Photochemical responses of three marine phytoplankton species exposed to ultraviolet radiation and increased temperature: Role of photoprotective mechanisms

Uveal melanoma (UM) is currently classified by the World Health Organisation as a melanoma caused by risk factors other than cumulative solar damage. However, factors relating to ultraviolet radiation (UVR) susceptibility such as light-coloured skin and eyes, propensity to burn, and proximity to the equator, frequently correlate with higher risk of UM. These risk factors echo those of the far more common cutaneous melanoma (CM), which is widely accepted to be caused by excessive UVR exposure, suggesting a role of UVR in the development and progression of a proportion of UM. Indeed, this could mean that countries, such as Australia, with high UVR exposure and the highest incidences of CM would represent a similarly high incidence of UM if UVR exposure is truly involved. Most cases of UM lack the typical genetic mutations that are related to UVR damage, although recent evidence in a small minority of cases has shown otherwise. This review therefore reassesses statistical, environmental, anatomical, and physiological evidence for and against the role of UVR in the aetiology of UM.

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Phenylhydrazone and Quinazoline Derivatives from the Cold-Seep-Derived Fungus Penicillium oxalicum

Marine Drugs ◽

10.3390/md19010009 ◽

2020 ◽

Vol 19 (1) ◽

pp. 9

Author(s):

Ya-Ping Liu ◽

Sheng-Tao Fang ◽

Zhen-Zhen Shi ◽

Bin-Gui Wang ◽

Xiao-Nian Li ◽

...

Keyword(s):

Deep Sea ◽

Spectroscopic Data ◽

2D Nmr ◽

Penicillium Oxalicum ◽

Marine Phytoplankton ◽

Cold Seep ◽

Phytoplankton Species ◽

X Ray ◽

X Ray Crystallography ◽

Quinazoline Derivatives

Three new phenylhydrazones, penoxahydrazones A–C (compounds 1–3), and two new quinazolines, penoxazolones A (compound 4) and B (compound 5), with unique linkages were isolated from the fungus Penicillium oxalicum obtained from the deep sea cold seep. Their structures and relative configurations were assigned by analysis of 1D/2D NMR and mass spectroscopic data, and the absolute configurations of 1, 4, and 5 were established on the basis of X-ray crystallography or ECD calculations. Compound 1 represents the first natural phenylhydrazone-bearing steroid, while compounds 2 and 3 are rarely occurring phenylhydrazone tautomers. Compounds 4 and 5 are enantiomers that feature quinazoline and cinnamic acid units. Some isolates exhibited inhibition of several marine phytoplankton species and marine-derived bacteria.

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STUDIES OF CARBON AND NITROGEN METABOLISM BY THREE MARINE PHYTOPLANKTON SPECIES IN NITRATE-LIMITED CONTINUOUS CULTURE1 ,2

Journal of Phycology ◽

10.1111/j.1529-8817.1978.tb02460.x ◽

1978 ◽

Vol 14 (4) ◽

pp. 406-416 ◽

Cited By ~ 82

Author(s):

Edward A. Laws ◽

Diana C. L. Wong

Keyword(s):

Nitrogen Metabolism ◽

Marine Phytoplankton ◽

Phytoplankton Species ◽

Carbon And Nitrogen ◽

Carbon And Nitrogen Metabolism

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Ultraviolet Radiation and Chronic Inflammation—Molecules and Mechanisms Involved in Skin Carcinogenesis: A Narrative Review

Life ◽

10.3390/life11040326 ◽

2021 ◽

Vol 11 (4) ◽

pp. 326

Author(s):

Magdalena Ciążyńska ◽

Irmina Olejniczak-Staruch ◽

Dorota Sobolewska-Sztychny ◽

Joanna Narbutt ◽

Małgorzata Skibińska ◽

...

Keyword(s):

Ultraviolet Radiation ◽

Chronic Inflammation ◽

Potential Role ◽

Tumor Formation ◽

Skin Carcinogenesis ◽

Molecular Networks ◽

Cancer Therapies ◽

Inflammatory Microenvironment ◽

Skin Cancers

The process of skin carcinogenesis is still not fully understood. Both experimental and epidemiological evidence indicate that chronic inflammation is one of the hallmarks of microenvironmental-agent-mediated skin cancers and contributes to its development. Maintaining an inflammatory microenvironment is a condition leading to tumor formation. Multiple studies focus on the molecular pathways activating tumorigenesis by inflammation and indicate several biomarkers and factors that can improve diagnostic and prognostic processes in oncology and dermatology. Reactive oxygen species produced by ultraviolet radiation, oxidizers, or metabolic processes can damage cells and initiate pro-inflammatory cascades. Considering the potential role of inflammation in cancer development and metastasis, the identification of early mechanisms involved in carcinogenesis is crucial for clinical practice and scientific research. Moreover, it could lead to the progress of advanced skin cancer therapies. We focus on a comprehensive analysis of available evidence and on understanding how chronic inflammation and ultraviolet radiation can result in skin carcinogenesis. We present the inflammatory environment as complex molecular networks triggering tumorigenesis and constituting therapeutic targets.

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