Anti-tumor immunity induced by OK-432-derived DNA

We have tried to identify the effective components of OK-432, a Streptococcus-derived anti-cancer immunotherapeutic agent. In the current study, we investigated the effect of OK-432-derived DNA (OK-DNA) in augmenting anti-cancer immune response. Analysis of OK-DNA with the restriction enzymes Hpa II and Msp I revealed that OK-DNA contained unmethylated CpG motifs. OK-DNA induced Th1-type cytokines, such as IFN-gamma and IL-12, and augmented killer cell activities in vitro on human peripheral blood mononuclear cells, whereas the methylated OK-DNA did not. Cytokines were also produced by OK-DNA-stimulated splenocytes derived from wild-type mice but not from TLR9-deficient mice. In the in vivo study, a peritumoral administration of OK-DNA resulted in a significant inhibition of tumor growth in syngeneic tumor-bearing wild-type and TLR4-deficient mice but not in TLR9-deficient mice. Anti-tumor effect of OK-432 in TLR9-deficient mice was significantly but partially reduced as compared with that in wild-type mice, while the effect of OK-432 was almost completely eliminated in TLR4-deficient mice. These findings suggest that unmethylated CpG-DNA in OK-432 functions as an active component in OK-432-induced anti-cancer immunity via TLR9, at least in part.     

Cryotherapy of the resection edge after hepatectomy of colorectal liver metastases

Obtaining a one-centimeter negative margin is an important factor in preventing disease recurrence after surgery for hepatic tumors. Cryotherapy of the resected edge has been used to achieve optimal margin clearance in cases in which the alternative would be an extended high-risk liver resection. As a concrete method, cryotherapy was delivered with a liquid nitrogen based compact system (CRY-AC, Brymill Co., USA). The resection edge with involved or inadequate resection margins was ablated directly by using the flat probe for 3 minutes per 1 place. Between 2002 and present, a total of 14 patients with colorectal liver metastases underwent edge cryotherapy. Although there was no hemorrhage from the stump, postoperative leak of the bile and stump recurrence were recognized in each patient. Since cryotherapy has features that make the vascular difficult to be damaged, the complication was not recognized in the patient with exposed vascular in the resected edge. By extending the follow-up period, we want to examine whether the edge recurrence could be controlled or not.     

Vasculitic condition following instillation of epirubicin hydrochloride in an outpatient chemotherapy

The appearance of vasculitis is often observed following the use of epirubicin hydrochloride in outpatients. As it is important to continue to provide a safe treatment for outpatient with little or no side effects, the aim of this study was to reveal causes underlying the outbreak of vasculitis or the vasculitic state of patients who had undergone instillation of epirubicin hydrochloride as an adjuvant therapy following a breast cancer surgery. The study was conducted based on past investigation records. We extracted relevant factors such as age, previous illness, physical condition and dosage of epirubicin hydrochloride from past records which may all be connected to the outbreak of vasculitis. We administered one dose of epirubicin hydrochloride that was diluted into 50-100 ml of normal saline solution or 5% glucose and instilled over a period of 30 minutes. As a result of this instillation of epirubicin hydrochloride, 35 out of 45 cases displayed vasculitis. We did not observe any relationship among the aged (over 60), previous illness or physical condition (BMI over 25) and the appearance of vasculitis. When a dosage amount of more than 110 mg of epirubicin hydrochloride was administered, 23 out of 29 cases displayed vasculitis. From the past records, it was observed that the cause of vasculitis was dependent on the administrative method itself. As previous studies reported that vasculitis was low when epirubicin hydrochloride was retained in blood vessels for only a short time, our study, however, concentrated on how to administer epirubicin hydrochloride. Our results suggested that an adoption of a single dosage system may suppress the outbreak of vasculitis.     

