Norbert Nass

Background:Head and neck squamous cell carcinomas (HNSCC) are often diagnosed in advanced stages with regional lymph node metastasis. L1CAM (L1 cell adhesion molecule) is known as a significant prognostic marker in solid tumors such as endometrial and colon carcinoma and is often associated with lymphovascular invasion and therefore poor prognosis. Here, we investigated the expression of L1CAM in HNSCC and evaluated its prognostic impact.Methods:L1CAM expression was determined by immunohistochemistry in a retrospective cohort of 232 HNSCC patients of all head and neck tumor locations. L1CAM expression was correlated with clinicopathological characteristics and its prognostic value evaluated for overall- and relapse-free survival.Results:L1CAM-staining was observed at the cell membrane and was most intense at the invasion front. Tumor size, TNM stage, and the risk factor alcohol consumption was linked to high L1CAM expression. L1CAM-status was highly associated with unfavorable outcome, for relapse free (RFS) as well as overall survival (OS). In subgroup analyses, L1CAM status was equally important for all subgroups. L1CAM status was less significant for outcome in lymph node metastasis-positive (N1) and higher TNM stage (III+IV) subgroups.Conclusions:The determination of L1CAM by immunohistochemistry could be a promising additional prognostic biomarker for the outcome of HNSCC, especially for lower TNM stages.

Purpose: Head and Neck squamous cell carcinomas (HNSCC) are often diagnosed in late stages with regional lymph node metastasis. L1CAM (L1 cell adhesion molecule) is known as a significant prognostic marker in solid tumours such as endometrial and colon carcinoma and is often associated with invasion into the lymphovascular space and therefore poor prognosis. Here, we investigated L1CAM´s expression in HNSCC and determined its prognostic value. Methods: We analyzed L1CAM expression by immunohistochemistry in a retrospective cohort of 233 HNCC patients of all head and neck locations. An immunoreactive score was developed and its association with clinic-pathological characteristics and its prognostic value evaluated for overall and relapse free survival. Results: L1CAM-staining was observed at the cell membrane and was most intense at the invasion front. Tumor size, UICC stage and the risk factor alcohol-consumption could be linked to high L1CAM expression. L1CAM-status was highly associated with unfavorable outcome, for relapse free (RFS) as well as overall survival (OS). In subgroup analyses, L1CAM status was equally important for all subgroups. Only for lymph node metastasis positive (N1) and higher UICC stage (3 + 4) subgroups, L1CAM-status was not significant for outcome. Conclusions: The determination of L1CAM by immunohistochemistry could be a promising additional prognostic biomarker for the outcome of HNSCC for the major anatomical sites oral cavity, oropharynx, hypopharynx and larynx.

Colorectal cancer (CRC) is a significant global health concern, ranking as the third most frequently diagnosed cancer and the second leading cause of cancer-related deaths. Advances in screening, such as the implementation of liquid biopsies (LB), have improved early detection, thus enhancing survival rates. This review summarizes the multifaceted nature of CRC, focusing on its genetic background, the complex tumor microenvironment, and the influence of gut microbiota, nutrition, and metabolic alterations. The development of CRC is influenced by various risk factors, including age, genetics, chronic diseases, and lifestyle choices. The genetic heterogeneity of CRC defines distinct molecular subtypes, characterized by different treatment responses and patient prognoses. Chronic inflammation and dysbiosis in the gut microbiota further contribute to CRC pathogenesis. In addition, nutritional factors play a crucial role in CRC, affecting carcinogenesis and treatment efficacy through direct interaction with the immune system and microbiome. Current therapeutic strategies include surgical interventions, chemo- and radiotherapy, targeted therapies, immunotherapy as well as dietary interventions, and microbiome modulation, highlighting the challenges posed by tumor heterogeneity and treatment resistance. In sum, a comprehensive understanding of CRC’s intrinsic and extrinsic drivers, including genetic, metabolic, and dietary influences, is essential for developing personalized treatment strategies and improving patient outcomes.

