Co-expression of Bcl-2 protein and vascular endothelial growth factor in hepatocellular carcinomas treated by chemoembolization

AIMS/BACKGROUND

Transcatheter arterial chemoembolization (TAE) of hepatocellular carcinoma (HCC) causes anoxia. Escape of cancer cells from anoxic injury may be enhanced by induction of proteins which provide resistance to apoptosis.

METHODS

We examined HCCs immunohistochemically for Bcl-2, vascular endothelial growth factor (VEGF), p53, and Ki67. The staining intensity for VEGF, a protein induced by anoxia, was assessed morphometrically with a computer-assisted image-analyzer.

RESULTS

The frequency of Bcl-2 positive cells was higher in HCCs that had undergone TAE (TAE HCC) than that in HCCs that had not undergone TAE (41.75+/-15.06 vs. 1.01+/-0.79 cells/1000 cells, p = 0.0173). The frequency of p53- or Ki67-positive cells was not increased after TAE. Of 12 TAE HCCs, 7 had Bcl-2 positive HCC cells and 6 had clusters of Bcl-2 positive cells. In contrast, 2 of 11 HCCs that had not undergone TAE had only a few, sporadically distributed, Bcl-2-positive cells. The staining intensity for VEGF was higher in Bcl-2 positive than in Bcl-2 negative areas (1.208+/-0.091 vs. 1.071+/-0.017, p = 0.0222). Furthermore, the VEGF staining intensity in Bcl-2 positive areas of TAE HCCs was higher than in Bcl-2 negative areas (1.296+/-0.126 vs. 1.066+/-0.024, p = 0.0186), while in HCCs that had not undergone TAE the staining intensity was similar.

CONCLUSIONS

TAE of HCC can induce Bcl-2 expression, possibly through anoxic stress.

Simultaneous measurements of serum alpha-fetoprotein and protein induced by vitamin K absence for detecting hepatocellular carcinoma. South Tohoku District Study Group

OBJECTIVE

We evaluated the measurements of serum alpha-fetoprotein (AFP) and the protein induced by vitamin K absence (PIVKA-II) in 734 patients with chronic hepatitis (CH) and liver cirrhosis (LC) who had been followed-up for the development of hepatocellular carcinoma (HCC).

METHODS

Serum AFP and PIVKA-II were measured every month and abdominal ultrasonography was performed every 3 months. Youden's index (sensitivity + specificity -1) was calculated.

RESULTS

On an average follow-up period of 374.5 days, HCC was detected in three HBsAg-positive LC patients (10.0%/yr), four anti-HCV-positive CH patients (1.35%/yr), 21 anti-HCV-positive LC patients (7.8%/yr), and one patient with both HBsAg- and anti-HCV-positive LC (22.7%/yr). At the time of HCC detection, the size of HCC was 4.7+/-0.6 (mean +/- SD) cm in HBsAg-positive patients and 2.4+/-1.3 cm in anti-HCV-positive patents. Cut-off values of 20 ng/ml for AFP (Youden's index = 0.422) and 60 mAU/ml for PIVKA-II (Youden's index = 0.316) gave the highest index for each marker. When these two markers were combined, cut-off values of 40 ng/ml for AFP and 80 mAU/ml for PIVKA-II gave the highest index (Youden's index = 0.500, sensitivity = 65.5%, specificity = 85.5%, positive predictable value = 14.8%, negative predictable value = 98.3%). The levels of AFP or PIVKA-II increased within three months before the detection of HCC.

CONCLUSIONS

Simultaneous measurements of serum AFP and PIVKA-II levels that are performed every 3 months are useful for detecting a developing HCC. The optimal cut-off values for AFP and PIVKA-II may be 40 ng/ml and 80 mAU/ml, respectively.

FK143, a novel nonsteroidal inhibitor of steroid 5 alpha-reductase: (1) In vitro effects on human and animal prostatic enzymes

Steroid 5 alpha-reductase is an enzyme which converts testosterone into 5 alpha-dihydrotestosterone (DHT) and is implicated in the pathogenesis of benign prostatic hyperplasia (BPH) in men. We studied in vitro effects of FK143, a nonsteroidal new compound, on 5 alpha-reductase in human and animal prostates. Prostates were obtained from Wistar rats, Beagle dogs, and Cynomolgus monkeys as well as prostatic tissue from BPH patients obtained by the prostatectomy. Nuclear membrane fraction of prostates showed pH dependent 5 alpha-reductase activities, and inhibitory effects of drugs were assayed at pH 6.5. FK143 inhibited human prostatic 5 alpha-reductase in a dose-dependent manner with an IC50 of 1.9 nM and also inhibited animal 5 alpha-reductases with similar IC50 values. FK143 inhibited human and rat 5 alpha-reductases in a noncompetitive fashion while finasteride, a steroidal 5 alpha-reductase inhibitor, showed competitive inhibition. The affinities of FK143 for the human 5 alpha-reductase is constant at pH 5 and 6.5. No inhibitory effects were shown to other oxidoreductases. These results indicate that FK143 is a new type of potent and selective 5 alpha-reductase inhibitor.

