{"id":1147,"date":"2019-06-04T14:49:24","date_gmt":"2019-06-04T06:49:24","guid":{"rendered":"http:\/\/www.bioactivescreeninglibrary.com\/?p=1147"},"modified":"2022-01-07T10:53:34","modified_gmt":"2022-01-07T02:53:34","slug":"potent-effects-dominant-oncogenes-preclude","status":"publish","type":"post","link":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/2019\/06\/04\/potent-effects-dominant-oncogenes-preclude\/","title":{"rendered":"We found a mean value while the potent effects of dominant oncogenes preclude"},"content":{"rendered":"

MASI led us to question the commonly held belief that tumorigenesis requires biallelic inactivation for tumor suppressor genes the necessity of loss of the wild type Dexrazoxane hydrochloride<\/a> allele product. We examined a public database of mutations. We found, as expected, that most inactivating mutations of tumor suppressor genes were frequently accompanied by loss of the wild type allele. However, our earlier observations on homozygosity of oncogenes were confirmed by the finding that 20% of five activating oncogene mutations were homozygous in cell lines derived from multiple tumor types. As discussed below, the true incidence of MASI is considerably higher as quatitative copy number data are missing in the Sanger database. Thus MASI, while a long observed and expected phenomenon for tumor suppressor genes, is also present in an important subset of cells harboring mutant oncogenes. Other published evidence supports this concept. Detection of MASI of an oncogene requires three basic determinations: 1) detection of an Chloroquine Phosphate<\/a> oncogenic mutation; 2) copy number enumeration of the mutant gene in the tumor cells and 3) determination of the relative ratio of the mutant: wild type allele. Standard and widely accepted methods for the first two determinations exist including direct sequencing for mutations, and qPCR, FISH, aCGH or SNP analyses for CNGs. For cell lines mA% can be determined by subcloning or by the presence of homozygosisty of the mutant allele. In order to avoid laborious and time intensive subcloning, we determined that mA% could be accurately estimated by measurements of the relative peak heights present on the electropherograms of routine sequencing for mutation detection. While mA% could be determined accurately in cell lines by these simple techniques, tumor samples present a much greater problem because of contamination with highly variable percentages of non-malignant cells. Reports of molecular studies often provide estimates of the percentage of tumor cells by histologic examination, but these are usually performed rapidly and are relatively inaccurate. In addition, because of the frequent presence of tumor cell polyploidy, most genetic analyses require determination of the percentage of tumor DNA in the examined sample, rather than the percentage of tumor cells. For our studies, we used SNP array data for determinations of tumor cell DNA percentages. While this approach has been used by others, we refined the methodology.<\/p>\n","protected":false},"excerpt":{"rendered":"

MASI led us to question the commonly held belief that tumorigenesis requires biallelic inactivation for tumor suppressor genes the necessity of loss of the wild type Dexrazoxane hydrochloride allele product. We examined a public database of mutations. We found, as expected, that most inactivating mutations of tumor suppressor genes were frequently accompanied by loss of … Continue reading “We found a mean value while the potent effects of dominant oncogenes preclude”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/1147"}],"collection":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/comments?post=1147"}],"version-history":[{"count":1,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/1147\/revisions"}],"predecessor-version":[{"id":1148,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/posts\/1147\/revisions\/1148"}],"wp:attachment":[{"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/media?parent=1147"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/categories?post=1147"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.bioactivescreeninglibrary.com\/index.php\/wp-json\/wp\/v2\/tags?post=1147"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}