Distant metastasis from oral cancer: A review and molecular biologic aspects

Emerging insights into the biology of metastasis: A review article

Metastasis means the dissemination of the cancer cells from one organ to another which is not directly connected to the primary site. Metastasis has a crucial role in the prognosis of cancer patients. A few theories, different types of cell and several molecular pathways have been proposed to explain the mechanism of metastasis. In this work, the related articles in the limited period of time, 2000-mid -2018 were reviewed, through search in PubMed, Google Scholar and Scopus database. The articles published in the last two decades related to the biology of cancer metastasis were selected and the most important factors were discussed. Metastasis is critical factor to predict survival in patients with advanced cancer and prognosis determines the treatment plan. Many different cell types and various signaling pathways control the metastatic process. Metastasis is a multistep process. Many signaling pathways and molecules are involved in metastasis. Increasing knowledge about the mechanism of metastasis can help in finding the promising targets of cancer therapy.

Norcantharidin Suppresses YD-15 Cell Invasion Through Inhibition of FAK/Paxillin and F-Actin Reorganization

Norcantharidin (NCTD), a demethylated derivative of cantharidin, has been reported to exhibit activity against various types of cancers. However, the anti-invasive effects of NCTD and its molecular mechanism in human mucoepidermoid carcinoma (MEC) remain incompletely elucidated. Clonogenic, wound healing, invasion, zymography, western blotting and immunocytochemistry assays were performed in YD-15 cells to investigate the anti-invasive effect of NCTD and its molecular mechanism of action. The inhibitory effects of NCTD on invasiveness were compared with those of a novel focal adhesion kinase (FAK) kinase inhibitor, PF-562271. NCTD markedly suppressed the colony formation, migration, and invasion of YD-15 cells as well as the activities of MMP-2 and MMP-9. It disrupted F-actin reorganization through suppressing the FAK/Paxillin axis. Moreover, NCTD exhibited a powerful anti-invasive effect compared with that of PF-562271 in YD-15 cells. Collectively, these results suggest that NCTD has a potential anti-invasive activity against YD-15 cells. This study may clarify the impact of NCTD on migration and invasion of human MEC cells.

Hidden intra-mandibular carcinoma cuniculatum appearing in a patient with metastatic prostate cancer: a case report

Background

Whereas the incidence of cancers increases, overall survival of cancerous patients improves. Preventing the onset of second primary cancer is a new public health challenge and requires a special attention from organ specialists. We report a rare case of carcinoma cuniculatum in a context of metastatic prostate cancer. No case was previously described. Diagnosis delay of carcinoma cuniculatum is frequent and particularly in case of endophytic intra-osseous topography. The aim of this case report is to remind that persistent pain requires medical evaluation to rule out any possibility of second primary cancer.

Case presentation

A 78-year-old patient followed for a metastatic prostate cancer had been describing neuralgic dental pain in the lower posterior left quadrant for several months. Healing delay of tooth #37 (second left mandibular molar) extraction socket in the painful region led to an intra-alveolar incisional biopsy, which showed a tumor widely invading the mandibular body. Radiologic, histopathologic and clinical elements finally concluded to an intra-osseous carcinoma cuniculatum. Duration of total treatment (oral biopsy to hemimandibulectomy) and follow up were about five months and one year respectively. Patient died before reconstruction.

Conclusion

This case recalls that any persistent tooth pain affecting cancer patients requires a thorough review to exclude any secondary primary cancers or any metastasis of the oral cavity and more specifically in jawbones.

Expression of IL-17 with tumor budding as a prognostic marker in oral squamous cell carcinoma

We evaluated the relationship between IL-17 expression and tumor budding in the oral squamous cell carcinoma (OSCC) tumor invasion front (TIF). We also analyzed the correlation between OSCC prognosis and the co-expression of IL-17 and tumor budding. We obtained tumor tissues, tumor margins, and adjacent normal tissues from a total of 80 patients with OSCC. We measured IL-17 expression by ELISA and performed hematoxylin and eosin (H&E) and immunohistochemical staining to evaluate the presentation of tumor budding and IL-17 expression in the TIF. IL-17 expression was significantly increased in the tumor tissues and margins compared with that in the normal tissues, which was confirmed by immunohistochemical staining. There were correlations between IL-17-positive tumor budding and T classification, lymph node metastasis, distant metastasis, clinical stage, and recurrence. In a multivariate survival analysis, the IL-17-positive tumor budding, besides tumor budding alone, was highly correlated with prognosis. Our results demonstrate a positive relationship between IL-17 expression and tumor budding in the OSCC TIF. IL-17 combined with tumor budding can serve as a valuable predictor of prognosis for patients with OSCC.

