Systemic chemotherapy promotes HIF-1α-mediated glycolysis and IL-17F pathways in cutaneous T-cell lymphoma.

BACKGROUND: Systemic chemotherapy is often the last resort of advanced cutaneous T-cell lymphoma (CTCL). Tumor recurrence and adverse effects of systemic chemotherapy are the main limitations. OBJECTIVE: We aim to investigate the metabolic alterations in tumor cells after CHOP (cyclophosphamide, hydroxydaunorubicin, oncovin and prednisone) chemotherapy. METHODS AND RESULTS: In advanced CTCL, CHOP chemotherapy has no survival benefit and the duration of response is significantly inferior to other canonical treatments. HIF-1α is significantly elevated in lesions of advanced MF patients as well as tumor cell line Hut78 and tumor xenograft mice model. CHOP therapy also increased glycolytic activities in a HIF-1α-dependent manner. In CTCL xenograft tumor mice model, lesional cells showed a significant increase in IL-17F after chemotherapy, shifting toward a Th17 phenotype, which process is also regulated by HIF-1α. Echinomycin, HIF-1α inhibitor, was co-administered in xenograft tumor mouse models with CHOP and showed a significant reduction in tumor growth. CONCLUSION: CHOP chemotherapy promotes glycolysis and IL-17 pathways in a HIF-1α-dependent fashion. Furthermore, HIF-1α blockade is promising as an accompanying agent in systemic chemotherapy for patients with advanced CTCL.

Echinomycin inhibits adipogenesis in 3T3-L1 cells in a HIF-independent manner.

Obesity is a risk factor for many diseases including diabetes, cancer, cardiovascular disease, and chronic kidney disease. Obesity is characterized by the expansion of white adipose tissue (WAT). Hypertrophy and hyperplasia of adipocytes cause tissue hypoxia followed by inflammation and fibrosis. Its trigger, preadipocyte differentiation into mature adipocytes, is finely regulated by transcription factors, signal molecules, and cofactors. We found that echinomycin, a potent HIF-1 inhibitor, completely inhibited adipogenesis in 3T3-L1 WAT preadipocytes by affecting the early phase of mitotic clonal expansion. The dose required to exert the effect was surprisingly low and the time was short. Interestingly, its inhibitory effect was independent of HIF-1 pathways. Time-course DNA microarray analysis of drug-treated and untreated preadipocytes extracted a major transcription factor, CCAAT/enhancer-protein ß, as a key target of echinomycin. Echinomycin also inhibited adipogenesis and body weight gain in high fat diet mice. These findings highlight a novel role of echinomycin in suppressing adipocyte differentiation and offer a new therapeutic strategy against obesity and diabetes.

A New Analogue of Echinomycin and a New Cyclic Dipeptide from a Marine-Derived Streptomyces sp. LS298.

Quinomycin G (1), a new analogue of echinomycin, together with a new cyclic dipeptide, cyclo-(l-Pro-4-OH-l-Leu) (2), as well as three known antibiotic compounds tirandamycin A (3), tirandamycin B (4) and staurosporine (5), were isolated from Streptomyces sp. LS298 obtained from a marine sponge Gelliodes carnosa. The planar and absolute configurations of compounds 1 and 2 were established by MS, NMR spectral data analysis and Marfey's method. Furthermore, the differences in NMR data of keto-enol tautomers in tirandamycins were discussed for the first time. Antibacterial and anti-tumor activities of compound 1 were measured against 15 drug-sensitive/resistant strains and 12 tumor cell lines. Compound 1 exhibited moderate antibacterial activities against Staphylococcuse pidermidis, S. aureus, Enterococcus faecium, and E. faecalis with the minimum inhibitory concentration (MIC) values ranged from 16 to 64 µg/mL. Moreover, it displayed remarkable anti-tumor activities; the highest activity was observed against the Jurkat cell line (human T-cell leukemia) with an IC50 value of 0.414 µM.

Echinomycin decreases induction of vascular endothelial growth factor and hepatocyte regeneration in acetaminophen toxicity in mice.

