Fibroblast activation protein-based theranostics in pancreatic cancer.

Fibroblast activation protein-α (FAP) is a type II transmembrane serine protease that has specific endopeptidase activity. Given its well-established selective expression in the activated stromal fibroblasts of epithelial cancers, although not in quiescent fibroblasts, FAP has received substantial research attention as a diagnostic marker and therapeutic target. Pancreatic cancer is characterized by an abundant fibrotic or desmoplastic stroma, leading to rapid progression, therapeutic resistance, and poor clinical outcomes. Numerous studies have revealed that the abundant expression of FAP in cancer cells, circulating tumor cells, stromal cells, and cancer-associated fibroblasts (CAFs) of pancreatic adenocarcinoma is implicated in diverse cancer-related signaling pathways, contributing to cancer progression, invasion, migration, metastasis, immunosuppression, and resistance to treatment. In this article, we aim to systematically review the recent advances in research on FAP in pancreatic adenocarcinoma, including its utility as a diagnostic marker, therapeutic potential, and correlation with prognosis. We also describe the functional role of FAP-overexpressing stromal cells, particulary CAFs, in tumor immuno- and metabolic microenvironments, and summarize the mechanisms underlying the contribution of FAP-overexpressing CAFs in pancreatic cancer progression and treatment resistance. Furthermore, we discuss whether targeting FAP-overexpressing CAFs could represent a potential therapeutic strategy and describe the development of FAP-targeted probes for diagnostic imaging. Finally, we assess the emerging basic and clinical studies regarding the bench-to-bedside translation of FAP in pancreatic cancer.

18F-FDG PET/CT for the early prediction of the response rate and survival of patients with recurrent or metastatic breast cancer.

The present study aimed to explore the value of fludeoxyglucose F 18 positron emission tomography-computed tomography (PET/CT) for the early prediction of chemotherapy remission rates and survival in patients with recurrent and metastatic breast cancer. A total of 24 patients diagnosed with recurrent or metastatic breast cancer between 2009 and 2014 were enrolled. All patients underwent a PET/CT examination prior to (PET/CT1) and following (PET/CT2) chemotherapy. Differences of PET/CT1 maximal standardized uptake values (SUVmax), PET/CT2 SUVmax, ΔSUVmax and the ΔSUVmax% between objective remission (OR) and non-OR groups were measured. Survival differences between OR and non-OR groups and the overall survival (OS) between metabolic responsive and metabolic non-responsive groups were analyzed. In the present study, it was revealed that ΔSUVmax and ΔSUVmax% were significantly higher in the OR group compared with the non-OR group (P<0.001). Overall survival was significantly prolonged in the OR and metabolic responder groups compared with their respective control groups (P<0.001 and P<0.01, respectively). ΔSUVmax% were significantly positively associated with OS (r2=0.266; P<0.01). In conclusion, PET/CT may be valuable for the early prediction of the chemotherapy efficacy and survival of patients with recurrent or metastatic breast cancer.

Intra-individual comparison of therapeutic responses to vascular disrupting agent CA4P between rodent primary and secondary liver cancers.

AIM: To compare therapeutic responses of a vascular-disrupting-agent, combretastatin-A4-phosphate (CA4P), among hepatocellular carcinomas (HCCs) and implanted rhabdomyosarcoma (R1) in the same rats by magnetic-resonance-imaging (MRI), microangiography and histopathology. METHODS: Thirty-six HCCs were created by diethylnitrosamine gavage in 14 rats that were also intrahepatically implanted with one R1 per rat as monitored by T2-/T1-weighted images (T2WI/T1WI) on a 3.0T clinical MRI-scanner. Vascular response and tumoral necrosis were detected by dynamic contrast-enhanced (DCE-) and CE-MRI before, 1 h after and 12 h after CA4P iv at 10 mg/kg (treatment group n = 7) or phosphate-buffered saline at 1.0 mL/kg (control group n = 7). Tumor blood supply was calculated by a semiquantitative DCE parameter of area under the time signal intensity curve (AUC30). In vivo MRI findings were verified by postmortem techniques. RESULTS: On CE-T1WIs, unlike the negative response in all tumors of control animals, in treatment group CA4P caused rapid extensive vascular shutdown in all R1-tumors, but mildly or spottily in HCCs at 1 h. Consequently, tumor necrosis occurred massively in R1-tumors but patchily in HCCs at 12 h. AUC30 revealed vascular closure (66%) in R1-tumors at 1 h (P < 0.05), followed by further perfusion decrease at 12 h (P < 0.01), while less significant vascular clogging occurred in HCCs. Histomorphologically, CA4P induced more extensive necrosis in R1-tumors (92.6%) than in HCCs (50.2%) (P < 0.01); tumor vascularity heterogeneously scored +~+++ in HCCs but homogeneously scored ++ in R1-tumors. CONCLUSION: This study suggests superior performance of CA4P in metastatic over primary liver cancers, which could guide future clinical applications of vascular-disrupting-agents.​.

