The study implies a 2 step study design. Patients are enrolled into 3 separate groups for melanoma, breast, and non-small cell lung cancer. In the first step, 21 patients per disease group are enrolled. If >=2 objective responses (SD, PR, or CR) out of 21 evaluable patients are observed, enrollment continues for other 45 patients as a whole, where response will be positively evaluated if >=10 patients will respond. If <2 objective responses out of 21 evaluable patients per disease group are observed, this(ese) group(s) will no longer be treated with temozolomide.