Newsgroup: it.salute
Titolo: La prossima Generazione dei Farmaci Antitumorali

Ciao, Roby
- - -
The development may explain why people living in countries like Mexico and 
India, who traditionally eat a diet which is very spicy, tend to have lower 
incidences of many cancers that are prevalent in the Western world.
http://www.walesonline.co.uk/news/health-news/tm_headline=spicy-food-could-hold-key-to-beating-cancer&method=full&objectid=18451335&siteid=50082-name_page.html
Spicy food could hold key to beating cancer
Jan 12 2007 Sally Williams, Western Mail
THE chemical in chillies that makes them hot to taste could be used to 
combat cancerous tumours, a new study has found.
Dr Andrew Westwell, a senior lecturer in Medicinal Chemistry at the Welsh 
School of Pharmacy, said the chemical compound capsaicin, that gives spicy 
food like curry its kick, could hold the key to the next generation of 
anti-cancer drugs that will kill tumours.
He was an adviser in a study, published in the journal Biochemical and 
Biophysical Research Communications, that has proven for the first time that 
capsaicin can kill cells by directly targeting their energy source.
Working in collaboration with the University of Nottingham, Dr Westwell said 
the beauty of the laboratory test discovery was that the compound would have 
few or no side effects for the patient.
It could also mean that patients could control or prevent the onset of 
cancer by eating a diet rich in capsaicin.
Dr Westwell said, "We found that in cancer cells grown in the lab, capsaicin 
can be a signalling mechanism that instructs cancer cells to die, without 
the nasty effects of chemotherapy, such as affecting healthy cells or 
changing DNA.
"But with any potential new drug it needs to be thoroughly tried and tested 
for around 10 years - although the advantage we do have is that chillies are 
already eaten by many people and are known to be safe."
Dr Timothy Bates, a member of the Medical Research Council (MRC) College of 
Experts, said the research team also tested similar compounds on pancreatic 
cancer, producing similar cell death to that observed with lung cancer 
cells.
These results are highly significant, as pancreatic cancer is one of the 
most difficult cancers to treat and has a five-year survival rate of less 
than 1%.
Dr Bates added, "As these compounds attack the very heart of the tumour 
cells, we believe that we have in effect, discovered a fundamental 'Achilles 
heel' for all cancers. The investigation and development of 
anti-mitochondrial drugs for cancer chemotherapy by our group is unique in 
the UK and is likely to be extremely significant in man's fight against 
cancer both here and internationally.
"We are currently seeking industrial partners to enable these agents to be 
used in clinical trials to treat a variety of cancers."
The breakthrough was welcomed by Cardiff GP Dr Andrew Dearden, chairman of 
the BMA Welsh GPs Committee.
He said, "This sounds hopeful, although one of the difficulties with cancer 
is that although every few years we get a study that gives out hope, it 
proves difficult to turn into a working drug. But at least the evidence is 
there.
"Obviously there will be a long process to make sure any drug would have 
maximum good bits and minimum bad bits. I don't think we have any drugs that 
have no side effects at all."
But Josephine Querido, information officer at Cancer Research UK, stressed 
that this research did not suggest that eating vast quantities of chilli 
pepper will help prevent or treat cancer. She said, "The experiments showed 
that pepper extracts killed cancer cells grown in the laboratory, but these 
have not yet been tested to see if they are safe and effective in humans."
Cancer Research UK recommends reducing your risk of cancer by eating a 
healthy, balanced diet, with plenty of vegetables and fruit, she said.
So how can chillies kill off cancer cells?
The study has shown that the family of compounds to which capsaicin belongs, 
vanilloids, can kill cancer by attacking the mitochondria of the tumour 
cell, commonly known as its "powerhouse". It which produces ATP, the major 
energy-containing chemical in the body.
By binding proteins in the cancer cell mitochondria the compound triggers 
apoptosis, or natural cell death, without harming the healthy surrounding 
cells.
The development may explain why people living in countries like Mexico and 
India, who traditionally eat a diet which is very spicy, tend to have lower 
incidences of many cancers that are prevalent in the Western world.

