The Crucial Role of Patient Samples in Cancer Research

 

kevin-patient-sample-blog

Two HeLa cells, obtained using a scanning electron microscope. Source: National Institutes of Health (NIH).

Cancer research can take on many forms, and many major discoveries have been made using organisms such as roundworms, fruit flies, mice and rats. However, patients themselves play a crucial role in research, from participation in clinical trials to providing tumour samples for researchers to study. Perhaps the most famous example is the case of Henrietta Lacks, whose cervical cancer was used to create the first human “immortal” cell line in the 1950s (HeLa). This marked the first time researchers could grow human cells indefinitely in the lab. Armed with HeLa cells, it suddenly became possible for researchers to test different drugs on cancer cells to find those that worked, and to test how different genetic mutations change the cells’ behaviour to understand why cancers arise in the first place. Not only did Henrietta’s cells have major impacts in cancer research, HeLa cells greatly improved our understanding of human biology and other fields of medicine. In 1954, Jonas Salk used mass-produced HeLa cells to develop a polio vaccine that would go on to save countless lives.

 

Unfortunately, despite the numerous advances made using HeLa cells, the story of Henrietta Lacks now serves as a cautionary tale of what not to do with patient samples. Doctors never asked Henrietta’s consent to use her cells for research, nor were they under any obligation to tell her and her family what her cells would be used for.  After Henrietta passed away from her cancer, HeLa cells were used in thousands of research studies and commercialized to generate billions of dollars of revenue, and no one had bothered to tell Henrietta’s family what was going on. When the genetic sequence of HeLa cells was published in 2013, the authors of the paper did not even ask her family before making the information publicly available. Thankfully, recent efforts have been made to commemorate Henrietta’s contributions, and her descendants were able to decide what aspect of the information would become public.

Henrietta’s story has taught a valuable lesson to researchers and doctors about the importance of research ethics. Today, informed consent is an absolute requirement before patient samples are used in research. This means that not only does permission need to be obtained, but that the donor must be made fully aware of the potential uses of the sample for research, the potential privacy risks involved, and the potential benefits the research may bring forth for society. In a time when a person’s potential identity might be inferred from genetic information, these guidelines have never been more important.

Cancer is an immensely complex disease which differs greatly from person to person. Even two people with the same type of cancer can have tumours with completely different genetic mutations, making each tumour respond a different way to treatment. In order to really understand a given cancer type, researchers need to analyze hundreds, if not thousands of tumour samples. Compared to the 1950s, we now have access to much more advanced technologies in cancer research. Genetic sequencing is almost routine in the research lab, allowing us to obtain a full picture of a person’s genome and that of a patient’s tumour.

In a recent Toronto study, scientists used cancer cells from 78 patients to learn more about acute myeloid leukemia, a type of blood cancer that is very aggressive and is often resistant to therapy. In this study, they identified a set of genes that could predict response to standard therapy [Ng]. This information allowed them to develop a tool that can help determine a patient’s prognosis, guide treatment decisions, and even identify the patients most likely to benefit from new clinical trials. This new tool is incredibly cost-efficient and reliable, outperforms previous diagnostic tools, and has a turn-around time of less than 48 hours. Development of this diagnostic tool required a large sample size of human cancers, and therefore would not have been possible without the individual contributions of cancer patients to the study.

Studies like this one illustrate why using patient samples are so important in making advances in cancer research. Thankfully, lessons have been learned from the past and patients are willing to consent to scientific research to help future generations.

This article was written by Kevin Lan, who is currently finishing his PhD at the University of Toronto. He is studying how brain cancers become resistant to current cancer therapies. To learn more about Kevin and his research you can visit our members page.

Further reading:

The Immortal Life of Henrietta Lacks by Rebecca Skloot (Broadway Books)

Ng. et. al, A 17-gene stemness score for rapid determination of risk in acute leukaemia. http://www.nature.com/nature/journal/vaop/ncurrent/full/nature20598.html

http://www.thepmcf.ca/News-Media/Latest-News/2016/Princess-Margaret-experts-develop-new-test-for-leu

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s