AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC. METHODS: FAP expression was examined in 134 ...AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC. METHODS: FAP expression was examined in 134 PDAC specimens by immunohistochemistry, and in four pancreatic cancer cell lines (SW1990, Miapaca-2, AsPC-1 and BxPC-3) by Western blotting assay. We also analyzed the association between FAP expression in PDAC cells and the clinicopathology of PDAC patients. RESULTS: The results showed that the FAP was expressed in both stromal fibroblast cells (98/134, 73.1%) and carcinoma cells (102/134, 76.1%). All 4 pancreatic cancer cell lines expressed FAP protein at different levels. Protein bands corresponding to the proteolytically active 170-kDa seprase dimer and its88-kDa seprase subunit were identif ied. Higher FAP expression in carcinoma cells was associated with tumor size (P < 0.001), fi brotic focus (P = 0.003), perineural invasion (P = 0.009) and worse clinical outcome (P = 0.0085). CONCLUSION: FAP is highly expressed in carcinoma cells and f ibroblasts in PDAC tissues, and its expression is associated with desmoplasia and worse prognosis.展开更多
Pancreatic ductal adenocarcinoma(PDA)is among the deadliest cancers in the United States and in the world.Late diagnosis,early metastasis and lack of effective therapy are among the reasons why only 6%of patients diag...Pancreatic ductal adenocarcinoma(PDA)is among the deadliest cancers in the United States and in the world.Late diagnosis,early metastasis and lack of effective therapy are among the reasons why only 6%of patients diagnosed with PDA survive past 5 years.Despite development of targeted therapy against other cancers,little progression has been made in the treatment of PDA.Therefore,there is an urgent need for the development of new treatments.However,in order to proceed with treatments,the complicated biology of PDA needs to be understood first.Interestingly,majority of the tumor volume is not made of malignant epithelial cells but of stroma.In recent years,it has become evident that there is an important interaction between the stromal compartment and the less prevalent malignant cells,leading to cancer progression.The stroma not only serves as a growth promoting source of signals but it is also a physical barrier to drug delivery.Understanding the tumor-stroma signaling leading to development of desmoplastic reaction and tumor progression can lead to the development of therapies to decrease stromal activity and improve drug delivery.In this review,we focus on how the current understanding of biology of the pancreatic tumor microenvironment can be translated into the development of targeted therapy.展开更多
In recent years,fibroblast activation protein(FAP)has emerged as an attractive target for the diagnosis and radiotherapy of cancers using FAP-specific radioligands.Herein,we aimed to design a novel^(18)Flabeled FAP tr...In recent years,fibroblast activation protein(FAP)has emerged as an attractive target for the diagnosis and radiotherapy of cancers using FAP-specific radioligands.Herein,we aimed to design a novel^(18)Flabeled FAP tracer([^(18)F]Al F-P-FAPI)for FAP imaging and evaluated its potential for clinical application.The[^(18)F]Al F-P-FAPI novel tracer was prepared in an automated manner within 42 min with a non-decay corrected radiochemical yield of 32±6%(n=8).Among A549-FAP cells,[^(18)F]Al F-P-FAPI demonstrated specific uptake,rapid internalization,and low cellular efflux.Compared to the patent tracer[^(18)F]FAPI-42,[^(18)F]Al F-P-FAPI exhibited lower levels of cellular efflux in the A549-FAP cells and higher stability in vivo.Micro-PET imaging in the A549-FAP tumor model indicated higher specific tumor uptake of[^(18)F]Al F-P-FAPI(7.0±1.0%ID/g)compared to patent tracers[^(18)F]FAPI-42(3.2±0.6%ID/g)and[68 Ga]Ga-FAPI-04(2.7±0.5%ID/g).Furthermore,in an initial diagnostic application in a patient with nasopharyngeal cancer,[^(18)F]Al F-P-FAPI and[^(18)F]FDG PET/CT showed comparable results for both primary tumors and lymph node metastases.These results suggest that[^(18)F]Al F-P-FAPI can be conveniently prepared,with promising characteristics in the preclinical evaluation.The feasibility of FAP imaging was demonstrated using PET studies.展开更多
