Oral carcinoma with perineural invasion has higher nerve growth factor expression and worse prognosis

A neural-related gene risk score for head and neck squamous cell carcinoma

OBJECTIVES

This study aimed to establish a neural-related gene risk score (NRGRS) for the prediction of head and neck squamous cell carcinoma prognosis and explore its predictive value on the benefit of immune checkpoint inhibitor therapy.

METHODS

Based on the transcriptome data of HNSCC patients (n = 546) from The Cancer Genome Atlas database, 37 neural-related hub genes were identified by weighted gene co-expression network analysis. Four genes (ITGA5, PYGM, GNG7 and ATP2A3) were identified to construct NRGRS using Lasso-Cox regression method based on the derivation cohort and validated in the Gene Expression Omnibus cohort (n = 109). The survival analysis was performed to validate the prognostic value of NRGRS and immune characteristics in NRGRS-defined subgroups were analyzed.

RESULTS

NRGRS-high patients had a worse overall survival than NRGRS-low patients. Tumors with high NRGRS were more likely to have high infiltration of naive CD4+ T cells, M0, M2 macrophages and resting mast cells, which illustrated suppressive immunity and less benefit from immunotherapy therapy.

CONCLUSION

NRGRS strongly correlates with survival and is a promising biomarker to predict immunotherapy benefits for head and neck cancer patients. This study provides evidence for the potential correlation between neural-related transcriptome alteration and immune activity.

Perineural Invasion Is a Significant Prognostic Factor in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

(1) Objectives: This systematic review and meta-analysis aimed to summarize current evidence regarding the prognostic role of perineural invasion (PNI) in patients with oral squamous cell carcinoma (OSCC). (2) Methods: We searched Cochrane Central, ProQuest, PubMed, Scopus, Science Direct, and Web of Science, using relevant keywords to identify eligible articles. Two independent reviewers conducted two-stage screening, data extraction, and quality assessment. The risk of bias was assessed using the Newcastle-Ottawa Scale (NOS) criteria. All analyses were performed using comprehensive meta-analysis (CMA; version 3.3.070) software. (3) Results: The study included 101 published articles encompassing 26,062 patients. The pooled analyses showed that PNI was associated with significantly worse overall survival (OS; HR = 1.45, 95% CI: 1.32-1.58; p < 0.001), worse disease-specific survival (DSS; HR = 1.87, 95% CI: 1.65-2.12; p < 0.001), and worse disease-free survival (DFS; HR = 1.87, 95% CI: 1.65-2.12; p < 0.001). Similarly, both local recurrence-free survival (LRFS) and regional recurrence-free survival (RRFS) were worse in patients with PNI (HR = 2.31, 95% CI: 1.72-3.10, p < 0.001; and HR = 2.04, 95% CI: 1.51-2.74, p < 0.001), respectively. The random-effect estimate of three studies demonstrated that the presence of PNI was associated with worse failure-free survival (FFS; HR = 2.59, 95% CI: 1.12-5.98, p < 0.001). (4) Conclusions: The current evidence suggests that PNI can be used as an independent predictor of the prognosis for patients with OSCC. The presence of PNI was associated with worse OS, DFS, DSS, FFS, and with recurrence. Asian patients and patients with extra-tumoral or peripheral PNI invasion were associated with worse prognosis.

Going Off Guidelines: An NCDB Analysis of Missed Adjuvant Therapy Among Surgically Treated Oral Cavity Cancer

OBJECTIVE

Patient factors associated with failure to receive adjuvant therapy after oral cavity cancer resection remain understudied. Here, we identified rates of missed adjuvant therapy, determined factors associated with missed therapy, and assessed associations with survival.

STUDY DESIGN

Retrospective cohort.

SETTING

National Cancer Database.

METHODS

Patients with resected oral cavity squamous cell carcinoma and known adjuvant therapy status were included. T3-4 stage, N2-3 stage, and lymphovascular invasion were considered indications for adjuvant radiation. Extranodal extension or positive margins were considered indications for chemoradiation. Patient factors were examined for associations with missed adjuvant therapy. Overall survival was evaluated by Cox proportional hazard analysis.

