H. Poliwoda

Home therapy with recombinant interleukin-2 and interferon-α2b in advanced human malignancies

The safety, tolerance, and clinical effects of a home therapy regimen of recombinant human interleukin-2 (rIL-2) and interferon-alpha 2b (IFN-alpha 2b) self injected subcutaneously have been assessed in 35 patients with advanced cancer refractory to standard therapy. 52 treatment cycles were given, each consisting of a 2-day rIL-2 pulse of 9.0 million IU/m2 every 12 h, followed by 6 weeks of rIL-2 1.8 million IU/m2 twice daily for 5 days per week and of IFN-alpha 2b 5.0 million U/m2 thrice a week. The main adverse effects were fever, chills, nausea, anorexia, and hypotension and were limited to WHO grades of severity I and II in 29 of 35 patients. No treatment-related deaths occurred. The response rates among patients with renal-cell carcinoma were similar to those reported for high-dose intravenous regimens of interleukin-2 that are toxic and have to be given in hospital.

Interleukin-2 in combination with interferon-α and 5-fluorouracil for metastatic renal cell cancer

Recent clinical trials for the biological therapy of solid tumours have used recombinant human cytokines in combination with conventional chemotherapy. In patients with progressive metastatic renal cell carcinoma, we established a three-drug combination comprising interferon-alpha (IFN-alpha), interleukin-2 (IL-2) and 5-fluorouracil (5-FU), using a regimen which allows outpatient therapy. Treatment consisted of 8 weeks each of IFN-alpha [6-9 MU/m2 once to three times weekly subcutaneously (sc)] combined sequentially with IL-2 (5-20 MU/m2 thrice weekly sc for 4 weeks) and 5-FU [750 mg/m2 intravenously (i.v.) weekly for 4 weeks]. Among the first 35 patients treated, there were 4 complete (11.4%) and 13 partial responders (37.1%), with an overall objective response rate of 48.6% (95% confidence interval 32-66%). Regressions occurred in local relapse, in lung, lymph node, bone, pleural, renal and thyroid metastases. Median response duration was calculated at 7+ months. An additional 13 patients (37.1%) were stable throughout therapy and thereafter (median of 6+ months). Response rate of this three-drug combination regimen compared favourably with single agent IFN-alpha (objective response rate approximately 16%) and against the sc IFN-alpha/IL-2 combination (objective response rate approximately 28%). Systemic toxicity was mild to moderate with no severe 5-FU-related mucositis and no dose-limiting adverse effects of sc IL-2. While the exact mechanisms of the potentially additive or synergistic effects of 5-FU and IFN-alpha/IL-2 remain to be established in more detail, it appears that the sequential use of IFN-alpha/IL-2 and IFN-alpha/5-FU in metastatic renal carcinoma further enhances the therapeutic index of IFN-alpha/IL-2-based biological therapy. Based on the present data, combined biochemotherapy may be a promising new approach to the therapy of advanced renal cancer.

Chemoimmunotherapy of advanced malignant melanoma: sequential administration of subcutaneous interleukin-2 and interferon-α after intravenous dacarbazine and carboplatin or intravenous dacarbazine, cisplatin, carmustine and tamoxifen

