What do you to make sure a pound cake stays in the tube pan and not escape out of bottom?

Use a springform pan. Springform pans are designed with a removable bottom, which makes it easy to remove a pound cake without it sticking.

Grease the pan thoroughly. Be sure to grease all of the nooks and crannies of the pan, especially the bottom and the sides. This will help to prevent the cake from sticking.

Add a tablespoon of flour to the bottom of the pan. This will help to create a barrier between the cake and the pan, and will also help to absorb any excess moisture from the cake.

Bake the cake at the correct temperature. If the cake is baked at too low of a temperature, it may not cook through properly and will be more likely to fall.

Let the cake cool completely in the pan before removing it. This will help to prevent the cake from breaking or falling apart.