RESULTS

A total of 53,503 patients were included. 27.5% missed adjuvant therapy altogether, and 26.7% with a documented indication for chemoradiation missed chemotherapy. Factors associated with missed adjuvant therapy were age, white race, low income, metropolitan population, increasing comorbidities, travel distance, lip primary, and treatment at the academic facility. Factors associated with missed chemotherapy were age, female sex, nontongue subsite, and treatment at a nonacademic center. Among patients with indications for adjuvant radiation, missed radiation was associated with worse overall survival (hazard ratio [HR]: 1.42, 95% confidence interval [CI]: 1.31-1.53). Among patients with indications for adjuvant chemoradiation, missed chemotherapy was associated with worse overall survival (HR: 1.19, 95% CI: 1.09-1.29).

CONCLUSION

Missed adjuvant therapy occurs frequently after oral cavity resection. Patients treated at academic centers may be at risk of missed therapy related to travel distance, though these patients are more likely to receive adjuvant chemotherapy when indicated. Missed adjuvant therapy is associated with worse survival.

Midline involvement and perineural invasion predict contralateral neck metastasis that affects overall and disease-free survival in locally advanced oral tongue squamous cell carcinoma

Introduction

Although patients with oral squamous cell carcinoma who develop contralateral neck metastasis (CLNM) have worse survival outcomes than those without CLNM, accurate prediction of occult CLNM in clinically negative contralateral neck (contralateral cN0) remains difficult. This study aimed to identify clinicopathological factors that could reliably predict CLNM in patients with locally advanced (clinical T3 and T4a) tongue squamous cell carcinoma (TSCC).

Patients and methods

The medical data of 32 patients with cT3–4a TSCC who underwent curative surgery between 2010 and 2017 were retrospectively analyzed. The correlation of clinicopathological variables with CLNM was examined using logistic regression analysis. The diagnostic performance of significant variables was evaluated using the area under the receiver operating characteristic curves (AUC). Overall survival (OS) and disease-free survival (DFS) were assessed using a Cox proportional hazards model.

Results

CLNM was eventually confirmed in 11 patients (34.4%). Multivariate logistic regression showed that midline involvement [odds ratio (OR) = 23.10, P = 0.017] and perineural invasion (PNI, OR = 14.96, P = 0.014) were independent predictors of CLNM. Notably, the prediction model comprising a combination of midline involvement and PNI exhibited superior diagnostic performance with an even higher OR of 80.00 (P &lt; 0.001), accuracy of 90.3%, and AUC of 0.876. The multivariate Cox hazards model revealed independent significance of CLNM as an unfavorable prognostic factor for both OS [hazard ratio (HR) = 5.154, P = 0.031] and DFS (HR = 3.359, P = 0.038), as well as that of PNI for OS (HR = 5.623, P = 0.033).

Conclusion

Our findings suggest that coexisting midline involvement and PNI of the primary tumor is highly predictive of CLNM development, which independently affects both OS and DFS in patients with locally advanced TSCC. Such reliable prediction enables efficient control of CLNM by optimizing management of the contralateral cN0 neck, which will likely contribute to improved prognosis of those patients without unnecessarily compromising their quality of life.

Neurotrophin Pathway Receptors NGFR and TrkA Control Perineural Invasion, Metastasis, and Pain in Oral Cancer

Oral squamous cell carcinoma (OSCC) patients suffer from poor survival due to metastasis or locoregional recurrence, processes that are both facilitated by perineural invasion (PNI). OSCC has higher rates of PNI than other cancer subtypes, with PNI present in 80% of tumors. Despite the impact of PNI on oral cancer prognosis and pain, little is known about the genes that drive PNI, which in turn drive pain, invasion, and metastasis. In this study, clinical data, preclinical, and in vitro models are leveraged to elucidate the role of neurotrophins in OSCC metastasis, PNI, and pain. The expression data in OSCC patients with metastasis, PNI, or pain demonstrate dysregulation of neurotrophin genes. TrkA and nerve growth factor receptor (NGFR) are focused, two receptors that are activated by NGF, a neurotrophin expressed at high levels in OSCC. It is demonstrated that targeted knockdown of these two receptors inhibits proliferation and invasion in an in vitro and preclinical model of OSCC, and metastasis, PNI, and pain. It is further determined that TrkA knockdown alone inhibits thermal hyperalgesia, whereas NGFR knockdown alone inhibits mechanical allodynia. Collectively the results highlight the ability of OSCC to co-opt different components of the neurotrophin pathway in metastasis, PNI, and pain.

