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Purpose: Fostriecin is an inhibitor of topoisomerase II catalytic activity. In a phase I trial we observed renal toxicity, documented as a rise in serum creatinine, which was reversible and non-dose-limiting. The purpose of this study was a detailed analysis of this toxicity., Methods: A total of 20 patients received fostriecin as a 1-h i.v. infusion daily x 5 at doses ranging from 2 to 20 mg/m2 per day. Serum creatinine determination and urinalysis were performed daily during drug administration. Renal hemodynamics were measured by means of clearance studies using 125I-iothalamate and (131)I-hippuran in eight patients at doses of > or =4 mg/m2 per day at baseline, on day 3 or 4 during the first course, and 3 weeks after the second course., Results: The rise in serum creatinine was maximal after one to two doses despite continued administration. This increase showed no correlation with the dose level at fostriecin doses of > or =4 mg/m2 per day. Urinary beta2-microglobulin concentrations increased 150-fold (median), which is compatible with impaired tubular reabsorption. The median change in the glomerular filtration rate (GFR) was -36% (range -28% to -44%), that in effective renal plasma flow (ERPF) was -23% (range -11% to -36%), and the filtration fraction (FF) decreased in all patients during the first course of treatment. The values measured 3 weeks after the second course, however, did not differ from baseline., Conclusions: Fostriecin induces reversible renal hemodynamic changes compatible with renal tubular damage.

Apart from modulation of tumor-cell drug sensitivity, induction of differentiation might be an alternative in the treatment of tumors resistant to cytotoxic drugs. In this report the capacity to induce differentiation and to modulate the cis-diamminedichloroplatinum(II) (CDDP) sensitivity of all-trans-retinoic acid (RA), docosahexaenoic acid (DCHA), and hexadecylphosphocholine (HePC) is examined in human germ-cell tumor cell lines. In the embryonal carcinoma cell line Tera-2 and its 3.7-fold CDDP-resistant subline Tera2-CP, we evaluated the effects of 96 h of pretreatment with RA (0.1 microM), DCHA (23 microM), and HePC (25 microM) on differentiation induction and on CDDP-induced cytotoxicity, DNA platination (4-h incubation), and apoptosis (continuous incubation). Without drug treatment, Tera2-CP showed less apoptosis than Tera-2. Pretreatment with RA decreased the cytotoxicity and apoptosis induced by CDDP without resulting in decreased DNA platination and increased differentiation in both cell lines. DCHA enhanced CDDP-induced cytotoxicity and apoptosis and did not affect the embryonal character of either cell line. HePC did not affect CDDP cytotoxicity or differentiation in either cell lines. Effects of the modulators on differentiation and on CDDP-induced cytotoxicity, DNA platination, and apoptosis did not differ between Tera-2 and Tera2-CP. RA can be applied for differentiation induction in CDDP-resistant germ-cell tumor models. However, in this model, RA reduced the apoptotic susceptibility. DCHA potentiated CDDP cytotoxicity in vitro; its in vivo modulatory capacity in germ-cell tumor cells deserves further study.

The cytotoxic action of two morpholino anthracyclines, methoxymorpholino anthracycline (MRA-MT, FCE 23,762) and cyanomorpholino anthracycline (MRA-CN), was compared with the cytotoxicity of doxorubicin (DOX), the topoisomerase II inhibitor etoposide (VP-16), the topoisomerase I inhibitor camptothecin, methotrexate, and cisplatin in GLC4, a human small-cell lung-cancer cell line, in GLC4-Adr, its P-glycoprotein (Pgp)-negative, multidrug-resistant (MDR; 100-fold DOX-resistant) subline with overexpression of the MDR-associated protein (MRP) and a lowered topoisomerase II activity, and in GLC4-CDDP, its cisplatin-resistant subline. GLC4-Adr was about 2-fold cross-resistant for the morpholino anthracyclines and GLC4-CDDP was, relative to GLC4, more resistant for the morpholino anthracyclines than for DOX. Overall, MRA-CN was about 2.5-fold more cytotoxic than MRA-MT. The cytotoxicity profile of the morpholino anthracyclines in these cell lines mimicked that of camptothecin.

Cells exhibiting decreased topoisomerase II (Topo II) activity are resistant to several drugs that require Topo II as an intermediate. These drugs are cytotoxic due to the formation of a cleavable complex between the drug, Topo II and DNA. Fostriecin belongs to a new class of drugs that inhibit Topo II without inducing the formation of this cleavable complex. We tested fostriecin in three human small-cell lung carcinoma cell lines. GLC4 is the parent line. GLC4/ADR is the P-glycoprotein-negative multidrug-resistant subline, which is resistant to several Topo II inhibitors due to its decreased Topo II activity. GLC4/cDDP is the cisplatin-resistant subline, which displays increased Topo II activity. Topo II activity proved to be 100% in GLC4, 35% in GLC4/ADR and 130% in GLC4/cDDP. The fostriecin concentration causing inhibition of the growth of 50% of the cells (IC50) in the microculture tetrazolium assay following continuous incubation was 11.2, 4.1 and 14.9 microM, respectively. After 1-h incubations, the IC50 was 117.8, 101.3 and 219.8 microM, respectively. Our results indicate a relationship between Topo II activity and fostriecin sensitivity in these closely related cell lines. At least in vitro, fostriecin displayed the capacity to kill cells showing resistance to drugs due to decreased Topo II activity. There was no relationship between this capacity and an increase in the activity of the reduced-folate carrier system, the proposed mechanism for cellular entry of fostriecin, since we found no correlation between the cytotoxicity of fostriecin and that of methotrexate.