Unusual Case of Obstructive Jaundice

Most malignant obstructive jaundice arises from primary periampullary tumors and rarely from metastatic cancer of the head and neck. A 60-year-old male was diagnosed with obstructive jaundice due to metastatic squamous cell carcinoma of the tonsil. Only 12 cases of small bowel metastasis from the head and neck have been reported. Most of them originate from laryngeal squamous cell carcinoma, and only one case reported tonsillar cancer metastasizing to the ileum. Our case is the first one, to the best of our knowledge, to illustrate tonsillar cancer with metastasis to the duodenum causing obstructive jaundice.

Neoplastic Pathogenesis Associated with Cigarette Carcinogens

Cigarette smoke is widely regarded as a carcinogenic agent; thus, the incidence of relative neoplasms correlates to cigarette smoking (CS) on a global level. While CS is most commonly associated with carcinomas of the upper and lower respiratory tracts, studies have also associated CS with the pathogenesis of a variety of non-respiratory related neoplasms. The tobacco smoke emitted from cigarettes contains carcinogenic substances that can be harmful to the normal physiology of the human body. This study will elaborate on the incidence and etiology of carcinomas, as well as discuss, in detail, the role of tobacco in the pathogenesis of oral, esophageal, lung, gastric, pancreatic, renal, and bladder carcinomas.

Tooth and Advanced Oral Submucous Fibrosis Obscuring Buccal Squamous Cell Carcinoma: A Case Report and Literature Review

Oral squamous cell carcinoma is a leading cause of mortality due to late diagnosis in India and most other developing countries. Buccal squamous cell carcinoma is almost always preceded by premalignant conditions that include leukoplakia, erythroplakia, oral lichen planus, and submucous fibrosis of the oral cavity. Hence, these patients warrant regular screening by oral health care professionals and proper monitoring for any dysplastic changes. Implementing social awareness about early signs and symptoms, as well as education on self-oral screening methods so as to avoid the risk of late presentation of oral squamous cell carcinoma, should be made mandatory for such individuals to prevent further complications.

Interferon γ suppresses dentin sialophosphoprotein in oral squamous cell carcinoma cells resulting in antitumor effects, via modulation of the endoplasmic reticulum response

The expression of proinflammatory cytokines in various malignant neoplasms is widely considered to represent the host immune response to tumor development. The role of interferon (IFN)γ in head and neck squamous cell carcinoma, and its association with endoplasmic reticulum (ER) stress pathways, remains a subject of ongoing investigation. Dentin sialophosphoprotein (DSPP), which is a member of the small integrin-binding N-linked glycoproteins family, has been implicated in malignant transformation and invasion of oral squamous cell carcinoma (OSCC). Recent studies have established matrix metalloproteinase (MMP)20 as the cognate MMP partner of DSPP. The present study examined the effects of IFNγ treatment on DSPP and MMP20 expression, ER stress, the unfolded protein response (UPR), and calcium (Ca) homeostasis regulatory mechanisms in OSCC cells. The OSC2 OSCC cell line was treated with IFNγ at specific time-points. At each time-point, the mRNA expression levels of DSPP and MMP20, and those of ER-stress-, UPR- and Ca homeostasis-associated proteins [78-kDa glucose-regulated protein (GRP78), sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA2b), inositol 1,4,5-trisphosphate receptor (IP3r), protein kinase R-like ER kinase (PERK) and inositol-requiring enzyme 1 (IRE1)], were assessed by reverse transcription-quantitative polymerase chain reaction. The protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), proliferating cell nuclear antigen (PCNA) and cytochrome c were analyzed by western blotting. Cell viability, apoptosis and migration were evaluated by MTT, Annexin V-fluorescein isothiocyanate flow cytometry and wound-healing assays, respectively. IFNγ treatment significantly downregulated the mRNA expression levels of the major ER stress regulator GRP78 and, to a lesser extent, the UPR-associated molecule IRE1; however, IFNγ had no significant effect on PERK. With regards to ER Ca homeostasis molecules, treatment with IFNγ downregulated the mRNA expression levels of SERCA2b and upregulated those of IP3r. Furthermore, DSPP and MMP20 mRNA expression levels were significantly reduced following IFNγ treatment. Notably, treatment with IFNγ hampered OSC2 migration, reduced cell viability and PCNA protein expression, enhanced apoptosis, downregulated Bcl-2, and upregulated Bax and cytochrome c. Overall, IFNγ inhibited OSCC cell viability and migration, and increased apoptosis, possibly by regulating ER stress and UPR mechanisms. In addition, IFNγ-induced DSPP and MMP20 downregulation may correspond with alteration in ER Ca homeostasis.

