arthralgia, hyperthyroidism, and pneumonitis, respectively) during or after subcutaneous treatment with GM-CSF. Pathologic alterations in immunologic serum parameters as well as histopathologic findings accompanied the clinical symptoms. These observations suggest that the therapeutic application of GM-CSF might be involved in the clinical emergence of autoimmune diseases.
BACKGROUND: Cardiovascular toxicity of chemotherapy for testicular cancer is a matter of discussion, since highly efficient agents can achieve cure of the disease, even in the metastasized setting. Acute ischemic events during the treatment period and a persistently elevated serum cholesterol thereafter are observations of particular concern in these patients, and the underlying basic mechanisms are unknown to date. OBJECTIVE: To evaluate etoposide, which is part of the standard treatment for testicular cancer, as a potential cause of atherogenesis in an experimental model. SETTING: Aortic 125I-labeled low-density lipoprotein retention was studied in 72 cholesterol-fed rabbits under etoposide treatment and was quantified according to the morphologically assessed type of surface lining. Aortic cholesterol content was determined both by Sudan III staining and quantitatively by a biochemical assay. RESULTS: A reduced uptake of 125I-labeled low-density lipoprotein in the arterial wall was observed in the etoposide-treated animals, which resulted in a size reduction of sudanophilic areas and cholesterol content. Whereas the breakdown of 125I-labeled low-density lipoprotein in the liver was not significantly enhanced, the plasma decay of 125I-labeled low-density lipoprotein was faster and serum cholesterol was lower in the etoposide group than in controls. CONCLUSION: Unexpectedly, we found an improvement of arterial wall lipid metabolism under etoposide treatment and can thus exclude this substance as a promoter of atherogenesis in this model.
X-linked lymphoproliferative syndrome (XLP) is an inherited immunodeficiency characterized by increased susceptibility to Epstein-Barr virus (EBV). In affected males, primary EBV infection leads to the uncontrolled proliferation of virus-containing B cells and reactive cytotoxic T cells, often culminating in the development of high-grade lymphoma. The XLP gene has been mapped to chromosome band Xq25 through linkage analysis and the discovery of patients harboring large constitutional genomic deletions. We describe here the presence of small deletions and intragenic mutations that specifically disrupt a gene named DSHP in 6 of 10 unrelated patients with XLP. This gene encodes a predicted protein of 128 amino acids composing a single SH2 domain with extensive homology to the SH2 domain of SHIP, an inositol polyphosphate 5-phosphatase that functions as a negative regulator of lymphocyte activation. DSHP is expressed in transformed T cell lines and is induced following in vitro activation of peripheral blood T lymphocytes. Expression of DSHP is restricted in vivo to lymphoid tissues, and RNA in situ hybridization demonstrates DSHP expression in activated T and B cell regions of reactive lymph nodes and in both T and B cell neoplasms. These observations confirm the identity of DSHP as the gene responsible for XLP, and suggest a role in the regulation of lymphocyte activation and proliferation. Induction of DSHP may sustain the immune response by interfering with SHIP-mediated inhibition of lymphocyte activation, while its inactivation in XLP patients results in a selective immunodeficiency to EBV.
A randomised phase II/III study was conducted in patients with advanced breast cancer to determine the dose intensity achievable through an acceleration of administration of chemotherapy with epidoxorubicin and cyclophosphamide (EC) alone, as compared with the combination of this regimen with two different schedules of granulocyte-macrophage colony stimulating factor (GM-CSF). 73 patients received EC intravenous (i.v.) (epidoxorubicin 100 mg/m2, cyclophosphamide 600 mg/m2) on day 1 (group A), or the same chemotherapy plus sub-cutaneous (s.c.) GM-CSF (5 micrograms/kg/day) either from days 3 to 12 (group B) or from days -6 to -3 (group C). The primary objective of the study was the investigation of dose intensity delivered in the three treatment arms, whereas the secondary objective was response rate. A significant increase (P = 0.006) in dose intensity of 21% was observed for treatment group B, whereas the increase in dose intensity achieved in group C (7%) was not significant (P = 0.086). Response rates (complete response (CR) + partial response (PR)) of 56% were observed in group A, 65% in group B, and 57% in group C, respectively. This difference in response rates did not reach statistical significance (P = 0.271). We thus conclude that an acceleration of the EC regimen over the standard schedule could be accomplished with postchemotherapeutic GM-CSF support, leading to an increase in dose intensity, whereas pretherapeutic short-term GM-CSF administration did not reach this goal.
