Pemetrexed: a multitargeted antifolate

Advancing perspectives on the off-label use of anticancer drugs: an updated classification and exploration of categories

To date, the definition that the off-label usage of drugs refers to the unapproved use of approved drugs, which covers unapproved indications, patient populations, doses, and/or routes of administration, has been in existence for many years. Currently, there is a limited frequency and prevalence of research on the off-label use of antineoplastic drugs, mainly due to incomplete definition and classification issues. It is time to embrace new categories for the off-label usage of anticancer drugs. This review provided an insight into an updated overview of the concept and categories of the off-label use of anticancer drugs, along with illustrating specific examples to establish the next studies about the extent of the off-label usage of anticancer drugs in the oncology setting. The scope of the off-label use of current anticancer drugs beyond the previous definitions not only includes off-label uses in terms of indications, patient populations, doses, and/or routes of administration but also off-label use in terms of medication course, combination, sequence of medication, clinical purpose, contraindications scenarios, etc. In addition, the definition of the off-label usage of anticancer drugs should be added to the condition at a given time, and it varies from approval authorities. We presented a new and relatively comprehensive classification, providing extensive analysis and illustrative examples of the off-label usage of antineoplastic drugs for the first time. Such a classification has the potential to promote practical adoption and enhance management strategies for the off-label use of antitumor drugs.

Double-dose osimertinib combined with intrathecal injection of pemetrexed improves the efficacy of EGFR-mutant non-small cell lung cancer and leptomeningeal metastasis: case report and literature review

Leptomeningeal metastasis (LM) is a complication of non-small cell lung cancer (NSCLC) characterized by poor prognosis and short survival. A variety of therapeutic approaches have been sought to improve the efficacy of LM. Here we present a clinical case and conduct a literature review to investigate the effectiveness and safety of double-dose osimertinib combined with a pemetrexed intrathecal injection. This is an older man who underwent thoracoscopic pneumonectomy and was diagnosed with stage IIA lung adenocarcinoma with EGFR21 L858R mutation. He experienced thoracic vertebral metastases 33 months postoperatively and received first-line treatment with gefitinib combined with radiotherapy for vertebral metastases. However, the patient developed a grade 3 rash with unacceptable toxicity and his CEA levels were significantly increased 22 months later, leading to a targeted treatment adjustment to 80 mg of osimertinib orally once daily. Four months later, the patient developed LM and osimertinib dosage was increased to 160 mg once daily; however, neurological symptoms did not improve, and cerebrospinal fluid (CSF) tumor cells remained detected. Accordingly, the patient received an intrathecal injection of pemetrexed (dose 30 mg) every 2-3 months, 2-3 times per course (4-6 days each time), and continued to receive a double dose of osimertinib. After three courses of intrathecal chemotherapy, CSF tumor cells were eliminated, and neurological symptoms significantly improved. During the treatment, he experienced a one-degree rash, leukopenia, thrombocytopenia, and fatigue. This patient has been alive and well with disease control for 28 months since the diagnosis of meningeal metastases. Combining double-dose osimertinib and an intrathecal injection of pemetrexed demonstrated therapeutic efficacy and manageable adverse effects in this patient with advanced NSCLC with EGFR-mutant and LM.

Dual-Target Mycobacterium tuberculosis Inhibition: Insights into the Molecular Mechanism of Antifolate Drugs

The escalating prevalence of drug-resistant strains of Mycobacterium tuberculosis has posed a significant challenge to global efforts in combating tuberculosis. To address this issue, innovative therapeutic strategies are required that target essential biochemical pathways while minimizing the potential for resistance development. The concept of dual targeting has gained prominence in drug discovery against resistance bacteria. Dual targeting recognizes the complexity of cellular processes and disrupts more than one vital pathway, simultaneously. By inhibiting more than one essential process required for bacterial growth and survival, the chances of developing resistance are substantially reduced. A previously reported study investigated the dual-targeting potential of a series of novel compounds against the folate pathway in Mycobacterium tuberculosis. Expanding on this study, we investigated the predictive pharmacokinetic profiling and the structural mechanism of inhibition of UCP1172, UCP1175, and UCP1063 on key enzymes, dihydrofolate reductase (DHFR) and 5-amino-6-ribitylamino-2,4(1H,3H)-pyrimidinedione 5'-phosphate reductase (RV2671), involved in the folate pathway. Our findings indicate that the compounds demonstrate lipophilic physiochemical properties that promote gastrointestinal absorption, and may also inhibit the drug-metabolizing enzyme, cytochrome P450 3A4, thus enhancing their biological half-life. Furthermore, key catalytic residues (Serine, Threonine, and Aspartate), conserved in both enzymes, were found to participate in vital molecular interactions with UCP1172, which demonstrated the most favorable free binding energies to both DHFR and RV2671 (-41.63 kcal/mol, -48.04 kcal/mol, respectively). The presence of characteristic loop shifts, which are similar in both enzymes, also indicates a common inhibitory mechanism by UCP1172. This elucidation advances the understanding of UCP1172's dual inhibition mechanism against Mycobacterium tuberculosis.

Integration of metabolomics and machine learning revealed tryptophan metabolites are sensitive biomarkers of pemetrexed efficacy in non-small cell lung cancer

BACKGROUND

Anti-folate drug pemetrexed is a vital chemotherapy medication for non-small cell lung cancer (NSCLC). Its response varies widely and often develops resistance to the treatment. Therefore, it is urgent to identify biomarkers and establish models for drug efficacy evaluation and prediction for rational drug use.

METHODS

A total of 360 subjects were screened and 323 subjects were recruited. Using metabolomics in combination with machine learning methods, we are trying to select potential biomarkers to diagnose NSCLC and evaluate the efficacy of pemetrexed in treating NSCLC. Furtherly, we measured the concentration of eight metabolites in the tryptophan metabolism pathway in the validation set containing 201 subjects using a targeted metabolomics method with UPLC-MS/MS.

RESULTS

In the discovery set containing 122 subjects, the metabolic profile of healthy controls (H), newly diagnosed NSCLC patients (ND), patients who responded well to pemetrexed treatment (S) and pemetrexed-resistant patients (R) differed significantly on the PLS-DA scores plot. Pathway analysis showed that glycine, serine and threonine metabolism occurred in every two group comparisons. TCA cycle, pyruvate metabolism and glycerolipid metabolism are the most significantly changed pathways between ND and H group, pyruvate metabolism was the most altered pathway between S and ND group, and tryptophan metabolism was the most changed pathway between S and R group. We found Random forest method had the maximum area under the curve (AUC) and can be easily interpreted. The AUC is 0.981 for diagnosing patients with NSCLC and 0.954 for evaluating pemetrexed efficiency.

CONCLUSION

We compared eight mathematical models to evaluate pemetrexed efficiency for treating NSCLC. The Random forest model established with metabolic markers tryptophan, kynurenine and xanthurenic acidcan accurately diagnose NSCLC and evaluate the response of pemetrexed.

A Subset of Non-Small Cell Lung Cancer Patients Treated with Pemetrexed Show 18F-Fluorothymidine "Flare" on Positron Emission Tomography

Thymidylate synthase (TS) remains a major target for cancer therapy. TS inhibition elicits increases in DNA salvage pathway activity, detected as a transient compensatory "flare" in 3'-deoxy-3'-[18F]fluorothymidine positron emission tomography (18F-FLT PET). We determined the magnitude of the 18F-FLT flare in non-small cell lung cancer (NSCLC) patients treated with the antifolate pemetrexed in relation to clinical outcome.

METHOD

Twenty-one patients with advanced/metastatic non-small cell lung cancer (NSCLC) scheduled to receive palliative pemetrexed ± platinum-based chemotherapy underwent 18F-FLT PET at baseline and 4 h after initiating single-agent pemetrexed. Plasma deoxyuridine (dUrd) levels and thymidine kinase 1 (TK1) activity were measured before each scan. Patients were then treated with the combination therapy. The 18F-FLT PET variables were compared to RECIST 1.1 and overall survival (OS).

