Sunitinib malate for the treatment of metastatic renal cell carcinoma and gastrointestinal stromal tumors

Design, Synthesis, Anti-Cancer, Anti-Inflammatory and In Silico Studies of 3-Substituted-2-Oxindole Derivatives

This study focuses on the design and synthesis of 3-substituted-2-oxindole derivatives aimed at developing dual-active molecules with anti-cancer and anti-inflammatory properties. The molecules were designed with diverse structural and functional features while adhering to Lipinski, Veber, and Leeson criteria. Physicochemical properties were assessed using SWISSADME to ensure drug-likeness and favourable pharmacokinetics. Multistep synthetic procedures were employed for molecule synthesis. In vitro evaluations confirmed the dual activity of the derivatives, with specific emphasis on the significance of dialkyl aminomethyl substitutions for potency against various cell lines. 4 a exhibited GI50 value 3.00E-05 against MDA-MB-231, 4 b has shown GI50 value 2E-05 against MDA-MB-231, 4 c has shown GI50 value 6E-05 against VERO, 4 d has shown GI50 value 8E-05 each against both the MDA-MB-231 and MCF-7 and 4 e has shown GI50 values 2E-05 and 5E-05 each against both the MCF-7 and VERO. The analysis indicates that compounds 3 c (71.19 %), 3 e (66.84 %), and 3 g (63.04 %) exhibited significant anti-inflammatory activity. Additionally, in silico binding free energy analysis and interaction studies revealed significant correlations between in vitro and computational data, identifying compounds 4 d, 4 e, 3 b, 3 i, and 3 e as promising candidates. Key residues such as Glu917, Cys919, Lys920, Glu850, Lys838, and Asp1046 were found to play critical roles in ligand binding and kinase inhibition, providing valuable insights for designing potent VEGFR2 inhibitors. The Quantum Mechanics-based Independent Gradient Model analysis further highlighted the electronic interaction landscape, showing larger attractive peaks and higher electron density gradients for compounds 4 d and 4 e compared to Sunitinib, suggesting stronger and more diverse attractive forces. These findings support the potential of these compounds for further development and optimization in anticancer drug design.

Self-assembled lipid-based nanoparticles for chemotherapy against breast cancer

Self-assembled lipid-based nanoparticles have been shown to have improved therapeutic efficacy and lower toxic side effects. Breast cancer is a common type of malignant tumor in women. Conventional drugs such as doxorubicin (DOX) have shown low therapeutic efficacy and high drug toxicity in antitumor therapy. This paper surveys research on self-assembled lipid-based nanoparticles by categorizing them under three groups: self-assembled liposomal nanostructures, self-assembled niosomes, and self-assembled lipid-polymer hybrid nanoparticles. Subsequently, the structural features and operating mechanisms of each group are summarized individually along with examples of representative drugs from each group.

Targeting the RAS upstream and downstream signaling pathway for cancer treatment

Cancer often involves the overactivation of RAS/RAF/MEK/ERK (MAPK) and PI3K-Akt-mTOR pathways due to mutations in genes like RAS, RAF, PTEN, and PIK3CA. Various strategies are employed to address the overactivation of these pathways, among which targeted therapy emerges as a promising approach. Directly targeting specific proteins, leads to encouraging results in cancer treatment. For instance, RTK inhibitors such as imatinib and afatinib selectively target these receptors, hindering ligand binding and reducing signaling initiation. These inhibitors have shown potent efficacy against Non-Small Cell Lung Cancer. Other inhibitors, like lonafarnib targeting Farnesyltransferase and GGTI 2418 targeting geranylgeranyl Transferase, disrupt post-translational modifications of proteins. Additionally, inhibition of proteins like SOS, SH2 domain, and Ras demonstrate promising anti-tumor activity both in vivo and in vitro. Targeting downstream components with RAF inhibitors such as vemurafenib, dabrafenib, and sorafenib, along with MEK inhibitors like trametinib and binimetinib, has shown promising outcomes in treating cancers with BRAF-V600E mutations, including myeloma, colorectal, and thyroid cancers. Furthermore, inhibitors of PI3K (e.g., apitolisib, copanlisib), AKT (e.g., ipatasertib, perifosine), and mTOR (e.g., sirolimus, temsirolimus) exhibit promising efficacy against various cancers such as Invasive Breast Cancer, Lymphoma, Neoplasms, and Hematological malignancies. This review offers an overview of small molecule inhibitors targeting specific proteins within the RAS upstream and downstream signaling pathways in cancer.

Current status of drugs targeting PDGF/PDGFR

As an important proangiogenic factor, platelet-derived growth factor (PDGF) and its receptor PDGFR are highly expressed in a variety of tumors, fibrosis, cardiovascular and neurodegenerative diseases. Targeting the PDGF/PDGFR pathway is therefore a promising therapeutic strategy. At present, a variety of PDGF/PDGFR targeted drugs with potential therapeutic effects have been developed, mainly including PDGF agonists, inhibitors targeting PDGFR and proteolysis targeting chimera (PROTACs). This review clarifies the structure, biological function and disease correlation of PDGF and PDGFR, and it discusses the current status of PDGFR-targeted drugs, so as to provide a reference for subsequent research.

Simultaneous determination of 11 oral targeted antineoplastic drugs and 2 active metabolites by LC-MS/MS in human plasma and its application to therapeutic drug monitoring in cancer patients

Interindividual exposure differences have been identified in oral targeted antineoplastic drugs (OADs) owing to the pharmacogenetic background of the patients and their susceptibility to multiple factors, resulting in insufficient efficacy or adverse effects. Therapeutic drug monitoring (TDM) can prevent sub-optimal concentrations of OADs and improve their clinical treatment. This study aimed to develop and validate an LC-MS/MS method for the simultaneous quantification of 11 OADs (gefitinib, imatinib, lenvatinib, regorafenib, everolimus, osimertinib, sunitinib, tamoxifen, lapatinib, fruquintinib and sorafenib) and 2 active metabolites (N-desethyl sunitinib and Z-endoxifen) in human plasma. Protein precipitation was used to extract OADs from the plasma samples. Chromatographic separation was performed using an Eclipse XDB-C18 (4.6 × 150 mm, 5 μm) column with a gradient elution of the mobile phase composed of 2 mM ammonium acetate with 0.1 % formic acid in water (solvent A) and methanol (solvent B) at a flow rate of 0.8 mL/min. Mass analysis was performed using positive ion mode electrospray ionization in multiple-reaction monitoring mode. The developed method was validated following FDA bioanalytical guidelines. The calibration curves were linear over the range of 2-400 ng/mL for gefitinib, imatinib, lenvatinib, regorafenib, and everolimus; 1-200 ng/mL for osimertinib, sunitinib, N-desethyl sunitinib, tamoxifen, and Z-endoxifen; and 5-1000 ng/mL for lapatinib, fruquintinib, and sorafenib, with all coefficients of correlation above 0.99. The intra- and inter-day imprecision was below 12.81 %. This method was successfully applied to the routine TDM of gefitinib, lenvatinib, regorafenib, osimertinib, fruquintinib, and sorafenib to optimize the dosage regimens.

Sunitinib promotes apoptosis via p38 MAPK activation and STAT3 downregulation in oral keratinocytes

OBJECTIVE

Sunitinib, a targeted cancer drug, inhibits tyrosine kinases receptors and is widely used as first-line treatment for metastatic renal cell carcinoma. Patients undergoing chemotherapy with sunitinib frequently have oral mucosal complications, such as oral stomatitis, though cytotoxic effects of the drug on oral keratinocytes remain unknown.

METHODS

The effects of sunitinib on immortalized oral keratinocytes, RT7 cells, in regard to cell injury and apoptosis, as well as apoptosis-mediated signaling pathways were investigated.

RESULTS

Sunitinib treatment caused a significant increase in lactate dehydrogenase (LDH) in RT7 cells and primary oral keratinocytes. Additionally, the drug induced apoptosis-related events, such as DNA fragmentation, decreased anti-apoptotic Bcl-2 protein expression, and induction of cleaved PARP and caspase 3/9 in RT7 cells. Furthermore, phosphorylation of p38 MAPK, but not of ERK or JNK, was increased. On the contrary, constitutive phosphorylated STAT3 was decreased by sunitinib treatment, which was recovered by exposure to SB203580, a p38 MAPK inhibitor. Finally, SB203580 was found to reduce sunitinib-induced cell injury and apoptosis.

