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K C Anderson

Publications and source records attributed to K C Anderson.

At least 91 records · Page 5Linked to original sources

Management of multiple myeloma today.

Multiple myeloma is almost invariably fatal despite a wide variety of chemotherapeutic and supportive treatment options. There are several unresolved problems with existing approaches, including the specific indications for treatment; the optimal combination of agents and doses; and the type, frequency, and timing of high-dose therapy and stem-cell transplantation. High-dose chemotherapy followed by stem-cell transplantation produces higher remission rates, but patients rarely, if ever, are cured by a single regimen. Allogeneic hematopoietic stem-cell transplantations offer a potential graft-versus-myeloma (GVM) effect. Researchers are focusing efforts on improving the safety of transplant procedures, increasing response rates to ablative therapy, and testing novel posttransplant options to improve outcomes. The newly devised National Comprehensive Cancer Network (NCCN) guidelines for treating multiple myeloma are also discussed.

Humans↗

Role of cytokines in multiple myeloma.

Recent research in the biology of multiple myeloma (MM) has produced new insight into the factors that control the growth and survival of myeloma cells. In particular, there is a greater appreciation of the pathogenic role of the cytokines, such as interleukin-6 (IL-6) and IL-1beta in the conversion of monoclonal gammopathy of undetermined significance (MGUS) to MM and in the proliferation and survival of myeloma cells. Infection of dendritic cells with Kaposi's sarcoma-associated herpesvirus (KSHV), which secretes a viral homolog of IL-6, may also be a factor. As a direct application of recent laboratory observations, several immune-based treatment strategies are being developed.

Cytokines↗

Adenovirus vector-based purging of multiple myeloma cells.

Adenoviruses are efficient gene delivery agents for a variety of neoplasms. In the present study, we have investigated the use of adenoviruses for the delivery of the thymidine kinase (tk) gene into multiple myeloma (MM) cells. We first demonstrated that MM cell lines and MM patient cells express both adenovirus receptors as well as the DF3/MUC1 protein, thus providing a rationale for using adenoviruses to selectively deliver genes under the control of the DF3 promoter. By using an adenoviral construct containing beta-galactosidase (beta-gal) gene driven by the DF3 promoter (Ad. DF3-betagal), we demonstrate greater than 80% transduction efficiency in OCI-My5 and RPMI 8226 MM cell lines at a multiplicity of infection of 1 to 100. Importantly, transduction with the tk gene driven by the DF3 promoter (Ad.DF3-tk) followed by treatment with 50 micromol/L ganciclovir (GCV) purged >/=6 log of contaminating OCI-My5 and RPMI 8226 MM cells within bone marrow mononuclear cells. In contrast, normal human hematopoietic progenitor cell number was unaffected under these conditions. Selectivity of DF3/MUC1 promoter was further confirmed, because Ad.DF3-betagal or Ad.DF3-tk did not transduce MUC1-negative HeLa cervical carcinoma cells. In addition, GCV treatment of Ad.DF3-tk-transduced RPMI 8226 MM cells did not induce a significant bystander effect. These findings demonstrate that transduction with Ad vectors using a tumor-selective promoter provides a highly efficient and selective approach for the ex vivo purging of MM cells.

Adenoviridae↗

Anti-estrogens induce apoptosis of multiple myeloma cells.