Differences between epithelial and mesenchymal human tongue cancer cell lines in experimental metastasis

Distant metastasis represents the outcome with the worst prognosis for various types of malignant tumors, but little is known regarding the impact of interacting epithelial and mesenchymal phenotypic cancer cells within its etiopathogenesis. In a novel animal model, 48 male athymic Balb/c nude mice underwent subcutaneous and intravenous injection of human tongue cancer cell lines of green fluorescent mesenchymal and red fluorescent epithelial phenotypes, in order to visualize and monitor eventual phenotypic interaction in lung metastasis as well as experimental metastasis in in vivo, ex vivo and histopathological analyses. While the epithelial, but not the mesenchymal, phenotypic human tongue cancer cell line led to direct metastasis in the lungs when injected intravenously, neither of them, even when injected in combination, were able to establish distant metastasis. The results of the present study provide evidence regarding the role of epithelial phenotypic cancer cells in the release of experimental metastasis following tail vein injection in male athymic Balb/c nude mice, in addition to proving fluorescent human tongue cancer cells may be reliably detected under a fluorescence microscope even 8 weeks after the two injection types.

The Expression and Functional Significance of Vascular Endothelial-Cadherin, CD44, and Vimentin in Oral Squamous Cell Carcinoma

Objectives

Ninety percent of head and neck cancers are squamous cell carcinoma which develops in the oral cavity. Metastasis is the main causative factor for death in 90% of all cancer-related deaths and begins with the invasion of tumor cells through the walls of small blood vessels or lymph vessels. A growing body of evidence has shown that vasculogenic mimicry (VM) facilitates tumor growth and cancer metastasis. The current study aimed to present the role of vascular endothelial (VE)-cadherin, CD44, and vimentin in inducing VM and epithelial-mesenchymal transition (EMT) and to identify the cancer stem cell (CSC) niche in different grades of oral squamous cell carcinoma (OSCC).

Materials and Methods

A total of 63 OSCC samples (21 samples each grade) were collected from the archive of Pathology Department of Besat educational hospital, Hamadan, Iran, from 2000 to 2015. VE-cadherin, CD44, and vimentin/periodic acid-Schiff (PAS) double-staining were used to validate VM. VM was identified by the detection of PAS-positive loops surrounded by tumor cells. Chi-square test was used to examine the differences between the variables. Significant level was set at 0.05. Pearson's correlation was used to assess the co-localization of the markers.

Results

There were statistically significant differences between tumor grade and the expression levels of VE-cadherin, CD44, and vimentin (P = 0.000). In addition, significant differences were found between tumor grade and microvessel density (P = 0.000) and between tumor grade and VM (P = 0.000).

Conclusion

Our results may disclose a definite relationship between VE-cadherin, CD44 and vimentin expression levels, VM formation, EMT, CSCs, and microvessel count in OSCC samples. For this reason, it is suggested that VE-cadherin, CD44, and vimentin are related to angiogenesis and VM formation in OSCC, therefore, in tumor progression and metastasis. Recently, antitumor angiogenic therapies have been challenged. The presence of VM may explain the failure of antiangiogenic treatments.

LINC00511 interacts with miR-765 and modulates tongue squamous cell carcinoma progression by targeting LAMC2

BACKGROUND

Aimed at underlying the molecular regulatory mechanism and overall biological functions of LINC00511 in tongue squamous cell carcinoma (TSCC).

METHODS

The expression level of LINC00511 was examined by QRT-PCR. In particular, Tca-8113 cell line was selected for subsequent experiments, in which the expression level of LINC00511 was the most significant. Meanwhile, the effects of LINC00511 on cells proliferation, cell cycle distribution, and invasion of TSCC cells were explored using RNA knockdown tools with CCK-8, flow cytometry analysis, colony formation, and transwell assay. Further, bioinformatic analysis and the dual-luciferase reporter assay both were conducted to invalidate the ceRNAs regulatory mechanism of LINC00511 in TSCC.

