University of Southern Denmark

FRIDAY, March 7, 2025 -- Tattooed individuals have an increased risk for lymphoma and skin cancers, according to a study recently published in BMC Public Health . Signe Bedsted Clemmensen, from the University of Southern Denmark in Odense, and colleagues conducted two designs of twin studies to examine the potential association between tattoo ink exposure and development of certain types of cancers: a cohort study including 2,367 randomly selected twins and a case-control study involving 316 twins born from 1960 to 1996. The researchers found that the risk for skin cancer (any type except basal cell carcinoma) was 1.62 times higher among tattooed individuals in the case-control study (95 percent confidence interval, 1.08 to 2.41). The hazard ratio was 1.33 (95 percent confidence interval, 0.46 to 3.84) for a twin-matched analysis of 14 twin pairs discordant for tattoo ink exposure and skin cancer. Increased hazards were found for tattoos larger than the palm of a hand for skin cancer and lymphoma (hazard ratios [95 percent confidence intervals], 2.37 [1.11 to 5.06] and 2.73 [1.33 to 5.60], respectively). An individual-level analysis resulted in hazard ratios of 3.91 (95 percent confidence interval, 1.42 to 10.8) and 2.83 (95 percent confidence interval, 1.30 to 6.16) for skin cancer and basal cell carcinoma, respectively, in the cohort study design. "We are concerned that tattoo ink has severe public health consequences since tattooing is abundant among the younger generation," the authors write. "Studies that pinpoint the etiological pathway of tattoo ink-induced carcinogenesis are recommended." Abstract/Full Text Whatever your topic of interest, subscribe to our newsletters to get the best of Drugs.com in your inbox.

THURSDAY, March 6, 2025 -- People put a lot of thought into getting a tattoo – the design they desire, the location they prefer and the message their body art will send to others. Most don’t think about the impact their tattoo might have on their long-term health, but perhaps they should, a new study suggests. Tattoos appear to increase a person’s risk of skin cancer between 33% and 62%, according to a new Danish study in the journal BMC Health . Results also indicate there's increased cancer risk from larger tattoos. Tattoos larger than the palm of a hand more than double a person’s risk of skin cancer and nearly triple their risk of lymphoma , or cancer of the lymph nodes, researchers found. When tattoo ink is injected into the skin, ink particles can migrate to and accumulate inside the lymph nodes, researchers said. “We can see that ink particles accumulate in the lymph nodes, and we suspect that the body perceives them as foreign substances,” researcher Henrik Frederiksen , a clinical professor at the University of Southern Denmark, said in a news release. “This may mean that the immune system is constantly trying to respond to the ink, and we do not yet know whether this persistent strain could weaken the function of the lymph nodes or have other health consequences,” he added. About 32% of Americans have a tattoo, and 22% have more than one, according to a 2023 poll conducted by the Pew Research Center. For this study, researchers analyzed data from an ongoing study of Danish twins. They compared nearly 2,400 randomly selected twins born between 1960 and 1996, as well as 316 twins where one twin had been diagnosed with cancer. “The unique aspect of our approach is that we can compare twin pairs where one has cancer, but they otherwise share many genetic and environmental factors,” senior researcher Jacob von Bornemann Hjelmborg , a professor of biostatistics at the University of Southern Denmark, said in a news release. By comparing tattoo patterns alongside cancer diagnoses, researchers found that people with tattoos have a higher occurrence of both skin cancer and lymphoma. The analysis showed that tattoos larger than the palm of a hand increased skin cancer risk by nearly 2.4-fold, and lymphoma by 2.8-fold. This rate accounts for a person’s age, when they got their tattoo, and how long they’d been followed in the study. “This suggests that the bigger the tattoo and the longer it has been there, the more ink accumulates in the lymph nodes,” lead researcher Signe Bedsted Clemmensen , an assistant professor of biostatistics at the University of Southern Denmark, said in a news release. Previous research has suggested that certain pigments in tattoo ink might be less healthy than others, but this study found no clear link between cancer and specific ink colors, researchers said. “We know from other studies that ink can contain potentially harmful substances, and for example, red ink more often causes allergic reactions. This is an area we would like to explore further,” Clemmensen said. Researchers next plan to focus on how ink particles affect the lymph nodes, and whether certain types of lymphoma have a stronger link to tattoos than others. “We want to gain a better understanding of the biological mechanisms — what happens in the lymph nodes when they are exposed to ink particles over decades? This can help us assess whether there is a real health risk and what we might do to reduce it,” Clemmensen concluded. Whatever your topic of interest, subscribe to our newsletters to get the best of Drugs.com in your inbox.

