Reasons for Cancer Spread Found in Protein

An article released yesterday by Reuters News Service and found in the Journal of Nature indicated that Austrian and Canadian researchers have identified and blocked a protein called RANKL, which is linked to cancer spread. The protein is found in bone marrow cells and was found to be a chief cause for cancer spread in mice because it sends signals attracting tumor cells to the bones. Cancer that has spread beyond its original area, which is called metastasis, is more difficult to treat. Metastasis causes a great deal of pain in cancer victims.

This finding explains why cancer cells can spread to bones and suggests that interfering with this process may stop the spread. Mice treated with a drug to block RANKL had fewer tumors in their bones than the untreated control group. However, the drug was not successful at stopping the spread of cancer to other places in the body. This finding relates to breast cancer cells, which often contain receptors for RANKL. The drug may improve the quality of life in patients if metastasis can be stopped. Researchers stress that these findings need further examination because the drug was tested only on mice.

The article suggested that there may be other proteins that are possibly involved in the spread of tumors, since RANKL only seems to be associated with cancer spread to the bones. It will be interesting to see if any other proteins, with further research, are identified that cause cancer to spread to other parts of the body. Perhaps then, like this experiment, drugs can be found to prevent their spread, making it easier to treat patients with different types of cancer. More information about RANKL, including its function and its signaling pathway can be found here.

Spring Break at Wal-Mart

A Drake University sophomore spent 41 consecutive hours at Wal-Mart to do background research for a writing article. Click on the link to find out more.

Bacon That's Good for You?

An article released Sunday by Reuters News Service said that U.S. scientists have genetically engineered pigs to produce beneficial fatty acids that could make foods like bacon much healthier. Researchers transferred a worm gene called fat-1 into pig cells and used cloning technology to create embryonic cells that were implanted into the womb of a normal pig. The gene allowed the pigs to produce an enzyme that converted omega-6 fatty acids (which the pigs naturally produce) into omega-3 fatty acids. Omega-3 fatty acids improve cardiac function, reduce the risk of heart disease and are necessary for proper fetal development in women. Omega-3s are only found in dietary supplements and certain types of fish, but some of these fish contain high levels of mercury. Omega-6 fatty acids are one of the reasons for high rates of obesity and heart disease. As of now, it is not known whether these genetically engineered pigs will ever be made available for human consumption. Researchers will conduct further tests on the effects of the additional omega-3s in the pigs. Experiments are also being conducted to try and make fish, chickens, and cows with extra omega-3s.

It will be interesting to see if these pigs actually become something humans consume on a regular basis. The article briefly touches in the ethical dilemma involved with genetic research like this. Consumers may avoid food like this out of fear of its unnatural properties. Whether these pigs will be specially labeled for their special qualities has not been determined. Most consumers eat genetically engineered fruits and vegetables, many of which are not labeled, without a problem.

More information on omega-3 fatty acids from the American Heart Association can be found here.

Grapefruit Juice Increases Drug Potency

A recent article from the New York Times (free subscription required for viewing), detailed how grapefruit juice can increase the potency of some drugs to potentially dangerous levels through its inhibition of certain enzymes.

A group of enzymes called the cytochrome P 450 system, specifically an enzyme called CYP 3A4, held the answer as to why grapefruit juice increased the power of certain drugs so greatly. These enzymes break down many drugs and toxins into substances that are "less potent or more easily excreted or both," according to the article. Grapefruit juice inhibits the ability of CYP 3A4 to break down these drugs, increasing its potency because more can enter the bloodstream. The drug specifically binds with the enzyme in the intestines, so this effect can only happen if the drug is taken orally.

The vast majority of grapefruit juice’s interactions with drugs are not very serious, though some special cases do arise. Cholesterol lowering drugs like Lipitor and Zocor have increased potency, which can lead to a fatal muscle disorder. Grapefruit juice can also hinder the metabolism of drugs like Prozac, used to treat depression. Grapefruit juice has the greatest effect, but lime juice and orange juice made from Seville oranges affect the enzyme in similar ways.

Solution: take the drugs with water.

The X Advantage

Genetic research into differences between the sexes is increasingly showing that the extra X chromosome in women helps them fight off disease and may be the reason for their increased lifespan. Men are born with one X chromosome and a much smaller and relatively "weak" Y chromosome, which is involved in the development of male characteristics. Women are born with two X chromosomes.

In the United States, according to 2003 U.S. Census data, women live an average of 80.1 years, while men only live an average of 74.8 years. More males die of chromosomal defects than females do.

The X chromosome has about 1,100 genes on it that are involved in blood clotting, muscle function, and ridding cells of waste, among other things. It may also be the reason why girls comprehend colors differently, develop different personality traits and acquire longer attention spans. If a defect or mutation occurs on the X chromosome in a male, he is stuck with the defect whereas females have a back-up copy of the chromosome. Females can be considered "mosaics," since in a given cell only one of the X chromosomes can be expressed. Cells can express either the father's X chromosome genes or the mother's X chromosome genes in a cell, which leads to more variety overall.

Though the article does not mention it, it probably is incorrect to assume that the X chromosome is the only reason females, on average, live longer than men. There are many factors contributing to longevity, including nutrition, environment, occupation, and lifestyle, to name a few. But the article provides compelling evidence to suggest that the double X chromosome is at least part of the reason.

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