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In a paper this week in Science, Vogelstein and Cristian Tomasetti, who joined the biostatistics department at Hopkins in 2013, put forth a mathematical formula to explain the genesis of cancer. Here's how it works: Take the number of cells in an organ, identify what percentage of them are long-lived stem cells, and determine how many times the stem cells divide. With every division, there's a risk of a cancer-causing mutation in a daughter cell. Thus, Tomasetti and Vogelstein reasoned, the tissues that host the greatest number of stem cell divisions are those most vulnerable to cancer. When Tomasetti crunched the numbers and compared them with actual cancer statistics, he concluded that this theory explained two-thirds of all cancers.

This case study presents a realistic example of drinking water contamination within a fictional local community and leads students through an abbreviated human health risk assessment. Students are provided background information about the extent of the contamination and a description of the contaminated site and are then required to calculate both the cancer and non-cancer risks to the community. This exercise is appropriate for an environmental toxicology or environmental risk assessment course. It works well after a lecture on the basics of risk assessment including how to calculate exposure intakes and risk estimates.

This directed case study follows the story of "Pauline," a 20-year-old college student who has just received results from a personal genetic testing kit she purchased online. The report shows a negative result for variants of the BRCA 1 and 2 genes, which are associated with a greater risk for breast cancer. Although Pauline has a family history of breast cancer, she concludes that she no longer needs to be concerned, or does she? As students work through the questions in this case study, they review the role of genes and how they code for proteins as well as the effects of proteins on health, especially on cellular growth regulation and cancer. They also learn about the process of genetic testing and consider the ramifications of positive and negative tests for diseases or health conditions, especially with respect to breast cancer. The case is designed for non-science majors in a scientific methods course and could also be used in an introductory biology course. The questions in the case could be adapted for an upper level genetics class.

NCI Fact Sheet on cell phone and cancer

Penn Medicine Cancer resources for patients and healthcare professionals

Welcome to Your Disease Risk, the source on prevention. Here, you can find out your risk of developing five of the most important diseases in the United States and get personalized tips for preventing them. Developed over the past ten years by world-renowned experts, Your Disease Risk collects the latest scientific evidence on disease risk factors into one easy-to-use tool.

Researchers from the World Health Organization's International Agency for Research on Cancer (IARC) looked at more than 1,000 epidemiological studies and found that "excess body fatness" is also linked to the risk of developing gastric, liver, gallbladder, pancreatic, ovarian, thyroid, blood (multiple myeloma) and brain (meningioma) cancers.

A worldwide study of the DNA of 100,000 women has discovered two new genetic variants associated with an increased risk of breast cancer. The genetic variants are specifically linked to the most common form of breast cancer, oestrogen receptor positive, and provide important insights into how the disease develops.

This video excerpt from NOVA examines the dilemma some people face when they are deciding whether to undergo genetic testing. Journalist Catherine Elton describes her decision to refuse a test for BRCA1, a mutation that signals an increased risk of breast and ovarian cancers, despite the history of disease in her family. The video also explains that genetic testing results can help some individuals improve their wellness, prevent the onset of diseases they are at risk for, or lessen the harmfulness of diseases they do contract.

Cancer defined with risk factors and treatments

A local delicacy in north-east Thailand, made from raw fish, has been found to be behind a high incidence of liver cancer in the area, and doctors are trying to educate people about the risk.

The researchers' approach to developing the method was adopted from food science, where it is used for control of complex industrial processes. Basically, it involves handling and analysing huge amounts of biological data in a holistic and explorative way. The researchers analysed all compounds a blood sample contains instead of - as is often done in health and medical science - examining what a single biomarker means in relation to a specific disease. "When a huge amount of relevant measurements from many individuals is used to assess health risks - here breast cancer - it creates very high quality information. The more measurements our analyses contain, the better the model handles complex problems," continued Professor Rasmus Bro.

Stress is implicated in increased tumor progression risk and poor survival in cancer patients. A number of recent studies have linked these effects to the promotion of tumor cell dissemination through the bloodstream via stress-induced pathways. Now, a mouse study led by researchers in Australia has revealed the mechanisms by which stress modulates cancer's spread through another transport network open to tumor cells-the lymphatic system.

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The woman in this case had cachexia, a metabolic disorder that affects some 9 million people worldwide, including as many as 80% of people with advanced cancer. It typically involves extreme weight- and muscle-loss, makes routine activities difficult and increases the risk of deadly complications such as infections. Adding calories doesn't reverse cachexia, and McClement says that the disorder sometimes provokes extreme reactions from family members because it serves as visual confirmation of their worst fears. "It's a constant reminder that the person is sick and is not going to get better," says McClement.

CRISPR still has a long way to go before it can be used safely and effectively to repair-not just disrupt-genes in people. That is particularly true for most diseases, such as muscular dystrophy and cystic fibrosis, which require correcting genes in a living person because if the cells were first removed and repaired then put back, too few would survive. And the need to treat cells inside the body means gene editing faces many of the same delivery challenges as gene transfer-researchers must devise efficient ways to get a working CRISPR into specific tissues in a person, for example. CRISPR also poses its own safety risks. Most often mentioned is that the Cas9 enzyme that CRISPR uses to cleave DNA at a specific location could also make cuts where it's not intended to, potentially causing cancer.