Folate Analogue Research Articles

Overview of Dual-Acting Drug Methotrexate in Different Neurological Diseases, Autoimmune Pathologies and Cancers

Methotrexate, a structural analogue of folic acid, is one of the most effective and extensively used drugs for treating many kinds of cancer or severe and resistant forms of autoimmune diseases. In this paper, we take an overview of the present state of knowledge with regards to complex mechanisms of methotrexate action and its applications as immunosuppressive drug or chemotherapeutic agent in oncological combination therapy. In addition, the issue of the potential benefits of methotrexate in the development of neurological disorders in Alzheimer’s disease or myasthenia gravis will be discussed.

Pralatrexate injection for the treatment of patients with relapsed or refractory peripheral T-cell lymphoma

ABSTRACT Introduction Peripheral T cell lymphomas (PTCL) are a heterogenous group of lymphoproliferative disorders which are generally not curable with conventional chemotherapy and associated with inferior outcomes. Pralatrexate is a novel folate analog, the first FDA approved drug) for the treatment of relapsed/refractory (R/R) PTCL. Areas covered This paper provides a comprehensive review of PubMed literature describing the use of pralatrexate in R/R peripheral T-cell lymphoma. Pharmacokinetics and mechanism of action of pralatrexate are discussed as well as its clinical efficacy and safety in comparison to other agents available in R/R PTCL. Expert opinion Pralatrexate is an active agent in relapsed/refractory PTCL with lower response rates seen in patients with angioimmunoblastic T cell lymphomas. Mucositis is the most frequently observed adverse event and this can be mitigated by the use of leucovorin along with cyanocobalamin and folic acid.

5-Aminouracil and other inhibitors of DNA replication induce biphasic interphase\u2013mitotic cells in apical root meristems of Allium cepa

Key messageInduction of biphasic interphase–mitotic cells and PCC is connected with an increased level of metabolism in root meristem cells of Allium cepa.Previous experiments using primary roots of Allium cepa exposed to low concentrations of hydroxyurea have shown that long-term DNA replication stress (DRS) disrupts essential links of the S–M checkpoint mechanism, leading meristem cells either to premature chromosome condensation (PCC) or to a specific form of chromatin condensation, establishing biphasic organization of cell nuclei with both interphase and mitotic domains (IM cells). The present study supplements and extends these observations by describing general conditions under which both abnormal types of M-phase cells may occur. The analysis of root apical meristem (RAM) cell proliferation after prolonged mild DRS indicates that a broad spectrum of inhibitors is capable of generating PCC and IM organization of cell nuclei. These included: 5-aminouracil (5-AU, a thymine antagonist), characterized by the highest efficiency in creating cells with the IM phenotype, aphidicolin (APH), an inhibitor of DNA polymerase α, 5-fluorodeoxyuridine (FUdR), an inhibitor of thymidylate synthetase, methotrexate (MTX), a folic acid analog that inhibits purine and pyrimidine synthesis, and cytosine arabinoside (Ara-C), which inhibits DNA replication by forming cleavage complexes with topoisomerase I. As evidenced using fluorescence-based click chemistry assays, continuous treatment of onion RAM cells with 5-AU is associated with an accelerated dynamics of the DNA replication machinery and significantly enhanced levels of transcription and translation. Furthermore, DRS conditions bring about an intensified production of hydrogen peroxide (H2O2), depletion of reduced glutathione (GSH), and some increase in DNA fragmentation, associated with only a slight increase in apoptosis-like programmed cell death events.

Glutamic acid-coated Fe3O4 nanoparticles for tumor-targeted imaging and therapeutics.