CONCLUSION

The present results indicate that sunitinib promotes cell injury and apoptosis in oral keratinocytes via p38 activation and STAT3 downregulation. Sunitinib-mediated oral complications may be associated with cytotoxic effects of the drug on oral keratinocytes.

Solitary Clear Cell Renal Cell Carcinoma Metastasis to the Eyelid: A Case Report

Introduction

This study is a case of solitary clear cell renal cell carcinoma (ccRCC) eyelid metastasis in a 66-year-old man as the first sign of a primary tumor. ccRCC usually spreads to the lungs, mediastinum, bones, liver, and brain, while ocular metastases are rare.

Case Presentation

Solitary metastasis presented as a solid mass in the central third of the upper eyelid, which has been growing for 3 weeks. Treatment included tumor removal and blepharoplasty. Histopathological examination showed metastasis of clear cell renal carcinoma. A thorough examination revealed a primary tumor on the lower pole of the right kidney. A right nephrectomy was performed, and histopathology showed ccRCC. Postoperative examinations showed no signs of local or systemic disease. Sunitinib malate was administered to the patient.

Conclusion

The eyelid metastasis in this case was still solitary and had been discovered before the existence of the primary tumor was known. Ocular metastasis of renal carcinoma is a rare initial manifestation of the disease and therefore requires a multidisciplinary approach in the treatment of these patients.

Pharmacokinetics and bioequivalence of sunitinib and Sutent® in Chinese healthy subjects: an open-label, randomized, crossover study

Purpose: The purpose of this study was to examine the pharmacokinetics (PK), bioequivalence and safety of generic sunitinib and its original product Sutent® in healthy Chinese subjects through a phase-I clinical trial. Methods: The study selected two groups of 24 healthy Chinese subjects in a 1:1 ratio through random allocation. Each participant received either 12.5 mg of sunitinib or Sutent® per cycle. A total of 15 different time points were employed for blood sample collection during each cycle. Furthermore, a comprehensive assessment of the drugs' safety was consistently maintained throughout the trial. Results: The average adjusted geometric mean ratios (GMR) (90% CI) for the primary PK parameters Cmax, AUC0-t and AUC0-∞ were 97.04% (93.06%-101.19%), 98.45% (93.27%-103.91%) and 98.22% (93.15%-103.56%), respectively. The adjusted GMRs for essential pharmacokinetic (PK) parameters all met the requirements for bioequivalence, with values within the acceptable range of 80%-125%. In addition, the two drugs showed comparable results for the other PK parameters. These results indicate that the two drugs were bioequivalent. Furthermore, both drugs showed well safety. Conclusion: The research results proved that the PK and safety profiles of sunitinib in healthy Chinese subjects were comparable to those of Sutent®. These results advocate the clinical application of generic sunitinib as a potential alternative to original product Sutent® in the treatment of certain medical conditions.

The effect of rifampin on the pharmacokinetics of famitinib in healthy subjects

Background

Famitinib is an oral, small-molecule, multi-targeted tyrosine kinase inhibitor under clinical investigation for the treatment of solid tumors. As famitinib is metabolized mainly by cytochrome P450 3A4 (CYP3A4), the study was conducted to investigate the effect of potent CYP3A4 inducer rifampin on the pharmacokinetics of famitinb.

Methods

This single-center, single-arm and fixed-sequence drug–drug interaction study enrolled 21healthy Chinese male subjects. Subjects received a single oral dose of famitinib 25 mg on days 1 and 16 and repeated administration of oral rifampin 600 mg once daily on days 10–23. Blood samples were collected and plasma concentrations of famitinib were measured by validated liquid chromatography-tandem mass spectrometry (LC–MS/MS) method. Pharmacokinetic parameters were calculated using noncompartmental analysis and safety was assessed.

Results

In the presence of rifampin, the famitinib geometric mean maximum plasma concentration (Cmax) and area under the plasma concentration–time curve from time zero to infinity (AUC0–∞) decreased by 48% and 69%, respectively, and the mean elimination half-life was shortened from 33.9 to 18.2 h. The geometric mean ratio (GMR) of famitinib Cmax and AUC0–∞ and their 90% CI were 0.52 (0.50, 0.54) and 0.31 (0.29, 0.33). Single dose of famitinib 25 mg was well tolerated and eight subjects (38.1%) reported treatment emergent adverse events, which were all grade 1–2 in severity.

Conclusion

Co-administration of rifampin considerably reduces plasma concentration of famitinb due to CYP3A4 induction. Concomitant administration of famitinib and strong CYP3A4 inducers should be avoided, whereas when simultaneous use with inducers of CYP3A4, dose adjustment of famitinb is recommended.

Clinical trial registration number

NCT04494659 (July 31, 2020).

Patient-Derived Organoid Facilitating Personalized Medicine in Gastrointestinal Stromal Tumor With Liver Metastasis: A Case Report

The gastrointestinal stromal tumors (GIST) are a rare gastrointestinal tract malignancy. The two primary mutation sites are found in KIT and platelet-derived growth factor receptor-α (PDGFR-α) genes. The current study reports on a point mutation within the exon 11 of KIT, named KIT p.V560E. Patient-derived organoids (PDOs) are potential 3D in vitro models of tissues that can be used to identify sensitivity toward specific targets in patients with tumors and allow for personalized medicine when drugs specific for newly identified genetic locus mutations are not yet available. This study describes a 68-year-old patient who complained of diffused abdominal pain and intermittent melena lasting more than 10 days. He has no other gastrointestinal abnormalities, prior abdominal surgery, or related family history. Surgery was conducted first to remove the lesions and ascertain the disease through histology and immunohistochemical stains of the mass. Immunohistochemistry revealed that the tumor was positive for CD117 and Dog-1. Based on the above findings, he was diagnosed with GISTs. Gene detection analysis and organoid culture were then performed to verify clinical decisions. KIT p.V560E and the reduced number of RB1 copies were identified as two obvious mutations, so the patient was administrated first-line treatment of imatinib 400 mg/d. However, progressive disease prompted us to switch to sunitinib, and his condition gradually improved. Meanwhile, organoid culture showed sensitivity to sunitinib and tolerance to imatinib with half-maximal inhibitory concentration (IC50) values of 0.89 and >20, respectively. In summary, to the best of our knowledge, this is the first time that the established organoid culture indicated that the GISTs organoid could identify the sensitivity to target therapies and facilitate individual-based treatment.

Dose Individualization of Oral Multi-Kinase Inhibitors for the Implementation of Therapeutic Drug Monitoring

Oral multi-kinase inhibitors have transformed the treatment landscape for various cancer types and provided significant improvements in clinical outcomes. These agents are mainly approved at fixed doses, but the large inter-individual variability in pharmacokinetics and pharmacodynamics (efficacy and safety) has been an unsolved clinical issue. For example, certain patients treated with oral multi-kinase inhibitors at standard doses have severe adverse effects and require dose reduction and discontinuation, yet other patients have a suboptimal response to these drugs. Consequently, optimizing the dosing of oral multi-kinase inhibitors is important to prevent over-dosing or under-dosing. To date, multiple studies on the exposure-efficacy/toxicity relationship of molecular targeted therapy have been attempted for the implementation of therapeutic drug monitoring (TDM) strategies. In this milieu, we recently conducted research on several multi-kinase inhibitors, such as sunitinib, pazopanib, sorafenib, and lenvatinib, with the aim to optimize their treatment efficacy using a pharmacokinetic/pharmacodynamic approach. Among them, sunitinib use is an example of successful TDM implementation. Sunitinib demonstrated a significant correlation between drug exposure and treatment efficacy or toxicities. As a result, TDM services for sunitinib has been covered by the National Health Insurance program in Japan since April 2018. Additionally, other multi-kinase targeted anticancer drugs have promising data regarding the exposure-efficacy/toxicity relationship, suggesting the possibility of personalization of drug dosage. In this review, we provide a comprehensive summary of the clinical evidence for dose individualization of multi-kinase inhibitors and discuss the utility of TDM of multi-kinase inhibitors, especially sunitinib, pazopanib, sorafenib, and lenvatinib.

