Patients receiving any medications or substances that are inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible; investigator can change to a similar agent that is a non-CYPA inhibitor/inducer with a washout period of week Patients receiving any medications or substances that are potent inhibitors or inducers of cytochrome P family , subfamily A, polypeptide (CYPA) isoenzymes within days of randomization for list of CYPA inhibitors and inducers Participants receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible; dihydropyridine calcium-channel blockers are permitted for management of hypertension PHASE I AND II SCLC AND UROTHELIAL CARCINOMA EXPANSION COHORT: Patients receiving any medications or substances that are strong and moderate inhibitors or inducers of cytochrome P, family , subfamily A (CYPA) are ineligible Patients receiving any medications or substances that are strong inhibitors of cytochrome (CY)P family subfamily A polypeptide (A) isoenzyme Participants receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible; strong inhibitors and inducers of UGT/PgP should be used with caution Patients taking any medications or substances that are inhibitors or inducers of cytochrome P, family , subfamily A (CYPA) TREATMENT: Eligibility of subjects receiving any medications or substances known to affect or with the potential to affect the activity or pharmacokinetics (i.e., cytochrome P, family , subfamily A, polypeptide [CYP], P-glycoprotein [PgP]) of any of the study drugs will be determined following review of their cases by the principal investigator (PI); patients on strong and moderate cytochrome P system inducers or inhibitors are ineligible; every effort would be made to switch patients off medications that are known substrates of CYP; if it is medically important for the patient to remain on such medications, these patients can still be eligible to participate based on PI discretion Patients receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) Patients receiving any medications or substances that are strong inhibitors or inducers of cytochrome P family , subfamily A, polypeptide (CYPA) isoenzymes should be ineligible Patients receiving any medications or substances that are inhibitors or inducers of cytochrome P family , subfamily C, polypeptide (CYPC) are ineligible (e.g. gemfibrozil, rifampin, trimethoprim, pioglitazone) Patients must NOT be taking current medications or substances that are inhibitors or inducers of cytochrome P family , subfamily A, polypeptide (CYPA) Because MK- is metabolized primarily by the cytochrome P, family , subfamily A, polypeptide (CYPA) liver enzyme, the eligibility of patients taking medications that are potent inducers or inhibitors of that enzyme will be determined following a review of their case by the principal investigator; every effort should be made to switch patients taking such agents or substances to other medications Not receiving any medications or substances that are strong inhibitors of cytochrome P family , subfamily D, polypeptide (CYPD) Participants receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A (CYPA) isoenzymes are ineligible Participants receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) or moderate inhibitors of CYPA are ineligible; dihydropyridine calcium-channel blockers are permitted for management of hypertension Patients requiring any medications or substances that are strong or moderate cytochrome P, family , subfamily A (CYPA) inhibitors or clinically significant enzyme inducers of CYPA are ineligible The eligibility of patients taking medications that are potent inducers or inhibitors of the cytochrome P, family , subfamily A, polypeptide (CYPA) liver enzyme will be determined following a review of their case by the principal investigator; every effort should be made to switch patients taking such agents or substances to other medications; any identified agent needs to be stopped at least weeks prior to study registration Patients receiving any medications or substances that are inhibitors or inducers of cytochrome P family , subfamily A, polypeptide (CYP A) are ineligible PHASE I: Participants receiving any medications or substances that are strong inhibitors of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible Participants receiving any medications or substances that are strong inhibitors or inducers of cytochrome P family , subfamily A, polypeptide (CYPA) isoenzymes are ineligible Patients receiving any medications or substances that are strong inhibitors or strong inducers of cytochrome P, family , subfamily A, polypeptide / (CYPA/) are ineligible Patients receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A (CYPA) or cytochrome P family , subfamily C, polypeptide (CYPC) are ineligible\r\n* For patients on intermediate inducers or inhibitors, attempts should be made to switch to an alternative agent or delay enrollment until treatment course with concomitant agent completed; if not possible, patient may be enrolled if it is felt to be in the patients best interest as decided by the investigator\r\n* Weak inhibitors of CYPA or CYPC should be used with caution and attempts made to limit their use or find alternative agents, if possible Patients receiving any medications or substances that are strong inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible; moderate inducers of CYPA should be used with caution Patients receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) complex are ineligible Patients receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible; an exception will be made for patients who are on ritonavir-based highly active antiretroviral therapy, in which case the starting dose of sunitinib will be modified; every effort should be made to switch patients taking such agents or substances to other medications Individuals receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) enzyme(s) are eligible only if principal investigator approves subject enrollment prior to registration; participants who have received a medication or substance listed may be enrolled on study as long as they have discontinued its use at least hours prior to registration Participants receiving any medications or substances that are strong/intermediate inhibitors or inducers of cytochrome P (CYP) cytochrome P, family , subfamily A, polypeptide (CYPA) or cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible Participants receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible; dihydropyridine calcium-channel blockers are permitted for management of hypertension Patients receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) or cytochrome P, family , subfamily C, polypeptide (CYPC) are ineligible Receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYP A); \r\n* NOTE: oxidative metabolism of MK- in human liver microsomes is catalyzed primarily by CYPA, although direct glucuronidation also occurs; at least days washout period is required in patients who were previously taking strong inhibitors or inducers of CYP. A; patients who are currently taking moderate inhibitors or inducers of CYP A are encouraged to switch to other medications that do not interact with CYP A Participants receiving any medications or substances that are strong inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) are ineligible Patients receiving any medications or substances that are inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYP A) are ineligible Patients who require concurrent treatment with any medications or substances that are potent inhibitors or inducers of cytochrome P, family , subfamily A, polypeptide (CYPA) Taking any of the following agents:\r\n* Chronic treatment with systemic steroids or another immunosuppressive agent\r\n* Live vaccines \r\n* Drugs or substances known to be inhibitors or inducers of the isoenzyme cytochrome P family , subfamily A (CYPA) Receiving any medications or substances that are strong inhibitors of cytochrome P, family , subfamily A, polypeptide / (CYPA/) Refusal or inability to discontinue medications or other substances (eg, foods or dietary supplements) that may affect F SKI- metabolism; notably, as dasatinib metabolism is cytochrome P, family , subfamily A, polypeptide (CYPA)-dependent, the metabolism of F SKI- may be altered by inhibitors and inducers of cytochrome P isoenzyme CYPA; the acceptability of medications and other substances used by the patient will be determined by the study investigators