Sorafenib

Perioperative systemic treatments in renal cell carcinoma

In this review, we aim to provide a comprehensive assessment of the evolving landscape of the perioperative management in renal cell carcinoma (RCC), emphasizing its dynamic and intricate nature. We explore academic and clinical insights into the perioperative treatment paradigm of RCC. Up-to-date treatment options are discussed and the evolving role of neoadjuvant and adjuvant therapy in RCC is highlighted.

Novel 4-thiophenyl-pyrazole, pyridine, and pyrimidine derivatives as potential antitumor candidates targeting both EGFR and VEGFR-2; design, synthesis, biological evaluations, and in silico studies

In this article, we continued our previous effort to develop new selective anticancer candidates based on the basic pharmacophoric requirements of both EGFR and VEGFR-2 inhibitors. Therefore, twenty-two novel 4-thiophenyl-pyrazole, pyridine, and pyrimidine derivatives were designed and examined as dual EGFR/VEGFR-2 inhibitors. Besides, the previously reported antimicrobial activities of the aforementioned nuclei motivated us to screen their antibacterial and antifungal activities as well. First, the antitumor activities of the newly synthesized derivatives were evaluated against two cancer cell lines (HepG-2 and MCF-7). Notably, compounds 2a, 6a, 7a, 10b, 15a, and 18a exhibited superior anticancer activities against both HepG-2 and MCF-7 cancer cell lines. These candidates were selected to further evaluate their anti-EGFR and anti-VEGFR-2 potentialities which were found to be very promising compared to erlotinib and sorafenib, respectively. Both 10b and 2a derivatives achieved better dual EGFR/VEGFR-2 inhibition with IC₅₀ values of 0.161 and 0.141 μM and 0.209 and 0.195 μM, respectively. Moreover, the most active 10b was selected to evaluate the exact phase of cell cycle arrest and to investigate the exact mechanism of cancer cell death whether it be due to apoptosis or necrosis. On the other hand, all the synthesized compounds were tested against Gram-positive bacteria such as S. aureus and B. subtilis as well as Gram-negative bacteria such as E. coli and P. aeuroginosa. Also, the antifungal activity was investigated against C. albicans and A. flavus strains. The findings of the antimicrobial tests revealed that most of the investigated compounds exhibited strong to moderate antibacterial and antifungal effects. Furthermore, to understand the pattern by which the investigated compounds bound to the active site, all the newly synthesized candidates were subjected to two different docking processes into the EGFR and VEGFR-2 binding sites. Besides, we tried to correlate compound 10b and the reference drugs (erlotinib and sorafenib) through DFT calculations. Finally, following the biological data of the new pyrazole, pyridine, and pyrimidine derivatives as anticancer and antimicrobial candidates, we concluded a very interesting SAR for further optimization.

Sorafenib inhibits ovarian cancer cell proliferation and mobility and induces radiosensitivity by targeting the tumor cell epithelial–mesenchymal transition

Sorafenib, a pan-protein kinase inhibitor, inhibits the activity of various kinases (like vascular endothelial growth factor, platelet-derived growth factor, and rapidly accelerated fibrosarcoma) and clinically has been used to treat different human cancers. This study investigated its antitumor activity in ovarian cancer and the underlying molecular events. To achieve that, ovarian cancer SKOV-3 cells were treated with or without sorafenib (10 µM), transforming growth factor (TGF)-β1 (10 ng/mL), sorafenib (10 µM) + TGF-β1 (10 ng/mL), and TGF-β1 (10 ng/mL) + Ly2157299 (5 µM), followed by 8-Gy radiation. The cells were then subjected to cell viability, wound healing, Transwell, caspase-3 activity, and western blot assays. TGF-β1 treatment enhanced ovarian cancer cell epithelial–mesenchymal transition (EMT), whereas sorafenib and a selective TGF-β1 inhibitor Ly2157299 reversed tumor cell EMT, invasion, and expression of EMT markers (E-cadherin and vimentin). Sorafenib and Ly2157299 treatment also significantly reduced the tumor cell viability. Furthermore, both sorafenib and Ly2157299 significantly enhanced ovarian cancer cell radiosensitivity, as assessed by a caspase-3 activity assay. In conclusion, sorafenib inhibited ovarian cancer cell proliferation and mobility and induced tumor cell radiosensitivity. Molecularly, sorafenib could inhibit the TGF-β1-mediated EMT. Future studies will assess sorafenib anti-ovarian cancer activity plus TGF-β1 inhibitors in ovarian cancer in vivo.

Pharmacokinetic Exposures Associated With Oral Administration of Sorafenib in Dogs With Spontaneous Tumors

Sorafenib is a multi-kinase small molecule inhibitor that targets serine/threonine and tyrosine kinases including the RAF kinase family, VEGFR-2, and PDGFR. The aim of this study was to evaluate the systemic pharmacokinetics of a previously defined tolerable oral dose of sorafenib in tumor-bearing dogs. Six client-owned dogs with a cytologic or histologic diagnosis of cancer were enrolled in this open-label, tolerability study. Dogs were administered sorafenib at an intended dose of 3 mg/kg and serum samples were obtained for analysis of sorafenib serum concentrations at 0, 1, 2, 6, 12, 24, 48, 72, 96, and 168 h post-drug administration. Median time to peak serum sorafenib concentration occurred at 4 h (range 2–12 h) resulting in an average serum concentration of 54.9 ± 33.5 ng/mL (118.2 ± 72.1 nM). Mean sorafenib levels declined by over 70% relative to peak serum concentrations by 24 h in all dogs, suggesting the value of at least twice daily administration. Doses of 3 mg/kg were well-tolerated and no patients in the study experienced adverse events that were attributable to sorafenib. Future trials in dogs with cancer are recommended at this dosing schedule to assess the effect of sorafenib administration on anti-tumor efficacy signals and relevant pharmacodynamic target modulation in vivo.

