Development of tumour-targeted gene delivery systems for intravenous cancer therapy

Lead Research Organisation: University of Strathclyde
Department Name: Inst of Pharmacy and Biomedical Sci

Abstract

Cancer kills more people in the UK than any other disease: one cancer sufferer dies every 15 minutes, which adds up to over 35 000 people a year.
The possibility of using genes as medicines to treat cancer is currently limited by the lack of safe and efficacious delivery systems able to deliver therapeutic genes selectively to tumours by intravenous administration, without secondary effects to healthy tissues.
On the basis that iron is essential for tumour cell growth and can be effectively carried to tumours by using specific iron-carrier receptors present in abundance on the surface of cancer cells, we demonstrated that the use of iron-carriers linked to a highly promising gene delivery system resulted in gene expression mainly in the tumours after intravenous administration. This led to a rapid and sustained tumour regression over one month, with disappearance of 90% of the tested tumours and regression of the remaining ones in a laboratory model.
Building on the promising results already obtained, the proposed project aims to develop new "seek-and-destroy" systems by modifying the iron-carrier, and to evaluate their anti-cancer efficacy on cancer cells in vitro and in vivo after intravenous administration.
This innovative research would potentially have a major impact on healthcare, as there is currently no gene medicine commercially available for the intravenous treatment of cancer.

Technical Summary

The possibility of using genes as medicines to treat cancers is currently limited by the inability to efficiently deliver therapeutic genes to remote tumours by intravenous administration, without secondary effects to healthy tissues.
With the long-term aim of developing an efficacious cancer-targeted gene medicine, we demonstrated that polypropylenimine dendrimers conjugated to transferrin, whose receptors are overexpressed on most cancers, were highly promising, tumour-selective gene delivery systems : their intravenous administration to tumour-bearing mice led to a rapid and sustained tumour regression over one month, with disappearance of 90% of the tested tumours and regression of the remaining ones for the cancer model tested. This treatment was well tolerated by the animals.
Building on the promising results already obtained, the proposed project aims to develop new "seek-and-destroy" systems, by modifying the tumour targeting functionalities of the dendrimers as follows:
1) Replacement of the transferrin moiety by other promising tumour-targeting ligands of the same family that have intrinsic antitumoral activity, such as lactoferrin, lactoferricin and Beta-35.
2) Preparation of bifunctional dendrimers: conjugation of transferrin and lysine, conjugation of transferrin and transforming growth factor alpha.

The tumour targeting and therapeutic efficacy of these dendrimers will be evaluated on various cancer models, in vitro and in vivo after intravenous administration.

Planned Impact

- Cancer patients
Cancer kills more people in the UK than any other disease: one cancer sufferer dies every 15 minutes, which adds up to over 35 000 people a year.
The proposed research will address the unmet need of tumour-targeted delivery of plasmid DNA by intravenous administration, which is currently the subject of much research worldwide. Numerous highly promising therapeutic genes cannot be used clinically because of their failure to specifically reach remote tumours by intravenous administration. This represents a frustrating impasse, resulting in many potentially life-saving therapeutics being unavailable until this delivery issue is solved. The impact of our proposed project is therefore likely to be significant.

- Pharmaceutical industry
The pharmaceutical industry will be another beneficiary from this research, as this project aims to tackle a scientific challenge with direct relevance to patient treatment. The development of a safe and efficacious non-viral gene medicine able to specifically target and treat tumours after intravenous administration would have a major impact on healthcare. World gene therapy market is rapidly expanding and is forecast to reach $ 484 million by 2015. However, it is still in the experimental stage with success yet to be achieved in developing completely curative therapeutic drugs. To date, only two anti-cancer gene medicines, Gendicine and H101 are commercially available. These two p53 tumour-suppressor gene medicines are delivered in a viral vector for the intratumoral treatment of head and neck squamous cell carcinoma, in conjunction with chemotherapy and/or radiotherapy. There is currently no gene medicine commercially available for the intravenous treatment of cancer, thus making the development of an intravenously administered tumour-targeted gene medicine particularly promising. The proposed project is expected to improve the efficacy of intravenously administered gene therapy to tumours, leading to better anti-cancer therapy.

- Academia
As detailed in "Academic beneficiaries", the proposed project will be of interest to many multidisciplinary researchers. The information we obtain from this project will be shared with the scientific community by means of publication in scientific journals and presentation at conferences.

- National Health Service (NHS)
The Department of Health gives the total cost of treating cancers as £5.13 billion in 2008-2009, which accounts for 5.3% of total NHS spending during this year. In the very long term, targeted gene therapy with the ability to effectively treat cancer would have a pronounced impact on the significant financial burden caused by cancer patients on the NHS.

