Biomedical subjects

Avi Orr-Urtreger

Publications and source records attributed to Avi Orr-Urtreger.

At least 19 recordsLinked to original sources

PubMed2007

The homozygous P582S mutation in the oxygen-dependent degradation domain of HIF-1 alpha is associated with increased risk for prostate cancer.

BACKGROUND: The heterodimeric transcription factor HIF-1 (hypoxia-inducible factor 1), consisting of a critically regulated HIF-1 alpha subunit and a constitutively expressed HIF-1 beta subunit, is a master regulator of genes involved in adaptation and survival under low-oxygen conditions. Increased levels of HIF-1 activity are associated with increased tumor aggressiveness, therapeutic resistance, and mortality. METHODS: We studied 402 prostate cancer patients for the presence of the 1772C > T (P582S) and 1790G > A (A588T) mutations within the oxygen-dependent domain of HIF-1 alpha. RESULTS: Homozygosity for the P582S mutation was fourfold greater among prostate cancer patients compared to controls (OR = 4.10 [C.I. 95% 1.11 < OR < 17.87], P = 0.018). The existence of this mutation in prostate cancer patients was not associated with any of the clinical or pathological characteristics of the disease. No significant differences were found between the frequencies of A588T mutation in prostate cancer patients and controls. CONCLUSIONS: Our data suggest that homozygous HIF1A P582S mutation confers significant susceptibility to prostate cancer.

Adult↗

PubMed2006

Differential brain transcriptome of beta4 nAChR subunit-deficient mice: is it the effect of the null mutation or the background strain?

Studies using mice with beta4 nicotinic acetylcholine receptor (nAChR) subunit deficiency (beta4-/- mice) helped reveal the roles of this subunit in bradycardiac response to vagal stimulation, nicotine-induced seizure activity and anxiety. To identify genes that might be related to beta4-containing nAChRs activity, we compared the mRNA expression profiles of brains from beta4-/- and wild-type mice using Affymetrix U74Av2 microarray. Seventy-seven genes significantly differentiated between these two experimental groups. Of them, the two most downregulated were spastic paraplegia 21 (human) homolog (Spg21) and 6-pyruvoyl-tetrahydropterin synthase (Pts) genes. Since the targeted mutagenesis of the beta4 nAChR subunit was done by using two mouse strains, 129SvEv and C57BL/6J, it is possible that the genes closely linked to the mutated beta4 gene represent the 129SvEv allele and not the control C57BL/6J-driven allele. We examined this possibility by using public database and quantitative RT-PCR. The expression levels of Spg21 and Pts genes that, like the beta4 gene, are localized on mouse chromosome 9, as well as the expression levels of other genes located on this chromosome, were dependent on the mouse background strain. The 67 differentially expressed genes that are not located on chromosome 9 were further analyzed for overrepresented functional annotations and transcription regulatory elements compared with the entire microarray. Genes encoding for proteins involved in tyrosine phosphatase activity, calcium ion binding, cell growth and/or maintenance, and chromosome organization were overrepresented. Our data enhance the understanding of the molecular interactions involved in the beta4 nAChR subunit function. They also emphasize the need for careful interpretation of expression microarray studies done on genetically manipulated animals.

Animals↗

PubMed2006

Array-based comparative genome hybridization in clinical genetics.

Abnormalities in DNA copy number are frequently found in patients with multiple anomaly syndromes and mental retardation. Array-based comparative genomic hybridization (array-CGH) is a high-resolution, whole-genome technology that improves detection of submicroscopic aberrations underlying these syndromes. Eight patients with mental disability, multiple congenital anomalies, and dysmorphic features were screened for submicroscopic chromosomal imbalances using the GenoSensor Array 300 Chip. Subtelomeric aberrations previously detected by fluorescence in situ hybridization (FISH) analysis were confirmed in two patients, and accurate diagnosis was provided in two previously undiagnosed complex cases. Microdeletions at 15q11.2-q13 in a newborn with hypotonia, cryptorchidism, and hypopigmentation were detected with few discrepancies between the array results and FISH analysis. Contiguous microdeletion of GSCL, HIRA and TBX1 genes at 22q11.2 was identified in a previously undiagnosed boy with an unusual presentation of the VCF/DiGeorge spectrum. In a newborn with aniridia, a borderline false-negative WT1 deletion was observed, most probably because of differences between the size of the genomic deletion and the microarray probe. A false-positive rate of 0.2% was calculated for clone-by-clone analysis, whereas the per patient false-positive rate was 20%. Array-CGH is a powerful tool for the rapid and accurate detection of genetic disorders associated with copy number abnormalities and can significantly improve clinical genetic diagnosis and care.

