Recently identified biomarkers that promote lymph node metastasis in head and neck squamous cell carcinoma

MMP-9 and CCR7 as Possible Predictors of Lymph Node Metastasis in Laryngeal Squamous Cell Carcinoma

Background & Objective

The expression of matrix metalloproteinase-9 (MMP-9) and chemokine receptor 7 (CCR7) is significantly associated with tumor invasion and metastasis. Little is known regarding the potential of these markers in predicting cancer metastasis in Laryngeal Squamous Cell Carcinoma (LSCC). Therefore, this study aimed to dissect the potential of these markers in predicting the lymph node metastasis in LSCC patients.

Methods

Sixty tissue samples were obtained from the patients diagnosed pathologically with LSCC who underwent partial or total laryngectomy. The expression of MMP-9 and CCR7 was measured using the immunohistochemistry staining in the tissue samples of LSCC patients. The ROC (receiver operating characteristic) curve was used to determine the most significant cut-off points of expression according to the highest sensitivity and specificity of both the markers to predict the lymph node metastasis in LSCC. Then, the relationship between the clinicopathology features and the expression of MMP-9 and CCR7 was evaluated.

Results

The expression of both MMP-9 and CCR7 was significantly correlated with the lymph node metastasis in LSCC (P<0.001). Furthermore, CCR7 expression exhibited the highest prediction accuracy (AUC 95.7%) and sensitivity (100%) in predicting the lymph node metastasis in LSCC compared to that of MMP-9 (AUC 92.9%, sensitivity 90%). We also found that patients with larger tumor size (> 4 cm) had significantly higher expression of MMP-9 and CCR7 (P<0.002 and P<0.001, respectively). The Elevated expression level of CCR7 statistically correlated with higher MMP-9 expression (P<0.001).

Conclusion

MMP-9 and CCR7 might be beneficial as predictors of lymph node metastasis in LSCC patients.

Deep learning assisted contrast-enhanced CT-based diagnosis of cervical lymph node metastasis of oral cancer: a retrospective study of 1466 cases

OBJECTIVES

Lymph node (LN) metastasis is a common cause of recurrence in oral cancer; however, the accuracy of distinguishing positive and negative LNs is not ideal. Here, we aimed to develop a deep learning model that can identify, locate, and distinguish LNs in contrast-enhanced CT (CECT) images with a higher accuracy.

METHODS

The preoperative CECT images and corresponding postoperative pathological diagnoses of 1466 patients with oral cancer from our hospital were retrospectively collected. In stage I, full-layer images (five common anatomical structures) were labeled; in stage II, negative and positive LNs were separately labeled. The stage I model was innovatively employed for stage II training to improve accuracy with the idea of transfer learning (TL). The Mask R-CNN instance segmentation framework was selected for model construction and training. The accuracy of the model was compared with that of human observers.

RESULTS

A total of 5412 images and 5601 images were labeled in stage I and II, respectively. The stage I model achieved an excellent segmentation effect in the test set (AP₅₀-0.7249). The positive LN accuracy of the stage II TL model was similar to that of the radiologist and much higher than that of the surgeons and students (0.7042 vs. 0.7647 (p = 0.243), 0.4216 (p < 0.001), and 0.3629 (p < 0.001)). The clinical accuracy of the model was highest (0.8509 vs. 0.8000, 0.5500, 0.4500, and 0.6658 of the Radiology Department).

CONCLUSIONS

The model was constructed using a deep neural network and had high accuracy in LN localization and metastasis discrimination, which could contribute to accurate diagnosis and customized treatment planning.

KEY POINTS

• Lymph node metastasis is not well recognized with modern medical imaging tools. • Transfer learning can improve the accuracy of deep learning model prediction. • Deep learning can aid the accurate identification of lymph node metastasis.

Machine learning in dental, oral and craniofacial imaging: a review of recent progress

Artificial intelligence has been emerging as an increasingly important aspect of our daily lives and is widely applied in medical science. One major application of artificial intelligence in medical science is medical imaging. As a major component of artificial intelligence, many machine learning models are applied in medical diagnosis and treatment with the advancement of technology and medical imaging facilities. The popularity of convolutional neural network in dental, oral and craniofacial imaging is heightening, as it has been continually applied to a broader spectrum of scientific studies. Our manuscript reviews the fundamental principles and rationales behind machine learning, and summarizes its research progress and its recent applications specifically in dental, oral and craniofacial imaging. It also reviews the problems that remain to be resolved and evaluates the prospect of the future development of this field of scientific study.

