Linaclotide in Treating Patients With Stages 0-3 Colorectal Cancer

PRIMARY OBJECTIVES: I. To determine whether, compared to placebo, linaclotide administered as a single oral daily dose x 7 days, induces a pharmacodynamics (PD) effect on cGMP levels, based on biopsy samples of adenomas or resected colorectal adenocarcinomas. SECONDARY OBJECTIVES: I. To compare Ki-67, guanylin levels and GUCY2C expression in adenomas and cancers versus normal tissue after exposure to linaclotide or placebo. II. To confirm the safety and tolerability of linaclotide in sporadic adenoma and cancer patients. TRANSLATIONAL OBJECTIVE: I. To assess the pharmacodynamic effect of linaclotide on pathway-specific biomarkers relevant to GUCY2C signaling (i.e. VASP phosphorylation), markers of mutant APC-beta-catenin signaling (beta-catenin levels, beta-catenin nuclear localization, axin levels, c-Myc levels, guanylin levels, PCNA expression), based on adenoma/cancer and normal mucosa biopsy samples obtained by endoscopy following linaclotide or placebo exposure. OUTLINE: Patients are randomized to 1 of 2 arms. ARM I: Patients receive linaclotide orally (PO) daily on days 1-7 and undergo standard of care colonoscopy or surgery on day 7. ARM II. Patients receive placebo PO QD on days 1-7 and undergo standard of care colonoscopy or surgery on day 7. After completion of study treatment, patients are followed up at day 14.