Obatoclax Mesylate and Topotecan Hydrochloride in Treating Patients With Relapsed or Refractory Small Cell Lung Cancer or Advanced Solid Tumors

Inclusion Criteria: * Histologically or cytologically confirmed diagnosis of 1 of the following: * Advanced solid tumor (phase I) * Topotecan hydrochloride must be an appropriate treatment for this cancer * Small cell lung cancer (SCLC) (phase II) * Progressed after one prior platinum-based chemotherapy regimen * Pathology materials (tumor tissue) will be used for correlative studies, if available * No progressive brain metastases * Treated brain metastases allowed provided patient is neurologically stable and does not require steroids * No leptomeningeal involvement * ECOG performance status (PS) 0-1 OR Karnofsky PS 70-100% * Leukocytes ≥ 3,000/mcL * Absolute neutrophil count ≥ 1,500/mcL * Platelet count ≥ 100,000/mcL * Total bilirubin normal * AST and ALT ≤ 2.5 times upper limit of normal * Creatinine normal OR creatinine clearance ≥ 60 mL/min * Not pregnant or nursing * Fertile patients must use effective double barrier method of contraception during and for 3 months after completion of study therapy * At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin C) and recovered * At least 4 weeks since prior radiotherapy and recovered * No concurrent combination antiretroviral therapy for HIV-positive patients * No other concurrent investigational agents or anticancer therapy Exclusion Criteria: * History of allergic reactions attributed to compounds of similar chemical or biological composition to obatoclax mesylate or topotecan hydrochloride (e.g., irinotecan) * Concurrent uncontrolled illness including, but not limited to, any of the following: * Ongoing or active infection * Symptomatic congestive heart failure * Unstable angina pectoris * Cardiac arrhythmia * Psychiatric illness or social situations that would limit compliance with study requirements * History of seizure disorder or other neurological dysfunction (except peripheral neuropathy)