Is liver cancer fatal? Yes of course! If someone has liver cancer, then we think that he is not far from death. People are dread to think and avoid talking about cancer, because the degree of malignancy is high and the mortality rate is high. So what are the factors cause liver cancer?
According to the epidemiological study, liver cancer is closely related to viral hepatitis, cirrhosis, aflatoxin, long-term drinking, water sources contaminated by algal toxins, genetic factors, and some chemical carcinogens. In China, aflatoxin and chronic viral hepatitis are the main causes of liver cancer.
What is aflatoxin? What foods contain aflatoxin?
Aflatoxin is a secondary metabolite mainly produced by Aspergillus flavus and parasitic molds, and aflatoxin contamination is likely to occur in foods and feeds in hot and humid regions. They are often found in food and oil products such as peanuts, corn, soybeans, rice, and wheat. Aflatoxin poses a serious threat to human health and life for its great toxicity. In the next, we will share a real story.
In the 1960s, there were 100,000 turkeys died suddenly in the UK. At that time, it shocked the whole world. In the later, the investigation found that it was related to the peanut meal imported from Brazil. The peanut meal that these dead turkeys eat is the residue extracted from the peanut oil. The researchers found a large amount of aflatoxin and its metabolite aflatoxin in these peanut meals. Peanut meal is rich in protein and is a good feed for poultry. After being contaminated by a large amount of Aspergillus, it became the "culprit" of killing 100,000 turkeys. Besides, in 1961, there was a report that rats are infected with primary liver cancer, after feeding with feed contaminated with aflatoxin in 30 weeks later. Since then, aflatoxin has attracted the attention of scientists and carried out researches more extensive and in-depth.
According to research reports, there are more than a dozen in the class of aflatoxin, of which B1, B2, G1, and G2 are the representative of aflatoxin appeared in agricultural products mainly. If the agricultural products containing B1 and B2 are eaten by the cows, some of them will be converted into M1 and M2 in milk. The product of conversion is the main source of aflatoxin in milk. For example, in 2011 the State Administration of Quality Supervision Inspection and Quarantine announced the results of sampling in the inspection of liquid milk products nationwide. A batch of products produced by Mengniu Dairy (Meishan) Co., Ltd. was found to exceed 140% of the standard in aflatoxin M1. Mengniu Vice President explained that Meishan is located in Sichuan with rainy weather and some suppliers have improper management of feed. This condition is suitable for mildew growth and producing aflatoxin in milk. Therefore, to be healthy everyone should take precautions in food safety, stay away from toxic, and harmful foods.
How much is the toxicity of aflatoxin? How harmful is it to the body of human or animal?
In 1993, aflatoxin was classified as a Class A carcinogen by the World Health Organization's Cancer Research Institute, and it is a highly toxic substance. Its toxicity second to botulinum is 68 times that of arsenic. It mainly causes different degrees of damage to the liver of humans and animals. After aflatoxin enters the human body, it is mainly metabolized under the action of the endoplasmic reticulum microsomal oxidase with the mixed functions of hepatocytes. The toxicity of aflatoxin after metabolism is much higher than that of cyanide, arsenide and organic pesticides. Aflatoxin B1 (AFB1) is the most toxic class. When the body ingests AFB1 in large quantities, it can cause acute poisoning, acute hepatitis, hemorrhagic liver necrosis, hepatic steatosis, and bile duct hyperplasia. When the body ingests a small amount of ingestion continually, it may cause chronic poisoning, growth disorders, fibrotic lesions causing proliferation in fibrous tissue and even death in the severe case.
Scientists have also carried out a lot of research for aflatoxins, especially the highly toxic substances AFB1 and found out the general mechanism causing liver cancer. When AFB1 enters the body, it can form AFB1-N7-guanine adduct. Besides, the AFB1-lysine adduct may also be formed in the blood, and the two adducts are the main markers of aflatoxin. On further research, the AFB1-N7-guanine adduct has a strong biological effect, which can chemically and biologically form a more stable AFB1 formamide adduct lasting longer in the body. AFB1-N7-guanine adduct and AFB1 formamide adduct may be the main form of AFB1 toxic, effecting in the body.
Related studies have also reported the toxic effects of these adducts in humans. A study reported that by detecting the AFB1-albumin adducts in the serum of 20 patients with liver cancer and 86 healthy people, it was found that 65% of patients with liver cancer were positive, and the positive rate of healthy people was only 37%. It is proven that AFB1-albumin adducts have a great effect on carcinogenesis. Besides, a study on hepatitis B virus carried out in Taiwan and Guangxi also has shown that AFB1-N7-guanine adduct and AFB1-albumin adduct are positive. The people with liver cancer are of a higher incidence than other groups. Therefore, AFB1-related adducts have a great effect on inducing human liver cancer.
According to related research reports, the hepatitis B virus and AFB1 have a synergistic effect. It will produce a large amount of AFBI, which is equivalent to ingest the excessive consumption of foods containing AFB1. If people have hepatitis B, their chances of developing liver cancer will increase greatly.
How can we prevent it from harming us?
Aflatoxin is almost ubiquitous in agricultural products, and humans ingested it more or less. Therefore, all countries in the world have set a limited standard according to their national conditions. The danger can be neglected under that standard. In China's AFB1 permissible standard in food (GB 2761-2011) is in the following. Corn, peanut kernels and peanut oil should not exceed 20 ug/kg. Rice and edible oil should not exceed 10 ug/kg. Other food, beans, and fermented food beyond 5 ug/kg. Therefore, to reduce unnecessary damage to the body, we should try our best to make a healthy diet, try to keep the food in a dry and ventilated place and get away from grain and oil products in the mold such as peanuts, corn, and wheat.
In summary, there are many inducements and pathogens of liver cancer, but the carcinogenicity of aflatoxin can not be ignored. The carcinogenicity of aflatoxin is too toxic and too close to us, and if you don't pay attention at one time, you will get sick from the food you eat. Therefore, by understanding the mechanism and pathway of aflatoxin carcinogenesis, it can be a good guide for people to reduce the pollution or intake of aflatoxin in daily life and play an active and effective role in the prevention of liver cancer.