Gastric hyposecretion in esophageal squamous-cell carcinomas

Recently, gastric fundic atrophy is reported to be an independent risk factor for esophageal squamous-cell carcinoma (ESCC). The aim of this study is to investigate the acid secretory level in ESCC in a case-control study. From April 2004 to March 2008, 100 consecutive subjects with early ESCC and 100 age- and sex-matched asymptomatic controls were prospectively enrolled. Gastrin-stimulated acid output was assessed by endoscopic gastrin test. Conditional regression analyses were used to adjust for other potential confounders. Multivariate analyses revealed a strong association between profound hypochlorhydria and ESCC with odds ratio (95% confidence interval): 6.0 (1.9-18.4). The association remained significant after adjusting for the effect of gastric atrophy as a covariate. The association became stronger as the ESCC developed more distal site of the esophagus. This study indicates that profound hypochlorhydria is a strong independent risk factor for ESCC even after adjusting for the influence of gastric atrophy.

Development of a laser-focused ion beam combination machine

We have developed a laser and focused ion beam (FIB) compound system to process an optical component device with an ultrafine precision minute surface structure and a micromedical device. This machine consists of an FIB and three types of lasers with an atomic force microscope. This system can fabricate decamicrometer area by laser and submicrometer area by FIB at one chuck. When processing the press mold die of a microlens array (10x10) in a glasslike carbon with a femtosecond laser, a diameter of 3.2 microm and depth of 0.43 microm are obtained. However, the surface roughness is more than Rz=0.5 microm. After this process, we finished this surface with the use of the FIB. As a result, the surface roughness is less than Rz=0.05 microm.

Introduction of transformed chloroplasts from tobacco into petunia by asymmetric cell fusion

Plastid engineering technique has been established only in Nicotiana tabacum, and the widespread application is severely limited so far. In order to exploit a method to transfer the genetically transformed plastomes already obtained in tobacco into other plant species, somatic cell fusion was conducted between a plastome transformant of tobacco and a cultivar of petunia (Petunia hybrida). A tobacco strain whose plastids had been transformed with aadA (a streptomycin/spectinomycin adenylyltransferase gene) and mdar [a gene for monodehydroascorbate reductase (MDAR)] and a petunia variety, 'Telstar', were used as cell fusion partners. An efficient regeneration system from the protoplasts of both the parents, and effectiveness of selection for the aadA gene with spectinomycin were established before the cell fusion. In addition, the influence of UV irradiation on the callus development from the protoplasts and shoot regeneration of tobacco was investigated. Protoplasts were cultured after cell fusion treatment with polyethylene glycol, and asymmetric somatic cybrids were selected using the aadA gene as a marker. Although many shoots of tobacco that had escaped the UV irradiation regenerated, several shoots possessing the morphology of petunia and the resistance to spectinomycin were obtained. Molecular analyses of the petunia type regenerants demonstrated that they had the nuclear and mitochondrial genomes derived from petunia besides the chloroplasts of tobacco transformed with aadA and mdar. Furthermore, it was ascertained that mdar was transcribed in the somatic cybrids. The results indicate the success in intergeneric transfer of transformed plastids of tobacco into petunia.

A novel Rf gene controlling fertility restoration of Ogura male sterility by RNA processing of orf138 found in Japanese wild radish and its STS markers

