I finally manage to do the tricks with these:

uppercase the first letter and lowercase the rest 
  $string = "\u\L$string";

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my string always contains spaces and/or dashes so I uppercase each letters which follows one or more spaces or dashes. 
  $string =~ s/([\s-]+)(.)/$1\u$2/g;

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Regards, Frederic

In reply to Re^2: regexp on utf8 string by fredvdv
in thread regexp on utf8 string by fredvdv

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