Survivin Expression in Metastatic and Nonmetastatic Oral Squamous Cell Carcinoma: A Comparative Study

Aim:

Survivin is a multifunctional protein chiefly involved in apoptosis and cell cycle regulation. Increased expression of survivin in tumors and fetal tissue determines its antiapoptotic activity. The aim of the study is to identify the immunoexpression of survivin in metastatic and nonmetastatic oral squamous cell carcinoma (OSCC) and also to evaluate and compare the expression of survivin in metastatic and nonmetastatic OSCC of buccal mucosa.

Materials and Methods:

In total, 40 histopathologically proven cases of OSCC, including 20 metastatic and 20 nonmetastatic cases, are selected. Among the 20 metastatic and nonmetastatic cases, 10 well-differentiated and 10 moderately differentiated squamous cell carcinoma cases were included and were subjected to immunohistochemical staining for survivin expression. The results were analyzed by SPSS version 11.5 using chi-square test.

Results:

The expression of survivin in metastatic and nonmetastatic tumors is 15%–70% and 15%–60%, respectively. When comparing the cases of moderately differentiated squamous cell carcinoma in metastatic and nonmetastatic tumors, 70% cases show moderate staining intensity.

Conclusion:

The survivin expression was comparatively high in metastatic OSCC. Also based on the aforementioned results, survivin expression was high in increasing grades of OSCC.

Development and validation of prognostic index based on autophagy-related genes in patient with head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers worldwide, accounting for almost 50% of all malignancies in developing nations. Autophagy plays a vital role in cancer initiation, malignant progression, and resistance to treatment. However, autophagy-related gene sets have rarely been analyzed in HNSCC. Hence, it is necessary to assess its clinical and pathological significance in a larger cohort of patients with HNSCC. The purpose of this study was to establish a novel autophagy-related prognostic marker for HNSCC. We screened 232 autophagy-related genes (ARGs) and identified 38 differentially expressed ARGs in The Cancer Genome Atlas (TCGA) cohorts. The prognosis-related ARGs signature, established using the univariate and multivariate Cox proportional regression models, consists of 10 ARGs that could divide patients into high-risk and low-risk groups. Survival analysis indicated that patients in the high-risk group had dramatically shorter overall survival compared with their low-risk counterparts. Cox regression analysis further confirmed the independent prognostic value of the autophagy-related signature, and the area under the receiver operating characteristic curve of the combined prognostic model was 0.722. Finally, the efficacy of autophagy-related signature was also validated by an independent cohort from the Gene Expression Omnibus (GEO) database. Collectively, we successfully constructed a novel autophagy-related signature for the prediction of prognosis in patients with HNSCC.

Silencing of long non-coding RNA LINC00520 promotes radiosensitivity of head and neck squamous cell carcinoma cells

Aberrant expression of LINC00520 has been identified in head and neck squamous carcinoma (HNSCC). However, its function in the radiosensitivity of HNSCC remain unclear. Herein, we aimed to define the role LINC00520 in the radiosensitivity of HNSCC and identify the underlying mechanism. Tumour tissues and adjacent normal tissue were collected from HNSCC patients. Differentially expressed genes (DEGs) in HNSCC tumour were obtained from the cancer genome atlas (TCGA) database. Interactions between LINC00520 and miR-195, homeobox A10 (HOXA10) and miR-195 were evaluated by dual-luciferase reporter gene assay, RNA Immunoprecipitation (RIP), and RNA pull-down assay. The effects of LINC00520/miR-195/HOXA10 on radiosensitivity of HNSCC were analysed in the evaluation of radiotherapy outcome. Cell proliferation, invasion, migration, and apoptosis of HNSCC cells were accessed via gain- and loss-of-function approaches. Tumour xenograft in nude mice was conducted in order to confirm the results in vivo. LINC00520 was upregulated while miR-195 was downregulated in HNSCC cells and tissues. Silencing LINC00520 or overexpressing miR-195 promoted radiosensitivity and inhibited cell proliferation, invasion, migration, and apoptosis in HNSCC. Moreover, these in vitro findings were reproduced in vivo in human HNSCC xenograft in nude mice. LINC00520/miR-195/HOXA10 is involved in the radiosensitivity mediation, providing potential therapeutic target for HNSCC treatment.