Objective Fibroblast activation protein(FAP)has been widely studied and exploited for its clinical applications.One of the difficulties in interpreting reports of FAP-targeted theranostics is due to the lack of accura...Objective Fibroblast activation protein(FAP)has been widely studied and exploited for its clinical applications.One of the difficulties in interpreting reports of FAP-targeted theranostics is due to the lack of accurate controls,making the results less specific and less confirmative.This study aimed to establish a pair of cell lines,in which one highly expresses FAP(HT1080-hFAP)and the other has no detectable FAP(HT1080-vec)as control,to accurately evaluate the specificity of the FAP-targeted theranostics in vitro and in vivo.Methods The cell lines of the experimental group(HT1080-hFAP)and no-load group(HT1080-vec)were obtained by molecular construction of the recombinant plasmid pIRES-hFAP.The expression of hFAP in HT1080 cells was detected by PCR,Western blotting and flow cytometry.CCK-8,Matrigel transwell invasion assay,scratch test,flow cytometry and immunofluorescence were used to verify the physiological function of FAP.The activities of human dipeptidyl peptidase(DPP)and human endopeptidase(EP)were detected by ELISA in HT1080-hFAP cells.PET imaging was performed in bilateral tumor-bearing nude mice models to evaluate the specificity of FAP.Results RT-PCR and Western blotting demonstrated the mRNA and protein expression of hFAP in HT1080-hFAP cells but not in HT1080-vec cells.Flow cytometry confirmed that nearly 95%of the HT1080-hFAP cells were FAP positive.The engineered hFAP on HT1080 cells had its ability to retain enzymatic activities and a variety of biological functions,including internalization,proliferation-,migration-,and invasion-promoting activities.The HT1080-hFAP xenografted tumors in nude mice bound and took up^(68)GA-FAPI-04 with superior selectivity.High image contrast and tumor-organ ratio were obtained by PET imaging.The HT1080-hFAP tumor retained the radiotracer for at least 60 min.Conclusion This pair of HT1080 cell lines was successfully established,making it feasible for accurate evaluation and visualization of therapeutic and diagnostic agents targeting the hFAP.展开更多
基金Supported by The National Key Project of Scientific and Technical Supporting Programs of China, No. 2006BAI02A14National Natural Science Foundation of China, No. 30770996 and No. 81172310
文摘AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC. METHODS: FAP expression was examined in 134 PDAC specimens by immunohistochemistry, and in four pancreatic cancer cell lines (SW1990, Miapaca-2, AsPC-1 and BxPC-3) by Western blotting assay. We also analyzed the association between FAP expression in PDAC cells and the clinicopathology of PDAC patients. RESULTS: The results showed that the FAP was expressed in both stromal fibroblast cells (98/134, 73.1%) and carcinoma cells (102/134, 76.1%). All 4 pancreatic cancer cell lines expressed FAP protein at different levels. Protein bands corresponding to the proteolytically active 170-kDa seprase dimer and its88-kDa seprase subunit were identif ied. Higher FAP expression in carcinoma cells was associated with tumor size (P < 0.001), fi brotic focus (P = 0.003), perineural invasion (P = 0.009) and worse clinical outcome (P = 0.0085). CONCLUSION: FAP is highly expressed in carcinoma cells and f ibroblasts in PDAC tissues, and its expression is associated with desmoplasia and worse prognosis.
基金Supported by NIH R01 CA169702-01A1(to Zheng L)NIH K23 CA148964-01(to Zheng L)+6 种基金Johns Hopkins School of Medicine Clinical Scientist Award(to Zheng L)Viragh Foundation and the Skip Viragh Pancreatic Cancer Center at Johns Hopkins(to Zheng L)The National Pancreas Foundation(to Zheng L)Lefkofsky Family Foundation(to Zheng L)the NCI SPORE in Gastrointestinal Cancers P50 CA062924(to Zheng L)Lustgarten Foundation(to Zheng L)the Sol Goldman Pancreatic Cancer Center grants(to Zheng L)
文摘Pancreatic ductal adenocarcinoma(PDA)is among the deadliest cancers in the United States and in the world.Late diagnosis,early metastasis and lack of effective therapy are among the reasons why only 6%of patients diagnosed with PDA survive past 5 years.Despite development of targeted therapy against other cancers,little progression has been made in the treatment of PDA.Therefore,there is an urgent need for the development of new treatments.However,in order to proceed with treatments,the complicated biology of PDA needs to be understood first.Interestingly,majority of the tumor volume is not made of malignant epithelial cells but of stroma.In recent years,it has become evident that there is an important interaction between the stromal compartment and the less prevalent malignant cells,leading to cancer progression.The stroma not only serves as a growth promoting source of signals but it is also a physical barrier to drug delivery.Understanding the tumor-stroma signaling leading to development of desmoplastic reaction and tumor progression can lead to the development of therapies to decrease stromal activity and improve drug delivery.In this review,we focus on how the current understanding of biology of the pancreatic tumor microenvironment can be translated into the development of targeted therapy.
