Matrix metalloproteinase 9 inhibits the motility of highly aggressive HSC-3 oral squamous cell carcinoma cells.

Pro-tumorigenic activities of matrix metalloproteinase (MMP) 9 have been linked to many cancers, but recently the tumour-suppressing role of MMP9 has also been elucidated. The multifaceted evidence on this subject prompted us to examine the role of MMP9 in the behaviour of oral tongue squamous cell carcinoma (OTSCC) cells. We used gelatinase-specific inhibitor, CTT2, and short hairpin (sh) RNA gene silencing to study the effects of MMP9 on proliferation, motility and invasion of an aggressive OTSCC cell line, HSC-3. We found that the migration and invasion of HSC-3 cells were increased by CTT2 and shRNA silencing of MMP9. Proliferation, in turn, was decreased by MMP9 inhibition. Furthermore, arresten-overexpressing HSC-3 cells expressed increased levels of MMP9, but exhibited decreased motility compared with controls. Interestingly, these cells restored their migratory capabilities by CTT2 inhibition of MMP9. Hence, although higher MMP9 expression could give rise to an increased tumour growth in vivo due to increased proliferation, in some circumstances, it may participate in yet unidentified molecular mechanisms that reduce the cell movement in OTSCC.

Oral squamous cell carcinoma: Effect of tobacco and alcohol on cancer location.

INTRODUCTION: The underlying factors of oral squamous cell cancers (OSCC) have been elucidated, but studies have focused little on etiological differences in affected oral cavity sites. The aim of this retrospective study was to clarify the role of carcinogen exposure in OSCC of different oral cavity areas. METHODS: A cross-sectional study of patients with primary OSCC was conducted retrospectively, based on patient records from Helsinki University Hospital, Finland, between January 2016 and December 2020. The patients' self-reported history of tobacco smoking and alcohol use was explained by tumor site, age, sex, tumor size, and lymph node status in a logistic regression model. The information on smoking and alcohol use was compiled from a patient background form. RESULTS: In 519 patients, tumors occurred most often in the tongue (51%), gingiva (21%), or floor of the mouth (FOM; 15%). FOM had 26-fold greater odds for a history of smoking and alcohol use than other tumor sites (OR=25.78; 95% CI: 8.02-82.95; p<0.001). Gingival and buccal sites were associated significantly less with smoking and alcohol use (OR=0.43, 95% CI: 0.28-0.67; p<0.001 and OR=0.47; 95% CI: 0.25-0.92; p<0.026, respectively). Patients of older age were less likely to have a history of smoking and alcohol use (AOR=0.95; 95% CI: 0.94-0.97; p<0.001) than younger patients. Tumor size (T3-4) and FOM increased the odds for history of smoking and alcohol use (AOR=1.73; 95% CI: 1.15-2.60; p=0.009 and AOR=26.15; 95% CI: 8.01-84.84; p<0.001, respectively). CONCLUSIONS: OSCC of oral cavity sites has notable differences in etiology. FOM seems to be related almost exclusively to conventional smoking and heavy alcohol use.

Fluctuating roles of matrix metalloproteinase-9 in oral squamous cell carcinoma.

One hallmark of cancer is the degradation of the extracellular matrix (ECM), which is caused by proteinases. In oral cancers, matrix metalloproteinases (MMPs), especially MMP-9, are associated with this degradation. MMPs break down the ECM allowing cancer to spread; they also release various factors from their cryptic sites, including cytokines. These factors modulate cell behavior and enhance cancer progression by regulating angiogenesis, migration, proliferation, and invasion. The development of early metastases is typical for oral cancer, and increased MMP-9 expression is associated with a poor disease prognosis. However, many studies fail to relate MMP-9 expression with metastasis formation. Contrary to earlier models, recent studies show that MMP-9 plays a protective role in oral cancers. Therefore, the role of MMP-9 is complicated and may fluctuate throughout the different types and stages of oral cancers.

Differences in characteristics and infection severity between odontogenic and other bacterial oro-naso-pharyngeal infections.

