Toripalimab plus axitinib versus sunitinib as first-line treatment for advanced renal cell carcinoma: RENOTORCH, a randomized, open-label, phase III study

BACKGROUND

Immune checkpoint inhibitors in combination with tyrosine kinase inhibitors are standard treatments for advanced clear cell renal cell carcinoma (RCC). This phase III RENOTORCH study compared the efficacy and safety of toripalimab plus axitinib versus sunitinib for the first-line treatment of patients with intermediate-/poor-risk advanced RCC.

PATIENTS AND METHODS

Patients with intermediate-/poor-risk unresectable or metastatic RCC were randomized in a ratio of 1 : 1 to receive toripalimab (240 mg intravenously once every 3 weeks) plus axitinib (5 mg orally twice daily) or sunitinib [50 mg orally once daily for 4 weeks (6-week cycle) or 2 weeks (3-week cycle)]. The primary endpoint was progression-free survival (PFS) assessed by an independent review committee (IRC). The secondary endpoints were investigator-assessed PFS, overall response rate (ORR), overall survival (OS), and safety.

RESULTS

A total of 421 patients were randomized to receive toripalimab plus axitinib (n = 210) or sunitinib (n = 211). With a median follow-up of 14.6 months, toripalimab plus axitinib significantly reduced the risk of disease progression or death by 35% compared with sunitinib as assessed by an IRC [hazard ratio (HR) 0.65, 95% confidence interval (CI) 0.49-0.86; P = 0.0028]. The median PFS was 18.0 months in the toripalimab-axitinib group, whereas it was 9.8 months in the sunitinib group. The IRC-assessed ORR was significantly higher in the toripalimab-axitinib group compared with the sunitinib group (56.7% versus 30.8%; P < 0.0001). An OS trend favoring toripalimab plus axitinib was also observed (HR 0.61, 95% CI 0.40-0.92). Treatment-related grade ≥3 adverse events occurred in 61.5% of patients in the toripalimab-axitinib group and 58.6% of patients in the sunitinib group.

CONCLUSION

In patients with previously untreated intermediate-/poor-risk advanced RCC, toripalimab plus axitinib provided significantly longer PFS and higher ORR than sunitinib and had a manageable safety profile TRIAL REGISTRATION: ClinicalTrials.gov NCT04394975.

Mutant IDH1 Promotes Glioma Formation In Vivo

Isocitrate dehydrogenase 1 (IDH1) is the most commonly mutated gene in grade II–III glioma and secondary glioblastoma (GBM). A causal role for IDH1^R132H in gliomagenesis has been proposed, but functional validation in vivo has not been demonstrated. In this study, we assessed the role of IDH1^R132H in glioma development in the context of clinically relevant cooperating genetic alterations in vitro and in vivo. Immortal astrocytes expressing IDH1^R132H exhibited elevated (R)-2-hydroxyglutarate levels, reduced NADPH, increased proliferation, and anchorage-independent growth. Although not sufficient on its own, IDH1^R132H cooperated with PDGFA and loss of Cdkn2a, Atrx, and Pten to promote glioma development in vivo. These tumors resembled pro-neural human mutant IDH1 GBM genetically, histologically, and functionally. Our findings support the hypothesis that IDH1^R132H promotes glioma development. This model enhances our understanding of the biology of IDH1^R132H-driven gliomas and facilitates testing of therapeutic strategies designed to combat this deadly disease.

Species-specific maturation profiles of human, chimpanzee and bonobo neural cells

Comparative analyses of neuronal phenotypes in closely related species can shed light on neuronal changes occurring during evolution. The study of post-mortem brains of nonhuman primates (NHPs) has been limited and often does not recapitulate important species-specific developmental hallmarks. We utilize induced pluripotent stem cell (iPSC) technology to investigate the development of cortical pyramidal neurons following migration and maturation of cells grafted in the developing mouse cortex. Our results show differential migration patterns in human neural progenitor cells compared to those of chimpanzees and bonobos both in vitro and in vivo, suggesting heterochronic changes in human neurons. The strategy proposed here lays the groundwork for further comparative analyses between humans and NHPs and opens new avenues for understanding the differences in the neural underpinnings of cognition and neurological disease susceptibility between species.

