Try using the sortrows command in conjunction with a transpose. Apply it once to exploit column sorts (e.g. Column 1 is Row 1 above), and then again after the sort to put it back into the dimensions you want.
a = [5 8 1 2 7 6 3 4
70 60 50 40 30 20 10 0]
sorted_a = sortrows(a.',1).'