Researchers found that the black substance used by cuttlefish to frighten the predators contains something interesting, which are nanoparticles that could inhibit the increase of cancerous tumors in mice. Pang-Hu Zhou, a researcher from the Renmin Hospital of Wuhan University and Xian-Zheng Zhang from the Chemistry Department at Wuhan University, made a work about the ability of nanoparticles from cuttlefish ink to absorb tumor evolution in a recent issue of ACS Nano.
They declared that they found nanoparticles from cuttlefish ink with decent biocompatibility that can successfully reach tumor immunotherapy and photothermal therapy at the same time. Also, they believed that this finding might be an inspiration for further studies.
Tumor immunotherapy implies fighting with cancer by stimulating the body’s own immune system and one strategy is represented by targeting the leukocytes, or white blood cells. Well-known leukocytes, because of its predominance in some tumors, are the macrophages, existing in one or two forms, M1 or M2.
The M1 is the most dangerous one because its phenotype submerges and terminates tumor cells through the development of phagocytosis and with the initiation of T cells (more white cells). On the other hand, when it comes to M2, things are more different in a way in which the M2 phenotype only suppresses the immune function, also allowing tumor growth to continue unchecked. But an interesting fact is that, the M2 phenotype always succeeded to outnumber the M1 phenotype.
Researchers though, try to create a development of small molecules and antibodies that can swift protumor M2 macrophages to antitumor M1 macrophages. Also, they are creating nanoparticles such as photothermal agents that, when they’ll face irradiation, to destroy locally the cancer cells by thermal ablation. These agents, however, can be put into synthesized nanoparticles, and then possibly administrated to patients.
The only thing is that these synthetic nanoparticles are very expensive and need advanced preparation methods, that’s why some researchers choose nature as an alternative. Certain natural compounds, as some researches show, including the ones found in brown algae and some other bacteria, contain polysaccharides that have the skill to change macrophages from M2 type to the M1 type.
The nanoparticles from the cuttlefish ink are spherical and approximately 100 nm in diameter, also they have that skill, too and it’s verified by performing many experiments both in vitro with tumor cells and in vivo with tumor-afflicted mice.
The in vitro experiments helped researchers found that irradiating the nanoparticles with almost-infrared irradiation killed approximately 90% of tumor cells, even if the nanoparticles showed almost no cytotoxicity without irradiation. Researchers explanation? Well, it’s simple, the high melanin content of the nanoparticles has an important role in the irradiation process, as melanin has an intrinsically good photothermal conversion skill.
But what about mice? Nanoparticles treatment in them showed their effectiveness both alone and in combination with irradiation, although irradiation further increased the outcome. Bioluminescent imaging exposed the fact that the treated mice exhibited significantly decreased tumor bioluminescence compared to controls, showing greatly reduced metastases on internal organs. Mice treated with both nanoparticles and irradiation displayed a nearly full inhibition of tumor growth.
With the help of a gene analysis, the researchers identified 194 differentially expressed genes involved in immune functions that were related with the directive of the inflammatory response and cell destroying, and which were wither up or down, regulated by the treatment.
The analysis showed that a particular signaling pathway is accountable for the changing of M2 macrophages to M1 macrophages. This mechanism not only leads to phagocytosis of tumor cells, but also stimulates the immune system to create various antitumor factors, all of which have an important role in inhibiting tumor increase. For the future, the researchers want to explore other natural materials that contain anti-cancer properties.
Zhang also stated that, his research team is right now exploring the biomedical potential of natural materials such as hair, cuttlefish ink, bacteria, fungi, and even the cells of the human body as a therapeutic drug shipper. He believes that the inspiration from nature is all we need and taking advantage of its own properties will help us find some valuable research that will deliver new and effective solutions for the treatment of clinical diseases.
Laura grew up in a small town in northern Quebec. She studied chemistry in college, graduated, and married her husband one month later. They were then blessed with two baby boys within the first four years of marriage. Having babies gave their family a desire to return to the old paths – to nourish their family with traditional, homegrown foods; rid their home of toxic chemicals and petroleum products; and give their boys a chance to know a simple, sustainable way of life. They are currently building a homestead from scratch on two little acres in central Texas. There’s a lot to be done to become somewhat self-sufficient, but they are debt-free and get to spend their days living this simple, good life together with their five young children. Laura is an advocate for people with disabilities.