Analysis of long non-coding RNA expression profiles in clear cell renal cell carcinoma.

To investigate the expression patterns of long non-coding RNAs (lncRNAs) in clear cell renal cell carcinoma (ccRCC) and in metastatic renal cell carcinoma (RCC), the present study downloaded three human exon arrays available from the public Gene Expression Omnibus. The probes of the human exon arrays were re-annotated and the probes uniquely mapping to lncRNAs were retained at the gene level. Following the analysis of GSE53757 and GSE46699, which contained paired ccRCC cancer and normal adjacent tissue samples, 32 differentially expressed lncRNAs (adjusted P<0.01) in ccRCC were identified. Various lncRNAs, including ENSG00000177133, NR_024418, T-cell leukemia/lymphoma 6 (TCL6), growth arrest-specific transcript 5, deleted in lymphocytic leukemia 2, colorectal neoplasia differentially expressed (CRNDE) and MIR155HG, have been reported to be abnormally expressed in cancers. Of these genes, NR_24418 and TCL6 have been reported to be associated with ccRCC. Following analysis of GSE47352, which contained 4 primary metastatic and 5 non-metastatic tumor samples, the 50 top differentially expressed lncRNAs were identified in metastatic ccRCC (Mann-Whitney U test, P<0.05). Comparison with the ccRCC associated lncRNAs revealed that the lncRNA CRNDE demonstrated an increased expression in ccRCC and metastatic ccRCC samples, which suggested that CRNDE is important in the progression of ccRCC. The lncRNA ENSG00000244020 was decreased in ccRCC and metastatic ccRCC, suggesting that silencing of ENSG00000244020 may be important in ccRCC development. Overall, a set of lncRNAs was identified as differentially expressed in ccRCC and metastatic ccRCC, providing potential candidates for the discovery of novel cancer biomarkers and therapeutic targets to improve diagnosis and therapy in RCC.

Biometabolic Distribution of 99mTc-3PRGD2 and Its Potential Value in Monitoring Chemotherapeutic Effects.