Publications

10 25 50
 
Description Member of the MPharm management Committee
Geographic Reach Local/Municipal/Regional 
Policy Influence Type Influenced training of practitioners or researchers
 
Description Trustee of the British Society of Nanomedicine
Geographic Reach National 
Policy Influence Type Influenced training of practitioners or researchers
 
Description Research grant
Amount £88,824 (GBP)
Funding ID ACC/KWF/CT04 
Organisation University of St Andrews 
Department The Cunningham Trust
Sector Charity/Non Profit
Country United Kingdom of Great Britain & Northern Ireland (UK)
Start 05/2012 
End 04/2014
 
Description Research grant
Amount £131,584 (GBP)
Funding ID R463/0216 
Organisation The Dunhill Medical Trust 
Sector Charity/Non Profit
Country United Kingdom of Great Britain & Northern Ireland (UK)
Start 05/2016 
End 04/2019
 
Description Research grant
Amount £166,888 (GBP)
Funding ID 16-1303 
Organisation World Cancer Research Fund 
Sector Charity/Non Profit
Country Global
Start 06/2016 
End 05/2019
 
Description Research grant
Amount £35,035 (GBP)
Funding ID ACC/KWF/CT11/ 04 
Organisation University of St Andrews 
Department The Cunningham Trust
Sector Charity/Non Profit
Country United Kingdom of Great Britain & Northern Ireland (UK)
Start 05/2014 
End 04/2015
 
Title Synthesis of novel lactoferrin- and lactoferricin-conjugated polypropylenimine dendrimers 
Description Lactoferrin- and lactoferricin-conjugated diaminobutyric polypropylenimine dendrimers (DAB-Lf and DAB-Lfc) are novel tumour-targeted gene delivery systems. Lactoferrin and lactoferricin are iron-binding members of the transferrin family, able to bind the transferrin receptors. In addition to their tumour delivery properties, these iron-carriers have recently been shown to have anti-cancer properties themselves, which make them highly attractive as part of a gene medicine. These 2 novel dendrimers have demonstrated their ability to carry DNA by formation of complexes, which occurred almost instantaneously and was stable over at least 24h. In vitro transfection experiment revealed that the conjugation of Lf to DAB led to a significantly improved transfection compared to DAB-Tf on A431 carcinoma cells overexpressing transferrin receptors. A qualitative analysis of the targeting efficacy of these delivery systems by confocal microscopy revealed that the co-localization of fluorescently-labelled DNA in the nucleus was more pronounced after treatment with DAB-Lf dendriplex compared to unconjugated dendriplex. 
Type Of Material Technology assay or reagent 
Provided To Others? No  
Impact These tumour-targeted gene delivery systems are highly promising. Their anti-cancer activity is currently further investigated in our laboratory. The description of the preparation of these gene delivery systems will be made available to other researchers in publications. 
 
Title Database Novel lactoferrin- and lactoferricin-bearing gene delivery systems for intravenous cancer therapy 
Description The research database "Novel tumour-targeted gene delivery systems for intravenous cancer therapy" is available in "Knowledgebase", the public research portal of the University of Strathclyde. It allows the open access to the research data obtained during the study. These data have now been published and can be accessed by all researchers. 
Type Of Material Database/Collection of data 
Provided To Others? No  
Impact This database facilitates the sharing of data with other research groups wishing to know more about our research and working in complementary research areas. It also provides examples of improvements in animal welfare and in the replacement, refinement or reduction of animal use that are crucial in all the research that we have been/are doing. 
 
Description Electron microscopy analysis of tumour-targeted dendriplexes 
Organisation University of Glasgow
Country United Kingdom of Great Britain & Northern Ireland (UK) 
Sector Academic/University 
PI Contribution The aim of this project is to develop a novel gene-based therapeutic system able to specifically deliver therapeutic genes to tumours after intravenous administration, thus leading to an improved anti-cancer therapeutic effect without secondary effects to normal tissues. To do so, we proposed to synthesize lactoferrin- and lactoferricin-conjugated diaminobutyric polypropylenimine dendrimers, namely DAB-Lf and DAB-Lfc. We conjugated DAB dendrimer to the targeting ligands and characterized the resulting tumour-targeted dendrimers, but didn't have the electron microscopy facilities to visualize the dendriplexes.
Collaborator Contribution Mrs Margaret Mullin, from the University of Glasgow, took pictures of the dendriplexes by transmission electron microscopy, and confirmed their shape. She replaced Dr Lawrence Tetley, with whom we have been collaborating since 2008.
Impact This collaboration is extremely important for us, as it is crucial to confirm the spherical shape of the dendriplexes before determining their size by photon correlation spectroscopy, using a Zetasizer. It is a multidisciplinary collaboration involving researchers with electron microscopy and drug delivery expertise, and resulted in publications in Biomaterials (PMID: 21596431), Journal of Controlled Release (PMID: 21539872, PMID: 19944722, PMID: 19709637), Nanomedicine (PMID: 22891867) and Nanomedicine: Nanotechnology, Biology and Medicine (PMID: 21333755).
Start Year 2008
 