Previous studies have suggested that multiple myeloma (MM) cells express estrogen receptors (ER). In the present study, we characterized the effects of estrogen agonists and antagonists (anti-estrogens [AE]) on growth of MM cell lines and MM patient cells. In addition to antagonizing estrogen binding to ER, AE can trigger apoptosis. Hence, we also determined whether estrogens or AE altered MM cell survival. Immunoblotting showed that ER-alpha is expressed in 4 of 5 MM cell lines (ARH-77, RPMI 8226, S6B45, and U266, but not OCI-My-5 cells), as well as in freshly isolated MM cells from 3 of 3 patients. 17beta-estradiol (E2) did not significantly alter proliferation of MM cell lines or MM patient cells. In contrast, two structurally distinct AE, tamoxifen (TAM) and ICI 182,780 (ICI), significantly inhibited the proliferation of all 5 MM cell lines and MM cells from 2 of 2 patients (IC50, 2 to 4 micromol/L). Proliferation of these cell lines was also inhibited by the hydroxylated TAM derivative, 4-hydroxytamoxifen (4HTAM), although this derivative was less potent than TAM (IC50, 3 to 25 micromol/L). In contrast, the dehalogenated TAM derivative toremifene (TOR) did not inhibit MM cell proliferation. We next examined the effects of these agents on MM cell survival. TAM, ICI, and, to a lesser extent, 4HTAM and TOR triggered apoptosis in both ER-alpha-positive as well as ER-alpha-negative MM cell lines and patient MM cells, evidenced both by fluorescence-activated cell sorting (FACS) analysis using propidium iodide staining and the TUNEL assay. TAM-induced growth inhibition and apoptosis of ER-alpha-positive S6B45 MM cells was not blocked by coculture with excess E2. TAM-induced apoptosis of S6B45 MM cells was also unaffected by addition of exogenous interleukin-6. Importantly, both the inhibition of MM cell proliferation and the induction of MM cell apoptosis were achieved at concentrations of TAM (0.5 and 5.0 micromol/L) that did not significantly alter in vitro growth of normal hematopoietic progenitor cells. Similar plasma levels of TAM have been achieved using high-dose oral TAM therapy, with an acceptable toxicity profile. These studies therefore provide the rationale for trials to define the utility of AE therapy in MM.

Apoptosis↗

MDM2 protein overexpression inhibits apoptosis of TF-1 granulocyte-macrophage colony-stimulating factor-dependent acute myeloblastic leukemia cells.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a growth factor for acute myeloblastic leukemia (AML) cells. Murine double minute 2 (MDM2) oncoprotein, a potent inhibitor of wild-type p53 (wtp53), can function both to induce cell proliferation and enhance cell survival, and is frequently overexpressed in leukemias. Therefore, we focused on the importance of MDM2 protein in GM-CSF-dependent versus GM-CSF- independent growth of AML cells. The TF-1 AML cell line, which has both wtp53 and mutant p53 genes, showed GM-CSF-dependent growth; deprivation of GM-CSF resulted in G1 growth arrest and apoptosis. MDM2 mRNA and protein were highly expressed in proliferating TF-1 cells in the presence of GM-CSF and decreased significantly with deprivation of GM-CSF. In contrast, p53 protein increased with GM-CSF deprivation. Ectopic overexpression of MDM2 in TF-1 AML cells conferred resistance to GM-CSF deprivation, and is associated with decreased p53 protein expression. Moreover, a variant of TF-1 cells that grows in a GM-CSF-independent fashion also expressed high levels of MDM2 and low levels of p53. These results suggest that GM-CSF-independent growth of AML cells is associated with overexpression of MDM2 protein and related modulation of p53 expression.

Animals↗

Lack of selectivity for simple shapes defined by motion and luminance in STPa of the behaving macaque.

The anterior superior temporal polysensory area (STPa) has been hypothesized to be an integration site for signals coming from the dorsal and ventral visual pathways. To determine whether neurons in STPa were selective for simple two-dimensional geometrical shapes and whether this area might integrate different visual cues, cells were tested with motion- and luminance-defined shapes. Many neurons were activated by the shape stimuli under at least one condition; however, very few showed selectivity for a particular shape under either condition. Only one neuron responded selectively to shapes defined by both cues. Thus selectivity for simple shapes is not a prevalent property of STPa neurons and the integration of luminance and motion signals does not appear to occur at the single neuron level in STPa.

Animals↗

Toxicity and efficacy of defined doses of CD4(+) donor lymphocytes for treatment of relapse after allogeneic bone marrow transplant.