Boosting the Anticancer Activity of Sunitinib Malate in Breast Cancer through Lipid Polymer Hybrid Nanoparticles Approach

In the current study, lipid-polymer hybrid nanoparticles (LPHNPs) fabricated with lipoid-90H and chitosan, sunitinib malate (SM), an anticancer drug was loaded using lecithin as a stabilizer by employing emulsion solvent evaporation technique. Four formulations (SLPN1-SLPN4) were developed by varying the concentration of chitosan polymer. Based on particle characterization, SLPN4 was optimized with size (439 ± 5.8 nm), PDI (0.269), ZP (+34 ± 5.3 mV), and EE (83.03 ± 4.9%). Further, the optimized formulation was characterized by FTIR, DSC, XRD, SEM, and in vitro release studies. In-vitro release of the drug from SPN4 was found to be 84.11 ± 2.54% as compared with pure drug SM 24.13 ± 2.67%; in 48 h, release kinetics followed the Korsmeyer-Peppas model with Fickian release mechanism. The SLPN4 exhibited a potent cytotoxicity against MCF-7 breast cancer, as evident by caspase 3, 9, and p53 activities. According to the findings, SM-loaded LPHNPs might be a promising therapy option for breast cancer.

Quantitative and qualitative changes in platelet traits of sunitinib-treated patients with renal cell carcinoma in relation to circulating sunitinib levels: a proof-of-concept study

Background

Tyrosine kinase inhibitors (TKIs), such as sunitinib, are used for cancer treatment, but may also affect platelet count and function with possible hemostatic consequences. Here, we investigated whether patient treatment with the TKI sunitinib affected quantitative and qualitative platelet traits as a function of the sunitinib level and the occurrence of bleeding.

Methods

Blood was collected from 20 metastatic renal cell carcinoma (mRCC) patients before treatment, and at 2 weeks, 4 weeks and 3 months after sunitinib administration. We measured blood cell counts, platelet aggregation, and concentrations of sunitinib as well as its N-desethyl metabolite in plasma, serum and isolated platelets. Progression of disease (PD) and bleeding were monitored after 3 months.

Results

In sunitinib-treated mRCC patients, concentrations of (N-desethyl-)sunitinib in plasma and serum were highly correlated. In the patients’ platelets the active metabolite levels were relatively increased as compared to sunitinib. On average, a sustained reduction in platelet count was observed on-treatment, which was significantly related to the inhibitor levels in plasma/serum. Principal component and correlational analysis showed that the (N-desethyl-)sunitinib levels in plasma/serum were linked to a reduction in both platelet count and collagen-induced platelet aggregation. The reduced aggregation associated in part with reported bleeding, but did not correlate to PD.

Conclusion

The sunitinib-induced reduction in quantitative and qualitative platelet traits may reflect the effective sunitinib levels in the patient. These novel results may serve as a proof-of-principle for other TKI-related drugs, where both platelet count and functions are affected, which could be used for therapeutic drug monitoring.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09676-0.

Treatment of Gastrointestinal Stromal Tumors (GISTs): A Focus on Younger Patients

Gastrointestinal stromal tumors (GISTs) originate from Cajal's cells and are the most common mesenchymal neoplasms of the gastrointestinal tract. GISTs in young adults, i.e., patients before the age of 40, are rare and differ from those in older patients and GISTs in children in terms of the molecular and clinical features, including the location and type of mutations. They often harbor other molecular abnormalities than KIT and PDGFRA mutations (wild-type GISTs). The general principles of therapeutic management in young patients are the same as in the elderly. Considering some differences in molecular abnormalities, molecular testing should be the standard procedure to allow appropriate systemic therapy if needed. The optimal treatment strategy should be established by a multidisciplinary team experienced in sarcoma treatment. The impact of treatment on the quality of life and daily activities, including the impact on work, pregnancy, and fertility, in this patient population should be especially taken into consideration.

Overcome Drug Resistance in Cholangiocarcinoma: New Insight Into Mechanisms and Refining the Preclinical Experiment Models

Cholangiocarcinoma (CCA) is an aggressive tumor characterized by a poor prognosis. Therapeutic options are limited in patients with advanced stage of CCA, as a result of the intrinsic or acquired resistance to currently available chemotherapeutic agents, and the lack of new drugs entering into clinical application. The challenge in translating basic research to the clinical setting, caused by preclinical models not being able to recapitulate the tumor characteristics of the patient, seems to be an important reason for the lack of effective and specific therapies for CCA. So, there seems to be two ways to improve patient outcomes. The first one is developing the combination therapies based on a better understanding of the mechanisms contributing to the resistance to currently available chemotherapeutic agents. The second one is developing novel preclinical experimental models that better recapitulate the genetic and histopathological features of the primary tumor, facilitating the screening of new drugs for CCA patients. In this review, we discussed the evidence implicating the mechanisms underlying treatment resistance to currently investigated drugs, and the development of preclinical experiment models for CCA.

Assessment of the Effects of Inhibition or Induction of CYP2C19 and CYP2C9 Enzymes, or Inhibition of OAT3, on the Pharmacokinetics of Abrocitinib and Its Metabolites in Healthy Individuals

Background and Objective

Abrocitinib is a Janus kinase 1-selective inhibitor for the treatment of moderate-to-severe atopic dermatitis. Abrocitinib is eliminated primarily by metabolism involving cytochrome P450 (CYP) enzymes. Abrocitinib pharmacologic activity is attributable to the unbound concentrations of the parent molecule and 2 active metabolites, which are substrates of organic anion transporter 3 (OAT3). The sum of potency-adjusted unbound exposures of abrocitinib and its 2 active metabolites is termed the abrocitinib active moiety. We evaluated effects of CYP inhibition, CYP induction, and OAT3 inhibition on the pharmacokinetics of abrocitinib, its metabolites, and active moiety.

Methods

Three fixed-sequence, open-label, phase I studies in healthy adult volunteers examined the drug–drug interactions (DDIs) of oral abrocitinib with fluvoxamine and fluconazole, rifampin, and probenecid.

Results

Co-administration of abrocitinib with fluvoxamine or fluconazole increased the area under the plasma concentration–time curve from time 0 to infinity (AUC_inf) of the unbound active moiety of abrocitinib by 91% and 155%, respectively. Co-administration with rifampin decreased the unbound active moiety AUC_inf by 56%. The OAT3 inhibitor probenecid increased the AUC_inf of the unbound active moiety by 66%.

Conclusions

It is important to consider the effects of DDIs on the abrocitinib active moiety when making dosing recommendations. Co-administration of strong CYP2C19/2C9 inhibitors or CYP inducers impacted exposure to the abrocitinib active moiety. A dose reduction by half is recommended if abrocitinib is co-administered with strong CYP2C19 inhibitors, whereas co-administration with strong CYP2C19/2C9 inducers is not recommended. No dose adjustment is required when abrocitinib is administered with OAT3 inhibitors.

Clinical Trials Registration IDs

NCT03634345, NCT03637790, NCT03937258

Supplementary Information

The online version contains supplementary material available at 10.1007/s13318-021-00745-6.

The role of diet in renal cell carcinoma incidence: an umbrella review of meta-analyses of observational studies

BACKGROUND

Evidence associating diet with the incidence of renal cell carcinoma (RCC) is inconclusive. We aimed to summarize evidence associating dietary factors with RCC incidence and assess the strength and validity of this evidence.

METHODS

We conducted an umbrella review of systematic reviews or meta-analyses (SRoMAs) that assessed the association between diet and RCC incidence. Through April 2021, PubMed, Web of Science, Embase, The Cochrane Library, Scopus, and WCRF were searched. Two independent reviewers selected studies, extracted data, and appraised the quality of SRoMAs. According to credibility assessment criteria, evidence can be divided into five categories: convincing (class I), highly suggestive (class II), suggestive (class III), weak (class IV), and nonsignificant (class V).

RESULTS

Twenty-nine meta-analyses were obtained after screening. After excluding 7 overlapping meta-analyses, 22 meta-analyses including 502 individual studies and 64 summary hazard ratios for RCC incidence were included: dietary patterns or dietary quality indices (n = 6), foods (n = 13), beverages (n = 4), alcohol (n = 7), macronutrients (n =15), and micronutrients (n =19). No meta-analyses had high methodological quality. Five meta-analyses exhibited small study effects; one meta-analysis showed evidence of excess significance bias. No dietary factors showed convincing or highly suggestive evidence of association with RCC in the overall analysis. Two protective factors had suggestive evidence (vegetables (0.74, 95% confidence interval 0.63 to 0.86) and vitamin C (0.77, 0.66 to 0.90)) in overall analysis. One protective factor had convincing evidence (moderate drinking (0.77, 0.70 to 0.84)) in Europe and North America and one protective factor had highly suggestive evidence (cruciferous vegetables (0.78, 0.70 to 0.86)) in North America.

