Expression of protease-activated receptor-2 (PAR-2) in patients with nasopharyngeal carcinoma: correlation with clinicopathological features and prognosis

Angiogenesis in nasopharyngeal carcinoma: insights, imaging, and therapeutic strategies

Nasopharyngeal carcinoma (NPC) is a highly prevalent head and neck malignancy in southern China frequently diagnosed at advanced stages owing to subtle early symptoms and associated metastasis. Angiogenesis emerges as a pivotal factor in NPC progression, with numerous angiogenesis-related factors showing aberrant expression and contributing to increased neovascularization within NPC tumors. These abnormal vessels not only nourish tumor growth but also facilitate metastasis, culminating in unfavorable patient outcomes. Multiple studies have demonstrated the applicability of various imaging techniques for assessing angiogenesis in NPC tumors, thus serving as a foundation for personalized treatment strategies and prognostic assessments. Anti-angiogenic therapies have exhibited significant potential for inhibiting NPC angiogenesis and exerting anti-tumor effects. To enhance efficacy, anti-angiogenic drugs are frequently combined with other treatment modalities to synergistically enhance anti-tumor effects while mitigating the side effects associated with single-agent therapies, consequently improving patient prognosis. Identifying the potential mechanisms and key targets underlying NPC angiogenesis and exploring more effective detection and treatment approaches holds promise for shaping the future of NPC diagnosis, treatment, and prognosis, thereby offering new avenues and perspectives for research and clinical practice.

PAR1 and PAR4 exert opposite effects on tumor growth and metastasis of esophageal squamous cell carcinoma via STAT3 and NF-κB signaling pathways

BACKGROUND

Esophageal carcinogenesis is a multifactorial process in which genetic and environmental factors interact to activate intracellular signals, leading to the uncontrolled survival and growth of esophageal squamous cell carcinoma (ESCC) cells. The intracellular pathways of ESCC cells could be regulated by proteinase activated-receptors (PARs), which are comprised of four receptors (i.e., PAR-1, PAR-2, PAR-3, and PAR-4). Therefore, the function and possible mechanism of PAR1 and PAR4 in the progression of ECSS were explored in our study.

METHODS

First, we detected the expression levels of PAR1 and PAR4 in 27 cases of ESCC specimens and cell lines by RT-qPCR, IHC and western blot. Meanwhile, the correlation between PAR1/PAR4 expression levels, clinicopathological characteristics, and disease free survival was analyzed. Then, we constructed PAR1/PAR4 knockdown cell models and investigated the role of PAR1/PAR4 knockdown on the proliferation, apoptosis, changes of calcium flow, and metastasis of ESCC cells via MTT, flow cytometry, transwell and wound healing assays in vitro. Further, an experimental metastasis model in vivo was established to explore the role of stable PAR1/PAR4 knockdown on the growth and metastasis of ESCC cells. Finally, the role of nSMase2 in the activation of NF-κB induced by PAR4 and the role of NF-κB and STAT3 signaling pathways in the PAR1/PAR4-mediated tumor promoting or suppressive functions were measured by immunoprecipitation, western blot and immunofluorescence assays.

RESULTS

First, the integrated results demonstrated the expression levels of PAR1 and PAR4 are inversely proportional in ESCC. PAR1 potently enhanced tumor growth and metastasis, while PAR4 had an inhibitory effect. Further, the co-activation of STAT3 and NF-κB was involved in the PAR1 activation-induced tumor promoting effect, while only NF-κB participated in the PAR4 activation-induced tumor inhibitory effect in ESCC. To be specific, FAK/PI3K/AKT/STAT3/NF-κB signaling mediated PAR1 activation-induced tumor promoting effect and nSMase2/MAPK/NF-κB signaling mediated PAR4 activation-induced tumor inhibitory effect.

