Kamebakaurin Suppresses Antigen-Induced Mast Cell Activation by Inhibition of FcεRI Signaling Pathway.

INTRODUCTION: Kamebakaurin is an active constituent of both Rabdosia japonica and Rabdosia excisa, which are utilized in Chinese traditional medicine for improving symptoms in patients with allergies. We investigated the molecular mechanisms of the anti-allergic effects of kamebakaurin using BMMCs. METHODS: The degranulation ratio, histamine release, and the interleukin (IL)-4, leukotriene B4 (LTB4), and cysteinyl leukotriene productions on antigen-triggered BMMC were investigated. Additionally, the effects of kamebakaurin on signal transduction proteins were examined by Western blot and binding to the Syk and Lyn kinase domain was calculated. The effects of kamebakaurin on antigen-induced hyperpermeability were investigated using mouse model. RESULTS: At 10 µm, kamebakaurin partially inhibited degranulation, histamine release, and IL-4 production. At 30 µm, kamebakaurin partially reduced LTB4 and cysteinyl leukotriene productions and suppressed degranulation, histamine release, and IL-4 production. Phosphorylation of both Syk Y519/520 and its downstream protein, Gab2, was reduced by kamebakaurin, and complete inhibition was observed with 30 µm kamebakaurin. In contrast, phosphorylation of Erk was only partially inhibited, even in the presence of 30 µm kamebakaurin. Syk Y519/520 is known to be auto-phosphorylated via intramolecular ATP present in its own ATP-binding site, and this auto-phosphorylation triggers degranulation, histamine release, and IL-4 production. Docking simulation study indicated kamebakaurin blocked ATP binding to the ATP-binding site in Syk. Therefore, inhibition of Syk auto-phosphorylation by kamebakaurin binding to the Syk ATP-binding site appeared to cause a reduction of histamine release and IL-4 production. Kamebakaurin inhibited antigen-induced vascular hyperpermeability in a dose-dependent fashion but did not reduce histamine-induced vascular hyperpermeability. CONCLUSION: Kamebakaurin ameliorates allergic symptoms via inhibition of Syk phosphorylation; thus, kamebakaurin could be a lead compound for the new anti-allergic drug.

Protective role of podocyte autophagy against glomerular endothelial dysfunction in diabetes.

To examine the cell-protective role of podocyte autophagy against glomerular endothelial dysfunction in diabetes, we analyzed the renal phenotype of tamoxifen (TM)-inducible podocyte-specific Atg5-deficient (iPodo-Atg5-/-) mice with experimental endothelial dysfunction. In both control and iPodo-Atg5-/- mice, high fat diet (HFD) feeding induced glomerular endothelial damage characterized by decreased urinary nitric oxide (NO) excretion, collapsed endothelial fenestrae, and reduced endothelial glycocalyx. HFD-fed control mice showed slight albuminuria and nearly normal podocyte morphology. In contrast, HFD-fed iPodo-Atg5-/- mice developed massive albuminuria accompanied by severe podocyte injury that was observed predominantly in podocytes adjacent to damaged endothelial cells by scanning electron microscopy. Although podocyte-specific autophagy deficiency did not affect endothelial NO synthase deficiency-associated albuminuria, it markedly exacerbated albuminuria and severe podocyte morphological damage when the damage was induced by intravenous neuraminidase injection to remove glycocalyx from the endothelial surface. Furthermore, endoplasmic reticulum stress was accelerated in podocytes of iPodo-Atg5-/- mice stimulated with neuraminidase, and treatment with molecular chaperone tauroursodeoxycholic acid improved neuraminidase-induced severe albuminuria and podocyte injury. In conclusion, podocyte autophagy plays a renoprotective role against diabetes-related structural endothelial damage, providing an additional insight into the pathogenesis of massive proteinuria in diabetic nephropathy.

Protein O-GlcNAcylation Is Essential for the Maintenance of Renal Energy Homeostasis and Function via Lipolysis during Fasting and Diabetes.

