Physiologically based pharmacokinetic-pharmacodynamic modeling for prediction of vonoprazan pharmacokinetics and its inhibition on gastric acid secretion following intravenous/oral administration to rats, dogs and humans.

Vonoprazan is characterized as having a long-lasting antisecretory effect on gastric acid. In this study we developed a physiologically based pharmacokinetic (PBPK)-pharmacodynamic (PD) model linking to stomach to simultaneously predict vonoprazan pharmacokinetics and its antisecretory effects following administration to rats, dogs, and humans based on in vitro parameters. The vonoprazan disposition in the stomach was illustrated using a limited-membrane model. In vitro metabolic and transport parameters were derived from hepatic microsomes and Caco-2 cells, respectively. We found the most predicted plasma concentrations and pharmacokinetic parameters of vonoprazan in rats, dogs and humans were within twofold errors of the observed data. Free vonoprazan concentrations (fu × C2) in the stomach were simulated and linked to the antisecretory effects of the drug (I) (increases in pH or acid output) using the fomula dI/dt = k × fu × C2 × (Imax - I) - kd × I. The vonoprazan dissociation rate constant kd (0.00246 min-1) and inhibition index KI (35 nM) for H+/K+-ATPase were obtained from literatures. The vonoprazan-H+/K+-ATPase binding rate constant k was 0.07028 min-1· µM-1 using ratio of kd to KI. The predicted antisecretory effects were consistent with the observations following intravenous administration to rats (0.7 and 1.0 mg/kg), oral administration to dogs (0.3 and 1.0 mg/kg) and oral single dose or multidose to humans (20, 30, and 40 mg). Simulations showed that vonoprazan concentrations in stomach were 1000-fold higher than those in the plasma at 24 h following administration to human. Vonoprazan pharmacokinetics and its antisecretory effects may be predicted from in vitro data using the PBPK-PD model of the stomach. These findings may highlight 24-h antisecretory effects of vonoprazan in humans following single-dose or the sustained inhibition throughout each 24-h dosing interval during multidose administration.

Physiologically-Based Pharmacokinetic-Pharmacodynamics Model Characterizing CYP2C19 Polymorphisms to Predict Clopidogrel Pharmacokinetics and Its Anti-Platelet Aggregation Effect Following Oral Administration to Coronary Artery Disease Patients With or Without Diabetes.

Background and Objective: Clopidogrel (CLOP) is commonly used in coronary artery disease (CAD) patients with or without diabetes (DM), but these patients often suffer CLOP resistance, especially those with diabetes. This study was aimed to develop a physiologically-based pharmacokinetic-pharmacodynamic (PBPK-PD) model to describe the pharmacokinetics and pharmacodynamics of clopidogrel active metabolite (CLOP-AM) in CAD patients with or without DM. Methods: The PBPK-PD model was first established and validated in healthy subjects and then in CAD patients with or without DM. The influences of CYP2C19, CYP2C9, CYP3A4, carboxylesterase 1 (CES1), gastrointestinal transit rates (K t,i) and platelets response to CLOP-AM (k irre) on predicted pharmacokinetics and pharmacodynamics were investigated, followed with their individual and integrated effects on CLOP-AM pharmacokinetics due to changes in DM status. Results: Most predictions fell within 0.5-2.0 folds of observations, indicating successful predictions. Sensitivity analysis showed that contributions of interested factors to pharmacodynamics were CES1> k irre> K t,i> CYP2C19 > CYP3A4> CYP2C9. Mimicked analysis showed that the decreased exposure of CLOP-AM by DM was mainly attributed to increased CES1 activity, followed by decreased CYP2C19 activity. Conclusion: The pharmacokinetics and pharmacodynamics of CLOP-AM were successfully predicted using the developed PBPK-PD model. Clopidogrel resistance by DM was the integrated effects of altered K t,i, CYP2C19, CYP3A4, CES1 and k irre.

Efficacy of afatinib, an irreversible ErbB family blocker, in the treatment of intracerebral metastases of non-small cell lung cancer in mice.