max(L) ha scritto:
 > Viceversa negli studi epidemiologici, laddove non si usano
 > topi o colture cellulari, (e.g. Messico vedi sopra) l'eccessivo uso
 > di peperoncino sembrerebbe correlato ad un aumento nell'incidenza
 > di cancro allo stomaco (2)
Vabbe', non dico di no. Ma valuta che in Messico i peperoncini,
tenuti in casa o nel retrobottega in un clima tropicale, sono
spessissimo contaminati dai funghi Aspergillus sp., che producono
potenti agenti cancerogeni (aflatossine ed ocratossine).
In quella ricerca (2) questo aspetto non e' stato minimamente
preso in considerazione. Inoltre nel full text di quella ricerca,
la tabella III 'Potential related factors for gastric cancer risk'
ci da' p-value 0.079 per la capsaicina ma p-value 0.032 per
le carni conservate e 0.030 per l'etanolo. Si direbbe che
la Tequila sia un fattore di rischio peggiore dei peperoncini.
Bye,
   *GB*

   discordanti (1)
(scritto di con copia/incolla di pugno suo)
Da che pulpito!!!
Cioe' tu ritieni che ogni articolo postato su it.salute, che e' zeppo della 
tua immondizia e di quella dei tuoi compagni di merende, debba rispondere a 
criteri rigorosamente scientifici, a risultati gia' acquisiti e comprovati? 
Questi sono i risultati di ricerche tuttora in corso, solo che sono il tipo 
di ricerca che tanto da fastidio a te, alla tua congrega ed al tuo diabolico 
datore di lavoro.
Cosa vuoi poi la carta da bollo e la registarzione del documento presso un 
notaio?
Ma vai a cagare imbecille.
PS:
E cerca di scrivere in modo che la gente possa capire, il tuo slang da 
medico fallito e' in disuso, coglione. 

  E dove l'hai letto che sono ancora in corso ?
E tu dove hai letto che non sono piu' in corso? 

max(L) ha scritto:
 >> spessissimo contaminati dai funghi Aspergillus sp., che producono
 >> potenti agenti cancerogeni (aflatossine ed ocratossine).
 >
 >   questo e' interessante ma sarebbe piu' interessante ancora
 >   sapere quali specie di aspergillus (indipendentemente dalla
 >   generica indicazione sp.),
Prevalentemente Aspergillus flavus:
 
http://www.ncbi.nlm.nih.gov/pubmed/15770456
   Mycopathologia. 2005 Feb;159(2):291-8.
  Fungal contamination of some imported spices.
   Mandeel QA.
  (...) The most heavily contaminated spice samples examined
  were observed in red chili and black pepper in order of magnitude
  of 1580 and 1120 cfu/g, respectively. The most predominant
  fungal genera encountered were Aspergillus, Penicillium, Rhizopus,
  Cladosporium and Trichoderma. Yeasts were also frequently recovered,
  but not identified. Relative occurrence values of taxa disclosed
  ranged between 36.4% for A. flavus and 0.6% for A. parasiticus and
  Absidia corymbifera. (...)
 >   il livello di contaminazione da aflatossine
Sembra molto alto nel chili in pasta e in polvere (presumo
che sia piu' basso nei peperoncini calabresi):
 