CONCLUSIONS

Overall, the study has provided new insights into the potential implication of PAR1 and PAR4 in the pathogenesis of ESCC. Besides, FAK/PI3K/AKT/STAT3/NF-κB and nSMase2/MAPK/NF-κB pathways may be novel targets for regulating tumor growth and metastasis in ESCC patients.

Effect of latent membrane protein 1 expression on overall survival in Epstein-Barr virus-associated cancers: a literature-based meta-analysis

Latent membrane protein 1 (LMP1) is identified as the main transforming oncoprotein of Epstein-Barr virus (EBV). LMP1 is frequently expressed in a variety of EBV-associated cancers, including nasopharyngeal carcinoma (NPC), non-Hodgkin lymphoma (NHL), Hodgkin disease (HD), and gastric cancer (GC). However, due to conflicting results, the prognostic value of LMP1 expression on clinical outcomes in EBV-associated cancers remains unclear. We performed a meta-analysis on 32 studies with a total of 3752 patients to explore the association between LMP1 expression and overall survival (OS) in EBV-associated cancers. Overall, LMP1 expression was significantly associated with poorer OS (hazard ratio, HR = 1.51, 95% confidence interval, CI, 1.13–2.03), irrespective of cancer type. Further analyses showed that LMP1 expression correlated with poorer OS in NPC (HR = 2.48, 95% CI, 1.77–3.47) and NHL patients (HR = 1.83, 95% CI, 1.07–3.15), but not in HD patients (HR = 0.98, 95% CI, 0.60–1.62) or GC patients (HR = 0.70, 95% CI, 0.44–1.12). Subgroup analyses indicated that the age and geographical factors seemed to have an effect on the clinical outcomes of HD patients with positive LMP1 expression. In conclusion, LMP1 expression can be used as a prognostic biomarker in NPC, NHL, and certain HD patients. This data suggests that novel therapies targeting LMP1 may improve clinical outcomes for EBV-associated cancer patients.

High density of tryptase-positive mast cells in human colorectal cancer: a poor prognostic factor related to protease-activated receptor 2 expression

Tryptase(+) mast cells (MCs), abundant in the invasive front of tumours, contribute to tissue remodelling. Indeed, protease-activated receptor-2 (PAR-2) activation by MC-tryptase is considered an oncogenic event in colorectal cancer (CRC). Recently, we have suggested NHERF1 as a potential new marker in CRC. In this study, we aimed to determine the distribution of tryptase(+) MCs and PAR-2 and to examine the relationship between PAR-2 and NHERF1, investigating their reputed usefulness as tumour markers. We studied a cohort of 115 CRC specimens including primary cancer (C) and adjacent normal mucosa (NM) by immunohistochemical double staining, analyzing the protein expression of MC-tryptase, PAR-2 and cytoplasmic NHERF1. MC density was higher in NM than in C. Tumours with high TNM stage and poor grade showed the highest MC density. A higher PAR-2 immunoreactivity characterized tumours most infiltrated by MCs compared with samples with low MC density. Furthermore, PAR-2 overexpression was associated with advanced TNM stage, poor grade and lymphovascular invasion (LVI). A positive correlation existed between tryptase(+) MC density and PAR-2 expression. Cytoplasmic NHERF1 was higher in C than in NM and overexpressing tumours resulted associated with nodal and distant metastases, poor grade and LVI. PAR-2 correlated with cytoplasmic NHERF1 and the PAR-2(+)/cytoplasmic NHERF1(+) expression immunophenotype identified tumours associated with unfavourable prognosis and aggressive clinical parameters. Our data indicate that the high density of tryptase(+) MCs at invasive margins of tumours was associated with advanced stages of CRC and was strongly correlated with PAR-2 expression.