Few effective therapeutic options are currently available for the treatment of non-small cell lung cancer (NSCLC) with brain metastases (BM). Recent evidence shows that NSCLC patients with BMs respond well to afatinib, but little is known about the underlying mechanisms. In this study, we evaluated the efficacy of afatinib in treatment of BMs in mice and investigated whether afatinib could actively penetrate the brain-blood barrier and bind to its target. NSCLC BM model was established in nude mice by intracerebral injection of PC-9.luc cells. The tumors were measured weekly using in vivo quantitative bioluminescence. The mice are administrated afatinib (15, 30 mg·kg-1·d-1, ig) for 14 d. The antitumor efficacy of afatinib was determined by tumor growth inhibition (TGI), which was calculated as [1-(change of tumor volume in treatment group/control group)×100]. Pharmacokinetic characteristics were measure in mice receiving a single dose of afatinib (30 mg/kg, ig). Pharmacodynamics of afatinib was also assessed by detecting the expression of pEGFR (Tyr1068) in brain tumor foci using immunohistochemistry. Administration of afatinib (15, 30 mg·kg-1·d-1) dose-dependently inhibited PC-9 tumor growth in the brain with a TGI of 90.2% and 105%, respectively, on d 14. After administration of afatinib (30 mg/kg), the plasma concentration of afatinib was 91.4±31.2 nmol/L at 0.5 h, reached a peak (417.1±119.9 nmol/L) at 1 h, and was still detected after 24 h. The cerebrospinal fluid (CSF) concentrations followed a similar pattern. The T1/2 values of afatinib in plasma and CSF were 5.0 and 3.7 h, respectively. The AUC(0-24 h) values for plasma and CSF were 2375.5 and 29.1 nmol/h, respectively. The plasma and CSF concentrations were correlated (r=0.844, P<0.01). Pharmacodynamics study showed that the expression levels of pEGFR were reduced by 90% 1 h after afatinib administration. The Emax was 86.5%, and the EC50 was 0.26 nmol/L. A positive correlation between CSF concentrations and pEGFR modulation was revealed. Afatinib penetrates the BBB in NSCLC BM mice and contributes to the brain tumor response. The CSF exposure level is correlated with the plasma level, which in turn is correlated with the modulation of pEGFR in the tumor tissues. The results support for the potential application of afatinib in NSCLC patients with BMs.

Clonality analysis of neuroendocrine cells in gastric adenocarcinoma.

AIM: To achieve a better understanding of the origination of neuroendocrine (NE) cells in gastric adenocarcinoma. METHODS: In this study, 120 cases of gastric adenocarcinoma were obtained. First, frozen section-immunohistochemistrical samples were selected from a large quantity of neuroendocrine cells. Second, laser capture microdissection was used to get target cells from gastric adenocarcinoma and whole genome amplification was applied to get a large quantity of DNA for further study. Third, genome-wide microsatellite abnormalities [microsatellite instability (MSI), loss of heterozygosity (LOH)] and p53 mutation were detected by polymerase chain reaction (PCR)-single-strand conformation polymer- phism-silver staining and PCR-sequencing in order to identify the clonality of NE cells. RESULTS: The total incidence rate of MSI was 27.4%, while LOH was 17.9%. Ten cases had a highest concordance for the two types of cells. The other samples had similar microsatellite changes, except for cases 7 and 10. Concordant p53 mutations exhibited in sample 4, 14, 21 and 27, and there were different mutations between two kinds of cells in case 7. In case 17, mutation took place only in adenocarcinoma cells. p53 mutation was closely related with degree of differentiation, tumor-node-metastasis stage, vessel invasion and lymph node metastasis. In brief, NE and adenocarcinoma cells showed the same MSI, LOH or p53 mutation in most cases (27/30). In the other three cases, different MSI, LOH or p53 mutation occurred. CONCLUSION: NE and the gastric adenocarcinoma cells may mainly derive from the same stem cells, but the remaining cases showing different origin needs further investigation.

[Expression of BRAF V600E mutation in different thyroid lesions].