Up-regulation of vascular endothelial growth factor (VEGF) is important to hepatocyte regeneration in the late stages of acetaminophen (APAP) toxicity in the mouse. This study was conducted to examine the relationship of hypoxia-inducible factor 1α (HIF-1α) to VEGF and hepatocyte regeneration in APAP toxicity using an inhibitor of HIF-1α DNA-binding activity, echinomycin (EC). B6C3F1 male mice were treated with APAP (200 mg/kg IP), followed by EC (0.15 mg IP) and killed at 4 hr. Serum alanine aminotransferase (ALT), necrosis, hepatic glutathione (GSH) and APAP protein adducts were comparable in the APAP/EC and the APAP/veh mice at 4 hr. Additional studies showed that high dose EC (0.3 mg) reduced hepatic VEGF but also lowered hepatic GSH. Subsequent studies were performed using the 0.15-mg dose of EC. Although EC 0.15 mg had no effect on hepatic VEGF levels at 8 hr, by 24 hr VEGF levels were decreased by 40%. Toxicity (ALT and histopathology) was comparable in the APAP and APAP/EC groups at 24 and 48 hr. Proliferating cell nuclear antigen expression was reduced by both Western blot analysis and immunohistochemical staining in the APAP/EC mice at 48 hr. The data support the hypothesis that induction of HIF-1α, its binding to DNA and subsequent expression of VEGF are important factors in hepatocyte regeneration in APAP toxicity in the mouse.

Drug release from a chemically-anchored PEG/phospholipid monolayer onto polymer-coated metallic stents.

We have prepared a covalently-grafted phsopholipid/PEG mixed monolayer onto drug-loaded polymercoated stainless-steel stents by in situ polymerization. To introduce a biocompatile surface on the stent surface, AcPC (1-palmitoyl-2-[12-(acryloyloxy)dodecanoyl]-sn-glycero-3-phosphocholine) and AcPEG (12-(acryloyloxy)dodecanoyl-poly(ethylene glycol)) were synthesized by modifying phospholipid and PEG with 12-(acryloyloxy)-1-dodecanoic acid and 12-(acryloyloxy)-1-dodecanol, respectively. Also, an acrylated co-polymer was synthesized by the acrylation of poly(octadecyl acrylate-co-hydroxybutyl acrylate, poly(OA-co-HA)) with acryloyl chloride, and poly(OA-co-HA) loaded with a hydrophobic drug, echinomycin, was coated on the stent surface using a spray coating system. In situ polymerization was carried out at the interface between a pre-assembled AcPC/AcPEG mixture and the enchinomycin-loaded acrylated co-polymer-coated stainless steel (Pol-SS). The physicochemical properties of a covalently-grafted phsopholipid/PEG mixed monolayer onto the drug-loaded polymer-coated stainless-steel stents were evaluated using water contact angle, field-emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). The data confirmed a successful phsopholipid/PEG monolayer grafting on the stents surface. The drug-release profile showed a sustained and controllable release pattern by the top-coated stents, achieved by adjusting the amount of loaded drug.

The short-term effects on restenosis and thrombosis of echinomycin-eluting stents topcoated with a hydrophobic heparin-containing polymer.

Although drug-eluting stents (DESs) have become the most effective means of treating coronary artery disease, safety concerns regarding their thrombogenicities remain to be surmounted. Here, we report on a novel type of DES capable of preventing restenosis and thrombosis. The DES was prepared by coating a bare metal stent with echinomycin (an anti-proliferative drug) in polyurethane by a spray drying method. Hydrophobic heparinized polymer was then topcoated onto stent over echinomycin/PU layer by dipping to improve hemocompatibility. The two-layered stent was characterized regarding surface and cross-sectional morphology, drug release pattern, platelet adhesion in vitro, and restenosis in vivo. It was found that the heparin topcoat acts as a diffusion barrier that allows the controlled release of drug in a sustained manner. Also, the heparin coated layer effectively reduced platelet adhesion, indicating excellent hemocompatibility. From the animal test using pigs, it was evident that the developed DESs can minimize neointimal proliferation and thrombus formation. The devised hydrophobic heparinized polymer-coated DES effectively reduced both restenosis and thrombosis, suggesting that they have potential as tools for the treatment of coronary artery diseases.

