KRAS mutations upregulate Runx1 to promote occurrence of head and neck squamous cell carcinoma

Gene mutations play an important role in head and neck squamous cell carcinoma (HNSCC) by not only promoting the occurrence and progression of HNSCC but also affecting sensitivity to treatment and prognosis. KRAS is one of the most frequently mutated oncogenes, which has been reported to have a mutation rate from 1.7% to 12.7% and may lead to poor prognosis in HNSCC, but its role remains unclear. Here, we found that the KRAS mutation can promote HNSCC generation through synergism with 4-Nitroquinoline-1-Oxide(4NQO). Mechanistically, KRAS mutations can significantly upregulate Runx1 to promote oral epithelial cell proliferation and migration and inhibit apoptosis. Runx1 inhibitor Ro 5-3335 can effectively inhibit KRAS-mutated HNSCC progression both in vitro and in vivo. These findings suggest that the KRAS mutation plays an important role in HNSCC and that Runx1 may be a novel therapeutic target for KRAS-mutated HNSCC.     

KRAS mutation and immunohistochemical profile in intraductal papillary neoplasm of the intrahepatic bile ducts

Intraductal papillary neoplasm of bile duct (IPNB) is characterized by a spectrum of diseases ranging from low-grade intraepithelial neoplasia to invasive carcinoma. In the present study, we aimed to investigate immunophenotypic features and KRAS mutations in relation to pathological subtypes and grades in Chinese patients with IPNBs. A total of 46 patients with IPNBs and 11 invasive adenocarcinomas arising in IPNBs (invasive IPNBs) were enrolled and clinicopathological data were analyzed. It was found that CK7 was expressed in 42 of the 46 neoplastic lesions. HepPar1 was expressed in 11 of the 46 noninvasive IPNBs, but not in invasive IPNBs. Additionally, CK19 was frequently expressed in both noninvasive IPNBs and invasive IPNBs. The intestinal-type IPNBs had a significantly higher percentage of MUC2 expression relative to the pancreaticobiliary (P = 0.015) and gastric-type IPNBs (P < 0.001). High-grade IPNBs and invasive IPNBs showed increased expression of cyclin D1, Ki-67, p53, mCEA, and CA19-9. The rate of KRAS mutation was significantly higher in high-grade IPNBs (P = 0.001) and invasive IPNBs (P = 0.006) than that in low- to intermediate-grade IPNBs. Additionally, KRAS mutation was significantly associated with tumor size, and Ki-67 expression. In conclusion, the expression of cyclin D, Ki-67, p53, mCEA and CA19-9 and KRAS mutation status are significantly correlated with histological grades of IPNBs.     

Phenotypic and genotypic differences in colorectal carcinoma among Caucasians,Asians, and Hispanics lack statistical significance

Colorectal carcinoma (CRC) has been shown to have both genetic and environmental factors that can promote carcinoma development. Previous studies have found ethnic differences in the distribution of molecular phenotypes of CRC. Very little specific data exist regarding Hispanic CRC, and these data primarily focus on epidemiology or location of carcinoma. Our retrospective study analyzed 562 Caucasian, Asian, and Hispanic CRC patients at the UCI Medical Center from 2004 to 2012. The results showed that there were no statistically significant differences with respect to mean age, gender or site of carcinoma among the three ethnic groups. There were no statistically significant differences among the three ethnicities with respect to rates of MSI, mutated BRAF, and mutated KRAS. The Caucasian group had a non-significant higher rate of MSI (15%) and BRAF mutation (12%) than the Asian and Hispanic groups. Hispanics had a non-significant higher rate of KRAS mutation (59%) than Caucasians (38%) and Asians (37%). The results of this study demonstrated a higher rate of MSI and BRAF mutation in the Caucasian group and a higher rate of KRAS mutation in the Hispanic group, however differences were not statistically significant.     

Colorectal serrated pathway cancers and precursors

The serrated pathway (SP) can be viewed as two parallel, but partially overlapping, arrays of colorectal precursor lesions, and their respective endpoint carcinomas, that are distinct from those of the conventional adenoma–carcinoma sequence (APC‐pathway). In this review we focus at the outset on the clinical impact, pathological features, molecular genetics and biological behaviours of the various SP cancers. Then we summarize the clinicopathological features, classification and molecular profiles of the two main precursor lesions that anchor the respective pathways: (i) sessile serrated adenoma/polyp (SSA/P), also called sessile serrated lesion (SSL), and (ii) traditional serrated adenoma (TSA). Activating mutations of the RAS–RAF–MAPK pathway initiate and sustain the lesions of the SP, and CpG island methylation of the promoter regions of tumour suppressor and DNA repair genes play the major role in their neoplastic progression. The SP includes microsatellite stable (MSS) carcinomas that are among the most biologically aggressive colorectal carcinomas (CRC), and also accounts for the great preponderance of sporadic hypermutated, mismatch repair (MMR)‐deficient or microsatellite instable (MSI) CRC. The identification, removal and appropriate classification of at‐risk SP precursors and surveillance of individuals who harbour these lesions present a challenge and opportunity for CRC prevention and mortality reduction.     