Abnormalities, Multiple↗

PubMed2006

Mutation screening and association study of the candidate prostate cancer susceptibility genes MSR1, PTEN, and KLF6.

BACKGROUND: MSR1, PTEN, and KLF6 have been implicated as candidate susceptibility genes for prostate tumorigenesis. METHODS: Three hundred Jewish prostate cancer patients were screened for alterations in these genes. RESULTS: MSR1 was conserved in all patients. PTEN screening revealed a novel missense mutation and a silent change. Five KLF6 alterations were detected in 17 patients, including Q160X, the only nonsense KLF6 germline mutation described to date in a cancer patient. The KLF6 IVS1-27G>A polymorphism, recently associated with prostate cancer risk, was detected in 11.9% of the patients and 17.3% of the controls (P = 0.043). IVS1-27A allele frequency was significantly lower in prostate cancer patients (P = 0.030), specifically in Ashkenazi patients (P = 0.047) compared to controls. CONCLUSIONS: We found no evidence that MSR1 and PTEN germline mutations are associated with prostate cancer risk in Jews. The negative association between KLF6 IVS1-27A and prostate cancer risk supports a population-specific effect of susceptibility alleles in prostate tumorigenesis.

Adult↗

PubMed2006

Familial clustering of site-specific cancer risks associated with BRCA1 and BRCA2 mutations in the Ashkenazi Jewish population.

Inherited mutations in BRCA1 and BRCA2 lead to significantly increased risks of breast and ovarian cancer. We used epidemiologic methods to evaluate the relative risks of breast cancer vs. ovarian cancer among women of Ashkenazi Jewish ancestry with inherited mutations in BRCA1 or BRCA2. The cancer of a family's index case (i.e., breast cancer vs. ovarian cancer) was significantly associated with site-specific risks of cancer in relatives known to carry mutations in BRCA1 or BRCA2. Specifically, breast cancer risks were higher among relatives of breast cancer index cases compared with relatives of ovarian cancer index cases [hazard ratio (HR) = 3.0, P < 0.001 for BRCA1 carriers and HR = 4.8, P = 0.017 for BRCA2 carriers], and ovarian cancer risks were higher among relatives of ovarian cancer index cases compared with relatives of breast cancer index cases (HR = 7.2, P = 0.001 for BRCA1 carriers and HR = 15.8, P = 0.018 for BRCA2 carriers). Breast and ovarian cancer risks also increased with more recent year of birth. For each later decade of birth, risk increased 1.2-fold (P = 0.03). Effects of cancer site of the index case and of birth cohort were independent. These results suggest that both genetic and nongenetic factors modify cancer risks among BRCA1 and BRCA2 mutation carriers, and that genetic modifiers and other familial factors may influence risk specifically for either breast or ovarian cancer.

Breast Neoplasms↗

PubMed2006

Cytogenetic analysis of sinonasal carcinomas.

BACKGROUND: Sinonasal carcinomas, including nonkeratinizing (NK) squamous cell carcinoma (SCC) and sinonasal undifferentiated carcinoma (SNUC), are uncommon malignant neoplasms arising from the Schneiderian respiratory epithelium of the nasal cavity and paranasal sinuses. Due to their low frequency, the cytogenetic data on these tumors is limited. METHODS: Seventeen patients who were operated on in our institution for extirpation of paranasal carcinomas were enrolled in this study. Fourteen pathologically confirmed samples of sinonasal carcinomas were cytogenetically analyzed using G-banding techniques after short-term culture. Three samples did not grow on culture. RESULTS: Five of the 14 sinonasal carcinomas had an abnormal karyotype (36%). Of the 9 NK SCCs, 3 had abnormal karyotypes with numerical and structural chromosomal anomalies. Of the 5 patients with SNUC, 2 had an abnormal karyotype. One case of SNUC had a diploid complex karyotype. Another case of SNUC had a near triploid composite karyotype with 60-69 chromosomes. The chromosome arms that involved frequent breakpoint and rearrangements were: 1p, 6p, 7p, and 12q. We found that 3 of the 3 patients who died of disease displayed an abnormal karyotype, whereas 2 of the 11 patients who are alive displayed an abnormal karyotype (P = 0.027). CONCLUSIONS: The study revealed that more than a third of the paranasal carcinomas carry an abnormal karyotype. No specific common aberrations were found in these tumors. To our knowledge this is the first attempt to investigate sinonasal squamous and undifferentiated carcinomas on a genetic level using G-banding technique. Additional studies are required in order to determine whether cytogenetic data may serve as an adjunct to conventional pathology for the diagnosis and prognosis assessment of these rare and highly aggressive tumors.