Donor lymphocyte infusions (DLI) can induce remissions in patients who have relapsed after allogeneic bone marrow transplantation (BMT). However, DLI frequently also result in significant acute and/or chronic graft-versus-host disease (GVHD). Several clinical and experimental lines of evidence have suggested that CD8(+) T cells play a critical role in the pathogenesis of GVHD. To develop methods to reduce the incidence of GVHD associated with DLI, we administered defined numbers of CD4(+) donor T cells after ex vivo depletion of CD8(+) lymphocytes to 40 patients with relapsed hematologic malignancies after allogeneic BMT. Cohorts of patients received 0.3, 1.0, or 1.5 x 10(8) CD4(+) cells/kg. Overall, 12 of 38 patients (32%) evaluable for toxicity developed acute or chronic GVHD. However, 6 of 27 patients (22%) receiving 0.3 x 10(8) CD4 cells/kg developed GVHD compared with 6 of 11 patients (55%) who received >/=1.0 x 10(8) CD4 cells/kg (P = .07). Treatment-related mortality was low (3%), with 1 death related to infection in the setting of immunosuppression for GVHD. Disease responses after CD4(+) DLI were documented in 15 of 19 patients (79%) with early-phase chronic myelogenous leukemia (CML) relapse, 5 of 6 patients (83%) with relapsed multiple myeloma, and 1 patient with myelodysplasia. For patients with early-phase CML relapse, the Kaplan-Meier probability of achieving complete cytogenetic remission was 87% and the probability of complete molecular response was 78% at 1 year after DLI. The median time to complete cytogenetic response and molecular response in patients with CML was 13 weeks (range, 9 to 30 weeks) and 34 weeks (range, 10 to 56 weeks), respectively. The median time to response in patients with multiple myeloma was 26 weeks (range, 15 to 62 weeks). All patients in this trial who developed GVHD demonstrated tumor regression, but the presence of GVHD was not required for patients to achieve a response, because 48% of responding patients never developed evidence of GVHD. Two patients with CML who did not respond at dose level 1 subsequently achieved complete cytogenetic remission after a second infusion of CD8-depleted cells at dose level 2. In patients with evidence of mixed hematopoietic chimerism who achieved a complete remission after DLI, cytogenetic analysis of marrow cells also demonstrated conversion to complete donor hematopoiesis in all evaluable patients. These studies suggest that relatively low numbers of CD8-depleted donor lymphocytes are effective in inducing complete remissions in patients with stable-phase CML and multiple myeloma who have relapsed after allogeneic BMT. Because of the relatively low risk of toxicity associated with the infusion of defined numbers of CD4(+) donor cells, further studies can be undertaken in the setting of persistent minimal residual disease to prevent relapse after allogeneic BMT.

Adult↗

The 86-kD subunit of Ku autoantigen mediates homotypic and heterotypic adhesion of multiple myeloma cells.

Previous studies have shown that triggering multiple myeloma (MM) cells via CD40 induces IL-6-mediated autocrine growth as well as increased expression of cell surface adhesion molecules including CD11a, CD11b, CD11c, and CD18. In this study, we generated the 5E2 mAb which targets an antigen that is induced upon CD40 ligand (CD40L) activation of MM cells. Immunofluorescence, immunoprecipitation, and protein sequencing studies identified the target antigen of 5E2 mAb as the 86-kD subunit of the Ku autoantigen. We demonstrate that increased cell surface expression of Ku on CD40L-treated cells is due to migration of Ku from the cytoplasm to the cell surface membrane. Moreover, cell surface Ku on CD40L-treated MM cells mediates homotypic adhesion of tumor cells, as well as heterotypic adhesion of tumor cells to bone marrow stromal cells and to human fibronectin; and 5E2 mAb abrogates IL-6 secretion triggered by tumor cell adherence to bone marrow stromal cells. These data suggest that CD40L treatment induces a shift of Ku from the cytoplasm to the cell surface, and are the first to show that Ku functions as an adhesion molecule. They further suggest that cell surface Ku may play a role in both autocrine and paracrine IL-6-mediated MM cell growth and survival.

3T3 Cells↗

CD6+ T cell-depleted allogeneic bone marrow transplantation for non-Hodgkin's lymphoma.