RESULTS

Nineteen patients had evaluable PET scans at both time points. A total of 32% (6/19) of patients showed 18F-FLT flares (>20% change in SUVmax-wsum). At the lesion level, only one patient had an FLT flare in all the lesions above (test-retest borders). The remaining had varied uptake. An 18F-FLT flare occurred in all lesions in 1 patient, while another patient had an 18F-FLT reduction in all lesions; 17 patients showed varied lesion uptake. All patients showed global TS inhibition reflected in plasma dUrd levels (p < 0.001) and 18F-FLT flares of TS-responsive normal tissues including small bowel and bone marrow (p = 0.004 each). Notably, 83% (5/6) of patients who exhibited 18F-FLT flares were also RECIST responders with a median OS of 31 m, unlike patients who did not exhibit 18F-FLT flares (15 m). Baseline plasma TK1 was prognostic of survival but its activity remained unchanged following treatment.

CONCLUSIONS

The better radiological response and longer survival observed in patients with an 18F-FLT flare suggest the efficacy of the tracer as an indicator of the early therapeutic response to pemetrexed in NSCLC.

Ocular adverse effects of anti-cancer chemotherapy

Cancer ranks as the second leading cause of mortality in Europe, following cardiovascular diseases. Every year, 2.6 million people are diagnosed with this disease, and 1.2 million die. It has an impact not only on individual health but also on society and the economy. The survival rate has improved with the introduction of new diagnostic methods and anti-cancer chemotherapy. While more aggressive chemotherapeutic regimens and combination therapies have demonstrated efficacy against cancer cells, they also have detrimental effects on normal cells, leading to systemic and ocular adverse reactions associated with cytotoxicity, inflammation, and neurotoxicity. Consequently, we have an increased survival rate, but the appearance of these ocular adverse effects decreases the quality of life. Ocular toxicity induced by chemotherapeutic agents is often underestimated. While prevention may not be possible, proper management by an ophthalmologist, an integral part of the oncology patient's medical team, is crucial. The ophthalmologist should assess the patient before initiating chemotherapeutic treatment and continue monitoring throughout to identify any adverse ocular reactions resulting from the systemic chemotherapy. This article aimed to briefly highlight the adverse reactions occurring at the ocular surface in patients undergoing chemotherapeutic treatment. Fortunately, these ocular side effects are limited only to the period in which the chemotherapeutic treatment is done, with most of them disappearing a few weeks after stopping the treatment.

Stability of pemetrexed disodium in sodium chloride 0.9% w/v intravenous Viaflo infusion bags

OBJECTIVES

The aim of this study was to assess the stability of pemetrexed disodium (Alimta), reconstituted in 100 mL sodium chloride 0.9% w/v intravenous infusion bags (Baxter Viaflo) at two target bag concentrations (2.0 and 13.5 mg/mL) during storage at 2-8°C for 28 days (protected from light), followed by 24 hours at 25±2°C with 60±5% relative humidity (RH) (protected from light). This study was commissioned by NHS England and NHS Improvement to generate data to aid shelf life extensions for aseptic products compounded in National Health Service (NHS) hospital aseptic facilities.

METHODS

A high performance liquid chromatography (HPLC) assay was developed and validated to monitor pemetrexed concentration and related substance levels in accordance with NHS yellow cover document requirements. This assay and analysis of related substances was used alongside visual inspection, pH monitoring and sub-visible particle count analysis to monitor stability. The stability of three preparations of each concentration of pemetrexed disodium in Viaflo saline bags (0.9% w/v) was assessed at various time points.

RESULTS

Pemetrexed assay concentrations remained >97.0% of initial concentration at all points during the study (including the period at elevated temperature). Appearance remained consistent with the Summary of Product Characteristics, particle count data remained within the British Pharmacopoeia limits, and pH remained within 0.43 units of T=0 at all times. The increases in related substance levels during the study were found to be the limiting factor for shelf life assignment.

CONCLUSION

The data for appearance, pH, sub-visible particle count analysis and pemetrexed assay would support a shelf life of 28 days stored at 2-8°C (protected from light) followed by 24 hours at 25±2°C with 60±5% RH (protected from light). However, given the increase in related substance levels, a shelf life of 21 days stored at 2-8°C (protected from light) was deemed to be appropriate.

Bench-to-Bedside Studies of Arginine Deprivation in Cancer

Arginine is a semi-essential amino acid which becomes wholly essential in many cancers commonly due to the functional loss of Argininosuccinate Synthetase 1 (ASS1). As arginine is vital for a plethora of cellular processes, its deprivation provides a rationale strategy for combatting arginine-dependent cancers. Here we have focused on pegylated arginine deiminase (ADI-PEG20, pegargiminase)-mediated arginine deprivation therapy from preclinical through to clinical investigation, from monotherapy to combinations with other anticancer therapeutics. The translation of ADI-PEG20 from the first in vitro studies to the first positive phase 3 trial of arginine depletion in cancer is highlighted. Finally, this review discusses how the identification of biomarkers that may denote enhanced sensitivity to ADI-PEG20 beyond ASS1 may be realized in future clinical practice, thus personalising arginine deprivation therapy for patients with cancer.

Study on co-delivery of pemetrexed disodium and Bcl-2 siRNA by poly-γ-glutamic acid-modified cationic liposomes for the inhibition of NSCLC

Due to the complexity of the pathophysiology of non-small cell lung cancer (NSCLC) and the susceptibility of single chemotherapy to drug resistance, the combination of drugs and small interfering RNA (siRNA) may produce a desired therapeutic effect on NSCLC through the action of multiple pathways. We designed to develop poly-γ-glutamic acid-modified cationic liposomes (γ-PGA-CL) to co-deliver pemetrexed disodium (PMX) and siRNA to treat NSCLC. Firstly, γ-PGA was modified on the surface of PMX and siRNA co-loaded cationic liposomes by electrostatic interaction (γ-PGA modified PMX/siRNA-CL). In order to evaluate whether the prepared γ-PGA modified PMX/siRNA-CL could be taken up by tumor cells and exert significant anti-tumor effects, in vitro and in vivo studies were performed, with A549 cells and LLC-bearing BABL/c mice as experimental models, respectively. The particle size and zeta potential of γ-PGA modified PMX/siRNA-CL was (222.07 ± 1.23) nm and (-11.38 ± 1.44) mV. A preliminary stability experiment showed the complex could protect siRNA from degradation. In vitro cell uptake experiment indicated the complex group exerted stronger fluorescence intensity and expressed higher flow detection value. Cytotoxicity study showed the cell survival rate of γ-PGA-CL was (74.68 ± 0.94)%. Polymerase chain reaction (PCR) analysis and western blot technology displayed that the complex could inhibit the expression of Bcl-2 mRNA and protein to promote cell apoptosis. In vivo anti-tumor experiments represented the complex group showed a significant inhibitory effect on tumor growth, while the vector showed no obvious toxicity. Therefore, the current studies proved the feasibility of combining PMX and siRNA by γ-PGA-CL as a potential strategy for the treatment of NSCLC.

Pyrrole-based EGFR inhibitors for the treatment of NCSLC: Binding modes and SARs investigations

The treatment of advanced non-small cell lung cancer (NSCLC) has made substantial progress due to the rapid development of small molecule targeted therapy, with dramatically prolonged survival. As an effective drug for the treatment of NSCLC, epidermal growth factor receptor (EGFR) inhibitors are currently experiencing issues like severe adverse events and drug resistance. It is urgent to develop novel types of EGFR inhibitors to overcome the abovementioned limitations. Pyrrole always works well as a probe for the creation of novel medication candidates for hard-to-treat conditions like lung cancer. Although the design, synthesis, and biological assays of pyrrole derivatives have been reported, their inhibitory actions against the receptor tyrosine kinase (RTK) EGFR have not been in-depthly studied. This review highlights the small molecule EGFR inhibitors containing pyrrole heterocyclic pharmacophores in recent years, and the research on their mechanism, biological activity, and structure-activity relationship (SAR).

