If you already have fruit or flower clusters on it, you can simply cut the growing tip of that shoot so it doesn't grow anymore, but be aware you sacrifice any further fruit higher up, unless you have suckers growing on that branch/vine.

In cooler climates, we sometimes cut the main vine growing tip sometime in August to stop vegetative growth and start ripening existing fruits already on the plant.

Hope this helps.

Simply pinch or cut off the "growing tip" at the top of the plant. That's the part with the teeny-tiny leaves and teeny-tiny flower buds.

The plant will continue to form suckers where each leaf joins a stem; you must be pinching most of the suckers now or the picture wouldn't show such a tall, skinny plant. By the way, there's nothing evil about suckers; it's just the plant's normal way of forming branches. Suckers have leaves and flowers and eventually fruit, just as the main stem does. [Suckers even have their own suckers.]

I let some of the lower suckers develop in hopes that the plant won't grow taller than I can reach quite so quickly. But a bushier plant does require a different method of support.

You place a stem just below the terminal bud between your thumbnail and forefinger and then exert enough pressure so that the thumbnail slices the tip off. Incidentally, that won't stop fruit or roots from growing.