An epidermal growth factor receptor-targeting immunotoxin based on IgG shows potent antitumor activity against head and neck cancer.

The epidermal growth factor receptor (EGFR) is an important target for cancer therapies. Many head and neck cancer (HNC) cells have been reported to overexpress EGFR; therefore, anti-EGFR therapies have been attempted in patients with HNC. However, its clinical efficacy is limited owing to the development of drug resistance. In this study, we developed an EGFR-targeting immunotoxin consisting of a clinically proven anti-EGFR IgG (cetuximab; CTX) and a toxin fragment (LR-LO10) derived from Pseudomonas exotoxin A (PE) using a novel site-specific conjugation technology (peptide-directed photo-crosslinking reaction), as an alternative option. The immunotoxin (CTX-LR-LO10) showed specific binding to EGFR and properties of a typical IgG, such as stability, interactions with receptors of immune cells, and pharmacokinetics, and inhibited protein synthesis via modification of elongation factor-2. Treatment of EGFR-positive HNC cells with the immunotoxin resulted in apoptotic cell death and the inhibition of cell migration and invasion. The efficacy of CTX-LR-LO10 was evaluated in xenograft mouse models, and the immunotoxin exhibited much stronger tumor suppression than CTX or LR-LO10. Transcriptome analyses revealed that the immunotoxins elicited immune responses and altered the expression of genes related to its mechanisms of action. These results support the notion that CTX-LR-LO10 may serve as a new therapeutic agent targeting EGFR-positive cancers.

Ibulocydine Inhibits Migration and Invasion of TNBC Cells via MMP-9 Regulation.

Triple-negative breast cancer (TNBC) accounts for approximately 15-20% of all breast cancer types, indicating a poor survival prognosis with a more aggressive biology of metastasis to the lung and a short response duration to available therapies. Ibulocydine (IB) is a novel (cyclin-dependent kinase) CDK7/9 inhibitor prodrug displaying potent anti-cancer effects against various cancer cell types. We performed in vitro and in vivo experiments to determine whether IB inhibits metastasis and eventually overcomes the poor drug response in TNBC. The result showed that IB inhibited the growth of TNBC cells by inducing caspase-mediated apoptosis and blocking metastasis by reducing MMP-9 expression in vitro. Concurrently, in vivo experiments using the metastasis model showed that IB inhibited metastasis of MDA-MB-231-Luc cells to the lung. Collectively, these results demonstrate that IB inhibited the growth of TNBC cells and blocked metastasis by regulating MMP-9 expression, suggesting a novel therapeutic agent for metastatic TNBC.

Factors Causing Unintended Sagittal and Axial Alignment Changes in High Tibial Osteotomy: Comparative 3-Dimensional Analysis of Simulation and Actual Surgery.

BACKGROUND: Unintended secondary changes in the posterior tibial slope (PTS) and tibial torsion angle (TTA) may occur after medial open-wedge high tibial osteotomy (MOWHTO). In surgical procedures using patient-specific instruments (PSIs), it is essential to reproduce the PTS and TTA that were planned in simulations. PURPOSE: To analyze the factors causing unintended sagittal and axial alignment changes after MOWHTO. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Overall, 63 patients (70 knees) who underwent MOWHTO using a PSI between June 2020 and June 2023 were retrospectively reviewed. Preoperative and postoperative computed tomography scans were 3-dimensionally reconstructed. Simulated osteotomy was performed so that the weightbearing line could pass through the target point. A PSI gapper was 3-dimensionally printed to fit the posteromedial corner of the osteotomy gap in the simulated HTO model. After MOWHTO using the PSI gapper, the actual postoperative model was compared with the preoperative or simulation model. This assessment included PTS, TTA, hinge axis, and osteotomy-related parameters. Cortical breakage around the lateral hinge was evaluated to assess stability. RESULTS: The mean PTS and TTA did not change in the simulation. However, significant changes were observed in the actual postoperative PTS and TTA (change, -2.4°± 2.2° and -3.9°± 4.7°, respectively). The PTS was reduced, while the TTA decreased with internal rotation of the distal fragment. The difference in the axial hinge axis angle (AHA) between the simulation and actual surgery was the factor most correlated with the difference in the PTS (r = 0.625; P < .001). In regression analysis, the difference in the AHA was the only factor associated with the difference in the PTS (ß = 0.558; P = .001), and there were no factors that showed any significant associations with the difference in the TTA. In subgroup analyses for the change in the TTA, the correction angle and anterior osteotomy angle were significantly higher in the more internal rotation group (P = .023 and P = .010, respectively). The TTA change was significantly higher in the unstable group with lateral cortical breakage (P = .018). The unstable group was more likely to show an internal rotation of ≥5° (odds ratio, 5.0; P = .007). CONCLUSION: The AHA was associated with a difference in the PTS between the simulation and actual surgery. The change in the TTA was caused by a combination of multiple factors, such as a large correction angle and anterior osteotomy angle, but mainly by instability of the lateral cortical hinge.