FK330, a novel inducible nitric oxide synthase inhibitor, prevents ischemia and reperfusion injury in rat liver transplantation

Nitric oxide (NO), produced via inducible NO synthase (iNOS), is implicated in the pathophysiology of liver ischemia/reperfusion injury (IRI). We examined the effects of a novel iNOS inhibitor, FK330 (FR260330), in well-defined rat liver IRI models. In a model of liver cold ischemia followed by ex vivo reperfusion, treatment with FK330 improved portal venous flow, increased bile production and decreased hepatocellular damage. FK330 prevented IRI in rat model of 40-h cold ischemia followed by syngeneic orthotopic liver transplantation (OLT), as evidenced by: (1) increased OLT survival (from 20% to 80%); (2) decreased hepatocellular damage (serum glutamic oxaloacetic transaminase/glutamic pyruvic transaminase levels); (3) improved histological features of IRI; (4) reduced intrahepatic leukocyte infiltration, as evidenced by decreased expression of P-selectin/intracellular adhesion molecule 1, ED-1/CD3 cells and neutrophils; (5) depressed lymphocyte activation, as evidenced by expression of pro-inflammatory cytokine (TNF-alpha, IL-1beta, IL-6) and chemokine (IP-10, MCP-1, MIP-2) programs; (6) prevented hepatic apoptosis and down-regulated Bax/Bcl-2 ratio. Thus, by modulating leukocyte trafficking and cell activation patterns, treatment of rats with FK330, a specific iNOS inhibitor, prevented liver IRI. These results provide the rationale for novel therapeutic approaches to maximize organ donor pool through the safer use of liver grafts despite prolonged periods of cold ischemia.

Mutational analysis of the domain structure of mouse protein phosphatase 2Cbeta

The structures of five distinct isoforms of mammalian protein phosphatase 2Cbeta (PP2Cbeta-1, -2, -3, -4 and -5) have previously been found to differ only at their C-terminal regions. In the present study, we performed mutational analysis of recombinant mouse PP2Cbeta-1 to determine the functional domains of the molecule and elucidate the biochemical significance of the structural differences in the isoforms. Differences in affinity for [32P]phosphohistone but not for [32P]phosphocasein were observed among the five PP2Cbeta isoforms. Deletion of 12 amino acids from the C-terminal end, which form a unique sequence for PP2Cbeta-1, caused a 35% loss of activity against [32P]phosphohistone but no loss of activity against [32P]phosphocasein. Deletion of up to 78 amino acids from this end did not cause any further alteration in activity, whereas deletion of 100 amino acids totally eliminated the activity against both [32P]phosphohistone and [32P]phosphocasein. On the other hand, deletion of 11 amino acids from the N-terminal end caused a 97% loss of enzyme activity, and further deletions caused a total loss of activity. Substitution of any of the six specific amino acids among 16 tested in this study, which were located among the 250 N-terminal residues, caused 98-100% loss of enzyme activity. Among these amino acids, three (Glu-38, -60 and -243) have recently been reported to be essential for the binding of metal ions in the catalytic site of the PP2C molecule [Das, Helps, Cohen and Barford (1996) EMBO J. 15, 6798-6809]. These observations indicate that PP2Cbeta is composed of at least two distinct functional domains, an N-terminal catalytic domain of about 310 amino acids and the remaining C-terminal domain, which is involved in determination of substrate specificity.

High proportion of extrapulmonary tuberculosis in a low prevalence setting: a retrospective cohort study

OBJECTIVES

The proportion of extrapulmonary tuberculosis (EPTB) cases in the United States (US) has been rising due to a slower rate of decline in EPTB compared to pulmonary tuberculosis (PTB). The purpose of this study was to characterise the clinical and treatment differences between EPTB and PTB patients, and identify patient factors associated with EPTB.

