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G L Mutter

Publications and source records attributed to G L Mutter.

At least 55 records · Page 3Linked to original sources
PubMed1995

A polymerase chain reaction assay for non-random X chromosome inactivation identifies monoclonal endometrial cancers and precancers.

We hypothesize that endometrial carcinoma and their precursors share a monoclonal growth pattern and tested this thesis with archival paraffin-embedded tissues using a polymerase chain reaction-based assay for non-random X chromosome inactivation. Of the 10 well-differentiated endometrial adenocarcinoma cases with heterozygous markers (HUMARA, X-linked androgen receptor gene), 9 had skewed X inactivation consistent with a monoclonal process, and one contained a structurally altered HUMARA gene. X inactivation skewing similar to that of the tumor was seen in matched control polyclonal tissues of 4 (of 9) cases, caused by the small number of endometrial stem cells at the time of embryonic X inactivation. When the polymerase chain reaction assay was applied to four potential endometrial precancers (atypical endometrial hyperplasia) and matched control tissues, two were inconclusive, and two were found to be monoclonal. We conclude that 1) it is essential to include polyclonal control tissues in X inactivation analyses to determine whether skewing is a specific indicator of monoclonality; and 2) endometrial adenocarcinomas and some putative precancers, atypical endometrial hyperplasia, are monoclonal.

Adenocarcinoma↗
PubMed1994

Analysis of HPV-positive and -negative vulvar carcinomas for alterations in c-myc, Ha-, Ki-, and N-ras genes.

Mutation or overexpression of certain host genes, including c-myc, Ha-ras, and Ki-ras, have been associated with genital squamous neoplasia, specifically in the cervix, and have been implicated in the natural history of these tumors. The relationship of these host gene alterations to vulvar squamous cell carcinomas has not been previously studied. We analyzed archival material from 13 human papillomavirus-positive and -negative vulvar squamous cell carcinomas for mutations in Ha-, Ki-, and N-ras genes, and a smaller number of fresh samples for c-myc amplification, using PCR-based assays. For comparison, eight cervical squamous cell carcinomas (three fixed and five fresh) were also analyzed. Analysis for ras mutations revealed a previously reported silent allelic variant at nucleotide 1744 in the Ha-ras gene, but no mutations in codons 12, 13, or 61. Similarly, genomic amplification of c-myc beyond a maximum of three haploid copies was not identified in the cases. These findings indicate that alterations in myc or ras sequences are not linked to vulvar squamous cell carcinomas or to the presence or absence of HPV nucleic acids. Moreover, they apparently will not distinguish vulvar from cervical carcinomas, both groups appearing to be unlikely to harbor these sequence alterations.

Base Sequence↗
PubMed1994

Multinucleated atypia of the vulva. Report of a distinct entity not associated with human papillomavirus.

The vulvar mucosa often demonstrates epithelial nuclear atypia in association with reactive and inflammatory conditions. These nuclear changes are usually mild and can be readily distinguished from vulvar intraepithelial neoplasia (VIN) and human papillomavirus (HPV)-related lesions. In a recent survey of vulvar biopsies in reproductive-aged women, we identified 12 cases of an unusual pattern of atypia associated with multinucleated epithelial cells but lacking the usual stigmata of reactive changes, condyloma, or VIN. The average age of the patients with multinucleated atypia of the vulva (MAV) was 37 years. The multinucleated cells were commonly in the lower to middle epithelial layers and contained between two and 10 nuclei, often with prominent nucleoli. In contrast to condyloma and VIN, there was no surface atypia, and the multinucleated cells lacked hyperchromasia, irregularity, or variation in nuclear size. No significant inflammation or identifiable infectious process was present, and none of the patients had received any topical treatment other than mild corticosteroids. Two of the patients had a history of VIN at a noncontiguous site. None of the 12 cases contained HPV DNA by either in situ hybridization or polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) analysis. This is in contrast to 49 of 65 women with VIN and 21 of 26 with condyloma who had HPV demonstrable by the PCR method (p < 0.00001). Immunoperoxidase stains for herpes types I and II were also negative in all the cases. Thus, MAV appears to be a distinct entity occurring in relatively young women; when it is not associated with condyloma or VIN, MAV is not related to HPV. As the morphologic features may overlap with both condyloma and VIN, it is important that MAV not be confused with these lesions or vice versa. It is not known whether MAV is a risk factor for VIN, represents an exaggerated reactive response, or is an entity with a distinct origin.

