Erlotinib attenuates the progression of chronic kidney disease in rats with remnant kidney

Targeting the epidermal growth factor receptor (EGFR/ErbB) for the potential treatment of renal pathologies

Epidermal growth factor receptor (EGFR), which is referred to as ErbB1/HER1, is the prototype of the EGFR family of receptor tyrosine kinases which also comprises ErbB2 (Neu, HER2), ErbB3 (HER3), and ErbB4 (HER4). EGFR, along with other ErbBs, is expressed in the kidney tubules and is physiologically involved in nephrogenesis and tissue repair, mainly following acute kidney injury. However, its sustained activation is linked to several kidney pathologies, including diabetic nephropathy, hypertensive nephropathy, glomerulonephritis, chronic kidney disease, and renal fibrosis. This review aims to provide a summary of the recent findings regarding the consequences of EGFR activation in several key renal pathologies. We also discuss the potential interplay between EGFR and the reno-protective angiotensin-(1-7) (Ang-(1-7), a heptapeptide member of the renin-angiotensin-aldosterone system that counter-regulates the actions of angiotensin II. Ang-(1-7)-mediated inhibition of EGFR transactivation might represent a potential mechanism of action for its renoprotection. Our review suggests that there is a significant body of evidence supporting the potential inhibition of EGFR/ErbB, and/or administration of Ang-(1-7), as potential novel therapeutic strategies in the treatment of renal pathologies. Thus, EGFR inhibitors such as Gefitinib and Erlinotib that have an acceptable safety profile and have been clinically used in cancer chemotherapy since their FDA approval in the early 2000s, might be considered for repurposing in the treatment of renal pathologies.

Renal fibrosis in type 2 cardiorenal syndrome: An update on mechanisms and therapeutic opportunities

Cardiorenal syndrome (CRS) is a state of coexisting heart failure and renal insufficiency in which acute or chronic dysfunction of the heart or kidney lead to acute or chronic dysfunction of the other organ.It was found that renal fibrosis is an important pathological process in the progression of type 2 CRS to end-stage renal disease, and progressive renal impairment accelerates the deterioration of cardiac function and significantly increases the hospitalization and mortality rates of patients. Previous studies have found that Hemodynamic Aiteration, RAAS Overactivation, SNS Dysfunction, Endothelial Dysfunction and Imbalance of natriuretic peptide system contribute to the development of renal disease in the decompensated phase of heart failure, but the exact mechanisms is not clear. Therefore, in this review, we focus on the molecular pathways involved in the development of renal fibrosis due to heart failure and identify the canonical and non-canonical TGF-β signaling pathways and hypoxia-sensing pathways, oxidative stress, endoplasmic reticulum stress, pro-inflammatory cytokines and chemokines as important triggers and regulators of fibrosis development, and summarize the therapeutic approaches for the above signaling pathways, including SB-525334 Sfrp1, DKK1, IMC, rosarostat, 4-PBA, etc. In addition, some potential natural drugs for this disease are also summarized, including SQD4S2, Wogonin, Astragaloside, etc.

Podocyte-Parietal Epithelial Cell Interdependence in Glomerular Development and Disease

Podocytes and parietal epithelial cells (PECs) are among the few principal cell types within the kidney glomerulus, the former serving as a crucial constituent of the kidney filtration barrier and the latter representing a supporting epithelial layer that adorns the inner wall of Bowman's capsule. Podocytes and PECs share a circumscript developmental lineage that only begins to diverge during the S-shaped body stage of nephron formation-occurring immediately before the emergence of the fully mature nephron. These two cell types, therefore, share a highly conserved gene expression program, evidenced by recently discovered intermediate cell types occupying a distinct spatiotemporal gene expression zone between podocytes and PECs. In addition to their homeostatic functions, podocytes and PECs also have roles in kidney pathogenesis. Rapid podocyte loss in diseases, such as rapidly progressive GN and collapsing and cellular subtypes of FSGS, is closely allied with PEC proliferation and migration toward the capillary tuft, resulting in the formation of crescents and pseudocrescents. PECs are thought to contribute to disease progression and severity, and the interdependence between these two cell types during development and in various manifestations of kidney pathology is the primary focus of this review.

