The Big "C": What's the latest?

We often think of cancer as a new disease, or at least one that has surfaced since the Industrial Revolution. But researchers found the 3,200-year-old skeletal remains of a young man found in a tomb in Africa harbor the oldest evidence yet of cancer in humans.(1) The bones had significant pockmarks of metastatic cancer. The researchers speculated as to the cause of his cancer.

Because smoky fires contain just as many unhealthy chemicals as cigarette smoke, they think he might have inhaled smoke from wood-burning fires. Alternatively, he may have been exposed to the parasite schistosomiasis, which is linked to bladder and breast cancer in the same geographical region today. It’s also possible the 25- to 35-year-old man may have had a genetic predisposition to cancer.(1)

There has been some dialogue about diagnostic dental radiographs causing brain cancer. A 2013 study evaluated the risk of benign brain tumors (BBTs) and malignant brain tumors (MBTs) associated with dental diagnostic X-rays, by means of a large population-based case–control study.(2) The results of the study indicated that the risk of BBT increases as the frequency of received dental diagnostic X-ray increases. No significant association was found between MBTs and dental diagnostic X-ray exposure. The authors concluded that exposure to dental diagnostic X-rays in oral and maxillofacial care increases the risk of BBTs, but not MBTs. This is consistent with earlier findings about the relationship between dental diagnostic X-rays intracranial meningioma.(3) Women were found to be at higher risk than men, and individuals between ages 20 and 60 comprise most patients.(2) As always, the study did have some limitations. Recently, a mother that gave birth to twins was diagnosed with a rare placental cancer. Choriocarcinoma is a malignant form of gestational trophoblastic disease (GTD), tumors that involve abnormal growth of cells inside a woman’s uterus.(4) This particular type affects only about 2 to 7 of every 100,000 pregnancies in the United States.(4) Choriocarcinoma is much more likely than other types of GTD to grow quickly and spread to organs away from the uterus. About one-quarter of women who develop this disease miscarry. Risk factors for gestational trophoblastic disease are: age; prior molar pregnancy (a molar pregnancy is an abnormality of the placenta, caused by a problem when the egg and sperm join together at fertilization); prior miscarriages; blood type A or AB; taking birth control pills; and family history.(4) Some good news. Cornell researchers discovered direct genetic evidence that a family of genes, called MicroRNA-34 (miR-34), are genuine tumor suppressors. Future work of this group and others will continue to scrutinize the role of p53/miR-34/MET genes in stem cell growth and cancer. The findings have positive implications for many types of cancer.(5)

Also relating to prostate cancer, Cancer Research UK-funded scientists have developed a new way to test the effectiveness of a drug for prostate cancer that has spread to the bone, which is currently incurable.(6) They successfully used a combination of imaging techniques to see how a drug called cabozantinib can stop this type of prostate cancer growing in mice. The imaging method involves a combination of bioluminescent cells, magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT) and computed tomography (CT). This combination of techniques allows for the most accurate clarity on tumor growth within bone to date, as well as analysis of the impact on the healthiness of the bones themselves. More good news!

Researchers have identified a protein that causes cells to release from adjacent cells and migrate away from healthy mammary, or breast, tissue in mice.(7) They also found that deletion of a cellular "Velcro protein" does not cause the single-celled migration expected. Their results could help clarify the molecular changes required for cancer cells to metastasize. Because epithelial cells give rise to 85 percent of all cancers, the work may have implications outside of breast cancer.(7)

And lastly, what is the link between sleeping pills and cancer? Three percent of nearly 1,000 people questioned said they had used prescription sleep aids during the previous month, according to the 1999-2010 National Health and Education Survey (NHANES).(8)

A 2012 study reported that eight of the most commonly used sleep aids, including zolpidem and temazepam, were associated with an increased risk of cancer and death.(9) Rates of cancer were 35 percent higher in people who took at least 132 sleeping pills per year compared to people who didn’t use them. People who took 18 to 132 pills were more than four times as likely to die. These people had a risk of death 3.6 times higher than people who didn’t use sleep aids.

Bottom line: Only take medications if you must, for as short a time as possible!

References 1. Binder M, Roberts C, Spencer N, Antoine D, and Cartwright C. On the Antiquity of Cancer: Evidence for Metastatic Carcinoma in a Young Man from Ancient Nubia (c. 1200BC). PLoS ONE 9(3): e90924. doi:10.1371/journal.pone.0090924. 2. Lin MC, Lee CF, Lin CL, Wu YC, Wang HE, Chen CL, Sung FC, and Kao CH. Dental diagnostic X-ray exposure and risk of benign and malignant brain tumors. Annals of Oncology 00: 1–5, 2013. doi:10.1093/annonc/mdt016. 3. Longstreth WT, Jr, Phillips LE, Drangsholt M et al. Dental X-rays and the risk of intracranial meningioma: a population-based case-control study. Cancer 2004; 100: 1026–1034. 4. http://www.cancer.org/cancer/gestationaltrophoblasticdisease/detailedguide/gestational-trophoblastic-disease-what-is-g-t-d. 5. Cheng et al. miR-34 Cooperates with p53 in Suppression of Prostate Cancer by Joint Regulation of Stem Cell Compartment, Cell Reports (2014), http://dx.doi.org/10.1016/j.celrep.2014.02.023. http://download.cell.com/cell-reports/pdf/PIIS2211124714001235.pdf?intermediate=true. 6. Graham, T.J. et al. Pre-clinical Evaluation of Imaging Biomarkers for Prostate Cancer Bone Metastasis and Response to Cabozantinib. Journal of the National Cancer Institute (2014). 7. Shamir ER, Pappalardo E, Jorgens DM, et al. Twist1-induced dissemination preserves epithelial identity and requires E-cadherin. J Cell Biol 2014 204:839-856. Published March 3, 2014, doi:10.1083/jcb.201306088. 8. Bertisch SM; Herzig SJ; Winkelman JW; Buettner C. National use of prescription medications for insomnia: NHANES 1999-2010. SLEEP 2014;37(2):343-349. 9. Kripke DF, Langer RD, Kline LE. Hypnotics’ association with mortality or cancer: a matched cohort study. BMJ Open 2012;2: e000850. doi: 10.1136/ bmjopen-2012-000850.