Implantation of hUCB-MSCs generates greater hyaline-type cartilage than microdrilling combined with high tibial osteotomy.

PURPOSE: To compare the outcomes of treating large cartilage defects in knee osteoarthritis using human allogeneic umbilical cord blood-derived mesenchymal stem cell (hUCB-MSC) implantation or arthroscopic microdrilling as a supplementary cartilage regenerative procedure combined with high tibial osteotomy (HTO). METHODS: This 1-year prospective comparative study included 25 patients with large, near full-thickness cartilage defects (International Cartilage Repair Society grade ≥ IIIB) in the medial femoral condyles and varus malalignment. Defects were treated with hUCB-MSC implantation or arthroscopic microdrilling combined with HTO. The primary outcomes were pain visual analogue scale and International Knee Documentation Committee subjective scores at 12, 24 and 48 weeks. Secondary outcomes included arthroscopic, histological and magnetic resonance imaging assessments at 1 year. RESULTS: Fifteen and 10 patients were treated via hUCB-MSC implantation and microdrilling, respectively. Baseline demographics, limb alignment and clinical outcomes did not significantly differ between the groups. Cartilage defects and total restored areas were significantly larger in the hUCB-MSC group (7.2 ± 1.9 vs. 5.2 ± 2.1 cm2, p = 0.023; 4.5 ± 1.4 vs. 3.0 ± 1.6 cm2, p = 0.035). The proportion of moderate-to-strong positive type II collagen staining was significantly higher in the hUCB-MSC group compared to that in the microdrilled group (93.3% vs. 60%, respectively). Rigidity upon probing resembled that of normal cartilage tissue more in the hUCB-MSC group (86.7% vs. 50.0%, p = 0.075). Histological findings revealed a higher proportion of hyaline cartilage in the group with implanted hUCB-MSC (p = 0.041). CONCLUSION: hUCB-MSC implantation showed comparable clinical outcomes to those of microdrilling as supplementary cartilage procedures combined with HTO in the short term, despite the significantly larger cartilage defect in the hUCB-MSC group. The repaired cartilage after hUCB-MSC implantation showed greater hyaline-type cartilage with rigidity than that after microdrilling. LEVEL OF EVIDENCE: Level II, Prospective Comparative Cohort Study.

Tumor-like lymphoplasmacytic conjunctivitis in the third eyelid in a dog.

This report aims to describe a case of tumor-like lymphoplasmacytic conjunctivitis in a 7-year-old spayed-female Pomeranian. On complete ophthalmic examination, a mass with papillary projections was noted on the bulbar surface of the right third eyelid. Debulking of the mass was performed while preserving as much of the third eyelid as possible. On the histopathological examination, the mass was diagnosed as lymphoplasmacytic conjunctivitis with mild epithelial hyperplasia. Although a slight regrowth of the mass was noted 3 weeks after surgery, intralesional injection of triamcinolone acetonide led to its disappearance. There was no further recurrence after 5 months.

Allogeneic umbilical cord blood-derived mesenchymal stem cell implantation versus microdrilling combined with high tibial osteotomy for cartilage regeneration.

This study compared cartilage regeneration outcomes in knee osteoarthritis (OA) using allogeneic human umbilical cord blood-derived mesenchymal stem cell (hUCB-MSC) implantation and microdrilling with high tibial osteotomy (HTO). Fifty-four patients (60 knees) were included: 24 (27 knees) in the hUCB-MSC group and 30 (33 knees) in the microdrilling group. Both groups showed significant improvements in pain and functional scores at 6, 12, and 24 months compared to baseline. At 24 months, the hUCB-MSC group had significantly improved scores. Arthroscopic assessment at 12 months revealed better cartilage healing in the hUCB-MSC group. In subgroup analysis according to the defect site, hUCB-MSC implantation showed superior cartilage healing for anterior lesions. In conclusion, both treatments demonstrated effectiveness for medial OA. However, hUCB-MSC implantation had better patient-reported outcomes and cartilage regeneration than microdrilling. The study suggests promising approaches for cartilage restoration in large knee defects due to OA.

Prognostic Factors for Clinical Outcome and Cartilage Regeneration after Implantation of Allogeneic Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells in Large-Sized Cartilage Defects with Osteoarthritis.