Matrix Metalloproteinase-10 in Kidney Injury Repair and Disease

Matrix metalloproteinase-10 (MMP-10) is a zinc-dependent endopeptidase with the ability to degrade a broad spectrum of extracellular matrices and other protein substrates. The expression of MMP-10 is induced in acute kidney injury (AKI) and chronic kidney disease (CKD), as well as in renal cell carcinoma (RCC). During the different stages of kidney injury, MMP-10 may exert distinct functions by cleaving various bioactive substrates including heparin-binding epidermal growth factor (HB-EGF), zonula occludens-1 (ZO-1), and pro-MMP-1, -7, -8, -9, -10, -13. Functionally, MMP-10 is reno-protective in AKI by promoting HB-EGF-mediated tubular repair and regeneration, whereas it aggravates podocyte dysfunction and proteinuria by disrupting glomerular filtration integrity via degrading ZO-1. MMP-10 is also involved in cancerous invasion and emerges as a promising therapeutic target in patients with RCC. As a secreted protein, MMP-10 could be detected in the circulation and presents an inverse correlation with renal function. Due to the structural similarities between MMP-10 and the other MMPs, development of specific inhibitors targeting MMP-10 is challenging. In this review, we summarize our current understanding of the role of MMP-10 in kidney diseases and discuss the potential mechanisms of its actions.

The Effect of Single-Dose Ougan Juice Application on the Pharmacokinetics of Erlotinib

The aim of our study was to investigate the effects of single-dose Ougan (Citrus reticulata cv. Suavissima) juice application on the pharmacokinetics of erlotinib in vivo. Twelve Sprague-Dawley rats were randomly divided into the Ougan juice and control groups (n = 6 each). The rats were given a single dose of 1 mL/100 g Ougan juice or 1 mL/100 g normal saline (NS) by intragastric administration, followed by a single oral administration of 20 mg/kg erlotinib. The plasma concentration of erlotinib in rats was determined using ultra performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). Erlotinib-d6 was used as the internal standard for chromatographic analysis on the UPLC BEH C18 analysis column (2.1 mm × 50 mm, 1.7 μm). The mobile phase was composed of acetonitrile and 0.1% formic acid eluting by gradient. Different pharmacokinetic (PK) parameters of erlotinib were calculated. The Ougan juice promoted the absorption of erlotinib and reduced the clearance of the drug. The area under the curve of erlotinib in the single-dose Ougan juice pretreatment group was approximately 1.87 times higher, and the maximum blood concentration (Cmax) was approximately 1.34 times higher than that in the control group. The mean residence time of erlotinib in the Ougan juice group was larger, and the clearance rate was smaller than those in the control group; the difference was statistically significant (P < 0.05). Ougan juice affected the PK spectrum of erlotinib in rats by improving the bioavailability of the drug and significantly increasing its plasma concentration.

Reno-protective effect of IL-34 inhibition on cisplatin-induced nephrotoxicity in mice

INTRODUCTION

Interleukin-34 (IL-34) shares a receptor (cFMS) with colony stimulating factor-1 (CSF-1), and these two ligands mediate macrophage proliferation. However, in contrast to CSF-1, the influence of IL-34 on tubular epithelial cells (TECs) injury remains unclear. We investigated the physiological effects of IL-34 on TEC damage caused by cisplatin nephrotoxicity (CP-N).

METHODS

Mice were administered anti-mouse IL-34 antibody (anti-IL-34 Ab; 400 ng/kg) or vehicle from 1 day before and up to 2 days after CP-N induction. In vitro, mouse renal proximal TECs (MRPTEpiC) were cultured to analyze the inhibitory effects of IL-34 on CP-induced TEC apoptosis.

RESULTS

Compared to vehicle treatment, anti-IL-34 Ab treatment significantly suppressed the intra-renal expression of IL-34 and its two receptors, cFMS and PTP-ζ, and significantly improved renal function, ameliorated tubulointerstitial injury, suppressed macrophage infiltration, and reduced apoptotic cell numbers in CP-N mice. It also significantly reduced the renal transcript levels of Kim-1, MIP-1/CCL3, TNF-α, and Bax in CP-N mice. Furthermore, anti-IL-34 Ab-treated CP-N mice showed less renal infiltration of F4/80+TNF-α+ cells. In vitro, stimulation with CP induced the expression of IL-34 and its two receptors in MRPTEpiC. Anti-IL-34 Ab treatment significantly suppressed CP-induced Bax expression with the degradation of ERK1/2 phosphorylation in damaged MRPTEpiC.

CONCLUSIONS

IL-34 secreted from damaged TECs appeared to be involved in the progression of CP-N. Inhibition of IL-34 with neutralizing antibody directly prevented CP-induced TEC apoptosis by inhibiting the phosphorylation of ERK 1/2. Blocking of IL-34 appears to suppress the proliferation of cytotoxic macrophages, which indirectly attenuates CP-N. Thus, IL-34 represents a potential therapeutic target for TEC injury, and the inhibition of IL-34 might have a reno-protective effect.