Adult↗
PubMed1994

Evaluation of gene deletions by quantitative polymerase chain reaction. Experience with the alpha-thalassemia model.

In order to evaluate the feasibility of using quantitative polymerase chain reaction (PCR) to evaluate gene dosage, we developed an assay to detect alpha-globin genes, which are frequently deleted in alpha-thalassemia patients. In this quantitative assay alpha-1 and alpha-2 globin consensus regions are coamplified by one oligonucleotide pair, along with a second primer pair targeting a single-copy reference gene, namely, tumor necrosis factor alpha, or TNF-alpha. A series of DNA samples titrating alpha-globin against TNF-alpha DNA have a strong linear relationship between template ratios and product ratios (r > 0.98). Minimal sequence divergence (91% homology) between alpha-1 and alpha-2, internal to the identical primer annealing sites, results in a lower amplification efficiency for alpha-1, to 94% of alpha-2 for each cycle. Furthermore, when applied to a variety of individual DNA samples, the signal ratios of alpha-globin to TNF-alpha were far more variable than previously observed for titrated control DNA. We conclude that DNA isolates from different individuals may have idiosyncratic changes in amplification efficiency owing to polymorphic sequence variation and/or variable presence of unidentified contaminants. Despite these potentially confounding factors, however, we were able to identify by quantitative PCR a single gene deletion later confirmed by Southern blot analysis in 20 individual DNA samples.

Base Sequence↗
PubMed1994

Restriction fragment length polymorphism analysis of isotype-labeled polymerase chain reaction-amplified human papillomavirus DNA combines sensitivity with built-in contaminant detection.

The detection of low copy number DNA in archival tissue has been revolutionized by polymerase chain reaction (PCR), but widespread acceptance of this technique for diagnostic purposes has been hampered by problems with contamination. There is a technique, restriction fragment length polymorphism analysis for characterizing PCR-amplified human Papillomavirus (HPV) nucleic acids, that reportedly provides for increased sensitivity in detection of both target and contaminating sequences. This technique is a modification of standard restriction fragment length polymorphism and involves radiolabeled nucleotide incorporation during PCR and restriction enzyme digestion of the products followed by high resolution polyacrylamide gel electrophoresis. The amount of initial target DNA amplified by PCR that can be detected by isotope labeling or ethidium staining was compared, as was the sensitivity of the two methods for analyzing a PCR product of fixed amount. The sensitivity of ethidium staining or autoradiography was comparable for detection of initial target HPV DNA by PCR. However, for subsequent typing of amplified HPV DNA by restriction fragment length polymorphism, isotope-labeled products provided an approximately 125-fold increase in sensitivity over ethidium staining, with a maximum of 625-fold greater sensitivity with a 3-day exposure. The detection of low levels of potential contaminants in PCR-amplified HPV DNA was determined in a serial analysis of cervical biopsies. Contaminating DNA was identified in two gels where multiple samples yielded the same restriction pattern. On re-isolation of genomic DNA, these products of contaminating DNA were not seen. Extrapolating from the above experiments, the contamination of many samples would have escaped detection by ethidium staining alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1994

Advances in the molecular biology of gestational trophoblastic disease.

