Evaluation of serum level of substance P and tissue distribution of NK-1 receptor in colorectal cancer

The combined anti-tumor effects of 5-fluorouracil and neurokinin receptor inhibitor, aprepitant, against colorectal cancer: In vitro and in vivo study

BACKGROUND

Colorectal cancer (CRC) is one of the world's largest health concerns with growing global incidence and mortality. The potential value of the neurokinin-1 receptor as a therapeutic target has been reported in several tumor types, including CRC. Here we examined the potential anti-tumor effects of a clinically approved neurokinin-1 receptor antagonist, aprepitant, alone and its combination with 5-Fluorouracil (5-FU) as a first choice CRC chemotherapeutic drug, in both in vitro and in vivo models of CRC.

METHODS

MTT assay was employed for assessing cell proliferation. mRNA expression levels were determined by quantitative real-time PCR (qRT-PCR). Flow cytometric analysis of apoptosis was performed using an Annexin-V/propidium iodide assay kit. We finally conducted an in vivo experiment in a mouse model of CRC to confirm the in vitro antiproliferative activity of aprepitant and 5-FU.

RESULTS

We found that aprepitant and 5-FU significantly reduced CRC cell viability. The combination of drugs exhibited potent synergistic growth inhibitory effects on CRC cells. Moreover, aprepitant and 5-FU induced apoptosis and altered the levels of apoptotic genes (up-regulation of Bax, and p53 along with downregulation of Bcl-2). Importantly, the aprepitant and 5-FU combination showed a more pronounced impact on apoptosis and associated genes than either of the agents alone. Furthermore, aprepitant reduced tumor growth in vivo and led to significantly longer survival time, and this effect was more prominent when using the aprepitant and 5-FU combination.

CONCLUSIONS

Collectively, combinatory treatment with aprepitant and 5-FU potentially exerts synergistic growth inhibition and apoptosis induction in CRC, deserving further consideration as a novel strategy for CRC patients.

The Repurposing of Non-Peptide Neurokinin-1 Receptor Antagonists as Antitumor Drugs: An Urgent Challenge for Aprepitant

The substance P (SP)/neurokinin-1 receptor (NK-1R) system is involved in cancer progression. NK-1R, activated by SP, promotes tumor cell proliferation and migration, angiogenesis, the Warburg effect, and the prevention of apoptosis. Tumor cells overexpress NK-1R, which influences their viability. A typical specific anticancer strategy using NK-1R antagonists, irrespective of the tumor type, is possible because these antagonists block all the effects mentioned above mediated by SP on cancer cells. This review will update the information regarding using NK-1R antagonists, particularly Aprepitant, as an anticancer drug. Aprepitant shows a broad-spectrum anticancer effect against many tumor types. Aprepitant alone or in combination therapy with radiotherapy or chemotherapy could reduce the sequelae and increase the cure rate and quality of life of patients with cancer. Current data open the door to new cancer research aimed at antitumor therapeutic strategies using Aprepitant. To achieve this goal, reprofiling the antiemetic Aprepitant as an anticancer drug is urgently needed.

Neuropeptide substance P: A promising regulator of wound healing in diabetic foot ulcers

In the past, neuropeptide substance P (SP) was predominantly recognized as a neuroinflammatory factor, while its potent healing activity was overlooked. This paper aims to review the regulatory characteristics of neuropeptide SP in both normal and diabetic wound healing. SP actively in the regulation of wound healing-related cells directly and indirectly, exhibiting robust inflammatory properties, promoting cell proliferation and migration and restoring the activity and paracrine ability of skin cells under diabetic conditions. Furthermore, SP not only regulates healing-related cells but also orchestrates the immune environment, thereby presenting unique and promising application prospects in wound intervention. As new SP-based preparations are being explored, SP-related drugs are poised to become an effective therapeutic intervention for diabetic foot ulcers (DFU).

