Are there any natural cures for enlarged prostates?

Yes. Some people find benefit from herbal medications that typically contain saw palmetto. More often than not, it doesn't help as much as prescription drugs do though.
Yes. The national institutes of health states saw palmetto is of comparable effectiveness to the drug proscar, (finasteride) but has less side effects. Pygeum is also very effective. Beta-sitosterol, stinging nettle, lycopene & grass pollen are also proven to help. Zinc is essential for prostate health & prevents enlargement. See http://www.Livestrong.Com/article/109702-natural-herbs-treat-prostate-enlargement/.