Protective effects of silymarin in glioblastoma cancer cells through redox system regulation.

BACKGROUND: Glioblastoma multiforme, a deadly form of brain tumor, is characterized by aggressive growth and poor prognosis. Oxidative stress, a disruption in the balance between antioxidants and oxidants, is a crucial factor in its pathogenesis. Silymarin, a flavonoid extracted from milk thistle, has shown therapeutic potential in inhibiting cancer cell growth, promoting apoptosis, and reducing inflammation. It also regulates oxidative stress. This study aims to investigate the regulatory effects of silymarin on oxidative stress parameters, especially the transcription factor Nrf2 and its related enzymes in GBM cancer cells, to develop a new anti-cancer compound with low toxicity. METHODS AND RESULTS: First, the cytotoxicity of silymarin on U-87 MG cells was investigated by MTT and the results showed an IC50 of 264.6 µM. Then, some parameters of the redox system were measured with commercial kits, and the obtained results showed that silymarin increased the activity of catalase and superoxide dismutase enzymes, as well as the total antioxidant capacity levels; while the malondialdehyde level that is an indicator of lipid peroxidation was decreased by this compound. The expression level of Nrf2 and HO-1 and glutaredoxin and thioredoxin enzymes were checked by real-time PCR method, and the expression level increased significantly after treatment. CONCLUSIONS: Our findings suggest that silymarin may exert its cytotoxic and anticancer effects by enhancing the Nrf2/HO-1 pathway through antioxidant mechanisms in U-87 MG cells.

Homology modeling, virtual screening, molecular docking, and ADME approaches to identify a potent agent targeting NK2R protein.

Neurokinin/tachykinin receptors are classified as the G-protein coupled receptor superfamily. The neurokinin 2 receptor (NK2R) is widely expressed in different tissues. NK2R is associated with a range of biological events, such as inflammation, smooth muscle contraction, intestinal motor functions, and asthma. Despite these diverse activities, no approved drugs targeting NK2R have been developed yet. Our study focuses on finding potential inhibitors for NK2R using virtual screening, molecular docking, and ADME (absorption, distribution, metabolism, and excretion) approaches. We used a homology modeling approach and AlphaFold DB to obtain the three-dimensional structure of mouse and human NK2R proteins, respectively. The homology model of NK2R was predicted using MODELLER v10.3 and further refined and validated using the 3Drefine tool and RAMPAGE server, respectively. Molecular docking was performed using a library of 910 structurally similar molecules to four NK1R antagonists: aprepitant, casopitant, fosaprepitant, and rolapitant. Molecular docking revealed six small molecules that displayed high Chemscore fitness scores, and binding energies with desirable ligand-NK2R interactions. The evaluation of the in silico ADME profile, solubility, and permeability of the ligand molecules has revealed that the small molecules are potentially nontoxic and have the chance of exhibiting biological activity after oral administration. Further experimental studies (in vitro and in vivo assays) are required to evaluate the effectiveness of these inhibitors as therapeutic targets.

Bio-synthesized selenium nanoparticles ameliorate Brain oxidative stress in Parkinson disease rat models.

AIM: Parkinson disease (PD) is a prevalent central nervous system degenerative condition that impacts elderly people. Recent clinical and experimental study findings have established oxidative stress as one of the main pathogeneses of PD. Selenium, a trace metals with antioxidant effects, might reverse the neurobehavioral impairments and oxidative stress in rats. Thus, the goal of this study was to ascertain if Selenium Nano Particles (SeNPs) are also effective to protect brain cells from oxidative stress or not. MAIN METHODS: SeNPs were synthesized utilizing Ascorbic acid and chitosan as a reducing and stabilizing agent. Next, eight groups (N: 6) of male Wistar rats were randomly assigned and injected by different dosage (0.1, 0,2, and 0.3 mg/kg) of Se and SeNP. Finally, to ascertain the protective benefits of SeNP on PD rats, behavioral evaluation, clinical symptoms, antioxidant activity, and oxidant levels were examined. KEY FINDINGS: According to the findings, PD rats' motor functions had developed by SeNP injection. Higher MDA levels and inhibited antioxidant activities (SOD, CAT, and GPX) in lesion group are highlighting the significant role of oxidative stress in dopaminergic neuron death and neurobehavioral abnormalities. SeNP also protect against oxidative stress as compared to the lesion group. The levels of MDA had greatly reduced while the activities of enzymes, TAC, and SeNP both had significantly increased. SIGNIFICANCE: By enhancing antioxidant activity, administration of SeNP can reduce the hazardous consequences of oxidative stress.