基金supported by the National Natural Science Foundation of China(81701729,91949121)Guangdong Basic and Applied Basic Research Foundation(2021A1515011099,China)+1 种基金Outstanding Youths Development Scheme of Nanfang Hospital,Southern Medical University(2017J010,China)Nanfang Hospital Talent Introduction Foundation of Southern Medical University(123456,China)。
文摘In recent years,fibroblast activation protein(FAP)has emerged as an attractive target for the diagnosis and radiotherapy of cancers using FAP-specific radioligands.Herein,we aimed to design a novel^(18)Flabeled FAP tracer([^(18)F]Al F-P-FAPI)for FAP imaging and evaluated its potential for clinical application.The[^(18)F]Al F-P-FAPI novel tracer was prepared in an automated manner within 42 min with a non-decay corrected radiochemical yield of 32±6%(n=8).Among A549-FAP cells,[^(18)F]Al F-P-FAPI demonstrated specific uptake,rapid internalization,and low cellular efflux.Compared to the patent tracer[^(18)F]FAPI-42,[^(18)F]Al F-P-FAPI exhibited lower levels of cellular efflux in the A549-FAP cells and higher stability in vivo.Micro-PET imaging in the A549-FAP tumor model indicated higher specific tumor uptake of[^(18)F]Al F-P-FAPI(7.0±1.0%ID/g)compared to patent tracers[^(18)F]FAPI-42(3.2±0.6%ID/g)and[68 Ga]Ga-FAPI-04(2.7±0.5%ID/g).Furthermore,in an initial diagnostic application in a patient with nasopharyngeal cancer,[^(18)F]Al F-P-FAPI and[^(18)F]FDG PET/CT showed comparable results for both primary tumors and lymph node metastases.These results suggest that[^(18)F]Al F-P-FAPI can be conveniently prepared,with promising characteristics in the preclinical evaluation.The feasibility of FAP imaging was demonstrated using PET studies.
基金This work was supported by the National Natural Science Foundation of China(No.82171986).
文摘Objective Fibroblast activation protein(FAP)has been widely studied and exploited for its clinical applications.One of the difficulties in interpreting reports of FAP-targeted theranostics is due to the lack of accurate controls,making the results less specific and less confirmative.This study aimed to establish a pair of cell lines,in which one highly expresses FAP(HT1080-hFAP)and the other has no detectable FAP(HT1080-vec)as control,to accurately evaluate the specificity of the FAP-targeted theranostics in vitro and in vivo.Methods The cell lines of the experimental group(HT1080-hFAP)and no-load group(HT1080-vec)were obtained by molecular construction of the recombinant plasmid pIRES-hFAP.The expression of hFAP in HT1080 cells was detected by PCR,Western blotting and flow cytometry.CCK-8,Matrigel transwell invasion assay,scratch test,flow cytometry and immunofluorescence were used to verify the physiological function of FAP.The activities of human dipeptidyl peptidase(DPP)and human endopeptidase(EP)were detected by ELISA in HT1080-hFAP cells.PET imaging was performed in bilateral tumor-bearing nude mice models to evaluate the specificity of FAP.Results RT-PCR and Western blotting demonstrated the mRNA and protein expression of hFAP in HT1080-hFAP cells but not in HT1080-vec cells.Flow cytometry confirmed that nearly 95%of the HT1080-hFAP cells were FAP positive.The engineered hFAP on HT1080 cells had its ability to retain enzymatic activities and a variety of biological functions,including internalization,proliferation-,migration-,and invasion-promoting activities.The HT1080-hFAP xenografted tumors in nude mice bound and took up^(68)GA-FAPI-04 with superior selectivity.High image contrast and tumor-organ ratio were obtained by PET imaging.The HT1080-hFAP tumor retained the radiotracer for at least 60 min.Conclusion This pair of HT1080 cell lines was successfully established,making it feasible for accurate evaluation and visualization of therapeutic and diagnostic agents targeting the hFAP.