CONCLUSIONS

Although many meta-analyses have assessed associations between dietary factors and RCC, no high-quality evidence exists (classes I and II) in the overall analysis. Increased intake of vegetables and vitamin C is negatively associated with RCC risk. Moderate drinking might be beneficial for Europeans and North Americans, and cruciferous vegetables might be beneficial to North Americans, but the results should be interpreted with caution. More researches are needed in the future.

TRIAL REGISTRATION

PROSPERO CRD42021246619.

Discrimination of hand-foot skin reaction caused by tyrosine kinase inhibitors based on direct keratinocyte toxicity and vascular endothelial growth factor receptor-2 inhibition

Tyrosine kinase inhibitors (TKIs) are molecular-targeted anticancer drugs. Their benefits are limited by dermal toxicities, including hand-foot skin reaction (HFSR), which is commonly found in skin areas subjected to friction. The present study aimed to explain the incidence of HFSR in patients treated with TKIs by focusing on keratinocyte toxicity and inhibition of vascular endothelial growth factor receptor (VEGFR), which plays an essential role in angiogenesis. Mice with gene knockout for the immunosuppressive cytokine interleukin-10 exhibited HFSR-like phenotypes, such as cytotoxicity in keratinocytes and increased number and size of blood vessels after repeated doses of regorafenib, sorafenib, and pazopanib, all of which cause high incidence of HFSR, in combination with tape-stripping mimicking skin damage at the friction site. Comprehensive examination of the direct cytotoxic effects of 21 TKIs on primary cultured human keratinocytes revealed that 18 of them reduced the cell viability dose-dependently. Importantly, the ratio of the trough concentration in patients (C_trough) to the LC₅₀ values of cell viability reduction was higher than unity for four HFSR-inducing TKIs, suggesting that these TKIs cause keratinocyte toxicity at clinically relevant concentrations. In addition, eight HFSR-inducing TKIs caused inhibition of VEGFR-2 kinase activity, which was validated by their ratios of C_trough to the obtained IC_50,VEGFR-2 of more than unity. All 12 TKIs with no reported incidence of HFSR exhibited less than unity values for both C_trough/LC_{50,keratinocytes} and C_trough/IC_50,VEGFR-2. These results suggested that a combination of keratinocyte toxicity and VEGFR-2 inhibition may explain the incidence of HFSR upon TKI usage in humans.

Investigation of temperature-responsive tocosomal nanocarriers as the efficient and robust drug delivery system for Sunitinib malate anti-cancer drug: Effects of MW and chain length of PNIPAAm on LCST and dissolution rate

In this study, for the first time, the coated tocosome by blend of chitosan, CS, and poly(N-isopropylacrylamide), PNIPAAm, was developed as the efficient and robust drug delivery system with improved drug encapsulation efficiency, extended stability, proper particle size and industrial upscaling for Sunitinib malate anti-cancer drug. Tocosome was synthesized by using Mozafari method as a scalable and robust method and without the need for organic solvents. The effects of tocosome composition and drug concentration on the stability, particle size of tocosome, zeta potential, encapsulation efficacy and loading of drug into it were investigated by Taguchi method, and optimum composition was selected for combining with the polymeric blend. Homopolymer of PNIPAAm was synthesized by two different polymerization methods, including free radical and reversible addition-fragmentation chain transfer (RAFT). Effects of molecular weight (MW) and chain length of the polymers on lower critical solution temperature (LCST) were examined. The developed nanocarrier in this research, CS-Raft-PNIPAAm-tocosome, indicated LCST value beyond 37°C (about 45°C) and this is suitable for hyperthermia and spatio-temporal release of drug particles.

Effective Antiviral Activity of the Tyrosine Kinase Inhibitor Sunitinib Malate against Zika Virus

Introduction

Zika virus (ZIKV), a mosquito-borne flavivirus, causes the outbreaks of Latin America in 2015 - 2016, with the incidence of neurological complications. Sunitinib malate, an orally bioavailable malate salt of the tyrosine kinase inhibitor, is suggested as a broad-spectrum antiviral agent against emerging viruses like severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2.

Materials and Methods

This study investigated the antiviral efficacy and antiviral mechanisms of sunitinib malate against ZIKV infection using cytopathic effect reduction, virus yield, and time-of-addition assays.

Results

Sunitinib malate concentration-dependently reduced ZIKV-induced cytopathic effect, the expression of viral proteins, and ZIKV yield in supernatant with 50% inhibitory concentration (IC₅₀) value of 0.015 μM, and the selectivity index of greater than 100 against ZIKV infection, respectively. Sunitinib malate had multiple antiviral actions during entry and post-entry stages of ZIKV replication. Sunitinib malate treatment at entry stage significantly reduced the levels of ZIKV RNA replication with the reduction of (+) RNA to (-) RNA ratio and the production of new intracellular infectious particles in infected cells. The treatment at post-entry stage caused a concentration-dependent increase in the levels of ZIKV (+) RNA and (-) RNA in infected cells, along with enlarging the ratio of (+) RNA to (-) RNA, but caused a pointed increase in the titer of intracellular infectious particles by 0.01 and 0.1 μM, and a substantial decrease in the titer of intracellular infectious particles by 1 μM.

Conclusion

The study discovered the antiviral actions of sunitinib malate against ZIKV infection, demonstrating a repurposed, host-targeted approach to identify potential antiviral drugs for treating emerging and global viral diseases.

Balancing the Risk-Benefit Ratio of Immune Checkpoint Inhibitor and Anti-VEGF Combination Therapy in Renal Cell Carcinoma: A Systematic Review and Meta-Analysis

Background

Although immune checkpoint inhibitors (ICIs) combined with vascular endothelial growth factor receptor (VEGFR)-targeted therapy and sunitinib monotherapy have been widely applied to metastatic renal cell carcinoma (mRCC), effectiveness and safety data are still lacking. To optimize clinical decision-making, we conducted a systematic review and meta-analysis of published randomized clinical trials to characterize the efficacy and the risk of adverse events (AEs) in patients treated with ICIs plus anti-VEGF therapy.

Materials and Methods

We used PubMed, EMBASE, and the Cochrane Library to retrieve randomized controlled trials (RCTs) published before March 27, 2021. The efficacy outcomes were progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). The pooled risk ratio (RR) and 95% confidence intervals (CI) of AEs were calculated in the safety analysis.

Results

Six RCTs involving 4,227 patients were identified after a systematic search. For OS, ICI and anti-VEGF combination therapy decreased mortality approximately 30% in the intention-to-treat population (ITT) (hazard ratio (HR) = 0.70, 95% CI: 0.57–0.87), but there was no statistical difference in patients evaluated as “favorable” by the International Metastatic Renal-Cell Carcinoma Database Consortium (IMDC) criteria compared with monotherapy (HR = 0.90, 95% CI: 0.55–1.46, p = 0.66). In terms of PFS, the progression risk for all participants declined 35% (HR = 0.65, 95% CI: 0.50–0.83) and patients evaluated as “poor” by IMDC benefited further (HR = 0.46, 95% CI: 0.36–0.58). No evident divergence was found in age and sex subgroups. The RRs of all-grade hypertension, arthralgia, rash, proteinuria, high-grade (grades 3–5) arthralgia, and proteinuria developed after combination therapy were increased compared with sunitinib. The risk of high-grade hypertension and rash showed no statistical difference. However, the risk of hand-foot skin reaction (HFSR), stomatitis, and dysgeusia decreased in combination therapy groups.

Conclusions

Compared with sunitinib, OS, PFS, and ORR were significantly improved in patients receiving ICI and anti-VEGF combination therapy at the expense of increased specific AEs. More attention should be paid to individualized application of these combination therapies to achieve the best benefit-risk ratio in the clinic.

Systematic Review Registration

[https://inplasy.com/] INPLASY: 202130104.