For patients with non-Hodgkin's lymphoma (NHL) undergoing blood or bone marrow transplantation (BMT), the use of autologous grafts has often been preferred to that of allogeneic stem cells because of a significantly lower incidence of non-relapse mortality. If complications associated with allo-BMT could be minimized without compromising efficacy, then it might become a preferred strategy for certain subsets of patients. In this report, we describe the toxicity and long-term efficacy of T cell-depleted allogeneic BMT using anti-CD6 monoclonal antibody and complement alone to reduce the risk of GVHD and its sequelae. Twenty-two patients, aged 18-60 years, with high (n = 10), intermediate (n = 9), or low (n = 3) grade NHL underwent HLA-identical allogeneic BMT from siblings. Patients had either relapsed after at least one remission or never achieved a full remission with chemotherapy. Twenty patients had a history of marrow involvement. Bone marrow was depleted of CD6+ T cells with T12 monoclonal antibody and complement as the sole form of GVHD prophylaxis. Stable hematopoietic engraftment occurred in all 22 patients. Four patients developed grade 2 and 1 patient grade 3 GVHD (23% grades 2-4 GVHD). Chronic GVHD has occurred in three patients. Treatment-related mortality was very low. Only one patient died while in remission. Thirteen patients are alive and free of disease with a median follow-up of 30 months. Estimated event-free and overall survivals are 54 and 59%, respectively. CD6 allogeneic marrow transplantation is associated with a low risk of transplant-related complications and may offer advantages for certain patients with recurrent NHL felt to be at high risk for relapse after autologous transplantation.

Adolescent↗

Anti-B4-blocked ricin: a phase II trial of 7 day continuous infusion in patients with multiple myeloma.

This phase II trial was undertaken to determine the toxicities, response rate, pharmacokinetics and frequency of human anti-mouse antibody (HAMA) and anti-ricin antibody (HARA) when the B-cell restricted immunotoxin anti-B4-bR was administered to patients with previously treated multiple myeloma (MM). Five patients with MM were scheduled to receive a 7 d continuous infusion of anti-B4-bR. The initial four patients received therapy at 40 microg/kg lean body weight (LBW)/d. Two patients received a 7 d infusion, one patient received 6 d, and another patient 5 d of therapy. The fifth patient was treated for 7 d at a lower dose of 30 microg/kg LBW/d because of the side-effects observed in the initial patients. Pharmacokinetic studies demonstrated a peak serum level >2.6 nM in three of the patients. Side-effects of therapy included hepatic transaminase elevations, myalgias, thrombocytopenia, nausea, vomiting, decrease in performance status, and capillary leak syndrome. One patient developed HAMA and two patients HARA. One patient developed neurologic toxicity with akinetic mutism, and died following therapy. No patient demonstrated a significant decline in M-component during therapy. We concluded that anti-B4-bR can be administered by continuous infusion to patients with multiple myeloma, although immunotoxin levels >3 nM were associated with increased incidence of toxicity and required dose adjustment. Future trials using anti-B4-bR in MM will be needed to determine the optimal dose and administration schedule in this patient population, and to determine whether there is evidence of biologic activity.

Adult↗

Nationwide survey of home transfusion practices.

BACKGROUND: Limited information exists on home transfusion practices. STUDY DESIGN AND METHODS: In 1995, a survey requesting data for 1994 was sent to 1273 American Association of Blood Banks (AABB) institutional members and 113 non-AABB home health care agencies that provide out-of-hospital transfusions. RESULTS: Of 943 respondents, 102 provide blood to a home transfusion program, 37 provide blood and run a home transfusion program, and 13 run a home transfusion program only, for a total of 152 (16%) with some involvement in home blood transfusions. Most of the 50 respondents with a home transfusion program are licensed by their state and accredited by the Joint Commission on Accreditation of Healthcare Organizations. All respondents have written policies for home transfusion, and 90 percent require a signed informed-consent document before initiating transfusions in the home. Most have policies requiring that there be a second adult and a telephone in the home, that the home be deemed safe for transfusion, that the patient's physician be readily available, and that the patient have had prior transfusions. The most common component issued by the blood providers was red cells, followed by platelets. White cell-reduced components were always provided by 36 percent of respondents. The most common patient diagnosis was cancer. Home transfusions were provided primarily by registered nurses. Only 14 percent of respondents indicated that the medical director of the blood bank is responsible for approving a patient for home transfusion. A posttransfusion visit is performed by 46 percent of respondents. CONCLUSION: Although most facilities have policies for the administration of home transfusions, there remains marked heterogeneity among blood providers and transfusionists regarding home transfusion practices.

