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+--- Thread: Mystery of cancer triggers + Ants help explain why our brains shrank millennia ago (/thread-11177.html)
Mystery of cancer triggers + Ants help explain why our brains shrank millennia ago - C C - Oct 24, 2021
Mystery of the environmental triggers for cancer deepens
https://www.theguardian.com/science/2021/oct/24/mystery-of-the-environmental-triggers-for-cancer-deepens
EXCERPTS: Scientists will have to rethink how environmental triggers allow tumours to form and develop, one of Britain’s leading cancer experts warned last week. Michael Stratton, director of the Wellcome Sanger Institute, said recent results from an international cancer research study – which aimed to pinpoint environmental triggers involved in oeosophageal cancer – indicated current scientific understanding of tumour formation was inadequate.
The research – on a type known as oesophageal squamous cell carcinoma – was aimed at uncovering why certain parts of the world suffer extremely high rates of the disease. These areas include parts of Iran, Turkey, Kenya and China where the disease is the most common form of cancer. In many other parts of the world, its incidence is relatively low.
The study, published last week in Nature Genetics, indicates that scientists will have to think more broadly about the factors that cause cancer, Stratton added.[...] “Yes, external factors can trigger oesophageal squamous carcinoma – but not by directly causing mutations. In other words, we have found evidence that chemicals might be able to work in different ways other than directly causing mutations to increase a person’s chances of developing cancer. That is the message we need to take from this study – which has been backed by experiments on animals. We will have to rethink our ideas about the way in which some cancers develop. It is a crucial lesson.” (MORE - missing details)
Ants could help explain why our brains mysteriously shrank thousands of years ago
https://www.sciencealert.com/ants-could-help-explain-why-our-brains-mysteriously-shrank-thousands-of-years-ago
EXCERPTS: In the 6 million years since our ancestors first branched off from our ancient primate relatives, the volume of the human brain has nearly quadrupled. What many people don't realize, however, is that sometime after the last ice age, that very brain actually began to shrink.
The result is that today, our brains are slightly smaller than those of early humans living 100,000 years ago, and yet no one really knows when or why this happened. Now, a biological anthropologist, a behavioral ecologist, and an evolutionary neurobiologist have put their heads together and offered up an intriguing new hypothesis.
It's based on the evolutionary history of a brain a million times smaller than our own: that of the humble ant. [...] When researchers analyzed models of the brain size, structure, and energy use of worker ants, they found evidence the organ had adapted to become more efficient in social groups. Perhaps, the authors suggest, the human brain has been similarly shaped by collective intelligence, where knowledge can be shared and distributed among a colony or community.
With the dawn of human society, they further explain, human knowledge could be externalized and passed on to others in the group, distributing information among multiple people instead of storing it all in each person. The cutting of this 'intellectual fat' could, theoretically, free up the brain to become more efficient at a smaller number of jobs... (MORE - missing details)
PAPER: https://doi.org/10.3389/fevo.2021.742639
RE: Mystery of cancer triggers + Ants help explain why our brains shrank millennia ago - Magical Realist - Oct 25, 2021
List of known carcinogens. One that stood out is Chinese style salted fish. Known for causing nasophageal cancer. Don't know if this a common food in China, but it may play some role.
