Metastasising ameloblastoma or ameloblastic carcinoma? A case report with mutation analyses.

BACKGROUND: Ameloblastic carcinoma and metastasising ameloblastoma are rare epithelial odontogenic tumours with aggressive features. Distinguishing between these two lesions is often clinically difficult but necessary to predict tumour behaviour or to plan future therapy. Here, we provide a brief review of the literature available on these two types of lesions and present a new case report of a young man with an ameloblastoma displaying metastatic features. We also use this case to illustrate the similarities and differences between these two types of tumours and the difficulties of their differential diagnosis. CASE PRESENTATION: Our histopathological analyses uncovered a metastasising tumour with features of ameloblastic carcinoma, which developed from the ameloblastoma. We profiled the gene expression of Wnt pathway members in ameloblastoma sample of this patient, because multiple molecules of this pathway are involved in the establishing of cell polarity, cell migration or for epithelial-mesenchymal transition during tumour metastasis to evaluate features of tumor behaviour. Indeed, we found upregulation of several cell migration-related genes in our patient. Moreover, we uncovered somatic mutation BRAF p.V600E with known pathological role in cancerogenesis and germline heterozygous FANCA p.S858R mutation, whose interpretation in this context has not been discussed yet. CONCLUSIONS: In conclusion, we have uncovered a unique case of ameloblastic carcinoma associated with an alteration of Wnt signalling and the presence of BRAF mutation. Development of harmful state of our patient might be also supported by the germline mutation in one FANCA allele, however this has to be confirmed by further analyses.

RAD51 as a potential surrogate marker for DNA repair capacity in solid malignancies.

Targeting deficient mechanisms of cellular DNA repair still represents the basis for the treatment of the majority of solid tumors, and increased DNA repair capacity is a hallmark mechanism of resistance not only to DNA-damaging treatments such as cytotoxic drugs and radiotherapy, but also to small molecule targeted drugs such as inhibitors of poly-ADP ribose polymerase (PARP). Hence, there is substantial medical need for potent and convenient biomarkers of individual response to DNA-targeted treatment in personalized cancer care. RAD51 is a highly conserved protein that catalyzes DNA repair via homologous recombination, a major DNA repair pathway which directly modulates cellular sensitivity to DNA-damaging treatments. The clinical and biological significance of RAD51 protein expression is still under investigation. Pre-clinical studies consistently show the important role of nuclear RAD51 immunoreactivity in chemo- and radioresistance. Validating data from clinical trials however is limited at present, and some clinical studies show controversial results. This review gives a comprehensive overview on the current knowledge about the prognostic and predictive value of RAD51 protein expression and genetic variability in patients with solid malignancies.

Primitive neuroectodermal tumor (PNET) of the lung in an adult woman.

Primary primitive neuroectodermal tumors (PNETs) are extremely rare in the lung and especially in adult women. We describe a case of PNET of the lung with aggressive behavior in 31-year-old woman. Diagnosis was based on histopathological and immunohistochemical studies, and confirmed by molecular genetic analysis of chromosome rearrangements in the EWSR1 gene region. Clinical follow-up, post-mortem findings, and differential diagnosis are also discussed.

High expression of the RNA-binding protein RBPMS2 in gastrointestinal stromal tumors.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract and are often associated with KIT or PDGFRA gene mutations. GIST cells might arise from the interstitial cells of Cajal (ICCs) or from a mesenchymal precursor that is common to ICCs and smooth muscle cells (SMCs). Here, we analyzed the mRNA and protein expression of RNA-Binding Protein with Multiple Splicing-2 (RBPMS2), an early marker of gastrointestinal SMC precursors, in human GISTs (n=23) by in situ hybridization, quantitative RT-PCR analysis and immunohistochemistry. The mean RBPMS2 mRNA level in GISTs was 42-fold higher than in control gastrointestinal samples (p<0.001). RBPMS2 expression was not correlated with KIT and PDGFRA expression levels, but was higher in GISTs harboring KIT mutations than in tumors with wild type KIT and PDGFRA or in GISTs with PDGFRA mutations that were characterized by the lowest RBPMS2 levels. Moreover, RBPMS2 levels were 64-fold higher in GIST samples with high risk of aggressive behavior than in adult control gastrointestinal samples and 6.2-fold higher in high risk than in low risk GIST specimens. RBPMS2 protein level was high in 87% of the studied GISTs independently of their histological classification. Finally, by inhibiting the KIT signaling pathway in GIST882 cells, we show that RBPMS2 expression is independent of KIT activation. In conclusion, RBPMS2 is up-regulated in GISTs compared to normal adult gastrointestinal tissues, indicating that RBPMS2 might represent a new diagnostic marker for GISTs and a potential target for cancer therapy.