The Blockade of TACE-Dependent EGF Receptor Activation by Losartan-Erlotinib Combination Attenuates Renal Fibrosis Formation in 5/6-Nephrectomized Rats Under Vitamin D Deficiency

Chronic kidney disease (CKD) has been considered a major public health issue. In addition to cardiovascular diseases and infections, hypovitaminosis D has been considered a non-traditional aggravating factor for CKD progression. Interstitial fibrosis is a hallmark of CKD strongly correlated with deterioration of renal function. Transforming growth factor β (TGF-β) is the major regulatory profibrotic cytokine in CKD. Many injurious stimuli converge on the TGF-β pathway, which has context-dependent pleiotropic effects and interacts with several related renal fibrosis formation (RFF) pathways. Epidermal growth factor receptor (EGFR) is critically involved in CKD progression, exerting a pathogenic role in RFF associated with TGF-β-related fibrogenesis. Among others, EGFR pathway can be activated by a disintegrin and a metalloproteinase known as tumor necrosis factor α-converting enzyme (TACE). Currently no effective therapy is available to completely arrest RFF and slow the progression of CKD. Therefore, we investigated the effects of a double treatment with losartan potassium (L), an AT1R antagonist, and the tyrosine kinase inhibitor erlotinib (E) on the alternative pathway of RFF related to TACE-dependent EGFR activation in 5/6-nephrectomized rats under vitamin D deficiency (D). During the 90-day protocol, male Wistar rats under D, were submitted to 5/6 nephrectomy (N) on day 30 and randomized into four groups: N+D, no treatment; N+D+L, received losartan (50 mg/kg/day); N+D+E, received erlotinib (6 mg/kg/day); N+D+L+E received losartan+erlotinib treatment. N+D+L+E data demonstrated that the double treatment with losartan+erlotinib not only blocked the TACE-dependent EGF receptor activation but also prevented the expression of TGF-β, protecting against RFF. This renoprotection by losartan+erlotinib was corroborated by a lower expression of ECM proteins and markers of phenotypic alteration as well as a lesser inflammatory cell infiltrate. Although erlotinib alone has been emerging as a renoprotective drug, its association with losartan should be considered as a potential therapeutic strategy on the modulation of RFF.

Eye, hepatobiliary, and renal disorders of erlotinib in patients with non-small-cell lung cancer: A meta-analysis

Background

Erlotinib is an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors used to treat EGFR mutation positive non-small-cell lung cancer (NSCLC). Skin rash and diarrhea are well-known and common adverse events in patients receiving erlotinib, whereas other adverse events, including eye, liver, or renal disorders have not been evaluated adequately. This meta-analysis aimed to evaluate the ocular, hepatobiliary, and renal toxicities of erlotinib in patients with NSCLC cancers.

Methods

In total, sixty studies were assessed, and the results of the included studies were quantitatively integrated using meta-analysis. The incidence of ocular, hepatobiliary (alanine aminotransferase [ALT] and bilirubin elevations; other hepatic adverse events), and renal adverse events were estimated. Additionally, the erlotinib-treated groups and the control groups (placebo or other treatment) were compared with respect to ocular disorders and ALT elevation. The study protocol has been registered in the International Prospective Register for Systematic Reviews (PROSPERO) CRD42018093758.

Results

The overall incidence of ocular disorders was 3.30% (95% confidence interval [CI] 2.20%–5.00%). The incidence of ALT elevation, bilirubin elevation, and other hepatobiliary disorders was 6.40% (95% CI 3.90%–10.4%), 3.80% (95% CI 2.30%–6.10%), and 1.00% (95% 0.60%–1.80%), respectively. The incidence of renal disorder was 3.10% (95% CI 1.90%–5.00%). The risk of ocular toxicity in the erlotinib treatment group was significantly increased (risk ratio = 2.91; 95% CI 1.70–4.98) compared to that in the control group. ALT elevation was not significantly different between the two groups.

Conclusion

Based on the results, careful monitoring of ocular toxicity in patients receiving erlotinib should be recommended and closer monitoring of hepatic toxicity should be also recommended in patients with liver-related risk factors.

Erlotinib can halt adenine induced nephrotoxicity in mice through modulating ERK1/2, STAT3, p53 and apoptotic pathways

