Transmitting video signal, if you don't have a 75Ω coax, can be tricky.
So in your case, I assume that the distance is not longer than 10-20m, you can try to connect video signal using standard electrical wires, but, because the cables are unshielded, you should connect a Transient Voltage Suppressor rated for very small voltages (+/-5V) or connect 2-3 signal diodes, such as 1N4148 (or similar), in on direction and 2-3 in the other direction, and this should protect the cables against external interferences.
Better option is to use shielded twisted pairs in balanced or even unbalanced configuration. So if you have a cable like mentioned CAT-5, this will be the preferred option.
The first sign that something is wrong will be the Black&White image. This means that your line can not transmit a colour signal due to frequency loses in the higher part of the video band, but if you haven't experienced anything like this, I will not elablorate on this in advance ..
Good luck and regards ..
IanP