BACKGROUND: Energy metabolism in proximal tubular epithelial cells (PTECs) is unique, because ATP production largely depends on lipolysis in both the fed and fasting states. Furthermore, disruption of renal lipolysis is involved in the pathogenesis of diabetic tubulopathy. Emerging evidence suggests that protein O-GlcNAcylation, an intracellular nutrient-sensing system, may regulate a number of metabolic pathways according to changes in nutritional status. Although O-GlcNAcylation in PTECs has been demonstrated experimentally, its precise role in lipolysis in PTECs is unclear. METHODS: To investigate the mechanism of renal lipolysis in PTECs-specifically, the role played by protein O-GlcNAcylation-we generated mice with PTECs deficient in O-GlcNAc transferase (Ogt). We analyzed their renal phenotypes during ad libitum feeding, after prolonged fasting, and after mice were fed a high-fat diet for 16 weeks to induce obesity and diabetes. RESULTS: Although PTEC-specific Ogt-deficient mice lacked a marked renal phenotype during ad libitum feeding, after fasting 48 hours, they developed Fanconi syndrome-like abnormalities, PTEC apoptosis, and lower rates of renal lipolysis and ATP production. Proteomic analysis suggested that farnesoid X receptor-dependent upregulation of carboxylesterase-1 is involved in O-GlcNAcylation's regulation of lipolysis in fasted PTECs. PTEC-specific Ogt-deficient mice with diabetes induced by a high-fat diet developed severe tubular cell damage and enhanced lipotoxicity. CONCLUSIONS: Protein O-GlcNAcylation is essential for renal lipolysis during prolonged fasting and offers PTECs significant protection against lipotoxicity in diabetes.

Overexpression of acetyl CoA carboxylase ß exacerbates podocyte injury in the kidney of streptozotocin-induced diabetic mice.

A single nucleotide polymorphism (SNP) within the acetyl CoA carboxylase (ACC) ß gene (ACACB), rs2268388, has been shown to be associated with susceptibility to development of proteinuria in patients with type 2 diabetes. To investigate the biological roles of ACCß in the pathogenesis of diabetic nephropathy, we examined the effects of overexpression of ACACB using podocyte-specific ACACB-transgenic mice or ACACB-overexpressing murine podocytes. Podocyte-specific ACACB-transgenic mice or littermate mice were treated with streptozotocin (STZ) to induce diabetes, and 12 weeks after induction of diabetes, we examined the expression of podocyte markers to evaluate the degree of podocyte injury in these mice. We also examined the effects of ACCß on podocyte injury in ACACB- or LacZ-overexpressing murine podocytes. Podocyte-specific ACACB overexpression did not cause visible podocyte injury in non-diabetic mice. In STZ-induced diabetic mice, ACACB-transgenic mice showed a significant increase in urinary albumin excretion, accompanied by decreased synaptopodin expression and podocin mislocalization in podocytes, compared with wild-type mice. In cultured murine podocytes, overexpression of ACACB significantly decreased synaptopodin expression and reorganized stress fibers under high glucose conditions, but not in normal glucose conditions. The decrease of synaptopodin expression and reorganized stress fibers observed in ACACB overexpressing cells cultured under high glucose conditions was reversed by a treatment of 5-aminoimidazole-4-carboxamide-1-beta-4-ribofuranoside (AICAR), activator of AMP-activated protein kinase (AMPK). The excess of ACCß might contribute to exacerbation of podocyte injury in the kidney of an animal model for diabetes mellitus, and the AMPK/ACCß pathway may be a novel therapeutic target for the prevention of diabetes-related podocyte injury.

O-linked ß-N-acetylglucosamine modification of proteins is essential for foot process maturation and survival in podocytes.