To reveal the molecular and genetic mechanism of fertility restoration in Ogura male sterility in Japanese wild radish (Raphanus sativus var. hortensis f. raphanistroides), we investigated fertility restoration of a plant that lacks the dominant type of orf687, a previously identified fertility restorer gene. A total of 100 F2 plants were made from the cross between a male-sterile strain with the Ogura cytoplasm, 'MS-Gensuke', and a Japanese wild radish plant. Segregation of pollen fertility in the F2 plants led us to assume that 2 dominant complementary genes controlled the fertility restoration of the plants. However, the fertility of 27 of 59 male-fertile plants was not completely restored, resulting in a group of plants with partial male fertility. Northern blot analysis of the CMS-associated gene orf138 indicated that one restorer allele (termed Rft) was involved in the processing of orf138 RNA. Rapid amplification of cDNA ends (RACE) and subsequent Northern blot analysis confirmed that the orf138 transcript lost a 5' part of the coding region of the orf138 gene in the restored plants. The accumulation of ORF138 protein was significantly reduced by Rft, but trace amounts of the protein were recognized in both partially male-fertile and male-sterile plants with Rft. The relationship of pollen fertility and segregation of co-dominant sequence tagged site (STS) markers in the F2 generation suggested that the penetrance of Rft was so low that Rft needs suitable conditions to function sufficiently for the complete restoration of fertility.

[How to tell a patient the truth?--a case report from a psycho-oncology outpatient clinic]

Depression and anxiety are common psychiatric syndromes in the cancer population, but are not always managed very well due to the barriers to psychiatric consultation in Japan. We have tried to care for cancer patients with depression or anxiety through our psycho-oncology outpatient clinic. We have found that some anxiety in cancer patients derives from miscommunications between patients and physicians in charge because physicians do not tell the conditions of diseases clearly to patients. Needless to say, physicians should learn the communication skills regarding breaking bad news but we would like to emphasize the importance of smooth communication among health care professionals through this case report which makes us reconsider how we should have told the patient the truth (the time for stopping anti-cancer treatment, prognosis and so on) to a patient.

Involvement of REG Ialpha protein in the regeneration of ductal epithelial cells in the minor salivary glands of patients with Sjögren's syndrome

The regenerating gene (Reg) was originally isolated from regenerating rat pancreatic islets and revealed recently to constitute a multi-gene family in humans. REG Ialpha protein is known to be overexpressed not only in various human inflammatory diseases but also in various experimental models of inflammation in animal tissues. However, its involvement in pathophysiology of the minor salivary gland (MSG) is not clear. We investigated REG Ialpha expression in the MSG of patients with primary Sjögren's syndrome (SS) and assessed its role in ductal epithelial cell proliferation in such tissues. Lip biopsy specimens were obtained from 40 patients with primary SS and examined using immunohistochemistry for REG Ialpha protein, Ki67 and single-strand DNA (ssDNA). The relationships among clinicopathological factors and expression of REG Ialpha protein, Ki67 and ssDNA in the MSG were then analysed. REG Ialpha protein was expressed rarely in ductal epithelial cells of the normal MSG but was apparently overexpressed in those of patients with SS. The labelling indices for both Ki67 and ssDNA in the ductal cells of the MSGs were significantly higher in SS patients than in controls. Moreover, these labelling indices were significantly higher in REG Ialpha-positive than in negative SS patients. REG Ialpha protein may play a role in the regeneration of ductal epithelial cells in the MSGs of patients with SS.

Establishment of a tetraploid Meth-A cell line through polyploidization by demecolcine but not by staurosporine, K-252A and paclitaxel

Polyploid cells are made by DNA reduplication without cell division, however, it is not easy to establish polyploid mammalian cell lines. It is worth studying the difference in cell character between hyperploid and parent cell lines. Meth-A cells were polyploidized by demecolcine, K-252a, staurosporine and paclitaxel. The cell-cycle responses of highly polyploid Meth-A cells after the removal of the drugs were examined by flow cytometry (FCM). Meth-A cells were highly polyploidized by these drugs. The polyploid Meth-A cells gradually decreased in ploidy after the drug release. A tetraploid Meth-A cell line was established only from the demecolcine-induced polyploid Meth-A cells. The duration of G1, S and G2/M phases of the tetraploid cell line were mostly the same as those of the parent diploid cells, except that the G2/M phase was 1.5 h longer. The chromosome number of tetraploid Meth-A cell line was about twice of the diploidy. A tetraploid Meth-A cell line was established.