Porphyromonas gingivalis promotes invasion of oral squamous cell carcinoma through induction of proMMP9 and its activation

Recent epidemiological studies have revealed a significant association between periodontitis and oral squamous cell carcinoma (OSCC). Furthermore, matrix metalloproteinase 9 (MMP9) is implicated in the invasion and metastasis of tumour cells. We examined the involvement of Porphyromonas gingivalis, a periodontal pathogen, in OSCC invasion through induced expression of proMMP and its activation. proMMP9 was continuously secreted from carcinoma SAS cells, while P. gingivalis infection increased proenzyme expression and subsequently processed it to active MMP9 in culture supernatant, which enhanced cellular invasion. In contrast, Fusobacterium nucleatum, another periodontal organism, failed to demonstrate such activities. The effects of P. gingivalis were observed with highly invasive cells, but not with the low invasivetype. P. gingivalis also stimulated proteinase-activated receptor 2 (PAR2) and enhanced proMMP9 expression, which promoted cellular invasion. P. gingivalis mutants deficient in gingipain proteases failed to activate MMP9. Infected SAS cells exhibited activation of ERK1/2, p38, and NF-kB, and their inhibitors diminished both proMMP9-overexpression and cellular invasion. Together, our results show that P. gingivalis activates the ERK1/2-Ets1, p38/HSP27, and PAR2/NF-kB pathways to induce proMMP9 expression, after which the proenzyme is activated by gingipains to promote cellular invasion of OSCC cell lines. These findings suggest a novel mechanism of progression and metastasis of OSCC associated with periodontitis.

Tumor-derived hepatocyte growth factor is associated with poor prognosis of patients with glioma and influences the chemosensitivity of glioma cell line to cisplatin in vitro

BACKGROUND

We examined the association of tumor-derived hepatocyte growth factor (HGF) with the clinicopathological features of gliomas and investigated the effect of HGF inhibition on the biological behavior of tumor cells in vitro in order to determine whether HGF is a valuable prognostic predictor for glioma patients.

METHODS

Seventy-six cases of glioma were collected. The tumor-derived HGF expression, cell proliferation index (PI) and intratumoral microvessels were evaluated by immunohistochemistry. Correlation between immunostaining and clinicopathological parameters, as well as the follow-up data of patients, was analyzed statistically. U87MG glioma cells were transfected with short interference (si)-RNA for HGF, and the cell viability, migratory ability and chemosensitivity to cisplatin were evaluated in vitro.

RESULTS

Both high HGF expression in tumor cells (59.2%, 45/76) and high PI were significantly associated with high-grade glioma and increased microvessels in tumors (P < 0.05). However, only histological grading (P = 0.004) and high-expression of HGF (P = 0.008) emerged as independent prognostic factors for the overall survival of glioma patients. The tumor-derived HGF mRNA and protein expressions were significantly decreased in vitro after transfection of HGF siRNA. HGF siRNA inhibited the cell growth and reduced cell migratory ability. Moreover, HGF siRNA transfection enhanced the chemosensitivity of U87MG glioma cells to cisplatin.

CONCLUSION

This study indicated that there was significant correlation among tumor cell-derived HGF, cell proliferation and microvessel proliferation in gliomas. HGF might influence tumor progression by modulating the cell growth, migration and chemoresistance to drugs. Increased expression of HGF may be a valuable predictor for prognostic evaluation of glioma patients.

Strong cross-talk between angiogenesis and EBV: do we need different treatment approaches in lymphoma cases with EBV and/or high angiogenic capacity

Angiogenesis is the new blood vessels formation and is the critical event for the growth of malignant diseases and plays a key role in the development, invasion, and metastasis of malignant tumors. Epstein-Barr virus (EBV) is an important carcinogen causing to the some neoplastic disorders and lytically infected cells may contribute to the growth of EBV-associated malignancies, and this phenomenon is related with enhancing angiogenesis. Due to the strong cross-talk between angiogenesis and viral carcinogenesis and increased information about the angiogenesis and viral carcinogenesis in lymphomas, we need new therapeutic approaches to cases with lymphoma. Due to the strong cross-talk between angiogenesis and viral lymphomagenesis, this association was reviewed in this study.

