34 These authors contributed equally to the work.Key Words: CD38, oxytocin, mutation, polymorphism, autism, high-functioning autism Author information Correspondence and requests for materials should be addressed to H. Higashida (haruhiro@med.kanazawa-u.ac.jp). 3 ABSTRACTThe neurobiological basis of autism spectrum disorder (ASD) remains poorly understood.Given the role of CD38 in social recognition through oxytocin (OT) release, we hypothesized that CD38 may play a role in the etiology of ASD. Here, we first examined the immunohistochemical expression of CD38 in the hypothalamus of post-mortem brains of non-ASD subjects and found that CD38 was colocalized with OT in secretory neurons.In studies of the association between CD38 and autism, we analyzed 10 single nucleotide polymorphisms (SNPs) and mutations of CD38 by re-sequencing DNAs mainly from a case-control study in Japan, and Caucasian cases mainly recruited to the Autism Genetic Resource Exchange (AGRE). The SNPs of CD38, rs6449197 (p<0.040) and rs3796863 (p<0.005) showed significant associations with a subset of ASD (IQ>70; designated as high-functioning autism (HFA)) in the U.S. 104 AGRE family trios, but not with Japanese 188 HFA subjects. A mutation that caused tryptophan to replace arginine at amino acid residue 140 (R140W; (rs1800561, 4693C>T)) was found in 0.6%-4.6% of the Japanese population and was associated with ASD in the smaller case-control study. The SNP was clustered in pedigrees in which the fathers and brothers of T-allele-carrier probands had ASD or ASD traits. In this cohort OT plasma levels were lower in subjects with the T allele than in those without. One proband with the T allele who was taking nasal OT spray showed relief of symptoms. The two variant CD38 poloymorphysms tested may be of interest with regard of the pathophysiology of ASD.4

Blocking monoclonal antibodies (mAbs) specific to mouse interleukin-1 receptor antagonist (IL-1ra) were prepared by immunizing Armenian hamsters with recombinant mouse IL-1ra. A sensitive and specific ELISA against mouse IL-1ra was also established. In Propionibacterium acnes-induced liver injury, P. acnes induced transient increase of serum tumor necrosis factor-alpha levels but not those of IL-1ra, IL-1, and IL-6. However, subsequent lipopolysaccharide (LPS) challenge induced the increase of serum levels of all these cytokines and the peak serum IL-1ra level was more than 20 times as high as serum IL-1 levels. Immunohistochemical analysis demonstrated that IL-1ra was predominantly produced by hepatocytes during the course of the priming phase by P. acnes and eliciting phase by LPS challenge. Furthermore, the administration of a mAb to mouse IL-1ra exacerbates the liver injury induced by P. acnes and sublethal dose of LPS, suggesting a protective role of endogenous IL-1ra in this liver injury model.

Our previous study in extramammary Paget's disease showed neither p53 mutations nor allelic loss at selected loci implicated in other cancers, suggesting a pathogenesis of this skin cancer different from other common epithelial malignancies. To examine further the genetic defects in extramammary Paget's disease, we carried out molecular genetic analyses in 31 tumor samples obtained from 27 cases of extramammary Paget's disease without underlying malignancies. Immunohistochemistry using CB-11 monoclonal antibody revealed either membrane or cytoplasmic erbB-2 oncoprotein overexpression in none of the 13 primary in situ tumors, but in one recurrent in situ tumor, 10 of 13 invasive primary tumors and two of four lymph node metastases. Sensitive dual color fluorescence in situ hybridization analysis using probes for erbB-2 gene locus and chromosome 17 pericentromere, however, revealed different erbB-2 gene status in the erbB-2 overexpressing tumors. One recurrent in situ tumor and one lymph node metastasis showed definite gene amplification characterized by multiple scattered signals or a few large clustered erbB-2 signals, whereas four tumors with predominantly cytoplasmic erbB-2 overexpression were thought to have low-grade gene amplification. The remaining six tumors overexpressing erbB-2 showed no increase of erbB-2 copy numbers. No evidence of abnormal activation of the beta-catenin gene, a critical mediator of Wnt signaling pathway, in any tumor by immunohistochemical staining and by direct sequencing and reverse transcription-polymerase chain reaction analysis was found. Frequent overexpression of erbB-2 by either gene amplification or possible transcriptional activation in invasive primary tumors and metastases suggests an important part for this oncogene in the progression of extramammary Paget's disease.