A randomized phase II trial of echinomycin, trimetrexate, and cisplatin plus etoposide in patients with metastatic nonsmall cell lung carcinoma: an Eastern Cooperative Oncology Group Study (E1587).

BACKGROUND: Patients with metastatic nonsmall cell lung carcinoma (NSCLC) usually have a poor prognosis. A chemotherapy regimen containing cisplatin is commonly used for symptom palliation. Echinomycin is a potent bifunctional intercalator of double-strand DNA; trimetrexate is a new derivative of methotrexate and is active against methotrexate-resistant tumor cells in vitro. METHODS: The Eastern Cooperative Oncology Group conducted a randomized Phase II study. Eligible patients were assigned to receive echinomycin 1200 microg/m2 by intravenous (i.v.) infusion over 30-60 minutes once a week for 4 weeks, repeated every 6 weeks; trimetrexate 12 mg/m2 i.v. bolus on Days 1-5 every 3 weeks, or 8 mg/m2 i.v. bolus on Days 1-5 for patients who had prior radiation to greater than 30% of their bone marrow; or cisplatin 60 mg/m2 i.v. on Day 1 and etoposide 120 mg/m2 i.v. on Days 1-3 every 4 weeks. Patients were evaluated before each cycle for tumor response, toxicity, and quality-of-life measurements. RESULTS: One hundred thirty-six patients were entered on the study, and 118 were evaluable for toxicity and response. The response rates were 16%, 5%, and 5% in patients treated with cisplatin and etoposide, echinomycin, and trimetrexate, respectively. There were no complete responses. The median survival was 37.9, 24.3, and 28.0 weeks for patients who received cisplatin and etoposide, echinomycin, and trimetrexate, respectively. Although cisplatin and etoposide appeared to give better therapeutic results, the response rate or survival did not reach statistical significance. This may have been due to inadequate sample size. Neither did quality-of-life measurement show any significant differences among treatments. CONCLUSIONS: Echinomycin and trimetrexate had minimal antitumor activity in patients with metastatic NSCLC: Response rate and survival remained poor in all three treatment arms. Patients should be encouraged to participate in clinical trials so that more effective therapy can be identified.

A phase II clinical trial of echinomycin in metastatic soft tissue sarcoma. An Illinois Cancer Center Study.

Echinomycin, a cyclic peptide in the family of quinoxaline antibiotics, was evaluated in patient with metastatic, soft tissue sarcoma not previously treated for metastatic disease. The starting dose of echinomycin was 1,200 mcg/m2 administered intravenously, once weekly x 4, followed by a two-week break. The protocol design called for dose escalation on subsequent cycles of therapy, but because of significant toxicity, dose escalation occurred in only 5 of 25 treatment cycles. Severe nausea and vomiting was the most common toxicity. No clinical responses were observed in the 12 evaluable patients. Echinomycin at this dose and schedule is inactive in metastatic soft tissue sarcoma.

Echinomycin (NSC 526417) in recurrent and metastatic squamous cell carcinoma of the cervix. A phase II trial of the Gynecologic Oncology Group (GOG).

Nineteen evaluable patients with recurrent or metastatic squamous cell carcinoma of the uterine cervix were treated with 1,500 micrograms/m2 of echinomycin every 4 weeks. No patient had received prior chemotherapy. There was one partial response (5% response, 95% confidence interval for response of 0% to 26%). The major toxicity was nausea and vomiting which was moderate to severe in six patients. Myelosuppression was not observed. Echinomycin, in this dose and schedule displays no major activity in chemotherapy-naive patients with advanced squamous-cell carcinoma of the cervix.