Adolescent↗

PubMed2006

An alternative spliced RNASEL variant in peripheral blood leukocytes.

2-5A-Dependent RNase L is an endoribonuclease that catalyzes RNA degradation and promotes apoptosis during the innate antiviral response in mammalian cells. Prior studies showed that RNASEL is widely expressed and suggested the presence of mRNA species of different sizes but lacked a characterization of these variants. Using RT-PCR, we show that RNASEL is expressed in all human tissues examined, whereas an alternatively generated spliced variant lacking the third exon (RNASEL del_Ex3) is solely expressed in peripheral blood leukocytes (PBL). Quantitative RT-PCR measurements of RNA from different PBL cell types separated by fluorescence activated cell sorting (FACS) showed that complete RNASEL mRNA levels were significantly elevated in granulocytes compared with all other PBL cell types, whereas expression was lowest in CD8(+) T cells. The alternatively spliced RNASEL del_Ex3 transcript was present in all PBL cell types examined but at lower levels than the full-length RNASEL mRNA. The presence of high levels of RNase L protein in granulocytes was confirmed by immunohistochemistry. Our findings are the first to demonstrate the presence of an alternatively spliced RNASEL mRNA and to demonstrate the variable expression of RNase L in different leukocytes. Our results suggest that RNase L plays an important role in granulocytes as an innate immunity enzyme that controls viral infections.

Alternative Splicing↗

PubMed2006

RNASEL mutation screening and association study in Ashkenazi and non-Ashkenazi prostate cancer patients.

Epidemiologic and genetic studies support the considerable effect of heritable factors on prostate tumorigenesis, although to date, no unequivocal susceptibility gene has been identified. The extensive study of RNASEL in prostate cancer patients worldwide has yielded conflicting results. We reevaluated the role of the RNASEL 471delAAAG Ashkenazi founder mutation in 1,642 Ashkenazi patients with prostate, bladder, breast/ovarian, and colon cancers; Ashkenazi controls; and in non-Ashkenazi prostate cancer patients and controls. The entire RNASEL coding sequence was also screened using denaturing high-performance liquid chromatography and multiplex ligation-dependent probe amplification for possible sequence variations or copy number changes in a population of prostate cancer patients. The 471delAAAG mutation was detected in 2.4% of the Ashkenazi prostate cancer patients; in 1.9% of patients with bladder, breast/ovarian, and colon cancers; and in 2.0% of the Ashkenazi controls. Seven additional variants were detected in RNASEL, including a novel potentially pathogenic splice site mutation, IVS5+1delG, although none were associated with increased prostate cancer risk. Multiplex ligation-dependent probe amplification analysis showed two RNASEL gene copies in all 300 prostate cancer patients tested. We estimated that the RNASEL 471delAAAG founder mutation, which was detected in 2% of the Ashkenazi Jews, originated between the 2nd and 5th centuries A.D., compared with the less frequent (1%) BRCA1 185delAG founder mutation, which originated hundreds of years earlier. Taken together, our analysis does not support a role for the RNASEL 471delAAAG Ashkenazi mutation nor for the other alterations detected in RNASEL in prostate cancer risk in Jewish men.

Adult↗

PubMed2006

Novel genes implicated in embryonal, alveolar, and pleomorphic rhabdomyosarcoma: a cytogenetic and molecular analysis of primary tumors.