Amplification and over-expression of the HER-2/neu proto-oncogene are associated with poor prognosis in women with both node-positive and node-negative breast cancer. Therefore, the encoded surface glycoprotein represents an attractive target for cancer immunotherapies. Furthermore, the extracellular domain of HER-2/neu is released from the cell surface by proteolytic cleavage. In the present experiments, we investigated the potential biologic effects of soluble HER-2/neu with particular emphasis on its interaction with anti-HER-2/neu antibodies. A monoclonal antibody specific for the extracellular domain of HER-2/neu dose dependently inhibited the proliferation of highly HER-2/neu-expressing SK-BR-3 and BT-474 breast cancer cells but had no effect on the proliferation of weakly to moderately HER-2/neu-expressing MCF-7, HBL-100 and ZR-75-1 breast cells. Addition of SK-BR-3 or BT-474 cell supernatants with high concentrations of soluble HER-2/neu led to a neutralization of anti-HER-2/neu antibody-mediated inhibition of proliferation due to a binding of soluble HER-2/neu by the antibody, which could be demonstrated by immunoprecipitation. Furthermore, the ability of anti-HER-2/neu antibodies to mediate antibody-dependent cellular cytotoxicity (ADCC) by lymphokine-activated killer cells was assessed. Cytolysis of SK-BR-3 tumor cells was increased significantly in the presence of anti-HER-2/neu antibodies. Similar to the proliferation inhibition, ADCC was neutralized by addition of soluble HER-2/neu-containing supernatants. Our data suggest that tumors rich in HER-2/neu might thus escape certain steps of immunologic control by neutralizing biologic activities of anti HER-2/neu antibodies due to the presence of soluble HER-2/neu.
In order to study adhesion-molecule expression and its consequences for cellular recognition, the presence of adhesion molecules ICAM-1, VCAM-1, VLA-4, LFA-1, alpha, LFA-1 beta, LFA-3, beta1-integrin and beta3-integrin was studied on specimens from breast tissue by immunohistochemistry and on cells from breast cell lines propagated in vitro. Breast-cancer tissue and the breast-cancer cell lines MCF-7, SK-BR-3 and ZR-75-1 showed expression of ICAM-1 and VLA-4 significantly lower than that of benign breast cells or normal breast epithelium. Of various cytokines tested, including recombinant human (rh) interleukin-6 (IL-6), rh tumor necrosis factor alpha (TNF-alpha), interleukin 2 (IL-2), granulocyte/macrophage-colony-stimulating-factor (GM-CSF), interferon-alpha (IFN-alpha) and interferon-gamma (IFN-gamma), only TNF was able to re-induce expression of ICAM-1 on cells from MCF-7, SK-BR-3 and ZR-75-1. Further, the ability of either unstimulated or lymphokine-stimulated killer (LAK) cells to recognize and lyse native or TNF-stimulated breast-cancer cells was studied. Whereas neither unstimulated lymphocytes or LAK cells were able to lyse untreated breast-cancer cells deficient for ICAM-1 expression, pre-treatment of tumor cells with TNF led to increased tumor-cell lysis. Anti-ICAM-1 antibodies, and pre-treatment of tumor cells with anti-TNF-receptor antibodies, abrogated these findings, corroborating their specificity. We thus conclude that the defective expression of ICAM-1 in our model might constitute a mechanism by which breast-cancer cells escape immunologic recognition and lysis by appropriate effector cells.