Objectives: Vascular endothelial growth factor (VEGF) regulates tumor vascularization in response to hypoxia and inflammatory signals. The polyphenol curcumin is supposed to interfere with inflammation-induced VEGF secretion and might therefore support anti-VEGF-based treatments. We aimed to investigate the interaction between curcumin and the inflammatory cytokine Interleukin-1β (IL-1β) for VEGF secretion in breast cancer cell lines representing major breast cancer subtypes. Methods: VEGF in cell cultures was detected by Western blot and enzyme-linked immunosorbent assay (ELISA). Kinase phosphorylation was investigated by Western blotting. Gene expressions were analyzed by correlation tests. VEGF was evaluated in a retrospective breast cancer cohort by immunohistochemistry. Survival analysis was performed by the Kaplan-Meier algorithm. Results: VEGF secretion and kinase signaling in response to IL-1β and curcumin varied significantly for the cell lines MCF-7 (Luminal A), SK-BR-3 (HER2/neu+), MDA-MB-231, and UACC-3199 (triple negative breast cancer). All cell lines increased VEGF secretion under hypoxia, but IL-1β increased VEGF secretion only in MCF-7 cells. Curcumin inhibited VEGF secretion in MDA-MB-231, but increased it in MCF-7 and UACC-3199 cells. Curcumin induced phosphorylation of extracellular signal-regulated kinase (ERK) and p38-mitogen-activated protein kinase (p38-MAPK). However, inhibitor experiments demonstrated that ERK was more important for VEGF secretion. In gene expression data from the METABRIC study, no clear correlation of hypoxia-induced factor (HIF1A), IL-1β, and VEGF mRNA expression was observed; however, a suggested crosstalk of hypoxia and inflammatory pathways was observed. Conclusion: These dissimilar responses of breast cancer cell lines suggest that therapy efficiency with anti-VEGF, anti-IL-1β, or curcumin will also vary within breast cancers.

Cold shock domain (CSD) proteins, such as YB-1, play a crucial role in the regulation of transcription, mRNA stability, and translation. Consequently, YB-1 is implicated in processes such as cell differentiation, oncogenesis and oxidative stress response. The development of the eye is a complex process that involves the differentiation of numerous highly specialized cell types. We hypothesized that YB-1 is involved in both eye development and stress defense mechanisms. As an initial step, we investigated the expression of YB-1 during the embryology of the mouse eye. YB-1 mRNA could be detected by RT-PCR and sequencing the PCR product in retinal tissue of adult mice. To elucidate the expression pattern of YB-1 protein during mouse eye development, we analyzed its expression in the developing mouse eye at embryonic day 13 (E13), E15, E18 and postnatal day 14 (P14) using immunohistochemistry. Expression of the YB-1 protein was detected in all retinal cells, as well as in the corneal and lens epithelial cells, throughout all stages of eye development examined. These findings suggest that YB-1 could have a significant role in the eye, potentially related to development and differentiation.

Background: VEGF regulates tumor vascularization in response to hypoxia and inflam-matory signals while curcumin is anti-inflammatory. We investigated this interaction in breast cancer cell lines and gene expression databases. Methods: VEGF in cell cultures was detected by ELISA. Kinase activation was investigated by Western blotting. Gene ex-pression databases were analyzed by correlation tests. Results: VEGF secretion and kinase signaling in response to IL-1β and curcumin varied significantly for the cell lines. All cell lines increased VEGF secretion under hypoxia, but IL-1β increased VEGF secretion only in MCF-7 cells. VEGF secretion was inhibited by curcumin in MDA-MB-231 cells but in-creased in MCF-7- and UACC-3199 cells. Inhibitor experiments in MCF-7 cells demon-strated that curcumin-induced ERK- phosphorylation was important for VEGF secretion. In a retrospective cohort, VEGF detected by immunohistochemistry correlated with ductal- versus lobular morphology but showed no prognostic significance. Gene expression data of the METABRIC study showed highest VEGFA mRNA expression in triple negative breast cancer. Analysis of HIF-, NF-kB-signaling and VEGF expression on the mRNA level showed no clear correlation but suggested crosstalk of these pathways. Conclusion: These dissimilar responses of breast cancer cell lines suggest that therapy efficiency with an-ti-VEGF, anti-IL-1β or curcumin will also vary within breast cancers.