Inhibition of chalcone synthase expression in anthers of Raphanus sativus with Ogura male sterile cytoplasm

BACKGROUND AND AIMS

Expression of the mitochondrial gene orf138 causes Ogura cytoplasmic male sterility (CMS) in Raphanus sativus, but little is known about the mechanism by which CMS takes place. A preliminary microarray experiment revealed that several nuclear genes concerned with flavonoid biosynthesis were inhibited in the male-sterile phenotype. In particular, a gene for one of the key enzymes for flavonoid biosynthesis, chalcone synthase (CHS), was strongly inhibited. A few reports have suggested that the inhibition of CHS causes nuclear-dependent male sterile expression; however, there do not appear to be any reports elucidating the effect of CHS on CMS expression. In this study, the expression patterns of the early genes in the flavonoid biosynthesis pathway, including CHS, were investigated in normal and male-sterile lines.

METHODS

In order to determine the aberrant stage for CMS expression, the characteristics of male-sterile anthers are observed using light and transmission electron microscopy for several stages of flower buds. The expression of CHS and the other flavonoid biosynthetic genes in the anthers were compared between normal and male-sterile types using real time RT-PCR.

KEY RESULTS

Among the flavonoid biosynthetic genes analysed, the expression of CHS was strongly inhibited in the later stages of anther development in sterility cytoplasm; accumulation of putative naringenin derivatives was also inhibited.

CONCLUSIONS

These results show that flavonoids play an important role in the development of functional pollen, not only in nuclear-dependent male sterility, but also in CMS.

Overexpression of RegIV in peritoneal dissemination of gastric cancer and its potential as A novel marker for the detection of peritoneal micrometastasis

BACKGROUND

Regenerating gene type IV (RegIV) is a candidate marker for cancer and inflammatory bowel disease. In this study, its potential as a novel marker for the detection of gastric cancer peritoneal micrometastases was examined.

PATIENTS AND METHODS

RegIV mRNA levels in the peritoneal washes of 95 gastric cancer patients and 22 with benign disease were quantified by real-time RT-PCR. To examine whether expression of RegIV enhance tumorigenicity or not, thirty two mice were injected intraperitoneally or subcutaneously with RegIV transfectants of TMK-1 cells, parental TMK-1 cells, or neomycin control transfectants.

RESULTS

RegIV expression was markedly higher in patients with peritoneal metastases compared to those without. The level of RegIV mRNA in gastric cancer patients was related to the extent of wall penetration. A cut-off value for RegIV-positive expression was based on an analysis of negative control patients with benign disease, and gastric cancer patients above the cut-off value constituted the micrometastasis (MM+) group. Based on this criteria, 3 out of 43 T1 or T2 cases were MM+ (93% specificity). Among 15 patients with peritoneal dissemination (7 out of 15 cases were positive by cytology), 14 cases were positive for RegIV expression (93% sensitivity), while analysis of carcinoembryonic antigen (CEA) mRNA failed to detect micrometastases in 4 cases (73% sensitivity). Combined analysis of CEA and RegIV improved the accuracy of diagnosis to 100%. The prognosis of RegIV-positive cases was significantly worse than that of RegIV-negative cases. Multivariate analysis using the Cox proportional hazards model suggested that RegIV may be an independent prognostic factor. Stable expression of RegIV significantly enhanced peritoneal metastasis in an animal model of gastric cancer.

CONCLUSION

These findings suggest that RegIV mRNA expression has the potential to serve as a novel marker for detecting peritoneal dissemination in gastric cancer.