BACKGROUND: O-linked ß- N -acetylglucosamine modification O-GlcNAcylation) is a post-translational modification of intracellular proteins, serving as a nutrient sensor. Growing evidence has demonstrated its physiological and pathological importance in various mammalian tissues. This study examined the physiological role of O-GlcNAcylation in podocyte function and development. METHODS: O-GlcNAc transferase (Ogt) is a critical enzyme for O-GlcNAcylation and resides on the X chromosome. To abrogate O-GlcNAcylation in podocytes, we generated congenital and tamoxifen (TM)-inducible podocyte-specific Ogt knockout mice (Podo-Ogt y/- and TM-Podo-Ogt y/- , respectively) and analyzed their renal phenotypes. RESULTS: Podo-Ogt y/- mice showed normal podocyte morphology at birth. However, they developed albuminuria at 8 weeks of age, increasing progressively until age 32 weeks. Glomerular sclerosis, proteinuria-related tubulointerstitial lesions and markedly altered podocyte foot processes, with decreased podocin expression, were observed histologically in 32-week-old Podo-Ogt y/- mice. Next, we induced adult-onset deletion of the Ogt gene in podocytes by TM injection in 8-week-old TM-Podo-Ogt y/- mice. In contrast to Podo-Ogt y/- mice, the induced TM-Podo-Ogt y/- mice did not develop albuminuria or podocyte damage, suggesting a need for O-GlcNAcylation to form mature foot processes after birth. To test this possibility, 3-week-old Podo-Ogt y/- mice were treated with Bis-T-23, which stimulates actin-dependent dynamin oligomerization, actin polymerization and subsequent foot process elongation in podocytes. Albuminuria and podocyte damage in 16-week-old Podo-Ogt y/- mice were prevented by Bis-T-23 treatment. CONCLUSIONS: O-GlcNAcylation is necessary for maturation of podocyte foot processes, particularly after birth. Our study provided new insights into podocyte biology and O-GlcNAcylation.

Efficacy of reduced dose of pegfilgrastim in Japanese breast cancer patients receiving dose-dense doxorubicin and cyclophosphamide therapy.

BACKGROUND: This retrospective study aimed to evaluate the efficacy of a 3.6-mg dose of pegfilgrastim for primary prophylaxis in Japanese breast cancer patients receiving dose-dense chemotherapy. METHODS: Patients treated with adjuvant or neoadjuvant chemotherapy for early-stage breast cancer at the Tokyo-West Tokushukai Hospital were included in this analysis. Because 6 mg pegfilgrastim has not yet been approved for use in Japan, we compared the outcomes of a dose-dense doxorubicin and cyclophosphamide regimen plus 3.6 mg pegfilgrastim support with a conventional dose epirubicin and cyclophosphamide regimen. The incidence of febrile neutropenia, relative dose intensity, dose delay, dose reduction, regimen change and hospitalization because of neutropenia were assessed. RESULTS: From November 2013 to March 2016, 97 patients with stage I-III invasive breast cancer were analyzed (dose-dense doxorubicin and cyclophosphamide plus 3.6-mg pegfilgrastim group, n  =  41; epirubicin and cyclophosphamide group, n  =  56; median ages, 49.0 and 48.5 years, respectively). Febrile neutropenia occurred during the first chemotherapy cycle in 7 of 56 patients (12.5%) in the epirubicin and cyclophosphamide group and 0 of 41 patients in the dose-dense doxorubicin and cyclophosphamide group (P  =  0.02). The average relative dose intensities were 97.9% and 96.8%, respectively (P  =  0.28), with corresponding dose delay rates of 4.9% (2/41) and 16.1% (9/56), respectively (P  =  0.11) and dose reduction rates of 0% (0/41) and 7.1% (4/56), respectively (P  =  0.16). CONCLUSIONS: Our results indicate the efficacy of a 3.6-mg pegfilgrastim dose for the primary prevention of febrile neutropenia in dose-dense doxorubicin- and cyclophosphamide-treated Japanese breast cancer patients.

Stearoyl-CoA Desaturase-1 Protects Cells against Lipotoxicity-Mediated Apoptosis in Proximal Tubular Cells.

