Phase I study of Topotecan, a new topoisomerase I inhibitor, in patients with refractory or relapsed acute leukemia

The purpose of this study was to define, in a phase I study in leukemia, the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of Topotecan, a new topoisomerase I (topo I) inhibitor. Topotecan was delivered by a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 3.5 mg/m2 to 18 mg/m2 per course. Twenty-seven patients were treated, including 17 patients with acute myelogenous or undifferentiated leukemia, 7 with acute lymphocytic leukemia, and 3 with chronic myelogenous leukemia in blastic phase. Severe mucositis was the dose-limiting toxicity occurring in two of five patients treated with Topotecan 11.8 mg/m2 per course; a third patient had prolonged myelosuppression. At the MTD of 10 mg/m2 per course, 1 of 12 patients had severe mucositis and 5 had mild-to- moderate mucositis. Nausea, vomiting, diarrhea, and prolonged myelosuppression were uncommon. Three patients (11%) achieved a complete response, two (7%) had a partial response, and one (4%) had a hematologic improvement. The overall complete plus partial response rate was 19%, and 24% in acute myelogenous or undifferentiated leukemia. A novel in vitro assay that quantifies Topotecan-stabilized topo I-DNA complexes in patient samples was used, which demonstrated heterogeneity in the ability of Topotecan to interact with topo I, the intracellular target of Topotecan. This phase I study defined the MTD of Topotecan to be 10 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Severe mucositis was the dose-limiting toxicity. Future studies will define the precise activity of Topotecan in different leukemia subsets, its efficacy in combination with other antileukemic drugs, and correlations between Topotecan-induced topo I-DNA complex formation and individual patient response to Topotecan.     

Immune reconstitution in severe combined immunodeficiency disease after lectin-treated, T-cell-depleted haplocompatible bone marrow transplantation

We describe our 9-year experience with lectin-treated T-cell-depleted haplocompatible parental bone marrow transplantation (BMT) for 24 patients with severe combined immunodeficiency disease (SCID). Nineteen of 21 evaluable patients had T-cell engraftment; 2 of 11 patients tested had B-cell and monocyte engraftment. Fourteen of 24 (58%) patients are alive 7 months to 9.8 years post-BMT. Seventeen of 24 patients received pretransplant conditioning with chemotherapy and/or total body irradiation, and 8 of 24 received more than one transplant. Patients who received conditioning had a survival rate of 61% versus 57% for those who received no conditioning. None received graft-versus- host disease (GVHD) prophylaxis and no patient had acute or chronic GVHD greater than grade I. Kinetics and follow-up of immune recovery were analyzed in 14 patients who are greater than 1 year from transplant. Half of the patients showed evidence of T-cell function by 3 months and normal T-cell function by 4 to 7 months post-BMT. On average, T-cell numbers and subsets became normal 10 to 12 months posttransplant. Recovery of B-cell function was more delayed, although in most patients B-cell numbers and IgM levels were normal by 12 months post-BMT. B-cell function, as determined by isohemagglutinin titers or specific antibodies to pneumococcal polysaccharide, keyhole limpet hemocyanin, or tetanus toxoid, became normal in 10 of 14 patients 2 to 8 years post-BMT. Seven of the 14 are off gammaglobulin therapy. Production of isohemagglutinins tended to predict recovery of antibody response to pneumococcal polysaccharide (P < .064). Based on these results, we believe that haplocompatible BMT is an effective, curative treatment for patients with SCID who lack an HLA-matched related donor.     

Heterogeneity of breakpoints of 11q23 rearrangements in hematologic malignancies identified with fluorescence in situ hybridization

Twenty-four patients whose cells contained a variety of 11q23 rearrangements, including translocations, insertions, and an inversion, were studied using fluorescence in situ hybridization with cosmid, phage, and plasmid probes mapped to 11q22-24. In 17 patients, the breakpoints of the common 11q23 translocations involving chromosomes 4, 6, 9, and 19 as well as some uncommon translocations involving 3q23, 17q25, 10p11, and an insertion 10;11 were all located in the breakpoint cluster region of the MLL gene, regardless of age, phenotype of disease, or involvement of a third chromosome. The breakpoints in 11q23 in the other 7 patients with a t(7;11)(p15;q23), inv(11)(p11q23), t(4;11)(q23;q23), der(5)t(5;11)(q13;q23), ins(10;11)(p11;q23q24), t(11;14)(q23;q11), or t(11;18;11) (p15;q21;q23) were located either centromeric to CD3D or telomeric to THY1. Thus, although most 11q23 rearrangements, involve the same breakpoint cluster region of MLL, there is heterogeneity in the breakpoint in some of the rare rearrangements.     

