Biomedical subjects

Thomas E Witzig

Publications and source records attributed to Thomas E Witzig.

95 records · Page 6Linked to original sources

PubMed2002

Treatment of late-stage Sézary syndrome with 2-Chlorodeoxyadenosine.

BACKGROUND: 2-Chlorodeoxyadenosine (2-CdA), a purine adenosine analog, is safe and effective chemotherapy for patients with hairy cell leukemia and low-grade lymphomas. Adverse effects include neutropenia, lymphocytopenia, and infectious complications. Our objective was to evaluate the efficacy of 2-CdA (2-6 seven-day cycles) in the treatment of late-stage, recalcitrant Sézary syndrome. METHODS: Retrospective review of medical records of six patients with Sézary syndrome who had received 2-CdA cycles at Mayo Clinic, Rochester between March 1995 and March 2000. Variables assessed from the records included improvement in global appearance, extent of erythroderma, size of lymph nodes, pruritus, and leukocyte, lymphocyte, and absolute Sézary cell counts. RESULTS: Two patients, both with stage III Sézary syndrome, whose previous treatment consisted of only two modalities, responded well to the treatment, with moderate to total clearing of erythroderma and pruritus associated with a significant decrease in Sézary cell counts. The other four patients had only a partial response (one patient) or no response (three patients) to 2-CdA. The mortality rate was 50%. All three patients died of Staphylococcus aureus sepsis. However, only one patient was receiving 2-CdA treatment when he died. The other two patients died 8 and 9 weeks after the last 2-CdA cycle. This high mortality rate is attributed to infectious complications after 2-CdA treatment in patients with recalcitrant disease. CONCLUSION: 2-Chlorodeoxyadenosine shows efficacy in stage III Sézary syndrome, but it also carries a substantial risk of septic complications and mortality. It can be used if no other suitable alternatives are available. Caution should be exercised in all these patients regarding skin care and avoidance of infections or sepsis.

Aged↗

PubMed2002

Bone marrow angiogenesis in 400 patients with monoclonal gammopathy of undetermined significance, multiple myeloma, and primary amyloidosis.

PURPOSE: To determine whether bone marrow (BM) angiogenesis progressively increases along the spectrum of plasma cell disorders ranging from monoclonal gammopathy of undetermined significance (MGUS) to advanced myeloma. EXPERIMENTAL DESIGN: Four hundred patients with the following disorders were studied: MGUS (76 patients); smoldering (indolent; early-stage) multiple myeloma (SMM; 112 patients); newly diagnosed, active multiple myeloma (MM; 99 patients); relapsed (advanced) multiple myeloma (RMM; 26 patients); and primary amyloidosis (AL; 87 patients). Forty-two normal control BM samples were studied for comparison. BM angiogenesis was studied in a blinded manner by immunohistochemical staining for CD34 to identify microvessels. RESULTS: The median (range) microvessel density (MVD) per x400 high power field was 1.3 (0-11) in the controls, 1.7 (0-10) in AL, 3 (0-23) in MGUS, 4 (1-30) in SMM, 11 (1-48) in newly diagnosed MM, and 20 (6-47) in RMM; P < 0.001. MVD was significantly higher in MGUS, SMM, newly diagnosed MM, and RMM compared with controls and AL; P < 0.001. MVD was not significantly different between controls and AL. By grading, high-grade angiogenesis was present in 0% of controls and AL, 1% of MGUS, 3% of SMM, 29% of newly diagnosed MM, and 42% of RMM; P < 0.001. MVD correlated with the BM plasma cell labeling index (rho = 0.46, P < 0.001) and BM plasma cell percentage (rho 0.5, P < 0.001). Survival was 28 months in SMM and newly diagnosed MM with high-grade angiogenesis, compared with 53 months for those with low- and intermediate-grade angiogenesis; P = 0.02. CONCLUSIONS: BM angiogenesis progressively increases along the spectrum of plasma cell disorders, from the more benign MGUS stage to advanced myeloma, indicating that angiogenesis may be related to disease progression.

Amyloidosis↗

PubMed2002

Hormone replacement therapy and risk of non-hodgkin lymphoma and chronic lymphocytic leukemia.