Molecular and Cellular Mechanisms of Perineural Invasion in Oral Squamous Cell Carcinoma: Potential Targets for Therapeutic Intervention

Simple Summary

Squamous cell carcinoma is the most common type of oral cavity cancer. It can spread along and invade nerves in a process called perineural invasion. Perineural invasion can increase the chances of tumor recurrence and reduce survival in patients with oral cancer. Understanding how oral cancer interacts with nerves to facilitate perineural invasion is an important area of research. Targeting key events that contribute to perineural invasion in oral cavity cancer may reduce tumor recurrence and improve survival. In this review, we describe the impact of perineural invasion in oral cancer and the mechanisms that contribute to perineural invasion. Highlighting the key events of perineural invasion is important for the identification and testing of novel therapies for oral cancer with perineural invasion.

Abstract

The most common oral cavity cancer is squamous cell carcinoma (SCC), of which perineural invasion (PNI) is a significant prognostic factor associated with decreased survival and an increased rate of locoregional recurrence. In the classical theory of PNI, cancer was believed to invade nerves directly through the path of least resistance in the perineural space; however, more recent evidence suggests that PNI requires reciprocal signaling interactions between tumor cells and nerve components, particularly Schwann cells. Specifically, head and neck SCC can express neurotrophins and neurotrophin receptors that may contribute to cancer migration towards nerves, PNI, and neuritogenesis towards cancer. Through reciprocal signaling, recent studies also suggest that Schwann cells may play an important role in promoting PNI by migrating toward cancer cells, intercalating, and dispersing cancer, and facilitating cancer migration toward nerves. The interactions of neurotrophins with their high affinity receptors is a new area of interest in the development of pharmaceutical therapies for many types of cancer. In this comprehensive review, we discuss diagnosis and treatment of oral cavity SCC, how PNI affects locoregional recurrence and survival, and the impact of adjuvant therapies on tumors with PNI. We also describe the molecular and cellular mechanisms associated with PNI, including the expression of neurotrophins and their receptors, and highlight potential targets for therapeutic intervention for PNI in oral SCC.

Asparagine Synthetase-Mediated l-Asparagine Metabolism Disorder Promotes the Perineural Invasion of Oral Squamous Cell Carcinoma

Dysregulated amino acids metabolism reciprocally interplays with evolutionary phenotypic characteristics of cancer cells to enhance metastasis. The high metastasis potential of oral squamous cell carcinoma (OSCC) can manifest with perineural invasion (PNI). We here aimed to determine the role of amino acids metabolism in OSCCs with different PNI statuses. Targeted metabolomics was used to quantify 48 amino acids in 20 fresh OSCC samples and 25 amino acids were successfully detected, within which 9 were significantly up-regulated in PNI positive (PNI+) samples. As its highest area under the curve value (0.9063), l-asparagine was selected as the biomarker to distinguish PNI+ from PNI negative (PNI-). Then, the key enzyme of l-asparagine, asparagine synthetase (ASNS), was investigated using immunohistochemistry with 86 OSCC patients. The results showed that ASNS mainly expressed in tumor epitheliums and positively correlated with lymph node metastasis and PNI. Moreover, subgroup survival analysis revealed that ASNS expression combined with PNI status significantly improved their prognostic value, which was confirmed by the TCGA OSCC cohort (n = 279). To validate whether ASNS promotes PNI, we determined ASNS expression levels in five OSCC cell lines and one normal oral keratinocyte, and HSC3 showed the lowest ASNS level but CAL33 had the highest. Therefore, HSC3 and CAL33 (or PBS as control) were selected and injected separately into sciatic nerves to construct the in vivo PNI mouse models. Although both models eventually developed the hind-limb paralysis, nerve dysfunction in the CAL33 model progressed significantly earlier than HSC3 (Day 9 vs. Day 24). Besides, CAL33 migrated significantly farther than HSC3 in the nerve microenvironment (P = 0.0003), indicating high ASNS expression is indispensable for OSCC progression, especially PNI formation, through l-asparagine metabolism alteration. This study provides novel insights into how amino acids metabolism disorders alter tumor neurotropism which helps cancer metastasis.