Effect of folic acid-linked chitosan-coated PLGA-based curcumin nanoparticles on the redox system of glioblastoma cancer cells.

OBJECTIVES: Oxidative stress is one of the carcinogenic mechanisms underlying the development of glioblastoma multiforme (GBM), a highly aggressive brain tumor type associated with poor prognosis. Curcumin is known to be an efficient antioxidant, anti-inflammatory, and anticancer compound. However, its poor solubility in water, inappropriate pharmacokinetics, and low bioavailability limit its use as an antitumor drug. We prepared PLGA-based curcumin nanoparticles changed with folic acid and chitosan (curcumin-PLGA-CS-FA) and evaluated its effects on GBM tumor cells' redox status. METHODS: The nanoprecipitation method was used to synthesize CU nanoparticles (CU-NPs). The size, morphology, and stability were characterized by DLS, SEM, and zeta potential analysis, respectively. The CU-NPs' toxic properties were studied by MTT assay and measuring the intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) concentrations. The study was completed by measuring the gene expression levels and activity of superoxide dismutase, catalase, glutaredoxin, and thioredoxin antioxidant enzymes. RESULTS: The size, polydispersity index, and zeta potential of CU-NPs were 77.27 nm, 0.29, and -22.45 mV, respectively. The encapsulation efficiency was approximately 98%. Intracellular ROS and MDA levels decreased after CU-NP treatment. Meanwhile, the CU-NPs increased gene expression and activity of superoxide dismutase, catalase, glutaredoxin, and thioredoxin antioxidant enzymes. CONCLUSION: CU-NPs might be effective in the prevention and treatment of glioblastoma cancer by modulating the antioxidant-oxidant balance.

The substance P/ neurokinin-1 receptor signaling pathway mediates metastasis in human colorectal SW480 cancer cells.

BACKGROUND: The substance P (SP)/neurokinin-1 receptor (NK1R) system, a critical metastatic signaling pathway, can be targeted by substance P antagonists to prevent its cancer-progressive impacts. In the current study, we aimed to investigate the carcinogenic activity of the SP/NK1R system in human SW480 colorectal cancer cells and study the antagonistic impact of aprepitant (AP) by measuring MMP-2 and MMP-9 enzymatic activity. METHODS: Different concentrations of SP, alone or mixed by AP, were utilized to treat SW480 cells to investigate the cells' viability and metastasis by applying Resazurin and Gelatin Zymography methods, respectively. The cells' metastatic response was analyzed by measuring the MMP-2 and MMP-9 in transcriptional and translational levels. Finally, the Scratch assay was carried out to evaluate the cells' metastatic response following the SP/AP treatment. RESULTS: A significant metastatic activity was observed in SW480 cells following incubation with the increasing SP doses by detecting MMP-2/MMP-9 enzyme activity, genes overexpression, and enhanced cell migration. This is while the AP treatment meaningfully diminished all the SP-mediated metastatic effects (p-Value < 0.001). CONCLUSIONS: According to the results, the SP/NKR1 signaling pathway can be considered one of the main metastatic effectors in human colorectal cancer. Therefore, AP might be suggested to be used as the SP antagonist and an efficient anti-metastatic drug.

Potential in vitro therapeutic effects of targeting SP/NK1R system in cervical cancer.