We have developed surface functionalised Fe3O4 magnetic nanoparticles (MNPs) based system that can be used for tumor-targeted multimodal therapies and MR imaging. Biocompatible, non-essential amino acid (glutamic acid) was introduced onto the surface of Fe3O4 MNPs to provide functional sites for binding of chemotherapeutic drugs. These glutamic acid-coated Fe3O4 MNPs (GAMNPs) exhibit good water-dispersibility, magnetic responsivity and pH dependent charge conversal feature. The magnetic core as well as organic shell of GAMNPs was characterized by XRD, TEM, DLS, FTIR, PPMS and UV-visible spectroscopy and zeta-potential analyzer etc. The broad spectrum anticancer drugs, doxorubicin hydrochloride (DOX) and methotrexate (MTX) were electrostatically and covalently conjugated to the surface of GAMNPs, respectively for combination chemotherapy. These dual drugs loaded system (DOX-MTX-GAMNPs) shows pH dependent release behaviour of both the drugs and enhanced toxicity towards breast cancer cell line (MCF-7) as compared to their individual treatment. Fluorescence microscopy and flow cytometric analyses confirmed the successful uptake of drug loaded system into MCF-7 cell lines. Further MTX being analogue of folic acid, its co-delivery with DOX would help in internalization of both the drugs into MCF-7 cells. These GAMNPs also show good heating efficiency under AC magnetic field (Intrinsic loss power, ILP=0.95 and 0.73 and 0.48 nHm2/Kg at Fe concentration of 0.5, 1 and 2mg/ml, respectively) and transverse relaxivity (r2=152mM-1s-1) indicating their potential capability for hyperthermia therapy and MRI tracking. Furthermore, it has been observed that the combination of chemotherapeutic drugs and hyperthermia leads to an enhancement of cytotoxicity in MCF-7 cells.

Acceleration of interstitial lung disease induced by raltitrexed

Raltitrexed is a folate analogue, which selectively inhibits thymidylate synthase, used in the treatment of colorectal carcinoma. Common side effects include asthenia and gastrointestinal and haematological toxicities. We present the case of a 74-year-old gentleman with incidental mild interstitial lung disease on preoperative staging CT Chest who developed acute breathlessness whilst undergoing adjuvant raltitrexed treatment for a completely excised colorectal adenocarcinoma. Discontinuation of raltitrexed and a course of steroid therapy resulted in resolution of symptoms, mirrored by an improvement in lung function tests. The clinical pattern of rapid progression with steroid response highlights the potential for significant acceleration of interstitial lung disease by raltitrexed.

LC-MS metabolomics comparisons of cancer cell and macrophage responses to methotrexate and polymer-encapsulated methotrexate

Methotrexate (MTX) is a folate analogue antimetabolite widely used for the treatment of rheumatoid arthritis and cancer. A number of studies have shown that MTX delivered via nanoparticle carriers is more potent against cancer cells than free MTX, a phenomenon attributed to higher cellular uptake of the particles compared to the saturable folate receptor pathway. In this study, a cell-based global metabolic profiling approach was applied to study the effects of MTX in both free drug form and when encapsulated in -poly(lactide-co-glycolide) (PLGA) nanoparticles on a cancer cell line, A549, and also on human-like THP-1 macrophages. The results showed that MTX loaded nanoparticles had less impact on the macrophages than free MTX, and the effects on macrophages were limited to changes in nucleotide metabolism and suppression of the tricarboxylic acid cycle, whereas free MTX also led to a drop in glycolytic activity and impairment in redox homeostasis. In contrast, MTX loaded nanoparticles showed a greater impact on A549 cells than the free drug, which was in accord with studies in other cell lines in prior literature with MTX-carrier nanoparticles.

Development and Validation of a Sensitive UHPLC-MS/MS-Based Method for the Analysis of Folylpolyglutamate Synthetase Enzymatic Activity in Peripheral Blood Mononuclear Cells: Application in Rheumatoid Arthritis and Leukemia Patients.

