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101.
Takashi Ueno Akira Tangoku Shigefumi Yoshino Toshihiro Abe Hideto Hayashi Hiroaki Toshimitsu Kiichiro Hashimoto Tomomitsu Satoh Atsunori Oga Tomoko Furuya Masaaki Oka Kohsuke Sasaki 《Clinical cancer research》2003,9(14):5137-5141
PURPOSE: Selection of appropriate protocols for treatment of superficial esophageal squamous cell carcinoma (SESCC) is dependent on lymph node metastasis status. Therefore, it is important to know whether lymph node metastasis is present before treatment. EXPERIMENTAL DESIGN: In this study, we examined the relation between DNA sequence copy number aberrations detected by comparative genomic hybridization and lymph node metastasis in 26 surgically resected SESCCs (training samples). We then assessed whether the genetic information is predictive for nodal status in biopsy specimens from eight newly enrolled patients with SESCC (blinded samples). RESULTS: Pathological examination revealed that 17 of 26 training samples (65.4%) did not have associated lymph node metastasis. Gains of 8q24 and/or 20q12-qter were observed in 12, including all (nine of nine) with nodal metastasis. Fourteen training samples did not have gain of either 8q24 or 20q12-qter. Of the blinded samples, two showed no gain of 8q24 or 20q12-qter, and as anticipated the postoperative pathological examination revealed no nodal metastasis. The remaining six blinded samples had gains of 8q24 and/or 20q12-qter, and lymph node metastasis was detected by postoperative examination in four of these tumors. CONCLUSIONS: Absence of gains of 8q24 and/or 20q12-qter appears to be associated with absence of lymph node metastasis in patients with SESCC; therefore, less invasive surgery can be chosen. 相似文献
102.
Kawanishi M; Kohno T; Otsuka T; Adachi J; Sone S; Noguchi M; Hirohashi S; Yokota J 《Carcinogenesis》1997,18(11):2057-2062
Allelotype and replication error (RER) phenotype analyses were performed to
clarify the pathogenetic significance of inactivation of tumor suppressor
genes and genomic instability in the genesis and progression of small cell
lung carcinoma (SCLC). We examined 37 cases of SCLC for loss of
heterozygosity (LOH) and microsatellite instability at 49 loci on all 39
nonacrocentric chromosomal arms. LOH was frequently (>70%) detected on
chromosomes 3p (29/32, 90.6%), 5q (15/21, 71.4%), 13q (25/26, 96.2%), 17p
(22/25, 88.0%), and 22q (24/33, 72.7%). Frequent LOH (>70%) on these
loci was observed even among seven cases of stage I tumors. The incidence
of LOH on all 39 nonacrocentric chromosomal arms was not significantly
different between primary tumors and metastases. These results suggest that
inactivation of multiple tumor suppressor genes accumulates relatively
early during progression of SCLC and it may be responsible for clinically
and biologically aggressive phenotype of SCLC. RER was observed in 6/37
(16.2%) of SCLC, however, RER at multiple loci was observed only in two
cases. Therefore, it was indicated that genomic instability is uncommon,
but might play a role in the genesis of a small subset of SCLC.
相似文献
103.
CD44 is a cell surface glycoprotein with a number of isoforms generated by alternative splicing of ten 'variant' exons in humans. Variant exon 6-containing isoforms of CD44 (CD44v6) have been implicated in the metastatic potential of rat carcinoma cell lines. Human homologues of CD44v6 are expressed in several tumour types and are involved in their progression. In the present study, we examined the expression of CD44 mRNA in 20 acute myelocytic leukemias by semiquantitative RT-PCR analysis and assessed its prognostic value. In all leukemic cells the predominant isoform was the 'standard' form of CD44 (CD44H), and intense bands were found in eight cases. CD44v6 was expressed in 11 cases, although its levels and those of other variants containing exon v7 through to v10 were much lower than those of CD44H. Isoforms containing exon v4 or v5 could not be detected. The expression of CD44v6 correlated with the death rate from leukemia (p > 0.05), but was not related to other risk factors. On the other hand, the intense expression of CD44H did not correlate with the prognosis of leukemia. CD44v6 thus appears to be a marker for the poor prognosis of acute myelocytic leukemia. 相似文献
104.
RER phenotype and its associated mutations in familial gastric cancer 总被引:11,自引:1,他引:11
To clarify the genetic background of gastric cancer, we collected 28
familial gastric cancers (FGCs) with reference to the Amsterdam criteria in
hereditary non-polyposis colorectal cancer (HNPCC) and investigated the
frequency of replication error (RER) at six microsatellite loci and
frameshift mutations in its related genes in these tumors. RER was detected
in seven (25%) of the 28 gastric cancers. Five (18%) cases showed RER at
more than two loci. The apparent increased incidence of RER in FGC was not
detected compared with that reported in sporadic gastric cancers
previously. Among four cases with RER at more than three loci, frameshift
mutations in the (A)8 track of the hMSH3 gene were detected in all the four
cases and mutations in the (A)10 track of the transforming growth
factor-beta type II receptor (TGF-beta RII) gene were detected in the three
of them. Histologically, three of the four cases were of the intestinal
type, and the other one was the diffuse type. No mutation was detected in
the (C)8 and (GT)3 tracks of the hMSH6 and TGF-beta RII genes respectively.
