Different toxic effects of YTX in tumor K-562 and lymphoblastoid cell lines

Current Trends and New Challenges in Marine Phycotoxins

Marine phycotoxins are a multiplicity of bioactive compounds which are produced by microalgae and bioaccumulate in the marine food web. Phycotoxins affect the ecosystem, pose a threat to human health, and have important economic effects on aquaculture and tourism worldwide. However, human health and food safety have been the primary concerns when considering the impacts of phycotoxins. Phycotoxins toxicity information, often used to set regulatory limits for these toxins in shellfish, lacks traceability of toxicity values highlighting the need for predefined toxicological criteria. Toxicity data together with adequate detection methods for monitoring procedures are crucial to protect human health. However, despite technological advances, there are still methodological uncertainties and high demand for universal phycotoxin detectors. This review focuses on these topics, including uncertainties of climate change, providing an overview of the current information as well as future perspectives.

MTMR3 is upregulated in patients with breast cancer and regulates proliferation, cell cycle progression and autophagy in breast cancer cells

As a member of the myotubularin family, myotubularin related protein 3 (MTMR3) has been demonstrated to participate in tumor development, including oral and colon cancer. However, little is known about its functional roles in breast cancer. In the present study, the expression of MTMR3 in breast cancer was evaluated by immunohistochemical staining of tumor tissues from 172 patients. Online data was then used for survival analysis from the PROGgeneV2 database. In vitro, MTMR3 expression was silenced in MDA-MB-231 cells via lentiviral shRNA transduction. MTT, colony formation and flow cytometry assays were performed in the control and MTMR3-silenced cells to evaluate the cell growth, proliferation and cell cycle phase distribution, respectively. Western blotting was used to evaluate the protein expression levels of autophagy-related markers. The results demonstrated that the expression of MTMR3 in breast cancer tissues was significantly increased compared with adjacent normal tissues. MTMR3 was highly expressed in triple-negative breast cancer and was associated with disease recurrence. MTMR3 knockdown in MDA-MB-231 cells inhibited cell proliferation and induced cell cycle arrest and autophagy. The present results indicated that MTMR3 may have an important role in promoting the progression of breast cancer, and its inhibition may serve as a promising therapeutic target for breast cancer treatment.

Yessotoxin, a Marine Toxin, Exhibits Anti-Allergic and Anti-Tumoural Activities Inhibiting Melanoma Tumour Growth in a Preclinical Model

Yessotoxins (YTXs) are a group of marine toxins produced by the dinoflagellates Protoceratium reticulatum, Lingulodinium polyedrum and Gonyaulax spinifera. They may have medical interest due to their potential role as anti-allergic but also anti-cancer compounds. However, their biological activities remain poorly characterized. Here, we show that the small molecular compound YTX causes a slight but significant reduction of the ability of mast cells to degranulate. Strikingly, further examination revealed that YTX had a marked and selective cytotoxicity for the RBL-2H3 mast cell line inducing apoptosis, while primary bone marrow derived mast cells were highly resistant. In addition, YTX exhibited strong cytotoxicity against the human B-chronic lymphocytic leukaemia cell line MEC1 and the murine melanoma cell line B16F10. To analyse the potential role of YTX as an anti-cancer drug in vivo we used the well-established B16F10 melanoma preclinical mouse model. Our results demonstrate that a few local application of YTX around established tumours dramatically diminished tumour growth in the absence of any significant toxicity as determined by the absence of weight loss and haematological alterations. Our data support that YTX may have a minor role as an anti-allergic drug, but reveals an important potential for its use as an anti-cancer drug.

Yessotoxin, a Promising Therapeutic Tool

Yessotoxin (YTX) is a polyether compound produced by dinoflagellates and accumulated in filter feeding shellfish. No records about human intoxications induced by this compound have been published, however it is considered a toxin. Modifications in second messenger levels, protein levels, immune cells, cytoskeleton or activation of different cellular death types have been published as consequence of YTX exposure. This review summarizes the main intracellular pathways modulated by YTX and their pharmacological and therapeutic implications.