Macrophage migration inhibitory factor contributes angiogenesis by up-regulating IL-8 and correlates with poor prognosis of patients with primary nasopharyngeal carcinoma

BACKGROUND AND OBJECTIVES

We aim at the association of macrophage migration inhibitory factor (MIF) with neovascularization and survival of nasopharyngeal carcinoma (NPC), and determine whether MIF is a valuable prognostic predictor for NPC patients.

METHODS

One hundred and forty one cases of NPC and 25 normal tissues of nasopharynx were collected. The expression of MIF and interleukin 8 (IL-8) was evaluated in tissues microarray by immunostaining. Intratumoral microvessel density (IMD) in relation to immunostainings and clinicopathological factors were analyzed statistically as well as the follow-up data of patients.

RESULTS

High-expression of both MIF (69.5%) and IL-8 (56.0%) were significantly associated with increased microvessels and lymph node metastasis. High-expression of MIF, IL-8 and higher level of IMD were correlated with either patients' overall survival or disease-specific survival in univariate analysis, but only angiogenesis and lymph node status exhibited in relation to survival of patients as independent prognostic factor of NPC by multivariate analysis. In addition, high-expression of MIF and higher level of IMD were closely associated with locoregional failure of NPC patients.

CONCLUSIONS

MIF may contribute to lymph node metastasis in NPC by inducing angiogenesis through the way of upregulation of IL-8 expression in an autocrine EBV-independent pathway.

Prognostic Value of Protease-Activated Receptor 2 Expression in Oesophageal Squamous Cell Carcinoma

Protease-activated receptor-2 (PAR-2) is essential for the initiation and development of tumours, suggesting that the detection of PAR-2 expression might serve as a clinical marker in the prediction or diagnosis of clinical outcomes of malignant neoplasia. Using immunohisto chemical methods, this study investigated whether the detection of PAR-2 protein had clinical implications for patients with oesophageal squamous cell carcinoma (OSCC). PAR-2 protein was present at a high level in primary OSCC sites but at a low level in normal oesophageal tissue. The level of PAR-2 protein in tumours was significantly correlated with the clinical stage and histological grade of disease. Patients with tumours highly positive for PAR-2 protein had a significantly worse prognosis than those with lower PAR-2 levels. Thus, the over-expression of PAR-2 is a characteristic feature of OSCC and suggests that the immuno histochemical detection of raised levels of PAR-2 may be a potentially useful prognostic indicator.

Expression of protease activated receptor-2 in human colorectal cancer and its association with tumor progression

PURPOSE

Protease activated receptor-2 has been reported to promote the proliferation of colorectal cancer cells. The aim of this study was to investigate the relationship of protease activated receptor-2 expression to clinicopathologic factors to clarify its role in tumor progression and patient survival in human colorectal cancer.

METHODS

Immunohistochemical staining with anti-protease activated receptor-2 antibody was carried out and evaluated on samples from 295 patients with colorectal cancer obtained during surgical treatment at Kangnam St. Mary's Hospital, Seoul, Republic of Korea. Medical records were reviewed and relationships between immunostaining and clinicopathologic findings were evaluated.

RESULTS

Positive staining for protease activated receptor-2 was observed in samples from 100 patients (33.9%). Expression of protease activated receptor-2 was significantly associated with depth of tumor invasion (P = .013), liver metastasis (P = .008), TNM stage (P = .009), and tumor location (P = .011). However, protease activated receptor-2 expression did not significantly correlate with overall survival of patients and was not a significant negative prognostic factor for survival in univariate or multivariate analyses.

CONCLUSIONS

The expression of protease activated receptor-2 is related to tumor invasion and metastasis in human colorectal cancer. However, further studies are needed to clarify the role of protease activated receptor-2 in the prognosis of patients with colorectal cancer.

