• Immune cells

    The cells of the immune system involved in defending the body against infectious disease, foreign invaders and cancer cells. [Patient Resource LLC]

  • Immune checkpoint inhibitors

    Drugs that block the activation of specific immune checkpoint pathways. These drugs allow the immune system to ‘take the brakes off,’ which allows the immune system to recognize and attack cancer cells. [Patient Resource LLC]

  • Immune checkpoint pathways

    The system of checks and balances in place to prevent overactivation of the immune system. Different pathways function at different stages of the immune response to help regulate the length and intensity of T-cell activity; turning on an immune checkpoint typically results in shutting down the immune system response. [Patient Resource LLC]

  • Immune-related adverse events (IRAEs)

    Auto- immune reactions that occur as a result of boosting the immune system. Severe reactions may include colitis, dermatitis and hepatitis. [Patient Resource LLC]

  • Immunosuppression

    A condition in which the immune system is prevented from launching successful attacks to protect the body against infection and disease. [Patient Resource LLC]

  • Immunotherapy

    A treatment that uses certain parts of a person’s immune system to fight diseases such as cancer. This can be done in a couple of ways: stimulating your own immune system to work harder or smarter to attack cancer cells; giving you immune system components, such as engineered immune system proteins. Some types of immunotherapy are also sometimes called biologic therapy or biotherapy. [From]

    • Cold tumours: tumours that for various reasons contain few infiltrating T cells and are not recognized nor provoke a strong response by the immune system. This makes them difficult to treat with current immunotherapies.
    • Hot tumours: tumours where T cells are present and can be more easily mobilized against the cancer by current immunotherapies.

    Research is underway on how to enhance immunotherapy to activate the immune system to destroy cancer cells, thereby turning immunologically “cold” tumours into “hot” ones.

  • Implementation science

    The scientific study of methods and strategies that facilitate the uptake of evidence-based practice and research into regular use by practitioners and policymakers. The field of implementation science seeks to systematically close the gap between what we know and what we do (often referred to as the know-do gap) by identifying and addressing the barriers that slow or halt the uptake of proven health interventions and evidence-based practices. [From]

  • In silico

    Scientific experiments or research conducted or produced by means of computer modeling or computer simulation. Some examples:

    • automated testing of large numbers of chemical and/or biological compounds for a specific biological target (high-throughput screening for drug discovery)
    • data mining approaches used to analyze vast repositories of genetic data
    • computational approaches applied to understand and predict the complex dynamics of biological systems (computational biology)
  • In vivo

    In the body. In vivo studies are those conducted on living organisms.

  • Infectious agents

    Viruses, bacteria, and parasites that may cause cancer or increase the risk that cancer will form. Some viruses can disrupt signaling that normally keeps cell growth and proliferation in check. Some infections weaken the immune system, making the body less able to fight off other cancer-causing infections. And some viruses, bacteria, and parasites also cause chronic inflammation, which may lead to cancer. [From]

  • Informed Consent

    In any study involving humans, it is crucial that the participants voluntarily agree to take part in the research, and that they do so with a full understanding of their rights and the possible risks associated with participating in the study. Throughout the entire study, the researcher has an ethical obligation to share plain-language information with all participants that will enable them to give their free and informed consent. [CIHR]

  • Interferon

    A protein released by immune cells that helps regulate different immune cell activity; types of interferon include alpha, beta, gamma and lambda. Different types help regulate different functions, including prompting increased T-cell activity, stimulating natural killer cells or affecting certain cell functions that influence tumor cell growth. Laboratory-made versions of the IFN-alpha protein are currently FDA-approved to treat certain types of cancer. [Patient Resource LLC]

  • Interleukin

    A protein produced by cells of the immune system that helps regulate the production of certain immune cells, how they function during an immune response and their production of cytokines. The laboratory-made version of this protein, aldesleukin (Proleukin), is currently FDA-approved to treat metastatic melanoma and metastatic renal cell carcinoma (kidney cancer). [Patient Resource LLC]

  • Invasion/invasive cancer

    Cancer that has spread beyond the layer of tissue in which it developed and is growing into surrounding, healthy tissues. [NCI]

  • Investigational drug

    A drug that has been tested in the laboratory and has been approved by Health Canada for testing in people. Clinical trials test how well investigational drugs work and whether they are safe to use. An investigational drug may be approved by the Health Canada for use in one disease or condition but still be considered investigational in other diseases or conditions (off-label). Health Canada recently introduced a process for evaluating off-label use of authorized drugs in clinical trials. [See]