Many of us hear how cholesterol can be bad for us. The heart disease causing effects are already well known, but how does cholesterol contribute to cancer development?
Cholesterol has many roles in our body, and there are different types. According to Harvard Medical School's Health Publishing webpage, Cholesterol is broken down to these types:
Cholesterol makes up over 90% of the plasma membranes of our cells. Cholesterol effects different receptors, enzymes, and ion channels. For this topic, we will focus on TRPM7 receptors.
TRPM7 is an ion channel that maintains flow of magnesium and calcium into a cell. An over-expression of TRPM7 contributes to the metastasis and proliferation of several cancers including: breast, pancreatic, gastric, and nasopharyngeal cancers.
Statins have been found to reduce the incidence of prostate cancer by inhibiting cholesterol-induced TRPM7 activation.
When cholesterol interacts with TRPM7 channels, the pore dilates allowing a flood of calcium ions into a cell. Calcium regulates kinases that are involved in proliferation, migration, invasion, motility, gene transcription and apoptosis. Too much calcium entering the cell will mutate the cell, and can alter it into an invasive cancer.
Eating animal products are packed full of cholesterol, and will increase levels of LDL cholesterol. Statins are designed to reduce LDL cholesterol. Different statins will change the current in TRPM7 channels, such as mevastatin decreased TRPM7 currents more than simvastatin. Does it make sense to have to take pills just to be able to keep eating animals and dairy?
Fun Fact: Cigarette smoking increases cholesterol!
Going vegan is the easiest way to lower cholesterol levels. Some specific foods/nutrients that can help with cholesterol are:
We do need at least 25-30 grams of fiber per day to help lower cholesterol. Low fiber diets backs things up in our intestines, and increases the absorption of cholesterol. Stanols also help stop the absorption of cholesterol. Sterols and stanols are found in whole grains, legumes, fruit, nuts. and seeds.
Sun, Y., Sukumaran, P., Varma, A., Derry, S., Sahmoun, A. E., & Singh, B. B. (2014). Cholesterol-induced activation of TRPM7 regulates cell proliferation, migration, and viability of human prostate cells. Biochimica et biophysica acta, 1843(9), 1839–1850. doi:10.1016/j.bbamcr.2014.04.019
Sun Y, Selvaraj S, Varma A, Derry S, Sahmoun AE, Singh BB. Increase in serum Ca2+/Mg2+ ratio promotes proliferation of prostate cancer cells by activating TRPM7 channels. J Biol Chem. 2013 Jan 4;288(1):255-63. doi: 10.1074/jbc.M112.393918.
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Goluszko, P., & Nowicki, B. (2005). Membrane cholesterol: a crucial molecule affecting interactions of microbial pathogens with mammalian cells. Infection and immunity, 73(12), 7791–7796. doi:10.1128/IAI.73.12.7791-7796.2005
Corliss, Julie. How it’s made: Cholesterol production in your body. Harvard Health Publishing. February, 2017 https://www.health.harvard.edu/heart-health/how-its-made-cholesterol-production-in-your-body
Website no author. Harvard Health Publishing. https://www.health.harvard.edu/heart-health/11-foods-that-lower-cholesterol
Website no author. https://www.webmd.com/cholesterol-management/guide/hdl-cholesterol-the-good-cholesterol#1