Vorolanib, sunitinib, and axitinib: A comparative study of vascular endothelial growth factor receptor inhibitors and their anti-angiogenic effects.

PURPOSE: Pathological angiogenesis and vascular instability are observed in diabetic retinopathy (DR), diabetic macular edema (DME), and wet age-related macular degeneration (wAMD). Many receptor tyrosine kinases (RTKs) including vascular endothelial growth factor receptors (VEGFRs) contribute to angiogenesis, whereas the RTK TIE2 is important for vascular stability. Pan-VEGFR tyrosine kinase inhibitors (TKIs) such as vorolanib, sunitinib, and axitinib are of therapeutic interest over current antibody treatments that target only one or two ligands. This study compared the anti-angiogenic potential of these TKIs. METHODS: A kinase HotSpot™ assay was conducted to identify TKIs inhibiting RTKs associated with angiogenesis and vascular stability. Half-maximal inhibitory concentration (IC50) for VEGFRs and TIE2 was determined for each TKI. In vitro angiogenesis inhibition was investigated using a human umbilical vein endothelial cell sprouting assay, and in vivo angiogenesis was studied using the chorioallantoic membrane assay. Melanin binding was assessed using a melanin-binding assay. Computer modeling was conducted to understand the TIE2-axitinib complex as well as interactions between vorolanib and VEGFRs. RESULTS: Vorolanib, sunitinib, and axitinib inhibited RTKs of interest in angiogenesis and exhibited pan-VEGFR inhibition. HotSpot™ assay and TIE2 IC50 values showed that only axitinib potently inhibited TIE2 (up to 89%). All three TKIs effectively inhibited angiogenesis in vitro. In vivo, TKIs were more effective at inhibiting VEGF-induced angiogenesis than the anti-VEGF antibody bevacizumab. Of the three TKIs, only sunitinib bound melanin. TKIs differ in their classification and binding to VEGFRs, which is important because type II inhibitors have greater selectivity than type I TKIs. CONCLUSIONS: Vorolanib, sunitinib, and axitinib exhibited pan-VEGFR inhibition and inhibited RTKs associated with pathological angiogenesis. Of the three TKIs, only axitinib potently inhibited TIE2 which is an undesired trait as TIE2 is essential for vascular stability. The findings support the use of vorolanib for therapeutic inhibition of angiogenesis observed in DR, DME, and wAMD.

From Tumor to Bone: Growth Factor Receptors as Key Players in Cancer Metastasis.

This review article explores the intricate correlation between growth factors and bone metastases, which play a crucial role in the development of several types of malignancies, namely breast, prostate, lung, and renal cancers. The focal point of our discussion is on crucial receptors for growth factors, including Epidermal Growth Factor Receptor (EGFR), Transforming Growth Factor-ß (TGFß), Vascular Endothelial Growth Factor Receptor (VEGFR), and Fibroblast Growth Factor Receptor (FGFR). These receptors, which are essential for cellular activities including growth, differentiation, and survival, have important involvement in the spread of cancer and the interactions between tumors and the bone environment. We discuss the underlying mechanisms of bone metastases, with a specific emphasis on the interaction between growth factor receptors and the bone microenvironment. EGFR signaling specifically enhances the process of osteoclast development and the formation of osteolytic lesions, especially in breast and lung malignancies. TGFß receptors have a role in both osteolytic and osteoblastic metastases by releasing TGFß, which attracts cancer cells and promotes bone remodeling. This is a crucial element in the spread of prostate cancer to the bones. The functions of FGFR and VEGFR in the processes of bone formation and tumor angiogenesis, respectively, highlight the complex and diverse nature of these interactions. The review emphasizes the possibility of targeted therapeutics targeting these receptors to interrupt the cycle of tumor development and bone degradation. Therapeutic approaches include focusing on the VEGF/VEGFR, EGF/EGFR, FGF/FGFR, and TGFß/TGFßR pathways. These include a variety of compounds, such as small molecule inhibitors and monoclonal antibodies, which have shown potential to interfere with tumor-induced alterations in bone. The text discusses clinical trials and preclinical models, offering insights into the effectiveness and constraints of various treatments. Ultimately, this study provides a succinct but thorough summary of the present knowledge and treatment strategies focused on growth factor receptors in bone metastases. This highlights the significance of comprehending the signaling of growth factor receptors in the microenvironment where tumors spread to the bones, as well as the possibility of using targeted therapies to enhance the results for cancer patients with bone metastases. The advancement of treating bone metastases hinges on the development of treatments that specifically target the intricate relationships between malignancies and bone.