Lack of synchrony among multiple nuclei induces partial DNA fragmentation in V79 cells polyploidized by demecolcine

The nuclear morphology of polyploidized cells was examined in V79 Chinese hamster cells polyploidized by demecolcine or K-252a, inhibitors of spindle fibre formation and protein kinases, respectively. A variety of nuclear morphologies, including multinuclei, were observed in V79 cells polyploidized by demecolcine but not by K-252a, which produced mononuclear cells. A lack of synchrony in the nuclear cycle was observed among nuclei in multinuclear polyploidized cells. Partial DNA fragmentation, defined as DNA fragmentation of a nucleus in a multinuclear cell, was detected using the TUNEL method in V79 cells polyploidized by demecolcine but not by K-252a. Apoptosis occurred earlier in cell populations treated with demecolcine than in these treated with K-252a once the drugs were removed from the medium, suggesting that polyploidized cells with separate nuclei tend to apoptose earlier than those with mononuclei.

Establishment of a tetraploid cell line from mouse H-1 (ES) cells highly polyploidized with demecolcine

OBJECTIVE

Establishment of tetraploid ES cells.

MATERIALS AND METHODS

Mouse H-1 (ES) cells were polyploidized by demecolcine and released from the drug.

RESULTS

A tetraploid cell line (4nH1 cells) was established from mouse H-1 (ES) cells (2nH1 cells) highly polyploidized by treatment with demecolcine. Cell cycle parameters of 4nH1 cells were almost the same as those of 2nH1 cells, suggesting that the rate of DNA synthesis was about twice that of the diploid cells. Mode of chromosome number of 4nH1 cells was 76, about twice that of 2nH1 cells. Cell volume of 4nH1 cells was about twice of that of diploid cells, indicating that 4nH1 cells contained about twice as much total intracellular material as 2nH1 cells. Morphology of the 4nH1 cells was flagstone-like, thus differing from that of the spindle-shaped 2nH1 cells, suggesting that the transformation had occurred during the diploid-tetraploid transition. 4nH1 cells exhibited alkaline phosphatase activity and formed teratocarcinomas, implying that they would be pluripotent.

CONCLUSION

A pluripotent tetraploid cell line (4nH1 cells) was established.

Frequent silencing of RUNX3 in esophageal squamous cell carcinomas is associated with radioresistance and poor prognosis

Radiotherapy is an effective treatment for some esophageal cancers, but the molecular mechanisms of radiosensitivity remain unknown. RUNX3, a novel tumor suppressor of gastric cancer, functions in transforming growth factor (TGF)-beta-dependent apoptosis. We obtained paired samples from 62 patients with advanced esophageal cancers diagnosed initially as T3 or T4 with image diagnosis; one sample was obtained from a biopsy before presurgical radiotherapy, and the other was resected in surgical specimens after radiotherapy. RUNX3 was repressed in 67.7% cases of the pretreatment biopsy samples and 96.7% cases of the irradiated, resected samples. The nuclear expression of RUNX3 was associated with radiosensitivity and a better prognosis than cytoplasmic or no RUNX3 expression (P<0.003); cytoplasmic RUNX3 expression was strictly associated with radioresistance. RUNX3 was downregulated and its promoter was hypermethylated in all radioresistant esophageal cancer cell lines examined. Stable transfection of esophageal cancer cells with RUNX3 slightly inhibited cell proliferation in vitro, enhanced the antiproliferative and apoptotic effects of TGF-beta and increased radiosensitivity in conjunction with Bim induction. In contrast, transfection of RUNX3-expressing cells with a RUNX3 antisense construct or a Bim-specific small interfering RNA induced radioresistance. Treatment with 5-aza-2'-deoxycytidine restored RUNX3 expression, increased radiosensitivity and induced Bim in both control and radioresistant cells. These results suggest that RUNX3 silencing promotes radioresistance in esophageal cancers. Examination of RUNX3 expression in pretreatment specimens may predict radiosensitivity, and induction of RUNX3 expression may increase tumor radiosensitivity.