Gestational trophoblastic diseases are a heterogeneous pool of clinically and histopathologically defined entities with two clinically relevant features: reproductive failure and a high neoplastic potential. Here we review recent advances in understanding the biology and natural history of the most common form of trophoblastic disease, hydatidiform mole, with an emphasis on the clinical implications for patient management. There are no reliable genetic markers for predicting which subset of moles will behave aggressively, nor are there molecular diagnostic methods at present that offer advances over traditional histopathology. The predominant genetic finding in complete and partial hydatidiform moles is an imbalance of parental chromosomes, completely androgenetic (paternal) in the former and an extra paternal haploid set in the latter. This lack or imbalance of a maternal genomic contribution probably changes the gene expression since there is no evidence of gene mutation in these lesions.

Animals↗
PubMed1993

Differential expression of the proto-oncogenes c-abl and c-mos in developing mouse germ cells.

C-abl and c-mos, two proto-oncogenes with unique patterns of expression in gonadal tissues, were examined by in situ hybridization with respect to their expression in the germ line. C-abl transcripts were observed to be most abundant in late round spermatids and elongating spermatids. C-mos transcripts were also expressed in round spermatids, but at much reduced levels compared to the levels of c-abl. C-abl mRNAs were also detected in mouse oocytes which have entered the growth phase. This temporal specificity of accumulation of c-abl transcripts was similar to that observed for c-mos, which also accumulates in growing and fully grown oocytes (follicle stages 4-6). Quantitative evaluation suggested that c-abl mRNA levels in oocytes are at least an order of magnitude lower than those of c-mos transcripts.

Aging↗
PubMed1993

Sex chromosome composition of complete hydatidiform moles: relationship to metastasis.

OBJECTIVE: Complete hydatidiform moles have a substantial risk for subsequent development of persistent or metastatic gestational trophoblastic tumor. We evaluated the hypothesis that presence of a Y chromosome in a complete hydatidiform mole confers an increased risk for developing metastatic gestational trophoblastic tumor. STUDY DESIGN: The polymerase chain reaction was applied to archival paraffin-embedded molar-tissue to identify Y chromosome-positive dispermic moles in patients who did or did not develop metastatic disease. To reduce the chances of analytic error, consensus polymerase chain reaction primers directed at homologous but different genes present on both X and Y chromosomes were used. RESULTS: Y-chromosome sequences were identified in 7.7% (1/13) of the metastatic group and 9.1% (2/22) of the nonmetastatic group, a statistically insignificant difference. CONCLUSION: We are unable to confirm any increased risk for metastasis in Y chromosome-positive compared with Y chromosome-negative complete hydatidiform mole.

Base Sequence↗
PubMed1993

The sex ratio of normal and manipulated human sperm quantitated by the polymerase chain reaction.

OBJECTIVE: To establish the primary sex ratio, the relative abundance of X and Y chromosome-bearing sperm, in unselected sperm and in sperm selected by swim-up or Sephadex filtration (SpermPrep column; Fertility Technologies, Inc., Natick, MA). This was done to evaluate the possibility that these semen manipulations change the primary sex ratio. DESIGN: Ninety-eight unmanipulated semen samples were analyzed for sex chromosome content using quantitative polymerase chain reaction (PCR). A smaller number of samples was analyzed before and after either swim-up or Sephadex filtration. RESULTS: The mean percentage of all sex chromosomes identified as a Y chromosome in unmanipulated semen samples ranged from 41.9% to 56.7%, with a mean average of 50.3%. There was no significant change in sex chromosome composition after either swim-up (n = 17) or column filtration (n = 20). CONCLUSIONS: The chromosome compositions of semen samples from a large number of men have equal numbers of X and Y. Swim-up and SpermPrep filtration do not appear to alter the primary sex ratio.

Humans↗
PubMed1993

Oppositely imprinted genes H19 and insulin-like growth factor 2 are coexpressed in human androgenetic trophoblast.