Tyrosine kinase inhibitors as next generation oncological therapeutics: Current strategies, limitations and future perspectives

Protein kinases, a class of enzymes that govern various biological phenomena at a cellular level, are responsible for signal transduction in cells that regulate cellular proliferation, differentiation, and growth. Protein kinase enzyme mutation results in abnormal cell division leading to a pathological condition like cancer. Tyrosine kinase (TK) inhibitors, which helps as a potential drug candidate for the treatment of cancer, are continuously being developed. Majority of these drug candidates are being administered as conventional oral dosage form, which provides limited safety and efficacy due to non-specific delivery and uncontrolled biodistribution resulting into the adverse effects. A controlled drug delivery approach for the delivery of TK inhibitors may be a potential strategy with significant safety and efficacy profile. Novel drug delivery strategies provide target-specific drug delivery, improved pharmacokinetic behaviour, and sustained release leading to lower doses and dosing frequency with significantly reduced side effects. Along with basic aspects of tyrosine kinase, this review discusses various aspects related to the application of tyrosine kinase inhibitors in clinical oncological setting. Furthermore, the limitations/challenges and formulation advancements related to this class of candidates particularly for cancer management have been reviewed. It is expected that innovations in drug delivery approaches for TK inhibitors using novel techniques will surely provide a new insights for improved cancer treatment and patients' life quality.

Development of a Competitive Enzyme-Linked Immunosorbent Assay for the Determination of Sunitinib Unaffected by Light-Induced Isomerization

Sunitinib is an oral multi-targeted tyrosine kinase inhibitor approved for treating metastatic renal cell carcinoma. This study reports a specific and sensitive competitive enzyme-linked immunosorbent assay (ELISA) for the pharmacokinetic evaluation of sunitinib. Anti-sunitinib serum was obtained from mice by using N-(2-(diethylamino)ethyl)-5-formyl-2,4-dimethyl-1H-pyrrole-3-carboxamide (DFPC) as a hapten, which has the same substructure as sunitinib, in order to avoid the effects of structural changes in the geometrical isomers of sunitinib. Enzyme labeling of sunitinib with horseradish peroxidase was similarly performed using DFPC. Serum sunitinib concentrations below the limit of quantification of 0.52 ng/mL were reproducibly measurable. This ELISA was specific for sunitinib (Z- and E-isomers) and showed very low cross-reactivity (0.094%) with its major metabolite, N-desethyl sunitinib. Its analytical applicability was demonstrated by a kinetic study with human liver microsomes. In addition, the levels of sunitinib measured by ELISA in a kinetic study with human liver microsomes were comparable with those measured by HPLC, and there was a strong correlation between the values determined by both methods (y = 1.065x - 51.2, R² = 0.9804). The developed ELISA provides for the specific and sensitive quantification of sunitinib without the influence of its major metabolite or light-induced geometric isomers. This ELISA will be a valuable tool in pharmacokinetic studies of sunitinib.

Early Predictive Response to Multi-Tyrosine Kinase Inhibitors in Advanced Refractory Radioactive-Iodine Differentiated Thyroid Cancer: A New Challenge for [18F]FDG PET/CT

Differentiated thyroid cancer (DTC) represents the most common thyroid cancer histotype. Generally, it exhibits a good prognosis after conventional treatments; nevertheless, about 20% of patients can develop a local recurrence and/or distant metastasis. In one-third of advanced DTC, the metastatic lesions lose the ability to take up iodine and become radioactive iodine-refractory (RAI-R) DTC. In this set of patients, the possibility to perform localized treatments should always be taken into consideration before the initiation of systemic therapy. In the last decade, some multi-tyrosine kinase inhibitor (MKI) drugs were approved for advanced DTC, impacting on patient’s survival rate, but at the same time, these therapies have been associated with several adverse events. In this clinical context, the role of 2-deoxy-2-[¹⁸F]fluoro-D-glucose positron emission tomography/computed tomography ([¹⁸F]FDG PET/CT) in the early treatment response to these innovative therapies was investigated, in order to assess the potentiality of this diagnostic tool in the early recognition of non-responders, avoiding unnecessary therapy. Herein, we aimed to present a critical overview about the reliability of [¹⁸F]FDG PET/CT in the early predictive response to MKIs in advanced differentiated thyroid cancer.

Tyrosine Kinase Inhibitor Sunitinib Delays Platelet-Induced Coagulation: Additive Effects of Aspirin

BACKGROUND

 Sunitinib is a multitarget tyrosine kinase inhibitor (TKI) used for cancer treatment. In platelets, sunitinib affects collagen-induced activation under noncoagulating conditions. We investigated (1) the effects of sunitinib on thrombus formation induced by other TK-dependent receptors, and (2) the effects under coagulating conditions. Cardiovascular disease is a comorbidity in cancer patients, resulting in possible aspirin treatment. Sunitinib and aspirin are associated with increased bleeding risk, and therefore we also investigated (3) the synergistic effects of these compounds on thrombus and fibrin formation.

METHODS

 Blood or isolated platelets from healthy volunteers or cancer patients were incubated with sunitinib and/or aspirin or vehicle. Platelet activation was determined by TK phosphorylation, flow cytometry, changes in [Ca²⁺]_i, aggregometry, and whole blood perfusion over multiple surfaces, including collagen with(out) tissue factor (TF) was performed.

RESULTS

 Sunitinib reduced thrombus formation and phosphatidylserine (PS) exposure under flow on collagen type I and III. Also, sunitinib inhibited glycoprotein VI-induced TK phosphorylation and Ca²⁺ elevation. Upon TF-triggered coagulation, sunitinib decreased PS exposure and fibrin formation. In blood from cancer patients more pronounced effects of sunitinib were observed in lung and pancreatic as compared to neuroglioblastoma and other cancer types. Compared to sunitinib alone, sunitinib plus aspirin further reduced platelet aggregation, thrombus formation, and PS exposure on collagen under flow with(out) coagulation.

CONCLUSION

 Sunitinib suppresses collagen-induced procoagulant activity and delays fibrin formation, which was aggravated by aspirin. Therefore, we urge for awareness of the combined antiplatelet effects of TKIs with aspirin, as this may result in increased risk of bleeding.

Insight on a new indolinone derivative as an orally bioavailable lead compound against renal cell carcinoma

A series of novel 3-indolinone-thiazolidinones and oxazolidinones 4a-k was synthesized via molecular hybridization approach and sequentially evaluated to explore its cytotoxic activity. The cytotoxicity screening pointed toward the N-cyclohexyl thiazolidinone derivative 4f that revealed promising renal cytotoxicity against CAKI-1 and UO-31 renal cancer cell lines with IC₅₀ values 4.74 and 3.99 µM, respectively, which were comparable to those of sunitinib along with good safety threshold against normal renal cells. Further emphasis on compound 4f renal cytotoxicity was achieved via different enzyme assays and CAKI-1 and UO-31 cell cycle analysis. The results were supported by in silico studies to explore its physicochemical, pharmacokinetic and drug-likeness properties. Finally, compound 4f was subjected to an in vivo pharmacokinetic study through two different routes of administration showing excellent oral bioavailability. This research represents compound 4f as a promising candidate against renal cell carcinoma.

Treatment of Metastatic Gastrointestinal Stromal Tumors (GIST): A Focus on Older Patients

Gastrointestinal stromal tumors (GIST) originating in the Cajal cells are the most common mesenchymal neoplasms of the gastrointestinal tract. The median age of patients with this diagnosis is 65 years, and over 20% of cases affect people over the age of 70 years. The effectiveness and tolerability of systemic treatment with tyrosine kinase inhibitors in older patients with GIST seem to be similar to that in younger patients, but some studies have shown that treatment of older patients is suboptimal. Disability, frailty, comorbidities, and concomitant medications may influence treatment decisions, and toxicities also more often lead to treatment discontinuation. The known safety profile and oral administration route of the tyrosine kinase inhibitors used in GIST may allow maximization of treatment and the best efficacy, especially in older patients. This review summarizes the efficacy data for the systemic treatment of GIST, including data for older patients and from real-world experiences, if available and significant. The reported safety data and general rules for toxicity management, including appropriate patient selection and the need for careful monitoring during treatment, are also discussed.

Acute sunitinib neurotoxicity

Sunitinib malate is a multitargeted oral tyrosine kinase inhibitor (TKI) which is used in treatment of metastatic renal cell carcinoma with side effects such as diarrhea, mucositis, asthenia and myelosuppression. Serious toxicity associated with sunitinib is a rare situation. However; there are few cases reported in the literature. As a result of the inhibition that is caused by sunitinib malate agent at the receptor level, vascular endothelial growth factor (VEGF) level increases. These increased VEGF levels are considered to having a positive contribution on neurological side effects. Neurotoxicity that is related with the usage of sunitinib malate for two weeks will be presented in this case report.