Prognostic Significance of Substance P and Neurokinin-1 Receptor in Bladder Cancer

Background

Bladder cancer is one of the most common genitourinary cancers with significant mortality. Finding reliable tumor markers and potential drug targets can improve early diagnosis, prognosis, and more effective therapeutic protocols. Previous studies have reported the involvement of the substance P (SP)/neurokinin-1 receptor (NK-1R) system in cancers. The potential prognostic role and the interaction of SP and NK-1R in bladder tumor are yet to be elucidated.

Methods

Serum samples from 22 primarily diagnosed patients with bladder cancer as well as 22 healthy controls were examined for SP level using ELISA method. Tissue distribution of NK-1R in tumor samples and their adjacent normal tissues was evaluated through immunohistochemistry.

Results

Serum SP levels in patients with bladder cancer were higher than the healthy group (p< 0.001) and had a significant correlation with NK-1R staining intensity (p< 0.001), percentage of stained cells (p< 0.001), and NK-1R tissue distribution. Also, the immunoreactivity of NK-1R in cancer samples increased significantly without correlation with tumor characteristics. However, no significant association was found between SP and NK-1R levels with clinical characteristics including tumor size (p= 0.33), tumor stage (p= 0.29), grade (p= 0.93), NK-1R staining intensity (p= 0.53), and percentage of stained cells (p= 0.32).

Discussion

According to our findings, despite the lack of association between SP and NK-1R with clinical characteristics of bladder cancer, their serum levels were higher in patients with bladder cancer. Further studies are needed to confirm the potential prognostic role of SP and NK-1R in bladder cancer.

The effect of substance P and its specific antagonist (aprepitant) on the expression of MMP-2, MMP-9, VEGF, and VEGFR in ovarian cancer cells

BACKGROUND

Substance P (SP) has a crucial role in cancer initiation and progression via binding to its specific receptor (NK1R). Various evidence confirmed the overexpression of NK1R and SP in the tissue of multiple cancers, including ovarian cancer. Despite numerous studies, the mechanism of the SP/NK1R system on migration and angiogenesis of ovarian cancer cells has not yet been deciphered. In this study, considering the critical factors in cell migration (MMP-2, MMP-9) and angiogenesis (VEGF, VEGFR), we investigated the possible mechanism of this system in inducing migration and angiogenesis of ovarian cancer cells.

METHODS AND RESULTS

First, the resazurin assay was conducted to evaluate the cytotoxic effect of aprepitant (NK1R antagonist) on the viability of A2780 ovarian cancer cells. After that, the impact of this system and aprepitant on the mRNA expression of the factors mentioned above were studied using RT-PCR. Besides, the scratch assay was performed to confirm the effect of the SP/NK-1R system and aprepitant on cell migration. Our results implied that this system induced cell migration and angiogenesis by increasing the mRNA expression of MMP-2, MMP-9, VEGF, and VEGFR. The obtained results from the scratch assay also confirmed the positive effect of this system on cell migration. Meanwhile, the blocking of NK1R by aprepitant suppresses the SP effects on cell migration and angiogenesis.

CONCLUSIONS

Overall, the SP/NK1R system plays a vital role in ovarian cancer progression, and the inhibition of NK1Rusing aprepitant could inhibit the spread of ovarian cancer cells through metastasis and angiogenesis.

Multi-Omics Prognostic Signatures Based on Lipid Metabolism for Colorectal Cancer

Background: The potential biological processes and laws of the biological components in malignant tumors can be understood more systematically and comprehensively through multi-omics analysis. This study elaborately explored the role of lipid metabolism in the prognosis of colorectal cancer (CRC) from the metabonomics and transcriptomics.

Methods: We performed K-means unsupervised clustering algorithm and t test to identify the differential lipid metabolites determined by liquid chromatography tandem mass spectrometry (LC-MS/MS) in the serum of 236 CRC patients of the First Hospital of Jilin University (JLUFH). Cox regression analysis was used to identify prognosis-associated lipid metabolites and to construct multi-lipid-metabolite prognostic signature. The composite nomogram composed of independent prognostic factors was utilized to individually predict the outcome of CRC patients. Glycerophospholipid metabolism was the most significant enrichment pathway for lipid metabolites in CRC, whose related hub genes (GMRHGs) were distinguished by gene set variation analysis (GSVA) and weighted gene co-expression network analysis (WGCNA). Cox regression and least absolute shrinkage and selection operator (LASSO) regression analysis were utilized to develop the prognostic signature.