Both chemotherapy and interleukin-2 and/or interferon-alpha produce objective responses in a proportion of advanced malignant melanoma patients. While duration of response to chemotherapy is short, i.e. usually below 4 months, immunotherapy has resulted in a small number of long-lasting remissions in patients with metastatic melanoma. In two consecutive phase II trials in a total of 67 patients, we assessed the potential synergism between both modalities, i.e. chemo- and immunotherapy. Treatment consisted of intravenous (i.v.) carboplatin (CBDCA, 400 mg/m2) and dacarbazine (DTIC, 750 mg/m2) given twice (i.v. bolus over 30 min) at 3-week intervals, or 4 cycles of DTIC (220 mg/m2 i.v. 3 days), cisplatin (DDP, 35 mg/m2 i.v. 3 days), carmustine (BCNU, 150 mg/m2 i.v. cycles 1 and 3) and tamoxifen (TAM, 20 mg oral/daily) at 3-week intervals. Chemotherapy was followed by immunotherapy with combined subcutaneous (s.c.) interleukin-2 (rIL-2) and SC interferon-alpha 2 (rIFN-alpha). Among 40 patients who received a full cycle of chemotherapy with CBDCA/DTIC and sequential immunotherapy, there were 3 (7.5%) complete remissions (CRs) with a median duration of 19 months (range 13-26+). Partial remissions (PRs) were noted in 11 (27.5%) patients with a median response duration of 8 (range 5-14) months. Among 27 patients who received DTIC/DDP/BCNU/TAM and rIL-2/rIFN-alpha, there were 3 (11%) complete remissions and 12 (44.5%) partial remissions. Duration of complete and partial remissions ranged from 9+ to 13+ (median, 11+), and 5 to 15+ (median, 7+) months, respectively. Chemotherapy produced mostly moderate toxicity. Thrombocytopenia was common with the nadir after a median time of 18 days following start of CBDCA/DTIC and DTIC/DDP/BCNU, respectively. 10 patients required transfusion of thrombocytes. Nausea and vomiting due to chemotherapy were well tolerated using concomitant ondansetrone (8 mg i.v.). Immunotherapy was self-administered at home with mild to moderate side effects; malaise, fever, chills, nausea/vomiting, diarrhoea, anorexia and arthralgias were most frequent, but were spontaneously reversible after ending rIL-2/IFN-alpha. A mean 87 and 88% of the projected doses of rIL-2 and rIFN-alpha were administered on either protocol. There were no life-threatening complications and no treatment-related deaths. The sequential combination of chemotherapy and rIL-2 plus rIFN-alpha had at least additive therapeutic activity against metastatic malignant melanoma. The schedules produced long-lasting remissions and were tolerated well overall. These trials substantiate a potential role for low to intermediate dose immunotherapy in maintaining and consolidating therapeutic effects of chemotherapy in metastatic melanoma.

Biochemotherapy of advanced metastatic renal-cell carcinoma: results of the combination of interleukin-2, alpha-interferon, 5-fluorouracil, vinblastine, and 13-cis-retinoic acid.

SummaryWe conducted a phase I/II clinical trial evaluating the sequential outpatient combination of S.C. recombinant human interleukin-2 (rIL-2; given at 10 MIU/m2 b.i.d. on days 3–5 of weeks 1 and 4 and at 5 MIU/m2 on days 1, 3, and 5 of weeks 2 and 3), s.c. recombinant human alpha-interferon (rIFN-α; given at 6 MIU/m2 on day 1 of weeks 1 and 4 and on days 1, 3, and 5 of weeks 2 and 3 and at 9 MIU/m2 on days 1, 3, and 5 of weeks 5–8), i.v. bolus 5-fluorouracil (5-FU; given at 1,000 mg/m2 once weekly during weeks 5–8), and i.v. bolus vinblastine (given at 6 mg/m2 once weekly during weeks 5 and 8) in conjunction with p.o. 13-cis-retinoic acid (13-C-RA; given at 35 mg/m2 daily during weeks 1–8). Therapy was always given in the outpatient setting. Grade 3 constitutional symptoms (malaise, chills, fevers, anorexia) were observed in 4%–8% of treatment cycles and required a 50% reduction in the doses of rIL-2 and rIFN-α. None of the patients experienced major 5-FU-related toxicities such as severe diarrhea and/or stomatitis; up to 20% of patients developed vinblastine-associated peripheral polyneuropathy, which was reversible after the cessation of therapy. 13-cis-Retinoic acid produced no significant side effect; no toxic death occurred. Among 24 patients with progressive metastatic disease, there were 4 complete remissions (lung, lymph nodes) and 6 partial remissions (lung, pleura, liver, lymph nodes, and peritoneal carcinosis), for an overall objective response rate of 42% (95% confidence interval, 22%–63%). An additional 13 patients achieved disease stabilization (54%). The median time to response was 3–4 months (range, up to 6 months); all responses are continuous. In summary, although the potential synergy of biochemotherapy plus 13-cis-retinoic acid requires further preclinical investigation, the current outpatient combination regimen (rIL-2, rIFN-a, 5-FU, vinblastine, and 13-C-RA) proved to be both safe and highly effective in patients with advanced metastatic renal-cell carcinoma. A current multiinstitutional prospectively randomized trial is comparing biochemotherapy with and without concomitant 13-C-RA against rIFN-α plus vinblastine.