Folylpolyglutamate synthetase (FPGS) is a crucial enzyme in both cellular folate homeostasis and the intracellular retention of folate analogue drugs such as methotrexate (MTX), which is commonly used for the treatment of (pediatric) leukemia and the anchor drug in rheumatoid arthritis (RA) treatment. To date, assessment of FPGS catalytic activity relies on assays using radioactive substrates that are labor-intensive and require relatively large numbers of cells. Here, we describe a nonradioactive, ultra-high-performance liquid chromatography-tandem mass spectrometer (UHPLC-MS/MS)-based method allowing for sensitive and accurate measurements of FPGS activity in low cell numbers (ie, 1-2 × 10) of biological specimens, including leukemic blast cells of acute lymphoblastic leukemia patients and peripheral blood mononuclear cells of patients with RA. The UHPLC-MS/MS assay was validated with 2 CCRF-CEM human leukemia cells, one proficient and one deficient in FPGS activity. Linearity of time and protein input were tested by measuring FPGS activity at 30-180 minutes of incubation time and 10-300 mcg protein extract. In addition, FPGS enzyme kinetic parameters were assessed. The FPGS enzymatic assay showed a linear relation between FPGS activity and protein input (R ≥ 0.989) as well as incubation time (R ≥ 0.996). Moreover, the UHPLC-MS/MS method also allowed for evaluation of FPGS enzyme kinetic parameters revealing Km values for the substrates MTX and L-glutamic acid of 64 µmol/L and 2.2 mmol/L, respectively. The mean FPGS activity of acute lymphoblastic leukemia blast cells (n = 4) was 3-fold higher than that of CCRF-CEM cells and 44-fold and 88-fold higher than that of peripheral blood mononuclear cells from MTX-naive (n = 9) and MTX-treated RA patients (n = 6), respectively. Collectively, given its sensitivity with low cell numbers and avoidance of radioactive substrates, UHPLC-MS/MS-based analysis of FPGS activity may be eligible for routine therapeutic drug monitoring of MTX in RA and leukemia for therapy (non)response evaluations.

PS1096 INTERIM UPDATE FROM A MULTI‐CENTER STUDY OF PRALATREXATE IN ASIAN PATIENTS WITH RELAPSED OR REFRACTORY(R/R) PERIPHERAL T‐CELL LYMPHOMA (PTCL)

Background:Peripheral T‐cell lymphomas (PTCL) are a group of rare, aggressive and diverse lymphoproliferative disorder. When patients are in the relapsed/refractory setting, the survival is mostly less than 6 months. Pralatrexate, a folate analogue metabolic inhibitor, was the first monotherapy approved to treat R/R PTCL patients. As the subtypes difference between western and eastern countries, we would like to investigate the efficacy/safety of pralatrexate in Taiwanese patients.Aims:This single‐arm, multi‐center study aims to demonstrate the efficacy/ safety of pralatrexate in R/R PTCL patients. The patients who undergo Hematopoietic Stem Cell Transplantation (HSCT) or not after pralatrexate will be also investigated individually.Methods:Eligibility criteria included age ≧ 20 with PTCL according to the NCCN diagnosis criteria, the Revised European American Lymphoma (REAL), and WHO disease classification with the following subtypes: Peripheral T‐cell lymphoma, NOS (PTCL‐NOS), Angioimmunoblastic T‐cell lymphoma (AITL), Extranodal NK/T‐cell lymphoma, nasal type (ENKL), Enteropathy‐type T‐cell lymphoma (EATL), Hepatosplenic T‐cell lymphoma (HSTCL), Subcutaneous panniculitis‐like T‐cell lymphoma (SPTCL) and Adult T‐cell lymphoma/leukemia (human T‐cell leukemia virus [HTLV] 1+) (ATLL). Patients were documented disease progression after prior treatment. Intravenous pralatrexate was administrated weekly for 6 weeks in 7‐week cycles up to 5 cycles with concurrent vitamin B12 and folic acid. Patients who complete at least 1 cycle of pralatrexate and have at least 1 post‐treatment tumor assessment are defined as evaluable patients. The primary end point is Objective Response Rate (ORR, CR + PR). Secondary end points include Progression‐Free Survival (PFS), Duration of response (DoR) and Overall Survival (OS).Results:Twenty‐two patients were evaluable for efficacy per protocol definition. The subtype distribution included PTCL‐NOS (n = 9, 40.9%), AITL (n = 5, 22.7%), ENKL (n = 5, 22.7%), EATL (n = 1, 4.5%), SPTCL (n = 1, 4.5%) and ATLL (n = 1, 4.5%). The ORR was 54.5% with CR 18.2% (n = 4) and PR 36.3% (n = 8). When divided into 2 groups based on if patients received HSCT after pralatrexate, the ORR in HSCT group (n = 5) was 60% with CR 20% (n = 1) and PR 40% (n = 2), while ORR in non‐HSCT group (n = 17) was 53% with CR 18% (n = 3) and PR 35% (n = 6). At the time of data cut‐off, median PFS was 5 months (95% C.I. 5.51, 12.93), median DOR was 5.4 months (95% C.I. 2.64, 13.10) and OS not reached yet. It's notably that, among 5 patients that received HSCT successfully after pralatrexate, 4 patients are ENKL and the other is PTCL‐NOS. Except one who experienced disease progression after HSCT, the others still remain in response. It indicated that pralatrexate may play a beneficial role in bridging to transplantation in PTCL patients, especially in ENKL. Safety population analysis (n = 27) showed the most common TEAEs (grades 3–4) were: anemia (33%), stomatitis (26%), peripheral edema (22%), thrombocytopenia (15%) and leukopenia (11%).Summary/Conclusion:This interim update of this multi‐center study demonstrated the efficacy of pralatrexate monotherapy in R/R PTCL is 54.5%. Interestingly, most ENKL patients received HSCT after obtaining good disease control with pralatrexate. In addition, it showed tolerable safety profile. This is the first data demonstrated benefits of pralatrexate in R/R PTCL patients with intention or no intention to receive transplantation.image

