Administration of recombinant interleukin 12 prevents outgrowth of tumor cells metastasizing spontaneously to lung and lymph nodes

The present study investigates the ability of recombinant interleukin 12 (rIL-12) to modulate the growth of a primary tumor as well as the outgrowth of metastatic tumor cells in an ovarian carcinoma (OV-HM) model. This aggressive tumor displayed rapid growth of the primary tumor mass, high incidence of metastases to lung and lymph nodes, and invasion from the primary s.c. site to the peritoneal cavity. Starting 12 days after s.c. tumor cell implantation, several i.p. injections of rIL-12 at 2-3 day intervals resulted in regression of growing tumors. These treated mice did not show signs of metastases or tumor recurrence at the original site. One month after tumor implantation, untreated mice did not have visible lung metastasis, but some did have palpable lymph nodes. At this stage, the primary tumors of animals without palpable lymph nodes were surgically resected. When examined 2 months later, most animals had developed lymph node and lung metastases. In contrast, rIL-12 injections after tumor resection inhibited the development of metastases in both lung and lymph nodes. This contrasted with the failure of IL-2 to prevent metastases. Even for mice already showing signs of lymph node metastases or invasion of the abdominal wall, rIL-12 administration after tumor resection prevented further invasion to the peritoneal cavity and growth of metastatic tumor cells in lung. It was somewhat surprising that the IL-12 treatment of animals after 1 month of tumor growth without resection also resulted in complete tumor regression, as well as eradication of micrometastasis that would have occurred before the treatment. Moreover, they exhibited resistance to a rechallenge with the same tumor but not with a second tumor. Thus, this tumor system provides a relevant model to clinical situations in terms of treatment of advanced tumors and metastases. These results also indicate that IL-12 can induce a curative immune response, even in the face of an aggressive micrometastasizing tumor.

Inhibition of dextran and mutan synthesis by cycloisomaltooligosaccharides

Novel cyclic isomaltooligosaccharides, cyclodextran, strongly inhibited the dextransucrase reaction. The inhibition was dependent on the cyclodextran concentration and greatly enhanced by the first incubation at 30 degrees for 30 min. Cyclodextran-heptaose and -octaose were competitive inhibitors for sucrose yielding Ki's of 0.25 and 0.64 mM, respectively. Both reducing sugar and dextran producing activities of dextransucrase were almost equally inhibited by the cyclodextrans. Although gamma-cyclodextrin, palatinose, sucrose-monocaprate, and maltitol gave 5-35% inhibition, cyclodextran-heptaose gave 95% inhibition. Moreover, water-insoluble glucan (mutan) synthesis by the glucosyltransferase from Streptococcus mutans was significantly repressed by the addition of cyclodextran.

An unclassified cerebral small cell tumor in a patient with human T-cell lymphotropic virus type 1-induced primary extranodal lymphoma

We describe an autopsy case of a thalamic tumor in a patient with human T-cell lymphotropic virus type 1 (HTLV-1)-induced extranodal lymphoma of the skull. Neither brain tumors associated with adult T-cell leukemia nor HTLV-1-induced extranodal lymphoma of bone have previously been reported. The tumor, which resembled an oligodendroglioma or dysembryoplastic neuroepithelial tumor, was composed of medium-sized cells with dark, round-to-polygonal nuclei and a mucinous matrix that formed pericellular lakes. Tumor cells were immunoreactive with S-100 protein and neuron-specific enolase but not with glial fibrillary acid protein, synaptophysin, or vimentin. Tumor cells had prominent rough endoplasmic reticulum and free ribosomes with short processes, compatible with an oligodendroglial or small neuronal nature. Many atypical lymphocytes had infiltrated the leptomeningeal space, subependymal zone along the ventricular walls, fornices, corpus callosum, and right frontal lobe. Multinucleated or bizarre astrocytes and macrophages were found exclusively in the right frontal white matter. The coexistence of this unclassified peculiar brain tumor with bizarre astrocytosis suggests a cytopathic effect of HTLV-1 on human glioneuronal cells.

