The aim of this study was to evaluate the mutation profile of BRAF wild-type craniopharyngiomas and ameloblastomas. Pre-screening by immunohistochemistry and pyrosequencing for identifying BRAF wild-type tumors was performed on archived specimens of ameloblastic tumors (n = 20) and craniopharyngiomas (n = 62). Subsequently, 19 BRAF wild-type tumors (nine ameloblastic tumors and ten craniopharyngiomas) were analyzed further using next-generation sequencing (NGS) targeting hot spot mutations of 22 cancer-related genes. Thereby, we found craniopharyngiomas mainly CTNNB1 mutated (8/10), including two FGFR3/CTNNB1-double mutated tumors. Ameloblastic tumors were often FGFR2 mutated (4/9; including one FGFR2/TP53/PTEN-triple mutated case) and rarely CTNNB1/TP53-double mutated (1/9) and KRAS-mutated (1/9). In the remaining samples, no mutation could be detected in the 22 genes under investigation. In conclusion, mutation profiles of BRAF wild-type craniopharyngiomas and ameloblastomas share mutations of FGFR genes and have additional mutations with potential for targeted therapy.

Paediatric chronic myeloid leukaemia (ped-CML) is rare and ped-CML with fibre accumulation in the bone marrow (MF) is thought to be even rarer. In adults (ad-CML), fibrosis represents an adverse prognostic factor. So far, the pro-fibrotic changes in the bone marrow microenvironment have not been investigated in detail in ped-CML. From a total of 66 ped-CML in chronic phase, biopsies were analysable and 10 had MF1/2 (MF1, n=8/10; MF2, n=2/10). We randomly selected 16 ped-CML and 16 ad-CML cases with and without fibrosis (each n=8) as well as 18 non-neoplastic controls. Bone marrow samples were analysed with a real-time PCR-based assay (including 127 genes for paediatric cases) and by immunohistochemistry. We found increased expression of megakaryocytic genes in ped-CML. The number of megakaryocytes and pro-platelets are increased in CML patients, but the most significant increase was noted for ped-CML-MF1/2. Anti-fibrotic MMP9 expression was lower in children than in adults. Cell mobilisation-related CXCL12 was decreased in young and adult patients with CML but not the corresponding receptor CXCR4. In summary, fibre accumulation in ped-CML-MF1/2 is associated with increased megakaryocytic proliferation and increased interstitial pro-platelet deposition. Deregulated expression of matrix-modulating factors shifts the bone marrow microenvironment towards fibrosis.

It is known that human papillomavirus (HPV) infection can cause squamous cell neoplasms at several sites, such as cervix uteri carcinoma and oral squamous carcinoma. There is little information on the expression of HPV and its predictive markers in tumours of the major and minor salivary glands of the head and neck. We therefore assessed oral salivary gland neoplasms to identify associations between HPV and infection-related epidermal growth factor receptor (EGFR), cyclin-dependent kinase inhibitor 2A (CDKN2A/p16) and tumour protein p53 (TP53). Formalin-fixed, paraffin-embedded tissue samples from oral salivary gland carcinomas (n=51) and benign tumours (n=26) were analysed by polymerase chain reaction (PCR) analysis for several HPV species, including high-risk types 16 and 18. Evaluation of EGFR, CDKN2A, TP53 and cytomegalovirus (CMV) was performed by immunohistochemistry. Epstein–Barr virus (EBV) was evaluated by EBV-encoded RNA in situ hybridisation. We demonstrated that salivary gland tumours are not associated with HPV infection. The expression of EGFR, CDKN2A and TP53 may be associated with tumour pathology but is not induced by HPV. CMV and EBV were not detectable. In contrast to oral squamous cell carcinomas, HPV, CMV and EBV infections are not associated with malignant or benign neoplastic lesions of the salivary glands.

Chronic histiocytic intervillositis of the placenta (CHI) shows monocytic/histiocytic infiltration of the intervillous space. Placental malaria has a CHI-like histopathology and induces an aberrant expression of Toll-like receptors (TLR) 3, 7-9. We hypothesized that, similar to placental malaria, CHI could be associated with increased TLR expression. TLR1-10 and other inflammation-associated factors were analyzed by real-time PCR and immunohistochemistry. A total of 31 formalin-fixed and paraffin-embedded placenta samples were evaluated: CHI (n = 9), and for control purposes, villitis of unknown etiology (VUE, n = 8) and placentas without inflammation (n = 14). CHI shows increased expression of monocytic TLR1, a receptor which is involved in bacterial lipopolysaccharide (LPS)-induced inflammation. This could indicate a TLR1-mediated immune mechanism in the placenta (e.g. triggered by transient, clinically inapparent maternal bacteraemia) which leads to massive monocytic/histiocytic accumulation in the intervillous space. The increased expression of TLR1 with no increased expression of TLR3 and TLR7-9 is different from that in malaria.

The only curative therapy for primary myelofibrosis (PMF) is allogeneic stem cell transplantation (ASCT). However, although we know that patients can benefit from ASCT, we do not know the extent of the changes of the expression profile of cytokines and matrix modulation factors. In this first systematic analysis, we evaluated the expression profile of 103 factors before and after transplantation to identify potential biomarkers. The expression of fibrosis-, inflammation-, and angiogenesis-associated genes was analyzed in a total of 52 bone marrow biopsies: PMF patients (n = 14) before and after ASCT and, for control purposes, post-ASCT multiple myeloma patients (n = 14) and non-neoplastic hematopoiesis (n = 10). In post-ASCT PMF cases, decreased expression of tissue inhibitor of metalloproteinases (TIMP) and platelet-derived growth factor alpha (PDGFA) correlated with bone marrow remodeling and hematological remission. Expression of several other matrix factors remained at high levels and may contribute to post-ASCT remodeling. This is the first systematic analysis of cytokine expression in post-ASCT PMF bone marrow that shows that normalization of bone marrow microenvironment is paralleled by decreased expression of TIMP and PDGFA.