Adult↗

Sequential CD34+ and CD4+ cell selection from leukapheresis components.

We tested the feasibility of sequential selection of CD34+ and CD4+ cell-enriched fractions from aliquots of five autologous leukapheresis components. CD34+ cells were selected from a median 8.0 x 10(8) mononuclear cells using the CellPro CEPRATE LC cell separation system. All cells in the CD34-depleted fraction (median 4.8 x 10(8), range 0.6-10.0 x 10(8) were then incubated with the appropriate antibodies for CD4+ cell selection and passed through a second LC column. Median target cell purities of the CD34+ cell-enriched fraction and CD4+ cell-enriched fraction were 90.5% and 86.0%, respectively. This study demonstrates that high purity CD34+ and CD4+ cell-enriched fractions can be isolated sequentially from leukapheresis components. In addition, CD8+ lymphocytes, implicated in graft-versus-host disease, were depleted in the course of both positive selection procedures. This approach could decrease the number of donor procedures by providing separate CD34(+)-enriched and CD4(+)-enriched populations for allogeneic peripheral blood progenitor cell transplantation and subsequent donor lymphocyte infusion from the same leukapheresis component.

Antigens, CD34↗

High-dose chemoradiotherapy and anti-B-cell monoclonal antibody-purged autologous bone marrow transplantation in mantle-cell lymphoma: no evidence for long-term remission.

PURPOSE: The role for high-dose therapy and autologous stem-cell transplantation in mantle-cell lymphoma (MCL) is unknown. We retrospectively analyzed patients with chemosensitive disease who underwent high-dose chemoradiotherapy and anti-B-cell monoclonal antibody-purged autologous bone marrow transplantation (ABMT) for MCL in first remission, as well as following relapse from conventional therapy. PATIENTS AND METHODS: Between August 1985 and April 1996, 28 patients underwent ABMT using a uniform ablative regimen with cyclophosphamide and total-body irradiation (TBI) and a bone marrow-purging regimen. Re-review of original tissue demonstrated that all patients had morphologic, phenotypic, and genotypic characteristics of MCL. MCL was the original diagnosis in 21 patients, whereas seven patients had a prior diagnosis of diffuse small cleaved-cell lymphoma. RESULTS: Twenty patients received multiple regimens before ABMT, while eight underwent ABMT in first complete remission (CR)/partial remission (PR) following CHOP induction. At bone marrow harvest, only 18% of patients were in CR and overt BM infiltration was present in 57%. Following cyclophosphamide/TBI, no treatment-related deaths were seen. Nineteen of 28 patients have relapsed at a median time of 21 months (range, 3 to 70). Of eight patients transplanted in first CR/PR, five have relapsed. Nine patients are in continuous CR with a median follow-up time of 24 months (range, 10 to 135). Disease-free survival (DFS) and overall survival (OS) are estimated to be 31% and 62% at 4 years, respectively. CONCLUSION: ABMT using cyclophosphamide/TBI conditioning may at best be effective in only a small fraction of patients with relapsed MCL. The lack of plateau with a median follow-up time of 24 months suggests cure may not be achievable. The role of this therapy in patients in first remission requires more study using better induction therapy to enhance the CR rate before ABMT.

Adult↗

Interleukin-6 in multiple myeloma and related plasma cell dyscrasias.