OBJECTIVE: To evaluate the expression of BRAF V600E mutation in 240 Chinese patients with thyroid lesions. METHODS: Two hundred and forty Chinese patients with thyroid lesions, including 129 papillary thyroid carcinomas (PTC), 12 follicular carcinomas, 4 medullary carcinomas, 30 adenomas, 30 nodular goiters, and 35 papillary hyperplasia. DNA was extracted from thyroid biopsy and paraffin embedded thyroid tissues, and the expression of BRAF V600E mutation was detected by polymerase chain reaction and DNA sequencing assays. RESULTS: The presence of BRAF V600E mutation was found in 61 of the total group of 240 cases (25.4%). It was only detected in PTC (47.3%), and not detected in other types of malignant and benign thyroid lesions. There was a statistically significant difference between the expression of BRAF V600E mutation in classic type PTC (49.6%) and in follicular type PTC (12.5%,P < 0.05), but statistical data did not show any correlation between BRAF V600E mutation and clinicopathologic parameters in PTC (P > 0.05). CONCLUSIONS: BRAF V600E mutation has a significant correlation with PTC and the detection of BRAF V600E mutation may be used as an important prognostic marker of PTC. Our new method of DNA extraction from paraffin embedded tissues is efficient and inexpensive.

Expression of type IV collagen, metalloproteinase-2, metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in laryngeal squamous cell carcinomas.

OBJECTIVE: To investigate the significance of type IV collagen, metalloproteinase-2 (MMP-2), metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) expression in laryngeal squamous cell carcinomas (LSCCs). METHODS: Expression was quantified in 44 LSCC and 22 adjacent non-cancer normal tissues using a streptavidin-peroxidase conjugated immunohistochemistry and associations between the levels of the four proteins and clinicopathological characteristics in LSCC were analyzed. RESULTS: Significantly different expression of all four proteins was observed in LSCC and adjacent non-cancer normal tissues (P<0.05). Expression of type IV collagen correlated with primary cancer status (P = 0.04), clinical stage (P = 0.04) and histological grade (P = 0.01). Expression of MMP-9 correlated with the location of the tumor (P = 0.04), cervical node metastasis (P = 0.02) and prognosis (P = 0.02). The (MMP-2+MMP-9)/TIMP-1 score was associated with the prognosis of LSCC (P < 0.01). CONCLUSIONS: This study suggests that expression of type IV collagen and its regulators is strongly associated with the development of LSCC. Type IV collagen and MMP-9 may be more valuable than MMP-2 and TIMP-1 for the evaluation of clinical characteristics. Regulation of type IV collagen may contribute to the balance of MMPs and TIMPs in LSCC.

Pathological changes at early stage of multiple organ injury in a rat model of severe acute pancreatitis.

BACKGROUND: Severe acute pancreatitis (SAP) is a commonly seen acute abdominal syndrome characterized by sudden onset, rapid progression and high mortality rate. The damage in peripheral organs may be more severe than that in the pancreas, and can even lead to multiple organ dysfunction. It is critical to recognize early pathological changes in multiple organs. This study aimed to assess the early pathological features of damaged organs in a rat model of SAP. METHODS: Thirty clean grade healthy male Sprague-Dawley rats weighing 250-300 g were randomly divided into a model control group (n=15) and a sham-operated group (n=15). The SAP rat model was induced by sodium taurocholate. Samples of blood and from multiple organs were collected 3 hours after operation. We assessed the levels of IL-6, TNF-alpha, PLA2, NO, ET-1, MDA, amylases and endotoxin in blood and observed the early pathological changes in multiple damaged organs. RESULTS: Levels of IL-6, TNF-alpha, PLA2, NO, ET-1 and MDA in serum and of amylase and endotoxin in plasma of the model control group rats were significantly higher than those of the sham-operated group (P<0.01). Different degrees of pathological change were observed in multiple damaged organs. CONCLUSION: Multiple organ injury may occur at the early stage of SAP in rats.

Effects of a selective cyclooxygenase-1 inhibitor in SKOV-3 ovarian carcinoma xenograft-bearing mice.