(NPAz2)2NSOAz ('SOAz') is the first of a new class of cytotoxic agents containing an inorganic heterocyclic ring system to enter clinical trial. It was used to treat 31 patients with advanced cancer by IV infusion over 30 min on days 1, 2, 3, and 4 of a 21-day cycle, which was postponed if necessary to allow for hematological recovery. A total of 46 courses evaluable for toxicity was given and the tumor response was evaluable in 21 patients. Seven dose levels, ranging from 25 mg/m2 to 300 mg/m2, were studied, with three to six patients at each level. The only major toxicity was myelosuppression, especially thrombocytopenia, which was dose-limiting. Platelets decreased from the 14th day onward, with a nadir 4-5 weeks after administration. Leukopenia was less predictable and reached a nadir 3-5 weeks after administration. In most patients recovery was complete after 6-9 weeks. Myelosuppression was clearly cumulative in succeeding courses and proved irreversible in three patients. Anemia also occurred, but otherwise SOAz was remarkably well tolerated. There were no responses and no therapy-related deaths. The highest tolerated dose for patients who had received no or only minor chemotherapy prior to treatment with SOAz was 300 mg/m2, and that for heavily pretreated patients, 175 mg/m2. Because of cumulative myelotoxicity phase II studies with SOAz are not recommended.

Pharmacokinetic studies of 1,3,3,5,5 pentakis (aziridino)-1 lambda 6,2,4,6,3 lambda 5,5 lambda 5 thiatriazadiphosphorine-1-oxide ('SOAz'), a new antineoplastic agent containing an inorganic ring system and five aziridino groups, were performed in six patients who took part in a phase I clinical trial of the agent. The drug was administered as a rapid IV infusion. Serum decay curves could be fitted to an open two-compartment model of drug disappearance. After a short initial phase with a t 1/2 (+/- SD) of 7.8 +/- 4.2 min a terminal phase with a dose-independent half-life of 203 +/- 17 min occurred. The coefficient of apparent distribution was 0.71 +/- 0.13. The renal clearance was 75 +/- 11 ml/min and the total body clearance 162 +/- 23 ml/min. A percentage of 46.5 +/- 6.6 of the administered drug could be recovered unchanged in the urine within 24 h. It is concluded that in view of concentrations known to be effective in vitro, administration in large single doses may be advantageous. Dose adjustments should be made for patients with impaired renal function.

We studied renal function in nine patients with disseminated testicular carcinoma before and after remission-induction and maintenance therapy with a drug combination containing cis-platinum. The median glomerular filtration rate (GFR) decreased during remission-induction therapy from 146 to 118 ml/min. No effect of cumulative toxicity on the median GFR was found during maintenance therapy, nor did the median GFR improve. The median effective renal plasma flow (ERPF) decreased during the total period from 705 to 514 ml/min. No significant changes in median filtration fraction (FF) and serum creatinine were observed. It is suggested that intrarenal hemodynamic effects are important in the nephrotoxicity of cis-diamminedichloride platinum (CDDP).

A 62-year-old woman developed subacute renal failure after the repeated administration of ifosfamide (IFX), despite its combination with continuous sodium 2-mercaptoethane sulfonate (mesna) infusion. Biopsy findings, the possible underlying mechanism, and the existing literature are discussed.

A total of 28 previously treated patients with small-cell lung cancer were treated at relapse with 400 mg/m2 carboplatin and 2 mg vincristine on days 1 and 8, every 4 weeks. Ten partial responses (PRs) (37%) but no complete responses (CRs) were seen. Median survival after the start of second-line treatment was 120 days (range, 39-503 days). Toxicity of this regimen was moderate, including WHO grade 3/4 myelosuppression in 26% of courses (n = 66). Eight PRs were seen in a subgroup of 22 patients who relapsed less than 3 months after first-line treatment. The responses seen in this group of patients may be due to the absence of cross-resistance between the regimens used.

Ten previously untreated patients with metastatic non-seminomatous testicular carcinoma received cis-diamminedichloroplatinum (CDDP). Renal function studies were performed before and following the first CDDP infusion. A decrease in effective renal plasma flow (ERPF) and an increase in filtration fraction (FF) was found in all patients. These findings suggest primary changes in renal hemodynamics during CDDP infusion.

Pulmonary function tests, including spirometry, transfer factor of the lungs for carbon monoxide (TlCO), and the two components of TlCO, the diffusing capacity of the alveolocapillary membrane (Dm) and pulmonary capillary blood volume (Vc), were carried out in a group of patients with testicular carcinoma during and after treatment with the Einhorn regimen. The lung function parameters of patients who developed bleomycin-induced pneumonitis were compared with those recorded in a group of patients who did not develop this syndrome. We suggest that bleomycin-induced damage to the pulmonary capillary vasculature can be monitored by measuring Vc and that ensuing fibrosis can be measured by recording Dm. The decrease in Dm is probably compensated for by an increase in Vc, leading to a smaller change in TlCO.

On the assumption that hemodynamic changes in renal blood flow are the initial expression of cis-diamminedichloroplatinum (CDDP)-related nephrotoxicity, we treated patients with metastatic non-seminomatous testicular carcinoma during CDDP infusion with captopril. This angiotensin-converting enzyme inhibitor significantly attenuated the initial decrease in effective renal plasma flow and can probably be used to protect the kidneys against CDDP-induced nephrotoxicity.