BACKGROUND: Cervical cancer, an aggressive gynecological cancer, seriously threatens women's health worldwide. It is recently reported that neuropeptide substance P (SP) regulates many tumor-associated processes through neurokinin-1 receptor (NK1R). Therefore, we used cervical cancer cell line (HeLa) to investigate the functional relevance of the SP/NK1R system in cervical cancer pathogenesis. METHODS: Cellular proliferation and cytotoxicity were analyzed by colorimetric MTT assay. Quantitative real-time PCR (qRT-PCR) was used to measure mRNA expression levels of desired genes. Cell cycle distribution and apoptosis were evaluated by flow cytometry. A wound-healing assay was employed to assess migration ability. RESULTS: We found that the truncated isoform of NK1R(NK1R-Tr) is the dominantly expressed form of the receptor in Hela cells. We also indicated that that SP increased HeLa cell proliferation while treatment with NK1R antagonist, aprepitant, inhibited HeLa cell viability in a dose and time-dependent manner. SP also alters the levels of cell cycle regulators (up-regulation of cyclin B1 along with downregulation of p21) and apoptosis-related genes (up-regulation of Bcl-2 along with downregulation of Bax) while aprepitant reversed these effects. Aprepitant also induced arrest within the G2 phase of the cell cycle and subsequent apoptosis. Furthermore, SP promoted the migrative phenotype of HeLa cells and increased MMP-2 and MMP-9 expression while aprepitant exposure significantly reversed these effects. CONCLUSION: Collectively, our results indicate the importance of the SP / NK1R system in promoting both proliferative and migrative phenotypes of cervical cancer cells and suggest that aprepitant may be developed as a novel treatment for combating cervical cancer.

Modulatory effect of berberine on plasma lipoprotein (or lipid) profile: a review.

Berberine is a bioactive isoquinoline alkaloid compound extracted from various medicinal plants, such as Barberry. Berberine shows various pharmacological properties that are mainly attributed to its anti-inflammatory and antioxidant effects. A growing body of evidence has shown that berberine influences cholesterol metabolism, and consequently, may ameliorate dyslipidemias and atherosclerosis. Plasma high-density lipoprotein cholesterol (HDL-C) is known to have an independent negative association with incident cardiovascular disease (CVD). However, several outcomes trials and genetic studies have failed to meet expecting the beneficial effects of elevating plasma HDL-C concentrations. Hence, investigations are currently focused on enhancing the functionality of HDL particles, independent of their plasma concentrations. HDL particles show various qualities because of a heterogeneous composition. Consistent with complex metabolism and composition, various biological functions are found for HDL, such as anti-inflammatory, antioxidant, anti-apoptotic, and anti-thrombotic activities. Protective effects of berberine may impact the functionality of HDL; therefore, the present literature review was intended to determine whether berberine can amplify HDL function. It was concluded that berberine may regulate markers of HDL activity, such as apo-AI, cholesterol efflux, LCAT, PON1, and S1P activities and levels. Consequently, berberine may recuperate conditions with dysfunctional HDL and, therefore, have the potential to emerge as a therapeutic agent. However, further human trials of berberine are warranted to evaluate its impact on HDL function and cholesterol metabolism.

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.

Selenium Effects on Oxidative Stress-Induced Calcium Signaling Pathways in Parkinson's Disease.

Parkinson's disease (PD) is a neurological disorder in which oxidative stress and reactive oxygen species productions are proposed to be involved in its pathogenesis. Despite considerable advancement in Selenium's (Se) molecular biology and metabolism, we do not know much about the cell type-specific pattern of Se distribution in the brain of PD humans and experimental animals. Although, there is plenty of evidence around the role of Se deficiency in PD's pathogenesis impacting lipid peroxidation and reducing glutathione (GSH) and glutathione peroxidase (GPX). It has been suggested that Se has an inducible role in selenium-dependent GPX activity in PD animals and humans. However, calcium as a second messenger regulates the neuron cells' essential activities, but its overloading leads to cellular oxidative stress and apoptosis. Therefore, Se's antioxidant role can affect calcium signaling and alleviate its complications. There are signs of Se and Selenoproteins incorporation in protecting stress oxidative in various pathways. In conclusion, there is convincing proof for the crucial role of Se and Calcium in PD pathogenesis. Supplementary Information: The online version contains supplementary material available at 10.1007/s12291-022-01031-1.

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.

Protective effects of BiP inducer X (BIX) against diabetic cardiomyopathy in rats.

