Gemcitabine in the treatment of advanced head and neck cancer

AimsSeveral new chemotherapy agents show varying degrees of activity in head and neck cancer. One of them is gemcitabine, which is a new nucleoside analogue with an innovative cytostatic mode of action. Gemcitabine has demonstrated a broad spectrum anti-tumoural effect and a favourable toxicity profile. These attributes prompted us to introduce gemcitabine into the treatment of head-and-neck tumours.Materials and methodsTen heavily pre-treated patients with recurrent and incurable squamous-cell carcinoma of the head and neck (SCCHN) were treated with Gem. The initial cycle consisted of six administrations of the drug (1250 mg/m² once weekly intravenously over 30 min) followed by a week without cytotoxic treatment. All following cycles were composed of two infusions once weekly (d1, 8), followed by a week of rest.ResultsToxic effects, length of survival and tumour response was assessable in eight patients owing to one suicide and loss of one patient for follow-up. One complete remission, two partial remissions and three ‘no change’ situations (stable disease) were observed, yielding a response rate of 37.5%. Median survival was 8 months (range 3–12). The incidence of haematological toxicity was low, with grade 3–4 neutropenia in less than 10%. Flu-like symptoms were reported by one-third of patients.ConclusionsIn this small phase-II study, gemcitabine demonstrated a high anti-tumoural activity in SCCHN, with a favourable toxicity profile. Gemcitabine seems to be a promising new drug without severe burden even for patients who are refractory to other cytostatic drugs. Within recent years, the activity and tolerability of gemcitabine was documented in several phase I and phase II trials, especially in combination with cisplatin, and paclitaxel resp, carboplatin/paclitaxel, cisplatin/ifosfamide, and 5-fluorouracil/paclitaxel. The results of these trials will be outlined in the discussion.     

Specificity of CD8+ T cells from subunit-vaccinated and infected H-2b mice recognizing the 38 kDa antigen of Mycobacterium tuberculosis

CD8+ T cells have been implicated in protective anti-tuberculous immune responses, but little is known about the identity of mycobacterial antigens recognized by CD8+ T cells. In this study we identified the Mycobacterium tuberculosis 38 kDa protein as a target for murine CD8+ cytotoxic T lymphocytes (CTL) which were induced by vaccination of C57BL/6 mice with DNA delivered with a plasmid, with transfected tumour cells or by infection with tubercle bacilli. Using overlapping synthetic peptides covering the whole protein sequence, peptides predicted to contain H-2Kb or H-2Db motifs, as well as naturally processed peptides, we were able to identify CTL epitopes. Differences were demonstrated in peptide specificity between CTL from immunized or M. tuberculosis-infected mice. The identified CTL epitopes could be important for future analysis of the involvement of CD8+ T cells in M. tuberculosis infections and for vaccine development.      

Multiple polymorphic sites in factor X locus

The structure of factor X (FX) gene was analyzed in five FX deficient pedigrees with four different variants of the disease, as well as in 50 normal subjects. Genomic DNA from the deficient patients and the normal controls was digested with 12 restriction endonucleases and hybridized with a FX cDNA probe. The results seemingly exclude gross gene deletions or rearrangements in the deficient patients. A variety of polymorphic sites (ie, EcoRI, HindIII, PstI, PvuII, TaqI) was observed within the FX locus and their relative frequency was established. Intriguingly, a highly polymorphic region for the PvuII endonuclease was identified and located approximately 3 kilobases (kb) from the last 3' exon. These polymorphisms allowed us to analyze the allelic segregation in a FX deficient family and to identify a homozygous subject.     

Lymphocyte depletion of donor bone marrow by counterflow centrifugal elutriation: results of a phase I clinical trial

We report here the results of a phase I clinical trial using counterflow centrifugal elutriation (CCE) for the removal of donor T lymphocytes before allogeneic bone marrow transplantation (BMT). Thirty- eight patients received lymphocyte-depleted allografts from HLA- identical, MLR-nonreactive sibling donors. The patients entered onto the study were either at high risk on the basis of age (median, 39 years) or disease status (acute leukemia in early relapse [ER], chronic myelogenous leukemia [CML] in accelerated phase [AP], or therapy resistant [RES] lymphoma). All patients received a standard lymphocyte dose of 1 x 10(6) morphologic lymphocytes per kilogram ideal body weight (BW) and were maintained on cyclosporine A (CsA) for 170 days after BMT. Prompt engraftment occurred in 37 of 38 patients with a median time to absolute neutrophil count (ANC) greater than 500/microL of 18 days. Although acute graft-v-host disease (GVHD; clinical stage I or greater) was observed in 45%, it was limited to the skin in all but five patients. Survival was related to disease status at the time of BMT. Among patients with acute leukemia in first or second remission, CML in chronic phase (CP) or lymphoma in partial remission (PR), 64% are currently alive, in contrast to 31% of patients with acute leukemia in third remission or early relapse, CML in second CP or AP, or RES lymphoma. Median follow-up for all patients was 351 days (range, 105 to 711 days). We conclude that this procedure is safe and warrants further evaluation in a randomized efficacy trial.     