Results: Six-lipid-metabolite and five-GMRHG prognostic signatures were developed, indicating favorable survival stratification effects on CRC patients. Using the independent prognostic factors as variables, we established a composite nomogram to individually evaluate the prognosis of CRC patients. The AUCs of one-, three-, and five-year ROC curves were 0.815, 0.815, and 0.805, respectively, showing auspicious prognostic accuracy. Furthermore, we explored the potential relationship between tumor microenvironment (TME) and immune infiltration. Moreover, the mutational frequency of TP53 in the high-risk group was significantly higher than that in the low-risk group (p < 0.001), while in the coordinate mutational status of TP53, the overall survival of CRC patients in the high-risk group was significantly lower than that in low-risk group with statistical differences.

Conclusion: We identified the significance of lipid metabolism for the prognosis of CRC from the aspects of metabonomics and transcriptomics, which can provide a novel perspective for promoting individualized treatment and revealing the potential molecular biological characteristics of CRC. The composite nomogram including a six-lipid-metabolite prognostic signature is a promising predictor of the prognosis of CRC patients.

Aprepitant Promotes Caspase-Dependent Apoptotic Cell Death and G2/M Arrest through PI3K/Akt/NF-κB Axis in Cancer Stem-Like Esophageal Squamous Cell Carcinoma Spheres

The antagonists of the neurokinin-1 receptor (NK1R) are known for their anti-inflammatory, anxiolytic, antiemetic, and anticancer activities. Aprepitant, a nonpeptide NK1R antagonist, is used in nausea and vomiting, the most common side effects of cancer chemotherapy in patients. It has been established that NK1R activation by substance P (SP), which links cancer promotion and progression to a neurokinin-mediated environment, became one mechanism that corresponds to the mitogenesis of tumor cells. Therefore, this study is aimed at explaining and evaluating the anticancer impacts of aprepitant on esophageal squamous cancer cell (ESCC) spheres by using in vitro experiments, such as resazurin, ROS, annexin-V binding, RT-PCR, and Western blot analysis. As a result, we showed that aprepitant had strong antiproliferative and cytotoxic effects on ESCC cell spheres. Also, aprepitant caused significant G2-M cell cycle arrest depending on concentration increase. Further, exposure of cells to this agent resulted in caspase -8/-9-dependent apoptotic pathway activation by modifying the expression of genes involved in apoptosis. Besides, treatment of the cells by aprepitant abrogates of the PI3K/Akt pathway, as shown by reducing the level of Akt, induces apoptotic cell death. In summary, pharmacological inhibition of NK1R with aprepitant seems to have a significant chance of treating ESCC as a single agent or in conjunction with other chemotherapeutic drugs.

The SP/NK1R System-Mediated ROS Generation in GBM Cells through Inhibiting Glutaredoxin Protein

Altered redox balance is among the main contributing factors developing glioblastoma multiforme (GBM), a highly aggressive grade IV brain tumor. Neuropeptide substance P (SP) plays a key role in modifying the cellular redox environment by activating the neurokinin-1 receptor (NK1R). In this study, we aimed to investigate the redox-modulating properties of both SP and a commercially available NK1R antagonist, aprepitant in GBM cells. To detect the effect of aprepitant on the viability of U87 glioblastoma cells, resazurin assay was applied. The level of intracellular ROS was assessed using 2′,7′-dichlorodihydrofluorescein diacetate (H2DCFDA) assay. The expression of glutaredoxin, a well-known redox-active protein, was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Concurrently, the activity of glutaredoxin was also analyzed by a commercial kit (ZellBio GmbH). We found that SP increased the intracellular levels of reactive oxygen species (ROS) in U87 GBM cells, and aprepitant remarkably decreased this effect. We also explored the effects of SP/NK1R signaling on the glutaredoxin system as a major cellular redox buffer in GBM cells. SP reduced both expression and enzymatic activity of glutaredoxin, and these effects were significantly decreased by aprepitant. In conclusion, our results suggest a possible involvement of SP/NK1R signaling in GBM pathogenesis through oxidative stress and offering new insight for the application of aprepitant as a redox-modulating strategy in GBM patients.