Efficacy of methotrexate as anti-inflammatory and anti-proliferative drug in dermatology: Three case reports.

Methotrexate (MTX) is a folic acid analog with anti-proliferative (anti-neoplastic, cytotoxic), immunosuppressive and anti-inflammatory properties, which has been used in the treatment of various cutaneous disorders, such as psoriasis, keratoacanthoma, pityriasis rubra pilaris, atopic dermatitis, mycosis fungoides, bullous skin diseases, systemic sclerosis, morphea, lupus erythematosus, dermatomyositis and crusted scabies. Inhibition of cell proliferation is explained through its role in blocking DNA/RNA synthesis, by inhibiting dihydrofolate reductase, necessary for the production of pyrimidine and purine nucleotides. An anticancer effect can be related to α-oxoaldehyde metabolism (MTX increases methylglyoxal levels). Its anti-inflammatory property is based on the inhibition of 5-aminoimidazole-4-carboxamide ribonucleotide transformylase, thus increasing intracellular and extracellular adenosine, a purine nucleoside with anti-inflammatory effect. This drug can limit inflammation by scavenging free radicals and decreasing malondialdehyde-acetaldehyde protein-adduct production. Moreover, the anti-proliferative and anti-inflammatory effects can also be related to inhibition of the DNA methylation pathway, thus inhibiting methionine formation. The aim of the present study was to report various dermatological cases from our daily practice that demonstrate the efficacy of MTX in the treatment of cutaneous diseases, highlighting different mechanisms of action: its anti-inflammatory effect in psoriasis and its anti-proliferative, and anti-neoplastic effect in well-differentiated squamous cell carcinoma or in keratoacanthoma. Moreover, different administration pathways and doses are addressed. Assessment of the treatment plan, clinical improvement of cutaneous lesions, biologic evaluation, final aesthetic result, quality of life, as well as potential adverse effects and drug tolerance related to each case mentioned.

Reduced folate carrier-mediated methotrexate transport in human distal lung epithelial NCl-H441 cells.

We had previously found that reduced folate carrier (RFC; SLC19A1) is mainly involved in an influx of transport of methotrexate (MTX), a folate analogue, using alveolar epithelial A549 cells. Therefore, we examined MTX uptake in NCl-H441 (H441) cells, another invitro alveolar epithelial model, focusing on the localization of RFC in the present study. Transport function of RFC in H441 cells was studied using [3 H]MTX. The uptake of MTX was increased remarkably after pretreatment of the cell monolayer with ethylenediaminetetraacetic acid (EDTA) in H441 cells but not in A549 cells, indicating the contribution of the basolaterally located transporter. In addition, folic acid and thiamine monophosphate, RFC inhibitors, inhibited the uptake of MTX from the basolateral side of the H441 cells. In order to compare the function of RFC on the apical and basolateral sides of the cells, the uptake of MTX from each side was examined using a Transwell chamber. Intracellular MTX amounts from the basolateral side were found to be significantly higher than those from the apical side. These findings suggest that the distribution of MTX in the lung alveolar epithelial cells may be mediated by basolaterally located RFC in alveolar epithelial cells.