Bacteria are experts at evolving resistance to antibiotics. One resistance strategy is to cover their cell walls in sticky and gooey biofilm that antibiotics cannot penetrate. A new discovery could put a stop to this strategy. Antibiotic resistant bacteria are experts in evolving new strategies to avoid being killed by antibiotics. One such bacterium is Pseudomonas aeruginosa, which is naturally found in soil and water, but also hospitals, nursing homes and similar institutions for persons with weakened immune systems are home for strains of this bacterium. As many P. Aeruginosa strains found in hospitals are resistant to most antibiotics in use, science is forced to constantly search for new ways to kill them. Now, at team of researchers from Department of Biochemistry and Molecular Biology and Department of Clinical Microbiology, University of Southern Denmark, have discovered a weakness in P. Aeruginosa with the potential to become the target for a new way to attack it. The team has published their findings in the journal Microbiology Spectrum. The authors are Clare Kirkpatrick, Magnus Z. Østergaard, Flemming D. Nielsen and Mette H. Meinfeldt. Thick and slimy biofilm The team discovered a mechanism, that reduces the formation of biofilm on the surface of P. Aeruginosa. The formation of sticky, slimy biofilm is a powerful tool used by bacteria to protect themselves against antibiotics -- a trick also used by P. Aeruginosa. "This biofilm can be so thick and gooey that antibiotic cannot penetrate the cell surface and reach its target inside the cell," said Clare Kirkpatrick, head of research at Department of Biochemistry and Molecular Biology, adding: "Maybe one day, we could pharmacologically stimulate this mechanism to reduce biofilm development on the surface of P. Aeruginosa." Three new genes Specifically, the researchers worked with three newly discovered genes in a lab-grown strain of P. Aeruginosa. When they overexpressed these genes, they saw a strong reduction of biofilm. Of significance is that the system affected by the genes is part of the P. Aeruginosa core genome, meaning that it is universally found in all the P. Aeruginosa strains sequenced so far. "Being part of P. Aeruginosa's core genome, this system has been found in all investigated strains of P. Aeruginosa, including a large variety of strains isolated from patients. So, there is reason to believe that reduction of biofilm via this system should be effective in all known strains of P. Aeruginosa", said Clare Kirkpatrick. Bacteria strains can evolve individually and mutate quickly and constantly when they are under pressure. It is not uncommon for patients infected with a P. Aeruginosa strain to initially respond well to antibiotic treatment but then become resistant as the strain evolves resistance during treatment. Strains mutate, but their common core genome does not change. Stressing the cell wall In their experiments, the researchers activated the biofilm reducing system by overexpressing genes. But they also discovered that the system is naturally stimulated by cell wall stress. "So, if we stress the cell wall, it may naturally lead to a reduction in biofilm, making it easier for antibiotic to penetrate the cell wall," said Clare Kirkpatrick, adding: "Currently, cell wall-targeted drugs are not widely used against P. Aeruginosa, but perhaps, they could start to be used as additives to help reduce biofilm production and improve access of the existing antibiotics to the cells." Bacteria cell wall is very different from human cell wall When combating infectious bacteria, there are only a limited number of targets to attack. Targets found in both bacterial and human cells cannot be attacked, as the antibiotics would also affect human cells. Bacterial cells and human cells have some targets in common, such as the process that replicates DNA and the processes controlling basic glucose metabolism or respiration in cells. Among the targets unique to bacteria are various protein functions and also the bacterial cell wall is considered a suitable target, as it is very different from the human cell wall.