Saturated fatty acid (SFA)-related lipotoxicity is a pathogenesis of diabetes-related renal proximal tubular epithelial cell (PTEC) damage, closely associated with a progressive decline in renal function. This study was designed to identify a free fatty acid (FFA) metabolism-related enzyme that can protect PTECs from SFA-related lipotoxicity. Among several enzymes involved in FFA metabolism, we identified stearoyl-CoA desaturase-1 (SCD1), whose expression level significantly decreased in the kidneys of high-fat diet (HFD)-induced diabetic mice, compared with non-diabetic mice. SCD1 is an enzyme that desaturates SFAs, converting them to monounsaturated fatty acids (MUFAs), leading to the formation of neutral lipid droplets. In culture, retrovirus-mediated overexpression of SCD1 or MUFA treatment significantly ameliorated SFA-induced apoptosis in PTECs by enhancing intracellular lipid droplet formation. In contrast, siRNA against SCD1 exacerbated the apoptosis. Both overexpression of SCD1 and MUFA treatment reduced SFA-induced apoptosis via reducing endoplasmic reticulum stress in cultured PTECs. Thus, HFD-induced decrease in renal SCD1 expression may play a pathogenic role in lipotoxicity-induced renal injury, and enhancing SCD1-mediated desaturation of SFA and subsequent formation of neutral lipid droplets may become a promising therapeutic target to reduce SFA-induced lipotoxicity. The present study provides a novel insight into lipotoxicity in the pathogenesis of diabetic nephropathy.

Heparan sulfate containing unsubstituted glucosamine residues: biosynthesis and heparanase-inhibitory activity.

Degradation of heparan sulfate (HS) in the extracellular matrix by heparanase is linked to the processes of tumor invasion and metastasis. Thus, a heparanase inhibitor can be a potential anticancer drug. Because HS with unsubstituted glucosamine residues accumulates in heparanase-expressing breast cancer cells, we assumed that these HS structures are resistant to heparanase and can therefore be utilized as a heparanase inhibitor. As expected, chemically synthetic HS-tetrasaccharides containing unsubstituted glucosamine residues, GlcAß1-4GlcNH3 (+)(6-O-sulfate)α1-4GlcAß1-4GlcNH3 (+)(6-O-sulfate), inhibited heparanase activity and suppressed invasion of breast cancer cells in vitro. Bifunctional NDST-1 (N-deacetylase/N-sulfotransferase-1) catalyzes the modification of N-acetylglucosamine residues within HS chains, and the balance of N-deacetylase and N-sulfotransferase activities of NDST-1 is thought to be a determinant of the generation of unsubstituted glucosamine. We also report here that EXTL3 (exostosin-like 3) controls N-sulfotransferase activity of NDST-1 by forming a complex with NDST-1 and contributes to generation of unsubstituted glucosamine residues.

Altered unfolded protein response is implicated in the age-related exacerbation of proteinuria-induced proximal tubular cell damage.

Aging is a dominant risk factor for end-stage renal disease. We analyzed the mechanism involved in age-related exacerbation of proteinuria-induced proximal tubular cell (PTC) damage by focusing on endoplasmic reticulum-related unfolded protein response (UPR). After equal-degree induction of proteinuria in 24-month-old (aged) and 3-month-old (young) mice by intraperitoneal free fatty acid-bound albumin overload, tubulointerstitial lesions were more severe in aged than in young mice. In aged PTCs, proteinuria-induced cell-adaptive UPR resulting from induction of the molecular chaperone BiP was significantly suppressed, whereas proapoptotic UPR with CHOP overexpression was enhanced. Treatment with the exogenous molecular chaperone tauroursodeoxycholic acid (TUDCA) ameliorated proteinuria-induced tubulointerstitial lesions and PTC apoptosis in aged mice. Among the three UPR branches, alterations in the inositol-requiring 1α (IRE1α) pathway, but not the activating transcription factor 6 or PERK pathway, were associated with impaired BiP induction in aged kidneys. Moreover, siRNA-mediated suppression of BiP and IRE1α exacerbated free fatty acid-bound albumin-induced apoptosis in cultured PTCs, whereas siRNA-mediated CHOP suppression ameliorated apoptosis. Finally, proteinuria-induced BiP induction in PTCs was diminished in kidney specimens from elderly patients. These results indicate that maladaptive UPRs are involved in proteinuria-induced tubulointerstitial lesions exacerbation in aged kidneys, and that supplementation of chaperones may be used to treat elderly patients with persistent proteinuria. These results should improve understanding of cell vulnerability in aged kidneys.