Previous studies have reported that 99mTc-3PRGD2 is an excellent tumor imaging agent that showed a good correlation with integrin αvß3, a main factor of tumor-induced angiogenesis. In this study, we investigated the biometabolic distribution characteristics of 99mTc-3PRGD2 with a continuous dynamic acquisition mode to explore the potential value of 99mTc-3PRGD2 in monitoring chemotherapeutic effects in VX2 tumor models. Eighteen rabbits with 27 implanted VX2 squamous cell tumors were randomly divided into a nontreated control group (NTG, n = 8; 12 tumors) and a treatment group (TG, n = 10; 15 tumors). 99mTc-3PRGD2 imaging was performed prior to cisplatin injection and repeated on days 0, 1, 7, and 14 postinjection. Continuous dynamic scanning up to 30 minutes; static imaging at 0.5 hours, 1 hour, and 3 hours; and single-photon emission computed tomography/computed tomography (SPECT/CT)-integrated imaging at 3 hours post-99mTc-3PRGD2 injection were performed. The peak time (time to reach peak in dynamic curve), tumor to normal (T/N) ratios, and their change rates relative to pretherapy were calculated. Autoradiography, hematoxylin-eosin (H&E) staining, and CD31 and integrin αv immunohistochemical staining were examined. VX2 tumors were clearly visualized at 3 hours post-99mTc-3PRGD2 injection. Tumors in the TG shrank significantly on day 7 after cisplatin administration (p < .05). The half-life (t1/2) of the radiotracer in heart, liver, and tumor in the NTG were 3.43 ± 0.94 minutes, 13.41 ± 9.17 minutes, and 70.83 ± 33.37 minutes, respectively. The peak time was delayed in the TG immediately and continuously after cisplatin administration compared to the peak time in the NTG. The T/N values and their change rates decreased significantly in the TG compared to the NTG after therapy (p < .05). The immunostained areas were significantly decreased in the TG (p < .05) compared to the NTG. 99mTc-3PRGD2 was an excellent imaging agent for demonstrating tumor angiogenesis. The peak time, T/N values, and their change rates were sensitive parameters to monitor early chemotherapeutic effects. Due to the specific target mechanism and the cost-effective value of 99mTc-3PRGD2, 99mTc-3PRGD2 SPECT imaging may have potential in detecting the therapeutic effects of anticancer therapy.

Electroacupuncture improves survival in rats with lethal endotoxemia via the autonomic nervous system.

BACKGROUND: Recent advances have indicated a complex interplay between the autonomic nervous system and the innate immune system. Targeting neural networks for the treatment of sepsis is being developed as a therapeutic strategy. Because electroacupuncture at select acupoints can modulate activities of the autonomic nervous system, we tested the hypothesis that electroacupuncture at specific acupoints could modulate systemic inflammatory responses and improve survival via its impact on the autonomic nervous system in a rat model of sepsis. METHODS: Sprague-Dawley male rats received electroacupuncture for 45 min before and at 1, 2, or 4 h after a lethal dose of intraperitoneal lipopolysaccharide injection (6 mg/kg). Outcomes included survival and systemic cytokine responses. Also, the possible roles of neural circuitry, including the hypothalamic-pituitary-adrenal axis and the autonomic nervous system, were evaluated. RESULTS: Electroacupuncture pretreatment at the Hegu acupoints significantly attenuate systemic inflammatory responses and improve survival rate from 20% to 80% in rats with lethal endotoxemia. Such a site-specific effect requires the activation of muscarinic receptors in the central nervous system, but not increasing central sympathetic tone. In the periphery synergistic, rather than independent, action of the sympathetic and parasympathetic systems is also necessary. CONCLUSIONS: Electroacupuncture pretreatment has a dramatic survival-enhancing effect in rats with lethal endotoxemia, which involves the activation of efferent neural circuits of the autonomic nervous system (e.g., cholinergic antiinflammatory pathway). This approach could be developed as a prophylactic treatment for sepsis or perioperative conditions related to excessive inflammation.

Decreased hepatic peroxisome proliferator-activated receptor-γ contributes to increased sensitivity to endotoxin in obstructive jaundice.

AIM: To investigate the role of hepatic peroxisome proliferator-activated receptor-γ (PPAR-γ) in increased susceptibility to endotoxin-induced toxicity in rats with bile duct ligation during endotoxemia. METHODS: Male Sprague-Dawley rats were subjected to bile duct ligation (BDL). Sham-operated animals served as controls. DNA binding were determined by polymerase chain reaction, Western blotting analysis, and electrophoretic mobility shift assay, respectively. BDL and sham-operated rats received a non-lethal dose of intraperitoneal lipopolysaccharide (LPS) injection (3 mg/kg, i.p.). Additionally, the potential beneficial effects of the PPAR-γ agonist rosiglitazone were determined in BDL and sham-operated rats treated with a non-lethal dose of LPS. Survival was assessed in BDL rats treated with a non-lethal dose of LPS and in sham-operated rats treated at a lethal dose of LPS (6 mg/kg, i.p.). RESULTS: PPAR-γ activity in rats undergoing BDL was significantly lower than in the sham-controls. Hepatic PPAR-γ gene expression was downregulated at both the mRNA and protein levels. In a parallel group, serum levels of pro-inflammatory cytokines were nearly undetectable in the sham-operated rats. When challenged with a non-lethal dose of LPS (3 mg/kg), the BDL rats had approximately a 2.4-fold increase in serum IL-6, a 2.7 fold increase in serum TNF-α, 2.2-fold increase in serum IL-1 and 4.2-fold increase in serum ALT. The survival rate was significantly lower as compared with that in sham-operated group. Additionally, rosiglitazone significantly reduced the concentration of TNF-α, IL-1ß, IL-6 and ALT in sham-operated rats, but not in BDL rats, in response to LPS (3 mg/kg). Also, the survival was improved by rosiglitazone in sham-operated rats challenged with a lethal dose of LPS, but not in BDL rats, even with a non-lethal dose of LPS (3 mg/kg). CONCLUSION: Obstructive jaundice downregulates hepatic PPAR-γ expression, which in turn may contribute to hypersensitivity towards endotoxin.