Diabetic cardiomyopathy (DC) is associated with impaired endoplasmic reticulum (ER) function, development of ER stress, and induction of cardiac cell apoptosis. Preventive effects of BiP inducer X (BIX) were investigated against DC characteristic changes in a type 2 diabetes rat model. To establish diabetes, a high-fat diet and a single dose of streptozotocin were administered. Then, animals were assigned into the following groups: control, BIX, diabetic animals monitored for one, two, and three weeks. Diabetic rats were treated with BIX for one, two, and three weeks. Expressions of various ER stress and apoptotic markers were assessed by immunoblotting method. CHOP gene expression was assessed by Real-time PCR. Tissue expression of BiP was evaluated by immunohistochemistry method. Hematoxylin and eosin and Masson's trichrome staining were performed to assess histological changes in the left ventricle. Cardiac cell apoptosis was examined using TUNEL assay. BIX administration suppressed the activation of the ER stress markers and cleavage of procaspase-3 in the diabetic rats. Likewise, tissue expression of BiP protein was increased, while CHOP mRNA levels were decreased. These results were accompanied by reducing cardiac fibrosis and myocardial cell apoptosis suggesting protective effects of BIX against the development of DC by decreasing cardiomyocyte apoptosis and fibrosis.

Protective effects of propolis on hepatic steatosis and fibrosis among patients with nonalcoholic fatty liver disease (NAFLD) evaluated by real-time two-dimensional shear wave elastography: A randomized clinical trial.

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, while no drugs have been approved for its treatment. The pieces of evidence indicate that propolis as a novel anti-inflammatory agent might be a promising candidate to treat NAFLD. We aimed to evaluate the efficacy of propolis on hepatic steatosis and fibrosis in patients with NAFLD. This randomized clinical trial was conducted on 54 patients with NAFLD. Patients were randomly assigned to receive propolis tablets at a dose of 250 mg twice daily for 4 months or placebo. The improvement in hepatic steatosis and fibrosis was evaluated using two-dimensional shear wave elastography. Improvement in the hepatic steatosis was significantly higher in the propolis group than the placebo group, even after adjustment for baseline value and changes in weight, energy intake, and physical activity (odds ratio [OR]: 5.67; 95% confidence intervals [CI]: 1.41-22.8; p = .014). A significant reduction was observed on the liver stiffness in the propolis group (-0.65 ± 0.56 kPa; p = .001), whereas it increased in the placebo group (0.27 ± 0.59 kPa; p = .037). Also, the intake of propolis significantly decreased high-sensitivity C-reactive protein (hs-CRP) levels compared with the placebo group (-0.371; 95%CI: -0.582 to -0.16 mg/L; p = .01). Changes in serum levels of fasting blood sugar, alanine aminotransferase, aspartate aminotransferase, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, cholesterol, and triglyceride did not differ significantly between the two groups (p > .05). There was no significant improvement in insulin resistance in both groups (p > .05). Propolis seems to have protective effects on hepatic steatosis and fibrosis and to reduce the serum levels of hs-CRP in patients with NAFLD.

Effects of Rhus coriaria L. hydroalcoholic extract on the lipid and antioxidant profile in high fat diet-induced hepatic steatosis in rats.

Oxidative stress is related to increased fat deposition in the liver, known as hepatic steatosis. The present study is an evaluation of the anti-oxidative and antihyperlipidemic effects of the hydroalcoholic extract of Rhus coriaria L. (HARE) in rats on a high-fat diet (HFD). Twenty male Wistar rats were divided into four groups: control, HFD, HFD + HARE 50 mg/kg/day, and HFD + HARE 250 mg/kg/day for 12 weeks. Animals were weighed weekly and treated with the HARE extract for 12 weeks by gavage. Subsequently, the histopathological changes, oxidative markers, and lipid profile were evaluated. Statistical analysis was performed using the one-way analysis of variance (ANOVA) for multiple comparisons. First, the active ingredients of the extract were determined by HPLC. Then, the levels in the serum lipid profile (TG, cholesterol, HDL, and LDL) in rats fed with the HFD + HARE were analyzed where a significant reduction was observed. The HFD proved to increase the activity of the liver enzymes, the serum lipid levels, and the malondialdehyde (MDA) level. The ferric-reducing antioxidant activity power (FRAP), catalase (CAT), and superoxide dismutase (SOD) catalytic activity were reduced in the liver homogenate of HFD rats compared to the controls. Additionally, the aforementioned liver enzymes activities were reduced in response to HARE. Evaluation of oxidative stress determined a reduction in the MDA level while a raised FRAP was confirmed. In accordance with the present results, histopathological observations have also demonstrated that HARE ameliorated grade-1 hepatic steatosis induced by HFD. Taken together, the findings of this study introduce HARE as a future potential therapeutic agent in treating hepatic steatosis and reducing oxidative damages of an HFD in the liver.

