Inclusion Criteria:
1. Age ≥ 18 years and ≤ 75 years, regardless of gender;
2. Advanced solid tumors with clear pathological confirmation, including but not limited to gastric cancer, colorectal cancer, pancreatic cancer, prostate cancer, etc.; at least one measurable lesion meeting RECIST 1.1 criteria (according to RECIST 1.1, the longest diameter of a measurable lesion on spiral CT scan ≥ 10 mm, or the short diameter of a pathological lymph node ≥ 15 mm);
3. Tumor tissue positive for Claudin 18.2, GCC, TROP2, or PSMA targets by immunohistochemistry (IHC) (expression intensity ≥ 2+; percentage of positive cells ≥ 40%);
4. Meets the indications for PBMC collection and has no contraindications for cell collection;
5. Failure of standard second-line treatment, or lack of a standard treatment regimen; or refusal to receive chemotherapy (with signed documentation);
6. ECOG performance status: 0-1;
7. Life expectancy: ≥ 3 months;
8. Toxicities from prior chemotherapy or other anti-tumor therapies must have resolved after a washout period (except for residual alopecia), ensuring that all organ functions meet the inclusion criteria;
9. Adequate organ function, including:
1. Adequate immune function: absolute lymphocyte count (ALC) ≥ 0.5 × 10⁹/L, absolute neutrophil count (ANC) ≥ 1.0 × 10⁹/L, monocyte count ≥ 0.1 × 10⁹/L.
2. Adequate hematopoietic function: platelet count ≥ 75 × 10⁹/L, hemoglobin ≥ 90 g/L. Patients must not have received blood transfusions or treatments such as granulocyte colony-stimulating factor, thrombopoietin, or erythropoietin within 14 days prior to the blood count assessment.
3. Adequate liver function: total bilirubin (TBIL) \< 2 × upper limit of normal (ULN), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) \< 2.5 × ULN.
4. Adequate renal function: creatinine (Cr) ≤ 1.5 × ULN.
5. Adequate coagulation function: prothrombin time (PT) or activated partial thromboplastin time (APTT) \< 1.5 × ULN, and international normalized ratio (INR) \< 1.5.
10. Individuals of childbearing potential must agree to use effective contraception during the study;
11. Ability to understand and willingness to sign a written informed consent form;
12. Willingness and ability to comply with scheduled visits, treatment plans, laboratory tests, and other study procedures.
Exclusion Criteria:
1. Oncological emergencies requiring immediate intervention, such as malignant pericardial effusion or tamponade, superior vena cava syndrome, or spinal cord compression;
2. Significant cardiovascular disease, including:
1. Documented major cardiovascular events within the past 6 months, such as myocardial infarction, angina pectoris, heart failure, severe arrhythmia, or prior angioplasty, stent implantation, or coronary artery bypass grafting;
2. Clinically significant QT interval prolongation (QTcF \> 470 ms for women or QTcF \> 450 ms for men);
3. Clinically significant bleeding tendency or coagulation disorders (e.g., hemophilia);
4. Active infection with HIV, syphilis, hepatitis B virus (HBV), or hepatitis C virus (HCV);
5. History of involuntary commitment due to mental illness, or any psychiatric condition deemed by the investigator to make the patient unsuitable for the trial;
6. Concurrent autoimmune diseases, or long-term use of immunosuppressants or systemic corticosteroids;
7. Poor compliance, as assessed by the investigator;
8. Prior treatment with any targeted CAR-T cell therapy within 3 months before this CAR-T infusion;
9. Uncontrolled active bacterial or fungal infections;
10. Any other condition that, in the opinion of the investigator, makes the patient ineligible for the study.