Effects of a selective endothelin A-receptor antagonist, BQ-123, in salt-loaded stroke-prone spontaneously hypertensive rats

1. We examined the effects of a selective endothelin A (ETA)-receptor antagonist, BQ-123, on the development of hypertension and organ damage in stroke-prone spontaneously hypertensive rats (SHRSP) given 1% NaCl for 6 weeks. 2. BQ-123 at doses of 0.7, 2.1 and 7.1 mg/day was continuously administered for 6 weeks to 8 week old salt-loaded SHRSP, who were given water containing 1% NaCl for the following 6 weeks, via a subcutaneous osmotic minipump. 3. Development of high blood pressure was accelerated in salt-loaded SHRSP compared with that in non-salt-loaded SHRSP. After 6 weeks of salt-loading, incidence of cerebral infarction, renal sclerosis and renal fibrosis were greater in salt-loaded than non-salt-loaded SHRSP. 4. BQ-123 attenuated the age-related rise in blood pressure in a dose-dependent manner. The effect coincided with reduction in the incidence of cerebral infarction and prevention of renal sclerosis and fibrosis. Kidney function was improved as observed by an increase in glomerular filtration rate and decreases in urinary protein excretion, blood urea nitrogen and fractional sodium excretion. Furthermore, BQ-123 prevented increases in the heart weight/bodyweight ratio and aortic wall thickness in salt-loaded SHRSP. 5. These results suggest that endogenous endothelin-1 (ET-1) and ETA-receptors may be, at least in part, involved in the pathogenesis of hypertension and organ damage in salt-loaded SHRSP.

Synthesis and antitumor activity of novel dolastatin 10 analogs

Dolastatin 10 (1) is a potent antineoplastic pentapeptide. Novel dolastatin 10 analogs each modified at one of the constituent amino acid derivatives, were synthesized and their antitumor activity was evaluated against P388 leukemia in mice. The structural requirements for antitumor activity are discussed. Some of the analogs, 31c, 35c, 38b, and 50c showed excellent activity in vivo. Highly active 50c, which lacks the thiazole group of 1, was selected for further development as an antitumor agent.

Type VI collagen periodic fibrils in the synovium of the mouse temporomandibular joint

Immunohistochemical staining with anti-type VI collagen antibody was strongly positive in the intimal layer and moderately positive in the subsynovium. After treatment with 20 mM ATP, numerous structures with a periodicity of 100 +/- 10 nm (type VI collagen fibrils) appeared around the synovial cells. As the periodic dark bands were stained by ruthenium red, proteoglycan(s) or glycosaminoglycan(s) were probably associated with the type VI collagen fibrils. When the tissue was digested with testicular hyaluronidase before ATP treatment, the periodic fibrils were not found, and only a filamentous network of 100-nm interval was seen around the cells. Thus, type VI collagen is abundant in the synovium of the mouse mandibular joint and is associated with proteoglycans or glycosaminoglycans, which might have a role in its formation.

Distribution and developmental changes in vasopressin V2 receptor mRNA in rat brain

The extrarenal presence of vasopressin V2 receptors (V2Rs) has been suggested but never been demonstrated. We investigated the distribution of V2R mRNA expression in the brain of newborn and adult rats using the reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization (ISH). RT-PCR assay revealed V2R mRNA in the cerebellum of both newborn and adult rats, and in the cerebrum of newborn but not adult rats. Further examination of the newborn rat brain by ISH showed dense localization of that V2R mRNA in the choroid plexus, and the neurons of the hippocampus and granular layer of the cerebellum. Epithelial cells and vascular endothelial cells were strongly stained in the choroid plexus. Moreover, expression of V2R mRNA in the hippocampus of the newborn rat decreased with age and could not be detected in rats more than 2 weeks old, while in the cerebellum V2R mRNA expression was stable and did not change with development. The results of our study have demonstrated the presence and distribution of V2R in the brain for the first time, and also show that expression of V2R mRNA in the hippocampus changes dynamically during the process of development. V2R may play an important role in the development of the central nervous system.