Design, synthesis, and SAR studies of novel 4-methoxyphenyl pyrazole and pyrimidine derivatives as potential dual tyrosine kinase inhibitors targeting both EGFR and VEGFR-2

Guided by the pharmacophoric features of both EGFR and VEGFR-2 antagonists, two novel series of 4-methoxyphenyl pyrazole and pyrimidine derivatives [(4a-c) and (5a-c, 6, 7a-c, 8, 9, 10, 11a,c, 12, 13a-c, 14a-c, and 15a,b)], respectively, were designed and synthesized as dual EGFR/VEGFR-2 inhibitors. Interestingly, compound 12 showed very strong antiproliferative effects towards all the five studied cell lines (HepG-2, MCF-7, MDA-231, HCT-116, and Caco-2) with IC₅₀ values of 3.74, 7.81, 4.85, 2.96, and 9.27 µM, respectively. Also, it achieved the highest inhibitory activities against both EGFR and VEGFR-2 as well (IC₅₀ = 0.071 and 0.098 µM) compared to the two reference drugs, erlotinib (IC₅₀ = 0.063 µM) and sorafenib (IC₅₀ = 0.041 µM), respectively. Moreover, four compounds (4a, 7a, 7c, and 12) were selected for further evaluation through cell cycle analysis and Annexin V-based flow cytometry assay in the HepG-2 cell line. In addition, deep computational studies including molecular docking, physicochemical properties, profiling pharmacokinetics, ADMET studies, and toxicity predictions were performed for the designed compounds to evaluate the prospective drug candidates. Finally, analyzing the structure-activity relationship (SAR) of the new derivatives gives us a lot of interesting promising results which could help medicinal chemists to design more potent drug candidates soon as well.

Phase 1 study of sorafenib and irinotecan in pediatric patients with relapsed or refractory solid tumors

BACKGROUND

Sorafenib,an orally bioavailable, multitarget tyrosine kinase inhibitor, and irinotecan, a topoisomerase I inhibitor, have demonstrated activity in pediatric and adult malignancies. We evaluated the toxicity, pharmacokinetic (PK), and pharmacogenomic (PGX) profile of sorafenib with irinotecan in children with relapsed or refractory solid tumors and assessed the feasibility of incorporating patient-reported outcome (PRO) measures as an adjunct to traditional endpoints.

METHODS

Sorafenib, continuous oral twice daily dosing, was administered with irinotecan, orally, once daily days 1-5, repeated every 21 days (NCT01518413). Based on tolerability, escalation of sorafenib followed by escalation of irinotecan was planned. Three patients were initially enrolled at each dose level. Sorafenib and irinotecan PK analyses were performed during cycle 1. PRO measurements were collected during cycles 1 and 2.

RESULTS

Fifteen patients were evaluable. Two of three patients at dose level 2 experienced dose-limiting toxicity (DLT), grade 3 diarrhea, and grade 3 hyponatremia. Therefore, dose level 1 was expanded to 12 patients and two patients had DLT, grade 4 thrombocytopenia, grade 3 elevated lipase. Nine of 15 (60%) patients had a best response of stable disease with four patients receiving ≥6 cycles.

CONCLUSIONS

The recommended dose for pediatric patients was sorafenib 150 mg/m² /dose twice daily with irinotecan 70 mg/m² /dose daily × 5 days every 21 days. This oral outpatient regimen was well tolerated and resulted in prolonged disease stabilization. There were no significant alterations in the PK profile of either agent when administered in combination. Patients were willing and able to report their subjective experiences with this regimen.

Modeling Neoplastic Growth in Renal Cell Carcinoma and Polycystic Kidney Disease

Renal cell carcinoma (RCC) and autosomal dominant polycystic kidney disease (ADPKD) share several characteristics, including neoplastic cell growth, kidney cysts, and limited therapeutics. As well, both exhibit impaired vasculature and compensatory VEGF activation of angiogenesis. The PI3K/AKT/mTOR and Ras/Raf/ERK pathways play important roles in regulating cystic and tumor cell proliferation and growth. Both RCC and ADPKD result in hypoxia, where HIF-α signaling is activated in response to oxygen deprivation. Primary cilia and altered cell metabolism may play a role in disease progression. Non-coding RNAs may regulate RCC carcinogenesis and ADPKD through their varied effects. Drosophila exhibits remarkable conservation of the pathways involved in RCC and ADPKD. Here, we review the progress towards understanding disease mechanisms, partially overlapping cellular and molecular dysfunctions in RCC and ADPKD and reflect on the potential for the agile Drosophila genetic model to accelerate discovery science, address unresolved mechanistic aspects of these diseases, and perform rapid pharmacological screens.

Epithelial Transfer of the Tyrosine Kinase Inhibitors Erlotinib, Gefitinib, Afatinib, Crizotinib, Sorafenib, Sunitinib, and Dasatinib: Implications for Clinical Resistance

Simple Summary

Tyrosine kinase inhibitors (TKIs) specifically inhibit phosphorylation of signaling pathways of cancer cells, thereby inhibiting their growth. They are characterized by a poor solubility and high protein binding, leading to a large variability in gut uptake after oral administration and variation in the clinical efficacy. We used the CaCo2 gut epithelial model to characterize the gut absorption of 7 TKIs and observed a large variation in apical/basolateral (mimicking gut/blood) transfer, with 4 TKIs showing a negative and 3 a neutral transfer. A highly negative transfer may lead to pharmacokinetic resistance. Intracellular uptake of TKIs was high for sunitinib and crizotinib, intermediate for gefitinib, dasatinib and sorafenib, low for afatinib and not detectable for erlotinib. These properties may explain a high red blood cell to plasma ratio for most TKIs investigated. Although TKIs are poorly absorbed the latter property may compensate for this.

Abstract

Background: tyrosine kinase inhibitors (TKIs) inhibit phosphorylation of signaling proteins. TKIs often show large variations in the clinic due to poor pharmacology, possibly leading to resistance. We compared gut absorption of inhibitors of epidermal growth factor receptor (erlotinib, gefitinib, and afatinib), ALK-cMET (crizotinib), PDGFR/BCR-Abl (dasatinib), and multikinase inhibitors (sunitinib and sorafenib). In clinical samples, we measured the disposition of each compound within various blood compartments. Methods: we used an optimized CaCo2 gut epithelial model to characterize 20 µM TKI absorption. The apical/basolateral transfer is considered to represent the gut/blood transfer. Drugs were measured using LC-MS/MS. Results: sorafenib and sunitinib showed the highest apical/basolateral transfer (Papp 14.1 and 7.7 × 10⁻⁶ cm/s, respectively), followed by dasatinib (3.4), afatinib (1.5), gefitinib (0.38), erlotinib (0.13), and crizotinib (n.d.). However, the net absorptions for dasatinib, afatinib, crizotinib, and erlotinib were highly negative (efflux ratios >5) or neutral/negative, sorafenib (0.86), gefitinib (1.0), and sunitinib (1.6). A high negative absorption may result in resistance because of a poor exposure of tissues to the drug. Accumulation of the TKIs at the end of the transfer period (A->B) was not detectable for erlotinib, very low for afatinib 0.45 pmol/μg protein), followed by gefitinib (0.79), dasatinib (1.1), sorafenib (1.65), and crizotinib (2.11), being highest for sunitinib (11.9). A similar pattern was found for accumulation of these drugs in other colon cell lines, WiDr and HT29. In clinical samples, drugs accumulated consistently in red blood cells; blood to plasma ratios were all >3 (sorafenib) or over 30 for erlotinib. Conclusions: TKIs are consistently poorly absorbed, but accumulation in red blood cells seems to compensate for this.