RESULTS

LINC00511 was obviously upregulated in TSCC tissues and cell lines. Moreover, it was found that LINC00511 served as a competing endogenous RNA (ceRNA) through sponging miR-765 and ultimately modulated the derepression of laminin subunit gamma 2 (LAMC2). The inhibitory effects of miR-765 on TSCC cells proliferation, invasion as well as cell cycle distribution can be restored by the ectopic overexpression of LINC00511. Additionally, the restored capacity of LINC00511 promoted the expression of LAMC2, which was a downstream target of miR-765 and can be negatively regulated by miR-765.

CONCLUSIONS

A novel molecular axis of LINC00511/miR-765/LAMC2 was investigated to regulate the tumor development of TSCC. LINC00511 promoted the expression of LAMC2 via the ceRNA mechanism of sponging miR-765. The ceRNA regulatory network provided a novel understanding of TSCC pathogenesis and also shed light on exploiting the new field of lncRNA-directed therapy against TSCC.

A Rare Case of Colonic Metastases From Tonsillar Carcinoma: Case Report and Review of Literature

The incidence of tonsillar cancer has increased by four times in the United States over the last few decades likely due to recent increase in human papilloma virus (HPV) infections. The stage of the tumor predicts likelihood of metastasis, with advanced stages associated with higher chances of metastasis. The squamous cell carcinomas (SCCs) of the head and neck commonly metastasize to the lung, bone and liver in descending order. Tonsillar cancer rarely involves the small bowel and our review of the literature did not reveal any reported case of metastasis to the colon/large bowel. Our patient had locally metastatic tonsillar cancer, treated with partial pharyngectomy and selective neck dissection but later developed several bone and colonic metastases concurrently, likely secondary to hematogeneous dissemination after a few months of therapy. To the best of our knowledge, large bowel metastasis from head and neck SCC has never been reported in the literature. In these patients presenting with atypical gastrointestinal symptoms, a high index of suspicion should be maintained to determine the extent of metastasis and identify other metastatic sites.

Nanomedicine, an emerging therapeutic strategy for oral cancer therapy

Oral cavity and oropharyngeal carcinomas (oral cancer) represents a significant cause of morbidity and mortality. Despite efforts in improving early diagnosis and treatment, the 5-year survival rate of advanced stage of the disease is less than 63%. The field of nanomedicine has offered promising diagnostic and therapeutic advances in cancer. Indeed, several platforms have been clinically approved for cancer therapy, while other promising systems are undergoing exploration in clinical trials. With its ability to deliver drugs, nucleic acids, and MRI contrast agents with high efficiency, nanomedicine platforms offer the potential to improve drug efficacy and tolerability. The aim of the present mini-review is to summarize the current preclinical status of nanotechnology systems for oral cancer therapy. The nanoplatforms for delivery of chemopreventive agents presented herein resulted in significantly higher anti-tumor activity than free forms of the drug, even against a chemo-resistant cell line. Impressive results have also been obtained using nanoparticles to deliver chemotherapeutics, resulting in reduced toxicity both in vitro and in vivo. Nanoparticles have also led to improvements in efficacy of photodynamic therapies through the development of targeted magnetic nanoparticles. Finally, gene therapy using nanoparticles demonstrated promising results specifically with regards to inhibition of gene expression. Of the few in vivo studies that have been reported, many of these used animal models with several limitations, which will be discussed herein. Lastly, we will discuss several future perspectives in oral cancer nanoparticle-based therapy and the development of appropriate animal models, distinguishing between oral cavity and oropharyngeal carcinoma.

Metastasis to the Jawbones: A review of 453 cases

The purpose of the present article was to review the characteristics of the jawbone metastases to analyze all variables. A relevant English Literature search in PubMed, Scopus, and Google Scholar was performed. All variables such as age, gender, primary and secondary tumor sites were analyzed. There were 453 metastatic cases. The male-to-female ratio was 1.2:1, and the mean age of the patients was 53.4 years. The lung was the most common primary site in men, and breast in women. The most common metastatic site was the mandible, and adenocarcinoma was the most frequent histological diagnosis. Metastases to the jaw bones occur in the advanced stages of a malignancy hence; a careful examination of patients with jaw bone lesions is strongly suggested. Dentists, as well as general physicians, should take into consideration the possible presence of jaw metastases in cases which present atypical symptoms, especially in patients with known malignant disease.