Two regions with differential growth-modulating activity in the N-terminal domain of ras GTPase-activating protein (p120GAP) src homology and Gly-Ala-Pro-rich regions

Ras GTPase-activating protein of 120 kDa (p120GAP) consists of a hydrophobic Gly-Ala-Pro-rich stretch and src homology 2 and 3 (SH2/SH3) domains in the N-terminal half, and a Ras GTPase-activating domain at the C-terminus. In order to evaluate the potential for cell-growth regulation of the N-terminal region of p120GAP, we isolated three distinct clones of rat 3Y1 fibroblast that express either the SH2/SH3 regions alone, the N-terminal half, or the whole p120GAP. Clones that express the SH2-SH3-SH2 regions of 37 kDa (p37SH2/3) at a level of only 15-30% that of endogenous p120GAP, but not clones expressing complete p120GAP or its N-terminal half of 55 kDa (p55GAP-N), showed significant growth-enhancing properties, including a higher saturation density and increased uptake of 2-deoxyglucose. Clones expressing p37SH2/3 or p55GAP-N maintained high levels of tyrosine-phosphorylated p190 and p62, both of which bind the SH2 domain of p120GAP, while clones expressing the whole p120GAP showed no tyrosine phosphorylation of p62. Furthermore, in the presence of a phorbol ester, only the clones expressing p37SH2/3 showed increased tyrosine phosphorylation of p62 and c-fos expression. These clones also showed the ability of colony formation in soft agar. These results indicate that the N-terminal domain of p120GAP consists of two regions with differential growth-enhancing activities and suggest that the transforming potential of SH2/SH3 regions is blocked by the N-terminal hydrophobic Gly-Ala-Pro stretch.

Comparison of the transport characteristics of ceftibuten in rat renal and intestinal brush-border membranes

The transport characteristics of ceftibuten, a dianionic cephem antibiotic, in rat renal and intestinal brush-border membranes were compared. Ceftibuten transport was mediated by two transport systems in the renal brush-border membrane and by one transport system in the intestinal brush-border membrane. The apparent kinetic parameters for the uptake of ceftibuten by the renal brush-border membrane vesicles, respectively, were: Km1, Km2 values of 26 and 1946 microM and Vmax1, Vmax2 values of 105 and 1400 pmol/mg protein per 30 s. The apparent kinetic parameters for the uptake by the intestinal brush-border membrane vesicles were: Km of 425 microM and Vmax of 1701 pmol/mg protein per 30 s. In the renal brush-border membrane, L-Ala-L-Pro was partially competitive and competitive inhibitor for the uptake by the high and low affinity systems, respectively. However, L-Ala-L-Pro was a non-competitive inhibitor for the uptake by the intestinal brush-border membrane vesicles. L-Carnosine was a specific and competitive inhibitor for the high affinity system in the renal brush-border membrane, while it had no effect on the low affinity system of the kidney or on the transport system of the intestine. It was concluded that the transport characteristics of ceftibuten in the renal and intestinal brush-border membranes are similar in some aspects but they are not identical.

