ABSTRACT
Objective To explore the expression characteristics of vascular endothelial growth factor (VEGF) receptor (VEGFR).Methods The 123I-VEGF165 and 123I-VEGF121 were marked to human umbilical vein endothelial cell (HUVEC),several human tumor cell lines (HMC-1,A431,KU812,U937,HEP-1,HEP-G2,HEP-3B and Raji),a variety of human tumors and adjacent non-neoplastic tissues as well as peripheral blood cells.Then,the specific binding site maximal binding capacity (Bmax),dissociation constant (Kd) and concentration of 50％ required specific binding (IC5o) were analyzed.The affinity,quantity and specificity of different cells combined with 123I-VEGF165 and 123I-VEGF121 were judged.Results Two kinds of analogous 123I-VEGF165 binding sites on the surface of HUVEC were found.While,there was only one kind of 123I-VEGF121binding site.123I-VEGF121 was found on the special cell lines (HUVEC,HEP-1 and HMC-1) and special early tumors (early melanoma,ductal breast cancer,ovarian cancer and meningioma).Compared with peripheral blood cells and adjacent non-neoplastic tissues,the number of VEGFR of tumor cells was bigger.Among the 123I-VEGF165 marked VEGFR,the Bmax value of early melanoma,ductal breast cancer,hepatocellular carcinoma,papillary thyroid carcinoma,ovarian carcinoma,renal cell carcinoma were 45 ± 13,13 ± 3,25 ±8,5 ±2,42 ± 12,20 ±6,respectively.While among the 123I-VEGF121 marked VEGFR,the Bmax value of early melanoma,ductal breast cancer,ovarian carcinoma were 30 ± 8,8 ± 3,20 ± 6.123I-VEGF165 and 123I-VEGF121 had specific binding capacity with a variety of human tumor cells and tissues.Compared with 123I-VEGF121,there were more different kinds of tumor cells could be bound to 123I-VEGF165 with higher capacity.Conclusion 123I-VEGF165 may be a potential target of tumor imaging in vivo,and it is expected to be used to diagnose and treat tumors.
ABSTRACT
To clone and sequence the human tissue kallikrein gene of Chinese, and to construct eukaryotic expression recombinant of KK, total RNA was extracted from human pancreas and human tissue kallikrein gene cDNA was amplified by PCR after reverse-transcription by using Oligo(dT)primer. The original kallikrein cDNA was recovered and filled with Klenow enzyme and inserted into KS plasmid. After restriction endonuclease digestion, KK cDNA was sequenced by ABI 377 analyzer.Then the KKgene was amplified from pBluescript KSKK and inserted into pcDNA3. A sequence comparison showed that the cloned kallikrein gene was only one nucleotide different from that reported in the Genbank. The coding amino acid was Asp in the Genbank gene, while the coding amino acid of Chinese kallikrein gene was Asn. The KK cDNA fragment was inserted into the eukaryotic expression vector pcDNA3. The cloned kallikrein gene and the pcDNA3KK can be used for further study in gene therapy...
ABSTRACT
To clone and sequence the human tissue kallikrein gene of Chinese, and to construct eukaryotic expression recombinant of KK, total RNA was extracted from human pancreas and human tissue kallikrein gene cDNA was amplified by PCR after reverse-transcription by using Oligo(dT) primer. The original kallikrein cDNA was recovered and filled with Klenow enzyme and inserted into KS plasmid. After restriction endonuclease digestion, KK cDNA was sequenced by ABI377 analyzer. Then the KK gene was amplified from pBluescript KSKK and inserted into pcDNA3. A sequence comparison showed that the cloned kallikrein gene was only one nucleotide different from that reported in the Genbank. The coding amino acid was Asp in the Genbank gene, while the coding amino acid of Chinese kallikrein gene was Asn. The KK cDNA fragment was inserted into the eukaryotic expression vector pcDNA3. The cloned kallikrein gene and the pcDNA3KK can be used for further study in gene therapy.. .