STUDY DESIGN

We performed a retrospective cohort study of active tuberculosis (TB) cases treated at the Baltimore City Health Department between 2008 and 2013.

METHODS

We categorised patients as having 'only PTB' (infection in the lung parenchyma), 'EPTB/PTB' (infection in the lung and an additional site), and 'only EPTB' (infection not involving the lung). Pearson's chi-squared tests were used to evaluate categorical variables and compare clinical and demographic differences between only PTB, only EPTB, and EPTB/PTB patients. Student t-tests and one-way analysis of variance tests were utilised to assess continuous variables and to compare treatment differences.

RESULTS

One hundred and sixty-three patients were treated for TB; 39.3% had some form of EPTB (either EPTB/PTB or only EPTB). There was no difference found between EPTB, PTB, and EPTB/PTB patients with respect to HIV status, gender, race, foreign-born status, or mean age. Patients with only EPTB were less likely than patients with some form of PTB (only PTB or EPTB/PTB) to present with cough (30.4% vs 61.5%; P < 0.001), night sweats (10.9% vs 39.3%; P < 0.001), and weight loss (28.3% vs 47.9%; P = 0.023). Patients with some form of EPTB were also more likely to be hospitalised postdiagnosis compared to patients with only PTB (39.1% vs 20.2%; P = 0.009), and to have longer mean durations of treatment (37.9 weeks [SD = 11.1] vs 31.8 weeks [SD = 8.1]; P < 0.001).

CONCLUSIONS

EPTB patients present with atypical symptoms, undergo prolonged treatment, and experience increased hospitalisations. In order to improve diagnostic algorithms and treatment modalities, EPTB must be further characterised.

Stereoselective total synthesis of (+)-myriocin from D-mannose

The stereoselective total synthesis of myriocin 1 from D-mannose is described; the carbon framework with three contiguous chiral centers including a tetra-substituted carbon with nitrogen was effectively constructed using Overman rearrangement as the key reaction.

Total synthesis of spicamycin amino nucleoside

[formula: see text] The first total synthesis of spicamycin amino nucleoside 2 has been achieved. The aminoheptose unit 5 was prepared stereoselectively from myo-inositol, and the characteristic N-glycoside linkage was constructed by way of Pd-catalyzed coupling reaction of 5 with 6-chloropurine derivative 6.

Spermine promotes the survival of primary cultured brain neurons

The effects of polyamines on the survival of hippocampal and cerebellar neurons in primary culture were investigated. Putrescine and spermidine showed no effects on the neuronal survival, while spermine increased significantly the number of surviving neurons in both hippocampal and cerebellar cultures. The concentration-effect curve for spermine was bell-shaped with the maximum effect at a concentration of 10(-8) M. The survival-promoting effect of spermine was blocked by ifenprodil, an antagonist at the polyamine site of the NMDA receptor channel complex. These results suggest that spermine exerts trophic effects on brain neurons through an ifenprodil-sensitive mechanism.

Spermine facilitates the generation of long-term potentiation of evoked potential in the dentate gyrus of anesthetized rats

The effects of the polyamines, spermine, spermidine and putrescine, on long-term potentiation (LTP) of evoked potential were investigated in the dentate gyrus of anesthetized rats. Injection of 5 nmol spermine into the lateral ventricle did not influence the basal amplitude of the population spike, but significantly enhanced the potentiation induced by subthreshold tetanic stimulation (20 pulses at 60 Hz). The effect of spermine resulted in facilitation of LTP generation. Injection of the same dose of spermidine or putrescine affected neither the basal response nor the potentiation induced by subthreshold tetanus at all, indicating that the LTP-facilitating effect is specific to spermine. Furthermore, the LTP-facilitating effect of spermine was dose-dependent in the range of 0.5-50 nmol. When 5 nmol ifenprodil, an antagonist at the polyamine site of the NMDA receptor channel complex, was concomitantly injected, spermine could not facilitate the generation of LTP. Since injection of ifenprodil alone did not influence the generation of LTP, it is probable that ifenprodil specifically blocks the effect of spermine. These results suggest that spermine facilitates the generation of hippocampal LTP, probably through an ifenprodil-sensitive polyamine site associated with the NMDA receptor.

