Introduction to the Hallmarks of Cancer

A composite from a time-lapse of a HeLa cell (cervical cancer) undergoing cell division. Cellular structures have been visualized using cyan (cell membrane) and red (DNA). Image Credit: Kuan-Chung Su, London Research Institute, Cancer Research UK, Wellcome Images.

A composite from a time-lapse of a HeLa cell (cervical cancer) undergoing cell division. Cellular structures have been visualized using cyan (cell membrane) and red (DNA). Image Credit: Kuan-Chung Su, London Research Institute, Cancer Research UK, Wellcome Images.

In 2000, Robert Weinberg and Douglas Hanahan published a review article in the journal Cell titled The Hallmarks of Cancer. It was a seminal paper in every sense of the word; downloaded 20,000 times a year between 2004 and 2007, with over 15,000 citations in other research papers. In 2011, Weinberg and Hanahan updated their list by proposing four more new Hallmarks of Cancer, bringing up the list to Ten Hallmarks of Cancer. Why is this paper so important? Cancer, as we know by now, is an incredibly complicated disease.

A single tumor sample could have over a hundred different mutations; nearly one in every two hundred genes in the human genome. If two breast cancer specimens are compared, the set of mutated genes are far from identical. Every tumor is unique. Weinberg and Hanahan simplified this dauntingly complex disease to six underlying principles. The hugely complicated beast that is cancer, so diverse that even the same organ can have many different tumor types, was reduced to just six common traits that every single cancer shares, to facilitate that transformation from a normal cell to a cancer cell. It answers the ‘how does cancer happen’ question very elegantly, and we gain insight into all the different things that go wrong in a cancer cell.

However, the science is not accessible to the public because the molecular mechanisms described require a specialist knowledge in the field of cell biology. Over the coming weeks, I will go through each of these Hallmarks in detail. I will explain the normal processes that occur inside the cell and then explain what goes wrong with this process in a cancer cell.Cancer is so prevalent, and is a topic that we hear about on a daily basis. Cancer is also deeply personal; we know people who are directly affected by cancer, either themselves or a loved one. Not everyone has the knowledge to understand what is going on, and it can be very scary to hear the jargon from a doctor or an oncologist. To many people, cancer is the big scary ‘C-word’. Trying to research it online is not usually helpful, as even Wikipedia has a confusingly large amount of jargon. This series will address that knowledge gap. It will demystify cancer, and answer the question ‘why does cancer happen?’

The Hallmarks

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17 Responses

  1. Seo says:

    Thank you for this, its been really helpful for my Cellular Pathology exam revision 🙂

  2. Belques says:

    Thank you I want to ask about publishing my research in a scientific journal

  1. June 23, 2014

    […] ← Previous Next → […]

  2. June 23, 2014

    […] Read more Hallmarks of Cancer […]

  3. June 23, 2014

    […] The Hallmarks of Cancer are ten underlying principles shared by all cancers. The first and second Hallmark of Cancer articles can be found here and here. The Third Hallmark of Cancer is defined as “Evading Apoptosis”. Apoptosis is the opposite of cell growth; it is cell death. To divide and grow uncontrollably, a cancer cell not only has to hijack normal cellular growth pathways, but also evade cellular death pathways. Indeed, this acquired resistance to apoptosis is characteristic of all types of cancer. But before I explain how cancer cells do this, we need to understand how the process of cellular death occurs in a normal cell.The apoptotic program is hardwired into every single cell in our body. It is like a cyanide capsule, swiftly delivering death if the circumstances require cellular suicide. If a cell detects that it has damaged DNA, it can activate apoptosis to remove itself from the population. Apoptosis, or cellular suicide, is an entirely normal function of cells. The same apoptotic program is activated when a tadpole changes into a frog; the cells in the tail die through apoptosis, and the tail disappears. The same is true for the webbing between our fingers in our early embryonic development. Apoptosis is an extremely tidy process; cellular membranes are disrupted, the chromosomes are degraded, the DNA breaks up into fragments, and the dying, shrinking cell is swallowed up by a neighboring cell or a patrolling immune cell, leaving no trace of the cellular suicide behind. […]

  4. June 23, 2014

    […] underlying principles shared by all cancers. The previous Hallmark of Cancer articles can be found here. The Fourth Hallmark of Cancer is defined as “Limitless Replicative Potential”.The first three […]

  5. June 24, 2014

    […] The Hallmarks of Cancer focus on 10 underlying principles shared by all cancers. The Fifth Hallmark of Cancer is defined as “Sustained Angiogenesis.” In a developing embryo or a healing wound, communities of cells organize themselves into tissues, undertaking specialized tasks beyond the ability of any single cell to accomplish. These tissues require oxygen and nutrients, as well as a facility to remove metabolic wastes and carbon dioxide. The formation of new blood vessels, known as angiogenesis, satisfies these needs. In a similar manner, a growing tumor, an aggregation of cancer cells, also requires access to oxygen, nutrients and waste disposal. Beyond a certain size, typically 1 mm, diffusion alone is insufficient for providing these necessities; the surface area to volume ratio becomes too low and the developing tumor begins to starve. In response, cancer cells send out signals to the cells of nearby blood vessels, inducing these innocent bystanders to grow extensions to form a supply chain and drainage channels. Thus, cancer cells subvert these normal neighboring cells into playing a key role in driving tumor development. […]

  6. July 22, 2014

    […] The Hallmarks of Cancer are ten underlying principles shared by all cancers. You can read the first Hallmark of Cancer article here. The Second Hallmark of Cancer is defined as “Insensitivity to Antigrowth Signals”. Before I explain how failure to respond to antigrowth signals is closely involved in the development of cancer, it is useful to define and understand how cell division works. Cancer is, after all, the uncontrolled division of the cell; so we first need to understand how normal cell division is controlled through the cell cycle. […]

  7. July 22, 2014

    […] The Hallmarks of Cancer are ten underlying principles shared by all cancers. The Fourth Hallmark of Cancer is defined as “Limitless Replicative Potential”. […]

  8. July 22, 2014

    […] The Hallmarks of Cancer focus on 10 underlying principles shared by all cancers. The Fifth Hallmark of Cancer is defined as “Sustained Angiogenesis.” […]

  9. July 22, 2014

    […] The Hallmarks of Cancer focus on 10 underlying principles shared by all cancers. The eighth Hallmark of Cancer is defined as “tumor-promoting inflammation.” […]

  10. July 22, 2014

    […] as glioblastoma. Glioblastomas typically have a lot of things wrong with them, meaning most of our inherent hard-wired cellular defense mechanisms have been overridden. Even worse, glioblastomas tend to harbor a subset of cells known as […]

  11. August 9, 2014

    […] The Hallmarks of Cancer focus on 10 underlying principles shared by all cancers. The seventh Hallmark is defined as genome instability and mutation. […]

  12. August 9, 2014

    […] The Hallmarks of Cancer focus on 10 underlying principles shared by all cancers. The Sixth Hallmark of Cancer is defined as “Tissue Invasion and Metastasis.” […]

  13. August 9, 2014

    […] Read more Hallmarks of Cancer […]

  14. August 9, 2014

    […] Read more Hallmarks of Cancer […]

  15. October 14, 2014

    […] The Hallmarks of Cancer are ten underlying principles shared by all cancers. The ninth Hallmark of Cancer is defined as “Reprogramming Energy Metabolism”. […]

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