Detection and viability of tumor cells in peripheral blood stem cell collections from breast cancer patients using immunocytochemical and clonogenic assay techniques [see comments]

Although peripheral blood stem cell collections (PBSC) are thought to have less tumor involvement than bone marrow (BM), the incidence of circulating tumor cells in patients with breast cancer has not been widely investigated. We prospectively investigated the incidence and viability of tumor cell involvement in PBSC and BM collections from breast cancer patients undergoing high-dose chemotherapy/hematopoietic stem cell transplantation. Paired samples of PBSC and BM from 48 patients were analyzed using an immunocytochemical technique that detects one epithelial-derived tumor cell per 5 x 10(5) mononuclear cells. Immunostained tumor cells were detected in 9.8% (13/133) PBSC specimens from 9/48 (18.7%) patients and in 62.3% (38/61) BM specimens from 32/48 (66.7%) patients, a significantly higher rate than in PBSC (P < .005). The geometric mean concentration of tumor cells in contaminated PBSC specimens was 0.8/10(5) mononuclear cells (range 0.33 to 2.0/10(5)) compared with 22.9/10(5) mononuclear cells in BM (range 1 to 3,000/10(5), P < .0001). In culture experiments, clonogenic tumor colonies grew in 21/26 immunocytochemically positive specimens. No tumor colony growth was detected in 30/32 immunocytochemically negative specimens. Immunocytochemical detection of tumor involvement in BM and PBSC correlated significantly with in vitro clonogenic growth (P < .0001). We conclude that PBSC contain fewer tumor cells than paired BM specimens from patients with advanced breast cancer and that these tumor cells appear to be capable of clonogenic growth in vitro.     

Primary Care and Hepatology Provider–Perceived Barriers to and Facilitators of Hepatitis C Treatment Candidacy and Adherence

Background

Provider perceptions regarding barriers to and facilitators of hepatitis C (HCV) treatment initiation and adherence have not been fully evaluated in the interferon-free treatment era. New treatments have provided opportunities for non-specialists to treat HCV, underscoring the importance of understanding primary care provider (PCP) and specialist perspectives.

Methods

Based on qualitative sampling principles, 12 PCPs and 12 hepatology providers (HPs) from the VA Pittsburgh Healthcare System completed audio-recorded semi-structured interviews. Qualitative analysts coded perceived barriers and facilitators from the interviews with 100% double coding. Codes were thematized and analyzed using Atlas.ti.

Results

Key barriers to treatment described by HPs and PCPs included patients’ substance use disorders, mental health, transportation availability, history of non-adherence, and concern about side effects. PCPs also focused on medication cost as a system-based barrier. The main facilitators of treatment initiation and adherence described by both HPs and PCPs were provider education and encouragement. HPs focused almost exclusively on provider-based facilitators, while PCPs noted patient-based facilitators including past adherence, media exposure to information about HCV medications, a desire to clear the virus, and positive feedback regarding treatment response.

Conclusions

Providers generally focused on perceived patient-level barriers to HCV treatment initiation and adherence, as well as provider-level facilitators; PCPs additionally noted patient preferences and system-level issues that guide decision making regarding treatment initiation. While HPs focused almost exclusively on provider-level facilitators, PCPs additionally focused on patient-level facilitators of treatment. These data provide novel insights and suggest focusing on patient, provider, and system-level strategies to further improve HCV treatment initiation and adherence.

     

Renal and Urologic Complications of Inflammatory Bowel Disease

Renal and urologic complications are not uncommon in patients with inflammatory bowel disease, and can be directly or indirectly related to the underlying disease process or its treatment. Many of these patients have asymptomatic disease, or the urinary symptoms are nonspecific or overshadowed by bowel symptoms. By the time a urinary complication is considered, significant disease progression or renal damage may have occurred. These risks necessitate a high degree of diligence and periodic urologic evaluation as part of the long-term management of patients with inflammatory bowel disease.     

A mutation in the transmembrane/luminal domain of the ryanodine receptor is associated with abnormal Ca2+ release channel function and severe central core disease

Central core disease is a rare, nonprogressive myopathy that is characterized by hypotonia and proximal muscle weakness. In a large Mexican kindred with an unusually severe and highly penetrant form of the disorder, DNA sequencing identified an I4898T mutation in the C-terminal transmembrane/luminal region of the RyR1 protein that constitutes the skeletal muscle ryanodine receptor. All previously reported RYR1 mutations are located either in the cytoplasmic N terminus or in a central cytoplasmic region of the 5,038-aa protein. The I4898T mutation was introduced into a rabbit RYR1 cDNA and expressed in HEK-293 cells. The response of the mutant RyR1 Ca2+ channel to the agonists halothane and caffeine in a Ca2+ photometry assay was completely abolished. Coexpression of normal and mutant RYR1 cDNAs in a 1:1 ratio, however, produced RyR1 channels with normal halothane and caffeine sensitivities, but maximal levels of Ca2+ release were reduced by 67%. [3H]Ryanodine binding indicated that the heterozygous channel is activated by Ca2+ concentrations 4-fold lower than normal. Single-cell analysis of cotransfected cells showed a significantly increased resting cytoplasmic Ca2+ level and a significantly reduced luminal Ca2+ level. These data are indicative of a leaky channel, possibly caused by a reduction in the Ca2+ concentration required for channel activation. Comparison with two other coexpressed mutant/normal channels suggests that the I4898T mutation produces one of the most abnormal RyR1 channels yet investigated, and this level of abnormality is reflected in the severe and penetrant phenotype of affected central core disease individuals.     