Rhabdomyosarcoma, the most common pediatric soft tissue sarcoma, likely results from deregulation of the skeletal myogenesis program. Although associations between PAX3, PAX7, FOXO1A, and RMS tumorigenesis are well recognized, the entire spectrum of genetic factors underlying RMS development and progression is unclear. Using a combined approach of spectral karyotyping, array-based comparative genomic hybridization (CGH), and expression analysis, we examined 10 primary RMS tumors, including embryonal, alveolar, and the rare adult pleomorphic variant, to explore the involvement of different genes and genetic pathways in RMS tumorigenesis. A complete karyotype established for each tumor revealed a high aneuploidy level, mostly tetraploidy, with double minutes and additional structural aberrations. Quantitative expression analysis detected the overexpression of the AURKA gene in all tumors tested, suggesting a role for this mitotic regulator in the aneuploidy and chromosomal instability observed in RMS. Array-based CGH analysis in primary RMS tumors detected copy number changes of genes involved in multiple genetic pathways, including transcription factors such as MYC-related gene from lung cancer and the cytoskeleton and cell adhesion-encoding genes laminin gamma-2 and p21-activated kinase-1. Our data suggest the involvement of genes encoding cell adhesion, cytoskeletal signaling, and transcriptional and cell cycle components in RMS tumorigenesis.

Adolescent↗

PubMed2005

Increased severity of experimental colitis in alpha 5 nicotinic acetylcholine receptor subunit-deficient mice.

Substantial evidence suggests a negative association between cigarette smoking and the incidence and severity of ulcerative colitis, a common human inflammatory bowel disease. Nicotine has been implicated in this association. The detection of nicotinic acetylcholine receptors in colonic epithelium, the primary tissue affected in ulcerative colitis, suggests a role for these receptors in the beneficial effect of nicotine on colonic inflammation. Using an animal model, we demonstrate for the first time that alpha5 nicotinic acetylcholine receptor knockout mice have significantly more severe experimental colitis than wild-type controls and that nicotine significantly ameliorates its course when compared with wild-type controls. These findings suggest that alpha5-containing nicotinic acetylcholine receptors participate in the modulation of colitis in mice, but other nicotinic acetylcholine receptor subunits also mediate the antiinflammatory effects of nicotine.

Animals↗

PubMed2005

Lower core body temperature and attenuated nicotine-induced hypothermic response in mice lacking the beta4 neuronal nicotinic acetylcholine receptor subunit.

Diverse physiological and pathological effects of nicotine, including the alteration of body temperature, are presumably mediated by neuronal nicotinic acetylcholine receptors (nAChR). Previous studies have suggested the involvement of distinct nAChR subunits in nicotine-induced thermoregulation. We studied genetically manipulated knockout mice lacking the alpha7, alpha5 or beta4 subunit genes, in order to assess the effects of subunit deficiency on temperature regulation. Using a telemetry system, core body temperature was monitored continuously prior to and following nicotine administration in mutant mice and in wild-type littermates. Mice lacking in the beta4 nAChR subunit gene had significantly lower baseline core body temperature than all other mouse strains studied. beta4 null mice also demonstrated a reduced nicotine-induced hypothermic response and impaired desensitization following repeat nicotine exposure. These findings suggest the involvement of the beta4 nAChR subunit in both core body temperature homeostasis and nicotine-elicited thermo-alterations in mice.

Animals↗

PubMed2005

Hidden function of neuronal nicotinic acetylcholine receptor beta2 subunits in ganglionic transmission: comparison to alpha5 and beta4 subunits.

Neuronal nicotinic acetylcholine receptors (nAChR), which modulate fast excitatory postsynaptic potentials (f-EPSP), are located on both pre- and postganglionic sites in the autonomic nervous system (ANS). The receptor subunits alpha3, alpha5, alpha7, beta2 and beta4 are present in autonomic ganglia in various combinations and modulate acetylcholine (ACh) transmission. In the present study, autonomic functions were systemically examined in mice lacking beta2 subunits (beta2-/-) to further understand the functional role of beta2 subunits in modulating ganglionic transmission. The results show normal autonomic functions, both under physiological conditions and in perturbed conditions, on thermoregulation, pupillary size, heart rate responses and ileal contractile reactions. This suggests that the function of beta2-containing receptors in ganglionic transmission is hidden by the predominant beta4 containing receptors and confirms previous studies which suggest that alpha3alpha5beta4 nAChRs are sufficient for autonomic transmission. On the other hand, beta2-containing receptors have only a minor function on postsynaptic responses to ACh, but may modulate ACh release presynaptically, although there is no evidence for this.

Acetylcholine↗

PubMed2005

Initial experience of videocapsule endoscopy for diagnosing small-bowel tumors in patients with GI polyposis syndromes.