Our objective in this study was to evaluate whether the use of hormone replacement therapy (HRT) is associated with non-Hodgkin lymphoma (NHL) or chronic lymphocytic leukemia (CLL). A cohort of 37,220 Iowa women ages 55 to 69 years in 1986 with no history of prior cancer was linked annually to a population-based cancer registry. Through 1998 (13 years of follow-up), 258 incident cases of NHL were identified, including 135 cases of diffuse NHL, 58 cases of follicular NHL, and 31 cases of small lymphocytic NHL. In addition, 63 cases of CLL were identified. Current and former use of HRT (primarily estrogen) and other cancer risk factors were self-reported on the baseline (1986) questionnaire. Compared with never users of HRT at study baseline, current [multivariate relative risk (RR), 1.4; 95% confidence intervals (CIs), 0.9-2.0) but not former (RR, 1.1; 95% CI, 0.8-1.4) users were at increased risk of NHL after adjustment for age and other confounding factors. This association was seen only in nodal NHL [RR(current), 1.5 (95% CI, 1.0-2.4); RR(former), 1.1 (95% CI, 0.8-1.6)] and was not apparent for extra-nodal sites. Of the common subtypes, there was a strong positive association with follicular NHL [RR(current), 3.3 (95% CI, 1.6-6.9); RR(former), 2.6 (95% CI, 1.4-4.7)], and women who were current users for more than 5 years had the highest risk (RR, 3.9; 95% CI, 1.8-8.6). There was no association with diffuse or small lymphocytic NHL, or with CLL. Most of the follicular NHLs were nodal (88%), and exclusion of extra-nodal sites slightly strengthened the association with HRT. For diffuse NHL, 64% of the cases were nodal, and there was no association of HRT with either nodal or extra-nodal sites. These data suggest that HRT is a risk factor for follicular NHL but not for diffuse or small lymphocyte NHL or CLL.

Aged↗

PubMed2002

Promising preclinical activity of 2-methoxyestradiol in multiple myeloma.

PURPOSE: 2-Methoxyestradiol (2ME2), a natural endogenous product of estradiol metabolism, has demonstrated activity against tumor cell lines and can inhibit angiogenesis. There are limited treatment options for patients with multiple myeloma (MM) who relapse after high-dose therapy and stem cell transplantation. We studied the preclinical activity of 2ME2 as a therapeutic agent for myeloma. EXPERIMENTAL DESIGN: Five established myeloma cell lines as well as primary plasma cells from patients with MM were exposed to 2ME2 at various concentrations. We evaluated the activity of the drug to inhibit cell replication and induction of apoptosis in vitro as well as the ability of the drug to inhibit myeloma tumor xenograft growth in severe combined immunodeficient mice. RESULTS: 2ME2 inhibited tritiated thymidine uptake in all myeloma cell lines tested in a dose-dependent fashion and induced G(2)-M phase cell cycle arrest. The drug induced apoptosis in all cell lines tested and in half of the primary plasma cells evaluated in a dose-response manner. Forty-eight h after drug exposure, a large proportion of the cells were dead by propidium iodide staining. Injection of the drug i.p. suppressed myeloma tumor xenograft growth, and the effect was sustained after cessation of therapy. CONCLUSIONS: 2ME2 has significant activity against myeloma cell lines and primary myeloma cells both in vitro and in an animal model. Clinical trials are required to evaluate its activity in patients with MM.

2-Methoxyestradiol↗

PubMedDate not supplied

Targeting apoptosis pathways in cancer therapy.

Apoptosis, or programmed cell death, is a mechanism by which cells undergo death to control cell proliferation or in response to DNA damage. The understanding of apoptosis has provided the basis for novel targeted therapies that can induce death in cancer cells or sensitize them to established cytotoxic agents and radiation therapy. These novel agents include those targeting the extrinsic pathway such as tumor necrosis factor-related apoptosis-inducing ligand receptor 1, and those targeting the intrinsic Bcl-2 family pathway such as antisense bcl-2 oligonucleotides. Many pathways and proteins control the apoptosis machinery. Examples include p53, the nuclear factor kappa B, the phosphatidylinositol 3 kinase pathway, and the ubiquitin/proteosome pathway. These can be targeted by specific modulators such as bortezomib, and mammalian target of rapamycin inhibitors such as CCI-779 and RAD 001. Because these pathways may be preferentially altered in tumor cells, there is potential for a selective effect in tumors sparing normal tissue. This article reviews the current understanding of the apoptotic pathways, including the extrinsic (cytoplasmic) and intrinsic (mitochondrial) pathways, and the agents being developed to target these pathways.

Antibodies, Monoclonal↗