HBEGF promotes gliomagenesis in the context of Ink4a/Arf and Pten loss

Heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF) is a ligand for the epidermal growth factor receptor (EGFR), one of the most commonly amplified receptor tyrosine kinases (RTK) in glioblastoma. While HBEGF has been found to be expressed in a subset of malignant gliomas, its sufficiency for glioma initiation has not been evaluated. In this study, we demonstrate that HBEGF can initiate glioblastoma (GBM) in mice in the context of Ink4a/Arf and Pten loss, and that these tumors are similar to the classical GBM subtype observed in patients. Isogenic astrocytes from these mice showed activation not only of Egfr but also the RTK Axl in response to HBEGF stimulation. Deletion of either Egfr or Axl decreased the tumorigenic properties of HBEGF transformed cells; however only EGFR was able to rescue the phenotype in cells lacking both RTKs indicating that Egfr is required for activation of Axl in this context. Silencing of HBEGF in vivo resulted in tumor regression and significantly increased survival suggesting that HBEGF may be a clinically relevant target.

Abstract 274: Assessing combinations of chemotherapy in alveolar soft part sarcoma cell lines

Background: Alveolar Soft Part Sarcoma (ASPS) is a rare soft tissue sarcoma subtype occurring mainly in children and young adults. Malignant tumors develop in the connective tissues, typically in the lower extremities of the legs and thighs, but can also be found in the head and neck regions. ASPS is slow growing, highly angiogenic, and may have unique metabolic properties. ASPS is characterized by an unbalanced translocation between the ASPSCR1 gene (whose product tethers GLUT4 transporters) and the TFE3 gene (encoding a transcription factor). The resulting ASPSCR1-TFE3 fusion gene is responsible for an aberrant transcription factor that is thought to be involved in the pathogenesis of the disease. Methods to assess a number of different agents in combination are needed for practical use in clinical trials.

Methods: Here, we seek to examine the therapeutic activity of single agent and combinations of epigenetic, anti-angiogenic and a diverse mix of other mechanisms of action agents using high-throughput screening platforms and well-established cell line models for ASPS (ASPS-1 and ASPS-KY). We designed stringent screening conditions that assess the compounds at clinically-relevant concentrations and time of exposures that mimic the in vivo pharmacokinetics in an effort to maximize the translational potential of these results to the clinical setting. 54 agents were screened across the 2 cell lines with attention to existing clinical data and angiogenesis inhibitors. The cell titer glo assay was used to determine cell viability at three clinically achievable concentrations for all agents. The most promising 8 agents were then studied in all two-drug combinations to evaluate for synergy.

Results: The results of our screening showed that several agents significantly reduced cell viability at clinically relevant concentrations and exposure times with belinostat (an HDAC inhibitor) and dinaciclib (a CDK 1, 2, 5 and 9 inhibitor) in particular having good activity. Several combinations with doxorubicin showed good efficacy and synergy. Belinostat and doxorubicin affected both ASPS-KY and ASPS-1 cell lines similarly, with an average fraction affected (FA) of 0.87. The combination index (CI) indicated strong synergy in the ASPS-KY (CI = 0.09) and some synergy in ASPS-1 (CI = 0.74). Similarly, dinaciclib and doxorubicin produced a FA of 0.85 with good synergy (CI of 0.51-0.66). In addition, the combination of belinostat and tivantinib showed additive effects in both cell lines (CI of 0.88-1.2) with a FA of ∼0.8. These findings suggest potentially promising opportunities for developing combinational approach to treating childhood soft tissue sarcomas.

Citation Format: Justine Clark, Elliot Kahen, Diana X. Yu, Christopher L. Cubitt, Daniel M. Sullivan, Damon R. Reed. Assessing combinations of chemotherapy in alveolar soft part sarcoma cell lines. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 274.

Differential responses to lithium in hyperexcitable neurons from patients with bipolar disorder

