Drug repurposing as a potential source of innovative therapies in cervical cancer.

OBJECTIVE: Drug repurposing is an alternative development pathway that utilizes the properties of drugs approved for other diseases and builds on available safety and pharmacological data to develop the drug as a potential treatment for other diseases. A literature-based approach was performed to identify drug repurposing opportunities in cervical cancer to inform future research and trials. METHODS: We queried PubMed for each drug included in two databases (ReDO_DB and CDcervix_DB, which include 300+ non-cancer drugs and 200+ cancer drugs not used in cervical cancer, respectively) and manually assessed all abstracts for relevance and activity in cervix cancer, and type of evidence. Subsequently, we also performed a search of clinical trial databases where we generated a list of registered trials in cervical cancer with all drugs from our databases. RESULTS: Of the 534 drugs from both databases, 174 (33%) had at least one relevant abstract or registered trial in cervical cancer. 94 (18%) drugs had at least human data available, and 52 (10%) drugs were evaluated in registered trials. To prioritize drugs to consider for future trials, all 174 drugs were further assessed for strength of scientific rationale, feasibility for integration in cervical cancer standard of care, evidence of radiosensitization, and potential mechanism of action. Out of the 174 drugs, 38 (22%) potential drug candidates were selected. CONCLUSION: This study resulted in a list of candidate drugs for potential evaluation in cervical cancer. Many drugs might warrant additional (pre)clinical investigation, which could be done in a coordinated manner using platform trials.

An Open Access Database of Licensed Cancer Drugs.

A global, comprehensive and open access listing of approved anticancer drugs does not currently exist. Partial information is available from multiple sources, including regulatory authorities, national formularies and scientific agencies. Many such data sources include drugs used in oncology for supportive care, diagnostic or other non-antineoplastic uses. We describe a methodology to combine and cleanse relevant data from multiple sources to produce an open access database of drugs licensed specifically for therapeutic antineoplastic purposes. The resulting list is provided as an open access database, (http://www.redo-project.org/cancer-drugs-db/), so that it may be used by researchers as input for further research projects, for example literature-based text mining for drug repurposing.

Coadministration of a Gloriosa superba extract improves the in vivo antitumoural activity of gemcitabine in a murine pancreatic tumour model.

BACKGROUND: Gloriosa superba L. (glory lily, Colchicaceae) contains colchicine, and related alkaloids such as 3-O-demethylcolchicine and its glycoside colchicoside. Previously the in vivo efficacy of a crude extract and a colchicine-poor / colchicoside-rich extract of G. superba seeds was shown in a murine model of pancreatic adenocarcinoma. HYPOTHESIS/PURPOSE: The efficacy can be improved without obvious signs of toxicity by increasing the treatment dose; the efficacy of gemcitabine can be improved by coadministration of a Gloriosa superba extract. STUDY DESIGN: A survival experiment was carried out in a murine model of pancreatic adenocarcinoma and the semi-long-term toxicity of both G. superba extracts was determined; a combination therapy with gemcitabine was evaluated. METHODS: A crude ethanolic extract (GS) and a colchicine-poor / colchicoside-rich extract (GS2B) were prepared, containing 3.22% colchicine, 2.52% colchicoside and 1.52% 3-O-demethylcolchicine (GS), and 0.07%, 2.26% and 0.46% (m/m) (GS2B). They were evaluated in a murine model of pancreatic adenocarcinoma at a dose of 4.5mg/kg (p.o., daily) total content of colchicine and derivatives during 3 weeks, or at 3.0mg/kg (p.o., daily) combined with gemcitabine (60mg/kg, i.p., 3x/week) during 54 days. RESULTS: A significant effect in tumour growth over time was observed for gemcitabine and the combination therapy compared to the control group. No significant difference was observed for the groups treated with colchicine and both extracts. However, combination therapy was significantly better than the monotherapy with gemcitabine. Moreover, survival analysis showed a significant prolongation of the survival of the groups treated with gemcitabine and the combination therapy. A slight difference in survival was observed between gemcitabine and the combination therapy, the latter one being slightly better. No significant prolongation of survival was observed for the extracts and colchicine compared to the control group. CONCLUSION: Although a relevant tumour growth inhibition and a difference of relative tumour volume compared to the control group were observed on day 11, and a slightly longer survival was noticed for GS2B, the most important conclusion from this study is that the crude G. superba extract (GS) might have an added value combined with gemcitabine in the treatment of pancreatic tumours.

In vitro and in vivo investigations on the antitumour activity of Chelidonium majus.

BACKGROUND: Chelidonium majus L. (Papaveraceae) (greater celandine) is a medicinal herb that is widely spread in Europe. Antitumoural activity has been reported for C. majus extracts. HYPOTHESIS/PURPOSE: To investigate the antitumour activity of a C. majus extract in vitro and in vivo. STUDY DESIGN: Cytotoxic effects of C. majus extracts were evaluated on human cancer cell lines, i.e. PANC-1 (pancreas cancer), HT-29 (colon cancer), MDA-MB-231 (breast cancer), PC-EM005 and PC-EM002 (primary endometrium cancer cells), and PANC02 (murine pancreatic adenocarcinoma cells). A preliminary in vivo study was performed to evaluate the effect of a defatted C. majus extract and Ukrain(TM) in a highly metastatic murine pancreatic model. METHODS: Chelidonium majus L. herb containing 1.26% (dry weight) of total alkaloids expressed as chelidonine was used to prepare an 80% ethanolic extract (CM2). This crude extract was then defatted with n-hexane, resulting in a defatted C. majus extract (CM2B). Cytotoxic effects of the two extracts (CM2 and CM2B) were evaluated on human and murine cell lines in vitro. CM2B and Ukrain(TM) were evaluated in a highly metastatic murine pancreatic model. RESULTS: Four main benzylisoquinoline alkaloids were identified in CM2B, i.e. chelidonine, sanguinarine, chelerythrine and protopine, using HPLC-UV. CM2 showed a high cytotoxic activity against PANC-1 (IC50, 20.7 µg/ml) and HT-29 (IC50, 20.6 µg/ml), and a moderate cytotoxic activity against MDA-MB-231 (IC50, 73.9 µg/ml). CM2 as well as CM2B showed a moderate to high cytotoxic activity against the PANC02 cell line (IC50, 34.4 and 36.0 µg/ml). Low to almost no cytotoxic effect was observed on primary endometrium cancer cells PC-EM005, PC-EM002 and on normal fibroblast cells 3T3, when treated with CM2B. Significantly less metastases were counted in mice treated with 1.2 mg/kg CM2B, but not with 3.6 mg/kg Ukrain(TM), compared to the control group. The extract, however, did not affect the weight of the primary tumours.