Perineural invasion, lactate dehydrogenase, globulin, and serum sodium predicting occult metastasis in oral cancer

OBJECTIVE

This study aimed to develop a nomogram to predict the neck occult metastasis in early (T1-T2 cN0) oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

The nomogram was developed in a training cohort of 336 early OSCC patients and was validated in a validation cohort including 88 patients. Independent predictors were calculated by univariate and multivariate logistic regression analyses.

RESULTS

In univariate logistical regression analysis, gender, perineural invasion (PNI), blood vessel invasion, mean corpuscular hemoglobin, aspartate aminotransferase, prealbumin, globulin (GLO), lactate dehydrogenase (LDH), serum sodium (NA), and serum chloride were significant associated with neck occult metastasis. Multivariate logistical regression analysis identified PNI (p < .001), LDH (p = .003), GLO (p = .019), and NA (p = .020) as independent predictors of neck occult metastasis. Cut-off values for LDH, GLO, and NA obtained from AUC were 142.5, 26.35, and 139.5, respectively. The nomogram based on PNI and categorical GLO, LDH, and NA exhibited a strong discrimination, with a C-indexes of 0.748 (95%CI = 0.688 to 0.810) in the training cohort and 0.751 (95%CI = 0.639 to 0.863) in the validation cohort.

CONCLUSIONS

A nomogram based on PNI, LDH, GLO, and NA for predicting the risk of neck lymph nodes occult metastasis in OSCC could help surgeons with therapy decision-making.

Perineural invasion in oral squamous cell carcinoma: Incidence, prognostic impact and molecular insight

BACKGROUND

The objective of this study was to characterise the incidence and prognostic correlation of perineural invasion (PNI) in oral squamous cell carcinoma and determine whether nerve growth factor and its receptor tyrosine Kinase A expression could be used as biological markers for PNI.

METHODS

A retrospective review of pathology reports of 430 patients with oral squamous cell carcinoma who were treated from 1992 to 2014 in Tayside, Scotland, was carried out. The expression of nerve growth factor and tyrosine kinase A was assessed with immunohistochemistry in 132 tissue sections of oral squamous cell carcinoma.

RESULTS

Perineural invasion was identified in 17.4% of oral squamous cell carcinomas. High expression of nerve growth factor and tyrosine kinase A was seen in 84% and 92% of oral squamous cell carcinoma, respectively. Tumours with PNI expressed nerve growth factor and tyrosine kinase A with a greater frequency than tumours without PNI. PNI and high expression of nerve growth factor were significantly associated with pain. PNI was significantly associated with stage IV tumours and poor disease-specific survival.

CONCLUSIONS

A higher level of expression of nerve growth factor and tyrosine kinase A may predict PNI and therefore may be considered as biological markers for PNI in oral squamous cell carcinoma. PNI and nerve growth factor overexpression may contribute to the pain generation in oral cancer patients. PNI and nerve growth factor expression can predict the aggressiveness and prognosis of oral squamous cell carcinoma patients.

Survival outcomes after surgical treatment of oral squamous cell carcinoma

OBJECTIVE

To identify the clinicopathological parameters that influence survival in patients with oral squamous cell carcinoma, in order to allow for the development of individualized surveillance programmes and reduce the delay in diagnosis of recurrence.