Progression of macular retinoschisis following intravitreal aflibercept injection for myopic macular neovascularization-a case report and review of literature.

BACKGROUND: Macular retinoschisis (MRS) and myopic macular neovascularization (mMNV) are both potentially blinding complications of high myopia. In this case report, we highlight the progression of MRS after intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment for mMNV, as well as an extensive review of the literature on this topic. CASE DESCRIPTION: A 49-year-old woman presented with two weeks of recent onset blurring and metamorphopsia in her right eye. She had high myopia in both eyes (right eye - 20/60 with - 16D, left eye - 20/20 with - 13D). Slit-lamp ophthalmoscopy found a normal anterior segment in both eyes. On fundus examination, features of pathological myopia with posterior staphyloma and peripapillary atrophy were observed in both eyes. An active mMNV, as well as intraretinal fluid, minimal perifoveal inner and outer MRS, and focal posterior vitreous traction along the inferotemporal retinal arcade, were detected on optical coherence tomography (OCT) of the right eye. The patient received an intravitreal injection of Aflibercept (2 mg/0.05 ml). RESULTS: OCT scans at two- and four-month follow-up visits revealed regressed mMNV with a taut epiretinal membrane, progressive worsening of outer MRS, and the development of multiple perifoveal retinal detachment inferior to the fovea. Pars plana vitrectomy surgery was performed for the progressive MRS with good anatomical (resolved MRS) and functional outcome (maintained visual acuity at 20/60) at the last one-month post-surgery visit. CONCLUSION: Intravitreal anti-VEGF injections for mMNV can cause vitreoretinal interface changes, exacerbating MRS and causing visual deterioration. Vitrectomy for MRS could be one of several treatment options.

Recent advances and future directions on small molecule VEGFR inhibitors in oncological conditions.

"A journey of mixed emotions" is a quote that best describes the progress chart of vascular endothelial growth factor receptor (VEGFR) inhibitors as cancer therapeutics in the last decade. Exhilarated with the Food and Drug Administration (FDA) approvals of numerous VEGFR inhibitors coupled with the annoyance of encountering the complications associated with their use, drug discovery enthusiasts are on their toes with an unswerving determination to enhance the rate of translation of VEGFR inhibitors from preclinical to clinical stage. The recently crafted armory of VEGFR inhibitors is a testament to their growing dominance over other antiangiogenic therapies for cancer treatment. This review perspicuously underscores the earnest attempts of the researchers to extract the antiproliferative potential of VEGFR inhibitors through the design of mechanistically diverse structural assemblages. Moreover, this review encompasses sections on structural/molecular properties and physiological functions of VEGFR, FDA-approved VEGFR inhibitors, and hurdles restricting the activity range/clinical applicability of VEGFR targeting antitumor agents. In addition, tactics to overcome the limitations of VEGFR inhibitors are discussed. A clear-cut viewpoint transmitted through this compilation can provide practical directions to push the cart of VEGFR inhibitors to advanced-stage clinical investigations in diverse malignancies.

An investigative meta-analysis on the effectiveness and safety of integrating VEGF/VEGFR inhibitors with PD-1/PD-L1 inhibitors in cases with R/M HNSCC.