MicroRNA profiling of pancreatic ductal adenocarcinoma (PDAC) reveals signature expression related to lymph node metastasis

Lymph node (LN) metastasis occurs frequently in pancreatic ductal adenocarcinoma (PDAC), representing an advanced disease stage and independently predicting patient survival. Current nodal staging is inadequate preoperatively and even less so postoperatively, and molecular biomarkers are needed to improve prognostication and selection of therapy. Recent data have suggested important roles of miRNAs in PDAC tumorigenesis and progression. The aim of the present study was to identify miRNA expression signature for nodal spread in PDAC patients. Using PDAC human tissue specimens, we identified 39 miRNAs which were differently expressed in LN positive compared to LN negative PDAC samples. Of them, six miRNAs have been reported to play a role in cancer invasion and metastasis. A high versus low six- miRNA signature score was predictive of LN metastasis in the PDAC validation cohort. We demonstrated a similar expression pattern of four out of the six miRNAs in the plasma of PDAC patients. The results of our in-vitro studies revealed that miR-141 and miR-720 are involved in the process of epithelial to mesenchymal-transition in PDAC. These miRNAs significantly inhibited in vitro proliferation, migration and invasion of PDAC cells as evidence by gain- and loss- of function studies, specifically, via ZEB-1 and TWIST1 transcription factors, as well as through the activation of the MAP4K4/JNK signaling pathway.

Pathway based prognostic gene expression profile of buccal and gingivo-buccal oral squamous cell carcinoma in smokeless tobacco chewers

BACKGROUND

The objective was to study comprehensive mRNA expression profiles of buccal mucosa oral squamous cell carcinoma (OSCC-BM) and gingivo-buccal OSCC (OSCC-GB) in smokeless tobacco chewers to understand the biological behavior of OSCC at these specific sites and identify diagnostic and prognostic markers.

METHODS

High throughput RNA sequencing transcriptome of fresh buccal mucosa (4 samples) and gingivo-buccal (4 samples) OSCC with normal oral mucosa (3 samples) was performed on Illumina NextSeq500 paired end sequencing with 75x2bp.

RESULTS

In the comparison between OSCC and normal, there were 402 differentially expressed genes (DEGs); between OSCC-BM and normal, there were 467 DEGs; and between OSCC-GB and normal oral tissue, there were 608 DEGs. Pathway-based analysis of gene expression was done. The inflammation mediated by chemokine and cytokine signaling pathway had the maximum gene hits.

CONCLUSIONS

FZD2 and its interactions with the cadherins have a role in invasion and metastasis. immunosurveillance is evident in OSCC-GB with the downregulation of CADM1.

Survivin is a negative prognostic factor in malignant pleural effusion

BACKGROUND

Survivin is a well-known member of the inhibitor of apoptosis family, and has been related to increased tumour aggressivity, both in tissue and in pleural fluid.

OBJECTIVES

In patients with malignant pleural effusion, we sought to investigate the changes in pleural fluid survivin concentrations induced by talc instillation into the pleural space. Those changes were also examined in relation to pleurodesis outcome and patient survival.

METHODS

We investigated 84 patients with malignant pleural effusion who underwent talc pleurodesis. Of them, 32 had breast cancer, 25 lung cancer and 27 had mesothelioma. Serial samples of pleural fluid were obtained before thoracoscopy (baseline) and 24 hours thereafter.

RESULTS

Survivin levels were successfully quantified in all pleural fluid samples, and they were significantly higher in samples obtained after thoracoscopic talc poudrage compared with baseline (P < .001). Patients with higher pleural fluid survivin levels at baseline had a significantly poorer pleurodesis outcome (P = .004). A 30 pg/mL cut-off for baseline survivin in pleural fluid predicted failure of pleurodesis with a 54% sensitivity and 79% specificity (P = .009). Moreover, median postpleurodesis survival of patients with baseline survivin levels ≥30 pg/mL was 4 months (range: 0.1-38), compared with 13 months (range: 0.1-259) in patients below that cut-off (P < .001).

CONCLUSION

Elevated pleural fluid survivin concentrations are useful to predict failure of pleurodesis and are associated with shorter survival in patients with malignant pleural effusion.

Anti-tumor Effect of Rhaponticum uniflorum Ethyl Acetate Extract by Regulation of Peroxiredoxin1 and Epithelial-to-Mesenchymal Transition in Oral Cancer

Objective: To explore whether Rhaponticum uniflorum (R. uniflorum) had anti-tumor effects in oral cancer and investigate the molecular mechanisms involved in these anti-tumor effects.

