Simon Laban

Background Demographic development in rural and urban areas differs substantially. Demographics and access to specialized head and neck cancer centers may affect head and neck cancer patients' (HNCP) outcomes. Here, we compare epidemiological indicators and outcomes of HNCP in rural and urban Germany. Patients and Methods In a retrospective analysis of data from the Center for Cancer Registry Data (ZfKD) between 2002 and 2017, 212,920 HNCP were included. Incidence, demographics, travel distance to specialized centers, and ground values were compared between rural and urban areas with a focus on their association with patient outcomes. Results The mean age of HNCP was significantly higher in urban areas (mean difference = 1.4 years; p < 0.0001), but increased at a comparable rate ( p = 0.26) in rural and urban areas during the observation period. Gender imbalance was higher in rural areas (mean ratio of men/women: 4.1 vs. 3.1; p < 0.0001), but showed a comparable trend toward equilibration in both, rural and urban districts ( p = 0.46). The portion of HNCP of the entire HNCP population living in urban areas increased from 55.9% in the year 2002 to 76.4% in the year 2017. There was no significant difference or change in the ratio of advanced to low UICC stage during the observation period ( p = 0.26). However, travel distances to medical centers were higher in rural areas, especially ( p < 0.0001) in East Germany. Median survival of HNCP in rural areas was significantly lower than in urban areas (42 months [SEM = 0.7; CI: 40.5–43.5] vs. 54 months [SEM = 1.2; CI: 51.7–56.3]; p < 0.0001) in East Germany, whereas in West Germany no significant difference was observed (59 months [SEM = 0.8; CI: 57.4–60.6] vs. 60 months [SEM = 0.5; CI: 59.0–61.0]; p = 0.15). Conclusions Place of residence contributes to survival outcome of HNCP. Access to specialized care and socioeconomic factors could be improved in East Germany.

Constitutively active kinases play a crucial role in carcinogenesis, and their inhibition is a common target for molecular tumor therapy. We recently discovered the expression of two oncogenic isoforms of Bruton’s Tyrosine Kinase (BTK) in head and neck squamous cell carcinoma (HNSCC), Btk-p80 and BTK-p65. However, the precise role of BTK in HNSCC remains unclear. Analyses of a tissue microarray containing benign and malignant as well as inflammatory tissue samples of the head and neck region revealed the preferential expression of BTK-p80 in malignant tissue, whereas BTK-p65 expression was confirmed in over 80% of analyzed metastatic head and neck tumor cases. Therefore, processes associated with metastasis, like cancer stem cell (CSC) enrichment and the epithelial–mesenchymal transition (EMT), which in turn depend on an appropriate cytokine milieu, were analyzed. Treatment of HNSCC-derived cell lines cultured under 3D conditions with the BTK inhibitor AVL-292 caused reduced sphere formation, which was accompanied by reduced numbers of ALDH1A1+ CSCs as well as biological changes associated with the EMT. Moreover, we observed reduced NF-κB expression as well as altered NF-κB dependent pro-tumorigenic and EMT-associated cytokine release of IL-6, IFNγ, and TNFα when BTK activity was dampened. Therefore, an autocrine regulation of the oncogenic BTK-dependent process in HNSCC can be suggested, with BTK inhibition expected to be an effective treatment option for HNSCC.