A case of stage IV gastric cancer previously treated with TS-1 completely responding to second-line chemotherapy with weekly paclitaxel therapy

We report herein a case with stage IV gastric cancer previously treated with TS-1 completely responding to second-line chemotherapy with weekly paclitaxel therapy. A 65-year-old female was diagnosed as having type 3 gastric cancer with para-aortic lymph node metastases. She underwent total gastrectomy with extended lymph node dissection on March 2003. Histopathological examination revealed that the tumor was poorly-differentiated adenocarcinoma with para-aortic lymph nodes metastases and completely resected.After the operation,she was treated by adjuvant chemotherapy with TS-1. In March of 2004, she suffered from hematuria, and a CT scan revealed para-aortic lymph nodes metastases and left kidney metastasis. Then, she was treated by a weekly infusion of paclitaxel as second-line chemotherapy. After 3 courses, the tumor disappeared and efficacy was judged as CR. Moreover, CR was maintained after 7 courses. At this writing in January of 2005, she is well and has been treated with paclitaxel without any severe adverse events. Therefore, weekly paclitaxel therapy was considered to be one of the promising second-line chemotherapies for advanced or recurrent gastric cancer previously treated by TS-1.     

Overexpression of Aurora-A potentiates HRAS-mediated oncogenic transformation and is implicated in oral carcinogenesis

Aurora kinases are known to play a key role in maintaining mitotic fidelity, and overexpression of aurora kinases has been noted in various tumors. Overexpression of aurora kinase activity is thought to promote cancer development through a loss of centrosome or chromosome number integrity. Here we observed augmentation of G12V-mutated HRAS-induced neoplastic transformation in BALB/c 3T3 A31-1-1 cells transfected with Aurora-A. Aurora-A-short hairpin RNA (shRNA) experiments showed that the expression level of Aurora-A determines susceptibility to transformation. Aurora-A gene amplification was noted in human patients with tongue or gingival squamous carcinoma (4/11). Amplification was observed even in pathologically normal epithelial tissue taken at sites distant from the tumors in two patients with tongue cancer. However, overexpression of Aurora-A mRNA was observed only within the tumors of all patients examined (11/11). Our data indicate that Aurora-A gene amplification and overexpression play a role in human carcinogenesis, largely due to the effect of Aurora-A on oncogenic cell growth, rather than a loss of maintenance of centrosomal or chromosomal integrity.     

Genetic variations and haplotypes of UGT1A4 in a Japanese population

Nineteen genetic variations, including 11 novel ones, were found in exon 1 and its flanking region of the UDP-glucuronosyltransferase (UGT) 1A4 gene from 256 Japanese subjects, consisting of 60 healthy volunteers, 88 cancer patients and 108 arrhythmic patients. These variations include -217T>G and -36G>A in the 5'-flanking region, 30G>A (P10P), 127delA (43fsX22; frame-shift from codon 43 resulting in the termination at the 22nd codon, codon 65), 175delG (59fsX6), 271C>T (R91C), 325A>G (R109G), and 357T>C (N119N) in exon 1, and IVS1+1G>T, IVS1+98A>G and IVS1+101G>T in the following intron. Among them, 127delA and 175delG can confer early termination of translation, resulting in an immature protein that probably lacks enzymatic activity. Variation IVS1+1G>T is located at a splice donor site and thus may lead to aberrant splicing. Since we did not find any significant differences in the frequencies of all the variations among the three subject groups, the data were analyzed as one group. The allele frequencies of the novel variations were 0.006 for IVS1+101G>T, 0.004 for 30G>A (P10P) and 357T>C (N119N), and 0.002 for the 8 other variations. In addition, the two known nonsynonymous single nucleotide polymorphisms (SNPs), 31C>T (R11W) and 142T>G (L48V), were found at 0.012 and 0.129 frequencies, respectively. The SNP 70C>A (P24T), mostly linked with 142T>G (L48V) in German Caucasians, was not detected in this study. Sixteen haplotypes were identified or inferred, and some haplotypes were confirmed by cloning and sequencing. It was shown that most of 142T>G (L48V) was linked with -219C>T, -163G>A, 448T>C (L150L), 804G>A (P268P), and IVS1+43C>T, comprising haplotype *3a; haplotype *4a harbors 31C>T (R11W); 127delA (43fsX22) and 142T>G (L48V) were linked (haplotype *5a); 175delG (59fsX6) was linked with 325A>G (R109G) (*6a haplotype); and -219C>T, -163G>A, 142T>G (L48V), 271C>T (R91C), 448T>C (L150L), 804G>A (P268P), and IVS1+43C>T comprised haplotype *7a. Our results provide fundamental and useful information for genotyping UGT1A4 in the Japanese and probably Asian populations.     