Synthesis of biotinylated keratan sulfate repeating disaccharides.

We synthesized four types of keratan and keratan sulfate repeating disaccharides containing non-sulfate, Galß1-4GlcNAcß, and three types of sulfates, Gal6Sß1-4GlcNAcß, Galß1-4GlcNAc6Sß, and Gal6Sß1-4GlcNAc6Sß in an efficient and stereo-controlled manner. These disaccharides were conjugated with biotin via a hydrophilic linker at the reducing terminal.

[Factors affecting adherence of breast cancer patients to adjuvant hormonal therapy and validation of the evaluation method].

BACKGROUND: The long-term use of hormonal therapy is important for the treatment of patients with breast cancer. Therefore, we evaluated the methods used for measuring adherence and examined factors that influence compliance. Our goal was to improve overall adherence to the treatment. METHODS: Retrospective analyses by using electronic medical records and questionnaires were performed on 294 patients with breast cancer. The patients were classified into 2 groups based on the mean number of days when a dose was missed over a period of 28 days: group A(range, 0-3 days, n=272)and group B (range, B4 days, n=22). Factors that may influence adherence, including age, duration of hormonal therapy, the drug administered in hormonal therapy, the surgical method, axillary lymph node dissection, and adjuvant chemotherapy, were compared between both groups. RESULTS: The adherence rates calculated from electronic medical records and questionnaires were similar. The proportion of patients younger than 50 years was 30% in group A and 50% in group B(p<0.05). Additionally, there was a difference in the duration of hormone therapy(752 days vs 981 days in groups A and B, respectively; p< 0.05). Additional factors that are related to low-risk cancer-related procedures, such as breast conserving surgery, may also be linked to poor adherence. CONCLUSION: Young age and long duration of hormonal therapy are possibly related to poor adherence. Therefore, pharmacists should identify and manage these patients to increase adherence.

Preliminary report on ultrashort perioperative partial-breast irradiation with multicatheter interstitial brachytherapy for early-stage breast cancer.

PURPOSE: Perioperative partial-breast irradiation (PBI) with multicatheter interstitial brachytherapy (MIB) is less invasive and more convenient than postoperative one. This study aimed to compare ultrashort perioperative MIB-PBI (uPBI) and conventional perioperative MIB-PBI (cPBI) performed during the same period of time. METHODS: Inclusion criteria of the study were patients aged ≥ 40 years and those with T0-2 (≤ 3 cm), N0-mi, and negative margins on mammography. The locoregional recurrence (LRR) and toxicity rates were compared between uPBI at a dose of 25.2 Gy in four fractions and cPBI at a dose of 32 Gy in eight fractions. RESULTS: In total, 198 patients (151 with uPBI and 47 with cPBI) were evaluated. At a median follow-up of 20.1 months, one (0.66%) patient in the uPBI group had LRR. The 2-year ipsilateral breast tumor recurrence-free survival rates of the uPBI and cPBI groups were 98.7% and 100%, respectively. The highest toxicity grades were grade 1 in 23 (15.2%) and grade 2 in 2 (1.3%) patients in the uPBI group, and grade 1 in 8 (17.0%) and grade 2 in 1 (2.1%) patient in the cPBI group. None of the patients in the two groups presented with grade 3 and higher toxicities. The toxicity rates between the two groups did not significantly differ. Further, 22 (14.6%) patients in the uPBI group and 8 (17.0%) in the cPBI group, and 3 (2.0%) patients in the uPBI group and 1 (2.1%) in the cPBI had acute and late toxicities, respectively. The timing of toxicity development between the two groups did not significantly differ. CONCLUSIONS: Although this preliminary report included a small sample size and had a short follow-up period, the local control and toxicity rates were similar between the uPBI and cPBI groups. Further research is warranted to investigate the ideal dose schedule of MIB-PBI.

Impact of de-escalating systemic therapy guided by 21-gene assay on locoregional recurrence after partial-breast irradiation.