Towards establishment of a plant-based model to assess the novel anti-cancerous lead molecule(s): An in silico, in vivo and in vitro assessment of some potential anti-cancerous drugs on Lathyrus sativus L

The drug development process is one of the important aspects of medical biology. The classical lead identification strategy in the way of drug development based on animal cell is time-consuming, expensive and involving ethical issues. The following study aims to develop a novel plant-based screening of drugs. Study shows the efficacy of certain anti-cancerous drugs (Pemetrexed, 5-Fluorouracil, Methotrexate, Topotecan and Etoposide) on a plant-based (Lathyrus sativus L.) system. Two important characteristics of cancer cells were observed in the colchicine-treated polyploid cell and the callus, where the chromosome numbers were unusual and the division of cells were uncontrolled respectively. With increasing concentration, the drugs significantly reduced the mitotic index, ploidy level and callus growth. Increasing Pemetrexed concentration decreased the plant DHFR activity. A decrease in total RNA content was observed in 5-FU and Methotrexate with increasing concentrations of the drugs. Etoposide and Topotecan inhibited plant topoisomerase II and topoisomerase I activities, which was justified through plasmid nicking and comet assay, respectively. Molecular and biochemical study revealed similar results to the animal system. The in silico study had been done, and the structural similarity of drug binding domains of L. sativus and human beings had also been established. The binding site of the selected drugs to the domains of plant target proteins was also determined. Experimental results are significant in terms of the efficacy of known anti-cancerous drugs on the plant-based system. The proposed assay system is a cost-effective, convenient and less time-consuming process for primary screening of anti-cancerous lead molecules.

Pharmacokinetics, bioavailability, and plasma protein binding study of glytrexate, a novel multitarget antifolate

Glytrexate, developed by our team, as a novel multitarget folate antagonist, has inhibitory effects on a variety of cancer cell types, especially KB tumor cells (IC₅₀ 0.078 nM), and thus has antitumor drug development prospects. However, its pharmacokinetics and plasma protein binding properties remain unknown. In this study a selective and sensitive liquid chromatography-tandem mass spectrometry (LC‒MS/MS) method was developed and verified to facilitate biological analysis. The bioanalysis method was applied to evaluate the stability, plasma protein binding, and pharmacokinetics of glytrexate. Glytrexate is more stable in human plasma than in rat plasma and in human liver microsomes. The binding of glytrexate to human plasma proteins was higher than that to rat plasma proteins, both of which were less than 30%, suggesting that glytrexate may be at a higher concentration at the pharmacologic target receptor(s) in tissues. Pharmacokinetic characteristics were determined by noncompartmental analysis after administration of single oral (12.5, 25 and 50 mg/kg) and intravenous (2 mg/kg) doses in rats. According to the rat oral pharmacokinetic characteristics, glytrexate had linear dynamics in a dose range of 12.5–50 mg/kg and a poor oral bioavailability of 0.57–1.15%. The investigation revealed that the intravenous half-life, AUC, and C_max of glytrexate were higher than those of pemetrexed. Pemetrexed is generally produced as an injection preparation. This provides ideas for the development of glytrexate formulations. Therefore, glytrexate injection has clinical application prospects compared to oral administration. This study provides a basis for further investigations into the pharmacological effects and clinical uses of glytrexate.

Assessing the environmental benefit of palladium-based single-atom heterogeneous catalysts for Sonogashira coupling

The Pd-Cu catalysed Sonogashira coupling of terminal alkynes and aryl halides is a cornerstone synthetic strategy for C-C bond formation. Homogeneous organometallic systems conventionally applied are typically not reusable and require efficient downstream Pd removal steps for product purification, making it challenging to fully recover the precious metal. A holistic cradle-to-gate life cycle assessment (LCA) unveils that process footprint can be improved up to two orders of magnitude from repeated catalyst reuse. New classes of heterogeneous catalysts based on isolated metal atoms (single-atom catalysts, SACs) demonstrate promising potential to synergise the benefits of solid and molecular catalysts for efficient Pd utilisation. Here we show that using Pd atoms anchored on nitrogen-doped carbon permits full recovery of the metal and reuse of the catalyst over multiple cycles. A hybrid process using the Pd-SAC with a homogeneous CuI cocatalyst is more effective than a fully heterogeneous analogue based on a bimetallic Pd-Cu SAC, which deactivates severely due to copper leaching. In some scenarios, the LCA-based metrics demonstrate the footprint of the hybrid homogeneous-heterogeneous catalytic process is leaner than the purely homogeneous counterpart already upon single reuse. Combining LCA with experimental evaluation will be a useful guide to the implementation of solid, reusable catalysts for sustainable organic transformations.

Dermatological adverse events associated with immune checkpoint inhibitor-based combinations of anticancer therapies: a systematic review

Aim: This paper presents the reported dermatological adverse events (AEs) associated with approved combinations of immunotherapy with drugs of the same class, or in combination with targeted therapy or chemotherapy. Materials & methods: PubMed was used as an electronic database, and a total of 29 articles were reviewed which reported dermatological AEs following combination therapies with nivolumab, ipilimumab, axitinib, pembrolizumab, lenvatinib, avelumab, atezolizumab, carboplatin, etoposide, paclitaxel, bevacizumab, pemetrexed, cisplatin and durvalumab. Results: The dermatological AEs reported were mutually inclusive and the highest incidence of specific AEs was seen in the following combinations: rash in the nivolumab/ipilimumab and lenvatinib/pembrolizumab combinations, pruritus in the atezolizumab/nab-paclitaxel combination, dry skin and palmar-plantar erythrodysesthesia in the axitinib/pembrolizumab combination, and alopecia and severe skin reactions in the pembrolizumab/carboplatin/paclitaxel combination. Conclusion: Knowledge of such side effects is of benefit when choosing an optimal treatment regimen and should be integrated into the monitoring and follow-up phases of treatment.

Naturally occurring, natural product inspired and synthetic heterocyclic anti-cancer drugs

This chapter describes the importance and activity of a huge number of commercially available naturally occurring, natural product derived or synthetic heterocyclic anti-cancer drugs.

A novel oral metronomic chemotherapy provokes tumor specific immunity resulting in colon cancer eradication in combination with anti-PD-1 therapy

In this study, we investigated the immune-modulating effects of a novel metronomic chemotherapy (MCT) featuring combined oral oxaliplatin (OXA) and pemetrexed (PMX) for colon cancer. OXA and PMX were ionically complexed with lysine derivative of deoxycholic acid (DCK), and incorporated into nanoemulsions or colloidal dispersions, yielding OXA/DCK-NE and PMX/DCK-OP, respectively, to improve their oral bioavailabilities. MCT was not associated with significant lymphotoxicity whereas the maximum tolerated dose (MTD) afforded systemic immunosuppression. MCT was associated with more immunogenic cell death and tumor cell MHC-class I expression than was MTD. MCT improved the tumor antigen presentation of dendritic cells and increased the number of functional T cells in the tumor. MCT also helped to enhance antigen-specific memory responses both locally and systemically. By combining MCT with anti-programmed cell death protein-1 (αPD-1) therapy, the tumor volume was suppressed by 97.85 ± 84.88% compared to the control, resulting in a 95% complete response rate. Upon re-challenge, all tumor-free mice rejected secondary tumors, indicating the induction of a tumor specific memory response. Thus, MCT using an OXA and PMX combination, together with αPD-1, successfully treated colon cancer by activating both innate and adaptive immune cells and elicited tumor-specific long-term immune memory while avoiding toxicity caused by MTD treatment.

Chemotherapy-induced CDA expression renders resistant non-small cell lung cancer cells sensitive to 5'-deoxy-5-fluorocytidine (5'-DFCR)

BACKGROUND

Pemetrexed (MTA) plus cisplatin combination therapy is considered the standard of care for patients with advanced non-small-cell lung cancer (NSCLC). However, in advanced NSCLC, the 5-year survival rate is below 10%, mainly due to resistance to therapy. We have previously shown that the fraction of mesenchymal-like, chemotherapy-resistant paraclone cells increased after MTA and cisplatin combination therapy in the NSCLC cell line A549. Cytidine deaminase (CDA) and thymidine phosphorylase (TYMP) are key enzymes of the pyrimidine salvage pathway. 5'-deoxy-5-fluorocytidine (5'-DFCR) is a cytidine analogue (metabolite of capecitabine), which is converted by CDA and subsequently by TYMP into 5-fluorouracil, a chemotherapeutic agent frequently used to treat solid tumors. The aim of this study was to identify and exploit chemotherapy-induced metabolic adaptations to target resistant cancer cells.