Background: Breast cancer is the most common cancer in women worldwide. Triple-negative breast cancer (TNBC) is especially aggressive and associated with high metastasis. The aetiology of TNBC is heterogeneous and characterised by multiple different mutations that amongst others cause constitutive and dysregulated MAPK and PI3K signalling. Additionally, in more than 50% of TNBC patients, the epidermal growth factor receptor (EGFR) is overexpressed and constitutively active. The multi-site docking protein Grb2-associated binder 1 (Gab1) is a central signalling hub that connects MAPK and PI3K signalling. Methods: Expression and activation of members of the Gab1/PI3K/MAPK signalling network were assessed in cells from different breast cancer subtypes. Influence of short- and long-term inhibition of EGFR, MAPK and PI3K on the activation of the Gab1/PI3K/MAPK signalling network as well as on cell viability, proliferation and migration was determined. Additionally, cellular localisation of Gab1 and Gab1 variants in naive cells and cells treated with the above-mentioned inhibitors was investigated. Results: We show that, activation of the Gab1/PI3K/MAPK signalling network is heterogeneous between different breast cancer subtypes. Gab1 phosphorylation and plasma membrane recruitment of Gab1 are dysregulated in the EGFR^high TNBC cell line MDA-MB-468. While the Gab1/MAPK/PI3K signalling network follows canonical Gab1 signalling in naive MDA-MB-468 cells, Gab1 signalling is changed in cells that acquired resistance towards MAPK and PI3K inhibition. In resistant cells, Gab1 is not located at the plasma membrane despite strong activation of PI3K and MAPK. Furthermore, Gab1 tyrosine phosphorylation is uncoupled from plasma membrane recruitment. Conclusion: Our study indicates that Gab1 signalling changes fundamentally during the acquisition of resistance to pharmacological inhibitors. Given the molecular heterogeneity between breast cancer subtypes, the detailed understanding of dysregulated and aberrant signalling is an absolute necessity in order to develop personalised therapies for patients with TNBC.

Drug resistance is a common cause of therapy failure in head and neck squamous cell carcinoma (HNSCC). One approach to tackling it is by targeting fundamental cellular processes, such as translation. The eukaryotic translation initiation factor 2α (EIF2α) is a key player in canonical translation initiation and integrates diverse stress signals; when phosphorylated, it curbs global protein synthesis. This study evaluates EIF2α expression and phosphorylation in HNSCC. A small-molecule inhibitor of EIF2α dephosphorylation, salubrinal, was tested in vitro, followed by viability assays, flow cytometry, and immunoblot analyses. Patient-derived 3D tumor spheres (PD3DS) were cultured with salubrinal and their viability assessed. Lastly, salubrinal was evaluated with standard-of-care chemotherapeutics. Our analysis of RNA and proteomics data shows elevated EIF2α expression in HNSCC. Immunohistochemical staining reveals increasing EIF2α abundance from premalignant lesions to invasive and metastatic carcinoma. In immunoblots from intraoperative samples, EIF2α expression and steady-state phosphorylation are higher in HNSCC than in neighboring normal tissue. Inhibition of EIF2α dephosphorylation decreases HNSCC cell viability and clonogenic survival and impairs the G₁/S transition. Salubrinal also decreases the viability of PD3DS and acts synergistically with cisplatin, 5-fluorouracil, bleomycin, and proteasome inhibitors. Our results indicate that pharmacological inhibition of EIF2α dephosphorylation is a potential therapeutic strategy for HNSCC.

Editorial: Hormones and receptors in breast cancer