Gene Therapy and Modification as a Therapeutic Strategy for Cancer

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Ahsen Tahir Chaudhry
Daud Akhtar


Gene therapy is an exciting new field of personalized medicine, allowing for medical procedures that can target diseases such as cancer in novel ways. Technologies that involve gene transfer treatments allow for the insertion of foreign DNA into tumour cells, resulting in restored protein expression or altered function. Gene therapy can also be used as a form of immunotherapy, either by modifying cancer cells to make them better targeted by the immune system, or by modifying the body’s immune cells to make them more ag­gressive towards tumours. Additionally, oncolytic virotherapy uses classes of genetically modified viruses that can specifically target and interfere with tumour cells. The ongoing development of the CRISPR/Cas9 gene editing tool may also have promise in future therapeutic applications, with the tool being capable of removing cancer-causing, latent viral infections, such as HPV, from afflicted cells. Nonetheless, there are still many questions of safety, efficacy, and commercial viability which remain to be resolved with many gene therapy procedures. There is also emerging controversy over the ethical, legal, and moral implications that modifying the genetic content of human beings will have on society. These concerns must be confronted and addressed if the benefits promised by gene therapy are to be properly realized.


La thérapie génétique est un nouveau domaine d’étude médicale personnalisée qui permet de cibler des maladies spécifiques comme le cancer de façon innovatrice. Cette thérapie utilise le transfert de gènes avec une insertion d’ADN étrangère dans les cellules can­céreuses dans le but de restaurer l’expression des protéines et de retrouver la fonction cellulaire. La thérapie génétique peut aussi être utilisée comme une forme d’immunothérapie, soit en modifiant les cellules cancéreuses pour qu’elles soient mieux ciblées par le système immunitaire ou en modifiant les cellules immunitaires du corps pour les rendre plus agressives envers les tumeurs. De plus, une virothérapie oncolytique utilise des virus génétiquement modifiés qui peuvent cibler spécifiquement et interférer avec des cellules cancéreuses. Le développement du système d’édition génétique CRISPR/Cas9 s’avère prometteur pour les applications thérapeutiques futures. Cet outil est capable d’enlever les infections virales latentes dans les cellules affectées qui peuvent causer le cancer, tel que l’HPV. Malgré ces découvertes, plusieurs questions importantes demeurent quant à la sécurité et à l’efficacité de leur application. Il s’agit d’un domaine controversé avec des implications éthiques, légales, et morales, car le tout implique une modification du contenu génétique humain. Ces inquiétudes doivent être adressées afin de pouvoir continuer à explorer les bienfaits de cette thérapie géné­tique. En poursuivant la recherche dans ce domaine, il serait possible de valider cette thérapie et optimiser ses bienfaits.

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