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! Fucosyl!or!sialosyl6fucosyl,!Lewisx!and!sialosyl!Lewisx,!sialosyl6dimeric!Lex,!
Lea,!monosialosyl!Lea!(CA!1969),!disialosyl!Lea,!Tn,!sialosyl6Tn,!galactose,!and!ß166!
branched! oligosaccharides! antigens! (see! their! structures! in! reviews)! (163,5)! have!
been! investigated/determined! by! monoclonal! antibody,! lectin! or! other! assays! in!
relation! to! invasive! capacity,! metastatic! potential,! prognosis! or! survival! of!
colorectal!operated!patients.!

! We! have! found! remarkable! differences! in! the! reactivity! of! the! assayed!
lectins! (see! Table! II).! In! addition,! the! reactivity! profile! shows! a! parallelism!
between!SNA!and!MAL!II,!both!at!467!days!and!769!months!after!exeresis,!probably!
due!to!the!fact!that!both!lectins!have!similarity!for!their!specificities,!as!indicated!in!
the! Table.! As! expected,! their! reactivities! differ! from! those! of! the! other! assayed!
lectins.! Precisely,! this! different! behaviour! could! suggest! the! possibility! of! choice!
and!the!selection!for!use!as!analytical!tools!of!certain!lectins!such!as!SNA,!LEL!and!
LTL,! whose! profiles! of! reactivity! are! not! parallel.! In! fact,! SNA! shows! similarly!
increased! values! (20625%! in! comparison! to! controls),! both! at! 467! days! and! 769!
months,! while! LEL! shows! a! 20%! increased! value! at! 467! days! but! only! a! 6%!
increased! value! at! 769! moths,! and! finally! LTL! exhibits! a! decrease! of! 37%! at! 467!
days! and! shows! not! significant! difference! in! comparison! to! control! at! 769! months!
after!surgery.!

! A! possible! correlation! between! these! results! and! the! structure! of! certain!
antigens!could!be!tentatively!suggested!as!follows:!SNA!reactivity,!with!sialosyl6Tn;!
LEL,!with!sialosyl!Lea;!and!LTL,!with!Lex,!difucosyl!Lex!and!sialosyl!Lex.!

! Finally,! although! glycan! moieties! of! glycoconjugates! are! not! specific!
markers! for! serological! detection! of! colorectal! cancer,! they! occur! in! large!
concentrations! in! serum! from! cancer! patients! due! to! «either! (a)! increased!
biosynthesis! of! pre6existing! “normal”! molecules,! which! in! normal! tissue! are!
present!in!small!or!even!undetectable!amounts»!(18),!or!(b)!the!emergence!of!new!
molecules!with!altered!glycosylation!patterns!(“aberrant!structures”).!

! Monoclonal! antibodies! and! lectins! could! be! useful! tools! for!
detection/determinationn! of! both! kinds! of! molecules:! those! with! “normal”!
structure!(whose!concentration!increases!in!pathological!circumstances)!and!those!
with!“aberrant”!structure.!

! Since!many!lectins!are!now!commercially!available!(at!a!relatively!low!cost)!
and! the! procedures! for! their! measure! are! very! simple,! they! may! be! considered! as!
promising! techniques! in! this! view.! However,! the! correlation! between! long! term!
clinical! evolution! and! lectin! binding! level! will! have! to! be! ascertained! for! each!
patient!in!order!to!validate!these!indicators!for!treatment!monitoring.!

126$

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