OBJECTIVES: Exploration into the use of vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) inhibitors alongside programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors has been undertaken for treating recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC). We conducted a meta-analysis to provide a more precise assessment of the efficacy and safety of this integrated approach in managing R/M HNSCC. METHODS: A systematic exploration encompassing PubMed, Embase, the Cochrane Library, and Web of Science databases was undertaken to figure out relevant studies. It was attempted to analyze critical endpoints, such as overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and adverse events (AEs) utilizing a random-effects model. RESULTS: Eleven studies, encompassing 413 patients, were analyzed. The combined data revealed an ORR of 41 % (95 % CI: 34-49 %), a DCR of 67 % (95 % CI: 51-83 %), a median PFS of 5.87 months (95 % CI: 3.90-7.85), and a median OS of 9.63 months (95 % CI: 6.78-12.49). Furthermore, the rates for 1-year PFS and OS were 45 % (95 % CI: 27-64 %) and 65 % (95 % CI: 49-81 %), respectively. The occurrence of grade 3 or higher adverse events related to the drugs was 20 % (95 % CI: 10-30 %). Subgroup analysis within the tyrosine kinase inhibitor (TKI) group revealed an ORR of 47 % (95 % CI: 39 %-55 %) and a DCR of 67 % (95 % CI: 46 %-88 %). CONCLUSIONS: In summary, combining VEGF/VEGFR inhibitors with PD-1/PD-L1 inhibitors shows considerable effectiveness with manageable side effects in cases with R/M HNSCC. SYSTEMATIC REVIEW REGISTRATION: Registered with the International Prospective Register of Systematic Reviews, identifier CRD42023486345.

Comparison of ranibizumab, aflibercept, and dexamethasone implant monotherapy in treatment-naive eyes with diabetic macular edema: A 12-month real-life experience.

PURPOSE: To compare the functional and anatomical outcomes of ranibizumab, aflibercept, and dexamethasone implant monotherapy in treatment-naive eyes with diabetic macular edema (DME) in real-life conditions. METHODS: In this retrospective cohort study, data were obtained from the hospital database of treatment-naive patients diagnosed with DME with at least 12 months of follow-up. Best corrected visual acuity (BCVA) and central retinal thickness (CRT) at baseline, third month, sixth month, ninth month, and 12th month were recorded. In addition, a subgroup analysis was performed based on having good (below 0.4 log of minimum angle of resolution [logMAR]) or poor (0.4 logMAR and above) vision. RESULTS: A total of 219 eyes of 142 patients were included in the study. The change in the mean BCVA from baseline to 12th month was from 0.62 logMAR to 0.42 logMAR (P < 0.001) in the ranibizumab group, from 0.56 logMAR to 0.39 logMAR (P < 0.001) in the aflibercept group, and from 0.46 logMAR to 0.5 logMAR (P = 0.653) in the dexamethasone group. There was no significant difference between the treatment groups at any time point (P > 0.05). The mean amount of CRT change was statistically significant at 12 months in all groups (ranibizumab: -175.4 µm, aflibercept: -153.3 µm, dexamethasone: -71.4 µm) (P < 0.05). In eyes with initially good vision, the final BCVA at 12 months was significantly better in the ranibizumab group compared to the dexamethasone group (P = 0.008). The aflibercept group had better visual acuity than the dexamethasone group, but there was no statistically significant difference (P = 0.059). There was no significant difference in final BCVA in eyes with initially poor vision. No serious ocular/systemic complications were noted. CONCLUSION: At the 12th month, a significant decrease in CRT was achieved in all treatment groups, whereas only ranibizumab and aflibercept groups had a significant BCVA increase. In eyes with initially good vision, the final BCVA at 12 months was better in the ranibizumab group compared to the dexamethasone group, whereas it was similar in all groups having initially poor vision.

Unlocking Hope: Anti-VEGFR inhibitors and their potential in glioblastoma treatment.

PURPOSE: This systematic review summarizes evidence of VEGFR gene mutations and VEGF/VEGFR protein expression in glioblastoma multiforme (GBM) patients, alongside the efficacy and safety of anti-VEGFR tyrosine kinase inhibitors (TKIs) for GBM treatment. METHODS: A comprehensive literature review was conducted using PubMed up to August 2023. Boolean operators and MeSH term "glioma," along with specific VEGFR-related keywords, were utilized following thorough examination of existing literature. RESULTS: VEGFR correlates with glioma grade and GBM progression, presenting a viable therapeutic target. Regorafenib and axitinib show promise among studied TKIs. Other multi-targeted TKIs (MTKI) and combination therapies exhibit potential, albeit limited by blood-brain barrier penetration and toxicity. Combining treatments like radiotherapy and enhancing BBB penetration may benefit patients. Further research is warranted in patient quality of life and biomarker-guided selection. CONCLUSION: While certain therapies hold promise for GBM, future research should prioritize personalized medicine and innovative strategies for improved treatment outcomes.