Nanotechnology for angiogenesis: opportunities and challenges

Angiogenesis plays a critical role within the human body, from the early stages of life (i.e., embryonic development) to life-threatening diseases (e.g., cancer, heart attack, stroke, wound healing). Many pharmaceutical companies have expended huge efforts on both stimulation and inhibition of angiogenesis. During the last decade, the nanotechnology revolution has made a great impact in medicine, and regulatory approvals are starting to be achieved for nanomedicines to treat a wide range of diseases. Angiogenesis therapies involve the inhibition of angiogenesis in oncology and ophthalmology, and stimulation of angiogenesis in wound healing and tissue engineering. This review aims to summarize nanotechnology-based strategies that have been explored in the broad area of angiogenesis. Lipid-based, carbon-based and polymeric nanoparticles, and a wide range of inorganic and metallic nanoparticles are covered in detail. Theranostic and imaging approaches can be facilitated by nanoparticles. Many preparations have been reported to have a bimodal effect where they stimulate angiogenesis at low dose and inhibit it at higher doses.

Antitumor Effects of Trimethylellagic Acid Isolated From Sanguisorba officinalis L. on Colorectal Cancer via Angiogenesis Inhibition and Apoptosis Induction

Previous studies have demonstrated that tannin could inhibit the proliferation and angiogenesis of cancer cells. However, the mechanism(s) associated with its antitumor effect remains unclear. Here, we investigated the effects of 3,3',4'-trimethylellagic acid (TMEA), a tannin compound isolated from Sanguisorba officinalis L., on the proliferation, angiogenesis, and apoptosis in cancer cells, as well as the underlying mechanism(s) related to its antitumor activity. TMEA was isolated from Sanguisorba officinalis L. by silica gel column chromatography. Molecular docking was carried out to assess active pocket binding between TMEA and vascular endothelial growth factor receptor 2 (VEGFR2). The antiangiogenic effect of TMEA on the migration and tube formation was detected in HUVECs by wound healing and tube formation assays, respectively. The antitumor effects of TMEA on the cell proliferation were determined in HepG2, A549, and SW620 cells by MTS assay in vitro and on the tumor growth of SW620 xenografts bearing in nude mice in vivo. The mRNA expression of Bcl-2, Bax, caspase-3, VEGF, PI3K, and mTOR were measured by qRT-PCR and protein expression of Bcl-2, Bax, caspase-3, VEGF, PI3K, and mTOR by Western blotting, and the protein expression of Bcl-2, Bax, caspase-3 and CD31 were detected by immunohistochemical analysis in vivo, respectively. The results showed that TMEA combined with VEGFR2 in the functional pockets of Asn223A, Gly922A, and Leu840A and inhibited the proliferation, migration, tube formation, and expression of VEGF and its downstream signaling mediators in HUVECs. TMEA also significantly inhibited the proliferation of HepG2, A549, and SW620 cancer cells in vitro, and suppressed the growth of SW620 tumors in vivo. Moreover, TMEA upregulated the expression of proapoptotic factors Bax and caspase-3 and downregulated the expression of antiapoptotic factors CD31 and Bcl-2 in cancer cells and/or tumor tissues. The data indicate that TMEA executes its anticancer activity by inducing apoptosis and inhibiting angiogenesis in cancer cells in vitro and tumor growth in vivo. The underlying anticancer mechanism is associated with the apoptotic and VEGF/PI3K/AKT/mTOR pathways.

Changes in population-level survival for advanced solid malignancies with new treatment options in the second decade of the 21st century

BACKGROUND

Several new treatments that improve survival in clinical trials have been developed for various solid malignancies in advanced stages. The effect of these options on survival in the general population is currently unknown.

METHODS

Cancers for which 2 or more new treatment options have been approved by the US Food and Drug Administration during the years 2009 through 2011 for the treatment of advanced disease were identified, including adenocarcinoma of the lung, melanoma, breast cancer, prostate cancer, and renal cell carcinoma. Kaplan-Meier analysis was used to compare overall survival for these conditions in the Surveillance, Epidemiology, and End Results database for the periods 2007 to 2008, 2009 to 2010, and 2011 to 2012. Hazard ratios derived from adjusted, shared frailty models for cancer-specific survival were calculated as well for the years of diagnosis (2007-2008, 2009-2010, and 2011-2012).

RESULTS

Two-year survival increased for patients with advanced-stage lung adenocarcinoma (+3.0 percentage points), melanoma (+3.4 percentage points), and breast cancer (+2.7 percentage points). When only patients aged 15 to 64 years were included, 2-year survival for those with melanoma increased by +6.7 percentage points. No change in survival was observed for renal cell carcinoma. Decreases in the hazard ratio for cancer-specific mortality were observed during the period 2011 to 2012 compared with 2007 to 2008 for lung adenocarcinoma, melanoma, and breast cancer.

CONCLUSIONS

Small increases in 2-year survival were observed between the periods 2007 to 2008 and 2011 to 2012 for lung adenocarcinoma, melanoma, and prostate cancer. Cancer-specific mortality decreased for each of these cancers among patients who were diagnosed between the periods 2007 to 2008 and 2011 to 2013. These findings suggest that newer treatment options are beginning to increase survival for stage IV cancers at the population level.

Efficacy and safety of sorafenib for advanced renal cell carcinoma: real-world data of patients with renal impairment

Background

We retrospectively analysed the efficacy and safety of sorafenib in patients with advanced renal cell carcinoma with renal impairment.

