From: B C on
Couldn't you just access the elements of the cell and reassign them to a some matrix?
Simple example:

>> x = [2,2];
>> y = [1,2,3;4,5,6];
>> c1{1} = x
c1 =

[1x2 double]

>> c1{2} = y

c1 =

[1x2 double] [2x3 double]

>> m = c1{1}

m =

2 2

>> n = c1{2};
>> n

n =

1 2 3
4 5 6