Developmental Changes in Heart Photosensitivity of the Isopod Crustacean Ligia exotica

During juvenile development, the cardiac pacemaker of the isopod crustacean Ligia exotica is transferred from the myocardium to the cardiac ganglion of the neurogenic heart. In adult, light stimulus decreases the beat frequency of the heart. To elucidate developmental changes in the photosensitivity of the juvenile Ligia heart, we examined the effect of a light stimulus on the semi-isolated heart of juveniles at various developmental stages by the recording membrane potential of the myocardium. We also examined the effect of hyperpolarizing current injection into the myocardium, because this causes different effects on the beat frequency between myogenic and neurogenic hearts. In newly hatched juveniles, beat frequency decreased upon current injection but exhibited no response to white light. In contrast, 10 days after hatching, beat frequency did not change upon current injection, but decreased in response to white light. The heart photoresponse of juveniles was reversibly eliminated by application of tetrodotoxin, which changes the heartbeat from neurogenic to myogenic by suppressing cardiac ganglion activity. The proportion of juveniles exhibiting a heart photoresponse increased gradually up to 100% during the period between 3 and 10 days after hatching. The results suggest that the heart photoresponse of L. exotica appears in association with transfer of the cardiac pacemaker from the myocardium to the cardiac ganglion during juvenile development.

Non-cavernomatous superior mesenteric thrombosis successfully recanalized with interventional radiological procedures carried out with a combination transmesenteric and transjugular approaches

This is the study of a 52-year-old man with oesophageal, rectal and anal varices caused by portal hypertension with complete obstruction of the superior mesenteric vein. Treatment by two sessions of interventional radiological procedures was successful. The first was a catheter-directed thrombolysis using the transmesenteric approach. The second was percutaneous transluminal angioplasty and stent implantation for the obstructed segment of the superior mesenteric vein and the creation of a transjugular intrahepatic portosystemic shunt. In the second session, devices were advanced over a guidewire inserted from the right jugular vein and pulled out of the ileocolic vein using the pull-through technique.

1173C>T polymorphism in VKORC1 modulates the required warfarin dose

The response to warfarin is highly variable among individuals and such variability is likely to have some genetic basis. We evaluted the effect of VKORC1 polymorphisms on warfarin response among Japanese, taking advantage of its unique population structure in which CYP2C9 *2 and *3 alleles are relatively rare. Thirty-one patients (12-34 years old; median, 22) on warfarin were recruited from a pediatric cardiology clinic. Genotyping of the C>T polymorphism at position 1173 in intron 1 of VKORC1 revealed that 26 patients (84%) were T/T homozygotes at nucleotide 1173, whereas 5 (16%) were C/T heterozygotes. Complete linkage disequilibrium was observed between the 1173C > T polymorphism and another polymorphism, the 3730G > A, in the 3' untranslated region. The C/T heterozyogtes at the 1173C > T polymorphism tended to require more warfarin than the T/T homozygotes, when adjusted for international normalized ratio (p = 0.003). Both the 1173C > T polymorphism and the 3730G > A polymorphism are likely to be inert from a functional standpoint. Rather, based on the complete linkage disequilibrium between 1173C > T and 3730G > A polymorphisms, we suspect that the actual change that defines the relative resistance to warfarin may be present in the proximity of these two polymorphisms.

Photosensitive neurogenic heart of the isopod crustacean Ligia exotica

The heart of animals is regulated through the central nervous system in response to external sensory stimuli. We found, however, that the adult neurogenic heart of the isopod crustacean Ligia exotica has photosensitivity. The beat frequency of the isolated heart decreased in response to a light stimulus. Magnitude of the response was stimulus intensity dependent and the heartbeat frequency decreased to less than 80% of the dark value during illumination of the white light with an intensity of 6.0 mW cm-2. The spectral sensitivity curve of the heart photoresponse peaked at a wavelength around 520 nm. In response to 530 nm monochromatic light, the relationship between light intensity and response magnitude was linear and the threshold intensity was 7.26 x 1012 quanta cm-2 s-1. Bursting activity of the cardiac ganglion, which is located in the heart and acts as the cardiac pacemaker deceased in frequency in response to illumination by white light. This fact suggests that the heart photoresponse of L. exotica results from the photosensitivity of the cardiac ganglion neurons. The photoresponse of the heart therefore contributes to regulation of cardiac output in addition to other regulatory systems.