Methods

Patients were divided into two groups by an estimated glomerular filtration rate (eGFR) cut-off of 45 mL/min/1.73 m². Background factors considered to affect prognosis were well balanced by propensity score matching between the groups. Demographics, dose modification, adverse events, tumour response, progression-free survival, and renal function (eGFR) were evaluated.

Results

Among 935 and 2008 patients with an eGFR of <45 and ≥45, respectively, 613 pairs were matched. The mean starting dose was significantly lower in patients with an eGFR of <45; however, the mean daily dose, median treatment duration, progression-free survival, and tumour response were similar between the groups. In terms of safety, no significant differences were found in serious adverse events, although cytopaenia (16.6% vs 10.6%) and renal dysfunction (4.4% vs 0.7%) were higher in patients with an eGFR of <45 than ≥45 in all adverse events. There were also no differences in dose modification, including dose reduction, dose interruption, and treatment discontinuation.

Conclusion

Throughout the 12-month observation period, sorafenib in patients with an eGFR of <45 and ≥45 showed similar safety and efficacy, and treatment was continued without affecting renal function.

Characterizing nanoscale changes in the activity of VEGFR-2 on glioma microvascular endothelial cell membranes using atomic force microscopy

The aim of the current study was to demonstrate the distribution of VEGFR-2 on glioma microvascular endothelial cells on a nanoscale and investigate changes in VEGFR-2 activity following treatment with the VEGFR-2 inhibitor and agonist sorafenib and bradykinin, respectively. Three groups were evaluated in this study: Control glioma microvascular endothelial cells, sorafenib-treated glioma microvascular endothelial cells and bradykinin-treated glioma microvascular endothelial cells. Changes in the activity of VEGFR-2 on the glioma microvascular endothelial cell membranes following treatment with sorafenib and bradykinin were characterized by atomic force microscopy (AFM). Colloidal gold-labeled immune complexes and AFM were used to visualize the distribution of VEGFR-2 on the cell membranes. In the control group, VEGFR-2, which was observed as numerous globular structures, was evenly distributed on the cell surface membranes. The majority of the receptors were active. In the sorafenib group, only a few globular structures were observed on the cell membranes, with a density significantly lower than that in the control group (P<0.01). Furthermore, compared with the control group, fewer of the receptors were active. In the bradykinin group, numerous globular structures were densely distributed on the cell membranes, with a density significantly higher than that in the control group (P<0.01). The distribution and activity of VEGFR-2 on glioma microvascular endothelial cell membranes treated with sorafenib and bradykinin suggested that the activity of VEGFR-2 could be regulated by its inhibitor or agonist.

Sorafenib for the treatment of multiple myeloma

INTRODUCTION

Sorafenib is an orally available compound that acts predominantly by targeting the Ras/Raf/MEK/ERK pathway and by inhibiting the vascular endothelial growth factor (VEGF). Since the Ras/Raf/MEK/ERK pathway is implicated in the proliferation of multiple myeloma (MM) cells and VEGF in bone marrow neovascularization, sorafenib is a drug offering the potential for targeting two important pathogenetic mechanisms involved in MM. Thus, sorafenib is being proposed for use in MM.

AREAS COVERED

In this review, the authors discuss the rationale for the use of sorafenib in MM. They then summarize the clinical development of sorafenib in MM, from initial Phase I to Phase II studies. A systematic literature review of the trials was performed using PubMed.

EXPERT OPINION

Preliminary data from phase I/II trials showed that sorafenib had a good safety profile but minimal anti-myeloma activity as a single agent in relapsed/refractory patients. Results of phase II trials, evaluating sorafenib combined with new drugs, such as bortezomib and lenalidomide are eagerly awaited.

Efficacy of BIBF 1120 or BIBF 1120 plus chemotherapy on nasopharyngeal carcinoma in vitro and in vivo

Purpose

BIBF 1120 is a potent triple angiokinase inhibitor now being evaluated in many types of tumors. We examine the antitumor effects of BIBF 1120 on nasopharyngeal carcinoma (NPC) in vitro and in vivo.

Materials and methods

The effect of BIBF 1120 on NPC cell proliferation was evaluated using the Cell Counting Kit 8 assay. The activities of BIBF 1120 as a single agent and in combination with cisplatin (DDP) in NPC tumor xenografts were evaluated by measuring microvessel density and expression of vascular endothelial growth factor signaling.

Results

BIBF 1120 exhibited limited inhibition of the growth of three NPC cell lines. Concurrent administration of BIBF 1120 and DDP provided greater antitumor effects compared to that observed with the use of either inhibitor as a single agent in the NPC xenograft model. Microvessel density and expression of vascular endothelial growth factor signaling were significantly reduced.

Conclusion

BIBF 1120, either as a single agent or in combination with DDP, demonstrates significant antitumor and antiangiogenic effects in the NPC xenograft model. Our results indicate that BIBF 1120 administered in conjunction with chemotherapy might provide an effective treatment method for NPC.

Safe handling of oral antineoplastic medications: Focus on targeted therapeutics in the home setting

Introduction With the growing number of oral targeted therapies being approved for use in cancer therapy, the potential for long-term administration of these drugs to cancer patients is expanding. The use of these drugs in the home setting has the potential to expose family members and caregivers to them either through direct contact with the drugs or indirectly by exposure to the parent compounds and/or their active metabolites in contaminated patients' waste. Methods A systematic literature review was performed and the known adverse health effect of 32 oral targeted therapeutics is summarized. In particular, the carcinogenicity, genotoxicity, and embryo-fetal toxicity, along with the route of excretion were evaluated. Results Carcinogenicity testing has not been performed on most of the oral targeted therapeutics and the genotoxicity data are mixed. However, the majority of these drugs exhibit adverse reproductive effects, some of which are severe. Currently, available data does not permit the possibility of a health hazard from inappropriate handling of drugs and contaminated patients waste to be ignored, especially in a long-term home setting. Further research is needed to understand these issues. Conclusions With the expanding use of targeted therapies in the home setting, family members and caregivers, especially those of reproductive risk age, are, potentially at risk. Overall basic education and related precautions should be taken to protect family members and caregivers from indirect or direct exposure from these drugs. Further investigations and discussion on this subject are warranted.

Sorafenib inhibits proliferation and invasion of human hepatocellular carcinoma cells via up-regulation of p53 and suppressing FoxM1

AIM

Forkhead box M1 (FoxM1) is a transcription factor that plays important roles in the pathogenesis and progression of human cancers, including hepatocellular carcinoma (HCC). The aim of this study was to examine the involvement of FoxM1 in the anti-cancer action of sorafenib, a multikinase inhibitor, in human HCC cells.