METHODS

Cell viability and colony formation assays were used to quantify the efficacy of MTA and cisplatin treatment in combination with schedule-dependent addition of 5'-DFCR on growth and survival of A549 paraclone cells and NSCLC cell lines. CDA and TYMP protein expression were monitored by Western blot. Finally, flow cytometry was used to analyze the EMT phenotype, DNA damage response activation and cell cycle distribution over time after treatment. CDA expression was measured by immunohistochemistry in tumor tissues of patients before and after neoadjuvant chemotherapy.

RESULTS

We performed a small-scale screen of mitochondrial metabolism inhibitors, which revealed that 5'-DFCR selectively targets chemotherapy-resistant A549 paraclone cells characterized by high CDA and TYMP expression. In the cell line A549, CDA and TYMP expression was further increased by chemotherapy in a time-dependent manner, which was also observed in the KRAS-addicted NSCLC cell lines H358 and H411. The addition of 5'-DFCR on the second day after MTA and cisplatin combination therapy was the most efficient treatment to eradicate chemotherapy-resistant NSCLC cells. Moreover, recovery from treatment-induced DNA damage was delayed and accompanied by senescence induction and acquisition of a hybrid-EMT phenotype. In a subset of patient tumors, CDA expression was also increased after treatment with neoadjuvant chemotherapy.

CONCLUSIONS

Chemotherapy increases CDA and TYMP expression thereby rendering resistant lung cancer cells susceptible to subsequent 5'-DFCR treatment.

Antiaging gene Klotho regulates epithelial-mesenchymal transition and increases sensitivity to pemetrexed by inducing lipocalin-2 expression

Epithelial-mesenchymal transition (EMT) is considered to serve an important role in the metastatic/invasive ability of cancer cells, in the acquisition of drug resistance, and in metabolic reprogramming. In the present study, it was hypothesized that the Klotho gene is involved in the metastatic/invasive ability of lung cancer. We previously reported an association between Klotho expression and overall survival in patients with small cell lung cancer and large cell neuroendocrine cancer. We also found that Klotho expression was associated with EMT-related molecules in lung squamous cell carcinoma. The present study aimed to analyze the function of the Klotho gene and to elucidate its relevance to the regulation of the EMT. For this purpose, GFP-Klotho plasmids were transfected into lung adenocarcinoma cells (A549) and cell lines with stable expression (A549/KL-1 and A549/KL-2) were established. A549/KL-1 cells expressed higher levels of Klotho protein by western blot analysis compared with A549/KL-2 cells. In western blotting of A549 and A549/KL-1 cells, the expression of the mesenchymal marker N-cadherin was found to be completely inhibited in A549/KL-1 cells suggesting that Klotho expression may regulate the EMT in cancer cells via the inhibition of N-cadherin. The results of the sensitivity tests demonstrated that A549/KL-1 cells were significantly more sensitive to pemetrexed compared with A549 cells (IC₅₀ A549/KL-1 vs. A549 cells, 0.1 µM vs. 0.7 µM). The results of the microarray analysis demonstrated that a very high level of lipocalin-2 (LCN2) expression was induced in the A549/KL-1 cells. Klotho overexpression completely suppressed the expression of mesenchymal markers, such as N-cadherin and Snail1 (Snail). The results of the present study suggested that there may be a new mechanism of action for the antitumor effects of pemetrexed, namely, LCN2-mediated modulation of N-cadherin expression. Klotho expression during cancer treatment has great potential as a predictor for efficacy of pemetrexed and as a factor in the selection of personalized medicine for postoperative adjuvant chemotherapy.

The Challenging Management of Cancer: An Immunonephrologist's Perspective

INTRODUCTION

Onconephrology is an emerging medical subspecialization that focuses on the numberless interrelations between cancer and kidney diseases. Tumor cells evade immune surveillance through activation of immune checkpoint pathways that suppress antitumor immune responses. By blocking checkpoints, new anticancer agents disrupt immune homeostasis but potentially induce immune-mediated diseases. Nephrologists and nephroimmunologists should be able to treat the nephrotoxic sequelae of cancer therapy and ensure continuation of the life-saving treatment.

METHODS

Thirty-seven renal biopsies have been carried out over 42 months in oncologic patients, that is, 5.2% of the total native renal biopsies were carried out in the same period. The commonest diagnoses (>6 cases) were interstitial tubular nephritis, membranous glomerulopathy, IgA nephropathy, vasculitis, and focal and segmental glomerulosclerosis.

CASE PRESENTATION

Three example cases, including focusing on key questions which could involve the nephrologists are reported in detail. They include a cancer-related Goodpasture Syndrome, the peculiar toxic effects of pemetrexed on tubular cells, and the intriguing relationship between bevacizumab and cryoglobulinemic glomerulonephritis.

CONCLUSION

As shown by these 3 example cases, nephrologists need to be open-minded with regard to kidney biopsy in order to get a timely diagnosis. Nephrologists also need to improve their knowledge of cancer biology and therapy in order to prevent kidney problems, manage therapy-related immune-mediated disorders, and improve patient life expectancy.

Prioritizing potential ACE2 inhibitors in the COVID-19 pandemic: Insights from a molecular mechanics-assisted structure-based virtual screening experiment

Angiotensin-converting enzyme 2 (ACE2) is a membrane-bound zinc metallopeptidase that generates the vasodilatory peptide angiotensin 1-7 and thus performs a protective role in heart disease. It is considered an important therapeutic target in controlling the COVID-19 outbreak, since SARS-CoV-2 enters permissive cells via an ACE2-mediated mechanism. The present in silico study attempted to repurpose existing drugs for use as prospective viral-entry inhibitors targeting human ACE2. Initially, a clinically approved drug library of 7,173 ligands was screened against the receptor using molecular docking, followed by energy minimization and rescoring of docked ligands. Finally, potential binders were inspected to ensure molecules with different scaffolds were engaged in favorable contacts with both the metal cofactor and the critical residues lining the receptor's active site. The results of the calculations suggest that lividomycin, burixafor, quisinostat, fluprofylline, pemetrexed, spirofylline, edotecarin, and diniprofylline emerge as promising repositionable drug candidates for stabilizing the closed (substrate/inhibitor-bound) conformation of ACE2, thereby shifting the relative positions of the receptor's critical exterior residues recognized by SARS-CoV-2. This study is among the rare ones in the relevant scientific literature to search for potential ACE2 inhibitors. In practical terms, the drugs, unmodified as they are, may be introduced into the therapeutic armamentarium of the ongoing fight against COVID-19 now, or their scaffolds may serve as rich skeletons for designing novel ACE2 inhibitors in the near future.

Targeted drug therapy in non-small cell lung cancer: Clinical significance and possible solutions-Part I

INTRODUCTION

Non-small cell lung cancer (NSCLC) comprises of 84% of all lung cancer cases. The treatment options for NSCLC at advanced stages are chemotherapy and radiotherapy. Chemotherapy involves conventional nonspecific chemotherapeutics, and targeted-protein/receptor-specific small molecule inhibitors. Biologically targeted therapies such as an antibody-based immunotherapy have been approved in combination with conventional therapeutics. Approved targeted chemotherapy is directed against the kinase domains of mutated cellular receptors such as epidermal growth factor receptor (EGFR), anaplastic lymphoma kinases (ALK), neurotrophic receptor kinases (NTRK) and against downstream signaling molecules such as BRAF (v-raf murine sarcoma viral oncogene homolog B1). Approved biologically targeted therapy involves the use of anti-angiogenesis antibodies and antibodies against immune checkpoints.

AREAS COVERED

The rationale for the employment of targeted therapeutics and the resistance that may develop to therapy are discussed. Novel targeted therapeutics in clinical trials are also included.

EXPERT OPINION

Molecular and histological profiling of a given tumor specimen to determine the aberrant onco-driver is a must before deciding a targeted therapeutic regimen for the patient. Periodic monitoring of the patients response to a given therapeutic regimen is also mandatory so that any semblance of resistance to therapy can be deciphered and the regimen may be accordingly altered.

