This study investigated whether oncogenic and tumor-suppressive gene mutations are involved in the differential outcomes of patients with rectal carcinoma receiving neoadjuvant chemoradiotherapy ...(nCRT). Genomic DNA was obtained from formalin-fixed paraffin-embedded (FFPE) specimens of patients with rectal carcinoma who received a complete nCRT course. Gene mutation status was examined in specimens from patients before and after nCRT by using the AmpliSeq platform. Our data revealed that the nonsynonymous p53, APC, KRAS, CDKN2A, and EGFR mutations were observed in 93.1%, 65.5%, 48.6%, and 31% of the patients with rectal adenocarcinoma, respectively. BRAF, FBXW7, PTEN, and SMAD4 mutations were observed in 20.7% of patients with rectal carcinoma. The following 12 gene mutations were observed more frequently in the patients exhibiting a complete response than in those demonstrating a poor response before nCRT: ATM, BRAF, CDKN2A, EGFR, FLT3, GNA11, KDR, KIT, PIK3CA, PTEN, PTPN11, SMAD4, and TP53. In addition, APC, BRAF, FBXW7, KRAS, SMAD4, and TP53 mutations were retained after nCRT. Our results indicate a complex mutational profile in rectal carcinoma, suggesting the involvement of BRAF, SMAD4, and TP53 genetic variants in the outcomes of patients with nCRT.
Indoxyl sulfate (IS) is accumulated during severe renal insufficiency and known for its nephrotoxic properties. Transient receptor potential vanilloid 1 (TRPV1) is present in the kidney and acts as a ...renal sensor. However, the mechanism underlying IS-mediated renal tubular damage in view of TRPV1 is lacking. Here, we demonstrated that TRPV1 was expressed in tubular cells of Lilly Laboratories cell-porcine kidney 1 (LLC-PK
) and Madin-Darby canine kidney cells (MDCK). IS treatment in both cells exhibited tubular damage with increased LDH release and reduced cell viability in dose- and time-dependent manners. MDCK, however, was more vulnerable to IS. We, therefore, investigated MDCK cells to explore a more detailed mechanism. Interestingly, IS-induced tubular damage was markedly attenuated in the presence of selective TRPV1 blockers. IS showed no effect on TRPV1 expression but significantly increased arachidonate 12-lipoxygenase (ALOX12) protein, mRNA expression, and 12(
)-hydroxyeicosatetraenoic acid (12(
)-HETE) amounts in a dose-dependent manner, indicating that the ALOX12/12(
)-HETE pathway induced TRPV1 hyperfunction in IS-mediated tubulotoxicity. Blockade of ALOX12 by cinnamyl-3,4-dihydroxy-α-cyanocinnamate or baicalein attenuated the effects of IS. Since aryl hydrocarbon receptor (AhR) activation after IS binding is crucial in mediating cell death, here, we found that the AhR blockade not only ameliorated tubular damage but also attenuated ALOX12 expression and 12(
)-HETE production caused by IS. The uremic toxic adsorbent AST-120, however, showed little effect on ALOX12 and 12(
)-HETE, as well as IS-induced cell damage. These results clearly indicated that IS activated AhR and then upregulated ALOX12, and this induced endovanilloid 12(
)-HETE synthesis and contributed to TRPV1 hyperfunction in IS-treated tubular cells. Further study on TRPV1 may attenuate kidney susceptibility to the functional loss of end-stage kidney disease via IS.
The coronavirus disease 2019 (COVID-19) pandemic has claimed the lives of millions of people around the world. Severe vitamin D deficiency can increase the risk of death in people with COVID-19. ...There is growing evidence that acute kidney injury (AKI) is common in COVID-19 patients and is associated with poorer clinical outcomes. The kidney effects of SARS-CoV-2 are directly mediated by angiotensin 2-converting enzyme (ACE2) receptors. AKI is also caused by indirect causes such as the hypercoagulable state and microvascular thrombosis. The increased release of soluble urokinase-type plasminogen activator receptor (suPAR) from immature myeloid cells reduces plasminogen activation by the competitive inhibition of urokinase-type plasminogen activator, which results in low plasmin levels and a fibrinolytic state in COVID-19. Frequent hypercoagulability in critically ill patients with COVID-19 may exacerbate the severity of thrombosis. Versican expression in proximal tubular cells leads to the proliferation of interstitial fibroblasts through the C3a and suPAR pathways. Vitamin D attenuates the local expression of podocyte uPAR and decreases elevated circulating suPAR levels caused by systemic inflammation. This decrease preserves the function and structure of the glomerular barrier, thereby maintaining renal function. The attenuated hyperinflammatory state reduces complement activation, resulting in lower serum C3a levels. Vitamin D can also protect against COVID-19 by modulating innate and adaptive immunity, increasing ACE2 expression, and inhibiting the renin–angiotensin–aldosterone system. We hypothesized that by reducing suPAR levels, appropriate vitamin D supplementation could prevent the progression and reduce the severity of AKI in COVID-19 patients, although the data available require further elucidation.
Heme oxygenase one (HO-1) is considered a poor prognostic factor for survival in patients with severe-to-critical coronavirus disease (COVID-19), but the clinical correlation between heme catabolism ...biomarkers and COVID-19-related sepsis is unknown. The etiopathogenetic hypothesis of HO-1 response during sepsis in patients with poor prognosis should be clarified. This study aimed to investigate sepsis development within 48 h following moderate-to-critical COVID-19 and examined heme/HO-1 catabolism biomarkers associated with sepsis. We also studied the HO-1 and traditional prognostic factors for predicting survival in patients with COVID-19.