METHODS

HCC cell lines HepG2 and HuH-7 were tested. Cell viability was examined using MTT assay and cell invasion was determined with Transwell migration assay. The relevant mRNA expression was determined with RT-PCR, and the proteins were detected using Western blotting and immunofluorescence assays. RNA interference was used to modify the expression of p53 and FoxM1. HuH-7 cell line xenograft mice were used for in vivo study, which were treated with sorafenib (40 mg/kg, po) daily for 3 weeks.

RESULTS

Sorafenib (2-20 μmol/L) inhibited the proliferation of the cells in dose- and time-dependent manners with an IC50 value of nearly 6 μmol/L at 48 h. Sorafenib (6 μmol/L) markedly suppressed the cell invasion. Furthermore, sorafenib (2-6 μmol/L) dose-dependently decreased the expression of FoxM1, MMP-2, and Ki-67, and up-regulated that of p53 in the cells. Silencing p53 abolished the decrease of FoxM1 and increase of p53 in sorafenib-treated cells. Silencing FoxM1 significantly reduced the expression of MMP-2 and Ki-67, and enhanced the anti-proliferation action of sorafenib in the cells, whereas overexpression of FoxM1 increased the expression of MMP-2 and Ki-67, and abrogated the anti-proliferation action of sorafenib. In the xenograft mice, sorafenib administration decreased the tumor growth by 40%, and markedly increased the expression of p53, and decreased the expression of FoxM1, MMP-2, and Ki-67 in tumor tissues.

CONCLUSION

Sorafenib inhibits HCC proliferation and invasion by inhibiting MMP-2 and Ki-67 expression due to up-regulation of P53 and suppressing FoxM1.

Converting biology into clinical benefit: lessons learned from BRAF inhibitors

The identification and pharmacological targeting of activating BRAF mutations in melanoma has led to significant improvements in patient outcomes. This perspective paper illustrates the lessons learned from the study of BRAF mutations and the development of BRAF inhibitors. The relevance of these lessons to the development of future targeted therapies is highlighted.

The role of death receptor 3 in the biological behavior of hepatocellular carcinoma cells

Death receptor 3 (DR3) belongs to the tumor necrosis factor (TNF) receptor superfamily, primarily found in lymphoid tissues. Reports have determined that DR3 may also be distributed in numerous types of tumors. Therefore, it is thought that DR3 may have an important role in the process of tumorigenesis. The aim of the present study was to observe the effect of silencing DR3 expression on hepatocarcinoma cell growth, apoptosis and invasion in order to elucidate the role of DR3 in tumor development. The hepatocarcinoma cell lines (HepG2, Huh7, SMMC7721 and Bel-7402) and normal human liver cells (HL-7702) were transfected with three stealth RNA interference (RNAi) sequences that target the DR3 gene. Reverse transcription quantitative polymerase chain reaction was used to detect the expression levels of DR3 in hepatocarcinoma cell lines and normal liver HL-7702 cells. MTT assay and flow cytometry (FCM) were used to determine the rates of cell proliferation and apoptosis, respectively. Following silencing of the DR3 gene, western blot analysis was used to determine the protein expression of P53, Fas, Caspase8, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and Caspase3. DR3 messenger RNA (mRNA) expression in hepatocarcinoma cell lines was significantly increased compared with that in the normal liver cell line. Three targeted DR3 gene small interfering RNAs significantly inhibited DR3 gene expression in Bel-7402 cells at the nucleic acid level. AF02670.1_stealth_883 and cocktail demonstrated the most efficient inhibition of DR3 gene expression at 48 and 72 h following transfection, with mRNA inhibition rates of 89.46 and 92.75%, and 90.53 and 94.25% (P<0.01), respectively. Cell viability was significantly reduced by AF02670.1_stealth_883 and RNAi cocktail at 24, 48 and 72 h following transfection. The inhibition rates of cell proliferation were 50.76 and 61.76% (P<0.05) at 72 h following transfection. FCM revealed that AF02670.1_stealth_883 and RNAi cocktail also induced apoptosis in Bel-7402 cells at 72 h following transfection. Reduction of NF-κB and P53 levels was observed (P<0.05) in Bel-7402 cells following DR3 silencing, whereas levels of Fas, Caspase3 and Caspase8 were markedly elevated (P<0.05). DR3 expression levels in hepatocellular carcinoma cells were significantly higher than those in normal cells. DR3 silencing effectively inhibited proliferation and invasion of hepatocellular carcinoma cells in vitro. However, silencing of the DR3 gene affect levels of apoptosis antigen-3 ligand in cells, therefore indicating that it may be involved with other pathways that regulate apoptosis in HCCs. In conclusion, the results of the present study indicated that DR3 may be a promising therapeutic target molecule for further study of hepatocellular carcinoma gene therapy.

Antitumor activity of sorafenib and imatinib in a patient with thymic carcinoma harboring c-KIT exon 13 missense mutation K642E

We report the case of a man with an advanced nonkeratinizing squamous cell thymic carcinoma harboring c-KIT exon 13 missense mutation K642E. This aberration is rare and has never been described previously in patients with thymic cancers. It has been found in a small number of cases of gastrointestinal stromal tumor and also in several cases of acral and mucosal melanomas. Some of the patients with gastrointestinal stromal tumor or melanoma harboring this rare mutation have had a tumor response when treated with imatinib. In contrast, in our case, the mutation was associated with primary resistance to full doses of imatinib but, at the same time, it was not a cause of resistance to sorafenib.

Comparison of systems for assessment of post-therapeutic response to sorafenib for hepatocellular carcinoma

BACKGROUND

To test the hypothesis that use of the response evaluation criteria in cancer of the liver (RECICL), an improved evaluation system designed to address the limitations of the response evaluation criteria in solid tumors 1.1 (RECIST1.1) and modified RECIST (mRECIST), provides for more accurate evaluation of response of patients with hepatocellular carcinoma (HCC) to treatment with sorafenib, a molecularly targeted agent, as assessed by overall survival (OS).