Sunitinib-associated hyperammonemic encephalopathy successfully managed with higher intensity conventional hemodialysis: A case report

RATIONALE

Hyperammonemia encephalopathy is a rare but severe complication that has been reported in association with the use of sunitinib, a tyrosine kinase inhibitor. We report here a unique case of a patient with end stage renal disease that was initiated on sunitinib for metastatic renal cell carcinoma.

PATIENT CONCERNS

A 65-year-old man with end stage renal disease on maintenance conventional hemodialysis and had concomitant stable Child-Pugh class B liver cirrhosis consequent of hepatitis C infection was started on sunitinib for metastatic renal cell carcinoma. He developed confusion few weeks after starting therapy with no other indication of worsening liver dysfunction otherwise.

DIAGNOSIS

He was later diagnosed with hyperammonemia encephalopathy.

INTERVENTIONS

His treatment was discontinued and reinitiated at a lower dose after recovery and titrated according to tolerance. As ammonia is a very low molecular weight molecule and is cleared well with diffusive clearance, we intensified his dialysis regimen by increasing intensity for each session and frequency per week.

OUTCOMES

With this change in dialysis regimen, patient was able to continue treatment with sunitinib.

LESSONS

Clinicians prescribing sunitinib should be vigilant to monitor for this complication in patients receiving sunitinib, apart from the more usual presentation of hepatotoxicity. We found that a more intensive hemodialysis regimen consisting of 4× a week conventional high-flux hemodialysis (HD) can permit the continuation of treatment with sunitinib in an end stage renal disease (ESRD) patient with Child-Pugh class B liver cirrhosis.

Structural Basis for Vascular Endothelial Growth Factor Receptor Activation and Implications for Disease Therapy

Vascular endothelial growth factors (VEGFs) bind to membrane receptors on a wide variety of cells to regulate diverse biological responses. The VEGF-A family member promotes vasculogenesis and angiogenesis, processes which are essential for vascular development and physiology. As angiogenesis can be subverted in many disease states, including tumour development and progression, there is much interest in understanding the mechanistic basis for how VEGF-A regulates cell and tissue function. VEGF-A binds with high affinity to two VEGF receptor tyrosine kinases (VEGFR1, VEGFR2) and with lower affinity to co-receptors called neuropilin-1 and neuropilin-2 (NRP1, NRP2). Here, we use a structural viewpoint to summarise our current knowledge of VEGF-VEGFR activation and signal transduction. As targeting VEGF-VEGFR activation holds much therapeutic promise, we examine the structural basis for anti-angiogenic therapy using small-molecule compounds such as tyrosine kinase inhibitors that block VEGFR activation and downstream signalling. This review provides a rational basis towards reconciling VEGF and VEGFR structure and function in developing new therapeutics for a diverse range of ailments.

Molecular targets of tyrosine kinase inhibitors in thyroid cancer

Thyroid cancer (TC) is the eighth most frequently diagnosed cancer worldwide with a rising incidence in the past 20 years. Surgery is the primary strategy of therapy for patients with medullary TC (MTC) and differentiated TC (DTC). In DTC patients, radioactive iodine (RAI) is administered after thyroidectomy. Neck ultrasound, basal and thyroid-stimulating hormone-stimulated thyroglobulin are generally performed every three to six months for the first year, with subsequent intervals depending on initial risk assessment, for the detection of possible persistent/recurrent disease during the follow up. Distant metastases are present at the diagnosis in ∼5 % of DTC patients; up to 15 % of patients have recurrences during the follow up, with a survival reduction (70 %-50 %) at 10-year. During tumor progression, the iodide uptake capability of DTC cancer cells can be lost, making them refractory to RAI, with a negative impact on the prognosis. Significant advances have been done recently in our understanding of the molecular pathways implicated in the progression of TCs. Several drugs have been developed, which inhibit signaling kinases or oncogenic kinases (BRAF^V600E, RET/PTC), such as those associated with Platelet-Derived Growth Factor Receptor and Vascular Endothelial Growth Factor Receptor. Tyrosine kinase receptors are involved in cancer cell proliferation, angiogenesis, and lymphangiogenesis. Several tyrosine kinase inhibitors (TKIs) are emerging as new treatments for DTC, MTC and anaplastic TC (ATC), and can induce a clinical response and stabilize the disease. Lenvatinib and sorafenib reached the approval for RAI-refractory DTC, whereas cabozantinib and vandetanib for MTC. These TKIs extend median progression-free survival, but do not increase the overall survival. Severe side effects and drug resistance can develop in TC patients treated with TKIs. Additional studies are needed to identify a potential effective targeted therapy for aggressive TCs, according to their molecular characterization.

Evaluation of NMU-Induced Breast Cancer Treated with Sirolimus and Sunitinib on Breast Cancer Growth

Objective:

To analyze the effect of sirolimus and sunitinib in blocking the tumor growth and to evaluate the expressions of estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor-2 (HER2/neu) after treated with sirolimus and sunitinib.

Methods:

Thirty-two female Sprague Dawley rats at age 21-days old were administered intraperitoneally with N-Methyl-N-Nitroso Urea (NMU), dosed at 70mg/kg body weight. The rats were divided into 4 groups; Group 1 (Control, n=8), Group 2 (Sirolimus, n=8), Group 3 (Sunitinib, n=8) and Group 4 (Sirolimus+Sunitinib, n=8), being treated twice when the tumor reached the size of 14.5±0.5 mm and subsequently sacrificed after 5 days. The protein expressions of ER, PgR and HER2/neu of the tumor tissues were evaluated by using immunohistochemistry analysis.

Results:

Treatment with sirolimus alone lowered expressions of ER and PgR of breast cancer and reduced tumor size. There was no significant difference of ER and PgR expressions between control and sunitinib treated tumor. Sunitinib treated tumors reduce in diameter after the first treatment, however the diameter increases after the second treatment. Histologically, sunitinib treated tumor did not show any aggressive invasive carcinoma of no special type (NST) histological subtypes. In addition, all NMU-induced tumors are HER2/neu-negative scoring.

Conclusion:

Sirolimus is neither synergistic nor additive with sunitinib for breast cancer treatment.

ePAD: An Image Annotation and Analysis Platform for Quantitative Imaging

Medical imaging is critical for assessing the response of patients to new cancer therapies. Quantitative lesion assessment on images is time-consuming, and adopting new promising quantitative imaging biomarkers of response in clinical trials is challenging. The electronic Physician Annotation Device (ePAD) is a freely available web-based zero-footprint software application for viewing, annotation, and quantitative analysis of radiology images designed to meet the challenges of quantitative evaluation of cancer lesions. For imaging researchers, ePAD calculates a variety of quantitative imaging biomarkers that they can analyze and compare in ePAD to identify potential candidates as surrogate endpoints in clinical trials. For clinicians, ePAD provides clinical decision support tools for evaluating cancer response through reports summarizing changes in tumor burden based on different imaging biomarkers. As a workflow management and study oversight tool, ePAD lets clinical trial project administrators create worklists for users and oversee the progress of annotations created by research groups. To support interoperability of image annotations, ePAD writes all image annotations and results of quantitative imaging analyses in standardized file formats, and it supports migration of annotations from various propriety formats. ePAD also provides a plugin architecture supporting MATLAB server-side modules in addition to client-side plugins, permitting the community to extend the ePAD platform in various ways for new cancer use cases. We present an overview of ePAD as a platform for medical image annotation and quantitative analysis. We also discuss use cases and collaborations with different groups in the Quantitative Imaging Network and future directions.

An HPLC method for simultaneous quantification of sunitinib and its active metabolite, SU12662, using hydrophilic interaction chromatography principle

Aim: To develop a sensitive HPLC method for the quantitation of sunitinib (SU) and its active metabolite N-desethyl-sunitinib (SU12662) in human plasma. Materials & methods: The analytes were extracted from 500 μl of plasma using liquid–liquid extraction followed by protein precipitation. Chromatographic separation of two analytes and internal standard, vandetenib, was achieved on a hydrophilic interaction liquid chromatography analytical column using a gradient program. Calibration curves were linear over the range of 10–250 ng/ml for both SU and SU12662. The method was validated according to the US FDA guidelines for bioanalytical methods. Accuracy of the method at 10 ng/ml for SU and SU12662 was 8.7 and 6.7%, respectively, and precision was 10.18% and 17.3%, respectively. Conclusion: This method allows a specific, sensitive and reliable determination of SU and SU12662 in human plasma in a single analytical run which makes it useful for therapeutic drug monitoring.