Bipolar disorder is a complex neuropsychiatric disorder that is characterized by intermittent episodes of mania and depression; without treatment, 15% of patients commit suicide. Hence, it has been ranked by the World Health Organization as a top disorder of morbidity and lost productivity. Previous neuropathological studies have revealed a series of alterations in the brains of patients with bipolar disorder or animal models, such as reduced glial cell number in the prefrontal cortex of patients, upregulated activities of the protein kinase A and C pathways and changes in neurotransmission. However, the roles and causation of these changes in bipolar disorder have been too complex to exactly determine the pathology of the disease. Furthermore, although some patients show remarkable improvement with lithium treatment for yet unknown reasons, others are refractory to lithium treatment. Therefore, developing an accurate and powerful biological model for bipolar disorder has been a challenge. The introduction of induced pluripotent stem-cell (iPSC) technology has provided a new approach. Here we have developed an iPSC model for human bipolar disorder and investigated the cellular phenotypes of hippocampal dentate gyrus-like neurons derived from iPSCs of patients with bipolar disorder. Guided by RNA sequencing expression profiling, we have detected mitochondrial abnormalities in young neurons from patients with bipolar disorder by using mitochondrial assays; in addition, using both patch-clamp recording and somatic Ca(2+) imaging, we have observed hyperactive action-potential firing. This hyperexcitability phenotype of young neurons in bipolar disorder was selectively reversed by lithium treatment only in neurons derived from patients who also responded to lithium treatment. Therefore, hyperexcitability is one early endophenotype of bipolar disorder, and our model of iPSCs in this disease might be useful in developing new therapies and drugs aimed at its clinical treatment.

Therapeutic translation of iPSCs for treating neurological disease

Somatic cellular reprogramming is a fast-paced and evolving field that is changing the way scientists approach neurological diseases. For the first time in the history of neuroscience, it is feasible to study the behavior of live neurons from patients with neurodegenerative diseases, such as Alzheimer's and Parkinson's disease, and neuropsychiatric diseases, such as autism and schizophrenia. In this Perspective, we will discuss reprogramming technology in the context of its potential use for modeling and treating neurological and psychiatric diseases and will highlight areas of caution and opportunities for improvement.

How to make a hippocampal dentate gyrus granule neuron

Granule neurons in the hippocampal dentate gyrus (DG) receive their primary inputs from the cortex and are known to be continuously generated throughout adult life. Ongoing integration of newborn neurons into the existing hippocampal neural circuitry provides enhanced neuroplasticity, which plays a crucial role in learning and memory; deficits in this process have been associated with cognitive decline under neuropathological conditions. In this Primer, we summarize the developmental principles that regulate the process of DG neurogenesis and discuss recent advances in harnessing these developmental cues to generate DG granule neurons from human pluripotent stem cells.

Analysis of fusion gene expression in prostate tumors by using single-end reads

Fusion gene expression, a kind of chromosome rearrangement mode, has been strongly linked to prostate cancer diagnosis and prognosis as well as to the Gleason score and the American Joint Committee on Cancer stage assessment. In combination with traditional methods for locating fusion genes and scoring their association with cancer cell growth, proliferation, and invasion through the basement membrane, the emerging high-throughput sequencing technologies offer a panorama of fusion genes in a genome and facilitate the discovery of new fusion modes. We describe here a method for using single-end reads to analyze fusion gene expression in prostate tumors. We obtained the fusion gene expression profiling of prostate tumors, clustered them into several biological pathways, highlighted three "rediscovered" fusion genes (TMPRSS2-ERG, KLK2, and KLK3) and proved the reliability of our method.

Erythrocyte trans-fatty acids, type 2 diabetes and cardiovascular risk factors in middle-aged and older Chinese individuals

AIMS/HYPOTHESIS

Few data are available about intakes and food sources of trans-fatty acids (TFAs) or their associations with cardiometabolic outcomes in Asian people who consume a prudent diet but are experiencing rapid nutritional transitions. We aimed to investigate the relationships between TFA biomarkers and type 2 diabetes and cardiovascular risk factors in Chinese individuals.

METHODS

Erythrocyte fatty acids were measured by gas chromatography among 3,107 men and women (50-70 years) recruited from urban and rural areas in Beijing and Shanghai, China.

RESULTS

Total trans-18:1 and two trans-18:2 isomers were detected and accounted for 0.37% of the total fatty acids in the erythrocytes. Concentrations of TFAs were higher in women than men, and in urban than rural residents. Of the TFAs, trans-18:1, but not trans-18:2, showed a modest association with dairy consumption (β = 0.27), but not with other foods. After adjustment for BMI, social-demographic, lifestyle and dietary factors and other TFAs, erythrocyte trans-18:1 was shown to be associated with a lower risk of type 2 diabetes (OR comparing extreme [first and fourth] quartiles 0.68, 95% CI 0.48, 0.97, p(trend) = 0.02), as well as 20-50% lower odds of central obesity, dyslipidaemia, hyperglycaemia, insulin resistance and chronic inflammation. In contrast, trans-18:2 fatty acids were positively associated with high triacylglycerol (p(trend) < 0.001) and LDL-cholesterol (p(trend) = 0.03) levels, but not with diabetes and other cardiometabolic risk factors.