Human uniparental gestations such as gynogenetic ovarian teratomas and androgenetic complete hydatidiform moles provide a model to evaluate the integrity of parent-specific gene expression--i.e., imprinting--in the absence of a complementary parental genetic contribution. We studied expression, in these tissues, of the oppositely imprinted genes H19, which is an embryonic nontranslated RNA, and insulin-like growth factor type 2 (IGF2). Normal gestations only express H19 from the maternal allele and express IGF2 from the paternal allele, whereas neither is expressed from the maternal genome of gynogenetic gestations, and both are expressed from the paternal genome of androgenetic gestations. Coexpression of H19 and IGF2 in the androgenetic tissues was in a single population of cells, mononuclear trophoblast--the same cell type expressing these genes in biparental placentas. These results demonstrate that a biparental genome may be required for expression of the reciprocal IGF2/H19 imprint. Alternatively, biparental expression may be a normal feature of some imprinted genes in specific cell types. Additional experiments with other imprinted genes will clarify whether this reflects global failure of the imprinting process or a change specific to the IGF2/H19 locus.

Base Sequence↗
PubMed1992

The effect of consecutive day inseminations on semen characteristics in an intrauterine insemination program.

This study demonstrates a statistically significant decrease in semen volume, sperm concentration, and sperm motility in samples obtained on the 2nd day of consecutive day inseminations in an IUI program. This diminution in semen characteristics persists despite sperm washing. The effects of a second ejaculation on semen parameters in oligospermic and asthenospermic men were mixed. Thus, in general, sperm-washing procedures cannot overcome the natural reduction in semen quality produced by frequent ejaculations. Clinicians may wish to use this information in timing IUI cycle inseminations.

Ejaculation↗
PubMed1991

Molecular diagnosis of sex chromosome aneuploidy using quantitative PCR.

Numeric sex chromosome imbalances, or aneuploidies, are present in several pathological conditions including tumors, abnormal gestations, and clinical syndromes. Here we report a method to identify karyotypic imbalances of the X and Y chromosomes using the polymerase chain reaction (PCR). The polymerase chain reaction was used to quantitatively coamplify the sex chromosome linked genes ZFX and ZFY. Quantitation was facilitated by 1) use of a single primer set which recognizes both templates, 2) incorporation of radiolabelled nucleotides during amplification, and 3) use of amplification conditions which minimize heteroduplex formation. High accuracy of the method was confirmed by concordance with values expected from titrated male and female DNAs and cells from patients with sex chromosome aneuploidy. This approach provides a rapid and reproducible method of evaluating relative abundance of allelic genes, and might be applied to detection of autosomal aneuploidy.

Aneuploidy↗
PubMed1991

Testis-specific expression of the human MYCL2 gene.

We have characterized the expression of MYCL2, an intronless X-linked gene related to MYCL1. RNase protection analysis of a panel of human normal and tumor tissues has revealed that MYCL2 is expressed almost exclusively in human adult normal testis; much lower levels of transcript were detected in one human lung adenocarcinoma. No MYCL2 transcript was found in human testis RNA obtained from second trimester fetuses. This observation suggests a germ cell rather than somatic cell origin of the transcript and possible developmental regulation of MYCL2. Northern blot analysis of poly(A)+ RNA from adult human normal testis with an antisense riboprobe revealed a transcript of approximately 4.8-kb, which is in agreement with the size predicted from the MYCL2 nucleotide sequence. Antisense transcripts were found spanning regions of MYCL2 corresponding to all three exons of MYCL1. No sizable open reading frame was seen for the MYCL2 antisense transcripts suggesting that they may represent either regulatory sequences or an intron of a gene encoded by the complementary strand. RNase protection assays and the 5' RACE protocol (Rapid Amplification of cDNA Ends) were used to address the localization of the transcription start site of the MYCL2 sense transcript and different putative promoters and transcription regulatory elements have been identified.

Amino Acid Sequence↗
PubMed1988

Evidence for the involvement of the proto-oncogene c-mos in mammalian meiotic maturation and possibly very early embryogenesis.