BACKGROUND: Different bacterial infections of the oro-naso-pharyngeal (ONP) region may progress and require hospital care. The present study clarified differences in infection characteristics between hospitalized patients with odontogenic infections (OIs) and other bacterial ONP infections. The specific aim was to evaluate clinical infection variables and infection severity according to infection aetiology, particularly regarding features of OIs compared with other ONPs. METHODS: Records of patients aged ≥16 years requiring hospital care for an acute bacterial ONP infection in the emergency units of Otorhinolaryngology or Oral and Maxillofacial Surgery at the Helsinki University Hospital (Helsinki, Finland) during 2019 were evaluated retrospectively. The main outcome variables were need for intensive care unit (ICU) treatment and length of hospital stay. The primary predictor variable was infection category, defined as OI or other ONP. The secondary predictor variable was specific ONP infection group. Additional predictor variables were primary clinical infection signs, infection parameters at hospital admission, and delay from beginning of symptoms to hospitalization. Explanatory variables were sex, age, current smoking, heavy alcohol use or substance abuse, and immunosuppressive disease, immunosuppressive medication, or both. Comparison of study groups was performed using Fisher's exact test, student's t-test, and Mann-Whitney U. RESULTS: A total of 415 patients with bacterial ONPs fulfilled the inclusion criteria. The most common infections were oropharyngeal (including peritonsillar, tonsillar, and parapharyngeal infections; 51%) followed by infections from the odontogenic origin (24%). Clinical features of OIs differed from other ONPs. Restricted mouth opening, skin redness, or facial or neck swelling (or both) were found significantly more often in OIs (p < 0.001). OIs required ICU care significantly more often than other ONPs (p < 0.001) and their hospital stay was longer (p = 0.017). CONCLUSIONS: Infections originating from the tonsillary and dental origin had the greatest need for hospitalization. Clinical features of OIs differed; the need for ICU treatment was more common and hospital stay was longer compared with other ONPs. Preventive care should be emphasized regarding OIs, and typical infection characteristics of ONP infection subgroups should be highlighted to achieve early and prompt diagnosis and treatment and to reduce hospitalization time.

Trypsin-2 enhances carcinoma invasion by processing tight junctions and activating ProMT1-MMP.

Enhanced proteolysis and altered tight junction (TJ) proteins associate with carcinoma invasion. We hypothesized that trypsin-2, a tumor-associated serine proteinase, induces tongue carcinoma invasion by activating pro-membrane type-1 matrix metalloproteinase (MT1-MMP) and disturbing the TJs. The effects of invasion were analyzed using trypsin-2 over-expressing human tongue squamous cell carcinoma cells (Try2-HSC-3) in vitro and in vivo. The invasion of Try2-HSC-3 cells was increased in mouse xenografts and human organotypic model. Trypsin-2 activated proMT1-MMP, as well as altered the expression of TJ protein claudin-7. In conclusion, trypsin-2 over-expression enhanced tongue carcinoma cell invasion by various genetic and proteolytic mechanisms.

Role of RNA binding protein HuR in ductal carcinoma in situ of the breast.

HuR is a ubiquitously expressed RNA-binding protein that modulates gene expression at the post-transcriptional level. It is predominantly nuclear, but can shuttle between the nucleus and the cytoplasm. While in the cytoplasm HuR can stabilize its target transcripts, many of which encode proteins involved in carcinogenesis. While cytoplasmic HuR expression is a marker of reduced survival in breast cancer, its role in precursor lesions of malignant diseases is unclear. To address this we explored HuR expression in atypical ductal hyperplasia (ADH) and in ductal in situ carcinomas (DCIS). We show that cytoplasmic HuR expression is elevated in both ADH and DCIS when compared to normal controls, and that this expression associated with high grade, progesterone receptor negativity and microinvasion and/or tumour-positive sentinel nodes of the DCIS. To study the mechanisms of HuR in breast carcinogenesis, HuR expression was silenced in an immortalized breast epithelial cell line (184B5Me), which led to reduction in anchorage-independent growth, increased programmed cell death and inhibition of invasion. In addition, we identified two novel target transcripts (CTGF and RAB31) that are regulated by HuR and that bind HuR protein in this cell line. Our results show that HuR is aberrantly expressed at early stages of breast carcinogenesis and that its inhibition can lead to suppression of this process. ArrayExpress Accession No. E-MEXP-3035.

Cathepsin K is present in invasive oral tongue squamous cell carcinoma in vivo and in vitro.

OBJECTIVES: Cathepsin K, a lysosomal cysteine protease, is expressed in the tumor microenvironment (TME) of skin carcinoma, but nothing is known about cathepsin K in oral tongue squamous cell carcinoma (OTSCC). Our aim was to describe the expression of cathepsin K in invasive OTSCC in vitro and in a series of clinical cancer specimens. MATERIALS AND METHODS: OTSCC invasion in vitro was studied using invasive HSC-3 tongue carcinoma cells in 3D organotypic models. In total, 121 mobile tongue OTSCCs and 10 lymph node metastases were analyzed for cathepsin K expression. The association between cathepsin K expression and clinicopathological factors was evaluated. RESULTS: Cysteine protease inhibitor E64 and cathepsin K silencing significantly (p<0.0001) reduced HSC-3 cell invasion in the 3D models. Cathepsin K was expressed in a majority of carcinoma and metastatic cells, but the expression pattern in carcinoma cells did not correlate with clinical parameters. Instead, the weak expression of cathepsin K in the invasive TME front correlated with increased overall recurrence (p<0.05), and in early-stage tumors this pattern predicted both cancer recurrence and cancer-specific mortality (p<0.05 and p<0.005, respectively). CONCLUSIONS: Cathepsin K is expressed in OTSCC tissue in both carcinoma and TME cells. Although the diminished activity and expression in aggressive tongue HSC-3 cells reduced 3D invasion in vitro, the amount of cathepsin K in carcinoma cells was not associated with the outcome of cancer patients. Instead, cathepsin K in the invasive TME front seems to have a protective role in the complex progression of tongue cancer.