[Pharmacokinetic and clinical studies with azithromycin (fine granule) in the pediatric field. Pediatric Study Group of Azithromycin]

Azithromycin (AZM) in 10% fine granules, a newly developed azalide antibiotic, was administered at a standard dose of 10 mg/kg once daily for 3 to 5 days (89.5% received 3 day administration) to children with infectious diseases and the efficacy and the safety of AZM were investigated. In addition AZM concentrations were determined in blood samples from 18 patients and in urine samples from 17 patients to examine o pharmacokinetic characteristics of AZM. 1. Absorption and excretion: Cmax's in 16 patients who received 10 mg/kg and 2 patients who received 20 mg/kg were 0.29 +/- 0.24 micrograms/ml and 0.75 micrograms/ml, respectively, while T 1/2's were 42.0 +/- 11.8 hours for the former and 51.3 hours for the latter. AUC(0 to approximately infinity)'s were 10.72 +/- 5.00 micrograms x hr/ml in the former and 28.83 micrograms x hr/ml in the latter. Urinary concentrations of AZM peaked at 48 to 72 hours after the administration of 10 mg/kg AZM in 14 patients, while it peaked at 24 to 48 hours in the patients who received 20 mg/kg. Urinary recovery rates in the first 120 hours after the start were 9.1 +/- 2.6% for 10 mg/kg and 10.8 +/- 3.4% for 20mg/kg. 2. Clinical efficacy: The study received 619 entries and 564 cases were evaluated for drug efficacy. The remaining were not evaluated because of dropout or exclusion. The efficacy rate, combining both "Excellent" and "Good" cases was 94.3% in 246 cases where pathogens were identified, classified as Group A. The efficacy rate was 90.7% for the remaining 321 cases, classified as Group B, where causative pathogens were unidentified. The difference between the two groups was no statistical significance. The combined efficacy rate was 92.2%. For the 116 cases where the patients had failed to respond to previous chemotherapies instituted for 3 days or longer, the efficacy rate for AZM was 94.0%. 3. Adverse reactions and abnormal laboratory tests: Incidents of diarrhea, soft stool, skin rashes, or vomiting were found in 15 patients (2.5%) of 596 cases eligible for evaluation. These reactions, however, were all transient and mild to moderate in severity in the 15 patients including 4 patients for whom the treatment was discontinued, all resolved in time. Abnormal changes in laboratory tests were found as follows: decrease in WBC in 23 patients (5.6%), increase in eosinophils in 28 (7.1%), increase in platelet count in 2 (0.5%), decrease in platelet count in 1 (0.3%), elevation of GOT in 3 (0.8%), and elevation of GPT in 6 (1.6%).(ABSTRACT TRUNCATED AT 400 WORDS)

Appendiceal intussusception due to an appendiceal malignant polyp--an association in a patient with Peutz-Jeghers syndrome: report of a case

A 40-year-old woman with Peutz-Jeghers syndrome and an appendiceal intussusception is reported. In this patient, the lead point was a large sessile, appendiceal polyp. The invaginated and inverted portion of the appendix resembled the long stalk of a pedunculated polyp on roentgenography and endoscopic examination. Histologically, the appendiceal polyp was a villous adenoma with mild to severe atypia and focal carcinoma in situ. In patients with Peutz-Jeghers syndrome, hamartomatous polyps and colorectal adenomatous polyps with highly malignant potential can coexist and must be managed appropriately. Therefore, when evaluating a polypoid or a pedunculated lesion in the cecal lumen, the possibility of an appendiceal intussusception should also be investigated.

[Transjugular intrahepatic portosystemic shunt for upper gastrointestinal bleeding due to portal hypertension: 2-year results]

We performed transjugular intrahepatic portosystemic shunt (TIPS) in 25 patients with liver cirrhosis who developed upper gastrointestinal bleeding due to portal hypertension. The procedure was successful in 23 patients, in whom portal pressure decreased by 51%. Bleeding was stopped in all 5 emergency for whom other treatments, including sclerotherapy, had failed. During the follow-up period (mean: 367 days), shunt dysfunction due to stenosis was observed in 75% of the patients. However, by percutaneous transluminal angioplasty, the patency could be maintained in 85% of the cases after 1 year and 73% of the cases after 2 years. Re-bleeding was observed in 13% of the cases after both 1 and 2 years. Color Doppler ultrasonography was useful for detecting shunt dysfunction. TIPS seems to be an effective treatment of upper gastrointestinal bleeding due to portal hypertension.