COPD-related adenocarcinoma presents low aggressiveness morphological and molecular features compared to smoker tumours

ObjectivesAdenocarcinoma comprises a group of diseases with heterogeneous clinical and molecular characteristics.COPD and lung cancer are strictly related; to date it is unknown if COPD-associated cancers have different features from tumours arising in non-COPD patients.Our aim was to study COPD-associated adenocarcinoma phenotypes mainly focusing on morphological and molecular aspects, in comparison to smoke-related cancer without COPD.Materials and methodsFrom 2010 to 2013, 54 patients with adenocarcinoma (20 COPD and 34 smokers) were prospectively studied. Each patient underwent a complete clinical and instrumental assessment.Morphological studies included analysis of growth pattern, cell proliferation (Ki-67/MIB1 expression) and parameters of intra- and peri-tumoral remodelling (inflammation, fibrosis and necrosis). Genetic analysis of EGFR and KRAS mutations was also performed.ResultsThe two groups were comparable for the main demographic and biohumoral parameters except for increased blood basophil cell count in the COPD group.Compared to COPD, tumours of smokers presented an increased percentage of solid component (median: 20% vs 5%, p = 0.02), a reduced percentage of lepidic pattern (median: 0% vs 10%, p = 0.06) and higher Ki-67/MIB1 median value (55% vs 30%, p = 0.02).In multivariate analysis lepidic and solid histological pattern were significantly influenced by clinical group (p = 0.03 and 0.05, respectively).Concerning EGFR mutation, no differences were found between groups while KRAS mutation presented a trend of higher percentage in smokers compared to COPD (41% vs 20%, p = NS).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.ConclusionsCOPD-related adenocarcinoma presents molecular and morphological features of lower aggressiveness (increased lepidic component, reduced solid pattern, lower cell proliferation and less frequent KRAS mutation) compared to smokers. Different molecular mechanisms could be associated with the development of COPD associated cancer.     

Consistent mutation status within histologically heterogeneous lung cancer lesions

Mattsson J S M, Imgenberg‐Kreuz J, Edlund K, Botling J & Micke P
(2012) Histopathology  61, 744–748 Consistent mutation status within histologically heterogeneous lung cancer lesions Aims: Activating epidermal growth factor receptor (EGFR) and KRAS mutations characterize molecular subgroups of non‐small‐cell lung cancer (NSCLC) with a strong predictive value for response to EGFR inhibitor therapy. However, the temporal occurrence and clonal stability of these mutations during the course of cancer progression are debated. The aim of this study was to characterize the presence of EGFR and KRAS mutations in histologically different areas of primary NSCLC lesions. Methods and results: Formalin‐fixed paraffin‐embedded cancer specimens from six cases with EGFR mutations and five cases with KRAS mutations were selected from a pool of primary resected NSCLC patients. From each tumour, three morphologically distinct areas were manually microdissected and analysed for the presence of mutations. The results demonstrated consistent EGFR and KRAS mutation status in the different histological areas of all primary tumours. Conclusions: The results support the concept that activating EGFR and KRAS mutations are oncogenic events that are consistently present throughout the primary tumour independently of histological heterogeneity. Thus, for molecular diagnostics, any part of the tumour is likely to be representative for EGFR and KRAS mutation testing.     

Ovarian mucinous tumor with mural nodules of anaplastic carcinoma: Three case reports

BACKGROUNDAnaplastic carcinoma mural nodules in ovarian mucinous tumors are very rare. This study aimed to report the morphological characteristics, molecular detection results, clinical treatment and prognosis of three ovarian mucinous tumors with mural nodules of anaplastic carcinoma.CASE SUMMARYThe pathomorphological features, molecular detection results, clinical treatment and prognosis of anaplastic carcinoma mural nodules were described in three cases. In case 1, sarcoma-like mural nodules (SLMNs) coexisted with anaplastic carcinoma mural nodules. No mutation was found in mucinous tumors. KRAS mutation was found in anaplastic carcinoma nodules and heterotypic cells were found in SLMNs. In case 2, KRAS mutation occurred in the mucinous epithelium and BRAF mutation occurred in mural nodules. In case 3, both mural nodules and mucinous tumors had the same KRAS mutation and a morphological transition between them was observed. All three patients died within 2 years, whether receiving chemotherapy or not. CONCLUSIONAnaplastic carcinoma mural nodules may develop from dedifferentiation of mucinous tumors or are unrelated to mucinous tumors.