18F-FDG PET/CT-related metabolic parameters and their value in early prediction of chemotherapy response in a VX2 tumor model.

OBJECTIVE: This study acquired fluorine-18-deoxyglucose (FDG) kinetic parameters prior and subsequent to cisplatin chemotherapy so as to define the optimal parameters for early prediction of chemotherapy response. METHODS: A total of 12 non-tumor-bearing rabbits were used to obtain noninvasive input function, five VX2 tumor-bearing rabbits were used for validation and 32 tumor-bearing rabbits underwent 4 mg kg(-1) cisplatin chemotherapy. Dynamic FDG PET/CT was performed at pretherapy, Day 0, Day 1, Day 7 and Day 14 after cisplatin administration. With the application of a three-compartment model, influx index (Ki), k1, k2, k3 and k4 were noninvasively obtained. RESULTS: Sensitive (SG) and insensitive groups (ISG) were defined based on their volume on Day 7. k1, Ki, SUVmean, and SUVmax showed significant decreases in SG vs. ISG at Day 0 (P<.076-0.0001). k1 demonstrated sustained (up to Day 7) differences (P<.028-0.0072), and k2, k3 and k4 showed no significant differences at any time point (P>.05). Soon after cisplatin administration, GLUT-1 expression was greatly decreased in SG vs. ISG. CONCLUSIONS: The parameters of SUVmax, SUVmean, Ki and k1 were valuable for the early prediction of chemotherapy response. k1 had a wider observation window compared to SUVmean, SUVmax and Ki, and k1 also reflected the changes in GLUT-1 expression.

[The modulation of 4-aminopyridine sensitive potassium channel to bifurcation scenario of the spontaneous neural firing rhythms].

Neuronal firing is crucial to the information processing in the nervous system. In order to make a further study of bifurcation scenarios, experiments were performed on neural pacemakers formed at the injured site of rat sciatic nerve subjected to chronic ligatures. We chose the conductance of voltage-dependent potassium ion channels as conditional parameter, and the extracellular calcium concentration as bifurcation parameter, to give a demonstration of how the firing pattern of neural pacemaker responses to dual parameter adjusting. Among 28 preparations observed, 21 were insensitive to dual parameter adjusting since no change of bifurcation scenario structure was detected. On the contrary, the residual 7 preparations showed dramatic bifurcation scenario shifting corresponding to different dual parameter configuration. Briefly, when concentration of 4-aminopyridine (4-AP), a voltage-dependent potassium ion channels blocker, was kept at different level and extracellular Ca2+ concentration was decreased gradually, different bifurcation scenarios of firing patterns were exhibited in an identical neural pacemaker. The two-parameter bifurcation scenarios of experimental neural pacemaker with different parameter configuration were also different. The results show that neural firing pattern is different when the parameter configuration is different, and the bifurcation scenario is a fundamental framework to identify the transitions between firing patterns.

Baroreflex sensitivity is impaired in patients with obstructive jaundice.