METHODS

The therapeutic response of 156 patients with advanced HCC who had been treated with sorafenib therapy for more than 1 month was evaluated using the RECIST1.1, mRECIST, and RECICL. After categorization as showing progressive disease (PD), stable disease (SD), or objective response, the association between OS and categorization was examined using the Kaplan-Meier method to develop survival curves. The 141 cases categorized as PD or SD by the RECIST1.1, but objective response by the mRECIST and RECICL, were further analyzed for determination of the association between OS and categorization.

RESULTS

Only categorization using the RECICL was found to be significantly correlated with OS (p = 0.0033). Among the patients categorized as SD or PD by the RECIST1.1, reclassification by the RECICL but not the mRECIST was found to be significantly associated with OS and allowed for precise prediction of prognosis (p = 0.0066).

CONCLUSIONS

Only the use of the RECICL allowed for identification of a subgroup of HCC patients treated with sorafenib with improved prognosis. The RECICL should, therefore, be considered a superior system for assessment of therapeutic response.

Role of chemokines and their receptors in chronic lymphocytic leukemia: function in microenvironment and targeted therapy

Chemokines produced in distinct tissue microenvironments sustain migration of mature lymphocytes in lymphoglandula. Chemokine receptors expressed on chronic lymphocytic leukemia (CLL) cells regulate the migration of the leukemia cells within the bone marrow (BM), lymphoid organs in collaboration with chemokines. Chemokines form a pro-survival circuitry by regulating leukocyte trafficking, maintaining extended lymphocyte survival. Therefore, chemokines in tumor cell-microenvironment interactions represent a target for treatment of CLL. AMD3100 disrupts the CLL/microenvironment interactions and influences CXCL12/CXCR4 survival signaling. Fostamatinib, ibrutinib, and GS-1101 as B-cell receptor (BCR)-related kinase inhibitors inhibit BCR- and chemokine-receptor-signal-regulated kinase and have a good clinical response in CLL. Lenalidomide, sorafenib, and dasatinib are other additional drugs associated with chemokine in microenvironment. Inhibiting signaling through chemokine and microenvironment associated signaling are emerging as innovative therapeutic targets in CLL. In this article, we reviewed the role of chemokines in CLL microenvironment and novel therapeutics targeting CLL microenvironment.

From a multipotent stilbene to soluble epoxide hydrolase inhibitors with antiproliferative properties

Inspired by nature: Natural product isopropylstilbene was identified as an inhibitor of soluble epoxide hydrolase exhibiting antiproliferative properties. Following the natural product inspired design approach, a library of (E)-styryl-1H-benzo[d]imidazoles was synthesized and evaluated with recombinant enzyme and on several cancer cell lines.

Potent in vitro and in vivo activity of sorafenib in multiple myeloma: induction of cell death, CD138-downregulation and inhibition of migration through actin depolymerization

Despite considerable advances, multiple myeloma (MM) remains incurable and the development of novel therapies targeting the interplay between plasma cells (PCs) and their bone marrow (BM) microenvironment remains essential. We investigated the effect of various agents in vitro on the proliferation, phenotype, morphology, actin polymerization and migration of MM cells and, in vivo, the tumour growth of L363-bearing non-obese diabetic severe combined immunodeficient mice with a deficient interleukin-2 receptor gamma chain (NSG). In vitro, we observed a dose-dependent cytotoxicity with bortezomib and sorafenib. Using RPMI8226 cells co-expressing histone 2B-mCherry and cytochrome c-GFP, bortezomib- and sorafenib-induced apoptosis was confirmed, and both agents combined showed synergism. Sorafenib induced CD138-downregulation and abolished CXCL12-induced actin polymerization. L363 cells expressed CCR4 and CCR5 and migrated to their common ligand CCL5. Chemotaxis to BM stroma cells was notable and significantly reduced by sorafenib. Downregulation of phospho-ERK appeared relevant for the inhibition of actin polymerization and chemotaxis. Sorafenib alone, and combined with bortezomib, showed substantial antitumour activity in L363-bearing NSG. Correspondingly, sorafenib induced clinical responses in MM-/AL-amyloidosis patients. We conclude that, in addition to the cytotoxic and anti-angiogenic effects of sorafenib, blocking of MM cell migration and homing represent promising mechanisms to interrupt the interplay between PCs and their supportive microenvironment.

Sorafenib has potent antitumor activity against multiple myeloma in vitro, ex vivo, and in vivo in the 5T33MM mouse model

Multiple myeloma (MM) is a B-cell malignancy characterized by the expansion of clonal plasma blasts/plasma cells within the bone marrow that relies on multiple signaling cascades, including tyrosine kinase activated pathways, to proliferate and evade cell death. Despite emerging new treatment strategies, multiple myeloma remains at present incurable. Thus, novel approaches targeting several signaling cascades by using the multi-tyrosine kinase inhibitor (TKI), sorafenib, seem a promising treatment approach for multiple myeloma. Here, we show that sorafenib induces cell death in multiple myeloma cell lines and in CD138(+)-enriched primary multiple myeloma patient samples in a caspase-dependent and -independent manner. Furthermore, sorafenib has a strong antitumoral and -angiogenic activity in the 5T33MM mouse model leading to increased overall survival. Multiple myeloma cells undergo autophagy in response to sorafenib, and inhibition of this cytoprotective pathway potentiated the efficacy of this TKI. Mcl-1, a survival factor in multiple myeloma, is downregulated at the protein level by sorafenib allowing for the execution of cell death, as ectopic overexpression of this protein protects multiple myeloma cells. Concomitant targeting of Mcl-1 by sorafenib and of Bcl-2/Bcl-xL by the antagonist ABT737 improves the efficacy of sorafenib in multiple myeloma cell lines and CD138(+)-enriched primary cells in the presence of bone marrow stromal cells. Altogether, our data support the use of sorafenib as a novel therapeutic modality against human multiple myeloma, and its efficacy may be potentiated in combination with ABT737.

Novel targeted agents for the treatment of advanced breast cancer

The discovery of the molecular processes involved in cancer development has led to the design of an array of targeted agents. These agents, directed to specific proteins in the machinery of cancer cells, interfere with vital cascades involved in cell invasion, metastasis, apoptosis, cell-cycle control and angiogenesis. In breast cancer, the main pathways studied and targeted by drugs are the HER2 pathway, EGFR, VEGF, PI3K/Akt/mammalian target of rapamycin (PI3K-M-Tor), IGF/IGFR, poly(ADP ribose) polymerase 1, HDAC and many others. In this review, we present the most promising studies of these new targeted therapies and novel combination of targeted therapies with cytotoxic agents for the treatment of breast cancer patients.