PURPOSE: Partial-breast irradiation (PBI) has been performed as alternative to whole-breast irradiation (WBI) in breast-conserving therapy (BCT). Recently, the 21-gene recurrence score (RS) was introduced to determine the adjuvant therapy for estrogen receptor (ER)-positive, and human epidermal growth factor receptor 2 (HER2)-negative diseases. However, the impact of RS-based systemic therapy on locoregional recurrence (LRR) following BCT with PBI remains uninvestigated. METHODS AND MATERIALS: Patients with ER-positive, HER2-negative, and node-negative breast cancer who underwent BCT with PBI were examined during May 2012-March 2022. In addition to immunohistochemistry (IHC), RS was available to decide on adjuvant therapy. RESULTS: In total, 431 patients were evaluated with a median followup of 48.6 months. The 4-year LRR-free survival rates were 97.3% and 96.4% in the IHC and RS cohorts, respectively (p = 0.50). Ki67 of >20% was significantly associated with LRR in the multivariate analysis (HR 4.39, p < 0.05). For patients with Ki67 > 20%, 29 of 71 (40.8%) and 46 of 59 (78.0%) patients received only endocrine therapy in the IHC and RS cohorts, respectively (p < 0.0001). For patients with Ki67 >20% who received only endocrine therapy, the 4-year LRR-free survival rates were 91.8% in the IHC cohort and 94.6% in the RS cohort (p = 0.29) CONCLUSIONS: Although the introduction of RS increased the number of patients receiving endocrine therapy alone for Ki67 >20% of disease by two times, the LRR-free survival after BCT with PBI could be maintained. However, further studies from multiple institutions with longer followup data are required.

Synthesis and interaction with midkine of biotinylated chondroitin sulfate tetrasaccharides.

Regiospecifically sulfated chondroitin sulfate repeating tetrasaccharides, CS-OO, GlcAß-GalNAcß-GlcAß-GalNAcß;CS-EE, GlcAß-GalNAc(4S6S)ß-GlcAß-GalNAc(4S6S)ß; and CS-AA, GlcAß-GalNAc(4S)ß-GlcAß-GalNAc(4S)ß, having biotin linked with a hydrophilic linker at the reducing terminal were synthesized effectively by a coupling of the corresponding disaccharide units and regioselective sulfation. CS-EE showed greater affinity for midkine than CS-AA and CS-OO.

Inhibition of mitochondrial fission protects podocytes from albumin-induced cell damage in diabetic kidney disease.

AIMS: Identifying the mechanisms that underlie progression from endothelial damage to podocyte damage, which leads to massive proteinuria, is an urgent issue that must be clarified to improve renal outcome in diabetic kidney disease (DKD). We aimed to examine the role of dynamin-related protein 1 (Drp1)-mediated regulation of mitochondrial fission in podocytes in the pathogenesis of massive proteinuria in DKD. METHODS: Diabetes- or albuminuria-associated changes in mitochondrial morphology in podocytes were examined by electron microscopy. The effects of albumin and other diabetes-related stimuli, including high glucose (HG), on mitochondrial morphology were examined in cultured podocytes. The role of Drp1 in podocyte damage was examined using diabetic podocyte-specific Drp1-deficient mice treated with neuraminidase, which removes endothelial glycocalyx. RESULTS: Neuraminidase-induced removal of glomerular endothelial glycocalyx in nondiabetic mice led to microalbuminuria without podocyte damage, accompanied by reduced Drp1 expression and mitochondrial elongation in podocytes. In contrast, streptozotocin-induced diabetes significantly exacerbated neuraminidase-induced podocyte damage and albuminuria, and was accompanied by increased Drp1 expression and enhanced mitochondrial fission in podocytes. Cell culture experiments showed that albumin stimulation decreased Drp1 expression and elongated mitochondria, although HG inhibited albumin-associated changes in mitochondrial dynamics, resulting in apoptosis. Podocyte-specific Drp1-deficiency in mice prevented diabetes-related exacerbation of podocyte damage and neuraminidase-induced development of albuminuria. Endothelial dysfunction-induced albumin exposure is cytotoxic to podocytes. Inhibition of mitochondrial fission in podocytes is a cytoprotective mechanism against albumin stimulation, which is impaired under diabetic condition. Inhibition of mitochondrial fission in podocytes may represent a new therapeutic strategy for massive proteinuria in DKD.