MATERIALS AND METHODS

Retrospective chart review of 553 patients with a treatment-naïve primary oral squamous cell carcinoma, who underwent primarily curative intended surgery. Exclusion criteria were neoadjuvant radio(chemo)therapy, follow-up < 1 year, perioperative death, inoperable disease, synchronous multiple malignancies and inadequate information on clinicopathological parameters.

RESULTS

The clinicopathological factors that influence overall survival, disease-free survival and locoregional control were calculated. In the multivariate survival analysis, the occurrence of recurrence, presence of extracapsular spread, T- and N-classification were shown to be independent risk factors for overall survival.

CONCLUSION

The identification of these risk factors can lead to the development of individualized follow-up programmes based on risk stratification. This allows for the earliest possible diagnosis of relapse which is essential to offer the patient a realistic second treatment chance and to improve survival rates.

Integrating Clinical and Genetic Analysis of Perineural Invasion in Head and Neck Squamous Cell Carcinoma

Introduction: Perineural invasion (PNI), a key pathological feature of head and neck squamous cell carcinoma (HNSCC), predicts poor survival. However, the associated clinical characteristics remain uncertain, and the molecular mechanisms are largely unknown. Materials and methods: HNSCC gene expression and corresponding clinical data were downloaded from The Cancer Genome Atlas (TCGA). Prognostic subgroup analysis was performed, and potential PNI risk factors were assessed with logistic regression. PNI-associated gene coexpression modules were identified with weighted gene coexpression network analysis (WGCNA), and key module gene functions and the roles of non-malignant cells in PNI were evaluated with a single-cell transcriptomic dataset (GSE103322). Results: PNI was significantly inversely associated with overall survival (HR, 2.08; 95% CI, 1.27 to 3.40; P = 0.004), especially in advanced patients (HR, 2.62; 95% CI, 1.48 to 4.64; P < 0.001). Age, gender, smoking history, and alcohol history were not risk factors. HPV-positive cases were less likely than HPV-negative cases to develop PNI (OR, 0.28; 95% CI, 0.09 to 0.76; P = 0.017). WGCNA identified a unique significantly PNI-associated coexpression module containing 357 genes, with 12 hub genes (TIMP2, MIR198, LAMA4, FAM198B, MIR4649, COL5A1, COL1A2, OLFML2B, MMP2, FBN1, ADAM12, and PDGFRB). Single-cell transcriptomic data analysis revealed that the genes in the PNI-associated module correlated with the signatures "EMT," "metastasis," and "invasion." Among non-malignant cells, fibroblasts had relatively high expression of the key genes. Conclusion: At the molecular and omic levels, we verified that PNI in HNSCC is a process of invasion rather than simple diffusion. Fibroblasts probably play an important role in PNI. Novelty & Impact Statements  The study is a thorough analysis of PNI in HNSCC from the clinical level to the molecular level and presents the first description of cancer-related PNI from the omics perspective to date as far as we know. We verified that PNI in HNSCC is a process of invasion rather than simple diffusion, at the molecular and omic levels. Fibroblasts were found to probably play an important role in PNI by analyzing single-cell transcriptomic data.

Perineural Invasion in Head and Neck Cancer

Perineural invasion (PNI) is a mechanism of tumor dissemination that can provide a challenge to tumor eradication and that is correlated with poor survival. Squamous cell carcinoma, the most common type of head and neck cancer, has a high prevalence of PNI. This review provides an overview of clinical studies on the outcomes and factors associated with PNI in head and neck cancer and on findings on cancer-nerve crosstalk.

Role of the nervous system in cancer metastasis

Cancer remains as one of the leading cause of death worldwide. The development of cancer involves an intricate process, wherein many identified and unidentified factors play a role. Although most studies have focused on the genetic abnormalities which initiate and promote cancer, there is overwhelming evidence that tumors interact within their environment by direct cell-to-cell contact and with signaling molecules, suggesting that cancer cells can influence their microenvironment and bidirectionally communicate with other systems. However, only in recent years the role of the nervous system has been recognized as a major contributor to cancer development and metastasis. The nervous system governs functional activities of many organs, and, as tumors are not independent organs within an organism, this system is integrally involved in tumor growth and progression.