Preparation and Evaluation of Stearylamine-Bearing Pemetrexed Disodium-Loaded Cationic Liposomes In Vitro and In Vivo

Pemetrexed disodium (PMX) stands out in the treatment of non-small cell lung cancer (NSCLC), but with short half-life and toxic side effects. This study was to design cationic liposomes for targeting delivery PMX to the lungs. The PMX cationic liposome was prepared by thin-film hydration using stearylamine (SA) as the positive component of charge-regulating charge. Then, the PMX cationic liposome (SA-PMX-Lips) was characterized by particle size, morphology, entrapment efficiency (EE), and drug loading (DL). Finally, the drug release behavior in vitro, the pharmacokinetic study, and tissue distribution of SA-PMX-Lips were evaluated separately, with PMX solution (PMX-Sol) and PMX liposome (PMX-Lips) as the control. According to results, SA-PMX-Lips were spherical and the particle size was 219.7 ± 4.97 nm with a narrow polydispersity index (PDI) (0.231 ± 0.024) and a positive zeta potential 22.2 ± 0.52 mV. Its EE was 92.39 ± 1.94% and DL was 9.15 ± 0.07%. The results of in vitro and in vivo experiments showed that SA-PMX-Lips released slowly, prolonged retention time and increased the value of AUC. More notably, SA-PMX-Lips could improve the accumulation of drugs in the lungs and the relative uptake rate (Re) was 2.35 in the lungs, which indicated its lung targeting. In summary, SA-PMX-Lips showed the potential for the effective delivery of PMX and the treatment of NSCLC.

Supramolecular Amphiphilic Assembly Formed by the Complexation of Calixpyridinium with Alimta

In this work, the host-guest interaction between calixpyridinium and anionic anticancer drug Alimta was studied in aqueous media. Spherical supramolecular amphiphilic assembly rather than simple complex was accidentally fabricated by the complexation of calixpyridinium with Alimta. It is the third kind of anionic guest to be discovered to form the higher-order assembly by the complexation of calixpyridinium besides polyanionic guest and anionic gemini surfactant guest. The finding of this assembly approach supplies a new idea to construct various self-assembly architectures in water via the complexation of calixpyridinium with anionic drugs. The resulting calixpyridinium-drug assemblies may also have the potential to adjust the effects of drugs.

FGF2-FGFR1 pathway activation together with thymidylate synthase upregulation is induced in pemetrexed-resistant lung cancer cells

Pemetrexed (MTA) is a folate antimetabolite used for treating non-small cell lung cancer. To elucidate the mechanisms of pemetrexed resistance in lung cancer, we established pemetrexed-resistant sublines in PC9 (mutant EGFR) and H1993 (wild-type EGFR) lung adenocarcinoma cell lines (PC9-MTA, H1993-MTA). Gene expression profile comparison by microarray analyses revealed enhanced fibroblast growth factor 2 (FGF2) and FGF receptor 1 (FGFR1) expression, confirmed by Western blotting, enzyme-linked immunosorbent assay, and reverse transcription-polymerase chain reaction. ERK phosphorylation was increased in PC9-MTA but decreased in H1993-MTA along with decreased downstream signaling molecule phosphorylation. Cellular morphological change from epithelial to spindle-shape together with increased mesenchymal marker protein expression was observed in H1993-MTA. SiRNA-mediated FGF2 knockdown partially restored pemetrexed sensitivity in both lines, whereas anti-FGFR1 inhibitor PD173074 restored pemetrexed sensitivity in PC9-MTA. FGF2 or FGFR1 inhibition decreased pERK levels in PC9-MTA but increased pEGFR levels together with downstream signaling molecule activation and reversed epithelial-mesenchymal transition marker protein expression in H1993-MTA. Although thymidylate synthase strongly facilitates the development of pemetrexed resistance, our results reveal involvement of the FGF2-FGFR1 pathway in pemetrexed resistance in lung cancer cells and suggest that cellular function alterations induced by FGF2-FGFR1 pathway activation depend on the innate feature of cancer cells.

Pemetrexed-loaded nanoparticles targeted to malignant pleural mesothelioma cells: an in vitro study

PURPOSE

Malignant pleural mesothelioma (MPM) is an aggressive tumor characterized by poor prognosis. Its incidence is steadily increasing due to widespread asbestos exposure. There is still no effective therapy for MPM. Pemetrexed (Pe) is one of the few chemotherapeutic agents approved for advanced-stage disease, although the objective response to the drug is limited. The use of gold nanoparticles (GNPs) as a drug delivery system promises several advantages, including specific targeting of malignant cells, with increased intracellular drug accumulation and reduced systemic toxicity, and, in the case of MPM, direct treatment administration into the pleural space. This study aims at exploring CD146 as a potential MPM cell-specific target for engineered Pe-loaded GNPs and to assess their effectiveness in inhibiting MPM cell line growth.

METHODS

MPM cell lines and primary cultures obtained by pleural effusions from MPM patients were assayed for CD146 expression by flow cytometry. Internalization by MPM cell lines of fluorescent dye-marked GNPs decorated with a monoclonal anti CD146 coated GNPs (GNP-HC) was proven by confocal microscopy. The effects of anti CD146 coated GNPs loaded with Pe (GNP-HCPe) on MPM cell lines were evaluated by cell cycle (flow cytometry), viability (MTT test), clonogenic capacity (soft agar assay), ROS production (electric paramagnetic resonance), motility (wound healing assay), and apoptosis (flow cytometry).

RESULTS

GNP-HC were selectively uptaken by MPM cells within 1 hour. MPM cell lines were blocked in the S cell cycle phase in the presence of GNP-HCPe. Both cell viability and motility were significantly affected by nanoparticle treatment compared to Pe. Apoptotic rate and ROS production were significantly higher in the presence of nanoparticles. Clonogenic capacity was completely inhibited following nanoparticle internalization.

CONCLUSION

GNP-HCPe treatment displays in vitro antineoplastic action and is more effective than Pe alone in inhibiting MPM cell line malignant phenotype. The innovative use of specifically targeted GNPs opens the perspective of local intrapleural administration to avoid normal cell toxicity and enhance chemotherapy efficacy.

Combined hyaluronate-based films loaded with pemetrexed and cisplatin for the treatment of malignant pleural mesothelioma: Preliminary evaluation in an orthotopic tumor recurrence model

Malignant pleural mesothelioma (MPM) is a rare malignancy characterized by a long latency period of 20-50 years after exposure to the main aetiology agent that is asbestos. MPM treatments include surgery, chemotherapy, and radiation therapy, with the combination pemetrexed and cisplatin being the standard chemotherapy approach. Despite this multimodality therapy one of the major issues after surgery is the high rate of local recurrence of the tumor. One possible approach would be the intrapleural application of implants loaded with anticancer drug to be applied during surgery to prevent local tumor recurrence. The implant proposed in the present work is a polymeric film of hyaluronic acid loaded with pemetrexed. The film developed is a hydrophilic, thin and flexible film sufficiently resistant to be applied intrapleurally adhering to the mesothelial surface. The release of pemetrexed from the film was found to be complete within2 h in phosphate buffered saline. In an orthotopic model of mesothelioma recurrence in rats, pemetrexed loaded films showed the same antitumor efficacy of pemetrexed disodium solutions administered intravenously or intrapleurally, while when administered in combination with cisplatin-loaded hyaluronate film, the implants almost completely prevented tumor recurrence. The local administration of drug-loaded polymer implants appears an ideal chemotherapy strategy especially for patients in which surgery is already selected as a viable therapeutic option.

Chemotherapy with or without pemetrexed as second-line regimens for advanced non-small-cell lung cancer patients who have progressed after first-line EGFR TKIs: a systematic review and meta-analysis

Purpose

The development of acquired resistance to the first-line epidermal growth factor-tyrosine kinase inhibitor (EGFR-TKI) treatment in non-small-cell lung cancer (NSCLC) is inevitable, and most of these patients needed second-line chemotherapy. Furthermore, the optimum chemotherapeutic regimen is unclear. The aim of this meta-analysis was to evaluate the chemotherapeutic regimens “with-pemetrexed” versus “non-pemetrexed” in advanced NSCLC patients who had progressed after first-line EGFR-TKIs.

