Endostar + GT in Pulmonary Metastases of Soft Tissue Sarcoma

Inclusion Criteria: * Age between 18-70 years, male or female. * ECOG performance status \<=2. * Life expectancy \>= 3 months. * Histologically or cytologically confirmed soft tissue sarcoma (GIST excluded). * Patients must have had a prior anthracycline and/or ifosfamide in either the adjuvant or metastatic setting but not more than one regimen. * At least one measurable pulmonary metastasis tumor lesions according to RECIST 1.1 criteria. * Laboratory values: Hemoglobin (Hb) \>= 90 g/L and no blood transfusion within 14 days, Absolute neutrophil count (ANC) \>= 1.5 x 10\^9/L, Platelet (Plt)\>= 80 x 10\^9/L, Total Bilirubin (Tbil)=\< 1.5 x upper limit of normal (ULN), Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) =\< 2.5 x ULN or =\< 5 x ULN if liver metastases are present, Serum creatinine (Cr) =\< 1.0 x ULN, Endogenous creatinine clearance (Ccr)\> 50 mL/min (Cockcroft-Gault). * Women of child bearing potential must have a negative serum or urine pregnancy test within 7 days before enrollment and be willing to use effective contraception during study and for 8 weeks after last IMP administration. * Willingness to participate in study and sign informed consent form. Exclusion Criteria: * Females who are pregnant or breastfeeding or have Childbearing potential unwilling to use effective contraception. * Prior therapy with Gemcitabine, Docetaxel and Endostar. * Subjects participating in other clinical trials within 4 weeks before enrollment. * Accompanied by rapid progress of organ invasions, e.g.lesion areas are great than one half of liver or lung or have liver dysfunction. * Uncontrolled central nervous system disorder or psychiatric illness. * Current, serious, clinically significant cardiac arrhythmias, symptomatic congestive heart failure, myocardial infarction before enrollment. * Patients with abnormal bone marrow function: ANC \< 1.5 x 10\^9/L, Plt \< 75 x 10\^9/L, Hb \< 90g/L. * Patients with renal dysfunction: Cr \> 1.5 x ULN. * Patients with liver dysfunction: Tbil \> 1.5 x ULN. * Uncontrolled brain metastases. * Unwillingness or inability to comply with the study protocol.