Metastatic colorectal cancer (mCRC) is a clinical and molecular heterogeneous disease. Currently, for mCRC, extended rat sarcoma (RAS) testing is recommended in routine clinical practice before any treatment. RAS mutational status is significantly associated with the outcome of patients and strongly predictive for anti-EGFR-targeted therapy. However, specific treatments for RAS target are not yet available. Previous studies have shown that direct inhibition of RAS proteins has limited clinical benefits. Recently, a promising drug, AMG-510, which can directly inhibit KRAS G12C has been reported; however, it needs further confirmation. In the past few years, important advances have also been made in approaches designed to indirectly target RAS by inhibiting RAS effectors, multi-target combination strategies and immunotherapy. They are expected to be effective treatments for RAS target. This article summarizes the precision treatment of RAS-mutant mCRC.

Objective To explore the preparation of specific immune RMA(iRNA) on anti-rabies and further study immunotherapy of rabies virus exposure. Methods Horses were immunized with the rabi-es virus and their livers were isolated from the horse of antiserum, from which total RNA was extracted and purified by sodium lauryisulfonate, phenol, chloroform, ethyiene glycol monomethyl ether, cetyltrimethyam-moniumbromide and alcohol. Results Pure preparation physico-chemical characterization was analyzed, and it's weight was 0.15% of weight of liver. The RNA contained 2.86% DNA and 1.16% protein. The iRNA with a maximum UV absorbance at 258 nm and A_(258/280) about 2.0. The test of RNA was positive, which had a relative molecular mas of 13.7×10~3 by high performance liquid chromatography(HPLC), and its hy-perchromic effect was 50.67%. The vesults of biological activity was showed that the rate of leucocyte adher-ence inhibition(LAI) was 41.73%, The protective rate was 50% and prolonging the life was 31.62%. Conclusion The results obtained with the practical value were identical and provide a basis on medicines of anti-rabies.