Materials and methods

We searched PubMed, Embase, Cochrane Library, and the Web of science for relevant clinical trials. Outcomes analyzed were response rate (RR), disease control rate (DCR), 1-year survival rate (1-year SR), progression-free survival (PFS), and overall survival (OS).

Results

One randomized controlled trial (RCT) and three retrospective studies were included in this meta-analysis, covering a total of 354 patients. The results showed that there was no significant difference between with-pemetrexed arm and non-pemetrexed arm in RR (OR 1.43, 95% CI 0.85–2.41, P=0.18), DCR (OR 1.5, 95% CI 0.94–2.39, P=0.09), and 1-year SR (OR 1.47, 95% CI 0.79–2.74, P=0.22). But the with-pemetrexed chemotherapeutic regimens significantly improved the PFS (HR 0.61, 95% CI 0.46–0.81, P=0.0005) and OS (HR 0.62, 95% CI 0.42–0.90, P=0.01).

Conclusion

The second-line with-pemetrexed chemotherapeutic regimens provided significantly longer PFS and OS than non-pemetrexed chemotherapeutic regimens. These findings indicate that the with-pemetrexed chemotherapeutic regimen may be an optimal second-line chemotherapeutic regimen for patients with advanced NSCLC following EGFR-TKI failure.

The role of pemetrexed in recurrent epithelial ovarian cancer: A scoping review

Ovarian cancer is the leading cause of mortality among gynecologic malignancies, with most cases diagnosed at an advanced stage. Despite an initial response, most develop a recurrence and subsequent resistance to standard therapies. Pemetrexed (AlimtaTM) is a new generation multi-targeted antifolate initially approved for the treatment of malignant pleural mesothelioma. In recent years, it has shown promise in the treatment of recurrent epithelial ovarian cancer. In this review, we outline the current literature and discuss the future of pemetrexed in the setting of recurrent epithelial ovarian cancer.

Chemotherapy treatment in malignant pleural mesothelioma: a difficult history

Malignant pleural mesothelioma (MPM) is a rare neoplasm that typically arises from mesothelial surfaces of the pleural cavity. Despite treatment improvements, it carries a dismal prognosis. The majority of patients either have unresectable disease or are not candidates for surgery due to medical comorbidities or old age. For such patients, chemotherapy (CT) represents the gold-standard treatment. To date, combination CT with cisplatin plus pemetrexed represents the most widely used regimen in first-line setting for patients with unresectable MPM. Other first-line options are currently available, including the use of raltitrexed instead of pemetrexed combined with platinum. In this review, we discuss the role of CT in MPM mainly focusing on the results of the trials conducted in first-line setting.

Renal failure during chemotherapy: renal biopsy for assessing subacute nephrotoxicity of pemetrexed

BACKGROUND

Pemetrexed, a multitargeted antifolate cytotoxic agent, is currently used primarily in combination with cisplatin for metastatic non-small cell lung cancer and for malignant mesothelioma. Acute renal toxicity of pemetrexed has been recently described with polychemotherapy, in which the individual responsibility of each drug is difficult to establish. Only one recent report documents renal involvement in long-term exposed patients.

CASE PRESENTATION

We report on a case of rapidly progressive nephropathy leading to the cessation of platinum salts and the secondary interruption of pemetrexed and bevacizumab. Acute tubular necrosis shown on the renal biopsy could potentially be due to pemetrexed. Persistent severe renal failure after the resumption of all drugs led to new treatment lines with gemcitabine (while the glomerular filtration rate was below 30 ml/min/1.73m2), then followed by Taxol.

CONCLUSIONS

The optimal strategy with regard to renal complications in cancer patients is not clear. Acute or chronic loss in renal function generally leads to a new treatment line, possibly impairing the overall success of the treatment. The use of chemotherapy in patients with a glomerular filtration rate below 30 ml/min/1.73m2 is usually associated with an increased risk of side effects when not contraindicated by renal elimination of the drug.

Metformin synergistic pemetrexed suppresses non-small-cell lung cancer cell proliferation and invasion in vitro

The aim of this study was to investigate whether metformin in combination with pemetrexed has an effect on the treatment of non-small-cell lung cancer (NSCLC) models and to explore the related molecular mechanism. The half maximal inhibitory concentration (IC50) and combination index (CI) of metformin and pemetrexed were detected by the CCK8 assay to assess the antiproliferative and therapeutic effects of the two-drug combination. Flow cytometry (FCM) and invasion assays were used to estimate the variation in apoptosis rate and invasion ability of the differently treated NSCLC cell lines. Apoptotic markers were detected by western blotting to validate the data related to the antiproliferation and proapoptosis effects. Metformin monotherapy inhibited the growth of NSCLC cell lines and reduced the invasion ability to different degrees compared with the control groups (P < 0.05). Metformin in combination with pemetrexed produced a synergistic effect (CI < 0.90) compared with the two drugs in monotherapy in the three tested NSCLC cell lines. Metformin in combination with pemetrexed significantly increased the cell numbers of HCC827 cells at S phase (P < 0.001), and the combination therapy had no influence on the A549 and H1975 cell lines. We found that combining metformin with pemetrexed induced more cell apoptosis than metformin or pemetrexed used alone (P < 0.05), which was validated by the apoptotic markers. These results demonstrate that the combination of metformin and pemetrexed has a synergistic effect on the treatment of NSCLC cell lines by inducing apoptosis or blocking the cell cycle. Our data indicate that the combination of metformin and pemetrexed could have beneficial antitumor effects on NSCLC cells in vitro.

Lipid drug conjugate nanoparticle as a potential nanocarrier for the oral delivery of pemetrexed diacid: Formulation design, characterization, ex vivo, and in vivo assessment

The present work was to develop lipid drug conjugated (LDC) nanoparticles for the potential oral delivery of pemetrexed diacid (PTX) and evaluation of its in vitro, ex vivo and in vivo potentials. The LDC was prepared by salt formation of PTX with stearic acid and followed by cold homogenization technique to produce the LDC nanoparticles. FTIR analysis of LDC proved the presence of amide bond in LDC powder indicating the conjugation between drug and lipid. LDC nanoparticles was found to have particle size 121.9±1.85nm and zeta potential -51.6mV±1.23 and entrapment efficiency 81.0±0.89%. TEM images revealed spherical morphology and were in corroboration with particle size measurements. Ex vivo gut permeation studies revealed a very good enhancement in permeation of drug present in the LDC as compared to plain drug solution and were confirmed by CLSM. MTT assay conformed significant% toxicity at the end of 24h and 48h. Furthermore, the AUC_0-24 of PTX from the optimized LDC nanoparticels was found to be 4.22 folds higher than that from PTX suspension on oral administration. Thus, LDC has high potential for the oral delivery of PTX in cancer therapy and future prospects for the industrial purpose.

Increased risk of severe infections in non-small-cell lung cancer patients treated with pemetrexed: a meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Infections related to pemetrexed have been reported in clinical trials. It is not yet clear whether this drug increases infection risk or not. This meta-analysis assessed the overall incidence and risk of severe infections (≥ grade 3) associated with the use of pemetrexed in non-small-cell lung cancer patients.

METHODS

The databases of PubMed, Embase, and the Cochrane Library were searched for relevant studies published up to December 2015. Eligible studies included randomized controlled trials (RCTs) of pemetrexed for non-small-cell lung cancer patients that reported grade 3-5 infection and febrile neutropenia. Summary incidence rates, relative risks (RRs) and 95% confidence intervals (CIs) were calculated by using either random-effects or fixed-effects models, according to the heterogeneity of the included studies.

RESULTS

Seven randomized controlled trials were included, comprising 1848 patients. The incidence of severe infection and febrile neutropenia due to pemetrexed was 5.7% (95% CI: 3.2-8.3%) and 1.3% (95% CI: 0.7-2.0%), respectively. The use of pemetrexed was associated with an increased risk of severe infection (RR 1.61, 95% CI: 1.07-2.44, P = .02) and febrile neutropenia (RR 4.28, 95% CI: 1.08-17.01, P = .04).