Methods: Chemical compositions of R. uniflorum ethyl acetate (RUEA) extracts were detected by ultra-performance liquid chromatography-Q/time-of-flight mass spectrometry (UPLC-Q/TOF-MS), followed by pharmacology-based network prediction analysis. The effects of RUEA extracts on proliferation, apoptosis, migration, and invasion ability of human oral squamous cell carcinoma (OSCC) cell line SCC15 were evaluated by CCK8 assay, Annexin V- fluorescein isothiocyanate/propidium iodide staining, wound healing assay, and Matrigel invasion assay, respectively. The mRNA and protein expression of peroxiredoxin1 (Prx1), the epithelial-to-mesenchymal transition (EMT) marker E-cadherin, vimentin, and Snail were determined by quantitative real-time reverse transcription polymerase chain reaction and western blotting. A mouse xenograft model of SCC15 cells was established to further evaluate the effect of RUEA extracts in vivo. Immunohistochemical assessment of Ki67 and terminal deoxynucleotidyl transferase dUTP nick end labeling staining of apoptotic cells were performed on the tumor tissues to assess the effects of RUEA extracts on proliferation and apoptosis.

Results: Fourteen compounds were identified from RUEA extracts by UPLC-Q/TOF-MS. The pharmacology-based network prediction analysis showed that Prx1 could be a potential binder of RUEA extracts. In SCC15 cells, RUEA extracts inhibited cell viability, induced apoptosis, and suppressed cell invasion and migration in a concentration-dependent manner. After treatment with RUEA extracts, the mRNA and protein expression of E-cadherin increased, whereas those of Prx1, vimentin, and Snail decreased. RUEA extracts also affected the EMT program and suppressed cell invasion and migration in Prx1 knockdown SCC15 cells. In an OSCC mouse xenograft model, RUEA extracts (25 and 250 mg/kg) significantly inhibited the growth of tumors. Compared with the control group, Ki67 expression was reduced and apoptosis rates were elevated in the transplanted tumors treated with RUEA extracts. RUEA extracts increased the expression of E-cadherin and decreased the expression of Prx1, vimentin, and Snail in vivo.

Conclusion: RUEA extracts inhibited tumor growth and invasion by reducing Prx1 expression and suppressing the EMT process in OSCC. RUEA extracts may be a potential candidate for OSCC treatment.

Analysis of sentinel node biopsy combined with other diagnostic tools in staging cN0 head and neck cancer: A diagnostic meta-analysis

BACKGROUND

The purpose of this was to find a staging strategy sensitive enough to reduce the risk of occult metastases in cN0 head and neck cancer to below 15% to 20%.

METHODS

A total of 73 articles were selected for analysis of the diagnostic performance in staging cN0 head and neck cancer. Hypothetical estimation of negative predictive value (NPV) was calculated based on the Bayesian theory.

RESULTS

The pooled estimates for sensitivity were 56.4% and 84.9% for ultrasound-guided fine-needle aspiration (FNA) and sentinel node biopsy (SNB). The pooled estimates for sensitivity were 47.0%, 56.6%, 48.3%, and 63.3% for CT, MRI, positron emission tomography (PET), and ultrasound, respectively. The pooled estimates for specificity were 88.9%, 82.5%, 86.2%, and 79.1% for CT, MRI, PET, and ultrasound. In estimation, the CT or MRI with SNB strategies had NPV higher than 85% even when the pretest metastatic rate was 60%.

CONCLUSION

The SNB procedure has the best performance. A combination of CT/MRI and SNB for cN0 head and neck cancer is preferred.

Aberrant Myosin 1b Expression Promotes Cell Migration and Lymph Node Metastasis of HNSCC

Lymph node metastasis is the major clinicopathologic feature associated with poor prognosis in patients with head and neck squamous cell carcinoma (HNSCC). Here, web-based bioinformatics meta-analysis was performed to elucidate the molecular mechanism of lymph node metastasis of human HNSCC. Preferential upregulation of Myosin 1b (MYO1B) transcript in HNSCC datasets was identified. Myo1b mRNA was highly expressed in human HNSCC cells and patient tissue specimens compared with their normal counterparts as shown by quantitative PCR (qPCR) analyses. Immunohistochemistry (IHC)-detected Myo1b expression was significantly correlated with lymph node metastases in patients with oral cancer of the tongue. HNSCC with high expression of Myo1b and chemokine receptor 4 (CCR4), another metastasis-associated molecule, was strongly associated with lymph node metastasis. RNA interference (RNAi) of Myo1b in HNSCC cells, SAS and HSC4, significantly inhibited migratory and invasive abilities through decreased large protrusion formation of cell membranes. Finally, Myo1b knockdown in SAS cells significantly inhibited in vivo cervical lymph node metastases in a cervical lymph node metastatic mouse model system.