Inhibitory effect of thiopental on ultra-rapid delayed rectifier K+ current in H9c2 cells

Using the whole-cell voltage clamp technique, we investigated the effects of thiopental on membrane currents in H9c2 cells, a cell line derived from embryonic rat heart. Thiopental blocked a rapidly activating, very slowly-inactivating ultra-rapid type I(Kur)-like outward K(+) current in a concentration-dependent manner. The half-maximal concentration (IC(50)) of thiopental was 97 microM with a Hill coefficient of 1.2. The thiopental-sensitive current was also blocked by high concentrations of nifedipine (IC(50) = 9.1 microM) and 100 microM chromanol 293B, a blocker of slowly activating delayed rectifier K+ current (I(Ks)), but was insensitive to E-4031, an inhibitor of rapidly activating delayed rectifier K(+) current (I(Kr)). TEA (tetraethylammonium) at 5 mM and 4-AP (4-aminopiridine) at 1 mM reduced the K(+) current to 30.8 +/- 12.2% and 20.5 +/- 6.5% of the control, respectively. Using RT-PCR, we detected mRNAs of Kv2.1, Kv3.4, Kv4.1, and Kv4.3 in H9c2 cells. Among those, Kv2.1 and Kv3.4 have I(Kur)-type kinetics and are therefore candidates for thiopental-sensitive K(+) channels in H9c2 cells. This is the first report showing that thiopental inhibits I(Kur). This effect of thiopental may be involved in its reported prolongation of cardiac action potentials.     

Estimation of detection limit from slope of B/B0 in competitive ELISA

A method has been proposed for determining the detection limit (L(D)) from the slope of a semilogarithmic plot of a B/B(0) curve in competitive enzyme linked immunosorbent assay (ELISA). As an application, this paper describes a graphic determination of L(D) from analogue data in the literature. The L(D) obtained corresponds to the concentration at which the relative standard deviation of concentration estimates is 30%.     

Centrally mediated antihyperalgesic and antiallodynic effects of zonisamide following partial nerve injury in the mouse

Some antiepileptic drugs are used clinically to relieve neuropathic pain. We have evaluated the effects and investigated the possible mechanisms of action of zonisamide, an antiepileptic drug, on thermal hyperalgesia and tactile allodynia in a murine chronic pain model that was prepared by partial ligation of the sciatic nerve. Subcutaneously administered zonisamide (10 and 30 mg/kg) produced antihyperalgesic and antiallodynic effects in a dose-dependent manner; these effects were manifested by elevation of the withdrawal threshold in response to a thermal (plantar test) or mechanical (von Frey) stimulus, respectively. Similar analgesic effects were obtained in both the plantar and von Frey tests when zonisamide was injected either intracerebroventricularly (i.c.v., 10 and 30 μg) or intrathecally (i.t., 10 and 30 μg). It is thought that this elevation of the thermal and mechanical withdrawal thresholds after local injection of zonisamide is not generated secondarily via impaired motor activity, since zonisamide (30 μg, i.c.v. or i.t.) did not affect locomotor activity, as assessed in sciatic-nerve-ligated mice. Moreover, the nitric oxide synthase inhibitor L-NAME, when injected either i.c.v. or i.t., potentiated the analgesic effects of zonisamide. In contrast, neither i.c.v. nor i.t. zonisamide produced antinociceptive effects against acute thermal and mechanical nociception in non-ligated mice. Together, following peripheral nerve injury, it appears that zonisamide produces centrally mediated antihyperalgesic and antiallodynic effects partly via the blockade of nitric oxide synthesis.