The intestinal transport mechanism of fluoroquinolones: inhibitory effect of ciprofloxacin, an enoxacin derivative, on the membrane potential-dependent uptake of enoxacin

PURPOSE

To clarify the absorption-structure relationship for the fluoroquinolones from the point of view of inhibitory behavior.

METHODS

The inhibitory effects of ciprofloxacin on the transport process of enoxacin across the rat intestinal brush-border membrane was examined.

RESULTS

Ciprofloxacin, which has a similar structure to enoxacin, exhibited a pH-dependent interference with enoxacin absorption from rat jejunal loops. The uptake experiments using BBM vesicles showed that ciprofloxacin significantly reduced not only the initial binding of enoxacin to the membrane surface, but also the K(+)- or H(+)-diffusion potential-dependent transport across the membrane. Furthermore, an H(+)-diffusion potential (interior negative) also exhibited a stimulative uptake of ciprofloxacin.

CONCLUSIONS

These results suggest that the inhibition behavior of ciprofloxacin from the jejunal loop was closely related to the ionic diffusion potential-dependent uptake of enoxacin across the brush-border membrane.

[Experimental and clinical study on intraoperative local infusion chemotherapy (ILIC) for advanced gastric carcinoma]

An intensive chemotherapy combined with surgery, termed "intraoperative local infusion chemotherapy (ILIC)", was devised. The ILIC procedure is to infuse 50 mg of cisplatin through the feeding artery to the tumor, which has been isolated from blood flow by clamping the stomach and blood vessels, before radical surgery. An experiment in dogs showed considerable free Pt transfer into thoracic lymph after ILIC. Sum total Pt in the thoracic lymph after ILIC (294.5 micrograms/3 h) was 4.3 times that after IV administration (68.3 micrograms/3 h). In ILIC, AUC of free Pt in the thoracic lymph was about 5.8 times that in peripheral blood. ILIC was applied in 24 advanced gastric cancer patients, consisting of 6, 2, 4 and 12 in pTNM stage II, IIIA, IIIB and IV, respectively. Pt concentration of the tissues was high in the tumor (23.22 micrograms/g) and the regional lymph nodes (2.95 micrograms/g) compared to that in the serum (0.45 microgram/ml). The survival rate (Kaplan-Meier) in the ILIC patients was significantly higher than that of control patients (matched pair method) from among patients treated by surgery alone. No fatal complications were encountered in any patient treated by ILIC.

Acute gastric mucosal lesions associated with cytomegalovirus infection in a non-immunocompromised host

A 75-year-old woman with epigastric pain and tarry stool was admitted to our hospital, where upper gastrointestinal endoscopic study revealed multiple gastric ulcers. The endoscopic biopsy specimens obtained on the seventh hospital day disclosed a few typical intranuclear cytomegalovirus inclusions. Cytomegalovirus-DNA was detected using polymerase chain reaction in a biopsy specimen. No immunologic abnormalities were demonstrated by any laboratory tests. While only a few cases of cytomegalovirus-associated gastric ulcer in non-immunocompromised hosts have been reported, this entity may be more frequently detected when careful histological examination is performed in the active stage rather than postponed until after healing of the ulcer.

Isolation of promoters from Brevibacterium flavum strain MJ233C and comparison of their gene expression levels in B. flavum and Escherichia coli

A promoter probe shuttle vector suitable for the isolation of promoter elements from coryneform bacteria was constructed. This vector carried the neomycin phosphotransferase (NPTII) gene from transposon Tn5 as a reporter gene, and was capable of replication in both Escherichia coli and Brevibacterium flavum. The vector was used in the construction of a B. flavum library of 899 independently isolated promoter clones. Promoters with a wide range of activities in B. flavum, including some very strong promoter elements, were isolated. Comparative analysis suggests that significant differences between B. flavum and E. coli may exist in the determinants of promoter strength.