IMPLICATIONS

Myo1b is functionally involved in lymph node metastasis of human HNSCC through enhanced cancer cell motility and is an attractive target for new diagnostic and therapeutic strategies for patients with HNSCC.

The effect of epiregulin on epidermal growth factor receptor expression and proliferation of oral squamous cell carcinoma cell lines

Background

Epiregulin (EPR) is a novel member of the epidermal growth factor (EGF) family. It has been shown to promote wound healing in oral epithelium, enhance proliferation of other epithelial tissues, and is involved in several epithelial-related malignancies such as colorectal, lung, and bladder carcinoma. More recently, EPR transcripts were found to be high in a study on archival oral squamous cell carcinoma (OSCC) specimens. This implies that EPR may be responsible for the progression of OSCC. The aim of this was to elucidate the effects of EPR on (i) cell morphological changes, (ii) cell proliferation and (iii) receptor expression of the H-series OSCC cell lines.

Methods

The clinicopathological origin and the expression of the epidermal growth factor receptor (EGFR) and ErbB4 receptors of the H-series cell lines were initially characterised. Based on these parameters, two of the H-series cell lines, namely H103 and H357 were selected for downstream experiments. The cell lines were treated with 1 ng/ml, 10 ng/ml, and 20 ng/ml of EPR for 24 and 48 hours in all subsequent experiments. Untreated cells acted as the control which was used for comparison with each treated group. The cell morphological changes, cell proliferation and receptor expression of the OSCC cell lines were evaluated using phase contrast microscopy, 5-bromo-2’-deoxy-uridine (BrdU) assays and flow cytometry respectively. The results were compared and analysed using the student t-test.

Results

There were no appreciable morphological changes in the cells regardless of the dose of EPR tested nor between the different timelines. There were no significant changes in cell proliferation after EPR treatment. As for the effect of EPR on receptor expression, 20 ng/ml of EPR significantly reduced the density of EGFR expression (p value = 0.049) in the H103 cell line after the 24-hour treatment. No other statistically significant changes were detected.

Conclusions

The results show that EPR had no effect on the morphology and proliferativity of OSCC cells. However, the significant decline in EGFR expression after EPR treatment suggests that EPR might play an important role in the regulation of EGFR expression and hence OSCC progression.

Immunoreactivity of the 14F7 Mab Raised against N-Glycolyl GM3 Ganglioside in Primary Lymphoid Tumors and Lymph Node Metastasis

The reactivity of the 14F7 Mab, a highly specific IgG1 against N-glycolyl GM3 ganglioside (NeuGcGM3) in normal tissues, lymphomas, lymph node metastasis, and other metastatic sites was assessed by immunohistochemistry. In addition, the effect of chemical fixation on the 14F7 Mab staining using monolayers of P3X63Ag.653 cells was also evaluated. Moreover, the ability of 14F7 to bind NeuGcGM3 ganglioside inducing complement-independent cytotoxicity by a flow cytometry-based assay was measured. The 14F7 Mab was reactive in unfixed, 4% paraformaldehyde, 4% formaldehyde, and acetone fixed cells. Postfixation with acetone did not alter the localization of NeuGcGM3, while the staining with 14F7 Mab was significantly eliminated in both cells fixed and postfixed with methanol but only partially reduced with ethanol. The staining with 14F7 Mab was evidenced in the 89.2%, 89.4%, and 88.9% of lymphomas, lymph node metastasis, and other metastatic sites, respectively, but not in normal tissues. The treatment with 14F7 Mab affected both morphology and membrane integrity of P3X63Ag.653 cells. This cytotoxic activity was dose-dependent and ranged from 24.0 to 84.7% (10-1000  μ g/mL) as compared to the negative control. Our data could support the possible use of NeuGcGM3 as target for both active and passive immunotherapy against malignancies expressing this molecule.