Clinical and prognostic significance of detecting CEA, EGFR, LunX, c-met and EpCAM mRNA-positive cells in the peripheral blood, tumor-draining blood and bone marrow of non-small cell lung cancer patients.

Background: Surgical treatment of early-stage non-small cell lung cancer (NSCLC) yields highest expectations for recovery. However, the frequency of further disease progression remains high since micro-metastatic disease may be undetected by conventional diagnostic methods. We test the presence and prognostic impact of circulating tumor cells (CTCs) in peripheral blood (PB), tumor-draining pulmonary blood (TDB) and bone marrow (BM) samples from NSCLC patients. Methods: The presence of circulating/disseminated tumor cells (CTCs/DTCs) was detected by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis in PB, TDB and BM samples before surgery in 119 stage IA-IIIA NSCLC patients (Clinical Trial NS10285). Results: NSCLC patients with the presence of carcinoembryonic antigen (CEA) mRNA-positive CTCs/DTCs in TDB and BM had significantly shorter cancer-specific survival (CSS) (P<0.013, resp. P<0.038). Patients with the presence of epithelial cellular adhesion molecule (EpCAM) mRNA-positive CTCs in TDB samples had significantly shorter CSS and disease-free survival (DFS) (P<0.031, resp. P<0.045). A multivariate analysis identified the presence of CEA mRNA-positive CTCs in the PB as an independent negative prognostic factor for DFS (P<0.005). No significant correlation of CTCs/DTCs presence and other prognostic factors was found. Conclusions: In NSCLC patients undergoing radical surgery, the presence of CEA and EpCAM mRNA-positive CTCs/DTCs is associated with poorer survival.

Predictive and Prognostic Value of DNA Damage Response Associated Kinases in Solid Tumors.

Dysfunctional DNA repair with subsequent genome instability and high mutational burden represents a major hallmark of cancer. In established malignant tumors, increased DNA repair capacity mediates resistance to DNA-damaging therapeutics, including cytotoxic drugs, radiotherapy, and selected small molecules including inhibitors of poly (ADP-ribose) polymerase (PARP), Ataxia Telangiectasia Mutated (ATM), ataxia telangiectasia and Rad3-related protein (ATR), and Wee1 kinase (Wee1). In addition, DNA repair deficiency is not only associated with sensitivity to selected anticancer drugs, but also with increased mutagenicity and increased neoantigen load on tumor cells, resulting in increased immunogenicity and improved response to CTLA4- or PD-(L)1 targeting monoclonal antibodies. DNA damage response (DDR) is composed of complex signalling pathways, including the sensing of the DNA damage, signal transduction, cellular response pathways to DNA damage, and activation of DNA repair. DNA double strand breaks (DSBs) are the most dangerous form of DNA damage. Tumor cells are characterised by frequent accumulation of DSBs caused by either endogenous replication stress or the impact of cancer treatment, most prominently chemotherapy and radiotherapy. Therefore, response of cancer cells to DSBs represents a crucial mechanism for how tumors respond to systemic treatment or radiotherapy, and how resistance develops. Ample clinical evidence supports the importance of DDR associated kinases as predictive and prognostic biomarkers in cancer patients. The ATM-CHK2 and ATR-CHK1-WEE1 pathways initiate DNA DSB repair. In the current review, we focus on major DDR associated kinases including ATM, ATR, CHK1, CHK2, and WEE1, and discuss their potential prognostic and predictive value in solid malignancies.

Prognostic value of tumor-infiltrating lymphocytes (TILs) and their association with PD-L1 expression and DNA repair protein RAD51 in patients with resected non-small cell lung carcinoma.

