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.