Renal fibrosis is a failed regenerative process that facilitates chronic kidney disease progression. The current study was designed to study the effect of erlotinib, a receptor tyrosine kinase inhibitor, on the progression of renal fibrosis. The study included four groups of mice: control group; adenine group: received adenine (0.2% w/w) daily with food for 4 weeks; erlotinib group: received 80 mg/kg/day erlotinib orally (6 ml/kg/day, 1.3% w/v suspension in normal saline 0.9%) for 4 weeks; adenine + erlotinib group: received adenine and erlotinib concurrently. Kidney function and antioxidant biomarkers were measured. Renal expression of Bcl2 and p53 and histopathological changes (tubular injury and renal fibrosis) were scored. Renal tissue levels of transforming growth factor-β₁, p-ERK1/2 and p-STAT3 were measured. Results obtained showed significant decrease (P < 0.001) in serum creatinine, urea and uric acid in erlotinib + adenine group. Level of malondialdehyde was decreased significantly (P < 0.001) while reduced glutathione and catalase levels were increased (P < 0.01) by erlotinib concurrent administration. Erlotinib markedly reduced fibrosis and tubular injury and decreased TGF-β1, p-ERK1/2 and p-STAT3 (P < 0.5). In addition, expression level of Bcl-2 was elevated (P < 0.001) while that of p53-was reduced compared to adenine alone. Erlotinib can attenuate renal fibrosis development and progression through anti-fibrotic, antioxidant and anti-apoptotic pathways.

Complete remission of membranous nephropathy in a patient with lung adenocarcinoma treated with erlotinib

WHAT IS KNOWN AND OBJECTIVE

Membranous nephrotic syndrome is one of the most commonly seen paraneoplastic nephropathies.

CASE DESCRIPTION

We describe a 59-year-old man who was referred with massive unilateral pleural effusion and was subsequently diagnosed with lung adenocarcinoma. Routine physical and laboratory examinations revealed lower limb oedema, hypoproteinaemia and proteinuria. Examination of a kidney biopsy aspirate confirmed the diagnosis of membranous nephropathy. Aetiological investigations of the kidney pathology ruled out causes other than paraneoplastic nephropathy. Since an epidermal growth factor receptor mutation was identified by analysis of the exfoliated tumour cells in pleural effusion, erlotinib was administered, without further treatment of the membranous nephropathy. Upon control of the patient's lung cancer, the membranous nephropathy completely disappeared, and at the time of this writing, had not recurred over a 4-year follow-up period.

WHAT IS NEW AND CONCLUSION

For patients with EGFR-mutation-positive lung adenocarcinoma associated with paraneoplastic membranous nephropathy, erlotinib might serve as a treatment option for both the tumour and the membranous nephropathy.

Mesangial Cells and Renal Fibrosis

The main cellular constituents in glomerular mesangium are mesangial cells, which account for approximately 30-40% of the total cells in the glomerulus. Together with the mesangial matrix, mesangial cells form the glomerular basement membrane (GBM) in the glomerulus, whose main function is to perform the filtration. Under the pathologic conditions, mesangial cells are activated, leading to hyperproliferation and excess extracellular matrix (ECM). Moreover, mesangial cells also secrete several kinds of inflammatory cytokines, adhesion molecules, chemokines, and enzymes, all of which participate in the process of renal glomerular fibrosis. During the past years, researchers have revealed the roles of mesangial cells and the associated signal pathways involved in renal fibrosis. In this section, we will discuss how mesangial cells are activated and its contributions to renal fibrosis, as well as the molecular mechanisms and novel anti-fibrotic agents. Full understanding of the contributions of mesangial cells to renal fibrosis will benefit the clinical drug developing.

IL-22 sustains epithelial integrity in progressive kidney remodeling and fibrosis

IL-22, a member of the IL-10 cytokine family, accelerates tubule regeneration upon acute kidney injury, hence we speculated on a protective role also in chronic kidney disease. We quantified intrarenal IL-22 expression after unilateral ureteral (UUO) in wild-type mice and performed UUO in IL-22 knock-out animals. Obstruction phenotypic differences between IL22+/+ and IL22-/- mice were assessed by histology, immunohistochemistry, immunofluorescence as well as western blotting and reverse-transcriptase quantitative PCR ex vivo. Additionally, we performed in vitro experiments using both murine and human tubular cells to characterize IL-22 effects in epithelial healing. We found increasing IL-22 positivity in infiltrating immune cells over time upon UUO in wild-type mice. UUO in IL22-/- mice caused more tubular cell injury as defined by TUNEL positive cells and loss of tetragonolobus lectin staining. Instead, tubular dilation, loss of CD31+ perivascular capillaries, and interstitial fibrosis were independent of the Il22 genotype as assessed by standard histology, immunostaining, and mRNA expression profiling. In vitro experiments showed that recombinant human IL-22 significantly enhanced human tubular epithelial cell proliferation and wound closure upon mechanical injury, and electric cell-substrate impedance sensing studies revealed that recombinant IL-22 sustained tubular epithelial barrier function upon injury. In contrast, IL-22 had no such direct effects on human fibroblasts. Together, in progressive kidney remodeling upon UUO, infiltrating immune cells secrete IL-22, which augments tubular epithelial integrity and epithelial barrier function, but does not affect vascular rarefaction or fibrogenesis. We conclude that IL-22 could represent a molecular target to specifically modulate tubular atrophy.