A new high-performance liquid chromatography-tandem mass spectrometry method for the determination of sunitinib and N-desethyl sunitinib in human plasma: Light-induced isomerism overtaking towards therapeutic drug monitoring in clinical routine

Sunitinib is approved for advanced renal cell cancer, imatinib-resistant or -intolerant gastrointestinal stromal tumors and pancreatic neuroendocrine cancers. It is prescribed at a fixed dose but its plasma exposure shows large inter-individual variations. Taking into account the narrow therapeutic window and the positive exposure-efficacy relationship, there is a robust rationale for its therapeutic drug monitoring. In fact, a target plasma concentration of sunitinib plus its active metabolite, N-desethyl sunitinib, ≥50 ng/mL was suggested. In order to quantify sunitinib and N-desethyl sunitinib in patients' plasma, we developed and validated a new LC-MS/MS method applicable to clinical routine. In solution, sunitinib and N-desethyl sunitinib undergo to photo-isomerization and many published methods overcome this problem by conducting the entire procedures of samples collection and handling under strictly light-protection. Our method is based on a simple and fast procedure that quantitatively reconverts the E-isomer of both analytes, obtained during sample draw and processing without light-protection, into their Z-forms. Moreover, our method uses a small plasma volume (30 μL) and the analytes are extracted by a rapid protein precipitation. It was validated according to EMA-FDA guidelines. The calibration curves resulted linear (R² always >0.993) over the concentration ranges (0.1-500 ng/mL for sunitinib, 0.1-250 ng/mL for N-desethyl sunitinib) with a good precision (within 7.7 % for sunitinib and 10.8% for N- desethyl sunitinib) and accuracy (range 95.8-102.9% for sunitinib and 92.3-106.2% for N-desethyl sunitinib). This method was applied to a pharmacokinetic study in one patient treated with sunitinib. Moreover, as incurred samples reanalysis is an established part of the bioanalytical process to support clinical studies, its assessment was performed early in order to assure that any reproducibility issues was detected as soon as possible. The percentage difference between the two runs resulted within ±20% in all the re-analysed samples for both sunitinib and N- desethyl sunitinib.

Nilotinib induction of melanogenesis via reactive oxygen species-dependent JNK activation in B16F0 mouse melanoma cells

Nilotinib (AMN), a second-generation tyrosine kinase inhibitor, induces apoptosis in various cancer cells, and our recent study showed that AMN effectively reduced the viability of human ovarian cancer cells via mitochondrion-dependent apoptosis. The effect of AMN in the melanogenesis of melanoma cells is still unclear. In the present study, we found that the addition of AMN but not imatinib (STI) significantly increased the darkness of B16F0 melanoma cells, and the absorptive value increased with the concentration of AMN. A decrease in the viability of B16F0 cells by AMN was detected in a concentration-dependent manner, accompanied by increased DNA ladders, hypodiploid cells and cleavage of the caspase-3 protein. An in vitro tyrosinase (TYR) activity assay showed that increased TYR activity by AMN was detected in a concentration-dependent manner; however, induction of TYR activity by STI at a concentration of 40 μmol/L was observed. Increased intracellular peroxide by AMN was detected in B16F0 cells, and application of the antioxidant, N-acetylcysteine (NAC), significantly reduced AMN-induced peroxide production which also reduced the darkness of B16F0 cells. Additionally, AMN induced c-Jun N-terminal kinase (JNK) protein phosphorylation in B16F0 cells, which was inhibited by the addition of NAC. AMN-induced melanogenesis of B16F0 cells was significantly inhibited by the addition of NAC and the JNK inhibitor, SP600125 (SP). Data of Western blotting showed that increased protein levels of melanogenesis-related enzymes of tyrosinase-related protein-1 (TRP1), TRP2 and TYR were observed in AMN-treated B16F0 cells which were inhibited by the addition of NAC and SP. Evidence is provided supporting AMN effectively inducing the melanogenesis of B16F0 melanoma cells via reactive oxygen species-dependent JNK activation.

Correlations between quantitative parameters of contrast-enhanced ultrasound and vasculogenic mimicry in murine tumor model: a novel noninvasive technique for assessment?

Objective

Vasculogenic mimicry (VM) is a novel mechanism of tumor blood supply distinct from endothelial vessel (EV). VM is associated with malignancy, invasion, metastasis, and poor prognosis. Hitherto a noninvasive method for the assessment of VM in vivo has been lacking.

Methods

Contrast-enhanced ultrasound (CEUS) was performed to evaluate the quantitative parameters of tumors in mice. CD31 immunohistochemistry-Periodic Acid-Schiff double staining was conducted to identify the VM or EV in tumor tissues. Correlations between perfusion parameters and VM density was analyzed by Pearson correlation test.

Results

By the 15th day after tumor inoculation, the EV and VM density was 31.15 ± 7.14 and 14.11 ± 2.99 per 200× field. The maximal intensity (IMAX) was 301.19 ± 191.56%, and the rise time (RT), time to peak (TTP) and mean transit time (mTT) were 17.38 ± 7.82 s, 20.27 ± 9.61 s and 58.09 ± 26.44 s, respectively. VM density positively correlated to RT (r = 0.3598, P = 0.0226), TTP (r = 0.3733, P = 0.0177) and mTT(r = 0.6483, P <  0.0001), whereas EV density positively correlated to IMAX (r = 0.4519, P = 0.0034). The vascular diameter of VM was substantially larger than that of EV (43.81 ± 5.88 μm vs 11.21 ± 4.13 μm).

Conclusion

Three quantitative parameters related to VM were obtained and the relationships between CEUS and VM were established. CEUS might thus provide a novel noninvasive method to assess VM in vivo.

The Roles of Common Variation and Somatic Mutation in Cancer Pharmacogenomics

Cancer pharmacogenomics is the science concerned with understanding genetic alterations and its effects on the pharmacokinetics and pharmacodynamics of anti-cancer drugs, with the aim to provide cancer patients with the precise medication that will achieve a good response and cause low/no incidence of adverse events. Advances in biotechnology and bioinformatics have enabled genomic research to evolve from the evaluation of alterations at the single-gene level to studies on the whole-genome scale using large-scale genotyping and next generation sequencing techniques. International collaborative efforts have resulted in the construction of databases to curate the identified genetic alterations that are clinically significant, and these are currently utilized in clinical sequencing and liquid biopsy screening/monitoring. Furthermore, countless clinical studies have accumulated sufficient evidence to match cancer patients to therapies by utilizing the information of clinical-relevant alterations. In this review we summarize the importance of germline alterations that act as predictive biomarkers for drug-induced toxicity and drug response as well as somatic mutations in cancer cells that function as drug targets. The integration of genomics into the medical field has transformed the era of cancer therapy from one-size-fits-all to cancer precision medicine.

Evolution of Cancer Pharmacological Treatments at the Turn of the Third Millennium

The medical history of cancer began millennia ago. Historical findings of patients with cancer date back to ancient Egyptian and Greek civilizations, where this disease was predominantly treated with radical surgery and cautery that were often ineffective, leading to the death of patients. Over the centuries, important discoveries allowed to identify the biological and pathological features of tumors, without however contributing to the development of effective therapeutic approaches until the end of the 1800s, when the discovery of X-rays and their use for the treatment of tumors provided the first modern therapeutic approach in medical oncology. However, a real breakthrough took place after the Second World War, with the discovery of cytotoxic antitumor drugs and the birth of chemotherapy for the treatment of various hematological and solid tumors. Starting from this epochal turning point, there has been an exponential growth of studies concerning the use of new drugs for cancer treatment. The second fundamental breakthrough in the field of oncology and pharmacology took place at the beginning of the '80s, thanks to molecular and cellular biology studies that allowed the development of specific drugs for some molecular targets involved in neoplastic processes, giving rise to targeted therapy. Both chemotherapy and target therapy have significantly improved the survival and quality of life of cancer patients inducing sometimes complete tumor remission. Subsequently, at the turn of the third millennium, thanks to genetic engineering studies, there was a further advancement of clinical oncology and pharmacology with the introduction of monoclonal antibodies and immune checkpoint inhibitors for the treatment of advanced or metastatic tumors, for which no effective treatment was available before. Today, cancer research is always aimed at the study and development of new therapeutic approaches for cancer treatment. Currently, several researchers are focused on the development of cell therapies, anti-tumor vaccines, and new biotechnological drugs that have already shown promising results in preclinical studies, therefore, in the near future, we will certainly assist to a new revolution in the field of medical oncology.