To evaluate the effect of a cyclooxygenase-1 (COX-1) inhibitor, SC-560, on the growth inhibition of s.c. human ovarian SKOV-3 carcinoma and on angiogenesis. Human ovarian SKOV-3 carcinoma cells xenograft-bearing mice were treated with SC-560, a COX-1-selective inhibitor, 6 mg/kg alone i.g. daily, and i.p. injections of cisplatin 3 mg/kg every other day for 21 days. Prostaglandin E(2) (PGE(2)) levels were determined by ELISA. Microvessel density (MVD) of ovarian carcinoma was determined with anti-CD(34) as the label by immunohistochemistry. In addition, the expression of COX-1 at protein levels in the control group was detected by immunohistochemistry. SC-560 reduced the growth of tumors when SKOV-3 cells were xenografted in nude female mice. The inhibitory rates in SC-560 group and cisplatin group were 47.1% and 51.7%, respectively, which is significant statistically compared to that of control group (all, P < 0.05). In treatment groups, SC-560 significantly reduced intratumor PGE(2) levels (P < 0.01). MVDs in SC-560 group were 35.73 +/- 9.87, which are significant statistically compared to that of control group (74.33 +/- 9.50) (P < 0.01). COX-1, not COX-2, protein levels are elevated in tumor tissues. These findings may implicate COX-1 as a suitable target for the treatment of ovarian cancer and that antiangiogenic therapy can be used to inhibit ovarian cancer growth.

Hepatic angiomyolipoma: dynamic computed tomography features and clinical correlation.

AIM: To study the dynamic computed tomography (CT) features of hepatic angiomyolipoma (AML) in patients with or without tuberous sclerosis complex (TSC). METHODS: The clinical information, CT findings and histopathological results of hepatic AML were analyzed retrospectively in 10 patients. RESULTS: Hepatic AML was prone to occur in female patients (7/10), and most of the patients (8/10) had no specific symptoms. All tumors presented as well-defined, unenveloped nodules in the liver. Six patients with sporadic hepatic AML had a solitary hepatic nodule with a definite fat component. Non-fat components of the hepatic lesions were enhanced earlier and persistently. Prominent central vessels were noted in the portal venous phase in three patients. In four patients with hepatic AML and TSC, most of the nodules were within the peripheral liver. Seven fat-deficient nodules were found with earlier contrast enhancement and rapid contrast material washout in two patients. Lymphangioleiomyomatosis was found in one patient. CONCLUSION: Imaging features of hepatic AML are characteristic. Correct diagnosis preoperatively can be made in combination with clinical features.

Pathological changes in multiple organs of rats with severe acute pancreatitis treated by baicalin and octreotide.

BACKGROUND: Severe acute pancreatitis (SAP) features fatal pathogenetic conditions and high mortality rate. The study of SAP complicated with multiple organ injuries is of important significance. In this study, we explored the protective effect of baicalin on multiple organs of SAP rats and compared it with that of octreotide through light and electron microscopic observations of the pathological changes. METHODS: The improved Aho method was used to prepare SAP rat models. These rats were then randomly divided into a sham-operated group (n=45), a model control group (n=45), baicalin-treated group (n=45) and octreotide-treated group (n=45). Based on the difference in time points after operation, these groups were subdivided into 3, 6 and 12 hour subgroups (n=15). At the corresponding time point after operation, the mortality rate of rats was recorded, and then the rats were humanely killed to take samples of multiple organs that were subsequently examined for pathological changes under light and electron microscopy. RESULTS: At 12 hours after operation, the mortality rate of rats in the baicalin- and octreotide-treated groups was lower than that in the model control group (P<0.05). Compared to the model control group, the pathological changes and pathological scores in the baicalin- and octreotide-treated groups were mitigated and relieved to varying degrees. The pathological changes under electron microscopy were also improved. CONCLUSIONS: Both baicalin and octreotide show good protective effects on multiple organs of SAP rats. Baicalin as a new drug has good prospects in the treatment of SAP.