Role of tumor microenvironment in the regulation of PD-L1: A novel role in resistance to cancer immunotherapy.

Tumor evasion from the host immune system is a substantial strategy for tumor development and survival. The expression of many immune checkpoint proteins in cancer cells is a mechanism by which tumor cells escape from the immune system. Among the well-known immune checkpoints that can tremendously affect tumor development and cancer therapy are the programmed death-ligand-1/programmed death-1 (PD-L1/PD-1). To tackle this phenomenon and improve the therapeutic strategies in cancer treatment, the blockade of the PD-L1/PD-1 pathway is introduced as a target, but the therapeutic advantage of PD L1/PD-1 blockade has not fulfilled the expectations. This condition may be associated with a different type of resistance in a considerable number of patients. A crucial issue to conquer resistance against immune checkpoint blockade therapy is to understand how PD-L1 level is regulated. However, the mechanisms by which the PD-L1 expression is regulated are complicated, and they can occur at different levels from signaling pathways to posttranscriptional levels. For example, various transcriptional factors, such as hypoxia-inducible factor-1, nuclear factor-κΒ, interferon-γ, STAT3, MYC, and AP-1 can regulate the PD-L1 distribution at the transcriptional level. Herein, we tried to focus on the most important regulatory mechanisms of PD-L1 by inducible agents in the tumor cells, such as signaling pathways, transcriptional factors, and posttranscriptional factors. Finally, these approaches may open up new windows for targeting tumor immune evasion and suggest the novel suppressors of PD-L1 for efficient therapeutics.

Cytokines as potential combination agents with PD-1/PD-L1 blockade for cancer treatment.

Immunotherapy has caused a paradigm shift in the treatment of several malignancies, particularly the blockade of programmed death-1 (PD-1) and its specific receptor/ligand PD-L1 that have revolutionized the treatment of a variety of malignancies, but significant durable responses only occur in a small percentage of patients, and other patients failed to respond to the treatment. Even those who initially respond can ultimately relapse despite maintenance treatment, there is considerable potential for synergistic combinations of immunotherapy and chemotherapy agents with immune checkpoint inhibitors into conventional cancer treatments. The clinical experience in the use of cytokines in the clinical setting indicated the efficiency of cytokine therapy in cancer immunotherapy. Combinational approaches to enhancing PD-L1/PD-1 pathways blockade efficacy with several cytokines such as interleukin (IL)-2, IL-15, IL-21, IL-12, IL-10, and interferon-α (IFN-α) may result in additional benefits. In this review, the current state of knowledge about PD-1/PD-L1 inhibitors, the date in the literature to ascertain the combination of anti-PD-1/PD-L1 antibodies with cytokines is discussed. Finally, it is noteworthy that novel therapeutic approaches based on the efficient combination of recombinant cytokines with the PD-L1/PD-1 blockade therapy can enhance antitumor immune responses against various malignancies.

The immunomodulatory effects of tachykinins and their receptors.

Tachykinins (TKs) are a family of neuropeptides mainly expressed by neuronal and non-neuronal cell types, especially immune cells. Expression of TKs receptors on immune cell surfaces, their involvement in immune-related disorders, and therefore, understanding their immunomodulatory roles have become of particular interest to researchers. In fact, the precise understanding of TKs intervention in the immune system would help to design novel therapeutic approaches for patients suffering from immune disorders. The present review summarizes studies on TKs function as modulators of the immune system by reviewing their roles in generation, activation, development, and migration of immune cells. Also, it discusses TKs involvement in three main cellular mechanisms including inflammation, apoptosis, and proliferation.

New insight into the role of substance P/neurokinin-1 receptor system in breast cancer progression and its crosstalk with microRNAs.