OBJECTIVES: DNA repair proteins have emerged as potential predictors for immunotherapy response alongside PD-L1 expression, tumor-infiltrating lymphocytes (TILs) and tumor mutational burden. We analyzed expression of PD-L1, TILs count and expression of the homologous recombination (HR) protein RAD51, as potential prognostic factors in patients with resected non-small-cell lung carcinoma (NSCLC). MATERIALS AND METHODS: Discovery set included 96 NSCLC patients from the University Hospital Olomouc (Czech Republic) and a replication set included 1109 NSCLC patients from University Hospital Zurich (Switzerland). Tissue microarrays (TMAs) were stained using the automated staining platform Ventana Benchmark Ultra with antibodies against RAD51,CD3, CD8, CD68 and PD-L1. RESULTS: Loss of nuclear RAD51 protein was associated with high TILs (r=-0.25, p = 0.01) and PD-L1 status (10.6 vs. 2.4 %, p = 0.012) in patients receiving neoadjuvant chemo-/radiotherapy (CT/RT). In silico analysis from the TCGA data set showed a negative relationship between RAD51 mRNA expression and CD45 (r = ‒0.422, p < 0.0001), CD68 (r = ‒0.326, p < 0.001), CD3 (r = ‒0.266, p < 0.001) and CD8 (r = ‒0.102, p < 0.001). RAD51 low/PD-L1 high patients were clustered as separate entity in the replication set and in TCGA dataset. High TILs status was significantly associated with improved OS in the replication set (unadjusted HR = 0.57, 95 % CI 0.42-0.76, p < 0.001). Similar results have been seen for CD3, CD8 and CD68. CONCLUSIONS: In conclusion, RAD51 nuclear loss is weakly associated with increased TILs and high PD-L1 at the time of surgery in curatively resected NSCLC and after prior exposure to neoadjuvant chemo- or radiotherapy. Both high TILs and RAD51 nuclear loss were confirmed as independent prognostic factors in curatively resected NSCLC.

Tumor autophagy is associated with survival outcomes in patients with resected non-small cell lung cancer.

OBJECTIVES: LC3A protein is associated with autophagosomes, and LC3A immunohistochemistry (IHC) is used for the detection of autophagy activity. The aim of this study was to assess the prognostic value of LC3A expression in patients with resected non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: We used tissue microarrays (TMAs) constructed from 116 resected stage IB-III NSCLC patients. Standard immunohistochemistry was performed on formalin-fixed paraffin-embedded tissue sections using antibody against LC3A autophagic potein. Stained slides were scanned by Olympus dotSlide Digital Virtual Microscopy System (Japan) and the LC3A staining was evaluated digitally. Groups were compared using the Mann Whitney U test, and correlations were assessed using Spearman's rank test. Survival was calculated using Kaplan-Meier analysis. Primary study endpoint was overall survival (OS), secondardy study endpoint disease-free survival (DFS). Cut-off optimization for LC3A prognostic value was performed using the "cut-off finder' 'software (Charite, Berlin, Germany). In addition, the Kaplan Meier plotter (KmPlot) was used to assess the relationship between LC3A mRNA expression and clinical outcome (OS and DFS) in patients with NSCLC. RESULTS: From 116 patients, 88 tissue samples were available for final examination. No significant association was found between LC3A staining and other clinicopathological variables, including tumor grade, stage and histological subtype. A higher number of LC3A stone-like structures (SLSs) (>20), was significanly associated with poor OS (HR = 2.27, p = 0.011) and DFS (HR = 2.27, p = 0.003). A significant association between high LC3A mRNA and both a worse OS and worse DFS was found by KMPlot analysis in patients with stage I-III NSCLC. CONSLUSION: This retrospective study suggests that SLSs as assessed by LC3A IHC as well as LC3A mRNA expression has a clinically relevant negative prognostic value in patients with resected NSCLC, and should be further investigated.

Real life adjuvant chemotherapy uptake and survival in patients with non-small cell lung cancer after complete resection.

OBJECTIVES: Adjuvant chemotherapy (AC) in non-small cell lung cancer (NSCLC) has become a standard of care in patients with stages IIA, IIB, and IIIA after complete tumor resection. Utilization and outcome of AC in routine practice is described in a few studies, with non-conclusive results. MATERIALS AND METHODS: This retrospective study included consecutive patients with NSCLC who underwent curative-intent surgery. Data of AC uptake in stages IB (tumor of ≥4 cm in diameter), II, and IIIA, and reasons of AC omission were evaluated according to medical records. Mortality risk among patients treated with surgery (only) and different types of AC in routine practice was compared. RESULTS: AC was applied to 79% of patients with stages IB (tumor of ≥4 cm in diameter), II, and IIIA, and was associated with an improved median of overall survival (HR = 0.69; 95% CI = 0.44-1.06). Significantly longer survival was achieved in the sub-group treated with platinum and oral vinorelbine (HR = 0.575, 95% CI = 0.339-0.974), and the longest survival was among patients treated with oral vinorelbine and cisplatin (HR = 0.371, 95% CI = 0.168-0.820). CONCLUSIONS: AC utilization should be based on co-operation between surgeons, pneumo-oncologists, and patients. Rational use of AC offers better survival in routine practice.