Recent advances in tyrosine kinase inhibitors VEGFR 1-3 for the treatment of advanced metastatic melanoma.

INTRODUCTION: Increasing evidence from preclinical and clinical studies suggests the role of vascular endothelial growth factor (VEGF) signaling in melanoma progression, response to therapy, and overall survival. Moreover, the discovery of the potential involvement of the VEGF pathway in resistance to immunotherapy has led to new clinical trials with VEGFR inhibitors. AREAS COVERED: We have reviewed recent literature, mainly published within the last 5 years, on VEGFR-targeted treatments for advanced melanoma, including mucosal, acral, and uveal melanoma. The VEGFR inhibitors were used as a single therapy or combined with either immunotherapy or chemotherapy, and they were employed in treatment for KIT-mutated cutaneous melanoma and for patients with brain metastases. EXPERT OPINION: Trials involving monotherapy have been unsuccessful in demonstrating meaningful efficacy. Despite some activity, the combination of VEGFR-targeting tyrosine kinase inhibitors (TKIs) with immune checkpoint inhibitors (ICI) in patients with ICI-resistant melanoma, the combination did not significantly improve outcomes compared to anti-PD-1 monotherapy in the first-line settings. On the contrary, some patients with mucosal, acral or KIT-mutant melanoma may benefit from TKI-based therapies. Further studies focused on biomarker discovery and randomized trials are necessary to better understand the role of VEGFR1-3 as a therapeutic target in melanoma.

The effect of concomitant beta-blocker use on survival in patients with metastatic renal cell carcinoma treated with a vascular endothelial growth factor receptor inhibitors in the first line.

PURPOSE: Vascular endothelial growth factor (VEGF) inhibition is one of the cornerstones of treatment in the treatment of metastatic renal cell carcinoma (mRCC). Since RCC is a disease of advanced age and hypertension as a side effect of VEGF receptor inhibitors, beta-blocker use is common in these patients. We aimed to compare the treatment efficacy and survival results in case of concomitant use of these two drugs due to the inhibition of VEGF in beta-blockers. METHODS: A total of 121 patients with a diagnosis of mRCC who used sunitinib or pazopanib in first-line therapy were included in the study. These patients were divided into two groups as those using concomitant beta-blockers and those not using them. RESULT: The median overall survival (mOS) of the patient using sunitinib or pazopanib and concomitant beta-blocker was 47 (95% CI 29.0-65.0) months, and the mOS of those not using concomitant beta-blocker was 18 (95% CI 8.9-27.1) months (p < 0.001). The median progression-free survival (mPFS) of the patients using sunitinib or pazopanib and concomitant beta-blocker was 20.4 (95% CI 4.5-40.1) months, and the mPFS of those not using it was 11.4 (95% CI 5.9-16.9) months (p = 0.042). Concomitant beta-blocker use was found to be a good prognostic factor for OS in the multivariate analysis (p = 0.029). In the multivariate analysis, concomitant beta-blocker use had a trend towards statistical significance for PFS (p = 0.062). CONCLUSION: Concomitant use of betablockers with sunitinib or pazopanib is associated with longer overall survial and progression free survival.

Metabolism, toxicity and management of fruquintinib: a novel drug for metastatic colorectal cancer.