Autocrine and paracrine loops between cancer cells and macrophages promote lymph node metastasis via CCR4/CCL22 in head and neck squamous cell carcinoma

Lymph node metastasis is a poor prognostic factor for patients with head and neck squamous cell carcinoma (HNSCC). However, its molecular mechanism has not yet been fully understood. In our study, we investigated the expression of CCR4 and its ligand CCL22 in the HNSCC tumor microenvironment and found that the CCR4/CCL22 axis was involved in lymph node metastasis of HNSCC. CCR4 was expressed in 20 of 31 (64.5%) human tongue cancer tissues, and its expression was significantly correlated with lymph node metastasis (p < 0.01) and lymphatic invasion (p < 0.05). CCR4 was expressed in three of five human HNSCC cell lines tested. CCR4(+) HNSCC cells, but not CCR4(-) cells, showed enhanced migration toward CCL22, indicating that functional CCR4 was expressed in HNSCC cell lines. CCL22 was also expressed in cancer cells (48.4% of tongue cancer tissues) or CD206(+) M2-like macrophages infiltrated in tumors and draining lymph nodes. CCL22 produced by cancer cells or CD206(high) M2-like macrophages increased the cell motility of CCR4(+) HNSCC cells in vitro in an autocrine or paracrine manner. In the mouse SCCVII in vivo model, CCR4(+) cancer cells, but not CCR4(-) cells, metastasized to lymph nodes which contained CCL22 producing M2-like macrophages. These results demonstrate that lymph node metastasis of CCR4(+) HNSCC is promoted by CCL22 in an autocrine or M2-like macrophage-dependent paracrine manner. Therefore, the CCR4/CCL22 axis may be an attractive target for the development of diagnostic and therapeutic strategies for patients with HNSCC.

Dysregulation of microRNA-34a expression in head and neck squamous cell carcinoma promotes tumor growth and tumor angiogenesis

BACKGROUND

MicroRNAs (miRs) are small non-coding RNAs that play an important role in cancer development where they can act as oncogenes or as tumor-suppressors. miR-34a is a tumor-suppressor that is frequently downregulated in a number of tumor types. However, little is known about the role of miR-34a in head and neck squamous cell carcinoma (HNSCC).

METHODS AND RESULTS

miR-34a expression in tumor samples, HNSCC cell lines and endothelial cells was examined by real time PCR. Lipofectamine-2000 was used to transfect miR-34a in HNSCC cell lines and human endothelial cells. Cell-proliferation, migration and clonogenic survival was examined by MTT, Xcelligence system, scratch assay and colony formation assay. miR-34a effect on tumor growth and tumor angiogenesis was examined by in vivo SCID mouse xenograft model. Our results demonstrate that miR-34a is significantly downregulated in HNSCC tumors and cell lines. Ectopic expression of miR-34a in HNSCC cell lines significantly inhibited tumor cell proliferation, colony formation and migration. miR-34a overexpression also markedly downregulated E2F3 and survivin levels. Rescue experiments using microRNA resistant E2F3 isoforms suggest that miR-34a-mediated inhibition of cell proliferation and colony formation is predominantly mediated by E2F3a isoform. In addition, tumor samples from HNSCC patients showed an inverse relationship between miR-34a and survivin as well as miR-34a and E2F3 levels. Overexpression of E2F3a completely rescued survivin expression in miR-34a expressing cells, thereby suggesting that miR-34a may be regulating survivin expression via E2F3a. Ectopic expression of miR-34a also significantly inhibited tumor growth and tumor angiogenesis in a SCID mouse xenograft model. Interestingly, miR-34a inhibited tumor angiogenesis by blocking VEGF production by tumor cells as well as directly inhibiting endothelial cell functions.

CONCLUSIONS

Taken together, these findings suggest that dysregulation of miR-34a expression is common in HNSCC and modulation of miR34a activity might represent a novel therapeutic strategy for the treatment of HNSCC.

Current Concepts of Metastasis Formation

The development of secondary distant organ and lymph node metastasis has an extraordinary impact on the prognosis of patients with solid cancer. In most cases the advent of metastatic growth represents the turning point from a local, potentially curable, disease to a systemic non-curable situation. As a highly regulated process, metastasis formation follows a distinct, non-random pattern characteristic for each tumor entity. Metastasis formation and strategies to prevent this lethal event in the progression of cancer is of fundamental interest for cancer science and patient care. In this special issue of Cancers, papers highlighting cellular mechanisms of metastasis formation, genetic and epigenetic aspects associated with organ and tumor specific metastasis formation, as well as papers outlining experimental and clinical therapeutic concepts for anti-metastatic treatment are included. [...].