BACKGROUND: Obstructive jaundice is associated with enhanced susceptibility to hypotensive shock, renal failure, and toxic effects of endotoxin, which results in high perioperative morbidity and mortality. Since the normal arterial baroreflex function is necessary for hemodynamic homeostasis and improving survival in sepsis, this study aimed to determine whether baroreflex sensitivity was impaired in jaundiced patients. METHODS: Thirty-five patients with obstructive jaundice scheduled for surgery were included, and 30 nonjaundiced patients served as controls. A modified Oxford pharmacologic technique was used for evaluating baroreflex sensitivity immediately before the surgery. Potential factors that may affect baroreflex sensitivity in jaundice, such as liver biochemistry, plasma concentrations of methionine-enkephalin, atrial natriuretic peptide and nitrate, were also measured. RESULTS: Patients with obstructive jaundice had decreased sensitivity in both the sympathetic and vagal components of the baroreflex, as compared with the controls (P < 0.01). There was a significant inverse correlation between plasma atrial natriuretic peptide concentration and decreased sympathetic baroreflex sensitivity in the jaundiced group (r = -0.44, P = 0.008). CONCLUSIONS: Baroreflex sensitivity is impaired in patients with obstructive jaundice, which may contribute to their enhanced susceptibility to the well-known perioperative complications. The underlying mechanisms for such a change may be associated with an increased level of plasma atrial natriuretic peptide.

Changes in 18F-FDG uptake within minutes after chemotherapy in a rabbit VX2 tumor model.

UNLABELLED: The purpose of this study was to investigate whether (18)F-FDG PET/CT can be used for in vivo chemosensitivity testing and to determine the optimal time point for observation. METHODS: Forty-two rabbits with 84 implanted VX2 squamous cell tumors were randomized into a control group (n = 10) and a treatment group (n = 32). (18)F-FDG PET/CT was performed the day before intravenous administration of cisplatin (4 mg/kg) and at 95-100 min (day 0), day 1, day 7, and day 14 afterward. In the control group, (18)F-FDG PET/CT images were acquired at the same time points but without cisplatin administration. Maximum standardized uptake value (SUV) and mean SUV were analyzed. On the basis of tumor volume, we categorized animal tumors into a sensitive group and an insensitive group. If tumor volume doubled by day 7, the tumor was considered insensitive. RESULTS: On day 0, maximum SUV and mean SUV were significantly different between the sensitive group and the insensitive and control groups (P < 0.05 for both). In the sensitive group, the average change from the pretherapy values was -48.96% +/- 12.27% for maximum SUV and -51.63% +/- 10.45% for mean SUV. SUV did not significantly differ between the groups at any other points (days 1-14). On day 0, tumor volume was not significantly different between the control group and the sensitive or insensitive groups. After cisplatin administration, the size of the VX2 xenograft tumors increased slowly. Tumor necrosis fractions on days 7 and 14 were significantly greater in the sensitive group than in the insensitive or control group. Viable tumor cells on days 7 and 14 were less numerous in the sensitive group than in the insensitive or control group. A significant difference in inflammatory cells was seen between the sensitive and insensitive groups on days 7 and 14 (P < 0.05 for both). No significant differences in inflammatory cells or viable tumor cells were seen between the insensitive and control groups at any time points from before therapy to day 14 (P > 0.05 for all). A slight increase in viable tumor cells and inflammatory cells was seen in the sensitive group on day 14, compared with day 7. CONCLUSION: When (18)F-FDG was injected as early as 40 min after administration of chemotherapy, PET showed significantly decreased in vivo uptake of the tracer in chemoresponsive tumors. This finding suggests that (18)F-FDG PET may be able to discriminate sensitive from insensitive tumors if the imaging is performed immediately after a test dose of chemotherapy. The optimal observation time and methodology for various chemotherapy-tumor combinations will need to be studied to confirm whether this approach can be generalized.

Expression of Glut-1 in primary and recurrent head and neck squamous cell carcinomas, and compared with 2-[18F]fluoro-2-deoxy-D-glucose accumulation in positron emission tomography.