FK143, a novel nonsteroidal inhibitor of steroid 5 alpha-reductase: (2) In vivo effects on rat and dog prostates

FK143 is a nonsteroidal new inhibitor of steroid 5 alpha-reductase, an enzyme which converts testosterone into 5 alpha-dihydrotestosterone (DHT). We studied in vivo effects of FK143 on rat and dog prostates. FK143 was orally administered to mature male rats for 14 days. At doses above 1 mg/kg, FK143 significantly reduced the wet weights of the ventral prostate and seminal vesicle, but showed no effects on those of the epididymis, testis, and adrenal. Growth of ventral prostate and seminal vesicle was induced by the subcutaneous injection of testosterone propionate (TP) in the castrated young rats and was reduced by FK143 administration at doses above 3.2 mg/kg, while growth induced by 5 alpha-dihydrotestosterone propionate (DHTP) was not affected. FK143 had no binding affinity for the rat androgen receptor. FK143 showed neither estrogenic and antiestrogenic effects on the rat uterus nor androgenic effect on the rat prostate. Concentration of testosterone and DHT in the rat and dog prostates were measured by GC-MS, and administration of 10 mg/kg of FK143 significantly reduced the intraprostatic concentration of DHT. These results indicate that FK143 reduced the prostate growth by inhibiting 5 alpha-reductase activities in the prostates.

Hepatocellular carcinomas supplied by inferior phrenic arteries

PURPOSE

To assess the arterial supply to hepatocellular carcinomas (HCCs) by inferior phrenic arteries (IPA).

MATERIAL AND METHODS

A total of 126 consecutive cases of HCC were studied by contract-enhanced CT and conventional arteriography. Blood supply from an IPA was suspected when the size of the HCC mass as seen on contrast-enhanced CT did not match the size of the tumor mass as seen on hepatic arteriography. Inferior phrenic arteriography was employed to confirm these findings. HCCs fed by the IPA were analyzed in terms of size, location, and history of prior treatment.

RESULTS

In 14 (11%) of the 126 cases, the tumor was found to have a blood supply from an IPA. Eleven of these tumors were located in segments 2 and 7. Three tumors, which had not been treated previously, had a blood supply from an IPA. Six tumors were almost exclusively fed by an IPA and were located in segments 1, 1, and 4.

CONCLUSION

HCCs located in segments which form the bare area of the liver (S1, S2, S7) can be supplied by an IPA. This should be suspected when a lesion or part of a lesion is identified on contrast-enhanced CT but not on hepatic arteriography.

Effect of CYP2C19 polymorphism on the safety and efficacy of omeprazole in Japanese patients with recurrent reflux oesophagitis

BACKGROUND

The polymorphic enzyme cytochrome P450 2C19 affects omeprazole metabolism. This influence on metabolism might affect serum gastrin levels, and safety, during long-term treatment of reflux oesophagitis.

AIM

To examine the relationship between cytochrome P450 2C19 genotype and the safety profile of long-term omeprazole treatment.

METHODS

A total of 119 Japanese patients with recurrent reflux oesophagitis underwent cytochrome P450 2C19 genotyping prior to receiving daily omeprazole 10 mg or 20 mg for 6-12 months, during which adverse event frequency, serum gastrin levels and endoscopic findings were monitored.

RESULTS

The incidences of adverse events, serious adverse events and adverse events leading to withdrawal did not differ between homozygous extensive metabolizer (n = 46), heterozygous extensive metabolizer (n = 53) or poor metabolizer (n = 20) groups. In all genotype groups, serum gastrin increased during the first 3 months of dosing but stabilized thereafter. No significant differences were seen either in the rate of reflux oesophagitis healing or symptom improvement among genotype groups.

CONCLUSIONS

Long-term treatment with omeprazole was well-tolerated in Japanese patients, irrespective of their cytochrome P450 2C19 metabolic genotype, indicating that dose adjustment depending on metabolic genotype is not required during treatment with omeprazole.

FR146687, a novel steroid 5 alpha-reductase inhibitor: in vitro and in vivo effects on prostates

BACKGROUND

Steroid 5 alpha-reductase is implicated in the pathogenesis of benign prostatic hyperplasia (BPH). We studied the in vitro and in vivo effects of FR146687, a new inhibitor of 5 alpha-reductase.

METHODS

Two isozymes of rat and human 5 alpha-reductases were expressed in 293 cells. In vivo effects of drugs were evaluated on rat and dog prostates. Castrated immature rats were injected with testosterone propionate (TP) or 5 alpha-dihydrotestosterone propionate (DHTP) to induce growth of the ventral prostates. Testosterone and 5 alpha-dihydrotestosterone (DHT) contents in rat and dog prostates were measured by gas chromatography-mass spectrophotometry (GC-MS).