Two serologic markers to monitor the engraftment, growth, and treatment response of human leukemias in severe combined immunodeficient mice

We have investigated human lactate dehydrogenase (LDH) isoenzymes and human nuclear matrix protein 41/7 (NMP 41/7) as potential serologic markers to monitor the course of human leukemia in severe combined immunodeficient (SCID) mice. Following the transplantation of 10(6) human acute lymphoblastic leukemia (ALL) Nalm-6 cells, human specific LDH isoenzymes were measurable in the serum of SCID mice as early as 7 days after transplantation, although serum total LDH increased in some animals as early as 5 days after transplantation. Human NMP 41/7 was measurable in all animals at day 15 after leukemia cell injection. Serum levels of total LDH, human specific LDH and NMP 41/7 increased progressively over time, reaching total LDH levels as high as 50,000 U/L at day 25 after transplantation. To determine whether the levels of LDH and NMP 41/7 in serum were a reflection of human tumor burden, we studied these serologic markers in SCID mice bearing measurable subcutaneous human neuroblastoma tumors, or compared the serum levels of these markers with the number of human leukemia CD10+ cells in the bone marrow of the SCID mice. The serum levels of total LDH, human specific LDH isoenzymes, and NMP 41/7 correlated well with tumor burden, and they drastically decreased or disappeared from serum after the human leukemia or neuroblastoma cells were selectively killed with a single intravenous (IV) injection of 1 to 3 micrograms diphtheria toxin (DT) (the cellular receptor for DT is present on human cells, but not on mouse cells). Paraplegic mice with central nervous system leukemia completely recovered after DT treatment. We conclude that measurements of serum levels of total LDH, human LDH isoenzymes, and NMP 41/7 are sensitive, quantitative, rapid, and easy to perform serologic methods useful to monitor the engraftment, progression, and treatment response of human leukemia in SCID mice.     

尿中羟甲左吗喃、氨苄度冷丁、环丁甲羟氢吗啡及香草酰二乙胺的分析

本文用GC/NPD和GC/MSD的方法,对尿样中的麻醉镇痛剂羟甲左吗喃、氨苄度冷丁、环丁甲羟氢吗啡以及中枢神经刺激剂香草酰二乙胺等的母体药物及代谢产物进行了检测,建立了可靠、灵敏和快速测定麻醉镇痛剂的方法。     

β-受体阻滞剂的分析研究

本文叙述了用高效毛细管气相色谱/氮磷检测器及气相色谱/质量选择检测器对13种β-受体阻滞剂的分析研究。样品用不同衍生化方法作了比较,初步结果表明:衍生化效果TFAA与MBTEA无很大差异;而MSTFA比上述两者效果均佳。本文的研究为β-受体阻滞剂的体液气相色谱研究提供了可行的方法。     

Oxidative stress and antioxidant status in beta-thalassemia major: iron overload and depletion of lipid-soluble antioxidants

Because of continuous blood transfusions, thalassemia patients are subjected to peroxidative tissue injury by the secondary iron overload. In accordance, analysis of serum from 42 beta-thalassemia patients, aged 4 to 40 years, showed that the mean concentrations of conjugated diene lipid hydroperoxides (CD), lipoperoxides evaluated as malondialdehyde/ thiobarbituric acid (MDA/TBA) adducts, and protein carbonyls increased about twofold with respect to control. Ferritin levels were positively correlated with the amount of MDA (r = .41; P = .007) and showed a positive trend with CD (r = .31; P = .07) and protein carbonyls (r = .35; P = .054), as further evidence of the deleterious effects of high tissue iron levels. Marked changes in the antioxidant pattern were also observed in all patients. Evidence is presented of a net drop in the concentration of ascorbate (-44%), vitamin E (-42%), vitamin A(-44%), beta-carotene (-29%), and lycopene (- 67%). On the other hand, an increase of uric acid and bilirubin was observed, whereas serum albumin and glutathione were in the normal range in all patients. As a result, the total serum antioxidant potential, measured as trolox equivalent antioxidant capacity appeared significantly decreased by 14%. Serum levels of vitamin E were inversely correlated with ferritin (r = -.45; P = .003), suggesting a major consumption of this antioxidant under iron overload. Nontransferrin bound iron (NTBI) was in the range 4.5 to 54.8 micrograms/dL (mean, 21.8 +/- 13.9). Although NTBI had a positive trend with ferritin (r = .37, P = .03), no clear correlation was found with either MDA or vitamin E. A mild to severe hepatic damage, as assessed by serum transaminases, was shown in 24 of 42 patients. Serum levels of vitamin E (r = -.49, P = .015), vitamin A (r = -.48, P = .016) and lycopene (r = -.47, P = .020), were inversely correlated with the levels of transminases. On the other hand, lipid-soluble antioxidants in thalassemia patients were depleted to the same extent in hepatitis C virus (HCV)-infected (31 subjects) and in HCV-uninfected (10 subjects), while in the normal range in serum from 30 nonthalassemic patients with HCV-related chronic hepatitis. These results point out that the iron- induced liver damage in thalassemia may play a major role in the depletion of lipid-soluble antioxidants. The variations of the parameters evaluated in the present study were not correlated with the age of the patients. Our results suggest that the measurement of peroxidation products, matched with evaluation of antioxidants, may be a simple measure of iron toxicity in thalessemia, in addition to the conventional indices of iron status.