The aim of the study was to investigate the pattern of glucose transporter-1 (Glut-1) expression in primary and recurrent head and neck squamous cell carcinomas (HNSCCAs) and the relation between Glut-1 expression and 2-[18F]fluoro-2-deoxy-D-glucose - positron emission tomography (FDG-PET). Standardised uptake values (SUVs) were used to evaluate FDG uptake by the tumour. Sections were stained immunohistochemically for Glut-1, which showed that high SUVs were seen in all HNSCCAs, and patients with higher T stage tumours or less well-differentiated tumours showed significantly higher SUVs than those with lower stage tumours or better-differentiated tumours (P=0.001 and 0.04, respectively). Glut-1 immunostaining was present in all cases. The Glut-1 staining index in primary HNSCCAs was significantly lower than that in recurrent HNSCCAs (P=0.03), and the index of better-differentiated tumours lower than that of poorly-differentiated tumours (P=0.02). However, there was no significant correlation between SUV(mean) and the Glut-1 staining index. In conclusion, our data suggest that high FDG uptakes were seen with overexpression of Glut-1 in primary and recurrent HNSCCAs. SUV(mean) was related to tumour T stage and grade of differentiation, which indicated that SUV was helpful in evaluating tumours. The expression of Glut-1 in recurrent HNSCCAs was higher than that in primary HNSCCAs, and in poorly-differentiated HNSCCAs higher than in better-differentiated HNSCCAs, which indicated that Glut-1 may have a useful role as a predictor for poor prognosis in HNSCCAs. However, there was no significant correlation between FDG accumulation and Glut-1 expression.

[Effect and mechnaisim of GLU and GABA in OFC on gastric motility].

AIM: To Investigate the effect of glutamate (Glu) and gamma-aminobutyric acid(GABA) in orbitofrontal cortex (OFC) on regulation of gastric motility. METHODS: Using microinjection in OFC,together with lesion of related nucleus,and recording the intragastric pressure(IGP). RESULTS: (1) Microinjection of Glu in OFC caused a significant reduce of the amplitude of gastric motility, this effect could be reverse by lesion of amygdala, while lesion of LC had no influence on the effect of Glu. (2) microinjection of GABA in OFC could increase the amplitude of gastric motility significantly,and lesion of LC could abolish this effect,while lesion of amygdala could enhance the effect of GABA more. CONCLUSION: Microinjection of Glu in OFC may enhance the normal inhibitory effect of amygdale on gastric motility, and the effect of microinjection of GABA in OFC on gastric motility is closely related with LC.

[Effect of naloxone on expression of Bcl-2 protein and tumor necrosis factor-alpha in rats with acute myocardial ischemia/reperfusion injury].

OBJECTIVE: To investigate the effect of naloxone on myocardial cell apoptosis and apoptosis-related gene Bcl-2 in rats with acute myocardial ischemia/reperfusion (AMIR) injury, and explore the mechanism of protective effect of naloxone on myocardium. METHODS: Thirty SD rats were randomly divided into three groups (n=10): ischemia/reperfusion group, naloxone preconditioning group (naloxone was injected intraperitoneally 10 minutes before ischemia and 2 hours after reperfusion), and normal control group. The left anterior descending branch (LAD) of rat coronary artery was tied and un-tied in ischemia/reperfusion group and naloxone preconditioning group to establish the AMIR model in rats. The animals were then sacrificed and hearts were harvested. The expression of Bcl-2 protein was observed by immunohistochemical technique. Radioimmunoassay (RIA) was used to determine tumor necrosis factor-alpha (TNF-alpha) in serum. RESULTS: In the normal control group, there was no Bcl-2 expression and TNF-alpha level was (0.39+/-0.06) mug/L. Higher expression of Bcl-2 and increased TNF-alpha levels were found in ischemia/reperfusion group. The expression of Bcl-2 protein increased significantly [(+++) vs. (+)], and TNF-alpha was significantly lower in naloxone preconditioning group than those in the normal control group [(0.55+/-0.12) microg/L vs. (0.86+/-0.11) microg/L, P<0.01]. CONCLUSION: Naloxone can protect myocardium from AMIR injury by inhibiting the apoptosis of cardiomyocytes induced by TNF-alpha and up-regulating protein expression of bcl-2 gene.