INTRODUCTION: Colorectal cancer (CRC) is the third most diagnosed cancer globally and despite therapeutic strides, the prognosis for patients with metastatic disease (mCRC) remains poor. Fruquintinib is an oral vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor (TKI) targeting VEGFR -1, -2, and -3, and has recently received approval by the U.S. Food and Drug Administration for treatment of mCRC refractory to standard chemotherapy, anti-VEGF therapy, and anti-epidermal growth factor receptor (EGFR) therapy. AREAS COVERED: This article provides an overview of the pre-clinical data, pharmacokinetics, clinical efficacy, and safety profile of fruquintinib, as well as the management of clinical toxicities associated with fruquintinib. EXPERT OPINION: Fruquintinib is a valuable additional treatment option for patients with refractory mCRC. The pivotal role of vigilant toxicity management cannot be understated. While fruquintinib offers a convenient and overall, well-tolerated treatment option, ongoing research is essential to determine its efficacy in different patient subsets, evaluate it in combination with chemotherapy and immunotherapy, and determine its role in earlier lines of therapy.

Prevalence and management of proteinuria associated with vascular endothelial growth factor receptor-targeted tyrosine kinase inhibitor treatment in advanced renal cell carcinoma, hepatocellular carcinoma, and thyroid cancer.

Vascular endothelial growth factor receptor-targeted tyrosine kinase inhibitors (VEGFR-TKIs) are often used for treatment of several types of cancer; however, they are associated with an increased risk of proteinuria, sometimes leading to treatment discontinuation. We searched PubMed and Scopus to identify clinical studies examining the incidence and risk factors for proteinuria caused by VEGFR-TKIs in patients with renal cell carcinoma, thyroid cancer, and hepatocellular carcinoma. The global incidence of proteinuria ranged from 6% to 34% for all grades of proteinuria, and from 1% to 10% for grade ≥3 proteinuria. The incidence of proteinuria did not differ significantly by cancer type, but in all three cancer types, there was a trend toward a higher incidence of proteinuria with lenvatinib than with other VEGFR-TKIs. In terms of risk factors, the incidence of proteinuria was significantly higher among Asians (including Japanese) compared with non-Asian populations. Other risk factors included diabetes mellitus, hypertension, and previous nephrectomy. When grade 3/4 proteinuria occurs, patients should be treated according to the criteria for dose reduction or withdrawal specified for each drug. For grade 2 proteinuria, treatment should be continued when the benefits outweigh the risks. Referral to a nephrologist should be considered for symptoms related to decreased renal function or when proteinuria has not improved after medication withdrawal. These management practices should be implemented universally, regardless of the cancer type.

Systemic Arterial and Venous Thrombotic Events Associated With Anti-Vascular Endothelial Growth Factor Injections: A Meta-Analysis.

PURPOSE: To compare the risk of systemic arteriovenous thrombotic events between intravitreal anti-vascular endothelial growth factor (anti-VEGF) and sham injections. DESIGN: Random-effects meta-analysis. METHODS: A systematic search was performed on OVID MEDLINE, Embase, and Cochrane Library from January 2005 to August 2023. Our inclusion criteria were randomized controlled trials (RCTs) reporting on systemic arteriovenous events for standard dose intravitreal anti-VEGF agents for any indication. RESULTS: A total of 20 RCTs reporting on 12,833 eyes were included. There was no significant difference in the risk of any thrombotic event between bevacizumab 1.25 mg and ranibizumab 0.5 mg (Risk ratio (RR) = 0.96, 95% CI = 0.52-1.75, P = .89). There was no significant difference between bevacizumab and ranibizumab when restricting to arterial thrombotic events (RR= 0.88, 95% CI = 0.60-1.30, P = .53) or venous thrombotic events (RR = 1.99, 95% CI =86 0.68-5.82], P = .21). The risk of arterial thrombotic events was similar between aflibercept and bevacizumab (RR = 1.11, 95% CI = 0.60-2.07, P = .74), between aflibercept and ranibizumab (RR= 0.77, 95% CI = 0.49-1.21, P = .26), between brolucizumab and aflibercept (RR= 0.67, 95% CI = 0.32-1.38, P = .27), and between aflibercept and faricimab (RR = 0.96, 95% CI = 0.43-2.17, P = .93). Compared to sham, neither dose of ranibizumab (0.5 mg or 0.3 mg) showed a higher risk of arterial thrombotic events. CONCLUSIONS: There was a similar risk of systemic arteriovenous thrombotic adverse events between anti-VEGF agents and between ranibizumab and sham injections.