Acetaldehyde (from consuming alcoholic beverages)
Acheson process, occupational exposure associated with
Acid mists, strong inorganic
Aflatoxins
Alcoholic beverages
Aluminum production
4-Aminobiphenyl
Areca nut
Aristolochic acid (and plants containing it)
Arsenic and inorganic arsenic compounds
Asbestos (all forms) and mineral substances (such as talc or vermiculite) that contain asbestos
Auramine production
Azathioprine
Benzene
Benzidine and dyes metabolized to benzidine
Benzo[a]pyrene
Beryllium and beryllium compounds
Betel quid, with or without tobacco
Bis(chloromethyl)ether and chloromethyl methyl ether (technical-grade)
Busulfan
1,3-Butadiene
Cadmium and cadmium compounds
Chlorambucil
Chlornaphazine
Chromium (VI) compounds
Clonorchis sinensis (infection with), also known as the Chinese liver fluke
Coal, indoor emissions from household combustion
Coal gasification
Coal-tar distillation
Coal-tar pitch
Coke production
Cyclophosphamide
Cyclosporine (ciclosporin)
1,2-Dichloropropane
Diethylstilbestrol (DES)
Engine exhaust, diesel
Epstein-Barr virus (EBV) (infection with)
Erionite
Estrogen-only menopausal therapy
Estrogen-progestogen menopausal therapy (combined)
Estrogen-progestogen oral contraceptives (combined) (Note: There is also convincing evidence in humans that these agents confer a protective effect against cancer in the endometrium and ovary)
Ethanol in alcoholic beverages
Ethylene oxide
Etoposide
Etoposide in combination with cisplatin and bleomycin
Fission products, including strontium-90
Fluoro-edenite fibrous amphibole
Formaldehyde
Haematite mining (underground)
Helicobacter pylori (infection with)
Hepatitis B virus (chronic infection with)
Hepatitis C virus (chronic infection with)
Human immunodeficiency virus type 1 (HIV-1) (infection with)
Human papilloma virus (HPV) types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 (infection with) (Note: The HPV types that have been classified as carcinogenic to humans can differ by an order of magnitude in risk for cervical cancer)
Human T-cell lymphotropic virus type I (HTLV-1) (infection with)
Ionizing radiation (all types)
Iron and steel founding (workplace exposure)
Isopropyl alcohol manufacture using strong acids
Kaposi sarcoma herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8) (infection with)
Leather dust
Lindane
Magenta production
Melphalan
Methoxsalen (8-methoxypsoralen) plus ultraviolet A radiation, also known as PUVA
Methyl-CCNU
4,4'-Methylenebis(chloroaniline) (MOCA)
Mineral oils, untreated or mildly treated
MOPP and other combined chemotherapy including alkylating agents
2-Naphthylamine
Neutron radiation
Nickel compounds
N'-Nitrosonornicotine (NNN) and 4-(N-Nitrosomethylamino)-1-(3-pyridyl)-1-butanone (NNK)
Opisthorchis viverrini (infection with), also known as the Southeast Asian liver fluke
Outdoor air pollution (and the particulate matter in it)
Painter (workplace exposure as a)
3,4,5,3',4'-Pentachlorobiphenyl (PCB-126)
2,3,4,7,8-Pentachlorodibenzofuran
Pentachlorophenol
Phenacetin (and mixtures containing it)
Phosphorus-32, as phosphate
Plutonium
Polychlorinated biphenyls (PCBs), dioxin-like, with a Toxicity Equivalency Factor according to WHO (PCBs 77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169, 189)
Processed meat (consumption of)
Radioiodines, including iodine-131
Radionuclides, alpha-particle-emitting, internally deposited (Note: Specific radionuclides for which there is sufficient evidence for carcinogenicity to humans are also listed individually as Group 1 agents)
Radionuclides, beta-particle-emitting, internally deposited (Note: Specific radionuclides for which there is sufficient evidence for carcinogenicity to humans are also listed individually as Group 1 agents)
Radium-224 and its decay products
Radium-226 and its decay products
Radium-228 and its decay products
Radon-222 and its decay products
Rubber manufacturing industry
Salted fish (Chinese-style)
Schistosoma haematobium (infection with)
Semustine (methyl-CCNU)
Shale oils
Silica dust, crystalline, in the form of quartz or cristobalite
Solar radiation
Soot (as found in workplace exposure of chimney sweeps)
Sulfur mustard
Talc containing asbestiform fibres
Tamoxifen (Note: There is also conclusive evidence that tamoxifen reduces the risk of contralateral breast cancer in breast cancer patients)
2,3,7,8-Tetrachlorodibenzo-para-dioxin (TCDD); "dioxin"
Thiotepa
Thorium-232 and its decay products
Tobacco, smokeless
Tobacco smoke, secondhand
Tobacco smoking
ortho-Toluidine
Treosulfan
Trichloroethylene
Ultraviolet (UV) radiation, including UVA, UVB, and UVC rays
Ultraviolet-emitting tanning devices
Vinyl chloride
Welding fumes
Wood dust
X- and Gamma-radiation