OBJECTIVE: To analyze the prognostic factors for clinical outcomes and cartilage regeneration after the implantation of allogeneic human umbilical cord blood mesenchymal stem cell (hUCB-MSC) for treating large-sized cartilage defects with osteoarthritis. DESIGN: This study is a case-series with multiple subgroup analyses that divides the included patients into multiple subgroups based on various factors. Overall, 47 patients who underwent hUCB-MSC implantation were included. The patient-reported outcomes, magnetic resonance imaging (MRI), and second-look arthroscopy were used to assess the outcomes. RESULTS: Combined realignment surgery significantly correlated with clinical outcomes, particularly pain. No other factors significantly influenced the clinical outcomes in short-term period. Subgroups with large defect sizes or meniscal insufficiency showed significantly poor MRI and arthroscopy outcomes (MRI, P = 0.001, P = 0.001; arthroscopy, P = 0.032, P = 0.042). The logistic regression showed that patients with a 1 cm2 larger defect size were 1.91 times less likely to achieve favorable MRI outcomes (P = 0.017; odds ratio [OR], 1.91). Cut-off value to predict the poor outcome was >5.7 cm2 (area under the curve, 0.756). A cartilage defect size >5.7 cm2 was the major poor prognostic factor for cartilage regeneration on MRI (P = 0.010; OR, 17.46). If the postoperative alignment shifted by 1° opposite to the cartilage defect, it was 1.4 times more likely to achieve favorable MRI outcomes (P = 0.028; OR, 1.4). CONCLUSION: Combining realignment surgery showed a better prognosis for pain improvement. Cartilage defect size, meniscal function, and postoperative alignment are significant prognostic factors for cartilage regeneration. A cartilage defect size >5.7 cm2 was significantly related to poor cartilage regeneration.

Preoperative joint line obliquity, a newly identified factor for overcorrection, can be incorporated into a novel preoperative planning method to optimise alignment in high tibial osteotomy.

PURPOSE: The aim of this study was to analyse the factors associated with additional postoperative alignment changes after accurate bony correction by selecting only patients with well-performed bony correction as planned and develop a method of incorporating significant factors into preoperative planning. METHODS: Among 104 consecutive patients who underwent medial open wedge high tibial osteotomy (MOWHTO) between October 2019 and July 2022, 61 with well-performed bony corrections were retrospectively reviewed. The major criterion for well-performed bony correction was a difference of <1° between the simulated medial proximal tibial angle (MPTA) and the actual postoperative MPTA as measured in three dimensions. Radiographic parameters, such as the joint line convergence angle (JLCA) and joint line obliquity (JLO), were measured preoperatively and postoperatively, utilising standing and supine whole lower extremity anteroposterior, valgus and varus stress radiographs. Multiple linear regression analysis identified the factors affecting alignment changes, and a prediction model was developed. A method for applying this prediction model to preoperative planning was proposed. RESULTS: Preoperative JLCA on standing (preJLCAstd ), preoperative JLCA on 0° valgus stress radiograph (vgJLCA0 ), and preoperative JLO (preJLO) were significantly correlated with JLCA change (∆JLCA) (p < 0.001, p < 0.001, p = 0.006). The prediction model was estimated as ∆JLCA = 0.493 × (vgJLCA0 ) - 0.727 × (preJLCAstd ) + 0.189 × (preJLO) - 1.587 in. (R = 0.815, modified R2 = 0.646, p < 0.001). The proposed method resulted in a reduced overcorrection rate (p = 0.003) and an improved proportion of acceptable alignments (p = 0.013). CONCLUSION: PreJLCAstd , vgJLCA0  and preJLO can be used to estimate ∆JLCA. PreJLO was recently identified as a significant factor associated with additional alignment changes. Utilising the proposed preoperative planning and a prediction model with these factors shows promise in calibrating postoperative alignment after MOWHTO. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Short-term Impact of Hormone Replacement Therapy on Risk of Breast Cancer in BRCA Mutation Carriers: A Nationwide Study in South Korea.

