To see whether mutant-K-RAS polyclonality is a common and specific feature of pancreatic carcinogenesis, we investigated a unselected series of periampullary cancers (41 pancreatic, 13 biliary and two ampullary adenocarcinomas).
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).
These differences were statistically significant within the subset of adenocarcinomas harboring activating KRAS mutations, suggesting a synergistic relationship between amplification and mutation.
Adenocarcinoma with KRAS mutation showed a higher value of Ki-67/MIB1 (65% vs 35%, p=0.048) and prevalent solid pattern (35% vs 10%, p=0.019) in comparison to wild-type form.
MLL2 and KRAS mutations were only seen in adenocarcinoma ex goblet cell carcinoids and TP53 mutations were limited to poorly differentiated adenocarcinoma ex goblet cell carcinoids (2/34).
Additionally, we evaluate the classical mutations of EGFR, KRAS in the 9 cases of PEACs, it turned out that all tumors were EGFR-wild and KRAS-wild types, which confirmed that PEAC has a separate phenotype from usual pulmonary adenocarcinoma.
Our results highlight the differential expression of K-RAS4A and K-RAS4B in advanced adenocarcinoma NSCLC patients and underline the need to further clarify the enigma behind their biological significance in various cancer types, including NSCLC.
We sought to determine whether transcriptional subgroups of clinical relevance exist within EGFR-mutated, KRAS-mutated, or EGFR and KRAS wild-type (EGFRwt/KRASwt) adenocarcinomas.
To determine if the incidence of H- and K-ras gene mutations in these rat tumors is similar to that in human endometrial cancers, we isolated DNA samples from 2 atypical hyperplasias, 5 simple or complex hyperplasia without atypia, 9 adenocarcinomas and 7 histologically normal tissues, amplified exons 1 and 2 of the H- and K-ras genes by PCR and hybridized the products with allele specific oligonucleotide probes.
In addition, point mutations of the c-Ki-ras gene were detected in 1 gastric-type adenocarcinoma and 2 intestinal-type adenocarcinomas, suggesting the occurrence of a common genetic abnormality.
Since little is known of its role in pancreatic cancers, we investigated changes in telomerase activity in human pancreatic duct adenocarcinomas and compared the frequency of increased telomerase activity with the presence of K-ras gene mutations.
Between the AIS of smokers and nonsmokers, only the sex ratio was significantly different; all the other clinicopathologic factors including TTF-1 and driver mutations were not significantly different: EGFR and KRAS mutation rates (smokers:nonsmokers) were 61:58 (%) (P=0.7) and 6.1:1.4 (%) (P=0.2), respectively, whereas, in invasive adenocarcinomas, the rates were 41:69 (%) (P<0.001) and 9.4:2.3 (%) (P<0.04), respectively.
For KRAS, mutations occurred in adenocarcinoma only (21 of 215) and were associated with smokers (11 of 58; P = 0.003), men (14 of 84; P = 0.009) and poorly differentiated (7 of 41) compared with well-differentiated (4 of 86) tumors (P = 0.037).
Combination of IPA-3 or OTSSP167 and auranofin was highly synergistic in EGFR or KRAS mutant adenocarcinoma and squamous cell carcinoma cell lines and decreased tumor volume in mice models.
The two essential requirements for pathologic specimens in the era of personalized therapies for non-small cell lung carcinoma (NSCLC) are accurate subtyping as adenocarcinoma (ADC) versus squamous cell carcinoma (SqCC) and suitability for EGFR molecular testing, as well as for testing of other oncogenes such as EML4-ALK and KRAS.