Improvement in Decline Rate of Estimated Glomerular Filtration Rate after Febuxostat Treatment in a Fabry Disease Patient with Enzyme Replacement Therapy-resistant Proteinuria.

Fabry disease is an inherited lysosomal disorder caused by mutations in the alpha-galactosidase A gene. We herein report a Fabry disease patient with enzyme replacement therapy (ERT)-resistant proteinuria who showed improvement in the estimated glomerular filtration rate (eGFR) decline rate after uric acid (UA)-lowering therapy. The patient was diagnosed with Fabry disease at 36 years old. After that, even under ERT, proteinuria and eGFR decline persisted. During the clinical course, serum UA levels were elevated with increases in renal tubular damage markers. Febuxostat administration immediately improved tubular damage and prevented further eGFR decline. UA-mediated tubulopathy may become an additional therapeutic target for eGFR decline in Fabry disease.

Computed tomography-guided partial-breast brachytherapy using implanted catheters as fiducial markers versus co-registered magnetic resonance imaging.

PURPOSE: Partial-breast irradiation (PBI) needs accurate cavity delineation with computed tomography (CT). In perioperative PBI using multicatheter-interstitial brachytherapy (MIB), catheters implanted during surgery were enabled as fiducial markers. Magnetic resonance imaging (MRI) can also assist delineation with CT. METHODS: Patients receiving MIB-PBI were analyzed. Cavity visualization scores (CVSs) were categorized with CT. With catheter-based delineation (CBD), the relationship between cavity boundaries and catheters were used to contour the tumor bed. Co-registered MRI delineation (CMD) was also performed. The correlation between cavity volume and the excised tissue weight was compared for the two techniques. RESULTS: The association between CVS and preoperative characteristics in 159 patients showed mammographic breast density (MBD) remained correlated to CVS on multiple regression analyses; CVS = 5.2-0.61 x MBD (p < 0.0001). In 43 patients, the cavity volumes determined with CBD vs CMD were 12.8 ±â€¯6.4 cm3 vs 16.1 ±â€¯12.4 cm3 (p < 0.0001), and their plots with excised weights showed the best fitting lines were 0.29 vs 0.48 (p < 0.0001), respectively. The correlation coefficients for CBD vs CMD were 0.65 vs 0.55 (p = 0.20) in low (CVS 1-3, n = 27) and 0.72 vs 0.58 (p = 0.36) in high visualized cavities (CVS 4-5, n = 16), respectively. CONCLUSIONS: The use of implanted catheters as fiducial markers was associated with smaller cavities and greater correlations with the excised tissue weights than co-registration with MRI. This might be a useful technique, especially for patients with dense breasts on mammography.

Predicting adherence of dose-volume constraints for personalized partial-breast irradiation technique.

PURPOSE: Multicatheter interstitial brachytherapy (MIB) and external-beam (EB) radiotherapy are established partial-breast irradiation (PBI) techniques. Although EB-PBI is widely available, it requires extra irradiated margins for target uncertainties. We examined the impact of EB-PBI on dose-volume constraints as compared to MIB-PBI. METHODS AND MATERIALS: Among 653 patients receiving MIB-PBI between October 2008 and April 2020, consequent 159 patients after September 2018 were examined. Clinical target volume (CTV) included the lumpectomy cavity plus 1.0 cm. Planning target volume (PTV) for EB-PBI was defined as CTV with 1.0-cm expansion. Because the ratio of PTV to breast volume (RPB) was related to cosmesis, <25% of RPB was defined as suitable for the ipsilateral breast constraints. Preoperative breast size was classified as very small (<350 cm3), small (350-699 cm3), and medium or large (≥700 cm3). According to each category, the dose-volume constraints of the organs at risk were compared between the two PBI techniques. RESULTS: Patients including 84 very small, 59 small, and 16 moderate to large breasts were examined. Although RPB was suitable in all patients receiving MIB-PBI, it was achieved in 74 patients (46.5%) receiving EB-PBI (p < 0.0001). The suitable RPB in patients with very small, small, and moderate to large breast was 32.1%, 55.9%, and 100%, respectively (p < 0.0001). Normal-tissue constraints for the other organs could be satisfied in patients with moderate to large breasts. CONCLUSION: Although EB-PBI may be an appropriate option for patients with moderate to large breasts, MIB-PBI could still be a crucial technique, especially for patients with small breasts.