Human trisomy 21 fibroblasts rescue methotrexate toxic effect after treatment with 5-methyl-tetrahydrofolate and 5-formyl-tetrahydrofolate.

Trisomy 21 causes Down syndrome (DS), the most common human genetic disorder and the leading genetic cause of intellectual disability. The alteration of one-carbon metabolism was described as the possible metabolic cause of the intellectual disability development in subjects with DS. One of the biochemical pathways involved in the one-carbon group transfer is the folate cycle. The cytotoxic drug methotrexate (MTX) is a folic acid (FA) analogue which inhibits the activity of dihydrofolate reductase enzyme involved in the one-carbon metabolic cycle. Trisomy 21 cells are more sensitive to the MTX effect than euploid cells, and in 1986 Jérôme Lejeune and Coll. demonstrated that MTX was twice as toxic in trisomy 21 lymphocytes than in control cells. In the present work, the rescue effect on MTX toxicity mediated by FA and some of its derivatives, tetrahydrofolate (THF), 5-formyl-THF, and 5-methyl-THF, in both normal and trisomy 21 skin fibroblast cells, was evaluated. A statistically significant rescue effect was obtained by 5-formyl-THF, 5-methyl-THF, and their combination, administered together with MTX. In conclusion, trisomy 21 fibroblast cell lines showed a good response to the rescue effects of 5-formyl-THF and 5-methyl-THF on the MTX toxicity almost as normal cell lines.

Association of C35T polymorphism in dihydrofolate reductase gene with toxicity of methotrexate in rheumatoid arthritis patients

ABSTRACTBackground: Methotrexate (MTX), a folate analogue, is the most commonly used disease-modifying drug in the treatment of rheumatoid arthritis (RA). However, high interindividual differences in drug response are present among RA patients.Research design and methods: In a group of 234 RA patients treated with MTX, we investigated whether rs1650697 polymorphism in DHFR gene may have an impact on MTX efficacy and/or adverse drug effects (ADEs). Relative DAS28 values (rDAS28) were used for the estimation of MTX therapy and all ADEs were recorded. Patients were genotyped for selected polymorphism by real-time PCR method.Results: According to the European League Against Rheumatism criteria after 6 months of MTX therapy, 196 patients (83.8%) were classified as responders (25 (10.7%) were good and 171 (73.1%) were moderate) and 38 patients (16.2%) as nonresponders. ADEs were observed in 55 patients (23.5%).Conclusions: Our results showed that the presence of T allele might be protective against MTX hepatotoxicity measured by transaminase levels (p = 0.05). Furthermore, among patients who also received low-dose corticosteroids, we have found a lower rDAS value in patients with CC genotype (p = 0.039).

Folate Receptor Near-Infrared Optical Imaging Provides Sensitive and Specific Intraoperative Visualization of Nonfunctional Pituitary Adenomas.

Surgical resection is the primary treatment for nonfunctional (NF) pituitary adenomas, but gross-total resection is difficult to achieve in all cases. NF adenomas overexpress folate receptor alpha (FRα). To test the hypothesis that we could target FRα for highly sensitive and specific intraoperative detection of NF adenomas using near-infrared (NIR) imaging. Fourteen patients with NF pituitary adenoma were infused with the folate analog NIR dye OTL38 preoperatively. NIR fluorescence signal-to-background ratio (SBR) was recorded for each tumor during resection of the adenomas. Extent of surgery was not modified based on the presence or absence of fluorescence. Immunohistochemistry was performed to assess FRα expression in all specimens. Magnetic resonance imaging (MRI) was performed postoperatively to assess residual neoplasm. Nine adenomas overexpressed FRα and fluoresced with a NIR SBR of 3.2±0.52, whereas the 5 non-FRα-overexpressing adenomas fluoresced with an SBR of 1.5±0.21. Linear regression demonstrated a significant correlation between intraoperative SBR and the FRα expression (P-value<.001). Analysis of 14 margin samples revealed that the surgeon's impression of the tissue had 83% sensitivity, 100% specificity, 100% positive predictive value, and 89% negative predictive value, while NIR fluorescence had 100% for all values. NIR fluorescence accurately predicted postoperative MRI results in 78% of FRα-overexpressing patients. Preoperative injection of folate-tagged NIR dye provides strong signal and visualization of NF pituitary adenomas. It is 100% sensitive and specific for detecting margin neoplasm and can predict postoperative MRI findings. Our results suggest that NIR fluorescence may be superior to white-light visualization alone and may improve resection rates in NF pituitary adenomas.