These results indicate that the acquisition of the RER phenotype equally
influences the gastric carcinogenesis of both sporadic and familial cases,
and that the majority of FGC is pathogenetically distinct from HNPCC.
相似文献
105.
Infrequent Mutations of the hOGG1 Gene, That Is Involved in the Excision of 8-Hydroxyguanine in Damaged DNA, in Human Gastric Cancer 总被引:4,自引:0,他引:4
Kazuya Shinmura Takashi Kohno Hiroshi Kasai Kenji Koda Haruhiko Sugimura Jun Yokota 《Cancer science》1998,89(8):825-828
DNA glycosylase, encoded by the hOGG1 gene, repairs 8-hydroxyguanine (oh8 Gua), which is an oxidatively damaged mutagenic base. To clarify whether the DNA repair activity of hOGG1 protein is involved in gastric carcinogenesis, we examined 9 gastric cancer cell lines and 35 primary gastric cancers for mutations and genetic polymorphisms of the hOGG1 gene by polymerase chain reaction-single strand conformation polymorphism analysis. A G-to-A transition was detected in a gastric cancer cell line, MKN1. This nucleotide change caused the conversion of the amino acid from Arg to His at codon 154, which is located in a domain highly conserved among human, mouse, and yeast OGG1 proteins. No mutation was detected in primary gastric cancers. We compared the distribution of the polymorphic alleles associated with enzymatic activity (hOGG1-Ser326 vs. hOGG1-Cys326 ) between 35 gastric cancer patients and 42 healthy individuals. Although the frequency of the Cys326 allele, associated with low enzymatic activity, in gastric cancer patients was a little higher than that in healthy individuals, the difference did not reach statistical significance. These results suggest that low hOGG1 activity due to mutations and genetic polymorphisms is involved in the development of only a small subset of gastric cancers. 相似文献
106.
Monosynaptic and disynaptic projections from the substantia nigra pars reticulata to the parafascicular thalamic nucleus in the rat 总被引:1,自引:0,他引:1
We examined a direct pathway and an indirect pathway via the reticular thalamic nucleus (RT) from the substantia nigra pars reticulata (SNr) to the parafascicular thalamic nucleus (PF) by using anterograde and retrograde tract tracing methods. After biotinylated dextranamine (BDA) injection into the dorsolateral part of the SNr, many labeled fibers and axon terminals were distributed in the ventral part of the RT, as well as in the ventrolateral part of the PF, bilaterally with an ipsilateral dominance. After BDA injection into the ventral part of the RT, a plexus of labeled axons was found bilaterally with an ipsilateral dominance in the ventrolateral part of the PF. After combined injections of BDA into the dorsolateral part of the SNr and cholera toxin B subunit (CTb) into the ventrolateral part of the PF on the same side, overlapping distribution of BDA-labeled fibers and CTb-labeled neurons was observed in the ventral part of the RT ipsilateral to the injection sites, where the BDA-labeled axon terminals made symmetrical synaptic contacts with soma and dendrites of the CTb-labeled neurons. 相似文献
107.
Takaiwa M Nakano M Koseki K Yoshida J Iwasaki M Kuma Y Kushida N Kamata T Yokota T Yamaguchi O 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》2000,91(7-8):595-598
75 year old female who was hospitalized for abdominal pain and fever up on 12th May 1998. She had been followed as a polycystic kidney patient since few years. The swelling of the right kidney and her general condition became gradually worse. On 18th May, the embolization to the right kidney using pure alcohol and gelatin sponge was performed. Within a month, CT scan showed the reduced volume of the right kidney and her blood examination data as well as her general condition became gradually well. And on 17th June, she left our hospital without any complication. 相似文献
108.
109.
110.
Atsushi Fukui Megumi Yokota Ayano Funamizu Rika Nakamua Rie Fukuhara Kenichi Yamada Hidetaka Kimura Asami Fukuyama Mai Kamoi Kanji Tanaka Hideki Mizunuma 《American journal of reproductive immunology (New York, N.Y. : 1989)》2012,67(4):278-286
The regulation of uterine and circulating peripheral blood natural killer (NK) cells has been associated with reproductive immunology such as recurrent pregnancy losses, implantation failures, or preeclampsia. Preeclampsia is a hypertensive disorder of pregnancy characterized by increased blood pressure accompanied by proteinuria and is a major cause of maternal and fetal mortality. Natural cytotoxicity receptors (NCRs) are unique markers, which regulate NK cell cytotoxicity and cytokine production. The relation of NCRs to reproduction is not fully characterized yet. The different profile of NCRs expression may suggest presence of abnormal regulation of NK cell in women with reproductive failures. Pregnant women with preeclampsia carry immunological abnormalities of NCRs on peripheral blood NK cells during pregnancy. The lower expression of NKp46+ NK cells in women with preeclampsia may account for the higher production of NK1 cytokine that is known as NK1 shift in pregnant women with preeclampsia. Evaluation of NKp46 on peripheral blood NK cells may be applicable to find the onset of preeclampsia. In this review, various expressions of NK cell surface markers including NCRs on NK cells, NK cell cytotoxicity, and production of cytokines and angiogenic factors by NK cells were reviewed in relation to preeclampsia. 相似文献