BACKGROUND: Germ-line mutations in the BRCA1 and BRCA2 genes predispose women to breast cancer. BRCA1 mutations are found in approximately 12 percent of women with breast cancer of early onset, and the specific mutation causing a deletion of adenine and guanine (185delAG), which is present in 1 percent of the Ashkenazi Jewish population, contributes to 21 percent of breast cancers among young Jewish women. The contribution of BRCA2 mutations to breast cancer of early onset is unknown. METHODS: Lymphocyte specimens from 73 women with breast cancer diagnosed by the age of 32 were studied for heterozygous mutations of BRCA2 by a complementary-DNA-based protein-truncation assay, followed by automated nucleotide sequencing. In addition, specimens from 39 Jewish women with breast cancer diagnosed by the age of 40 were tested for specific mutations by an allele-specific polymerase chain reaction. RESULTS: Definite BRCA2 mutations were found in 2 of the 73 women with early-onset breast cancer (2.7 percent; 95 percent confidence interval, 0.4 to 9.6 percent), suggesting that BRCA2 is associated with fewer cases than BRCA1 (P=0.03). The specific BRCA2 mutation causing a deletion of thymine (6174delT), which is found in 1.3 percent of the Ashkenazi Jewish population, was observed in 1 of the 39 young Jewish women with breast cancer (2.6 percent; 95 percent confidence interval, 0.09 to 13.5 percent), indicating that it has a small role as a risk factor for early-onset breast cancer. Among young women with breast cancer, there are BRCA2 mutations that cause truncation of the extreme C terminus of the protein and that may be functionally silent, along with definite truncating mutations. CONCLUSIONS: Germ-line mutations in BRCA2 contribute to fewer cases of breast cancer among young women than do mutations in BRCA1. Carriers of BRCA2 mutations may have a smaller increase in the risk of early-onset breast cancer.
The detection of inactivating mutations in tumor suppressor genes is critical to their characterization, as well as to the development of diagnostic testing. Most approaches for mutational screening of germ-line specimens are complicated by the fact that mutations are heterozygous and that missense mutations are difficult to interpret in the absence of information about protein function. We describe a novel method using Saccharomyces cerevisiae for detecting protein-truncating mutations in any gene of interest. The PCR-amplified coding sequence is inserted by homologous recombination into a yeast URA3 fusion protein, and transformants are assayed for growth in the absence of uracil. The high efficiency of homologous recombination in yeast ensures that both alleles are represented among transformants and achieves separation of alleles, which facilitates subsequent nucleotide sequencing of the mutated transcript. The specificity of translational initiation of the URA3 gene leads to minimal enzymatic activity in transformants harboring an inserted stop codon, and hence to reliable distinction between specimens with wild-type alleles and those with a heterozygous truncating mutation. This yeast-based stop codon assay accurately detects heterozygous truncating mutations in the BRCA1 gene in patients with early onset of breast cancer and in the APC gene in patients with familial adenomatous polyposis. This approach offers a rapid and reliable method for genetic diagnosis in individuals at high risk for germ-line mutations in cancer susceptibility genes.
BACKGROUND: Mutations in a germ-line allele of the BRCA1 gene contribute to the familial breast cancer syndrome. However, the prevalence of these mutations is unknown in women with breast cancer who do not have the features of this familial syndrome. We sought BRCA1 mutations in women who were given a diagnosis of breast cancer at an early age, because early onset is characteristic of a genetic predisposition to cancer. METHODS: Clinical information and peripheral-blood mononuclear cells were obtained from 418 women from the Boston metropolitan area in whom breast cancer was diagnosed at or before the age of 40. A comprehensive BRCA1 mutational analysis, involving automated nucleotide sequencing and a protein-truncation assay, was undertaken in 30 of these women, who had breast cancer before the age of 30. In addition, the BRCA1 mutation 185delAG, which is prevalent in the Ashkenazi Jewish population, was sought with an allele-specific polymerase-chain-reaction assay in 39 Jewish women among the 418 women who had breast cancer at or before the age of 40. RESULTS: Among 30 women with breast cancer before the age of 30, 4 (13 percent) had definite, chain-terminating mutations and 1 had a missense mutation. Two of the four Jewish women in this cohort had the 185delAG mutation. Among the 39 Jewish women with breast cancer at or before the age of 40, 8 (21 percent) carried the 185delAG mutation (95 percent confidence interval, 9 to 36 percent). CONCLUSIONS: Germ-line BRCA1 mutations can be present in young women with breast cancer who do not belong to families with multiple affected members. The specific BRCA1 mutation known as 185delAG is strongly associated with the onset of breast cancer in Jewish women before the age of 40.
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