Zellen der Tumorfront: Ein mögliches therapeutisches Ziel bei der Behandlung von Kopf-Hals-Karzinomen?

The integration of differentially expressed genes based on multiple microarray datasets for prediction of the prognosis in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a common human malignancy. However, its pathogenesis and prognostic information are poorly elucidated. In the present study, we aimed to probe the most significant differentially expressed genes (DEGs) and their prognostic performance in OSCC. Multiple microarray datasets from the Gene Expression Omnibus (GEO) database were aggregated to identify DEGs between OSCC tissue and control tissue. Least absolute shrinkage and selection operator (LASSO) Cox model was constructed to determine the prognostic performance of the aggregated DEGs based on The Cancer Genome Atlas (TCGA) OSCC cohort. Ten datasets with 341 OSCC samples and 283 control samples were included. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment revealed that the integrated DEGs were enriched in the IL-17 signaling pathway, viral protein interactions with cytokines and cytokine receptors, and amoebiasis, among others. Our LASSO Cox model was able to discriminate two groups with different overall survival in the training cohort and test cohort (p < 0.001). The time-dependent receiver operating characteristic (ROC) curve revealed that the area under the curve (AUC) values at one year, three years, and five years were 0.831, 0.898, and 0.887, respectively. In the testing cohort, the time-dependent ROC curve showed that the AUC values at one year, three years, and five years were 0.696, 0.693, and 0.860, respectively. Our study showed that the integrated DEGs of OSCC might be applicable in the evaluation of prognosis in OSCC. However, further research should be performed to validate our findings.

Effect of tumor microenvironment on pathogenesis of the head and neck squamous cell carcinoma: a systematic review

The tumor microenvironment (TME) is comprised of many different cell populations, such as cancer-associated fibroblasts and various infiltrating immune cells, and non-cell components of extracellular matrix. These crucial parts of the surrounding stroma can function as both positive and negative regulators of all hallmarks of cancer development, including evasion of apoptosis, induction of angiogenesis, deregulation of the energy metabolism, resistance to the immune detection and destruction, and activation of invasion and metastasis. This review represents a summary of recent studies focusing on describing these effects of microenvironment on initiation and progression of the head and neck squamous cell carcinoma, focusing on oral squamous cell carcinoma, since it is becoming clear that an investigation of differences in stromal composition of the head and neck squamous cell carcinoma microenvironment and their impact on cancer development and progression may help better understand the mechanisms behind different responses to therapy and help define possible targets for clinical intervention.

[Cancer stem cell phenotypes and miRNA: therapeutic targets in head and neck squamous cell carcinoma]

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. HNSCC is caused by persistent high-risk human papillomavirus (HR-HPV) infection or excessive consumption of alcohol or tobacco. The persistently low survival rates result from local recurrences and metastases, which are probably caused by so-called tumor stem cells (TSCs). The epithelial-mesenchymal transition (EMT) or transformation is a key event in metastasis initiation and is being increasingly associated with TSCs.

OBJECTIVES

This review describes new therapeutic targets in HNSCC, focusing on the TSC hypothesis and EMT regulation.

MATERIALS AND METHODS, RESULTS

TSCs and EMT are regulated directly and indirectly via transcription factors and microRNAs (miRNAs). These miRNAs regulate multiple cellular processes and may serve as new therapeutic targets, whose modulation could increase the effectiveness of HNSCC treatments. Post-transcriptionally, miRNAs regulate transcription factors associated with EMT (ZEB1/2, EZH2, Bmi-1), tumor suppressors (p53), TSC markers (ALDH, CD44, EpCAM, p63) and both epithelial (E-cadherin) and mesenchymal markers (vimentin).

CONCLUSION

Alterations in HNSSC TSC miRNA expression before and after chemotherapy could potentially serve as a therapeutic control. In the long term, knowledge of a patient's individual protein expression pattern may permit application of specific chemotherapy. Such individualized therapy might prohibit the development of metastases and potentially unresectable recurrences with a high resistance to radiation and chemotherapy, thus improving the prognosis in HNSCC patients.