Radiofrequency ablation or percutaneous ethanol injection for the treatment of liver tumors

The liver is a common location of both primary and secondary malignancies. For unresectable liver cancer, many local ablative therapies have been developed. These include e.g., percutaneous ethanol injection (PEI), percutaneous acetic acid injection, radiofrequency ablation (RFA), cryoablation, microwave ablation, laser-induced thermotherapy, and high-intensity focused ultrasound. RFA has recently gained interest and is the most widely applied thermoablative technique. RFA allows more effective tumor control in fewer treatment sessions compared with PEI, but with a higher rate of complications. However, there are certain circumstances where PEI therapy represents a better strategy to control liver tumors than RFA, especially in situations where RFA is difficult, for example when large vessels surround the tumor. In the context of hepatocellular carcinoma (HCC), both RFA and PEI are feasible and of benefit in non-operable patients. RFA seems superior to PEI in HCC > 2 cm, and the combination of interventions may be of benefit in selected patients. Liver resection is superior to RFA for patients with HCC meeting the Milan criteria, but RFA can be employed in tumors ≤ 3 cm and where there is an increased expected operative mortality. In addition, some lines of evidence indicate that RFA and PEI can be employed as a bridge to liver transplantation. The use of RFA in colorectal liver metastases is currently limited to unresectable disease and for patients unfit for surgery. The aim of this article is to summarize the current status of RFA in the management of liver tumors and compare it to the cheap and readily available technique of PEI.

Anti-angiogenic therapy in glioma

There has been great interest in developing anti-angiogenic therapies for the treatment of patients with high-grade gliomas. In fact, some anti-angiogenic agents are now routinely used for the treatment of patients with glioblastoma. However, the use of these agents is largely based on trials which indicate an initial radiographic response, while it remains unclear whether any anti-angiogenic therapies tested to date have improved the overall survival of patients with malignant glial tumours. This manuscript reviews the landscape of anti-angiogenic therapy in glioma, with a focus on GBM, and demonstrates that further innovation is needed to determine the true utility of anti-angiogenic therapy.

Molecular predictors of response to antiangiogenesis therapies

Angiogenesis is a crucial component of tumor growth and metastasis. Targeting the vascular endothelial growth factor pathway represents therapeutic potentials for treating cancer. To date, 3 Food and Drug Administration-approved agents targeting angiogenesis have been developed, bevacizumab, sunitinib, and sorafenib. However, no validated biomarkers are available to identify those patients who are likely to benefit from antiangiogenesis therapy. Molecular biomarker research in antiangiogenesis inhibition is an actively growing field. Although current data are extremely promising, it is still uncertain which biomarker(s) can reliably predict their efficacy. With increasing numbers of inhibitors being developed, the need for biomarkers is more critical than ever. This review will focus on translational research that strives to identify molecular biomarkers (tissue, circulating and genomic) for approved antiangiogenesis therapies that can indicate benefit, resistance, and toxicity.

Present and future evolution of advanced breast cancer therapy

Although the introduction of novel therapies and drug combinations has improved the prognosis of metastatic breast cancer, the disease remains incurable. Increased knowledge of the biology and the molecular alterations in breast cancer has facilitated the design of targeted therapies. These agents include receptor and nonreceptor tyrosine kinase inhibitors (epidermal growth factor receptor family), intracellular signaling pathways (phosphatidylinositol-3-kinase, AKT, mammalian target of rapamycin) angiogenesis inhibitors and agents that interfere with DNA repair (poly(ADP-ribose) polymerase inhibitors). In the present review, we present the most promising studies of these new targeted therapies and novel combinations of targeted therapies with cytotoxic agents.

New anti-angiogenic strategies in pediatric solid malignancies: agents and biomarkers of a near future

IMPORTANCE OF THE FIELD

Antiangiogenic strategies are affording considerable interest and have become a major milestone in therapeutics of various adult cancers. However, progress has been slow to expand such therapies to patients with pediatric solid malignancies.

AREAS COVERED IN THIS REVIEW

This review discusses the principal pathways for angiogenesis in pediatric solid malignancies and summarizes recent preclinical and clinical data on antiangiogenesis strategies in these tumors.

WHAT THE READER WILL GAIN

The reader will gain state-of-the-art knowledge in the current advancements of antiangiogenic therapies in pediatric clinical trials in regard to supporting preclinical data, and in the status of potential biomarkers investigated for monitoring angiogenesis inhibitors. Mechanisms of resistance to antiangiogenic therapy will also be discussed. Finally, we describe our experience in the monitoring of circulating endothelial cells and progenitors and their potential role as biomarkers of metastatic disease and resistance to antiangiogenic therapies.

TAKE HOME MESSAGE

Evaluation and development of antiangiogenesis protocols are starting and represent a crucial step in the management of pediatric solid malignancies today. Emphasis should be placed on the development of proper surrogate markers to monitor antiangiogenic activity and on the possible long-term effects of these therapies in a pediatric population.

Sorafenib activates CD95 and promotes autophagy and cell death via Src family kinases in gastrointestinal tumor cells

Sorafenib and vorinostat interact in a synergistic fashion to kill carcinoma cells by activating CD95; the present studies have determined how sorafenib and vorinostat individually contribute to CD95 activation. Sorafenib (3-6 micromol/L) promoted a dose-dependent increase in Src Y416, ERBB1 Y845 and CD95 Y232/Y291 phosphorylation, and Src Y527 dephosphorylation. Low levels of sorafenib-induced (3 micromol/L) CD95 tyrosine phosphorylation did not promote surface localization whereas sorafenib (6 micromol/L), or sorafenib (3 micromol/L) and vorinostat (500 nmol/L) treatment promoted higher levels of CD95 phosphorylation which correlated with DISC formation, receptor surface localization, and autophagy. CD95 (Y232F, Y291F) was not tyrosine phosphorylated and was unable to localize plasma membrane or induce autophagy. Knockdown/knockout of Src family kinases abolished sorafenib-induced CD95 tyrosine phosphorylation, DISC formation, and the induction of cell death and autophagy. Knockdown of platelet-ived growth factor receptor-beta enhanced Src Y416 and CD95 tyrosine phosphorylation, which correlated with elevated CD95 plasma membrane levels and autophagy, and with a reduced ability of sorafenib to promote CD95 membrane localization. Vorinostat increased reactive oxygen species levels, and in a delayed NF kappa B-dependent fashion, those of FAS ligand and CD95. Neutralization of FAS-L did not alter the initial rapid drug-induced activation of CD95; however, neutralization of FAS-L reduced sorafenib + vorinostat toxicity by approximately 50%. Thus, sorafenib contributes to CD95 activation by promoting receptor tyrosine phosphorylation, whereas vorinostat contributes to CD95 activation via the initial facilitation of reactive oxygen species generation and subsequently of FAS-L expression.