Inhibition of VEGF receptors induces pituitary apoplexy: An experimental study in mice.

Anti-vascular endothelial growth factor (VEGF) therapy has been developed for the treatment of a variety of cancers. Although this therapy may be a promising alternative treatment for refractory pituitary adenomas and pituitary carcinomas, the effects of anti-VEGF agents on the pituitary gland are not yet well understood. Here, we found that mice administered with OSI-930, an inhibitor of receptor tyrosine kinases including VEGF receptor 1 and 2, frequently exhibited hemorrhage in the pituitary gland. This is the first report that anti-VEGF therapy can cause pituitary apoplexy. C57BL/6 mice were daily injected intraperitoneally with 100 mg/kg body weight of OSI-930 for one to six days. Pituitary glands were immunohistochemically examined. Four of six mice treated for three days and all of five mice treated for six days exhibited hemorrhage in the pituitary gland. In all cases, the hemorrhage occurred just around Rathke's cleft. In OSI-930-administered mice, the vascular coverage and branching were reduced in the anterior lobe, and capillary networks were also decreased in the intermediate lobe in a treatment-day dependent manner. Few blood vessels around Rathke's cleft of the intermediate lobe express VE-cadherin and are covered with platelet-derived growth factor receptor-ß (PDGFR-ß)-positive cells, which suggests that capillaries around Rathke's cleft of the intermediate lobe were VE-cadherin-negative and not covered with pericytes. The reduction of capillary plexus around Rathke's cleft was observed at the site where hemorrhage occurred, suggesting a causal relationship with the pathogenesis of pituitary hemorrhage. Our study demonstrates that anti-VEGF agents have a risk of pituitary apoplexy. Pituitary apoplexy should be kept in mind as an adverse effect of anti-VEGF therapy.

The effect of anti-PD-1/PD-L1 antibodies combined with VEGF receptor tyrosine kinase inhibitors versus bevacizumab in unresectable hepatocellular carcinoma.

Introduction: Immune checkpoint inhibition (ICI) plus bevacizumab (BEV) is the standard first-line treatment for unresectable hepatocellular carcinoma (uHCC). We aimed to assess the efficacy and safety of ICI plus bevacizumab and ICI plus receptor tyrosine kinase inhibitor (TKI) in this patient population. Methods: This retrospective single-institution study enrolled 94 patients with uHCC who received ICI plus TKI or bevacizumab as the first-line treatment. Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and disease control rate (DCR) were used to evaluate treatment efficacy. RECIST v1.1 criteria were used to calculate the objective clinical response. Common Terminology Criteria for Adverse Events were used to report and categorize adverse events. Results: By the last follow-up interview on May 15, 2022, there were 57 deaths, and 19 patients did not develop disease progression. Thirty patients received sintilimab/atezolizumab plus bevacizumab (ICI + BEV group), and 64 received ICI plus TKI (ICI + TKI group). The median OS was 430 days (95% CI, 266-NA) in the ICI+TKI group and 498 days (95% CI, 349-NA) in the ICI+BEV group (HR, 1.20; 95% CI, 0.69-2.07; P = 0.52). There was no significant difference between the two groups in the median PFS (182 vs. 221 days, P=0.67). In the ICI+TKI group, the ORR and DCR were 28.1% and 67.2%, respectively. In the ICI+BEV group, the ORR and DCR were 26.7% and 66.7%, respectively. The overall incidence of adverse events was similar between the two groups. Palmar-plantar erythrodysesthesia syndrome (23[36%]) occurred only in the ICI + TKI group. Patients who received ICI+BEV were more prone to upper gastrointestinal bleeding (2 [7%]), with one patient with grade 4 requiring emergency DSA treatment. Conclusion: This study found that ICI+TKI and ICI+BEV as first-line treatments were similar in OS, PFS, and tumor response in uHCC. Different populations are suitable for different regimens because of the different adverse events.

Targeting Vascular Endothelial Growth Factor Receptors as a Therapeutic Strategy for Osteoarthritis and Associated Pain.