The c-mos proto-oncogene exists as a maternal mRNA in mammalian oocytes, in that it has been shown to accumulate in mouse oocytes during the growth phase and to be present at high levels in fully grown oocytes. The function of c-mos during the subsequent development of the oocytes and embryos was examined by determining the fate of the oocyte c-mos mRNAs by in situ hybridization and Northern blot hybridization analysis. A substantial decrease in the levels of c-mos transcripts was observed in oocytes undergoing meiotic maturation. By the two-cell stage, levels of c-mos transcripts dropped to below the limits of detection using in situ hybridization. c-mos transcripts remained undectable through the blastocyst stage of embryogenesis. Analysis of meiotic maturation in vitro permitted finer temporal resolution of the initial drop in c-mos levels. Between approximately 7 and 17 h of culture, the amount of c-mos mRNA fell to 18-43% of the levels found in the fully grown oocyte. This interval corresponds to the progression of meiotic maturation from metaphase I to metaphase II. Our in vivo studies showed that ovulation per se is not the stimulus for the drop in c-mos transcript levels, since preovulatory metaphase II oocytes exhibited this decline to a degree comparable to that of ovulated metaphase II oocytes. The development specificity of c-mos transcript levels suggests a role of this putative serine kinase in the meiotic maturation of mammalian germ cells.

Bucladesine↗
PubMed1987

Bleomycin-associated pulmonary fibrosis: rapidly fatal progression without chest radiotherapy.

Two patients with carcinoma of the tonsil were treated with bleomycin (396 and 224 units, respectively) but not with radiotherapy. Respiratory insufficiency led to death 45 and 52 days, respectively, after onset of therapy. Chest radiographs before bleomycin therapy revealed no evidence for lung disease. Postmortem examinations showed severe interstitial and intraalveolar pulmonary fibrosis. Comparably rapid progression from radiographically normal pulmonary parenchyma to fatal fibrosis has been documented previously only in patients with thoracic neoplasia as well as, in all but one instance, either prior or concurrent chest radiotherapy. These two cases indicate that chest radiotherapy is not a necessary cofactor for the development of rapidly progressive, fatal, diffuse interstitial pulmonary fibrosis after bleomycin therapy.

Aged↗
PubMed1987

Distinct developmental patterns of c-mos protooncogene expression in female and male mouse germ cells.

The protooncogene c-mos is expressed in murine reproductive tissues, producing transcripts of 1.7 and 1.4 kilobases in testis and ovary, respectively. In situ hybridization analysis of c-mos expression in histological sections of mouse ovaries revealed that oocytes are the predominant if not exclusive source of c-mos transcripts. c-mos transcripts accumulate in growing oocytes, increasing 40- to 90-fold during oocyte and follicular development. c-mos transcripts were also detected in male germ cells and are most abundant after the cells have entered the haploid stage of spermatogenesis. This developmentally regulated pattern of c-mos expression in oocytes and spermatogenic cells suggests that the c-mos gene product may have a function in normal germ-cell differentiation or early embryogenesis.

Animals↗
PubMed1987

Differential expression in murine somatic and germinal tissues of transcripts homologous to an abundant embryonal-carcinoma-cell mRNA.

EC1, a clone from a cDNA library of embryonal-carcinoma (EC) cells, was used to study the expression of the gene(s) homologous to this sequence in murine germ cells and somatic tissues. Northern-blot analysis was used to determine the size and relative abundance of ECl transcripts in EC cells, ovary, testis, liver, spleen, brain, thymus, and bone marrow. The stage-specific expression of EC1-related transcripts in meiotic cells was examined in enriched populations of testicular cells (meiotic prophase spermatocytes, early and late spermatids, and residual bodies). All tissues and cells examined contained mRNAs of approximately 1.3 and approximately 3.6 kb which were homologous to EC1. In RNA from liver and thymus, a faint, lower-molecular-weight transcript of 0.75 kb was seen. A unique pattern of expression was observed in male germ cells. In cells that had completed meiosis, two additional transcripts of 1.0 and 4.4 kb were visualized, as well as high levels of expression of the 1.3- and 3.6-kb species. Only the 1.3- and 3.6-kb transcripts were detected in ovarian RNAs. The high level and stage specificity of expression of EC1-related mRNAs in germ cells suggest that this gene may be important in meiosis or in germ-cell maturation.

Animals↗