http://www.ncbi.nlm.nih.gov/pubmed/8885323
   Food Addit Contam. 1996 Oct;13(7):833-41.
  Survey of ethnic foods for mycotoxins.
   Patel S et al.
  A survey has been carried out in the UK to determine the levels
  of mycotoxins in a range of ethnic foods. (...)
  Aflatoxins, ochratoxin A and fumonisins were found in chili paste
  and zearalenone and ochratoxin A in curry pastes. The highest
  mycotoxin levels and frequency of occurrence were in chili powder,
  curry powder and ginger.
 >   e se queste sono in grado di indurre cancro allo stomaco
 >   e non solo epatocarcinomi.
Questo e' piu' difficile da stabilire. Le associazioni con il cancro
allo stomaco che vanno per la maggiore sembrano essere con H. pylori
(che pero' in India e' frequentissimo, per cui la situazione paradossale
e' detta "Enigma Indiano") e con il contenuto di sale degli alimenti,
ma questo studio sperimentale rende indiziata anche la sterigmatocistina
prodotta da A. flavus:
 
http://www.ncbi.nlm.nih.gov/pubmed/12206820
   Toxicol In Vitro. 2002 Oct;16(5):531-7.
  Inhibition of vacuolation toxin activity of Helicobacter pylori
  by iodine, nitrite and potentiation by sodium chloride,
  sterigmatocystin and fluoride.
   Ma F et al.
  The toxin VacA produced by Helicobacter pylori is an important
  determinant of virulence. VacA causes vacuolation of cultured cells
  such as HeLa cells. Iodine, nitrite, sodium chloride, thiocyanate
  and fungus toxin sterigmatocystin are universally present in nature
  and could possibly be related to carcinogenesis of the stomach.
  The present study was designed to examine the effects of the
  above-mentioned compound on VacA-induced vacuolation of HeLa cells,
  which was quantitated using the neutral red uptake assay. VacA-induced
  vacuolation was inhibited by BafA1 and NPPB. Formation of large
  vacuoles was inhibited in the presence of iodine, nitrite, but enhanced
  by sodium chloride, thiocyanate, fluoride and sterigmatocystin.
  Our results indicate that VacA toxin may interact with other gastric
  cancer risk factors present naturally in the environment, and suggest
  that those compounds may modulate the development of gastric cancer
  induced by H. pylori.
 >   Se guardi quindi ai risultati della regressione logistica
 >   espressi in termini di odds-ratio (Tabella V) e' evidente
 >   come il rischio aumenti proporzionalmente all'aumentare
 >   della concentrazione di capsaicina a sfavore dei casi
 >   da 1.0 (per il livello di riferimento 0-29.9) a 1.60
 >   (per il livello 30-89.9) a 1.71 (terza classe, 90-250).
A parte che insieme alla capsaicina aumentano anche le micotossine,
lascia che io ti dica che cosa ne penso...
La capsaicina e' una sostanza dalle caratteristiche irritanti
molto peculiari, in grado di dare sensazioni non corrispondenti
al danno reale provocato, che sembra inesistente a piccole dosi,
ma non ad alti dosaggi. Ora, siccome lesioni e infiammazioni croniche
sono proprio cio' che ci vuole per indurre l'insorgenza di tumori,
la mia opinione e' che mangiare 9-25 peperoncini al giorno (come
fanno in Messico) danneggi la mucosa gastrica e quindi aumenti
il rischio di cancro, mentre un consumo piu' ragionevole (come
in Calabria e anche in India, visto che li' il resto del piccante
e' dato dalla curcuma e altre spezie) potrebbe risultare protettivo
aumentando il tasso di apoptosi di cellule anomale, come si e' visto
nelle esperienze con la capsaicina in vitro.
Ribadisco percio' il mio scetticismo a riguardo delle estrapolazioni
fatte a partire dai dati statistici, perche' in assenza di chiari
e verificati meccanismi patogenetici, non e' possibile eliminare
tutti i fattori di confondimento. Che dire se in India l'effetto
cancerogeno delle micotossine venisse contrastato dal fatto che
l'ingrediente principale del curry e' la curcuma? Vedi:
 
