CCMB: novel drug delivery for breast and colon cancers

In the quest for non-toxic and targeted cancer therapy with no side effects, scientists have demonstrated the efficacy of a novel drug delivery system, using a combination of RNAi and nanotechnology for breast and colon cancers.

With RNAi technology paving the way for suppression of genes implicated in many cancers, specific and and effective mode of drug delivery to the targeted tumour was essential for a successful therapy.

The study led by Dr. Lekha Dinesh Kumar and her group from Centre for Cellular and Molecular Biology, Hyderabad, in collaboration with The University of Western Australia, European Cancer Stem Cell Research Institute, Cardiff University and Regional Cancer Centre, Thiruvananthapuram, demonstrated the successful in-site delivery of an anticancer biological drug (c-Myc) against breast and colorectal cancers using multimodal nanoparticles as the novel drug delivery system.

Holding the potential for translation from bench to bedside in cancer therapy, the biological drugs showed effective accumulation to therapeutic levels, thereby triggering the inhibition of neo-plastic spread. The effectiveness of the therapy and the method was validated in vivo by tumour suppression in two knockout mouse cancer models.

Following a daily dose of intra-tumour treatment with multimodal nanoparticles conjugated to the RNAi tool (c-Myc shRNA), it was found that the tumour growth was arrested and the animal survival increased in breast tumour models. Similarly, oral delivery of the same drug to colon cancer model mice showed that it not only increased the animals’ survival but also reversed the cancerous state of the intestinal tissue to a non-cancerous state.

“This study demonstrates, through careful design of non-viral nanoparticles and appropriate selection of therapeutic gene targets, that RNAi technology can be made an affordable and amenable therapy for cancer,” observed the authors of the study, which was published in May, 2015 in Molecular Cancer Therapeutics.

According to Dr. Lekha, Principal Scientist and Project Leader, Cancer Biology, CCMB, unlike the chemo-drugs which do not distinguish between normal and cancerous cells, the biological drug used by them specifically shuts down the gene implicated in cancer. Describing their work as proof of concept, which could be applied to different types of cancers, she said “this type of biological drug is going to be the future for cancer therapeutics which might eventually replace chemo-drugs.”

Dr. Lekha said that her division would soon start work on biological drugs for inhibiting tyrosine kinases which are the targets of the present chemo-drugs. This could revolutionise cancer therapy from general to more specific molecular treatments in future, she added.