Effects of cytokines on in vitro colony formation of primary human tumour specimens

Although under study to alleviate chemotherapy-induced bone marrow toxicity, cytokines can stimulate in vitro growth of solid human tumour cell lines. The effects of granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF) and interleukin-3 (IL-3) on in vitro colony formation of primary human tumours was studied in a capillary soft-agar cloning system. Of 108 tumour specimens from 100 patients, 85 specimens were tested against all three factors at concentrations ranging from 0.1 to 1000 ng/ml. 44 of 100 tumours showed adequate growth in controls. 8 out of 43 (19%) specimens were significantly stimulated by GM-CSF, 6 of 40 (15%) by G-CSF and 10 of 44 (23%) by IL-3. Sensitivity to all three cytokines was observed in 4 of 44 (9%) specimens. By light microscopy the appearance of colonies from stimulated specimens was identical to that of controls. Sensitivity to cytokines was independent from sensitivity to epidermal growth factor, transferrin or insulin. Sensitivity to GM-CSF, G-CSF and IL-3 may be aberrantly expressed in a subgroup of solid human tumours.

Soluble interleukin 2 receptors abrogate IL-2 induced activation of peripheral mononuclear cells

Soluble interleukin 2 receptors (sIL-2R) exert a potential role in immunoregulation. We investigated the in vitro effects of sIL-2R on several interleukin 2 (IL-2)-dependent cellular events. Cytotoxicity of human rIL-2-stimulated PBMC against K562 and Daudi was correlated inversely to the concentration of sIL-2R in the culture medium during rIL-2 stimulation. sIL-2R concentrations higher than 4.0 pM produced a significant loss of cytotoxicity (P < 0.01). The effect of different sIL-2R concentrations added to cultured human PBMC on secondary sIL-2R production was tested by ELISA. Secondary sIL-2R production was abrogated by high initial sIL-2R dosages whereas low initial dosages were followed by a continuing production of secondary sIL-2R after five days of culture. Proliferation of the IL-2-dependent mouse cell line CTLL-2-was suppressed by sIL-2R added to the culture medium in a dose-dependent way. The neutralizing capacity of sIL-2R strongly depended on the initial number of CTLL set in per proliferation assay. In contrast, variation of rIL-2-concentration had no significant effect on reduction of proliferation by sIL-2R. Furthermore, preincubation of sIL-2R with rIL-2 did not enhance growth suppression. These last findings indicate that there is at least no functional interaction between sIL-2R and free IL-2, whereas an interaction of sIL-2R with the membrane-bound receptor for IL-2 seems possible.

Immunocytochemical Detection of P-Glycoprotein: Initial Expression Correlates with Survival in Renal Cell Carcinoma Patients

We evaluated 28 patients with advanced renal cell carcinoma for the initial expression of P-glycoprotein (MDR1 gene product) employing immunocytochemistry. Tumor specimens were obtained upon primary tumor nephrectomy. In all patients, progression-free survival time following nephrectomy was evaluated and correlated statistically with the staining results. Progression-free survival of patients with no or very few (< 1%) P-glycoprotein-positive tumor cells (n = 8, median survival 27.0 months) was significantly extended (p < 0.04) as compared to patients with 1% or more P-glycoprotein-positive tumor cells (n = 20, median survival 4.0 months). Correlations with histopathological tumor characteristics were insignificant. These results suggest a potential role for P-glycoprotein as a biologic parameter predictive of tumor progression in renal cell carcinoma patients.

Lack of therapeutic efficacy of tamoxifen in advanced renal cell carcinoma.