BACKGROUND: Small-bowel tumors frequently occur in familial adenomatous polyposis and other GI polyposis syndromes. These tumors are difficult to detect with conventional techniques. Our aim was to assess the utility of videocapsule endoscopy in the detection of small-bowel tumors in this setting. METHODS: We examined 19 familial adenomatous polyposis patients and 3 patients with either Peutz-Jeghers syndrome, hyperplastic polyposis, or Cowden disease. OBSERVATIONS: Prevalence of small-bowel polyps on videocapsule endoscopy was 59% in all patients, 52.6% in familial adenomatous polyposis patients, and 75% in a subgroup of familial adenomatous polyposis patients with exon 15 mutations. Videocapsule endoscopy was safe and well tolerated in all patients. CONCLUSIONS: Videocapsule endoscopy has a high yield in detecting small-bowel tumors in patients with GI polyposis syndromes. It may be especially indicated in familial adenomatous polyposis patients with the aggressive phenotype of the disease, e.g., mutations in exon 15.

Adenomatous Polyposis Coli↗

PubMed2004

Selective deletion of the alpha5 subunit differentially affects somatic-dendritic versus axonally targeted nicotinic ACh receptors in mouse.

We have compared the functional properties of nicotinic acetylcholine receptors (nAChRs) within both somatic and presynaptic domains of superior cervical ganglion (SCG) neurones from wild-type (WT) mice with those expressed by SCG neurones from mice with a targeted deletion of the gene for the alpha5-subunit. The functional profile of somatic nAChRs was assayed by direct macroscopic current recording and from measurements of nicotinic agonist-induced calcium transients with fura-2 imaging. The profile of nAChRs at presynaptic sites was assayed by measurement of nicotinic agonist-induced transmitter release (as preloaded [3H]noradrenaline) under conditions of action potential blockade. We have examined the responses to the nicotinic agonists acetylcholine, nicotine, cytisine, dimethylphenylpiperazinium iodide (DMPP) and epibatidine. Macroscopic current and calcium imaging assays revealed several differences in the functional profile of somatic nAChRs in WT SCG neurones compared with those from mice with the alpha5 subunit deleted. Somatic nAChRs in control animals were more potently activated by cytisine as compared to DMPP. In contrast, DMPP was consistently more potent than cytisine in mice lacking the alpha5 nAChR subunit. Differences in the somatic nAChR rank order of potency were most prominent after a least 1 day in vitro. The magnitude of somatic nAChR responses to nicotinic agonists was not substantially different in control mice compared with those of alpha5 subunit-deleted animals. Comparison of presynaptic nAChR-mediated responses in WT versus alpha5 subunit-deleted animals revealed a very different set of changes in the functional profile of prejunctional nAChRs compared with somatic nAChRs. In contrast to somatic nAChRs, the responses of prejunctional receptors were markedly enhanced in alpha5 knockout animals compared with control. Furthermore, all prejunctional receptor responses were most potently activated by DMPP in both control and in alpha5 subunit-deleted mice. Hence, the presence or absence of the alpha5 subunit did not affect the rank order of potency of agonists at preterminal sites but greatly affected the magnitude of presynaptic nAChR-mediated responses. The enhanced efficacy of nicotine at presynaptic receptors was corroborated in an acute atrium preparation from postnatal alpha5 subunit-deleted mice. These results confirm and significantly extend our previous observation that in the sympathetic nervous system, somatic and prejunctional receptors are different and rely on the presence of the alpha5 subunit in a distinct manner.

Animals↗

PubMed2004

Cytogenetic analysis of three variants of clival chordoma.

Chordoma is an uncommon malignant neoplasm derived from remnants of the embryonal notochord. The tumor arises in the sacrococcygeal region in most cases. Cytogenetic information on clival chordomas is scarce due to the low incidence of these tumors. In this study, we applied the G-banding and spectral karyotyping techniques to compare the karyotypes of three variants of clival chordoma: conventional, chondroid, and dedifferentiated. We describe a normal karyotype of a chondroid chordoma and a complex karyotype of a conventional chordoma involving chromosomes 1, 2, 3, 5, 8, 9, 11, 15, 19, 20, and X. The cytogenetic analysis of the dedifferentiated chordoma showed a polyploid complex karyotype of 71-123 chromosomes with double minutes that originated from chromosome 17.

Aged↗

PubMed2004

Nicotinic acetylcholine receptor alpha5 subunits modulate oxotremorine-induced salivation and tremor.

