Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0029463 (osteosarcoma)
16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Irinotecan (CPT-11) is a semi-synthetic derivative of camptothecin currently in clinical trials. In vitro, CPT-11 presented preferential cytotoxicity toward some solid tumor cells (mouse colon 38 and pancreas 03; human pancreas MIA PaCa-2) as compared to leukemia cells (L1210), whereas SN-38, a metabolite of CPT-11, was not solid tumor selective. In vivo, schedule of administration studies in P388 leukemia and mammary adenocarcinoma 16/C (MA16/C) showed that CPT-11 was not markedly schedule dependent. In order to determine its spectrum of anticancer activity, CPT-11 was evaluated against a variety of mouse and human tumors. The end points used were total log cell kill (Lck) for solid tumors and increase in life span (% ILS) for leukemia. Intravenous CPT-11 was found highly active against both early and advanced stage pancreatic ductal adenocarcinoma 03 (P03), with 60% long-term survivors and 100% complete regressions, respectively. Other responsive tumors included: colon adenocarcinomas 38 and 51 (both 1.0 Lck); MA16/C (3.4 Lck); MA13/C (1.0 Lck); human Calc18 breast adenocarcinoma (2.8 Lck); Glasgow osteogenic sarcoma (1.8 Lck); Lewis lung carcinoma (1.4 Lck); B16 melanoma (1.4 Lck); P388 leukemia (170% ILS) and L1210 leukemia (64% ILS). Of interest, CPT-11 was active against tumors with acquired resistance to vincristine (P388/Vcr), to doxorubicin (P388/Dox) and to docetaxel (Calc18/TXT). CPT-11 was also found highly active after oral administration in mice bearing P03 and MA16/C tumors. Pharmacokinetic evaluations performed i.v. at the highest non-toxic dosage in mice bearing P03 tumors revealed CPT-11 peak plasma concentrations (Cmax) of 8.9 micrograms/ml and a terminal half-life of 0.6 h. The metabolite SN-38 plasma concentrations presented a Cmax of 1.6 micrograms/ml and a terminal half-life of 7.4 h. Although the CPT-11 tumor levels were similar to the plasma concentrations for early time points, drug levels decreased more slowly in the tumor compared to plasma (half-life, 5.0 h). SN-38 tumor levels reached concentrations in the range of 0.32-0.34 micrograms/g and decayed with a half-life of 6.9 h. No significant difference in plasma or tumor pharmacokinetics of either CPT-11 or SN-38 were noted after one or five daily i.v. injections. Overall, these data show that CPT-11 has good activity in experimental models, when administered both by the i.v. and the oral routes. Compared to humans, a similar schedule of administration independence was observed and similar CPT-11 levels could be reached at efficacious dosages although metabolite SN-38 levels were found higher in mice.
...
PMID:Experimental antitumor activity and pharmacokinetics of the camptothecin analog irinotecan (CPT-11) in mice. 882 13

The relevance of circadian rhythms in irinotecan and oxaliplatin tolerability was investigated with regard to antitumour activity. Mice bearing Glasgow osteosarcoma (GOS) received single agent irinotecan (50 or 60 mg kg(-1) per day) or oxaliplatin (4 or 5.25 mg kg(-1) per day) at one of six dosing times expressed in hours after light onset (3, 7, 11, 15, 19 or 23 hours after light onset). Irinotecan (50 mg kg(-1) per day) and oxaliplatin (4 or 5.25 mg kg(-1) per day) were given 1 min apart at 7 or 15 hours after light onset, or at their respective times of best tolerability (7 hours after light onset for irinotecan and 15 hours after light onset for oxaliplatin) or worst tolerability (15 hours after light onset for irinotecan and 7 hours after light onset for oxaliplatin). Tumour growth rate was nearly halved and per cent increase in estimated life span (% ILS) was - doubled in the mice receiving irinotecan at 7 hours after light onset as compared to 15 hours after light onset (P<0.05). Results of similar magnitude were obtained with oxaliplatin for both endpoints, yet with 7 hours after light onset corresponding to least efficacy and 15 hours after light onset to best efficacy (P<0.05). Irinotecan addition to oxaliplatin proved therapeutic benefit only if the schedule consisted of irinotecan administration at 7 hours after light onset and oxaliplatin delivery at 15 hours after light onset, i.e. when both drugs were given near their respective "best" circadian times. These would correspond to the middle of the night for irinotecan and the middle of the day for oxaliplatin in humans.
...
PMID:Circadian optimisation of irinotecan and oxaliplatin efficacy in mice with Glasgow osteosarcoma. 1195 36

The combination of irinotecan (daily for 5 days for 2 consecutive weeks) and ifosfamide (daily on days 1 through 3) was investigated in children with osteosarcoma. Irinotecan pharmacokinetic investigations were performed before ifosfamide (day 1), after 3 days of ifosfamide (day 3), and 9 days after the end of ifosfamide (day 12). On day 3, the concentrations of irinotecan's active metabolite, SN-38, were below the limit of quantitation in two patients and were decreased in a third patient. The SN-38 area under the concentration-time curve remained below the day 1 value in two patients on day 12. The reduced area under the curve to the active metabolite SN-38 during ifosfamide therapy predicts a compromised efficacy of irinotecan in this combination.
...
PMID:Effect of fractionated ifosfamide on the pharmacokinetics of irinotecan in pediatric patients with osteosarcoma. 1554 15

Long-term survival in patients with metastatic, relapsed, or recurrent Ewing sarcoma and rhabdomyosarcoma is dismal. Irinotecan, a topoisomerase 1 inhibitor, has activity in these sarcomas, but due to poor bioavailability of its active metabolite (SN-38) has had limited clinical efficacy. In this study we have evaluated the efficacy and toxicity of STA-8666, a novel drug conjugate which uses an HSP90 inhibitor to facilitate intracellular, tumor-targeted delivery of the topoisomerase 1 inhibitor SN-38, thus preferentially delivering and concentrating SN-38 within tumor tissue. We present in vivo evidence from mouse xenograft models that STA-8666 results in more persistent inhibition of topoisomerase 1 and prolonged DNA damage compared to irinotecan. This translates into superior antitumor efficacy and survival in multiple aggressive models of both diseases in mouse xenografts, as well as in an irinotecan-resistant model of pediatric osteosarcoma, demonstrated by dramatic tumor shrinkage, durable remission and prolonged complete regressions following short-term treatment, compared to conventional irinotecan. Gene expression analysis performed on xenograft tumors treated with either irinotecan or STA-8666 showed that STA-8666 affected expression of DNA damage and repair genes more robustly than irinotecan. These results suggest that STA-8666 may be a promising new agent for patients with pediatric-type sarcoma.
...
PMID:STA-8666, a novel HSP90 inhibitor/SN-38 drug conjugate, causes complete tumor regression in preclinical mouse models of pediatric sarcoma. 2760 46