CONCLUSION

The use of pemetrexed was associated with an increased risk of developing severe infections and febrile neutropenia in non-small-cell lung cancer patients. Frequent clinical monitoring and management of infections should be emphasized during pemetrexed treatment. More studies are needed to reveal the mechanism of the increased risk of severe infections.

Astaxanthin enhances pemetrexed-induced cytotoxicity by downregulation of thymidylate synthase expression in human lung cancer cells

Pemetrexed, a multitargeted antifolate agent, has demonstrated clinical activity in non-small cell lung cancer (NSCLC) cells. Increased expression of thymidylate synthase (TS) is thought to be associated with resistance to pemetrexed. Astaxanthin exhibits a wide range of beneficial effects including anti-cancer and anti-inflammatory properties. In this study, we showed that down-regulating of TS expression in two NSCLC cell lines, human lung adenocarcinoma H1650 and squamous cell carcinoma H1703 cells, with astaxanthin were associated with decreased MKK1/2-ERK1/2 activity. Enforced expression of constitutively active MKK1 (MKK1-CA) vector significantly rescued the decreased TS mRNA and protein levels in astaxanthin-treated NSCLC cells. Combined treatment with a MKK1/2 inhibitor (U0126 or PD98059) further decreased the TS expression in astaxanthin-exposed NSCLC cells. Knockdown of TS using small interfering RNA (siRNA) or inhibiting ERK1/2 activity enhanced the cytotoxicity and cell growth inhibition of astaxanthin. Combination of pemetrexed and astaxanthin resulted in synergistic enhancing cytotoxicity and cell growth inhibition in NSCLC cells, accompanied with reduced activation of phospho-MKK1/2, phopho-ERK1/2, and TS expression. Overexpression of MKK1/2-CA reversed the astaxanthin and pemetrexed-induced synergistic cytotoxicity. Our findings suggested that the down-regulation of MKK1/2-ERK1/2-mediated TS expression by astaxanthin is an important regulator of enhancing the pemetrexed-induced cytotoxicity in NSCLC cells.

Lansoprazole Exacerbates Pemetrexed-Mediated Hematologic Toxicity by Competitive Inhibition of Renal Basolateral Human Organic Anion Transporter 3

Pemetrexed, a multitargeted antifolate, is eliminated by tubular secretion via human organic anion transporter 3 (hOAT3). Although proton pump inhibitors (PPIs) are frequently used in cancer patients, the drug interaction between PPIs and pemetrexed remains to be clarified. In this study, we examined the drug interaction between pemetrexed and PPIs in hOAT3-expressing cultured cells, and retrospectively analyzed the impact of PPIs on the development of hematologic toxicity in 108 patients who received pemetrexed and carboplatin treatment of nonsquamous non-small cell lung cancer for the first time between January 2011 and June 2015. We established that pemetrexed was transported via hOAT3 (Km = 68.3 ± 11.1 µM). Lansoprazole, rabeprazole, pantoprazole, esomeprazole, omeprazole, and vonoprazan inhibited hOAT3-mediated uptake of pemetrexed in a concentration-dependent manner. The inhibitory effect of lansoprazole was much greater than those of other PPIs and the apparent IC50 value of lansoprazole against pemetrexed transport via hOAT3 was 0.57 ± 0.17 µM. The inhibitory type of lansoprazole was competitive. In a retrospective study, multivariate analysis revealed that coadministration of lansoprazole, but not other PPIs, with pemetrexed and carboplatin was an independent risk factor significantly contributing to the development of hematologic toxicity (odds ratio: 10.004, P = 0.005). These findings demonstrated that coadministration of lansoprazole could exacerbate the hematologic toxicity associated with pemetrexed, at least in part, by competitive inhibition of hOAT3. Our results would aid clinicians to make decisions of coadministration drugs to avoid drug interaction-induced side effects for achievement of safe and appropriate chemotherapy with pemetrexed.

The ERK-ZEB1 pathway mediates epithelial-mesenchymal transition in pemetrexed resistant lung cancer cells with suppression by vinca alkaloids

High thymidylate synthase (TS) level in cancer tissue is considered to result in resistance to pemetrexed therapy for advanced stages of nonsquamous non-small cell lung cancers. To further investigate the mechanism of pemetrexed resistance and potential prognostic outcomes in lung cancer, we established pemetrexed-resistant lung adenocarcinoma cell sublines from CL1 harboring a mutated TP53 gene (R248W) and A549 harboring wild-type TP53. We found the TS expression is upregulated in both pemetrexed-resistant sublines and the reduced TS level achieved through shRNA inhibition resulted in higher pemetrexed sensitivity. We also demonstrated that the acquisitions of pemetrexed resistance enhances epithelial–mesenchymal transition (EMT) in vivo with a mice animal model and in vitro with CL1 and A549 sublines, which was associated with upregulation of ZEB1 which, in turn, downregulates E-cadherin and upregulates fibronectin. When ERK1/2 phosphorylation was reduced by an inhibitor (U0126) or siRNA inhibition, both pemetrexed-resistant sublines reduced their migration and invasion abilities. Therefore, the ERK-mediated pathways induce apoptosis with pemetrexed treatment, and may in turn mediate EMT when cancer cells are resistant to pemetrexed. We further demonstrated that the growth of pemetrexed-resistant tumors could be inhibited by vinblastine in vivo and vincristine in vitro. Our data indicate that pemetrexed resistance could be relieved by non-cross-resistant chemotherapeutic drugs such as vinca alkaloids and might be independent to TP53 status. Furthermore, the phosphorylation of ERK was reduced by vincristine. This finding provides a new insight for overcoming pemetrexed resistance and metastasis by application of vinca alkaloids.

Safety profiles of first-line therapies for metastatic non-squamous non-small-cell lung cancer

INTRODUCTION

Lung cancer still represents the leading cause of death for cancer. About the 70% of diagnosis are in advanced-stage. Non-small-cell lung cancer (NSCLC) represents the 85% of all diagnosed lung cancers and non-squamous histology represents the 40% of all NSCLC. First-line therapies increase survival, control symptoms and improve quality of life, compared with best supportive care. It is crucial to choose a treatment with a low impact on patient's life considering the related toxicities.

AREAS COVERED

Adverse events (AEs) of first-line therapies for non-squamous NSCLC are here reviewed and discussed, from evidences in clinical trials conducting to drugs approval.

EXPERT OPINION

For advanced disease, palliation and preserving patients QoL are still the primary goal of treatment. Therefore, differing toxicity profiles are often a deciding factor in first-line and also maintenance setting for non-squamous NSCLC. Special attention is necessary to renal function and drugs' nephrotoxicity. Moreover, it is to consider the specific AEs of drugs classes: hypertension, bleeding, and proteinuria, for anti-VEGF therapy; skin toxicity, diarrhea, interstitial lung disease for TKIs; vision disorders, and hepatotoxicity for ALK-inhibitor. It is important to select patients for a treatment on the basis of their comorbidities and the presence of risk factors.

Present Advances and Future Perspectives of Molecular Targeted Therapy for Osteosarcoma

Osteosarcoma (OS) is a bone cancer mostly occurring in pediatric population. Current treatment regime of surgery and intensive chemotherapy could cure about 60%-75% patients with primary osteosarcoma, however only 15% to 30% can be cured when pulmonary metastasis or relapse has taken place. Hence, novel precise OS-targeting therapies are being developed with the hope of addressing this issue. This review summarizes the current development of molecular mechanisms and targets for osteosarcoma. Therapies that target these mechanisms with updated information on clinical trials are also reviewed. Meanwhile, we further discuss novel therapeutic targets and OS-targeting drug delivery systems. In conclusion, a full insight in OS pathogenesis and OS-targeting strategies would help us explore novel targeted therapies for metastatic osteosarcoma.

Study of Pemetrexed-based Chemotherapy for Patients with Locally Advanced or Metastatic Cancers

PURPOSE

This study was conducted to observe the efficacy and safety of pemetrexed based chemotherapy in treating patients with locally advanced or metastatic cancers as first-line, second-line or third-line therapy.