Since the discovery a decade ago that interleukin-6 is a growth factor for human multiple myeloma (MM) cells, great strides have been made in understanding the relationship of this cytokine to multiple myeloma. A plethora of studies on this topic has confirmed that interleukin-6 is a key growth and survival factor for myeloma cells, as well as a major morbidity factor for patients with MM. Their is strong evidence for both an autocrine (in MM cells) as well as a paracrine sources of interleukin-6 induction (from bone marrow stromal cells and osteoblast cells), with bone marrow stromal cells likely serving as the main center of production of interleukin-6 in patients with MM. Moreover, bone marrow stromal cells from patients with MM express viral interleukin-6, a functional homolog of human interleukin-6 that is produced by Kaposi's sarcoma-associated herpesvirus and may further enhance MM cell growth and survival. Soluble interleukin-6 receptor serum levels are elevated in patients with MM; soluble interleukin-6 receptor may amplify circulating interleukin-6 in patients with MM, and complex with interleukin-6, resulting in proliferation of MM cells that either express low or no detectable surface interleukin-6 receptor. Recent advances in our understanding of interleukin-6 signaling cascades mediating MM growth and survival, as well as its impact on cell cycle regulation in MM cells, may lead to therapeutics designed to interfere with these pathways. Finally, considerable progress has been made in identifying and developing agents including antibodies, biologic agents, hormones and drugs that interfere with the interleukin-6 signaling pathways and may therefore have a role in the treatment of MM.

Animals↗

p16INK4A promotes differentiation and inhibits apoptosis of JKB acute lymphoblastic leukemia cells.

Homozygous p16(INK4A) (p16) gene deletion is frequent in primary tumor cells from acute lymphoblastic leukemia (ALL), suggesting that loss of p16 may be an important precursor to transformation in ALL. We have previously described JKB, a human ALL cell line, that contains homozygous deletion of the p16 gene. Because ectopic expression of p16 suppresses cell growth, we created a temperature sensitive p16 mutant to develop a system for inducible p16 function in human ALL. JKB cells were transfected either with a p16 gene mutated at position 119 (E119G) to confer temperature sensitivity (JKB p16MT) or with control vector. The percentage of cells in G1 phase was similar in JKB control cells or in JKB p16MT cells cultured at restrictive conditions (40 degrees C). However, with lowering of temperature from 40 degrees C to permissive conditions (31 degrees C), the percentage of JKB p16MT cells in G1 phase and binding of p16 to CDK4 and CDK6 increased, with associated decreases in CDK4 and CDK6 kinase activities, and dephosphorylation of retinoblastoma protein (pRB). Culture of JKB p16MT cells at 31 degrees C for >/=3 days irreversibly inhibited growth. Moreover, JKB p16MT cells cultured under these permissive conditions showed a less transformed morphology and more differentiated phenotype than did these cells cultured under restrictive temperatures. Finally, dexamethasone (Dex) induced apoptosis of JKB p16MT cells cultured at 40 degrees C, but did not trigger death of these cells cultured at 31 degrees C. These results suggest that deletion of p16 gene in JKB human ALL cells is associated with dysregulated growth of less differentiated tumor cells, which nonetheless remain susceptible to apoptosis triggered by Dex.

Amino Acid Sequence↗

IL-6 triggers cell growth via the Ras-dependent mitogen-activated protein kinase cascade.

IL-6 mediates growth of some human multiple myeloma (MM) cells and IL-6-dependent cell lines. Although three IL-6 signaling pathways (STAT1, STAT3, and Ras-dependent MAPK cascade) have been reported, cascades mediating IL-6-triggered growth of MM cells and cell lines are not defined. In this study, we therefore characterized IL-6 signaling cascades in MM cell lines, MM patient cells, and IL-6-dependent B9 cells to determine which pathway mediates IL-6-dependent growth. IL-6 induced phosphorylation of JAK kinases and gp130, regardless of the proliferative response of MM cells to this growth factor. Accordingly, we next examined downstream IL-6 signaling via the STAT3, STAT1, and Ras-dependent mitogen-activated protein kinase (MAPK) cascades. IL-6 triggered phosphorylation of STAT1 and/or STAT3 in MM cells independent of their proliferative response to IL-6. In contrast, IL-6 induced phosphorylation of Shc and its association with Sos1, as well as phosphorylation of MAPK, only in MM cells and B9 cells that proliferated in response to IL-6. Moreover, MAPK antisense, but not sense, oligonucleotide inhibited IL-6-induced proliferation of these cells. These data suggest that STAT1 and/or STAT3 activation may occur independently of the proliferative response to IL-6, and that activation of the MAPK cascade is an important distal pathway for IL-6-mediated growth.

Adaptor Proteins, Signal Transducing↗