RESULTS

FR146687 showed noncompetitive inhibition in both isozymes and no inhibitory effects on other steroid oxidoreductases. In mature rats and castrated immature rats treated with TP, FR146687 dose-dependently reduced ventral prostate and seminal vesicle weight at doses above 0.1 mg/kg, while castrated immature rats treated with DHTP were not affected by FR146687. FR146687 showed more potent reduction of rat prostates than finasteride. DHT concentration in the prostates was significantly reduced when FR146687 was administered to rats and beagles.

CONCLUSIONS

FR146687 is a dual inhibitor for 5 alpha-reductase isozymes and significantly reduced the growth and DHT content in the prostate.

Synthesis of (+)- and (-)-nojirimycin and their 1-deoxy derivatives from myo-inositol

The conversion of the naturally abundant cyclitol, myo-inositol (4), into (+)-nojirimycin (1a), its enantiomer (1b), and their 1-deoxy analogues (2a and 2b) is described. Biological assay of 2a, 2b, and the bisulfite adducts of 1a and 1b (3a and 3b) showed that the compounds having the unnatural L-gluco configuration (2b and 3b) possess moderate-to-high inhibitory activity against almond beta-D-glucosidase and bovine liver beta-D-galactosidase.

Alternative promoters direct tissue-specific expression of the mouse protein phosphatase 2Cbeta gene

Type 2C protein phosphatases (PP2Cs), a class of ubiquitous and evolutionally conserved serine/threonine protein phosphatases, are encoded in at least four distinct genes and implicated in the regulation of various cellular functions. Of these four PP2C genes, the expression of the PP2Cbeta gene has been reported to be tissue-specific and development-dependent. To understand more precisely the regulatory mechanism of this expression, we have isolated and characterized overlapping mouse genomic lambda clones. A comparison of genomic sequences with PP2Cbeta cDNA sequences provided information on the structure and localization of intron/exon boundaries and indicated that PP2Cbeta isoforms with different 5' termini were generated by alternative splicing of its pre-mRNA. The 5'-flanking region of exon 1 had features characteristic of a housekeeping gene: it was GC-rich, lacked TATA boxes and CAAT boxes in the standard positions, and contained potential binding sites for the transcription factor SP1. In the 5'-flanking region of exon 2, several consensus sequences were found, such as a TATA-like sequence and negative regulatory element box-1, -2 and -3. Subsequent analysis by transient transfection assay with a reporter gene showed that these regions act as distinct promoters. Analysis of PP2Cbeta transcripts by reverse transcriptase-PCR showed that exon-1 transcripts were expressed ubiquitously in all of the tissues examined, whereas exon-2 transcripts were predominantly expressed in the testis, intestine and liver. These results suggest that the alternative usage of two promoters within the PP2Cbeta gene regulates tissue-specific expression of PP2Cbeta mRNA.

Differentiation-dependent enhanced expression of protein phosphatase 2Cbeta in germ cells of mouse seminiferous tubules

The presence of five distinct isoforms of protein phosphatase 2Cbeta (PP2Cbeta-1 approximately -5) is known. In this study, we demonstrate that the mRNA levels of PP2Cbeta-3, -4 and -5 and PP2Cbeta protein level increased during the course of the first wave of spermatogenesis in neonatal mouse testis. Northern blot and in situ hybridization analyses revealed that PP2Cbeta-3, -4 and -5 were expressed predominantly in pachytene spermatocytes and in more highly differentiated germ cells. The substrate specificity of PP2Cbeta-4 determined with artificial substrates differed from those of PP2Cbeta-3 and -5, suggesting that the difference in the structure of PP2Cbeta-3, -4 and -5 reflect their unique physiological functions in testicular germ cells.

Enhanced UV sensitivity of yeast cells induced by overexpression of Mg(2+)-dependent protein phosphatase alpha (type 2C alpha)

The UV sensitivity of wild-type Saccharomyces cerevisiae cells was increased 2-fold when rat Mg(2+)-dependent protein phosphatase alpha (protein phosphatase type 2C alpha) was overexpressed in the cells. The overexpression of this enzyme rendered the rad 18 mutant (defective in postreplication repair) more UV-sensitive than was observed in the wild-type cells. However, this increase in UV sensitivity disappeared when the host cells had a rad 1 mutation (defective in excision repair). These results suggest that the Mg(2+)-dependent protein phosphatase overexpressed in the yeast cells inhibited their excision repair system.