Individual and co-expression patterns of nerve growth factor and heme oxygenase-1 predict shorter survival of gastric carcinoma patients

BACKGROUND

Nerve growth factor (NGF) is a neurotrophic factor which regulates cell development and proliferation. Recently, it has been suggested that NGF induces heme oxygenase-1 (HO1) expression, and that both NGF and HO1 are involved in the progression of malignant human tumors. However, exact roles of NGF and HO1 in tumorigenesis remain controversial. Therefore, we investigated the expression and correlation of NGF and HO1 in human gastric carcinoma tissues.

METHODS

We examined immunohistochemical expression of NGF and HO1 in 167 gastric carcinomas and compared with various prognostic clinicopathological factors.

RESULTS

The expression of NGF and HO1 was positive in 40% (67/167) and 51% (85/167) of cases, respectively, and their expression was significantly correlated with each other (p < 0.001). Individual expression patterns of NGF and HO1, and co-expression pattern of these two molecules were significantly associated with shorter survival by univariate analysis. HO1 expression (overall survival; p < 0.001, relapse-free survival; p = 0.002) and co-expression pattern of NGF and HO1 (overall survival; p = 0.002, relapse-free survival; p = 0.003) were independent poor prognostic indicators of gastric carcinoma patients by multivariate analysis.

CONCLUSIONS

These results demonstrate that the individual and co-expression patterns of NGF and HO1 might be used as prognostic indicators for gastric carcinoma patients.

Expression of NGF, GDNF and MMP-9 in prostate carcinoma

The aim of the present study was to investigate the immunohistochemical expression of NGF, GDNF and MMP-9 in benign prostatic hyperplasia (BPH), high grade prostatic intraepithelial neoplasia (HGPIN) and prostate cancer (PC), and to analyse their association with the clinicopathological parameters in PC cases. Immunohistochemistry was performed on the tissue microarray (TMA) sections of 30 BPH, 40 HGPIN and 121 primary PC tissues. There was a significant difference regarding the expression of NGF and GDNF between PC and HGPIN (p<0.0001; p<0.0001), and PC and BPH (p=0.001; p<0.0001), but not between HGPIN and BPH (p>0.05). Furthermore MMP-9 expression was significantly different among all groups (PC vs. HGPIN, p<0.0001; PC vs. BPH, p<0.0001; HGPIN vs. BPH, p=0.001). NGF, GDNF and MMP-9 expression was significantly stronger in cases with high Gleason score (p<0.0001, p=0.004, p<0.0001 respectively) and pT stage (p=0.046, p=0.004, p=0.001, respectively) in PC cases. All these markers were also associated with perineural, lymphovascular and extraprostatic invasion (p <0.05). In addition, a positive correlation was found between NGF and MMP-9 (p<0.0001, r=0.435), NGF and GDNF (p<0.0001, r=0.634), and GDNF and MMP-9 (p<0.0001, r=0.670) in PC cases. According to our results we suggest an interaction between NGF, GDNF and MMP-9 during the transition to malignancy in PC. Also this interaction may involve in regulating PC cell differentiation, tumor invasion, progression, and the agressiveness of PC.

Nerve Growth Factor Expression Is Not Associated with Perineural Invasion in Extrahepatic Cholangiocarcinoma

BACKGROUND

Although the presence of perineural invasion has been recognized as a poor prognostic factor in extrahepatic cholangiocarcinoma, the molecular mechanisms of perineural invasion in extrahepatic cholangiocarcinoma remain unclear. Nerve growth factor has been reported to be a candidate predictive biomarker of perineural invasion in some cancers.

AIM

To investigate the impact of intratumoral nerve growth factor expression in resected extrahepatic cholangiocarcinoma on survival.

METHODS

Intratumoral nerve growth factor expression was investigated immunohistochemically in 112 patients with resected extrahepatic cholangiocarcinoma. Associations between nerve growth factor expression and clinicopathological factors were statistically evaluated, and risk factors for poor survival were analyzed using univariate and multivariate analyses.