The neuropeptide substance P (SP) triggers a variety of tumor-promoting signaling pathways through the activation of neurokinin-1receptor (NK1R), a class of neurokinin G protein-coupled receptors superfamily. Recent researches in our and other laboratories have shown the overexpression of both SP and NK1R in breast cancer (BC) patients. SP/NK1R signaling is strongly implicated in the pathogenesis of BC through affecting cell proliferation, migration, metastasis, angiogenesis, and resistance. Therefore, SP/NK1R signaling responses must be rigorously regulated; otherwise, they would contribute to a more aggressive BC phenotype. Recently, microRNAs (miRNAs) as a specific class of epigenetic regulators have been shown to regulate NK1R and thus, controlling SP/NK1R signaling responses in BC. This review summarizes the current knowledge of the role of SP/NK1R signaling and its therapeutic potentials in BC. We also provide an overview regarding the effects of miRNA-mediated NK1R regulatory mechanisms in controlling BC tumorigenesis to gain a clearer view and thus better management of cancer.

Genotypic and phenotypic characterization of Mycobacterium tuberculosis resistance against fluoroquinolones in the northeast of Iran.

BACKGROUND: Fluoroquinolones are broad-spectrum antibiotics that are recommended, and increasingly important, for the treatment of multidrug-resistant tuberculosis (MDR-TB). Resistance to fluoroquinolones is caused by mutations in the Quinolone Resistance Determining Region (QRDR) of gyrA and gyrB genes of Mycobacterium tuberculosis. In this study, we characterized the phenotypic and genotypic resistance to fluoroquinolones for the first time in northeast Iran. METHODS: A total of 123 Mycobacterium tuberculosis isolates, including 111 clinical and 12 collected multidrug-resistant isolates were studied. Also, 19 WHO quality control strains were included in the study. The phenotypic susceptibility was determined by the proportion method on Löwenstein-Jensen medium. The molecular cause of resistance to the fluoroquinolone drugs ofloxacin and levofloxacin was investigated by sequencing of the QRDR region of the gyrA and gyrB genes. RESULTS: Among 123 isolates, six (4.8%) were fluoroquinolone-resistant according to phenotypic methods, and genotypically three of them had a mutation at codon 94 of the gyrA gene (Asp→ Gly) which was earlier reported to cause resistance. All three remaining phenotypically resistant isolates had a nucleotide change in codon 95. No mutations were found in the gyrB gene. Five of the 19 WHO quality control strains, were phenotypically fluoroquinolone-resistant, four of them were genotypically resistant with mutations at codon 90, 91 of the gyrA gene and one resistant strain had no detected mutation. CONCLUSIONS: Mutation at codon 94 of the gyrA gene, was the main cause of fluoroquinolone resistance among M. tuberculosis isolates in our region. In 3/6 fluoroquinolone-resistant isolates, no mutations were found in either gyrA or gyrB. Therefore, it can be concluded that various other factors may lead to fluoroquinolone resistance, such as active efflux pumps, decreased cell wall permeability, and drug inactivation.

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.

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

Colorectal cancer (CRC) is known as the most common form of malignancies in the world and its occurrence is annually increasing. Due to the relatively high death rates in patients, finding better diagnostic and prognostic factors are required. Substance P (SP) belongs to the tachykinin family that acts as an immunomodulator by binding to the neurokinin-1 receptor (NK1R). The interaction of SP with NK1R might be involved in tumor cell proliferation, angiogenesis, and migration. Hence, this study was aimed to evaluate the serum SP level and tissue distribution of NK1Rs in CRC. Also, we assessed the relationship between tissue distribution of NK1R and some different tumor characteristics, including tumor size, and lymph node status. Recruiting 38 patients primarily diagnosed with CRC, the tissue distribution of NK1R was immunohistochemically evaluated in tumor tissues and their adjacent normal tissue. The serum level of SP was measured using an ELISA method in both cases and healthy control group. The SP value was significantly increased in the serum of patients in comparison with the healthy group (p = 0.001). Tumor tissues expressed a higher number of NK1R than adjacent normal tissues (p = 0.01) considering both the percentage of stained cells and intensity of staining. However, there was not any statistically significant relevance between NK1R distribution and tumor characteristics. The SP/NK1R system is involved in tumorigenesis of CRC, and might be suggested as a potent prognostic or diagnostic factor, or a new target in the treatment of CRC.