Description NMR analysis of the delivery systems 
Organisation University of Strathclyde
Department Strathclyde Institute of Pharmacy & Biomedical Sciences
Country United Kingdom of Great Britain & Northern Ireland (UK) 
Sector Academic/University 
PI Contribution The aim of this project is to develop a novel gene-based therapeutic system able to specifically deliver therapeutic genes to tumours after intravenous administration, thus leading to an improved anti-cancer therapeutic effect without secondary effects to normal tissues. To do so, we proposed to synthesize lactoferrin- and lactoferricin-conjugated diaminobutyric polypropylenimine dendrimers, namely DAB-Lf and DAB-Lfc. We conjugated DAB dendrimer to the targeting ligands, but didn't have the NMR skills to confirm the identity of the prepared compounds.
Collaborator Contribution Dr RuAngelie Edrada-Ebel, from the Strathclyde Institute of Pharmacy and Biomedical Sciences, confirmed by NMR the identity of the synthesized targeted dendrimers.
Impact This collaboration is extremely important for us, as it is crucial to confirm the identity of the synthesized compounds before further analyzing them in vitro and in vivo. It is multidisciplinary, involving researchers with analytical chemistry and drug delivery expertise, and led to publications in Biomaterials (PMID: 21596431), Journal of Controlled Release (PMID: 19944722) and Nanomedicine: Nanotechnology, Biology and Medicine (PMID: 21333755).
Start Year 2008
 
Title Targeted dendrimers 
Description With the long-term aim of developing an efficacious cancer-targeted gene medicine, we demonstrated that polypropylenimine dendrimers conjugated to transferrin, whose receptors are overexpressed on most cancers, were highly promising, tumour-selective gene delivery systems : their intravenous administration to tumour-bearing mice led to a rapid and sustained tumour regression over one month, with disappearance of 90% of the tested tumours and regression of the remaining ones for the cancer model 
IP Reference GB2487699 
Protection Patent application published
Year Protection Granted 2012
Licensed No
Impact These tumour-targeted gene delivery systems are highly promising and might have potential for the treatment of a wide range of cancers. Their anti-cancer activity is currently further investigated in our laboratory.
 
Title Synthesis of tumour-targeted gene delivery systems 
Description We have synthesized two novel tumour-targeted gene delivery systems, namely lactoferrin- and lactoferricin- bearing polypropylenimine dendrimers. These 2 novel dendrimers have demonstrated their ability to carry DNA by formation of complexes, which occurred almost instantaneously and was stable over at least 24h. In vitro transfection experiment revealed that the conjugation of Lf to DAB led to a significantly improved transfection compared to DAB-Tf on A431 carcinoma cells overexpressing transferrin receptors. A qualitative analysis of the targeting efficacy of these delivery systems by confocal microscopy revealed that the co-localization of fluorescently-labelled DNA in the nucleus was more pronounced after treatment with DAB-Lf dendriplex compared to unconjugated dendriplex. The conjugation of lactoferrin and lactoferricin to the dendrimer significantly increased the gene expression in the tumor while decreasing the non-specific gene expression in the liver. Consequently, the intravenous administration of the targeted dendriplexes encoding TNFa led to the complete suppression of 60% of A431 tumors and up to 50% of B16-F10 tumors over one month. The treatment was well tolerated by the animals. These results suggest that these novel lactoferrin- and lactoferricin-bearing dendrimers are promising gene delivery systems for cancer therapy. 
Type Therapeutic Intervention - Cellular and gene therapies
Current Stage Of Development Initial development
Year Development Stage Completed 2012
Development Status Under active development/distribution
Impact This research will address the unmet need of tumour-targeted delivery of plasmid DNA by intravenous administration, which is currently the subject of much research worldwide. Numerous highly promising therapeutic genes cannot be used clinically because of their failure to specifically reach remote tumours by intravenous administration. This represents a frustrating impasse, resulting in many potentially life-saving therapeutics being unavailable until this delivery issue is solved. The impact of our proposed project is therefore likely to be significant. This research is at the interface of cancer therapy and gene delivery. As a result, it will be of interest to the thousands of academics investigating these topics worldwide. This will include the scientists involved in cancer biology, gene delivery, biomaterials, pharmaceutics, as well as clinical oncologists. 
 
Description Invitation to give a talk at "Techfest in September" 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? Yes
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact My talk was very well received by members of the audience. It sparked questions and discussions afterwards for about one hour and should lead to further involvement in "Techfest in September" next year.