Folate Enrichment of &amp;lt;i&amp;gt;Ogi&amp;lt;/i&amp;gt; (a Fermented Cereal Gruel) Using Folate Producing Starter Cultures

This study was aimed at selecting starter cultures for bio-enriching ogi (fermented cereal gruel) using folate-producing microorganisms. The folate-producing microorganisms were isolated by incorporating folate analogue, methotrexate in the isolation medium and further screened for folate production by growth in Folic Acid Casei Medium. Folate production was quantified using 3-aminophenol spectrophotometric method. Folate-producing lactic acid bacteria from fermenting maize slurry were species of Lactobacillus, Lactococcus, Pediococcus and Leuconostoc while yeast isolates were mainly species of Candida and Saccharomyces. However, Lactobacillus plantarum X13, Pediococcus pentosaceus L73, Candida parapsilosis Y77 and Candida tropicalis Y74 were used as starter cultures singly and in combination for the fermentation and production of ogi. The highest folate concentration, 30.97 ± 0.37 μg/ml, was observed after 24 h of the co-fermentation of maize slurry with Lactobacillus plantarum X13 and Candida tropicalis Y74. This represents a triple fold of the folate concentration observed in unfermented maize slurry. The pH of the fermenting maize slurry was observed to decrease from 6.12 to 3.60, while the reducing sugars and the titratable acidities were observed to increase as fermentation progressed. Sensory evaluation of the ogi samples after fermentation showed high general acceptability comparable to the naturally fermented ogi as regards to colour, taste, flavour, aroma and texture. The data made available in this study suggest the possibility of folate enrichment of ogi and its use as a vehicle for increasing folate availability to consumers thereby preventing folate deficiency diseases prevalent in many African countries.

Pharmacogenomics of Methotrexate: Current Status and Future Outlook.

Methotrexate (MTX) is a folate analogue with high therapeutic efficiency in the treatment of cancers and autoimmune diseases. The efficacy and toxicity of MTX may be altered by genetic polymorphisms in genes involved in MTX metabolic pathway. Personalized pharmacotherapy based on gene polymorphisms enables a more efficient, compatible and cost-effective treatment of patients. The present article aims to review genetic polymorphisms associated with MTX pharmacokinetics, toxicity, and outcome, and points out future development directions of individualized MTX therapy. Details regarding the pharmacogenetics and pharmacogenomics of MTX are obtained from PubMed literatures. The influences of single nucleotide polymorphisms (SNPs) in genes involved in MTX pathway are controversial. Many pharmacogenetic associations are disease specific and race specific. Present studies have almost limited to some certain ethnic groups and diseases. The data from these studies are not convincing enough to draw far-reaching conclusions about the applicability of MTX pharmacogenetics in clinical practice. Studies with large scale and multiple centers are needed in the future. MTX-PG inhibits folic metabolism through three mechanisms. TS, MTHFR and ATIC are the rate-limiting enzymes separately. The function of SNPs in these genes is often onesided. Works focusing on the analysis of polymorphism in MTX transporters should be more efficient and meaningful.

Modulation of Redox Homeostasis by Inhibition of MTHFD2 in Colorectal Cancer: Mechanisms and Therapeutic Implications.