Neuronal nicotinic acetylcholine receptors (nAChRs) are composed of 12 subunits (alpha2-alpha10 and beta2-beta4). alpha5 Subunits, expressed throughout the central nervous system (CNS) and the autonomic nervous system (ANS), possess unique pharmacological properties. The effects of oxotremorine (OXO) on autonomic functions and tremor were examined in mice lacking alpha5 nAChR subunits (alpha5-/-) and compared with those in wild-type (WT) control mice. The alpha5-/- mice showed significantly increased salivation and tremor responses to OXO. The hypothermia, bradycardia and defecation induced by OXO were of similar magnitudes in the two mouse strains. The enhanced OXO effects in alpha5-/- mice indicate inhibitory effects of alpha5 subunits in autonomic ganglia, and support the participation of these subunits in cholinergic transmission in autonomic ganglia.

Acetylcholine↗

PubMed2004

Mice lacking neuronal nicotinic acetylcholine receptor beta4-subunit and mice lacking both alpha5- and beta4-subunits are highly resistant to nicotine-induced seizures.

Nicotine, the main addictive component of tobacco, evokes a wide range of dose-dependent behaviors in rodents, and when administrated in high doses, it can induce clonic-tonic seizures. Nicotine acts through the nicotinic acetylcholine receptors (nAChRs). Mutations in the human alpha4- and the beta2-nAChR subunit genes cause autosomal dominant nocturnal frontal lobe epilepsy. Using transgenic mice with mutations in nAChR subunits, it was demonstrated previously that the alpha4-, alpha5-, and alpha7-subunits are involved in nicotine-induced seizures. To examine the possibility that the beta4-subunit is also involved in this phenotype, we tested mice with homozygous beta4-subunit deficiency. The beta4 null mice were remarkably resistant to nicotine-induced seizures compared with wild-type and alpha5 null mice. We also generated mice with double deficiency of both alpha5- and beta4-nAChR subunits and demonstrated that they were more resistant to nicotine's convulsant effect than either the alpha5 or the beta4 single mutant mice. In addition, the single alpha5 mutants and the double alpha5beta4-deficient mice exhibited a significantly shorter latency time to seizure than that of the wild-type mice. Our results thus show that beta4-containing nAChRs have a crucial role in the pathogenesis of nicotine-induced seizures. Furthermore, by comparing multiple mutant mice with single and double subunit deficiency, we suggest that nicotinic receptors containing either alpha5- or beta4-subunits are involved in nicotine-induced seizures and that receptors containing both subunits are likely to contribute to this phenomena as well. However, the alpha5-subunit, but not the beta4-subunit, regulates the rate of response to high doses of nicotine.

Animals↗

PubMed2004

Synergistic control of keratinocyte adhesion through muscarinic and nicotinic acetylcholine receptor subtypes.

The biological mechanisms involved in initiating, coordinating, and ultimately terminating cell-cell adhesion in the stratified epithelium are not well understood at present. This study was designed to elucidate the roles of the muscarinic M3, the nicotinic alpha3, and the mixed muscarinic-nicotinic alpha9 acetylcholine receptors in physiologic control of keratinocyte adhesion. Both muscarinic and nicotinic antagonists caused keratinocyte detachment and reversibly increased the permeability of keratinocyte monolayers, indicative of the involvement of both muscarinic and nicotinic pathways in the cholinergic control of keratinocyte adhesion. Since phosphorylation of adhesion proteins plays an important role in rapid assembly and disassembly of intercellular junctions, we measured muscarinic and nicotinic effects on phosphorylation of keratinocyte adhesion molecules. The phosphorylation levels of E-cadherin, beta-catenin, and gamma-catenin increased following pharmacological blockage of muscarinic receptors. Long-term blocking of alpha3, alpha9, and M3 receptor signaling pathways with antisense oligonucleotides resulted in cell-cell detachment and changes in the expression levels of E-cadherin, beta-catenin, and gamma-catenin in cultured human keratinocytes. Simultaneous inhibition of several receptor subtypes with a mixture of antisense oligonucleotides produced intensified abnormalities with cell adhesion. Moreover, altered cell-cell adhesion was found in the stratified epithelium of alpha3, alpha9, and M3 receptor knockout mice. Keratinocytes from these mice exhibited abnormal expression of adhesion molecules at both the protein and the mRNA levels. Thus, our data indicate that the alpha3, alpha9, and M3 acetylcholine receptors play key roles in regulating in a synergistic mode keratinocyte adhesion, most probably by modulating cadherin and catenin levels and activities. These findings may aid in the development of novel methods useful for the treatment of skin adhesion diseases and tumor metastasis.

Animals↗