RESULTS

High and low nerve growth factor expression was observed in 62 (55%) and 50 (45%) patients, respectively. For all 112 patients, no significant correlation was found between nerve growth factor expression and presence of perineural invasion (P = 0.942). Moreover, nerve growth factor expression was not associated with recurrence-free survival (P = 0.861) and overall survival (P = 0.973). In multivariate analysis, lymph node metastasis (P = 0.004) was identified as an independent risk factor for early recurrence and the presence of perineural invasion (P = 0.002) and lymph node metastasis (P < 0.001) was identified as independent risk factors for poor survival.

CONCLUSIONS

Intratumoral nerve growth factor expression is not associated with perineural invasion or recurrence-free and overall survival in patients with resected extrahepatic cholangiocarcinoma.

CD271 is a functional and targetable marker of tumor-initiating cells in head and neck squamous cell carcinoma

Tumor-initiating cells (TICs) in squamous cell carcinoma of the head and neck (SCCHN) are best characterized by their surface expression of CD44. Although there is great interest in identifying strategies to target this population, no marker of these cells has been found to be functionally active. Here, we examined the expression of the purported marker of normal human oral epithelial stem cells, CD271. We show that CD271 expression is restricted to a subset of the CD44⁺ cells. Using xenograft assays, we show that the CD44⁺CD271⁺ subpopulation contains the most tumorigenic cells. Loss of CD271 function results in a block in the G2-M phase of the cell cycle and a profound negative impact on the capacity of these cells to initiate tumor formation in vivo. Incubation with recombinant NGF results in enhanced phosphorylation of Erk, providing additional evidence that CD271 is functionally active. Finally, incubation of SCCHN cells with antibody to CD271 results in decreased Erk phosphorylation and decreased tumor formation in vivo. Thus, our data are the first to demonstrate that CD271 more specifically identifies the TIC subpopulation within the CD44⁺ compartment in SCCHN and that this receptor is a functionally active and targetable molecule.

Nerve growth factor promotes killing of Leishmania donovani by macrophages through the induction of hydrogen peroxide

Visceral leishmaniasis is protozoonosis that occurs worldwide and still requires effective therapies with less toxicity. In this study, we examined the antileishmanial effect of nerve growth factor (NGF) using a murine infection model. NGF blocked the infection of macrophages by Leishmania donovani, which was completely cancelled by a hydrogen peroxide inhibitor. In vivo, not only did NGF show antileishmanial effects, but combination therapy of NGF and sodium stibogluconate synergistically exhibited the activity more potently than each monotherapy. These results indicate that NGF exerts antileishmanial effect by stimulating hydrogen peroxide production in macrophages and can be a novel therapy for leishmaniasis.

Clinical significance of nerve growth factor and tropomyosin-receptor-kinase signaling pathway in intrahepatic cholangiocarcinoma

AIM: To investigate the correlation between nerve growth factor-tropomyosin-receptor-kinase (NGF-TrkA) signaling pathway and prognosis in intrahepatic cholangiocarcinoma (IHCC).

METHODS: NGF and TrkA expression in 83 samples of IHCC was assessed by immunohistochemistry. Correlations between NGF-TrkA expression and clinicopathological features were analyzed by χ² test. Moreover, we evaluated the association between NGF-TrkA and overall survival by univariate and multivariate analysis. With experiments in vitro, we investigated the crucial role of NGF-TrkA on proliferation and invasion of IHCC cells with recombinant NGF-β stimulation.

RESULTS: We found that NGF and TrkA expression was significantly related with differentiation (P = 0.024) and intraneural invasion (P = 0.003), respectively. Additionally, double higher expression of NGF and TrkA was identified as an independent prognostic factor in IHCC (P = 0.003). Moreover, we demonstrated that NGF-TrkA signaling pathway can promote IHCC proliferation and invasion.

CONCLUSION: NGF-TrkA double higher expression is an independent prognostic factor in IHCC. NGF-TrkA pathway can promote IHCC progression, indicating that NGF-TrkA may become a potential drug target.