0000000000314001
AUTHOR
Carla Tubiolo
Specific codon 13 K-ras mutations are predictive of clinical outcome in colorectal cancer patients, whereas codon 12 K-ras mutations are associated with mucinous histotype
Background: K-ras mutations, one of the earliest events observed in colorectal carcinogenesis, are mostly found in codons 12 and 13, and less frequently in codon 61, all three of which are estimated to be critical for the biological activity of the protein. Nevertheless the prognostic significance of such mutations remains controversial. Our purpose was to assess whether any or specific K-ras mutations in primary colorectal cancer had prognostic significance and were linked to clinico-pathological parameters. Patients and methods: Paired tumor and normal tissue samples from a consecutive series of 160 untreated patients (median of follow up 71 months), undergoing resective surgery for prima…
DNA ploidy and S-phase fraction, but not p53 or NM23-H1 expression, predict outcome in colorectal cancer patients. Result of a 5-year prospective study.
Purpose: The aim of this study was to determine TP53 and NM23-H1 immunoreactivity, DNA ploidy, and S-phase fraction (SPF) in a series of 160 patients undergoing resective surgery for primary operable colorectal cancer (CRC) and to establish whether these alterations have any clinical value in predicting CRC patients' prognosis. Methods: TP53 and NM23-H1 expressions were evaluated on paraffin-embedded tissue by immunohistochemistry and DNA-ploidy and SPF on frozen tissue by flow-cytometric analysis. Results: The median follow-up time in our study group was 71 months (range 34-115 months). P53 protein expression was associated with distal tumors (P < 0.05) and DNA aneuploid tumors (P < …
DNA aneuploidy and high proliferative activity but not K-ras-2 mutations as independent predictors of clinical outcome in operable gastric carcinoma: Results of a 5-year Gruppo Oncologico dell'Italia Meridionale (GOIM) prospective study
BACKGROUND The prognostic value of DNA ploidy, S-phase fraction (SPF) and K-ras-2 mutations in gastric carcinoma (GC) has not yet been clearly defined. The aim of this study was to clarify the association between biomolecular variables, tumor characteristics, and clinical outcome in GC patients. METHODS Resected specimens from a consecutive series of 69 patients with GC who underwent potentially curative surgery were studied prospectively. DNA ploidy and SPF were assessed by flow cytometry on multiple frozen tumor samples, whereas K-ras-2 mutations were detected by polymerase chain reaction followed by single-strand conformation polymorphism. All the patients involved in this study were fol…
Havep53gene mutations and protein expression a different biological significance in colorectal cancer?*
p53 alterations are considered the most common genetic events in many types of neoplasms, including colorectal carcinoma (CRC). These alterations include mutations of the gene and/or overexpression of the protein. The aim of our study was to assess whether in 160 patients undergoing resective surgery for primary operable CRC there was an association between p53 mutations and protein overexpression and between these and other biological variables, such as cell DNA content (DNA-ploidy) and S-phase fraction (SPF), and the traditional clinicopathological variables. p53 mutations, identified by PCR-SSCP-sequencing analysis, were found in 68/160 patients (43%) and positive staining for p53 protei…