Minimal residual disease in autologous hematopoietic harvests from breast cancer patients

The increasing use of high-dose chemotherapy with autologous hematopoietic transplantation for the treatment of solid malignancies has raised concern about the role of tumor cells contaminating the grafts. Minimal residual disease (MRD) in autologous grafts has became a dynamic and intensively studied field in oncology. This review discusses the current status of MRD in breast cancer autografts and presents existing data on detection methodology, clinical relevance, biologic characteristics and purging techniques.     

Polypeptides controlling hematopoietic blood cell development and activation

Summary Colony-stimulating factors (CSFs) have entered the clinical arena. Several investigators have explored, in first clinical phase I studies, different routes of administration to define the optimum biological dose, maximum tolerated dose, toxicity, and pharmacokinetics of these reagents. It has been demonstrated that recombinant human (rh) granulocyte-macrophage CSF (GM-CSF) and granulocyte CSF (G-CSF) can be safely administered over a broad dose range to increase number of circulating granulocytes in man. More recently, GM-CSF and G-CSF have been involved in phase Ib/II studies to assess the granulopoietic responses of patients with granulocytopenia due to various underlying disease states including myelodysplastic syndrome, aplastic anemia, cyclic neutropenia, Kostmann's syndrome, and the acquired immuno-deficiency syndrome. Both factors were also investigated with respect to their potential to prevent chemotherapy induced granulocytopenia or to accelerate recovery from that condition. The short-term effects of rh GM-CSF after autologous bone marrow transplantation for various solid tumors and lymphoid malignancies were assessed as well. In this article we will focus on recent results that have emerged from in vivo studies utilizing CSFs.     

A phase-I clinical study of autologous tumor cells plus interleukin-2-gene-transfected allogeneic fibroblasts as a vaccine in patients with cancer

Tumor cells transfected to express immunostimulatory cytokines, or admixed with similarly modified bystander cells, are able to induce immune responses against unmodified tumor cells in animal models. For treatment of human patients, a vaccine composed of autologous tumor cells and IL-2-secreting allogeneic fibroblasts was developed. Autologous tumor cells were isolated from biopsy specimens. A clone (KMST6.14) of an immortalized human fibroblast line that stably secreted 5290 IU IL-2 per 10⁶ cells and per 24 hr was obtained by cationic lipofection with an expression construct for human IL-2 and Neo^r. Fifteen patients with refractory malignant tumors received 3–4 injections of irradiated KMST6.14 and autologous tumor cells in a phase-I clinical trial. Increasing transient inflammatory responses without systemic toxicity developed at vaccination sites and after injections with irradiated tumor cells only (p < 0.05). These sites contained a dense infiltrate of CD3⁺ T cells with numbers of CD4⁺ helper cells exceeding those of CD8⁺ cytotoxic T cells (CTL). CD8⁺ T-cell lines isolated from vaccination sites of 2 malignant melanoma patients but not of renal-cell carcinoma patients exhibited a dominant lytic activity against autologous tumor cells in vitro. CD8⁺ T-cell clones established from the vaccination site of 1 of 2 renal-cell carcinoma patients preferentially lysed autologous and partially matched allogeneic renal-cell carcinoma cells. In conclusion, a vaccine composed of IL-2 gene-transfected allogeneic fibroblasts and autologous tumor cells is able to enhance specific anti-tumor T-cell responses in vivo without major side-effects. Malignant melanoma and renal-cell carcinoma appear to be promising entities for testing of similar approaches in future therapeutic trials. Int. J. Cancer, 70:269–277, 1997. © 1997 Wiley-Liss, Inc.     

Production of and in vitro response to interleukin 2 in the acquired immunodeficiency syndrome.

To test the hypothesis that deficient interleukin 2 (IL-2) secretion may underlie the impaired capacity of T cells from patients with Acquired Immunodeficiency Syndrome (AIDS) and the AIDS-related complex (ARC) to generate the macrophage-activating lymphokine, gamma interferon (IFN-gamma), we used five specific microbial antigens to examine IL-2 production. Mononuclear cells from only one of 32 (3%) AIDS patients secreted normal levels of IL-2, and 21 (66%) failed to produce any detectable IL-2. For 36 ARC patients, IL-2 generation was normal in nine (25%) and absent in 11 (31%). Given these results, recombinant (r) IL-2 was tested for its capacity to stimulate or enhance IFN-gamma production. rIL-2 (10 U/ml) alone stimulated cells from controls, ARC, and AIDS patients to secrete 93 +/- 25, 99 +/- 33, and 7 +/- 3 U/ml of IFN-gamma, respectively. rIL 2 (10 U/ml) plus antigen induced no change in mean IFN-gamma levels for controls, a 4.4-fold increase for 17 AIDS patients (16 +/- 16 vs. 71 +/- 21 U/ml), and a 7.2-fold increase (18 +/- 5 vs. 130 +/- 27 U/ml) for 19 ARC patients with abnormal IFN-gamma generation to antigen alone. Individual responses indicated that six of the 17 (35%) AIDS patients with opportunistic infections and 12 of the 19 (63%) with ARC were apparent responders to 10-100 U/ml of rIL-2. These results (a) document profound impairment in antigen-induced IL-2 secretion by AIDS and ARC T cells, (b) indicate that, in vitro, mononuclear cells from certain patients can respond to rIL-2 with enhanced IFN-gamma production, and thus (c) suggest that in selected patients rIL-2 might have a potentially beneficial therapeutic (AIDS) or prophylactic (ARC) effect against opportunistic infections.     