Phase II study of a combination of S-1 and weekly paclitaxel in patient with advanced or recurrent gastric cancer

14033

Background: Based on the results of our phase I study on a combination of S-1 (tegafur, oxonic acid, and CDHP) and weekly paclitaxel (PTX) for advanced or recurrent gastric cancer (ARGC) (Ueda et al, ASCO 2004), we conducted a multi-center phase II study to prospectively evaluate efficacy, QOL, and toxicity of S-1 plus weekly PTX in patients with ARGC. Methods: Eligibility included patients with histologically-proven ARGC, 20–80 years old, having a ECOG performance status (PS) of 0–2 and adequate organ functions, and having received no prior chemotherapy except postoperative adjuvant therapies without taxanes. S-1 was given orally at a dose of 80 mg/m2/day for 14 consecutive days (days 1–14) followed by a 2-week rest. PTX was administered weekly as a 1-hour intravenous infusion on days 1, 8, and 15. This treatment was repeated every 4-weeks as one cycle. Results: Fifty-four patients with measurable lesions (RECIST) were enrolled between Feb. 2004 and Nov. 2005. Histologically, a half of the patients had differentiated type and the other patients had undifferentiated type adenocarcinoma. The median age was 61 (range, 38–78). Three-fourths were male patients. The PS was 0/1/2 in 47/6/1 patients respectively. Thirty nine were primary cases and 15 were recurrent cases after gastrectomy. Treatment was terminated in two patients for toxicities and in one patient for refusal during the first cycle; thus compliance of 94.4%. A total of 254 cycles were administered (median 4.7, range 2–14), and 45 patients were assessable efficacy and toxicity until Dec. 2005. In these 45 assessable patients, 2 CRs and 27 PRs were obtained, resulting in an overall response rate of 64.4%. Twelve pts (26.7%) had stable disease, and 4 pts (8.9%) progressed. The tumor control rate was 91.1%. Conclusions: The combination of S-1 and weekly PTX is highly active for ARGC, and can be given safely with good tolerance and convenience profile. It is a candidate for the standard regimen and expected to contribute to better prognosis and QOL in ARGC patients.

No significant financial relationships to disclose.

Monoclonal antibody A7-superparamagnetic iron oxide as contrast agent of MR imaging of rectal carcinoma

Superparamagnetic iron oxide (SPIO)-based colloid has been used clinically as a tissue-specific magnetic resonance contrast agent. We coupled monoclonal antibody A7 (Mab A7), which reacts specifically with human colorectal carcinoma, to Ferumoxides (SPIO) and examined the accumulation of this conjugate in xenografted tumours in nude mice. We examined in vitro immunoreactivity of Mab A7 coupled to Ferumoxides and its in vivo distribution in nude mice with human colorectal carcinoma. Magnetic resonance imaging of tumour-bearing nude mice was performed 72 h after injection of A7-Ferumoxides. A7-Ferumoxides retained binding activities that were nearly identical to intact Mab A7. More of the radiolabelled A7-Ferumoxides accumulated in the tumour than normal mouse IgG-Ferumoxides from 12 h onwards after injection (P<0.05). Both A7-Ferumoxides and normal mouse IgG-Ferumoxides disappeared from blood linearly over time. The accumulation levels in normal tissue decreased linearly over time but were lower than levels in tumours from 6 h. In magnetic resonance T2-weighted imaging of the tumour-bearing nude mice, signal intensity was reduced at the margin of the tumour by injection of A7-Ferumoxides. Mab A7 coupled to Ferumoxides is potentially suitable as a magnetic resonance contrast agent for detecting local recurrence of rectal carcinoma.