Rag2-/- mice are more immunodeficient than nude mice, though both show highly activated NK. However, few literature reported human-derived tumor bearing Rag2-/- for cancer diagnostics and therapeutics. Is it proper to establish human-derived cancer model on Rag2-/-?
Yes, Rag-deficient models can and have certainly been used to establish human cancer models. However, if you are concerned about tumor "take" or are working with a particularly challenging cell line (e.g. PDX lines), then you may want to consider a "super-immunodeficient" model that lacks NK cells through ablation of IL2r-gamma.
More specifically, I'm referring to models like Taconic's NOG mice and Jax's NSG mice (there are other similar models too), which tend to be the most permissive models for human tissue and cell engraftment. Rag(-/-)/IL2rg(-/-) models are also available. I know we have one at Taconic (model #4111) and I believe one is available through Jax too.