Disruption of the function of tumor-suppressor gene p53 by the hepatitis B virus X protein and hepatocarcinogenesis

The X gene of the hepatitis B virus codes for a small basic protein and is able to transactivate viral and cellular genes, although the X protein exhibits no DNA-binding activity. The mechanism of transactivation by X protein has been suggested to be via protein-protein interaction(s). We first demonstrated that X protein had amino acid sequences homologous to the functionally essential domain of Kunitz-type serine protease inhibitors and that those sequences were indispensable for the transactivation function. We demonstrated that X protein exhibited an inhibitor activity against hepatic serine proteases, and subsequently found that the protein activated X gene transcription in HepG2 cells and that the X responsive element was localized in the minimal promoter of the X gene. In contrast, the tumor-suppressor gene p53, but not mutant p53, remarkably reduced transcription from the minimal promoter. This p53 repression on the X gene promoter was cancelled by X gene co-expression, probably indicating that the X protein disrupts the p53 tumor suppressor function in the nucleus. All data suggest that X protein leads to transactivation of cellular oncogenes by preventing an interaction between p53 and cellular transcription factor(s) consisting of the basal transcriptional machinery.

Management of gastric cancer patients with synchronous hepatic metastasis: a retrospective study

BACKGROUND/AIMS

In order to improve the management of patients of gastric cancer with synchronous hepatic metastasis, their records were retrospectively studied.

MATERIALS AND METHODS

From January 1981 to July 1993, 558 gastric cancer patients were admitted in our institute. Twenty-five with synchronous hepatic metastasis were used in this study. Among these 25 patients, six had hepatic metastasis alone and nineteen had some other additional noncurative prognostic factors. For the primary lesion, 12 patients received gastrectomy (total or distal subtotal) and 13 patients did not. For the hepatic metastasis, 12 patients had regional therapy (hepatectomy or hepatic arterial chemotherapy) and 13 had not. Both gastrectomy and regional therapy for hepatic metastasis were carried out in 6 patients who had hepatic metastasis alone.

RESULTS

Five year cumulative survival rate was 9%. Survival rate of patients with hepatic metastasis alone was significantly better than the patients with additional noncurative factors (p < 0.05). The two long term survivors in this study had no other noncurative factors except hepatic metastasis.

CONCLUSIONS

Neither gastrectomy nor regional therapy for hepatic metastasis had beneficial effects on the patients with additional noncurative factors. Gastrectomy and regional therapy for hepatic metastasis should be performed in patients without additional noncurative factors.

Unusual location of intracranial vagus neurinoma--case report

A 55-year-old male presented with hearing disturbance and tinnitus in the left ear. Computed tomography (CT) and magnetic resonance imaging demonstrated a well-defined, homogeneously enhanced mass in the left cerebellomedullary cistern without extension close to the jugular foramen. A three-dimensional image reconstructed from thin-slice CT scans demonstrated that the mass was clearly separated from the jugular foramen. The mass lesion was totally removed surgically. At surgery the tumor was found to originate from one rootlet of the vagal nerve just after its exit from the medulla oblongata. The histological diagnosis was neurinoma. Intracranial neurinomas of the glossopharyngeal, vagal, or accessory nerve usually originate within or close to the jugular foramen. This unusual location made it difficult to achieve a correct preoperative diagnosis.