Phase II trial of echinomycin in advanced soft tissue sarcomas. A Southwest Oncology Group study.

Thirty-four patients with advanced soft tissue sarcomas were entered in a phase II trial of echinomycin. Patients received 1.2 mg/m2 intravenously (i.v.) weekly times four followed by a two week rest period. There were no objective responses. Dose limiting toxicity was gastrointestinal. Echinomycin given on this weekly schedule is inactive in treating previously treated patients with advanced soft tissue sarcomas.

Echinomycin (NSC 526417) in advanced ovarian cancer. A phase II trial of the Gynecologic Oncology Group.

Twenty-two patients with recurrent carcinoma of the ovary progressive after initial chemotherapy (21 with cisplatin-based treatment) were entered on a phase II trial utilizing Echinomycin at a dosage of 1,500 micrograms/m2 every 4 weeks. There were two complete responders and no partial responders (9% response, 95% confidence intervals for complete and partial responses of 1-29%). Major toxicity was modest and consisted mainly of nausea and vomiting. Echinomycin displays minimal activity as salvage therapy in women with advanced ovarian cancer at this dose and schedule.

Phase I trial of echinomycin (NSC 526417), a bifunctional intercalating agent, administered by 24-hour continuous infusion.

Echinomycin was administered to 43 patients with advanced cancer in escalating doses ranging from 60 to 2128 mcg/m2. The dose-limiting toxicity of echinomycin administered as a 24-h continuous infusion every 28 days was nausea and vomiting beginning at the end of the 24 h infusion and lasting from 3 to 8 days. Other toxicities included sporadic thrombocytopenia and biochemical evidence of liver dysfunction characterized by elevations in SGOT. Peripheral vein phlebitis was noted in 100% of patients, and watery diarrhea of 24-48-h duration was noted in 7% of patients. The maximally tolerated dose of echinomycin was 2128 mcg/m2. The recommended dose for phase II trials utilizing the 24-h continuous infusion schedule is 1600 mcg/m2 repeated every 28 days with pretreatment antiemetics.

Phase I study of echinomycin administered on an intermittent bolus schedule.

We have conducted a phase I study of the cyclic peptide echinomycin (Quinomycin A) on a schedule of administration of once every 4 weeks. Ten dose levels between 20 and 1800 micrograms/m2 were studied. Acute gastrointestinal toxicity, thrombocytopenia, and transient elevations of serum transaminases occurred at doses of greater than or equal to 1000 micrograms/m2. Gastrointestinal toxicity was severe and dose-limiting in several patients at doses of 1800 micrograms/m2. Thrombocytopenia was erratic, but generally increased with drug doses. Platelet count nadirs occurred 5-10 days after administration. Hepatic toxicity was reflected in transient elevations of serum transaminases without hyperbilirubinemia. Three patients experienced apparent anaphylactic reactions to doses of 1500 micrograms/m2. The maximum tolerated single dose of echinomycin was 1800 micrograms/m2. A starting phase II dose of 1500 micrograms/m2 is recommended.

[Study of the toxicity and antiblastoma activity of antibiotics echinomycin and 6270 in complexes with DNA]. / Izuchenie toksichnosti i antiblastomnoi aktivnosti antibiotikov ékhinomitsina i 6270 v kompleksakh s DNK.

Studies with the use of intact inbred albino mice showed that in intravenous administration the acute toxicity of antibiotic No. 6270 and echinomycin in complexes with DNA increased 3--4 times as compared to the toxicity of the same antibiotics used without the complex. Under the experimental conditions with 3-fold intravenous administration at 72-hour intervals in doses equivalent by their acute toxicity, the antitumor activity of the echinomycin complex with DNA against the solid form of lymphosarcoma L10-1 was approximately 4 times lower than the activity of the antibiotic used alone. Like echinomycin, antibiotic No. 6270 in complex with DNA used according to the same administration scheme in doses equivalent by their acute toxicity had a lower inhibitory effect on growth of lymphosarcoma L10-1 and sarcoma 180 as compared to its use alone.