MATERIALS AND METHODS

From May 2011 to January 2015, we recruited 29 patients with advanced breast cancer, 19 patients with advanced ovary cancer, 17 patients with advanced esophageal cancer,5 patients with advanced gallbladder cancer,5 patients with advanced cervical cancer and 1 patient with advanced tongue cancer in Jiangsu Cancer Hospital and Research Institute.All of them were pathologically confirmed and treated with pemetrexed based chemotherapy. After two cycles of treatment,efficacy and safety can be evaluated.

RESULTS

For pemetrexed based regimens,including 76 patients with 6 kinds of advanced cancer were considered eligible for inclusion. Complete remission represents CR, partial remission represents PR, stable disease represents SD, progressive disease represents PD. Among 29 patients with advanced breast cancer, 4 patients chose pemetrexed based regimens as second-line treatment,1 of them was PR,the other 3 got SD. The last 25 patients made use of this chemotherapy as third-line treatment, except one patient could not be assessed, 2 of them got PR,6 of them got SD,the remaining 16 of them finally were PD.19 patients with advanced ovary cancer,5 patients used this regimens as second-line treatment, 3 of them got PD,the remaining patients got SD, respectively. The last 14 patients made use of pemetrexed based regimens as third-line treatment,. RR (CR+PR) was 28.5%. Among 17 patients with advanced esophageal cancer, 2 patients made use of pemetrexed based regimens as first-line treatment,both of them got PR.4 of them used this chemotherapy as second-line regimen, except 2 patients could not be assessed,the remaining 2 was PD at last. The last 11 patients was third-line users, RR (CR+PR) was 18.2%. Among 5 patients with advanced gallbladder cancer, pemetrexed based regimens was used in 1 patient as first- line treatment and 1 patient as second-line treatment. The curative effect was SD and PD, respectively. 3 patients accepted pemetrexed based regimens as third-line treatment, 2 of them got PD as results and another was SD. Among 5 patients with advanced cervical cancer, just 1 patient adopted pemetrexed based regimens as first-line treatment, whose curative effect was PR.2 patients chose this chemotherapy regimens as second-line treatment. Both of them got PD as their consequence. The last 2 patients made use of the regimens as third-line treatment, the effect of them was PD and SD, respectively. The one who with advanced tongue cancer, pemetrexed based regimens was used as second-line treatment, and the consequence was PD. About 71.1% patients experienced bone marrow suppression. Among them, 5 patients reached 4 grade. Other toxicity of pemetrexed were neurotoxicity, fatigue, diarrhea, dysphagia and vomiting. No treatment related death occurred with pemetrexed-based treatment.

CONCLUSIONS

Pemetrexed based chemotherapy has considerable effect in patients with advanced cancers such as breast cancer,esophageal cancer and ovary cancer. More randomly clinical trials are needed to verify the results.

Phase II study on pemetrexed-based chemotherapy in treating patients with metastatic gastric cancer not responding to prior palliative chemotherapy

PURPOSE

This study was to determine the efficacy and safety of pemetrexed based chemotherapy in treating patients with metastatic gastric cancer who failed to respond to first and (or) second line chemotherapy.

PATIENTS AND METHODS

Metastatic gastric cancer patients who failed first and (or) second line chemotherapy, were enrolled. All patients were recruited from Jiangsu Cancer Hospital and Research Institute, and were treated with pemetrexed 500 mg/m2 (intravenous; on day 1), and a platinum (or irinotecan) every 3 weeks until disease progression, or intolerable toxicity. Evaluation on efficacy was conducted after two cycles of chemotherapy using the Response Evaluation Criteria for Solid Tumors. Toxicity was recorded according to National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0.

RESULTS

From Jun 2011 to May 2013, 23 patients were enrolled. All eligible 23 patients completed at least 2 cycles of chemotherapy with pemetrexed based chemotherapy, and were evaluable. Their median age was 55 years (range 40 to 78 years). Seventeen patients were male and 6 female. Three patients (13%) achieved partial response, five patients (22%) stable, 15 patients (65%) with disease progression, and none with complete response. Grade 2 neutrophil suppression occurred in 4.3%, grade 3 in 13% of patients, and no grade 4 was reported. Thrombocytopenia was encountered as follows: 4.3% grade 2, 4.3% grade 3 and 4.3% grade 4. Incidence of anemia was 34.8% in grade 2, 8.7% grade 3 and 0% grade 4. Only 4.3% of patients required packed red blood cell infusion. Elevated transaminase were 4.3% in grade 2 and 0% in grade 3 or 4. Other toxicity included oral mucositis.

CONCLUSIONS

Pemetrexed based chemotherapy is mildly effective in treating patients with metastatic gastric cancer with tolerable toxicity.

Pemetrexed as a component of first-, second- and third- line chemotherapy in treating patients with metastatic lung adenocarcinoma

PURPOSE

The current research was conducted to investigate the efficacy and safety of pemetrexed given continuously as a basement agent for first-, second- to third line chemotherapy of patients with metastatic lung adenocarcinoma.

PATIENTS AND METHODS

Patients with metastatic lung adenocarcinoma who were diagnosed in Jiangsu Cancer Hospital and Research Insitute, were enrolled. All received pemetrexed 500 mg/m2 (intravenous; on day 1), and another chemotherapieutic agent every 3 weeks until disease progression, or intolerable toxicity. Then the patients were changed to a second line chemotherapy that was still based on pemetrexed 500 mg/m2 and another chemotherapeutic agent differing from the first line example, until disease progression, or intolerable toxicity. When third line chemotherapy was needed, pemetrexed 500 mg/m2 and another new chemotherapeutic agent were combined until disease progression. Evaluation of efficacy was conducted after two cycles of chemotherapy using the Response Evaluation Criteria for Solid Tumors. Toxicity was recorded according to NCI Criteria for Adverse Events version 3.0.

RESULTS

From January 2010 to September 2013, 15 patients were enrolled. Their median age was 56 years (range 43 to 77 years). Eight patients were male and 7 female. Five patients (33.3%) achieved PR, while 6 patients (40.0%) remained stable, no CR on first line; and 1 PR (7.7%), 5 stable (38.5%) were recorded when pemetrexed was ordered in second line; 5 patients (41.7%) were stable after pemetrexed was combined in third line; no complete response was observed. Main side effects were grade 1 to 2 neutrophil suppression and thrombocytopenia. Other toxicities included elevated transaminase and oral mucositis, but no treatment related death occurred.

CONCLUSIONS

Pemetrexed continuously as a basement agent from first-, second- to third line chemotherapy is mildly effective in treating patients with metastatic lung adenocarcinoma with tolerable toxicity.

Inhibition of MEK/ERK activation attenuates autophagy and potentiates pemetrexed-induced activity against HepG2 hepatocellular carcinoma cells

Identification of efficient chemo-therapeutic/chemo-preventive agents for treatment of hepatocellular carcinoma (HCC) is important. In this study, we examined the activity of pemetrexed, an anti-folate chemotherapy drug, against HepG2 human HCC cells. Pemetrexed treatment in vitro exerted weak but significant cytotoxic activity against HepG2 cells. When analyzing the possible pemetrexed-resistance factors, we indentified that pemetrexed treatment in HepG2 cells induced cyto-protective autophagy activation, evidenced by GFP-light chain 3B (LC3B) puncta formation, p62 downregulation and Beclin-1/LC3B-II upregulation. Correspondingly, autophagy inhibitors, including bafliomycin A1, 3-methyladenine and chloroquine, enhanced pemetrexed-induced cytotoxicity against HepG2 cells. Further, RNAi-mediated knockdown of Beclin-1 in HepG2 cells also increased pemetrexed sensitivity. Pemetrexed activated MEK (mitogen-activated protein kinase/ERK kinase)/ERK (extracellular-signal-regulated kinase) signaling in HepG2 cells, which was required for autophagy induction. Pharmacological inhibition of MEK/ERK activation attenuated pemetrexed-induced autophagy, enhanced HepG2 cell death and apoptosis. In summary, pemetrexed activates MEK/ERK-dependent cyto-protective autophagy, and inhibition of this pathway potentiates pemetrexed's activity in HepG2 cells.