The relation between expression of cell cycle-regulator molecules and apoptosis was examined in surgical specimens and cultured human lung carcinoma cell lines. Cell-cycle regulation, a fundamental mechanism determining cell proliferation, is precisely regulated by the specific interaction of cyclins, cdks and cdk-inhibitors. 1,2 Aberrant expression of cyclins and cdks is involved in oncogenic transformation in cultured cells. 3,4 Successive clinicopathologic analyses of human malignant tumors, including carcinomas of the breast, lung, gastrointestinal tract, ovary and other sites, showed a correlation between overexpression of cell-cycle proteins and worse clinical outcome. [5][6][7][8][9] Indeed, in previous studies of human lung carcinomas and soft tissue sarcomas, we found that the expression and kinase activity of the cyclin A/cdk2 complex were novel predictors of proliferative activity and prognosis. 6,10,11 Thus, studies in both cultured cells and human tumors have consistently suggested that dysregulated expression of cyclin/cdk complexes is crucially involved in neoplastic transformation and the aggressive phenotypes of cancers.However, in the past decade, overexpression or abnormal expression of several positive regulators of the cell cycle has been closely associated with apoptosis. These proteins include c-myc, E2F1 and the HPV oncoproteins. 12-15 Several studies have implicated cell-cycle regulator molecules in apoptosis: e.g., upregulation of cyclin D1, cdk4 and/or cdc2 may be a critical event during apoptosis in neuronal cells. 16 -18 Furthermore, several reports have implicated other cell cycle-regulatory molecules, including cyclin E and cyclin B, as key factors in the apoptosis of cultured cells. 19,20 Although these reports suggested that overexpression of any cyclin or cdk could induce apoptosis, each has been shown to have individual potential functions. Previously, we demonstrated that (i) constitutive overexpression of cdk4 significantly promotes apoptosis in rat pheochromocytoma PC12 cells; 17 (ii) in contrast, constitutive overexpression of cdk2 or cdc2 promotes cell proliferation and abrogates the response to nerve growth factor; 4,21 and (iii) transient overexpression of cdk4 or cyclin D1 induces apoptosis in the presence of trophic support in neuronal, hematopoietic and human cancer cell lines. 22,23 These results overall suggest that cdk4/cyclin D1 kinase plays a specific and crucial role in inducing apoptosis in a wide spectrum of cell types. However, observations of these phenomena have been limited to cultured cells and precise pathobiologic or clinicopathologic analyses on apoptosis in surgical specimens of human tumors have not been documented. Several clinicopathologic analyses of apoptosis have examined its prognostic significance in human cancers but with somewhat mixed results. In lung carcinomas, several groups have reported that enhanced apoptosis is associated with shortened survival, 24,25 yet other studies have found no statistically significant correlation. 26 In cont...

Over the past few decades, remarkable advances have been achieved in cancer therapy, including chemotherapeutic agents, their mode of application and more broader therapeutic strategies. Promising new therapeutic targets have emerged in the past ten years as a result of recent advances in our understanding of the pathobiology of malignant cells, in particular, regarding functions of suppressor oncogene products. Among them, the agents that alter the cell cycle have recently been of particular interest, since cell cycle regulation is basic mechanism underlying cell fate, i.e., proliferation, differentiation or death. Furthermore, the human genome project has made possible the future development of so-called "tailor-made medicine", i.e. the design of appropriate drugs for specific genetic profiles and application of drugs that are tailored to each tumor and patient. In this article, we will introduce and discuss recent progress in the development of agents that influence the cell cycle and their future potential in cancer therapy from three standpoints with our own experimental works; i) the inhibition of cell proliferation and/or induction of differentiation by cyclin-dependent kinase (cdk)-inhibitor, e.g. olomoucin, butyrolactone-I, ii) induction of apoptosis by directing "abortive cell cycle", or the transient upregulation of cdk activity, e.g. flavopiridol, and iii) countering the development of drug resistance by adjunctive administration of cdk-inhibitors with conventional anti-cancer drug, e.g., p21-gene transfer with cisplatin. Conclusively none of these three approaches by itself is satisfactory, and that the effective cancer therapies will require the administration of several agents and/or methods under the design of their synergistic effects.