Yes, but cats love routine, and follow it as much as possible, like a clock.
You can train a dog to respond a certain ways to certain signals, but you can't train it to wake you up every day at a certain specific time, unless it can recognise some signal. But cats will train themselves to do that, if they get something out of it, and are by nature well aware of the time of day, with surprising precision.
Of course, if you train your cat to wake you up for work, better be ready to be woken up at the same time on weekends, unless there's some noticeable enough difference (like traffic noise on the street outside) between workdays and holidays and you're lucky to have a sufficiently smart cat who can notice the difference. Cats might be quite adequate clocks, but they're not calendars.