I need to know if someone can help me out to find information about a diet to combact cancer cells in humans?

Depends. Diet and exercise may be more important as prevention (eat your veggies) and for recurrence risk rather than actively treating a growing cancer. It may also depend on tumor type, where some cancers are oblivious to dietary interventions. See notes on breast cancer here: http://connection.Asco.Org/commentary/article/id/3075/breast-cancer-diet-exercise-and-treatment-cost.Aspx.
Doesn't exist. There is no proof that any diet can kill cancer cells. Experimentally, diets high in antioxidants have shown some potential, and some advocate high doses of vitamin c or a vegan diet. So far, none of these have translated from animal or cell models to actual people. By all means, a good diet may help your regular cancer treatmentt, but don't expect diet to replace standard therapies.