Standard- and high-dose etoposide, ifosfamide, carboplatin, and epirubicin in 107 patients with non-small-cell lung cancer: A mature follow-up report

Background: We conducted a phase I–II trial to assess the activity of standard-dose (SDC) and high-dose chemotherapy (HDC) with etoposide, ifosfamide, cis/carboplatin, and epirubicin (VIP-E, VIC-E) in 107 patients with limited-stage (LS, stage I–IIIB) and extensive stage (ES, stage IV) non-small-cell lung cancer (NSCLC).Patients and methods: Updated results of a previously published trial are presented.Results: Response rates and survival after VIP-E were comparable to those of other standard-dose combination chemotherapies in NSCLC. Treatment-related mortality (TRM) in SDC was 3% in LS-NSCLC, and 8% in ES-NSCLC. TRM was 4% in patients selected for HDC by response rate and performance score. Five-year survival in LS-NSCLC was 12% after SDC, and 18% after HDC; it was 0% for both treatment protocols in ES-NSCLC.Conclusions: The activity of VIP-E SDC and VIC-E HDC is not superior to that of established protocols in the treatment of NSCLC. In view of the toxicity and TRM associated with this protocol, less aggressive regimens should be preferred for most patients. Whether selected patients with chemosensitive disease could benefit from VIP-E SDC and/or VIC-E HDC in an adjuvant or neo-adjuvant setting could not be determined within the scope of this study.     

Vascular endothelial growth factor (VEGF) mRNA expression in human tumor models of different histologies

Background: Vascular endothelial growth factor (VEGF) is a polypeptidewith specific effects on endothelial cell growth and blood vesselpermeability. Recent studies demonstrated a key role for VEGFin tumor neovascularization, which is a prerequisite for tumorproliferation and metastasis Patients and methods: We studied the expression of VEGF mRNAin a panel of 65 different human tumor xeno-grafts of varioushistologies using Northern and slot blot analyses. Analysisof vessel density was performed morphologically and after immunohistochemicalstaining of endothelial cells Results: High expression levels were observed in 22/65 tumors.In melanoma, colorectal, gastric, breast and lung cancers onlysingle tumors showed strong expression signals, whereas 7/10renal cell carcinoma (RCC) xenografts demonstrated high levelsof VEGF mRNA. Vessel density analysis revealed a clear correlationof VEGF mRNA expression with vascularization in RCC (p - 0.0048).Patient survival time was compared for tumors showing high versuslow expression values. The overall 5-year survival rate wassignificantly lower for patients with high expression of VEGFmRNA (p - 0.0306) Conclusions: These data support the hypothesis that tumor cellsof various histologies secrete VEGF, which acts as a paracrinefactor to induce endothelial cell proliferation and vessel formationand mediates tumor progression VEGF, VPF, angiogenesis, vascularization, renal cell carcinoma, human tumor xenografts     

Production and regulation of interleukin-2 in human lymphoblastic leukemias studied with T-cell monoclonal antibodies

Human leukemias are illnesses of hemopoietic stem cells that go through processes of self-replication and partial differentiation under the control of as yet largely unknown growth and differentiation factors. IL-2 is a powerful factor controlling proliferation of normal T cells. We report that acute lymphoblastic leukemias of T and non-B, non-T phenotypes produce a growth factor after mitogen stimulation. This factor is able to support the proliferation of human and murine IL-2- dependent cytotoxic cells, has a mol wt of 26,000 daltons by gel filtration, an isoelectric point of 6.6, and its biologic activity is inhibited by an anti IL-2 monoclonal antibody. This factor is, therefore, by all parameters studied very similar to IL-2 produced by normal lymphocytes. A recently developed monoclonal antibody, Pan T2, binds to normal T cells, renders T cells responsive to IL-2, and induces the release of IL-2, which in turn provides the second signal for T-cell proliferation. Mononuclear cells from acute lymphoblastic leukemia do not respond to the addition of this monoclonal antibody unless cocultured with irradiated Daudi cells. Since normal T cells do not require Daudi to produce IL-2 and since Daudi cells do not produce IL-2 under any conditions, we conclude that the cell responsible for IL- 2 production in acute lymphatic leukemia is a leukemic T cell with an altered mechanism of IL-2 production at the level of the Pan T2 binding site.