The feedback obtained by the organizers about my talk was very positive. I should be involved in "Techfest in September" next year.
Year(s) Of Engagement Activity 2014
URL http://www.techfestsetpoint.org.uk/tis/uploads/files/programmes/2014_TechFestPublicProgramme.pdf
 
Description Invited presentation at an international conference (10th International Conference and Exhibition on Pharmaceutics & Novel Drug Delivery Systems, London) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact I was invited to give an oral presentation at the 10th International Conference and Exhibition on Pharmaceutics & Novel Drug Delivery Systems, London (March 2017). It was attended by academics from my research field, researchers and students.
My presentation was very well received by colleagues and members of the audience. It should lead to new national collaborations, future work of new delivery systems and developed my international visibility amongst my colleagues.
Year(s) Of Engagement Activity 2017
 
Description Invited presentation at an international conference in China 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact I was invited to present my work at the 13th International Conference on Polymers for Advanced Technologies (PAT) 2015, Hangzhou, China (June 2015). It was attended by academics from my research field, researchers, students, as well as health professionals.
My presentation was very well received by colleagues and members of the audience. It should lead to international collaborations and developed my international visibility amongst my colleagues.
Year(s) Of Engagement Activity 2015
 
Description Invited presentation at an international conference in Greece 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact I was invited to present my work at the 9th International Conference of Anticancer Research, Sithonia, Greece (October 2014). My talk was entitled "Tumour regression after intravenous administration of novel tumour-targeted nanomedicines". It was attended by academics from my research field as well as health professionals.
My presentation was very well received by colleagues and members of the audience. It should lead to international collaborations and developed my international visibility amongst my colleagues.
Year(s) Of Engagement Activity 2014
 
Description Invited presentation at an international conference in Lithuania 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact I was invited to present my work at the International conference "From bench to bed: challenges in cancer care", dedicated to the 80th anniversary of Lithuanian Society of Oncology. It took place on September 20-21, 2013, in Druskininkai (Lithuania). My talk was entitled "Tumour regression after intravenous administration of novel tumour-targeted nanomedicines". It was attended by academics from my research field as well as health professionals.

My presentation was very well received by colleagues and members of the audience. It should lead to international collaborations and developed my international visibility amongst my colleagues.
Year(s) Of Engagement Activity 2013
URL http://www.lod-vuoi.lt/
 
Description Invited presentation at the Nano World Cancer Day 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact I was invited to present my work at the Nano World Cancer Day, London (February 2016). It was attended by academics from my research field, researchers, students, the press as well as health professionals.
My presentation was very well received by colleagues and members of the audience. It developed my visibility amongst my colleagues.
Year(s) Of Engagement Activity 2016
 
Description Invited seminar at Thammasat University, Bangkok, Thailand 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact I was invited to present seminar at Thammasat University, Bangkok, Thailand (December 2016). The seminar was attended by academics from my research field, researchers, students, as well as health professionals.
My presentation was very well received by colleagues and members of the audience. It should lead to international collaborations and developed my international visibility amongst my colleagues.
Year(s) Of Engagement Activity 2016
 
Description Involvement in the Glasgow Science Centre's Bodyworks exhibition 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact I was involved in the Strathclyde's Really Small Science nanobioengineering public engagement event that took place from Thursday 17th October until Sunday 20th October 2013 as part of the Glasgow Science Centre's Bodyworks exhibition. I designed and presented a Cancer targeting dart game, which attracted 1037 people (553 children and 484 adults).

My "Cancer targeting" exhibit was very well received by the public. We designed it in such a way that it was reachable to children of all ages, as well as adults: young children were more interested in throwing magnetic darts to the dart board, some older children were both interested by the game itself and the science behind the game, while most adults wanted to know more about the cancer-targeting nanomedicines designed in our laboratory at the University of Strathclyde. We made sure to involve all members of a same family in this exhibit: teams "adult-child" were made within a family, including young children (who were allowed to bring a "targeted nanomedicine" dart directly in the middle of the dart board with the help of their parents). In addition to the magnetic dart board, we used a flipchart to explain what "cancer targeting" is, using a simple example from every day's life understandable by everybody.
Year(s) Of Engagement Activity 2013
URL http://www.glasgowsciencecentre.org/
 
Description School visits as a Science, Technology, Engineering and Mathematics (STEM) Ambassador 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach Local
Primary Audience Schools
Results and Impact I volunteered to participate in two "Lab in a lorry" activities, in Lomond School (in Helensburgh) on Wednesday 7th November and in Notre Dame High School (in Greenock) on Wednesday 14th November. A total of 200 pupils attended these workshops, which sparked questions and discussions afterwards.

The feedback from the teachers was highly positive. The pupils involved in these workshops appeared to be highly interested in science.
Year(s) Of Engagement Activity 2012