RO4929097 And Exemestane in Treating Pre- and Postmenopausal Patients With Advanced or Metastatic Breast Cancer

Inclusion Criteria: * Diagnosis of breast cancer * Locally advanced or metastatic disease for which curative measures are not effective * Relapsed disease with (or within 6 months of discontinuation of) an adjuvant nonsteroidal aromatase inhibitor or tamoxifen * Progressive disease during treatment with first- or second-line hormonal therapy that could include a nonsteroidal aromatase inhibitor, tamoxifen, or fulvestrant * Recurrent disease * No locally recurrent resectable disease * Histologically confirmed estrogen receptor-positive (ER+) by IHC * Must have ≥ 5% strong staining for ER+ or ≥ 10% weak staining * Measurable disease defined as ≥ 1 lesion that can be accurately measured in ≥ 1 dimension (longest diameter to be recorded) as ≥ 20 mm by conventional techniques OR as ≥ 10 mm by spiral CT scan * No HER2/neu-positive disease * No known brain metastases * Pre- or postmenopausal status * ECOG performance status 0-1 * Life expectancy ≥ 6 months * WBC ≥ 3,500/mm\^3 * ANC ≥ 1,500/mm\^3 * Platelet count ≥ 100,000/mm\^3 * Hemoglobin ≥ 9 g/dL * Total bilirubin ≤ 2 mg/dL * AST and ALT ≤ 2.5 times upper limit of normal * Creatinine normal OR creatinine clearance ≥ 60 mL/min * Able to swallow and retain oral medication * Negative pregnancy test * Not pregnant or nursing * Fertile patients must use effective contraception during and for ≥ 12 months after completion of study therapy * More than 5 years since other invasive cancer except basal or squamous cell cancer of the skin or cervical carcinoma in situ * No history of allergic reactions attributed to compounds of similar chemical or biologic composition to gamma-secretase inhibitor RO4929097 or other agents used in the study * No history of torsades de pointes * No malabsorption syndrome or other condition that would interfere with intestinal absorption (e.g., ulcerative colitis) * Not serologically positive for hepatitis B or C, have a history of liver disease, other forms of hepatitis, or cirrhosis * No uncontrolled hypocalcemia, hypomagnesemia, hyponatremia, hypophosphatemia, or hypokalemia * No uncontrolled intercurrent illness including, but not limited to, any of the following: * Ongoing or active infection requiring parenteral antibiotics * Impairment of lung function (e.g., chronic obstructive pulmonary disease or lung conditions requiring oxygen therapy) * Symptomatic congestive heart failure (NYHA class III-IV heart disease) * Unstable angina pectoris, angioplasty, stenting, and or myocardial infarction within the past 6 months * Uncontrolled hypertension (systolic BP \> 180 mm Hg or diastolic BP \> 100 mm Hg on 2 consecutive measurements separated by a 1-week period) despite adequate medical support * Clinically significant cardiac arrhythmia (multifocal premature ventricular contractions, bigeminy, trigeminy, torsades de pointes, ventricular tachycardia that is symptomatic, or requiring treatment) * A requirement for antiarrthymics or other medications known to prolong QTC * Uncontrolled diabetes (hyperosmolar state, ketoacidosis, etc.) * Psychiatric illness and/or social situations that would limit compliance with study requirements * No baseline QTcF \> 450 msec (male) or \> 470 msec (female) * See Disease Characteristics * Fully recovered from all previous adverse events * No prior exemestane for metastatic or recurrent breast cancer, or within the past 6 months in the adjuvant setting * More than 4 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin C) * At least 2 weeks since prior radiotherapy * At least 2 weeks since prior and no other concurrent investigational agents * No prior exposure to γ-secretase inhibitors * No concurrent medications with narrow therapeutic indices that are metabolized by cytochrome P450 (CYP450), including warfarin sodium (Coumadin®) * No other concurrent CYP3A4 substrates, inducers, or inhibitors * No concurrent combination antiretroviral therapy for HIV-positive patients * No other concurrent anticancer agents or therapies, including chemotherapy, radiotherapy, surgery, immunotherapy, hormonal therapy, or biologic therapy * No concurrent medications or food that may interfere with the metabolism of gamma-secretase inhibitor RO4929097, including ketoconazole and grapefruit juice * No concurrent antiarrhythmics or other medications known to prolong QTc