Prognostic and predictive value of loss of nuclear RAD51 immunoreactivity in resected non-small cell lung cancer patients.

OBJECTIVES: In response to DNA damage, recombination proteins are relocalized into sub-nuclear complexes that are microscopically detected as RAD51-containing nuclear foci. We aimed for assessing the prognostic and predictive value of loss of nuclear RAD51 immunoreactivity ('RAD51 loss') in 2 independent stage I to III non-small cell lung cancer (NSCLC) patient cohorts undergoing surgical resection and eventual perioperative chemo-/radiotherapy (CT/RT). MATERIALS AND METHODS: The discovery set included 69 evaluable patients (19 adenocarcinomas, ADC, 50 squamous cell carcinomas, SCC) from Palacky University Hospital, 45/69 (65.2%) with additional platinum-based CT. The replication set entailed 845 evaluable patients (446 ADC, 399 SCC) from University Hospital Zurich, 308/845 (36.5%) with platinum based CT or RT. RAD51 loss was defined as ≤20% of tumor cell nuclei having any nuclear RAD51 expression. We assessed the prognostic value of RAD51 loss in all patients and its predictive value in patients receiving CT/RT. RESULTS: RAD51 loss was observed in 40/69 (58.0%) and 439/845 (51.9%) evaluable tumors in the discovery and replication set, respectively (p=0.34). It was more frequent in ADC compared to SCC (57.2% vs 47.4%, p=0.003). RAD51 loss was significantly associated with worse OS in both the discovery (adjusted HR=2.39, p=0.039) and replication set (adjusted HR=1.31, p=0.008). The unfavourable prognostic effect of RAD51 loss seen in the overall population was not observed in patients receiving perioperative CT (adjusted HR=1.07, p=0.73) or perioperative RT (adjusted HR=1.05, p=0.82). CONCLUSION: RAD51 loss has an unfavourable prognostic impact in NSCLC patients undergoing curative surgical resection, but it may have a favourable predictive value in the subgroup of patients receiving perioperative platinum-based CT or RT, most likely as a consequence of deficient DNA repair.

Complex multilocular cystic lesion of rete testis, accompanied by smooth muscle hyperplasia, mimicking intratesticular Leydig cell neoplasm.

Non-neoplastic smooth muscle cell proliferation occurs under a variety of circumstances in many body organs. These abnormalities have been described as hypertrophy, hyperplasia or hamartomatous proliferations. In the male genital system, the excessive growth of smooth muscle in spermatic cord or paratesticular tissue is rare. In previously described cases, these lesions presented as masses but lacked the microscopic features of a neoplasm. We describe a complex multilocular cystic lesion composed of cystic transformation of the rete testis associated with smooth muscle proliferation mimicking intratesticular Leydig cell neoplasm. The lesion consists of three separate components: (1) cystic dilatation of the rete testis; (2) diffuse, interstitial smooth muscle proliferation with intraseptal expansion; and (3) extensive stroma with myxoid areas and scattered interstitial Leydig cells. These morphological findings, supported by a wide immunohistochemical panel, are consistent with cystic dilatation of the rete testis associated with smooth muscle hyperplasia, most probably of myoid origin. To the best of our knowledge, no similar complex lesion of the rete testis has yet been reported.

Correlation between BRCA1 expression and clinicopathological factors including brain metastases in patients with non-small-cell lung cancer.

BACKGROUND: Previously identified as a breast and ovarian cancer susceptibility gene, BRCA1 has gained major scientific interest as a potential prognostic and/or predictive marker for various tumors, including non-small-cell lung cancer (NSCLC), the leading cause of cancer related mortality worldwide. BRCA1 plays a central role in DNA damage response (DDR. It undergoes phosphorylation by various DDR kinases at different serine residues, of which ser1524 is known to be specifically phosphorylated by ATM in response to genotoxic stress. METHODS: We performed BRCA1 immunohistochemistry on several tissue microarrays (TMAs) of 113 early (I, II stage) and advanced (III, IV stage) NSCLCs, using MS110 antibody against the BRCA1 N-terminal and S1524 antibody against the phosphorylated form of BRCA1 protein at ser1524 (Abcam). Patients with III and IV stage disease were treated by adjuvant cisplatin-based chemotherapy. Staining results were correlated with overall survival (OS), disease free survival (DFS) and with the occurrence of brain metastases. RESULTS: BRCA1 S1524 nuclear positivity was significantly correlated with longer OS and DFS in stage I and II patients (P<0.05), while OS and DFS were shorter in S1524 positive stage III and IV patients (P<0.05). No significant correlation was found with brain metastases. CONCLUSION: The results show that BRCA1 phosphorylaton, at least in ser1524, differentiates the fate of early and advanced NSCLC as well as response to chemotherapy, but the underlying mechanisms are not completely understood. Detection of phosphorylated forms of BRCA1 might serve as a useful prognostic and predictive marker for patients with NSCLC.