CONCLUSIONS/INTERPRETATION

Among middle-aged and older Chinese individuals with overall low erythrocyte TFAs levels, trans-18:1 might serve as a marker of dairy intake. Higher trans-18:1 levels were associated with a lower risk of type 2 diabetes, whereas higher trans-18:2 levels were associated with dyslipidaemia.

The effect of recombinant human hyaluronidase on dexamethasone penetration into the posterior segment of the eye after sub-Tenon's injection

PURPOSE

The aim of this study was to investigate the extent if recombinant human hyaluronidase (rhuPH20) can enhance trans-scleral penetration of sub-Tenon's dexamethasone (DM) into the posterior segment of the eye.

METHODS

rhuPH20 was purified from conditioned media through a series of ion exchange, hydrophobic interaction, aminophenylboronate, and hydroxyapatite chromatography to greater than 90% purity based upon specific activity. Only the right eye of each rabbit was injected. The first group (n = 16) received an injection of DM and rhuPH20, whereas the second group (n = 16) received DM only. The eyes were enucleated 1, 2, 3, and 6 h after the injection, and the choroid, retina, vitreous, aqueous, and serum were harvested. DM concentration was assessed by mass spectrometry. Histology (n = 2) and immunohistochemistry (n = 2) was performed to detect toxicity and the presence of the rHuPH20, respectively.

RESULTS

We observed no histopathologic damage to ocular tissues after sub-Tenon's injection. This enzyme significantly increased DM level in the choroid and the retina 3 h after administration. The rise in levels was transient returning to normal levels by 6 h.

CONCLUSIONS

Sub-Tenon's coinjection of rHuPH20 with DM resulted in a general increase in DM levels in ocular tissues and the serum, with significant increase in the choroid and the retina, 3 h after administration.

Hepatitis C virus infection: its role in chronic liver diseases

In order to find out the infectious rate of hepatitis C virus (HCV) among chronic liver diseases, we investigated antibodies against hepatitis C virus and HCVRNA by method of ELISA, RIBA and RT-PCR in 410 patients with chronic liver disease. The prevalence of HCV infection was found to be 4%. Whereas the positive rate of HBsAg and HBV-DNA of these cases was 69% and 58%, respectively. There is no statistical significance between HCV infectious rate of patients with positive and negative HBsAg. The relative low infectious rate of HCV infection among chronic hepatic diseases indicates that HBV infection plays a more important role in causing chronic hepatitis than that of HCV. Thus, special emphasis should be paid to the preventive and therapeutic measures against hepatitis B in China.

[Combination of phentolamine and angelicini in cholestasis and severe type of chronic active hepatitis B]

Among 60 patients with chronic active hepatitis B, 43 were of the severe type, 17 were of cholestasis type. Each type was divided randomly into two groups: therapeutic and control. The former received both conventional supporting therapy and combination of phentolamine (20-30 mg/day) and angelicini (150-450 mg/day). The latter was only treated with conventional supporting therapy. Digital subtraction angiography (DSA) and platelet agglutination test were performed in 10 patients respectively. DSA demonstrated that liver sinusoids were expanded and the vascular bed round the sinusoids were also enlarged in diameter following instillation of phentolamine. It was also shown that angelicini could suppress the second phase of platelet agglutination. These indicated that phentolamine and angelicini could improve the liver microcirculation in different way. The incidence of survival between therapeutic and the control group was 57.14% and 31.82% respectively (P less than 0.05).

Optical fibers for measurement of earth strain

We report on laboratory experiments on single-mode optical fibers for use in measuring earth strain. We have monitored the long-term stability of 25-m long tensioned fibers and found their rates of fractional change in optical path lengths to be no more than 2 x 10(-6)/yr. The optical temperature coefficients for several fibers whose physical lengths were held constant were found to be within 4% of 1.17 x 10(-5) apparent strain/ degrees C. The strain sensitivity (the ratio of observed optical path change to physical path change) was determined to be within 1% of 1.16 for all the fibers tested. Initial field tests indicate that fibers are suitable for earth strain measurements of moderate precision.