In the present study, we treated a total of 62 patients with advanced renal cell carcinoma with high-dose tamoxifen (100 mg/m2/day). Patients were treated in the outpatient setting, and were evaluated 8-12 weeks after initiation of therapy or sooner, when clinical disease progression was evident; a total of 15 patients were seen at short regular intervals for evaluation of clinical and laboratory parameters. Of these 62 patients, 59 were evaluable for treatment response, survival and systemic toxicity. One partial remission was achieved (1.7%; 95% confidence interval, 0.04-9.09%), response duration was 3 months. 10 patients presented with stable disease, for a median duration of 4.0 months, and 48 patients exhibited disease progression upon and after therapy. Systemic toxicity was significant; severe fatigue occurred in 5% of patients, and moderate anaemia, dyspnea, alopecia and malaise in almost 20% of patients. Antineoplastic efficacy of tamoxifen at this dosage in this cohort of patients was at best marginal and well in the range associated with the occurrence of spontaneous remissions. Toxicity was substantial, and it was not balanced by therapeutic benefit. This is consistent with the known lack of therapeutic efficacy of endocrine therapy in advanced renal cell carcinoma.

Effects of Recombinant Human Erythropoietin on Clonogenic Growth of Primary Human Tumor Specimens in vitro

Background: Production of Erythropoietin has been reported for various tumor cell lines in vitro. Also, a number of clinical reports indicate aberrant synthesis and release of erythropoietin, particul

Kinetik der Serumenzyme bei Behandlung des Herzinfarktes mit Streptokinase

SummaryThe effects of streptokinase or anticoagulants on the kinetics of the serum enzymes were investigated in a joint clinical study on the therapy of recent myocardial infarction. Streptokinase treatment gave significantly earlier and higher peaks of enzyme activities of GOT and LDH in the serum. Owing to the considerable number of determinations performed, the maximum enzyme levels were reached sooner (also in the control group) than in the majority of cases cited in the literature: GOT 21 h, CPK 13.5 h, and LDH 29 h after the onset of infarction. The enzyme maximum levels do not provide any information on the severity of the myocardial infarction but should be considered as a sequela of the altered haemodynamics.It was assumed that the more rapid flow of enzymes out of the infarction area with streptokinase medication resulted from the improved haemodynamics due to the lowered viscosity, increased microcirculation and recanalization of the obstructed coronary vessels. This applies likely to the improvement of the circulatory condition in the treatment of shock. In either case, a quicker transport of enzymes results which explains their altered behaviour.These processes have been formulated mathematically on the basis of a two-compartmental model.ZusammenfassungIn einer klinischen Gemeinschaftsstudie wurden die Einflüsse einer Behandlung des frischen Myokardinfarktes mit Streptokinase oder Anticoagulantien auf die Kinetik der Serumenzyme untersucht. Dabei fand sich unter Streptokinasebehandlung ein signifikant früherer und höherer Gipfel der Enzymaktivitäten der GOT und LDH im Serum. Die Enzymmaxima lagen aufgrund der häufigeren Bestimmungen auch bei der Kontrollgruppe vor den meist in der Literatur angegebenen Werten: GOT 21 Std, CPK 13,5 Std und LDH 29 Std nach Infarktbeginn. Die Höhe der Enzymmaxima gibt keinen Aufschluß über die Größe des Myokardinfarktes, sondern ist als Folge der hämodynamischen Alteration anzusehen.Als Ursache des rascheren Enzymausstroms aus dem Infarktgebiet unter Streptokinase wurde eine verbesserte Hämodynamik als Folge der Viscositätssenkung, der Verbesserung der Mikrozirkulation und der Rekanalisation des verschlossenen Coronargefäßes diskutiert. Analoges gilt für die Verbesserung der Kreislaufsituation bei der Schockbehandlung. In jedem Fall kommt es damit zu einem rascheren Enzymabtransport, aus dem das unterschiedliche Enzymverhalten resultiert.Diese Vorgänge wurden mathematisch anhand eines 2 Compartment-Modells formuliert.