The role of BRCA1 in non-small cell lung cancer.

BACKGROUND: BRCA1 (Breast cancer 1) was previously identified as a breast and ovarian cancer susceptibility gene, but recently gained a major scientific interest as a prognostic and/or predictive marker for various tumors, including non-small cell lung cancer (NSCLC), which is the leading cause of cancer related mortality in the world. We aimed to review the role of BRCA1 in NSCLC based on currently available literature. METHODS: We performed the literature search in Pubmed database, using key words: BRCA1, non small cell lung cancer, chemotherapy, drug resistance. Articles published in English were selected for review. RESULTS: Research papers are mainly focused on BRCA1 mRNA expression studies in response to DNA damaging chemotherapy. Several articles about genetic and epigenetic changes of BRCA1 in NSCLC were also available. CONCLUSIONS: BRCA1 is a multifunctional tumor supressor protein, which plays a key role in essential cellular processes and modulates the cellular response to cytotoxic chemotherapy. With the difference from breast and ovarian cancer, BRCA1 has no role in NSCLC cancerogenesis and mainly discussed as a promising genomic marker for customized chemotherapy in NSCLC patients.

A comparison of Direct sequencing, Pyrosequencing, High resolution melting analysis, TheraScreen DxS, and the K-ras StripAssay for detecting KRAS mutations in non small cell lung carcinomas.

BACKGROUND: It is mandatory to confirm the absence of mutations in the KRAS gene before treating metastatic colorectal cancers with epidermal growth factor receptor inhibitors, and similar regulations are being considered for non-small cell lung carcinomas (NSCLC) and other tumor types. Routine diagnosis of KRAS mutations in NSCLC is challenging because of compromised quantity and quality of biological material. Although there are several methods available for detecting mutations in KRAS, there is little comparative data regarding their analytical performance, economic merits, and workflow parameters. METHODS: We compared the specificity, sensitivity, cost, and working time of five methods using 131 frozen NSCLC tissue samples. We extracted genomic DNA from the samples and compared the performance of Sanger cycle sequencing, Pyrosequencing, High-resolution melting analysis (HRM), and the Conformité Européenne (CE)-marked TheraScreen DxS and K-ras StripAssay kits. RESULTS AND CONCLUSIONS: Our results demonstrate that TheraScreen DxS and the StripAssay, in that order, were most effective at diagnosing mutations in KRAS. However, there were still unsatisfactory disagreements between them for 6.1% of all samples tested. Despite this, our findings are likely to assist molecular biologists in making rational decisions when selecting a reliable, efficient, and cost-effective method for detecting KRAS mutations in heterogeneous clinical tumor samples.

The immunohistochemical expression of BNIP3 protein in non-small-cell lung cancer: a tissue microarray study.

Drug resistance is one of the reasons for chemotherapy failure in non-small-cell lung carcinoma (NSCLC). One of the major mechanisms of drug resistance is the inhibition of chemotherapy-induced apoptosis. Therefore, the study of novel cell death pathways could possibly enable us to overcome resistance to apoptosis in NSCLC. One of the non-caspase types of cell death is autophagy. BNIP3 protein, a Bcl-2 family member, highly expressed in some tumours, plays a key role in the induction of autophagy. In the present study, we investigated the immunohistochemical expression and subcellular localization of BNIP3 in a series of early- and late-stage non-small-cell lung carcinomas and normal bronchial tissues, and correlated this expression with the occurrence of metastasis and survival. BNIP3 was strongly expressed in the nucleus of cancer cells in 16/79 (20.3%) cases. This BNIP3 positivity did not correlate with histological grade, stage, histology type, metastatic potential, or expression of BNIP3 according to median values. No significant correlation was observed between the expression of BNIP3 and the overall survival of NSCLC patients (p = 0.55). Nor did we find any significant correlation between BNIP3 expression and the occurrence of site-specific metastasis (p = 0.85).