Branched chain and aromatic amino acids change acutely following two medical therapies for type 2 diabetes mellitus

ObjectiveElevated circulating levels of branched chain and aromatic amino acids (BCAA/AAAs) are associated with insulin resistance and incident type 2 diabetes (T2D). BCAA/AAAs decrease acutely during an oral glucose tolerance test (OGTT), a diagnostic test for T2D. It is unknown whether changes in BCAA/AAAs also signal an early response to commonly used medical therapies for T2D.Materials and MethodsA liquid chromatography–mass spectrometry approach was used to measure BCAA/AAAs in 30 insulin sensitive (IS) and 30 insulin resistant (IR) subjects before and after: 1) one dose of a sulfonylurea medication, glipizide, 5 mg orally; 2) two days of twice daily metformin 500 mg orally; and 3) a 75-g OGTT. Percent change in BCAA/AAAs was determined after each intervention.ResultsFollowing glipizide, which increased insulin and decreased glucose in both subject groups, BCAA/AAAs decreased in the IS subjects only (all P < 0.05). Following metformin, which decreased glucose and insulin in only the IR subjects, 4 BCAA/AAAs increased in the IR subjects at or below P = 0.05, and none changed in the IS subjects. Following OGTT, which increased glucose and insulin in all subjects, BCAA/AAAs decreased in all subjects (P < 0.05).ConclusionsBCAA/AAAs changed acutely during glipizide and metformin administration, and the magnitude and direction of change differed by the insulin resistance status of the individual and the intervention. These results indicate that BCAA/AAAs may be useful biomarkers for monitoring the early response to therapeutic interventions for T2D.     

Combination of a Calcium Antagonist, Verapamil, with an Angiotensin Converting Enzyme Inhibitor, Trandolapril, in Experimental Myocardial Ischemia and Reperfusion: Antiarrhythmic and Hemodynamic Effects of Chronic Oral Pretreatment

The combination of a calcium antagonist with an angiotensin-converting enzyme (ACE) inhibitor is increasingly used in the therapy of hypertension, but there are no experimental data supporting the use of this combination in acute myocardial ischemia and reperfusion. We tested the effects of oral pretreatment in a pig model, paying special attention to arrhythmias and adverse hemodynamic effects. Pigs received verapamil 240 mg + trandolapril 4 mg, verapamil 240 mg, or placebo orally once daily for 10 days, after which a coronary artery was ligated for 20 minutes and then allowed to reperfuse. The ventricular fibrillation threshold (VFT) was measured during ischemia to assess the vulnerability of the heart to ventricular fibrillation, whereas spontaneous tachyarrhythmias were monitored during reperfusion. Regional left ventricular (LV) blood flow was measured with radioactive microspheres. During the ischemic period, both the combination of verapamil plus trandolapril, and verapamil alone, prevented a fall in the VFT, indicating antiarrhythmic activity. The combination maintained LV contractile activity and cardiac output (CO) at preligation levels, whereas verapamil alone decreased cardiac output. During reperfusion, verapamil plus trandolapril prevented spontaneous ventricular tachyarrhythmias and increased blood flow in the reperfused zone. In contrast, verapamil was not antiarrhythmic and decreased CO. Thus the addition of the ACE inhibitor trandolapril to the calcium antagonist verapamil resulted in antiarrhythmic activity during ischemia and reperfusion, and produced a better hemodynamic profile.     

Variations by age in symptoms and dependency levels experienced by people in the last year of life, as reported by surviving family, friends and officials

OBJECTIVE: To explore the relationships between age, reported symptoms and dependency in the last year of life in those dying from cancer and in those dying from other causes. DESIGN: Secondary analysis of data from the Regional Study of Care for the Dying, a retrospective interview survey of deaths in 1990 in 20 nationally representative English health districts. There were 2061 cancer deaths and 1469 non-cancer deaths (sudden deaths were excluded). MAIN RESULTS: In cancer patients, the mean number of symptoms reported to have been experienced in the last year of life decreased with age (from 8.29 in those aged <65 to 7.79 in those aged 65 -74, 7.37 in those aged 75-84 and 7.42 in those aged 85 and older), while the number of symptoms reported to have lasted more than 6 months increased (2.93, 3.15, 3.24 and 3.52). In both cancer and non-cancer patients the proportion of symptoms reported to have been 'very distressing' decreased with age (cancer, 45, 43, 40 and 35%; non-cancer, 39, 38, 34 and 27%). In non-cancer patients the mean number of self-care tasks the deceased had needed help with increased substantially with age (2.23, 2.50, 3.04 and 3.95); in cancer patients the mean level was higher and there was no age gradient (3.89, 3.94, 3.83 and 4.1). The prevalence of dependency on most of the seven self-care tasks in cancer patients was comparable with or higher than that in the older and most restricted non-cancer patients. CONCLUSION: Younger cancer patients are more likely than older cancer patients to need help with relieving distressing symptoms. However, some elderly patients were reported to have had very distressing symptoms, and these patients should not be excluded from specialist palliative care services on the basis of their age. Cancer patients did not show increased dependency with age, indicating the importance of community health and social services being appropriate for and accessible by cancer patients of all ages.