BackgroundOvercoming oxidative stress is a critical step for tumor progression; however, the underlying mechanisms in colorectal cancer (CRC) remain unclear.MethodsWe investigated nicotinamide adenine dinucleotide (phosphate) (NAD(P))-dependent enzyme methylene tetrahydrofolate dehydrogenase 2 (MTHFD2) expression, clinical relevance, redox modification, and molecular mechanisms using the CRC cells and tissues (n = 462 paired samples). The antitumor effects of MTHFD2 inhibitor LY345899 on CRC tumorigenesis and metastasis were evaluated in vitro and in vivo. Data analysis used Kaplan-Meier, Pearson’s correlation, and Student t test where appropriate. All statistical tests were two-sided.ResultsHere, we report that the patients with high expression of MTHFD2 have a shorter overall survival (HR = 1.62, 95% CI = 1.12 to 2.36, P = .01) and disease-free survival (HR = 1.55, 95% CI = 1.07 to 2.27, P = .02) than patients with low MTHFD2 expression. Suppression of MTHFD2 disturbs NADPH and redox homeostasis and accelerates cell death under oxidative stress, such as hypoxia or anchorage independence (P ≤ .01 for all). Also, genetic or pharmacological inhibition of MTHFD2 suppresses CRC cell growth and lung and peritoneal metastasis in cell-based xenografts (n = 5–8 mice per group). Importantly, LY345899 treatment statistically significantly suppresses tumor growth and decreases the tumor weight in CRC patient-derived xenograft models (n = 10 mice per group, mean [SD] tumor weight of the vehicle-treated group was 1.83 [0.19] mg vs 0.74 [0.30] mg for the LY345899-treated group, P < .001)ConclusionsOur study presents evidence that MTHFD2 confers redox homeostasis and promotes CRC cell growth and metastasis. The folate analog LY345899 as MTHFD2 inhibitor displays therapeutic activity against CRC and warrants further clinical investigation for CRC treatment.

Evaluation of methotrexate-conjugated gadolinium(III) for cancer diagnosis and treatment

BackgroundGliomas are one of the most common types of primary brain tumors. It is usually evaluated by gadolinium(III)-based contrast agents by magnetic resonance imaging (MRI) in the clinic. Methotrexate (MTX), as a type of folate analog that inhibits the enzyme dihydrofolate reductase, is widely used as a chemotherapeutic agent to treat gliomas in the experiment.PurposeIn this study, a novel theranostic agent MTX-DOTA-Gd (MTX-Gd) was synthesized, which integrates magnetic resonance imaging (MRI) with anticancer treatment.MethodsMTX-Gd was synthesized by connecting MTX and Gd through 1,4,7,10-tetraazacy-clododecane-1,4,7,10-tetraacetic acid (DOTA). The characterization of MTX-Gd was detected by ultraviolet (UV) and infrared spectroscopy (IR). To confirm the antitumor effect of MTX-Gd, the cytotoxicity of MTX-Gd was examined by the MTT assay. The contrast enhancement of the MTX-Gd was measured through MRI in vitro. Then, nude mice bearing C6 tumor xenografts were used to study in vivo imaging capabilities.ResultsThe ultraviolet-visible-near infrared radiation (UV-NIR) absorption curve indicated that MTX-Gd had a broad absorption in the region of 500-700 nm. The formation of MTX-Gd was confirmed from the characteristic bands of MTX-DOTA-Gd in the 1413 cm−1 (C-N), 1577 cm−1 (−NH2), and 3429 cm−1 (N-H), in the fourier-transform infrared (FTIR) spectra. MTX-Gd showed little difference in the cell viability compared with MTX, except for the highest concentration (270 μM). In vitro, the imaging of MTX-Gd was significantly brighter than Gd-DOTA at the same concentration, and the brightness and signal intensity of MRI were increased followed by the increased concentration of MTX-Gd. And it also showed that MTX was not visualized on MRI. The other images revealed that the concentration of 4 mM MTX-Gd had the same imaging effect with the concentration of 10 mM Gd-DOTA. Then, MTX-Gd was injected in nude mice bearing C6 tumor xenografts through the tail vein. Significant contrast enhancement was observed at the tumor site from 0.5 h to 3 h. The signal of tumor area was strongest at 3 h due to accumulation by size effect of macromolecules.ConclusionA novel stable and unique theranostic agent (MTX-Gd) was successfully synthe-sized, and it has good stability, strong anticancer ability and excellent magnetic capacity. The methotrexate component of MTX-Gd, as a chemotherapeutic agent, played an important role in targeted therapies of cancer. The DOTA-Gd component of MTX-Gd performed as the MRI contrast agent. The superior MRI imaging performance and synergetic chemical antineoplastic ability of MTX-Gd was revealed, and it has great potential in the diagnosis and treatment of glioma and potentially other cancers, with prospects of clinical application in the near future.

