Novel UV-B Phototherapy With a Light-Emitting Diode Device Prevents Atherosclerosis by Augmenting Regulatory T-Cell Responses in Mice

BACKGROUND

Ultraviolet B (UV-B) irradiation is an effective treatment for human cutaneous disorders and was shown to reduce experimental atherosclerosis by attenuating immunoinflammatory responses. The aim of this study was to clarify the effect of specific wavelengths of UV-B on atherosclerosis and the underlying mechanisms focusing on immunoinflammatory responses.

METHODS AND RESULTS

Based on light-emitting diode technology, we developed novel devices that can emit 282 nm UV-B, which we do not receive from natural sunlight, 301 nm UV-B, and clinically available 312 nm UV-B. We irradiated 6-week-old male atherosclerosis-prone Apoe-/- (apolipoprotein E-deficient) mice with specific wavelengths of UV-B and evaluated atherosclerosis and immunoinflammatory responses by performing histological analysis, flow cytometry, biochemical assays, and liquid chromatography/mass spectrometry-based lipidomics. Irradiation of 282 nm UV-B but not 301 or 312 nm UV-B significantly reduced the development of aortic root atherosclerotic plaques and plaque inflammation. This atheroprotection was associated with specifically augmented immune responses of anti-inflammatory CD4+ Foxp3 (forkhead box P3)+ regulatory T cells in lymphoid tissues, whereas responses of other immune cells were not substantially affected. Analysis of various lipid mediators revealed that 282 nm UV-B markedly increased the ratio of proresolving to proinflammatory lipid mediators in the skin.

CONCLUSIONS

We demonstrated that 282 nm UV-B irradiation effectively reduces aortic inflammation and the development of atherosclerosis by systemically augmenting regulatory T-cell responses and modulating the balance between proresolving and proinflammatory lipid mediators in the skin. Our findings indicate that a novel 282 nm UV-B phototherapy could be an attractive approach to treat atherosclerosis.

Clinicopathological significance of MYL9 expression in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma is one of the most aggressive malignancies, and often involves invasion and distant metastasis from the early tumor stages. Myosin II reportedly plays a key role in regulating tumor progression and metastasis.

AIMS

We examined whether myosin regulatory light polypeptide 9 (MYL9) regulates cancer cell proliferation.

METHODS AND RESULTS

To investigate the expression pattern and clinical significance of MYL9 in pancreatic ductal adenocarcinoma, we performed immunohistochemical analysis of samples collected from 101 patients with pancreatic ductal adenocarcinoma. The expression of MYL9 was investigated to evaluate its functional role and contribution to proliferation and apoptosis in pancreatic ductal adenocarcinoma cells in vitro. The results showed that MYL9 was predominantly expressed in the cytoplasm and membrane of pancreatic ductal adenocarcinoma cells. Multivariate analysis indicated that MYL9 acted as an independent prognostic factor for overall survival and distant metastasis-free survival. MYL9 expression was strongly associated with malignancy in in vitro analyses, including proliferation and anti-apoptotic activities.

CONCLUSIONS

Our findings suggest that MYL9 is an independent prognostic factor of pancreatic ductal adenocarcinoma. MYL9 is a crucial biomarker and potential therapeutic target for pancreatic ductal adenocarcinoma.

Cancer metabolism challenges genomic instability and clonal evolution as therapeutic targets

Although cancer precision medicine has improved diagnosis and therapy, refractory cancers such as pancreatic cancer remain to be challenging targets. Clinical sequencing has identified the significant alterations in driver genes and traced their clonal evolutions. Recent studies indicated that the tumor microenvironment elicits alterations in cancer metabolism, although its involvement in the cause and development of genomic alterations has not been established. Genomic abnormalities can contribute to the survival of selected subpopulations, recently recognized as clonal evolution, and dysfunction can lead to DNA mutations. Here, we present the most recent studies on the mechanisms of cancer metabolism involved in the maintenance of genomic stability to update current understanding of such processes. Sirtuins, which are NAD+-dependent protein deacetylases, appear to be involved in the control of genomic stability. Alterations of deleterious subpopulations would be exposed to selective pressure for cell survival. Recent studies indicated that a new type of cell death, ferroptosis, determines the survival of clones and exert cancer-restricting or -promoting effects to surrounding cells in the tumor microenvironment. Suppressing genomic instability and eliminating deleterious clones by cell death will contribute to the improvement of cancer medicine. Furthermore, the elucidation of the mechanisms involved is seen as a bridgehead to the pharmacologic suppression of such refractory cancers as pancreatic cancer.