Abstract: The present invention includes biomarkers and methods for predicting recurrence-free survival and determination of risk for colorectal liver metastasis (LM) by determining a level of microsatellite instability at tetranucleotide repeats (EMAST) and at mono- and a dinucleotide repeat loci (MSI-L) or a SMARCA2R-LOH in colorectal cancer (CRC) patients. Results obtained indicate that stage II and III patients with MSI-M had a shorter recurrence-free survival than the rest of patients with high levels of MSI (MSI-H) or with highly stable microsatellites, and that MSI-M is an independent predictor for recurrent distant metastasis in primary stage II and III CRCs. It was found that SMARCA2R-LOH and MSI-M are found in stage IV primary CRC and LM tissues.

Abstract: Methods for treating a patient at risk for or diagnosed with colorectal cancer are disclosed herein. The method of the present invention determines the overall expression of MSH3 in cells suspected of being colorectal cancer cells from the patient and predicting the efficacy of therapy with a genotoxic anti-neoplastic agent for treating the patient, wherein a decrease in the overall expression of MSH3 in the patient cells when compared to the expression of MSH3 in normal colorectal cells indicates a predisposition to responsiveness to genotoxic anti-neoplastic agent therapy, wherein the therapy comprises administering an effective amount of the genotoxic anti-neoplastic agent therapy to patients.

Abstract: Superfragments of chromosomal DNA having 1 million to 100 million base pairs may be formed by irradiating microcells containing a chromosome with a high dose of .gamma.-irradiation. Such superfragments are useful for the rapid cloning of genes.