Effects of a cyclooxygenase-1-selective inhibitor in a mouse model of ovarian cancer, administered alone or in combination with ibuprofen, a nonselective cyclooxygenase inhibitor.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to be potent inhibitors of the cyclooxygenases. The present study was designed to investigate the effects of a cyclooxygenase (COX)-1 inhibitor, SC-560, administered alone or in combination with ibuprofen on the growth inhibition of s.c. human ovarian SKOV-3 carcinoma and on angiogenesis. The effects of SC-560 and ibuprofen on tumor growth inhibition have been examined in mouse ovarian cancer models. Angiogenesis of both COX inhibitors was measured by reverse-transcription polymerase chain reaction (RT-PCR) and immunohistochemistry. Prostaglandin E(2) (PGE(2)) levels in tumor tissues of mice were also determined by ELISA. The inhibitory rates in SC-560 group alone and in combination with ibuprofen group were 21.21% and 41.55%, respectively. In combination therapy with SC-560 and ibuprofen, tumor volumes were significantly reduced compared with that of control group (P < 0.05). In treatment groups, both COX inhibitors significantly reduced intratumor PGE(2) levels (all P < 0.01). Microvessel density (MVD) in tumor tissues were significantly decreased from 80.90 +/- 5.14 in vehicle-treated to 40.70 +/- 10.45 and 38.90 +/- 8.41 in SC-560 group alone and combination ibuprofen therapy (all P < 0.01). Ibuprofen was similar to the cyclooxygenase-1-selective inhibitor SC-560 in its ability to suppress the values of MVD of tumor tissues. SC-560 administered alone or in combination with ibuprofen inhibited the COX-associated up-regulation of VEGF. These studies demonstrate synergism between two COX inhibitors and that antiangiogenic therapy can be used to inhibit ovarian cancer growth.

Effects of a selective cyclooxygenase-2 inhibitor, nimesulide, on the growth of ovarian carcinoma in vivo.

New therapies against cancer are based on targeting cyclooxygenase-2 (COX-2). Whether COX-2 inhibitor therapy would be beneficial in the prevention and/or treatment of ovarian cancer still remains unclear. This study was designed to investigate whether nimesulide, a COX-2 selective inhibitor, could suppress tumor growth in implanted ovarian carcinoma mice and to explore the molecular mechanisms. Human ovarian SKOV-3 carcinoma cells xenograft-bearing mice were treated with nimesulide 62.5 mg/kg or 250 mg/kg alone i.g., daily for 21 days. Microvessel density (MVD) of ovarian carcinoma was determined with anti-CD(34) as the label. Prostaglandin E2 (PGE2) levels were also determined by ELISA. In addition, the expression of COX-2 and COX-1 at protein and mRNA levels in the control groups was also detected by immunohistochemistry and reverse-transcription polymerase chain reaction (RT-PCR). Nimesulide treatment showed a dose-dependent growth-inhibitory effect of human ovarian SKOV-3 tumors. The inhibitory rates in nimesulide 62.5 mg/kg group and 250 mg/kg group were 20.40% and 50.55% respectively, however, which is not significant statistically compared with that of control group (P > 0.05). In treatment groups, nimesulide significantly reduced intratumor PGE2 levels (all, P < 0.01). Microvessel densities in treatment groups were 61.20 +/- 1.67 (62.5 mg/kg) and 66.27 +/- 1.20 (250 mg/kg), which are significant statistically compared with that of control group (79.97 +/- 1.07) (all, P < 0.01). However, COX-1, not COX-2, mRNA, and protein levels are elevated in tumor tissues. Nimesulide decreased microvessel density is associated with the reduction of PGE2 levels but without affecting growth inhibition and the expression of COX-2. Importantly, tumor growth implanted in SKOV-3 mice was not significantly attenuated suggesting that COX-1 in ovarian carcinoma tissue also has an important role in tumor growth. These findings may implicate COX-1 as a suitable target for the treatment of ovarian cancer.

Coincidence of hepatocelluar carcinoma and hepatic angiomyolipomas in tuberous sclerosis complex: a case report.

Tuberous sclerosis complex (TSC) is a dominantly inherited disorder which characterized by the growth of harmatomatous in multiple organs. Unlike the common development of renal angiomyolipoma, hepatic angiomyolipoma rarely occur in patients with TSC. We report here a patient with hepatic angiomyolipomas and concurrent hepatocellular carcinoma in TSC. This represents the first reported case in English literature. In this patient, multiple hepatic angiomyolipomas were diagnosed with recognition of their fat components and typical clinical settings. Hepatocellular carcinoma in the left liver lobe was definitely diagnosed by US guided biopsy. In such clinical settings, fat containing lesions in liver can be reasonably treated as angiomyolipomas, but non fat containing lesions must be differentiated from hepatocellular carcinoma, imaging guided biopsy can be adopted to confirm the diagnosis.