Variable DC Supply "Ignoring" Potentiometer
Unfortunately, this PCB is unlikely to ever work. You will need to redesign it.

Switching power supply designs are very sensitive to layout. In particular, it's critical to minimize the area and inductance of the current loop. Unfortunately, your design places the inductor rather arbitrarily, which leaves the current loop all over the place. For more information on these aspects of design, you may want to read some application notes on switching PSU design, such as:


Linear Technology: PCB Layout Considerations for Non-Isolated Switching Power Supplies
TI: Five Steps to a Good PCB Layout of a Boost Converter


I also see a couple of generic issues with your PCB design, including:


Your layout is not making use of its ground pour. A good ground is critical for all circuits, but is particularly important for a power supply design.
One of the terminals of C1 appears to be unrouted.
As other users have mentioned, it looks like you may have chosen some parts which are not rated for the voltages you're trying to produce.
You are using rather arbitrary packages and footprints for a lot of parts. For instance, you're using a Kelvin resistor footprint for RSENSE1, but ignoring the kelvin terminals, and it almost looks like you've soldered an electrolytic capacitor to a SMD capacitor footprint on the back side. Switching power supplies are sensitive to lead inductance; these choices matter!