Investigation of the Role of Neurokinin-1 Receptor Inhibition Using Aprepitant in the Apoptotic Cell Death through PI3K/Akt/NF-κB Signal Transduction Pathways in Colon Cancer Cells

Background

Colorectal cancer (CRC) is recognized as one of the most common malignancies with a high mortality rate worldwide, supporting the necessity for an effective novel antitumor drug to improve current therapy's effectiveness. Substance P (SP) is the essential member of the tachykinins (TKs) family, which binds to the specific receptors, known as neurokinin-1 receptor (NK1R), exerting its multiple influences such as tumor cell proliferation, angiogenesis, and metastasis. Aprepitant, as a specific NK1R antagonist, is suggested as a novel antitumor agent, promoting apoptotic processes in tumor cells; however, the exact antitumor mechanism of aprepitant on molecular signaling in CRC is not entirely known.

Method

The resazurin assay was conducted to assess the cytotoxic effects of aprepitant on the viability of the CRC cell line (SW480). The level of reactive oxygen species (ROS) was measured after 24-hour treatment with SP and aprepitant. PI/annexin V-FITC staining was conducted to assess apoptosis. Also, the expression of NF-κB antiapoptotic target genes and proapoptotic p53 target genes was measured by real-time- (RT-) PCR assay. Western blotting assay was performed to determine the expression of PI3k/AKT/NF-κB proteins.

Results

We found that aprepitant stimulates apoptotic cell death and attenuates the PI3K/Akt pathway and its downstream proapoptotic target gene, including NF-κB in SW480 cells. Also, the obtained results from the quantitative RT-PCR assay showed that aprepitant could decrease the level of mRNA of NF-κB antiapoptotic target genes.

Conclusion

Towards this end, this study suggests that SP/NK1R system plays a vital role in the development of CRC, and pharmaceutical targeting of NK1R using aprepitant might be a promising treatment against CRC.

Cross-talk between non-coding RNAs and PI3K/AKT/mTOR pathway in colorectal cancer

Colorectal cancer (CRC) is the third commonest cancer globally, with metastasis being the reason for cancer-associated mortality. Much is still unknown biochemically about CRC, and with current treatments that are not wholly effective over time, new therapeutics are urgently needed. Emerging evidence has shown the importance of non-coding RNAs such as lncRNAs and miRNAs functions in the development and progression of CRC. However, the exact underlying mechanism of these types of RNAs in CRC is still mostly unknown. PI3K/AKT/mTOR pathway contributes to many cellular processes, and dysregulation of this pathway frequently occurs in cancers. In this review, the authors have mostly focused on the significant non-coding RNAs regulators of the PI3K/AKT/mTOR pathway and their contribution to the development or inhibition of CRC and their potential as diagnostic or therapeutic targets in CRC treatment.

The Effect of SP/NK1R on the Expression and Activity of Catalase and Superoxide Dismutase in Glioblastoma Cancer Cells

Introduction

Glioblastoma is the most malignant brain tumor with different therapeutic protocols, including surgery, radiotherapy, and chemotherapy. Substance P (SP), a peptide released by sensory nerves, increases cellular excitability by activating the neurokinin-1 receptor (NK1R) in several human tumor cells. Aprepitant is a potent and long-lasting NK1R antagonist, considered a new agent for inhibiting proliferation and induction of apoptosis in malignant cells. This study aimed to evaluate the effects of the SP/NK1R system on the expression and activity of catalase and superoxide dismutase (SOD) in the glioblastoma U87 cancer cell line.

