GNAS mutations (p.R201H, c.602G>A and p.R201C, and c.602C>T) were identified in 17 (31%) of 55 of disseminated mucinous neoplasms and were found in 8 (35%) of 23 low-grade mucinous neoplasms, 7 (37%) of 19 high-grade mucinous adenocarcinomas lacking a signet ring cell component, and 2 (15%) of 13 high-grade mucinous adenocarcinomas with a signet ring cell component.
Activating GNAS mutations were found in 8 of the 19 lobular endocervical glandular hyperplasias (LEGH; 42%) and 4 of the 79 endocervical-type mucinous adenocarcinomas (5%) but were never seen in the normal endocervical tissue, minimal deviation adenocarcinomas, endometrioid adenocarcinomas, or squamous cell carcinomas.
This patient had been operated on for an unusually large invasive colloid adenocarcinoma (pT3N0M0 R0) derived from an intestinal subtype GNAS-mutated IPMN.
KRAS mutations with synchronous TP53 mutations occur predominantly in low-grade mucinous carcinomas, suggesting a specific molecular background of this ovarian cancer type.
A mutational analysis identified activating GNAS mutations in 16 of 32 low-grade appendiceal mucinous neoplasms (LAMNs) but in none of three mucinous adenocarcinomas (MACs).
KRAS mutations with synchronous TP53 mutations occur predominantly in low-grade mucinous carcinomas, suggesting a specific molecular background of this ovarian cancer type.
We compared the degree of immunostaining for matrix metalloproteinase-7 (MMP-7), laminin-5, and geminin in the mucinous adenocarcinoma with and without KRAS mutation.
The cytokeratin, mucin core protein, CDX2, Ki-67 and p53 expression patterns are identical in the xenograft and resected tumour and are consistent with the expected pattern of protein expression for mucinous adenocarcinoma of the appendix.
This study aimed to evaluate the status of BRAF together with K-ras, p53 and mismatch-repair deficiency to clarify their association with tumorigenesis of colorectal MC.
Missense mutations in KRAS codon 12 were detected in six of seven (86%) mucinous adenocarcinomas but only 3 of 18 (17%) nonmucinous adenocarcinomas (P = 0.003).
Clinicopathological characteristics, microsatellite instability, and expression of mucin core proteins and p53 in colorectal mucinous adenocarcinomas in relation to location.
This is the first report that characterized the immunophenotypic profile of appendiceal epithelial neoplasms with an emphasis of a higher frequency of p53 positivity in mucinous carcinoma cases compared with mucinous adenoma in the appendix.
MSS tumors of MC also showed a higher frequency of p53 and DCC inactivation (p53, 45% by IHC, p=0.02 and 53% by LOH, p=0.005; DCC, 82%, p=0.001) compared to MSI tumors of MC (p53, 0% by IHC and 0% for LOH; DCC, 17%).
Expression of mucin core proteins, trefoil factors, APC and p21 in subsets of colorectal polyps and cancers suggests a distinct pathway of pathogenesis of mucinous carcinoma of the colorectum.
To examine the relationship between subsets of colorectal polyps and non-mucinous and mucinous adenocarcinomas of the colorectum, we evaluated the frequency of the expression of cell lineage associated mucin core proteins (MUC5AC and MUC2), trefoil factors (TFF1 and TFF3), and APC and p21 in these tissues.