http://www.ncbi.nlm.nih.gov/pubmed/17454112
   Food Addit Contam. 2007 Apr;24(4):391-7.
  Suppression of ochratoxin biosynthesis by naturally
  occurring alkaloids.
   Lee SE et al.
  The effects of four alkaloids on the biosynthesis of ochratoxin A
  (OTA), ochratoxin B (OTB) and citrinin were examined on four
  OTA-producing aspergilli: Aspergillus auricomus, A. sclerotiorum
  and two isolates of A. alliaceus. (...)
  Curcumin, a constituent of tumeric, completely inhibited mycelial
  growth of A. alliaceus isolate 791 at 0.1% (w/v) and decreased OTA
  production by approximately 70% at 0.01% (w/v). (...)
Bye,
   *GB*

max(L) ha scritto:
 >   le statistiche non servono a nulla se il disegno sperimentale
 >   che le ha originate e' distorto: non e' una faccenda di
 >   estrapolazione ma di validita' dell'inferenza che
 >   dipende dall'aver disegnato lo studio in modo corretto
 >   per rispondere alle domande che ci si era posti.
Ecco! Mi pare che con parole piu' professionali hai detto
cio' che io intendevo esprimere, sostanzialmente.
 >   E questo non vale solo per gli studi di tipo epidemiologico
 >   ma anche per gli esperimenti di laboratorio, laddove si
 >   studiano i meccanismi patogenetici a cui fai riferimento.
E' vero.
 >   Infine per i fattori di confondimento si parla di aggiustamento
 >   perche' per lo piu' sono per loro natura ineliminabili.
Tuttavia, finche' restano ineliminati, le conclusioni non sono
davvero scientifiche come invece in fisica e in chimica.
 >   non spiegherebbe perche' l'incidenza di cancro allo stomaco
 >   in India e' simile a quello che si osserva in Danimarca e USA.
In Danimarca e Usa la sieropositivita' a H. pylori e' bassa,
mentre in India e' altissima. Di conseguenza, l'incidenza
di cancro gastrico in India dovrebbe essere molto alta, e
invece risulta ai minimi valori mondiali. Questo significa
che, o la correlazione fra H. pylori e carcinoma gastrico
e' un colossale abbaglio, oppure che qualcosa nella dieta
indiana risulta protettivo a questo riguardo.
Tutto e' possibile comunque:
 
http://www.ncbi.nlm.nih.gov/pubmed/16552799
   World J Gastroenterol. 2006 Mar 7;12(9):1346-51.
  Causal role of Helicobacter pylori infection in gastric cancer:
  an Asian enigma.
   Singh K, Ghoshal UC.
  Helicobacter pylori (H pylori) has been etiologically linked to
  gastric cancer. H pylori infection is more frequent in less developed
  Asian countries like India, Bangladesh, Pakistan, and Thailand and
  is acquired at early age than in more developed Asian countries like
  Japan and China. Frequency of gastric cancer, however, is very low
  in India, Bangladesh, Pakistan and Thailand compared to that in Japan
  and China. Similar enigma has been reported from Africa as compared
  to the West. Seroprevalence of H pylori infection in adult populations
  of India, Bangladesh, Pakistan and Thailand varies from 55% to 92%.
  In contrast, seroprevalence of H pylori in Chinese and Japanese adults
  is 44% and 55%, respectively. Annual incidence rate of gastric cancer
  in India, Bangladesh, and Thailand is 10.6, 1.3, 7.1 per 100,000
  populations, respectively; in contrast, that in China and Japan is
  32-59 and 80-115 per 100,000 populations, respectively. Several studies
  from India failed to show higher frequency of H pylori infection in
  patients with gastric cancer than controls. Available evidences did
  not support difference in H pylori strains as an explanation for this
  enigma. Despite established etiological role of H pylori, situation
  is somewhat enigmatic in Asian countries because in countries with
  higher frequency of infection, there is lower rate of gastric cancer.
  Host's genetic make-up and dietary and environmental factors might
  explain this enigma. Studies are urgently needed to solve this issue.
Bye,
   *GB*