Pain is the major reason that patients suffering from osteoarthritis (OA) seek medical care. We found that vascular endothelial growth factors (VEGFs) mediate signaling in OA pain pathways. To determine the specific contributions of VEGFs and their receptors (VEGFRs) to joint pathology and pain transmission during OA progression, we studied intra-articular (IA) injections of VEGF ligands into murine knee joints. Only VEGF ligands specific for the activation of VEGFR1, but not VEGFR2, induced allodynia within 30 min. Interventions in OA by inhibitors of VEGFRs were done in vivo using a preclinical murine OA model by IA injections of selective inhibitors of VEGFR1/VEGFR2 kinase (pazopanib) or VEGFR2 kinase (vandetanib). OA phenotypes were evaluated using pain-associated murine behavioral tests and histopathologic analyses. Alterations in VEGF/VEGFR signaling by drugs were determined in knee joints, dorsal root ganglia, and spinal cord by immunofluorescence microscopy. Pazopanib immediately relieved OA pain by interfering with pain transmission pathways. Pain reduction by vandetanib was mainly due to the inhibition of cartilage degeneration by suppressing VEGFR2 expression. In conclusion, IA administration of pazopanib, which simultaneously inhibits VEGFR1 and VEGFR2, can be developed as an ideal OA disease-modifying drug that rapidly reduces joint pain and simultaneously inhibits cartilage degeneration.

Final efficacy and safety results and biomarker analysis of a phase 2 study of cabozantinib in Japanese patients with advanced renal cell carcinoma.

BACKGROUND: Cabozantinib was established as the standard of care for the treatment of patients with renal cell carcinoma (RCC) whose disease had progressed after vascular endothelial growth factor receptor tyrosine kinase inhibitor (VEGFR-TKI) therapy in the global randomized trial METEOR. A phase 2 study was conducted to bridge the findings in METEOR to Japanese patients. Here, we report a biomarker analysis and update the efficacy and safety results of cabozantinib treatment. METHODS: Japanese patients with RCC who received at least one prior VEGFR-TKI were enrolled and received cabozantinib 60 mg orally once daily. The primary endpoint was objective response rate. Secondary endpoints included progression-free survival, overall survival, and safety. Exploratory analyses included the relationship between plasma protein hepatocyte growth factor (HGF) levels and treatment responses. RESULTS: In total, 35 patients were enrolled. The median treatment duration was 58.3 (range 5.1-131.4) weeks. The objective response rate was 25.7% (90% confidence interval [CI] 14.1-40.6). Kaplan-Meier estimate of median progression-free survival was 11.1 months (95% CI 7.4-18.4). The estimated progression-free survival proportion was 73.1% (95% CI 54.6-85.0) at 6 months. Median overall survival was not reached. Adverse events were consistent with those in METEOR and the safety profile was acceptable. Nonresponders to cabozantinib showed relatively higher HGF levels than responders at baseline. CONCLUSIONS: Updated analyses demonstrate the long-term efficacy and safety of cabozantinib in Japanese patients with advanced RCC after at least one VEGFR-TKI therapy. Responders tended to show lower baseline HGF levels ClinicalTrials.gov Identifier: NCT03339219.

A subset of VEGFR-TKIs activates AMPK in LKB1-mutant lung cancer.

The mutation of tumor suppressor gene liver kinase B1 (LKB1) has a prevalence of about 20% in non-small cell lung cancer (NSCLC). LKB1-mutant lung cancer is characterized by enhanced aggressiveness and immune escape and is associated with poor prognosis. Therefore, it is urgent to develop effective therapeutic methods for LKB1-mutant NSCLC. Recently, apatinib, a VEGFR-TKI, was found to significantly improve the outcome of LKB1-mutant NSCLC, but the mechanism is not completely clear. In this study, AMP-activated protein kinase (AMPK), the crucial downstream kinase of LKB1 was excavated as the potential target of apatinib. Biochemical experiments verified that apatinib is a direct AMPK activator. Moreover, clinically available VEGFR-TKIs were found to regulate AMPK differently: Apatinib and anlotinib can directly activate AMPK, while axitinib and sunitinib can directly inhibit AMPK. Activation of AMPK by apatinib leads to the phosphorylation of acetyl-CoA carboxylase (ACC) and inhibition of de novo fatty acid synthesis (FAsyn), which is upregulated in LKB1-null cancers. Moreover, the killing effect of apatinib was obviously enhanced under delipidated condition, and the combination of exogenous FA restriction with apatinib treatment can be a promising method for treating LKB1-mutant NSCLC. This study discovered AMPK as an important off-target of apatinib and elucidated different effects of this cluster of VEGFR-TKIs on AMPK. This finding can be the basis for the accurate and combined application of these drugs in clinic and highlights that the subset of VEGFR-TKIs including apatinib and anlotinib are potentially valuable in the treatment of LKB1-mutant NSCLC.

