Inclusion Criteria:

1. Patients with histologically-confirmed, advanced unresectable solid tumors who have
progressed on (or not been able to tolerate) standard therapy or for whom no standard
anticancer therapy exists.

2. At least one measurable lesion as defined by RECIST criteria for solid tumors.

3. Age ≥ 20

4. Eastern Cooperative Oncology Group Performance Status (ECOG P.S.) of ≤ 2

5. Life expectancy of ≥ 12 weeks

6. Patients must have the laboratory values Patients in the expansion part of this study
have to meet the following criteria in addition to the criteria described above.

7. Availability of a representative tumor tissue specimen (either archival tumor or
fresh tumor biopsy) for pre-screening.

8. Patients whose molecular status proved to meet the criteria (PIK3CA
mutation/amplification and/or PTEN mutation and/or low/null PTEN expression) during
pre-screening.

Exclusion Criteria:

1. Patients who have brain metastases or who have signs/symptoms attributable and have
not been assessed with radiologic imaging to rule out the presence of brain
metastases

2. Patients with any peripheral neuropathy ≥ CTCAE grade 2

3. Patients with unresolved diarrhea ≥ CTCAE grade 2

4. Patients with a history of photosensitivity reactions to other drugs

5. Women of child-bearing potential who are pregnant or breast feeding or adults of
reproductive potential not employing an effective method of birth control. Barrier
contraceptives must be used throughout the trial in both sexes. Women of
child-bearing potential, defined as sexually mature women who have not undergone a
hysterectomy or who have not been naturally postmenopausal for at least consecutive 1
years (i.e., who has had menses any time in the preceding consecutive 2 years), must
have a negative serum pregnancy test ≤ 7 days prior to starting BEZ235.

Other protocol-defined inclusion/exclusion criteria may apply