Vorinostat and sorafenib increase CD95 activation in gastrointestinal tumor cells through a Ca(2+)-de novo ceramide-PP2A-reactive oxygen species-dependent signaling pathway

The targeted therapeutics sorafenib and vorinostat interact in a synergistic fashion to kill carcinoma cells by activating CD95, and this drug combination is entering phase I evaluation. In this study, we determined how CD95 is activated by treatment with this drug combination. Low doses of sorafenib and vorinostat, but not the individual drugs, rapidly increased reactive oxygen species (ROS), Ca(2+), and ceramide levels in gastrointestinal tumor cells. The production of ROS was reduced in Rho zero cells. Quenching ROS blocked drug-induced CD95 surface localization and apoptosis. ROS generation, CD95 activation, and cell killing was also blocked by quenching of induced Ca(2+) levels or by inhibition of PP2A. Inhibition of acidic sphingomyelinase or de novo ceramide generation blocked the induction of ROS; however, combined inhibition of both acidic sphingomyelinase and de novo ceramide generation was required to block the induction of Ca(2+). Quenching of ROS did not affect drug-induced ceramide/dihydro-ceramide levels, whereas quenching of Ca(2+) reduced the ceramide increase. Sorafenib and vorinostat treatment radiosensitized liver and pancreatic cancer cells, an effect that was suppressed by quenching ROS or knockdown of LASS6. Further, sorafenib and vorinostat treatment suppressed the growth of pancreatic tumors in vivo. Our findings show that induction of cytosolic Ca(2+) by sorafenib and vorinostat is a primary event that elevates dihydroceramide levels, each essential steps in ROS generation that promotes CD95 activation.

A pharmacodynamic study of sorafenib in patients with relapsed and refractory acute leukemias

We report the results of a Phase I dose escalation trial of the multikinase inhibitor sorafenib in relapsed/refractory acute leukemias using an intermittent dosing regimen. Fifteen patients with advanced leukemia (Acute myeloid leukemia(AML), 2=Acute lymphoblastic leukemia(ALL), 1 Biphenotypic) and a median age of 63 (range 37–85) years were enrolled and treated on a dose escalation trial. Toxicities ≥grade 3 were present in 55% of cycles and the maximum tolerated dose (MTD) was determined to be 400mg BID × 21days in a 28 day cycle. Plasma inhibitory assays of kinase targets ERK and FLT3-ITD demonstrated excellent target inhibition, with FLT3-ITD silencing occurring below the MTD. The N-oxide metabolite of sorafenib appeared to be a more potent inhibitor of FLT3-ITD than the parent compound. Despite marked ex vivo FLT-3 ITD inhibition, no patients met criteria for complete or partial response in this monotherapy study. Eleven of fifteen patients experienced stable disease as best response. Although sorafenib demonstrated only modest clinical activity as a single agent in this heavily treated population, robust inhibition of FLT3 and ERK suggest there may be a potential important role in combination therapies.

Sorafenib combined vitamin K induces apoptosis in human pancreatic cancer cell lines through RAF/MEK/ERK and c-Jun NH2-terminal kinase pathways

Apoptosis has been shown to be induced by many agents, including the clinically useful Sorafenib and K vitamins (VKs). Since few agents have activity against pancreas cancer cell growth, we evaluated the role of naturally occurring K vitamins and Sorafenib both independently and together on the growth in culture of pancreas adenocarcinoma cell lines, including PL-5, PANC-1, and MIA PaCa-2. We found that when a K vitamin was combined with Sorafenib, the dose of Sorafenib required for growth inhibition was substantially reduced. Furthermore, growth could be inhibited at doses of each VK plus Sorafenib in combination that were ineffective when used alone. This effect was seen using vitamins K1, K2, and K5. The combination of VK1 plus Sorafenib-induced apoptosis, as determined by both FACS and TUNEL staining. Phospho-ERK and Bcl-2 levels were decreased, but not levels of other bcl-2 family members. Cleavage of caspases 3 and 8, PARP and Bid were all induced by this combination. Vitamin K1 plus Sorafenib combination also resulted in elevated levels of activated c-Jun N-terminal kinase (JNK) and its substrates c-Jun and FasL. JNK inhibition partly antagonized the induction of apoptosis. Thus, combination VK1 plus Sorafenib strongly induced growth inhibition and apoptosis in pancreas cancer cells, involving both inhibition of the RAF/MEK/ERK pathway as well as activation of the JNK, c-Jun and FasL apoptotic pathway. Since both agents are available for human use, the combination is attractive for evaluation against pancreas cancer growth in vivo.

The role of antiangiogenesis therapy: bevacizumab and beyond

The importance of angiogenesis in tumour growth and development is well known. Overexpression of vascular endothelial growth factor (VEGF), the key mediator of angiogenesis, is associated with poor prognosis in cancer. As a result, several therapeutic agents that inhibit the actions of VEGF or its receptors are currently in development for use in advanced solid tumours, such breast, colorectal, lung and renal cancer. Clinical data from trials of anti-VEGF agents in this group of tumours are discussed, with a particular focus on the efficacy and safety of bevacizumab, the anti-VEGF agent at the most advanced stage of development in those tumour types. Future potential uses of bevacizumab in cancer therapy will be discussed.

Pathways mediating VEGF-independent tumor angiogenesis

FDA approval of several inhibitors of the VEGF pathway has enabled significant advances in the therapy of cancer and neovascular age-related macular degeneration. However, similar to other therapies, inherent/acquired resistance to anti-angiogenic drugs may occur in patients, leading to disease progression. So far the lack of predictive biomarkers has precluded identification of patients most likely to respond to such treatments. Recent suggest that both tumor and non-tumor (stromal) cell types are involved in the reduced responsiveness to the treatments. The present review examines the role of tumor- as well as stromal cell-derived pathways involved in tumor growth and in refractoriness to anti-VEGF therapies.