Methods

Cytotoxicity was measured by the resazurin test, 24 hours after treatment, with increasing aprepitant concentrations. The production of reactive oxygen species (ROS) was also measured 24 hours after treatment with SP and aprepitant. Enzymes activity of catalase and SOD was measured using the corresponding assay kits. Real-time PCR also measured their expression.

Results

Aprepitant significantly reduced the viability of U87 cells in a concentration-dependent manner. ROS production was significantly reduced, and the activity of catalase and SOD increased after treatment with aprepitant. The expression of catalase and SOD enzymes also increased significantly in the presence of aprepitant.

Conclusion

The present study showed that aprepitant inhibited SP's oxidizing effects via inducing the antioxidant effects of catalase and SOD in the U87 cell line. Therefore, this drug might be introduced as a potential candidate for controlling glioblastoma cancer in animal models and clinical trials.

Pathogenic role of the SP/ NK1R system in GBM cells through inhibiting the thioredoxin system

OBJECTIVES

Glioblastoma multiforme (GBM), a highly aggressive Grade IV brain tumor, is a significant public health issue due to its poor prognosis and incurability. Neuropeptide substance P (SP) plays a critical role in GBM tumor growth and development via activation of neurokinin-1receptor (NK1R). Moreover, SP is a pro-oxidant factor contributing to oxidative stress in various cell types. However, the link between SP and oxidative stress in cancer cells is not fully investigated. Here, we aimed to identify the effects of SP and NK1R antagonist, aprepitant, on the redox status of GBM cells.

MATERIALS AND METHODS

Resazurin assay was employed to determine the effect of aprepitant on viability of U87 glioblastoma cells. 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) assay was employed to measure the levels of intracellular reactive oxygen species (ROS). A quantitative real-time polymerase chain reaction was applied to measure the expression of proteins of the thioredoxin system. Commercial kits (ZellBio GmbH) were also used to measure the enzymatic activity of these proteins.

RESULTS

We found that SP increased ROS level in U87 GBM cells, and aprepitant significantly reduced this effect. Furthermore, we found that SP could also affect the thioredoxin system, a central antioxidant enzyme defense system. SP reduced both expression and enzymatic activity of the thioredoxin system's proteins, Trx and thioredoxin reductase (TrxR) and these effects were significantly reduced by aprepitant.

CONCLUSION

Our results indicated that SP activation of NK1R represented a link between oxidative stress and GBM and highlighted the need for further validations in future studies.

Substance P accelerates the progression of human esophageal squamous cell carcinoma via MMP-2, MMP-9, VEGF-A, and VEGFR1 overexpression

Tachykinins such as Substance P (SP) are a group of neuropeptides that are involved in cancer development. Neurokinin-1 receptor (NK-1R) is the main tachykinin receptor mediating the effects of SP, which is overexpressed in human esophageal squamous cell carcinoma (ESCC) and other malignant tissues. However, the effects of SP/NK-1R system on the migration of esophageal cancer cells and angiogenesis is not clear yet. This study seeks to obtain data to address these research gaps. In order to assess the effects of the FDA-approved aprepitant drug, a commercially available NK-1R antagonist, on the viability of KYSE-30 ESCC cells, resazurin assay was performed. The influence of SP/NK-1R system on the migration potential of these cells was examined using scratch assay. The effects of this system on the expression levels of metastatic factors were also examined by RT-PCR and western blot analyses. The half-maximal inhibitory concentration (IC₅₀) value for KYSE-30 cells treated with aprepitant found to be 29.88 μM. Treatment with SP significantly promoted KYSE-30 esophageal cancer cell migration, and aprepitant blocked this effect. In addition, SP significantly induced the expression of matrix metalloproteinase-2 (MMP-2), MMP-9, vascular endothelial growth factor-A (VEGF-A), and VEGF receptor1 (VEGFR1) in the cells, whereas aprepitant inhibited the up-regulation effects caused by SP. SP plays important roles in the development of human esophageal squamous cell carcinoma by promoting cancer cell invasion and enhancing the expression of factors involved in cellular migration and angiogenesis, which can be blocked by the NK-1R antagonist, aprepitant.