[Postoperative adjuvant arterial infusion chemotherapy in patients with advanced hepatocellular carcinoma]

Seventy-five surgically treated patients with hepatocellular carcinoma (HCC) of Stage III or IV-A were divided into two groups: group I, control without postoperative adjuvant infusion (PAI); group II, patients treated with PAI. In the PAI group, 29 patients (mean diameter of tumors = 71 mm) prophylactically underwent PAI after hepatic resection. Chemotherapeutic agents, (5-FU, ADM, MMC, CDDP and Lipiodol) were administered 4 times a year via the hepatic artery through Infuse A port. The remaining 46 patients (mean diameter of tumors = 70 mm) served as the historical control without PAI. The 4-year cumulative survival rate was higher in the PAI group (45.6%) than in the control (25.4%, p = 0.0424). The 4-year disease-free survival rate was also improved in the PAI group (37.0%) compared with that in the control (14.4%, p = 0.0096). Intrahepatic multiple recurrence was recognized in 8 out of 29 patients in the PAI group (28%) and in 24 out of 46 in the control (53%, p = 0.036) within 1 year after surgery. Extrahepatic recurrence without diseases in the remnant liver tended to occur with higher frequency in the PAI group than in the control. Based on our data, we suggest that PAI is effective in alleviating intrahepatic multiple recurrence within 1 year after hepatic resection for advanced HCC and that systemic chemotherapy may be necessary for preventing extrahepatic recurrence.

[Usefulness of 3-dimensional image analysis of skull base lesions]

We have evaluated three-dimensional (3D) images of the skull base lesions for planning cranial base surgery. Fifty 3D images were reconstructed from computed tomographies (CT), and/or magnetic resonance (MR) images or MR angiographic images of 30 patients with skull base lesions. These images have provided useful information for pre-operative evaluation. The 3D image reconstructed from CT provides clear information concerning the bone. Conversely, the 3D image from MR images demonstrates soft tissue very clearly, and that from MR angiography provides a detailed description of the vasculature. For skull base lesions, it is essential to evaluate 3D images from the different modalities, especially CT scan and MR image.

No occurrence of DNA-polymerase Beta-gene mutation in human lung-carcinoma cell-lines with k-ras as, p53, or rb gene alterations

In order to investigate the relationship between a potential defect in the DNA repair system and human lung carcinogenesis, we examined the entire coding region of the human DNA polymerase beta gene using the reverse transcription-polymerase chain reaction (RT-PCR)/single-strand conformation polymorphism (SSCP) method in 31 human lung carcinoma cell lines (18 non-small cell lung carcinoma (NSCLC) cell lines and 13 small cell lung carcinoma (SCLC) cell lines, 4 cell lines with K-ras point mutation, 9 with p53 point mutation, 3 with retinoblastoma susceptibility (Rb) gene alteration). Mutation of the polymerase beta gene was undetectable in all of them. These results suggest that mutations of the DNA polymerae beta gene is extremely rare if it occurs at all in human lung cancer, and may have no relation with K-ras, p53, or Rb gene alterations.

Improved total synthesis and structure-activity relationship of arenastatin A, a potent cytotoxic spongean depsipeptide

An efficient asymmetric synthesis of a cyclic depsipeptide arenastatis A (1) is described. 1, isolated from the marine sponge Dysidea arenaria, exhibited extremely potent cytotoxicity with IC50 of pg/ml for KB cells, and in this context the structure-activity relationship among several stereoisomers of 1 and allied compounds has also been examined.

Phylogenetic relationship of silkmoths inferred from sequence data of the arylphorin gene

A portion of the arylphorin gene from 11 silkmoth species belonging to the families Saturniidae and Bombycidae was amplified by a polymerase chain reaction. Approximately 460 bp corresponding to the third exon, the third intron, and the fourth exon were successfully amplified, sequenced, and compared. Sequences corresponding to the third and fourth exons were the most conserved, whereas sequences corresponding to the third intron were conserved only between species belonging to the same genus. We also analyzed differences of substitution rates among codon positions and between synonymous and nonsynonymous sites. Phylogenetic trees were constructed using the entire nucleotide sequences, the first and second codon positions, nonsynonymous sites, transversions, and the inferred amino acid sequences in the exons by the neighbor-joining method. These trees supported the monophyly of the families Saturniidae and Bombycidae as well as the monophyly of the genera Actias, Bombyx, Antheraea, and Samia.