Analytical aspects of sunitinib and its geometric isomerism towards therapeutic drug monitoring in clinical routine

Sunitinib malate, an oral multi-targeted tyrosine kinase inhibitor approved for the treatment of metastatic renal cell carcinoma, gastrointestinal stromal tumor, and well-differentiated pancreatic neuroendocrine tumors, has been identified as a potential candidate for therapeutic drug monitoring approach. Nevertheless, the development of an analytical assay suitable for clinical application for the quantification of the plasma concentration of sunitinib and its active metabolite, N-desethyl sunitinib, is limited by its Z/E isomerization when exposed to light. Several LC-MS/MS methods already published require protection from light during all sample handling procedures to avoid the formation of E-isomer, which makes them not suitable for clinical practice. In order to obtain a simple and fast procedure to reconvert the E-isomer, formed during sample collection and treatment without light protection, and, thus, to have only Z-isomer peak to quantify, we studied the Z/E photodegradation with special attention to the condition allowing the reverse reaction in plasma matrix. After 30 min of light exposure, the E-isomer maximum percentage of both the analytes was reached (44% of E-sunitinib and 20% of E-N-desethyl sunitinib; these percentages were calculated with respect to the sum of E + Z). Moreover, the formation of the E-isomer increased up to 20% after lowering the pH of the solution. Since the reverse reaction takes place when the pre-exposed solution is placed in dark, we followed the E to Z-isomer kinetics into the autosampler. The conversion rate was very slow when the autosampler was set at 4 °C (after 4 h the mean percentages of E-isomer were 50% for sunitinib and 22% for N-desethyl sunitinib). The reconversion rate was considerably accelerated with the increasing of the temperature: incubating the analytical solution in a heated water bath for 5 min at 70 °C we obtained the quantitative (99%) reconversion of the E- to the Z-isomer. No effect of concentration was observed, while the presence of acids inhibited the reconversion. Based on these results, a simple and fast procedure was setup to quantitatively reconvert the E-isomer formed during sample collection and processing without light protection into its Z-form thus leading to a single peak to quantify. The application of this additional step allows to develop a LC-MS/MS method suitable to clinical practice, due to its practicality and speed.

Relationships between sunitinib plasma concentration and clinical outcomes in Japanese patients with metastatic renal cell carcinoma

BACKGROUND

The aim was to investigate the relationships between total sunitinib plasma concentrations (sunitinib plus its active metabolite; N-desethyl sunitinib) and clinical outcomes in Japanese patients with metastatic renal cell carcinoma (mRCC).

METHODS

Twenty patients with mRCC were enrolled following treatment with sunitinib. To assess safety, the total sunitinib concentration range up to discontinuation of treatment and dosage reduction associated with adverse events within 6 weeks from initiating administration were analyzed. The longest administered sunitinib dosage was defined as the maintenance dose, and the relationship between total sunitinib concentration at the maintenance dosage and sunitinib efficacy was investigated.

RESULTS

Total sunitinib concentration was significantly higher in patients who discontinued treatment or had dosage reduction due to adverse events within 6 weeks after initiation of sunitinib than in patients who continued treatment with the initial dosage. The time to treatment failure, progression-free survival, and overall survival were better in patients with total sunitinib concentrations < 50 ng/mL than in those with concentrations ≥ 50 ng/mL.

CONCLUSIONS

The present study demonstrated that the effective range of total sunitinib concentration in Japanese patients with mRCC was lower than 50-100 ng/mL which was previously reported. These results indicate that therapeutic drug monitoring could maintain the therapeutic effect of sunitinib while minimizing adverse events by personalizing sunitinib dosages for Japanese patients with mRCC.

Real-Time Apoptosis and Viability High-Throughput Screening of 3D Multicellular Tumor Spheroids Using the Celigo Image Cytometer

Three-dimensional tumor spheroid models have been increasingly used to investigate and characterize cancer drug compounds. Previously, the Celigo image cytometer has demonstrated its utility in a high-throughput screening manner for evaluating potential drug candidates in a 3D multicellular tumor spheroid (MCTS) primary screen. In addition, we have developed real-time kinetic caspase 3/7 apoptosis and propidium iodide viability 3D MCTS assays, both of which can be used in a secondary screen to better characterize the hit compounds. In this work, we monitored the kinetic apoptotic and cytotoxic effects of 14 compounds in 3D MCTS produced from the glioblastoma cell line U87MG in 384-well plates for 9 days. The kinetic results allowed the categorization of the effects from 14 drug compounds into early and late cytotoxic, apoptotic, cytostatic, and no effects. The real-time apoptosis and viability screening method can serve as an improved secondary screen to better understand the mechanism of action of these potential drug candidates identified from the primary screen, allowing one to identify a more qualified drug candidate and streamline the drug discovery process of research and development.

Prevalence of QT prolongation and associated LVEF changes in diabetic patients over a four-year retrospective time period

Aim: To evaluate the prevalence and longitudinal changes of prolonged QTc in DM patients admitted to our community hospital, and to determine, if any, its correlation with changes of left ventricular ejection fraction (LVEF). Methods: A retrospective chart review of patients with Type 1 (T1DM) and Type 2 (T2DM) with at least two admissions during a four-year period was performed to identify QTc interval, and LVEF, as measured on transthoracic echocardiogram. Changes in QTc and LVEF between patient hospital admissions were compared. Results: A prolonged QTc interval was found in 66.7% (n = 24) of type 1 and 51.3% (n = 154) type 2 diabetic patients. The QTc interval is progressively increased in both type 1 and type 2 diabetes during follow-up, although it did not reach statistical significance. A total of 62% patients (23 out 37 patients) had a reduction of LVEF during follow-up. Conclusion and Discussion: High prevalence of QTc prolongation was confirmed in hospitalized patients with in both T1DM and T2DM. Significant reduction of LVEF correlated with QTc prolongation over a mean of 17.3 months in T2DM patients, and may have implications for interventions.

Abbreviations CHF: Congestive heart failure LVEF: Left ventricular ejection fraction

Selective effects of oral antiangiogenic tyrosine kinase inhibitors on an animal model of hereditary hemorrhagic telangiectasia

Essentials Antiangiogenic drugs are indicated as therapies for hereditary hemorrhagic telangiectasia. We interrogated the response to four antiangiogenic drugs for anemia and intestinal bleeding. Sorafenib and a pazopanib analog significantly improved while erlotinib worsened anemia. Some oral antiangiogenic drugs were effective in reducing intestinal bleeding.

SUMMARY

Background Epistaxis and gastrointestinal (GI) tract hemorrhages are common symptoms of aged hereditary hemorrhagic telangiectasia (HHT) patients that result in anemia. Clinical as well as animal studies have suggested that vascular endothelial growth factor (VEGF) neutralizing antibodies lessen hemorrhage associated with adult-onset arteriovenous malformations (AVMs). Objectives The goal of this study is to evaluate potential therapeutic effects of oral delivery of four antiangiogenic tyrosine-kinase inhibitors (TKIs) in the development of adult-onset AVMs in a murine model of HHT. Methods An adult activin receptor-like kinase 1 (Alk1)-inducible knockout (iKO) model was utilized to evaluate the effect of oral administration of sorafenib, sunitinib, erlotinib and a pazopanib analog (GW771806) on hemoglobin level, GI hemorrhages and formation of wound-induced skin AVMs. Results and Conclusions Sorafenib and GW771806 significantly improved, yet erlotinib worsened, anemia and GI-bleeding in the Alk1-iKO model. However, none of these TKIs appeared to be effective for inhibiting the development of wound-induced skin AVMs. Taken together, these results suggest that oral delivery of antiangiogenic TKIs is selectively more effective for GI bleeding than mucocutaneous AVMs, and it may provide an experimental basis for selective therapeutic options depending on the symptoms of HHT.