This retrospective observational study included patients unvaccinated for COVID-19 with moderate-to-critical COVID-19 (n = 156) who had been admitted to Taipei Tzu Chi Hospital in 2021. All COVID-19 patients were diagnosed by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcriptase polymerase chain reaction. For analysis of heme catabolism in SARS-CoV-2-induced sepsis, we excluded patients with co-infection and severe anemia. Heme catabolism biomarkers were compared between groups of patients with COVID-19 and sepsis (sepsis) and those with COVID-19 without sepsis (no sepsis), and a control group comprising 100 healthy individuals. All clinical and laboratory data were collected retrospectively and blood specimens were collected from Biobank. Multivariable logistic regression analysis was used to compare all variables between the sepsis and no-sepsis groups. Cox regression analysis was used to determine predictors of survival in patients with COVID-19.
There were 71 and 85 patients with and without sepsis, respectively. Heme and HO-1 levels differed significantly between the sepsis, no sepsis, and control groups. In multivariate analysis, confusion, blood urea nitrogen, respiration, blood pressure in patients aged > 65 years (CURB-65) (adjusted odds ratio aOR 5.331, 95% confidence interval CI 2.587-10.987; p < 0.001), albumin (aOR 0.139, 95% CI 0.003-0.636; p = 0.01), D-dimer (aOR 1.001, 95% CI 1.000-1.002; p = 0.032), and HO-1 (aOR 1.116, 95% CI 1.055-1.180; p < 0.001) were significantly associated with 48-h sepsis episodes after adjusting for other confounding factors. HO-1 levels were also significantly associated with 48-h Sequential Organ Failure Assessment Score (SOFA) scores. However, HO-1 did not significantly increase the hazard of in-hospital mortality in moderate-to-critical COVID-19 by Cox regression analysis.
HO-1 levels increased with sepsis development within 48 h of admission for COVID-19 after adjusting for other risk factors, but no significant association was observed between HO-1 and COVID-19 mortality. We suppose that HO-1 may have protective effect in early sepsis, but further clinical multicenter prospective studies are needed.
Indoxyl sulfate (IS), a uremic toxin, causes chronic kidney disease (CKD) progression via its tubulotoxicity. After cellular uptake, IS directly induces apoptotic and necrotic cell death of tubular ...cells. Additionally, IS increases oxidative stress and decreases antioxidant capacity, which are associated with tubulointerstitial injury. Injured tubular cells are a major source of transforming growth factor-β1 (TGF-β1), which induces myofibroblast transition from residual renal cells in damaged kidney, recruits inflammatory cells and thereby promotes extracellular matrix deposition in renal fibrosis. Moreover, IS upregulates signal transducers and activators of transcription 3 phosphorylation, followed by increases in TGF-β1, monocyte chemotactic protein-1 and α-smooth muscle actin production, which participate in interstitial inflammation, renal fibrosis and, consequently, CKD progression. Clinically, higher serum IS levels are independently associated with renal function decline and predict all-cause mortality in CKD. The poor removal of serum IS in conventional hemodialysis is also significantly associated with all-cause mortality and heart failure incidence in end-stage renal disease patients. Scavenging the IS precursor by AST-120 can markedly reduce tubular IS staining that attenuates renal tubular injury, ameliorates IS-induced oxidative stress and rescues antioxidant glutathione activity in tubular epithelial cells, thereby providing a protective role against tubular injury and ultimately retarding renal function decline.
Vascular calcification, which involves the deposition of calcifying particles within the arterial wall, is mediated by atherosclerosis, vascular smooth muscle cell osteoblastic changes, adventitial ...mesenchymal stem cell osteoblastic differentiation, and insufficiency of the calcification inhibitors. Recent observations implied a role for mesenchymal stem cells and endothelial progenitor cells in vascular calcification. Mesenchymal stem cells reside in the bone marrow and the adventitial layer of arteries. Endothelial progenitor cells that originate from the bone marrow are an important mechanism for repairing injured endothelial cells. Mesenchymal stem cells may differentiate osteogenically by inflammation or by specific stimuli, which can activate calcification. However, the bioactive substances secreted from mesenchymal stem cells have been shown to mitigate vascular calcification by suppressing inflammation, bone morphogenetic protein 2, and the Wingless-INT signal. Vitamin D deficiency may contribute to vascular calcification. Vitamin D supplement has been used to modulate the osteoblastic differentiation of mesenchymal stem cells and to lessen vascular injury by stimulating adhesion and migration of endothelial progenitor cells. This narrative review clarifies the role of mesenchymal stem cells and the possible role of vitamin D in the mechanisms of vascular calcification.
Diabetic macular edema (DME) is the most common cause of vision loss among patients with diabetes mellitus (DM), rendering it an important growing challenge in ophthalmology. In the past decades, the ...management strategies for DME had a few paradigm shifts, and the advent of an expanding number of anti-vascular endothelial growth factor (VEGF) agents also calls for an in-depth examination of the currently available evidence. This article was composed with the intention to provide recommendations for practicing clinicians to improve the management and, through it the outcomes of DME. Drawing from current guideline recommendations, clinical trial findings and local clinical experiences, these consensus recommendations for the management of DME were formed by an expert panel through iterations of discussion and voting. First, the treatment goal of DME is to achieve best visual outcome with edema improvement while minimizing treatment burden. Second, anti-VEGF therapy should be considered as the first-line treatment for patients with center-involving DME causing vision loss. Baseline visual acuity (VA) and central subfield thickness (CST) should be taken into consideration when choosing anti-VEGF agents. Third, early intensive anti-VEGF therapy (at least 3 monthly doses) is important for better patients’ VA and anatomical improvement. In non-responders who have already been treated with 3-5 injections of anti-VEGF agents, it is reasonable to switch to other modalities, such as steroids. Finally, for the follow-up phase, fixed or individualized dosing should be considered based on VA and OCT.
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