Selective gelatinase inhibitor peptide is effective in targeting tongue carcinoma cell tumors in vivo.

BACKGROUND: Matrix metalloproteinases (MMP) are strongly associated with cancer progession. Broad-spectrum MMP inhibition is rarely beneficial clinically due to adverse effects. Of all MMPs, the gelatinases are associated with the spread of several types of cancer, including oral carcinoma. We have developed gelatinase-specific peptides, as well as their fusion with green fluorescent protein (GFP), capable of effectively targeting carcinomas. MATERIALS AND METHODS: Effects on tumor growth and lymphatic micrometastatic spread in vivo was studied by use of HSC-3-cell xenografted athymic nude mice. Antigelatinolytic mono- vs. polytherapies, as well as biological activity of peptide-GFP fusion, were also analyzed in vivo. RESULTS: Antigelatinolytic therapy effectively inhibited growth of xenografted tumors in mice but the proportion of enlarged lymph nodes remained the same; antigelatinolytic polytherapy seemed not to potentiate the antitumor effects. The peptide-GFP chimera sustained its activity in vivo and effectively homed to the primary tumors. CONCLUSION: Peptide gelatinase inhibitors are effective in inhibiting primary tumor growth but alone do not prevent the spread of carcinoma cells; however, their bioactive GFP fusion is a candidate for tumor characterization and imaging.

Expression of claudins 1, 4, 5, and 7 and occludin, and relationship with prognosis in squamous cell carcinoma of the tongue.

Claudins and occludin are tight junctional proteins known to play a role in normal tissues and epithelial tumors. We analyzed the distribution patterns of claudins 1, 4, 5, and 7 and occludin in the superficial and invasive front of squamous cell carcinoma of the tongue of 97 patients and their relationship to cause-specific (squamous cell carcinoma of the tongue) patient survival (median follow-up period of 33.5 months; range, 1-234 months). Claudins 1 and 7 were strongly expressed, claudin 4 had moderate expression, whereas claudin 5 was least expressed. Occludin staining was mostly negative or very weak. Western blot analysis of tongue carcinoma (HSC-3) cells showed that all these proteins are also expressed in vitro. In cause-specific survival analysis, strong and low immunoreactivity of claudin 7 tended to be associated with decreased survival compared with medium immunoreactivity. We suggest that analyzing the immunohistologic staining levels of claudin 7 could be used for the prognostic purposes in patients with tongue squamous cell carcinoma.

Intracellular co-localization of trypsin-2 and matrix metalloprotease-9: possible proteolytic cascade of trypsin-2, MMP-9 and enterokinase in carcinoma.

Tumor-associated trypsin-2 and matrix metalloprotease-9 (MMP-9) are associated with cancer, particularly with invasive squamous cell carcinomas. They require activation for catalytical competence via proteolytic cascades. One cascade is formed by enterokinase, trypsin-2 and MMP-9; enterokinase activates trypsinogen-2 to trypsin-2, which is an efficient proMMP-9 activator. We describe here that oral squamous cell carcinomas express all members of this cascade: MMP-9, trypsin-2 and enterokinase. The expression of enterokinase in a carcinoma cell line not derived from the duodenum was shown here for the first time. Enterokinase directly cleaved proMMP-9 at the Lys65-Ser66 site, but failed to activate it in vitro. We demonstrated by confocal microscopy that MMP-9 and trypsin-2 co-localized in intracellular vesicles of the carcinoma cells. This co-localization of trypsin-2 and MMP-9 resulted in intracellular proMMP-9 processing that represented fully or partially activated MMP-9. However, although both proteases were present also in various bone tumor tissues, MMP-9 and trypsin-2 never co-localized at the cellular level in these tissues. This suggests that the intracellular vesicular co-localization, storage and possible activation of these proteases may be a unique feature for aggressive epithelial tumors, such as squamous cell carcinomas, but not for tumors of mesenchymal origin.