Case report: apatinib plus selexipag as a novel therapy for pulmonary tumor thrombotic microangiopathy accompanied by pulmonary hypertension associated with gastric carcinoma.

RATIONALE: PTTM is a rare but fatal disease, characterized by endothelial intimal proliferation and pulmonary hypertension due to micro-vascular remodeling. In view of the poor prognosis, new effective strategies are urgently required. PATIENT CONCERNS AND DIAGNOSIS: A 51-year-old woman was admitted to hospital for acute progressive dyspnea and dry cough. Clinical tests revealed hypercoagulable state and signs of severe pulmonary hypertension, without evidence of pulmonary embolism on contrast-enhanced CT. CT showed interlobular septal thickening and diffuse ground-glass opacity. Lung perfusion scan indicated multiple segment defect. Further right heart catherization proved a significant increase in pulmonary vascular resistance. INTERVENTIONS: A combination therapy of apatinib and selexipag was administered for treatment of PTTM. The conventional therapies of ventilation, anticoagulation and diuretic medicines were initiated after admission. OUTCOMES: Symptoms of PTTM were ameliorated with a reduction in pulmonary artery pressure. The resolution of interlobular septal thickening and ground-glass opacity on CT constituted the clinical benefits from treatment. LESSONS: Patient with PTTM will benefit from the combination strategy of apatinib, a VEGF-receptor antagonist, and selexipag, an oral prostacyclin receptor agonist.

VHL and DNA damage repair pathway alterations as potential clinical biomarkers for first-line TKIs in metastatic clear cell renal cell carcinomas.

PURPOSE: Vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs) are being used for the first-line treatment of metastatic clear cell renal cell carcinoma (mccRCC). Here, we set out to explore associations between genomic statuses, gene expression clusters and clinical outcomes of mccRCCs upon the application of VEGFR-TKIs. METHODS: A retrospective study of 56 patients with mccRCC who received first-line VEGFR-TKIs and who underwent genomic profiling and whole transcriptome sequencing was conducted. Survival analysis was carried out using log-rank tests and Cox regression analyses, and Kaplan-Meier curves were plotted. Clustering was performed using the K-means method. RESULTS: Among the 56 patients tested, 17 harbored DNA Damage and Repair (DDR) pathway alterations and 35 VHL mutations. The median progression-free survival (PFS) rates for the DDR and VHL alteration groups were 18 and 18 months, respectively, compared with 14 and 10 months for the nonmutant groups. DDR mutations, VHL mutations and co-mutations were identified as prognostic biomarkers of a longer PFS (p = 0.017, 0.04, 0.014). K-means clustering of expressed transcripts revealed three clusters of 40 patients: C_1, C_2 and C_3. The C_1 cluster exhibited the best PFS and objective response rate (ORR) to TKI therapy, with the highest proportion of DDR and VHL mutations. Further analysis of the tumor immune environment revealed that the C_1 cluster was enriched in activated CD8 T cells and effector CD4 T cells, whereas the C_2 cluster was enriched in eosinophils, mast cells and DC cells and, thus, in immunosuppressive cells. CONCLUSIONS: We found that patients with mccRCC harboring DDR and VHL alterations were more likely to benefit from first-line VEGF-TKI systemic therapy than patients with wild-type disease. In addition, we found that a three-cluster prognostic model based on gene expression can predict PFS and ORR, which was well-matched with activated TIL infiltration.