Genetic markers in methotrexate treatments.

Methotrexate (MTX), a structural analog of folic acid, is widely employed in the treatment of different cancers and autoimmune diseases. Despite the successful results observed, the main disadvantage lies in interpatient variability in the pharmacokinetic and pharmacodynamic parameters. In particular, adverse events and toxicities induced by MTX are a matter of concern and can be the cause of dose reduction or treatment discontinuation. Among the different approaches to reduce MTX therapeutic limitations, pharmacogenomics contributes by considering the effect of inherited genetic differences on those parameters. This review provides an update on MTX pharmacogenomics. It reports the contribution of main gene polymorphisms involved in the influx, efflux, cellular effect, and elimination on MTX toxicity and efficacy, on all the diseases treated with this drug. From the analysis of the data presented in this review, we concluded that only gene polymorphisms MTHFR rs1801133, SLC19A1 rs1051266, and TYMS rs34743033 could influence clinical decision-making.

Mitochondrial dysfunction and oxidative stress are involved in the mechanism of methotrexate-induced renal injury and electrolytes imbalance

Methotrexate is a folate analog used against a wide range of diseases including malignancies and autoimmune disorders. On the other hand, clinical use of the MTX is associated with kidney injury and renal failure. There is no clear mechanism for MTX-induced renal injury. The current investigation was designed to evaluate the role of mitochondrial dysfunction and oxidative stress in the pathogenesis of MTX-induced renal injury. Rats received MTX (a single dose of 20 or 30 mg/kg, i.p). Five days after MTX administration, serum biomarkers of kidney injury and tissue markers of oxidative stress were assessed. Moreover, kidney mitochondria were isolated, and several mitochondrial indices were determined. MTX-treated animals developed biochemical evidence of renal injury as judged by elevated serum blood urea nitrogen (BUN), creatinine (Cr) and along with hypokalemia, hypophosphatemia, hypocalcemia, and a decrease in serum glucose, and uric acid. Moreover, MTX caused an increase in kidney reactive oxygen species and lipid peroxidation. Renal glutathione reservoirs were also depleted, and tissue antioxidant capacity was decreased in MTX-treated animals. Kidney histopathological changes including interstitial inflammation, renal tubular degeneration, retraction glomeruli, and vascular congestion were also evident in MTX-treated rats. On the other hand, it was found that mitochondrial parameters including mitochondrial membrane potential, mitochondrial dehydrogenases activity, and mitochondrial glutathione and ATP content were decreased, while lipid peroxidation and mitochondrial permeabilization were increased with MTX treatment. These data suggest a role for mitochondrial dysfunction and oxidative stress in the mechanism of MTX nephrotoxicity.

Nucleoside Analogue-Based Supramolecular Nanodrugs Driven by Molecular Recognition for Synergistic Cancer Therapy.

The utilization of nanotechnology for the delivery of a wide range of anticancer drugs has the potential to reduce adverse effects of free drugs and improve the anticancer efficacy. However, carrier materials and/or chemical modifications associated with drug delivery make it difficult for nanodrugs to achieve clinical translation and final Food and Drug Administration (FDA) approvals. We have discovered a molecular recognition strategy to directly assemble two FDA-approved small-molecule hydrophobic and hydrophilic anticancer drugs into well-defined, stable nanostructures with high and quantitative drug loading. Molecular dynamics simulations demonstrate that purine nucleoside analogue clofarabine and folate analogue raltitrexed can self-assemble into stable nanoparticles through molecular recognition. In vitro studies exemplify how the clofarabine:raltitrexed nanoparticles could greatly improve synergistic combination effects by arresting more G1 phase of the cell cycle and reducing intracellular deoxynucleotide pools. More importantly, the nanodrugs increase the blood retention half-life of the free drugs, improve accumulation of drugs in tumor sites, and promote the synergistic tumor suppression property in vivo.