Oleate and eicosapentaenoic acid attenuate palmitate-induced inflammation and apoptosis in renal proximal tubular cell.

Free fatty acid (FFA)-bound albumin, which is filtrated through the glomeruli and reabsorbed into proximal tubular cells, is one of the crucial mediators of tubular damage in proteinuric kidney disease. In this study, we examined the role of each kind of FFA on renal tubular damage in vitro and tried to identify its molecular mechanism. In cultured proximal tubular cells, a saturated fatty acid, palmiate, increased the expression of monocyte chemoattractant protein-1 (MCP-1), but this effect was abrogated by co-incubation of monounsaturated fatty acid, oleate, or ω-3 polyunsaturated fatty acid, eicosapentaenoic acid (EPA). Palmitate led to intracellular accumulation of diacylglycerol (DAG) and subsequent activation of protein kinase C protein family. Among the several PKC inhibitors, rottlerin, a PKCθ inhibitor, prevented palmitate-induced MCP-1 expression via inactivation of NFB pathway. Overexpression of dominant-negative PKCθ also inhibited palmitate-induced activation of MCP-1 promoter. Furthermore, palmitate enhanced PKCθ-dependent mitochondrial apoptosis, which was also prevented by co-incubation with oleate or EPA through restoration of pro-survival Akt pathway. Moreover, oleate and EPA inhibited palmitate-induced PKCθ activation through the conversion of intracellular DAG to triglyceride with the restoration of diacylglycerol acyltransferase 2 expression. These results suggest that oleate and EPA have protective effects against the palmitate-induced renal tubular cell damage by inhibiting PKCθ activation.

Efficacy of Single-Plane Implant Technique in Partial Breast Brachytherapy in Small-Breasted Patients.

PURPOSE: Partial-breast irradiation (PBI) using multicatheter-interstitial brachytherapy (MIB) has been supported by some randomized trials to date. However, it remains underused in Asian countries because of the population's typically smaller breasts. Single-plane implantation has been recommended in these individuals, but limited data on the clinical efficacy exist. We performed a retrospective chart review to compare the tumor control and long-term cosmesis in patients treated with the single-plane implant technique. METHODS AND MATERIALS: Patients receiving MIB-PBI between October 2008 and December 2018 were evaluated. PBI was initiated on the same day of the surgery via an intraoperative catheter implant, delivering 32 Gy by 8 fractions. Tumor control based on the rate of freedom from ipsilateral tumor recurrence (IBTR), disease-free survival, and long-term cosmesis using the Harvard scale was evaluated to compare between the single- and double-/triple-plane implant techniques. RESULTS: Five hundred sixteen patients with 526 lesions received MIB-PBI with a median follow-up of 53.1 months. Patients treated by single- and double- or triple-plane implant numbered 288 (54.8%) and 238 (45.2%), respectively. The 4-year probabilities of IBTR-free survival and disease-free survival were 97.5% and 96.5% in single-plane implant and 98.6% (P = .42) and 98.0% (P = .18) in double- or triple-plane implant MIB-PBI, respectively. Although young age (P < .05) and positive surgical margins (P < .01) were selected as independent risk factors for IBTR, single-plane implantation was not recognized as a risk factor of IBTR. Sixty-one of 69 single-plane implant patients (88.4%) and 84 of 92 double-/triple-plane implant patients (91.3%) reported excellent to good cosmetic results (P = .73). CONCLUSIONS: Although this was a retrospective study from a single institution and cosmesis was evaluated using a subjective method, this is the first report to validate single-plane implant MIB-PBI for use in small-breasted patients. Further multicenter research is required.