Increased expression of MMP9 is correlated with poor prognosis of nasopharyngeal carcinoma

INTRODUCTION

The aim of the present study was to analyze the expression of matrix metalloproteinase 9 (MMP9) in nasopharyngeal carcinoma (NPC) and its correlation with clinicopathologic features, including the survival of patients with NPC.

METHODS

Using real-time PCR, we detected the mRNA expression of MMP9 in normal nasopharyngeal tissues and nasopharyngeal carcinoma (NPC) tissues. Using immunohistochemistry analysis, we analyzed MMP9 protein expression in clinicopathologically characterized 164 NPC cases (116 male and 48 female) with age ranging from 17 to 80 years (median = 48.4 years) and 32 normal nasopharyngeal tissues. Cases with greater than or equal to 6 and less than 6 of the score value of cytoplasmic MMP9 immunostaining were regarded as high expression and low expression, respectively. The relationship between the expression levels of MMP9 and clinical features was analyzed.

RESULTS

The expression level of MMP9 mRNA was markedly greater in NPC tissues than that in the nasopharyngeal tissues. Immunohistochemical analysis revealed that the protein expression of MMP9 detected in NPC tissues was higher than that in the nasopharyngeal tissues (P = 0.004). In addition, high levels of MMP9 protein were positively correlated with the status of lymph node metastasis (N classification) (P = 0.002) and clinical stage (P < 0.001) of NPC patients. Patients with higher MMP9 expression had a significantly shorter overall survival time than did patients with low MMP9 expression. Multivariate analysis suggested that the level of MMP9 expression was an independent prognostic indicator (P = 0.008) for the survival of patients with NPC.

CONCLUSION

High level of MMP9 expression is a potential unfavorable prognostic factor for patients with NPC.

Protease-activated receptor-2 agonists promote cell invasion and metastasis in human esophageal cancer cell line EC109

AIM: To determine the expression of protease activated receptor-2 (PAR-2) in human esophageal cell line EC109, and to evaluate the effects of PAR-2 activation on cell invasion and migration.

METHODS: The expression of PAR-2 protein and mRNA in EC109 cells was determined by immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Methyl thiazol tetrazolium (MTT) assay, cell invasion and migration assay, semi-quantitative PCR and zymographic analysis were performed to examine whether endogenous PAR-2 activator trypsin and PAR-2 activating-peptide SLIGKV could alter cell proliferation, invasion, migration, and matrix metalloproteinase (MMP) production.

RESULTS: Both PAR-2 mRNA and protein were expressed in EC109 cells. PAR-2 mRNA was up-regulated in cells treated with trypsin or PAR-2-activating peptide SLIGKV (0.781 ± 0.045 and 0.653 ± 0.029 vs 0.491 ± 0.032, both P < 0.01), but not in those treated with control peptide VKGILS (P > 0.05). Trypsin and SLIGKV promoted the proliferation of EC109 cells in a dose- and time-dependent manner. No significant difference was noted in cell proliferation between untreated cells and cells treated with control peptide VKGILS. Treatment with trypsin or SLIGKV significantly increased the number of EC109 cells that passed through the Millicell inserts in the migration assay (72.5 ± 9.2 vs 31.6 ± 6.6, and 59.4 ± 8.7 vs 36.2 ± 9.8, both P < 0.01). Compared with untreated cells and cell treated with control peptide, trypsin and SLIGKV significantly increased the mRNA expression (0.719 ± 0.034 vs 0.341 ± 0.032, and 0.466 ± 0.042 vs 0.370 ± 0.021, both P < 0.01) and gelatinolytic activity (75.6 ± 6.1 vs 44.9 ± 4.2, and 60.4 ± 4.6 vs 39.3 ± 5.2, both P < 0.01) of MMP-9.

CONCLUSION: PAR-2 is expressed in EC109 cells. PAR-2 activation may be able to promote the invasion and metastasis of human esophageal carcimoma cells by stimulating MMP-9 production.