PURPOSE: BRCA1/2 mutations are well-known risk factors for breast and ovarian cancers in women. Risk-reducing salpingo-oophorectomy (RRSO) is the standard treatment for preventing ovarian cancer with BRCA mutations. Postmenopausal syndrome (symptoms after RRSO can be alleviated by hormone replacement therapy (HRT); however, the use of HRT in carriers of BRCA mutations has been controversial because of the concern that HRT increases the risk of breast cancer. This study aimed to evaluate the effects of HRT in BRCA mutation carriers who underwent RRSO. MATERIALS AND METHODS: A total of 151 carriers, who underwent RRSO between 2013 and 2020 after the diagnosis of BRCA1 or BRCA2 mutations were selected and followed up for a median of 3.03 years. Patients were divided into two groups: those who received HRT after RRSO (n=33) and those who did not (n=118). We compared the incidence of breast cancer over time between these two groups. RESULTS: There was no significant difference in the incidence of breast cancer between women who received HRT and those who did not (p=0.229). Multivariate logistic regression analysis, adjusted for age and parity revealed no significant difference in the risk of breast cancer between these two groups (hazard ratio, 0.312; 95% confidence interval, 0.039 to 2.480; p=0.278). CONCLUSION: In this study, we found no relationship between post-RRSO HRT and breast cancer in the population with BRCA mutations. Therefore, healthcare providers may consider the alleviation of symptoms of postmenopausal syndrome through HRT in patients who underwent RRSO.

AXL is required for hypoxia-mediated hypoxia-inducible factor-1 alpha function in glioblastoma.

Glioblastoma (GBM) is the most aggressive type of central nervous system tumor. Molecular targeting may be important when developing efficient GBM treatment strategies. Sequencing of GBMs revealed that the receptor tyrosine kinase (RTK)/RAS/phosphatidylinositol-3-kinase pathway was altered in 88% of samples. Interestingly, AXL, a member of RTK, was proposed as a promising target in glioma therapy. However, the molecular mechanism of AXL modulation of GBM genesis and proliferation is still unclear. In this study, we investigated the expression and localization of hypoxia-inducible factor-1 alpha (HIF-1α) by AXL in GBM. Both AXL mRNA and protein are overexpressed in GBM. Short-interfering RNA knockdown of AXL in U251-MG cells reduced viability and migration. However, serum withdrawal reduced AXL expression, abolishing the effect on viability. AXL is also involved in hypoxia regulation. In hypoxic conditions, the reduction of AXL decreased the level and nuclear localization of HIF-1α. The co-expression of HIF-1α and AXL was found in human GBM samples but not normal tissue. This finding suggests a mechanism for GBM proliferation and indicates that targeting AXL may be a potential GBM therapeutic. Supplementary Information: The online version contains supplementary material available at 10.1007/s43188-023-00195-z.

Prevalence of feline ophthalmic disorders in South Korea: a retrospective study (2009-2021).

OBJECTIVES: This study aimed to determine the prevalence and clinical presentation of ocular diseases in cats in South Korea. METHODS: Medical records of cats that were presented for ophthalmology services at Seoul National University Veterinary Medical Teaching Hospital between 2009 and 2021 were reviewed. Collected data included patient signalment, clinical signs, diagnosed ophthalmic disorders and affected eyes. Odds ratios were calculated when a variable was over-represented. RESULTS: This study recorded a total of 358 eyes (180 cats). Domestic shorthair (DSH) was the most common breed (42.2%), followed by Persian (13.9%) and Scottish Fold (8.3%); 14 (35.6%) other breeds were recorded. The median age at the first presentation was 3 years (range 2 months to 17 years); the highest percentage of cats presented at <1 year (21.7%). The most affected ocular structure was the cornea (28.5%), followed by the lens (19.9%) and uvea (15.3%). The most frequently reported disorders were corneal ulceration (13.2%), uveitis (11.9%), incipient cataract (11.0%), keratitis (5.4%), secondary glaucoma (5.2%) and sequestrum (4.2%). The Exotic Shorthair breed was significantly over-represented with regard to entropion and periorbital fat prolapse (P <0.01). The DSH breed was significantly over-represented with regard to eyelid agenesis (P <0.01). CONCLUSIONS AND RELEVANCE: This study provides prevalence information for feline ophthalmic diseases and could contribute important data for diagnosing, treating and preventing feline ophthalmic diseases in South Korea.

Ezetimibe increases resistance to oxidative stress and extends lifespan mimicking dietary restriction in Caenorhabditis elegans

Ezetimibe is an approved drug for lowering plasma LDL (low-density lipoprotein) level via inhibition of cholesterol absorption. Derivatives of ezetimibe reduce inflammatory response and oxidative stress. In the present study, we investigated the effect of dietary supplementation with ezetimibe in response to environmental stressors and found that ezetimibe increases resistance to oxidative stress and ultraviolet irradiation. Ezetimibe also significantly extended lifespan accompanying reduced fertility, which is a common trade-off for longevity in C. elegans. Cellular level of reactive oxygen species was increased and the expression of stress-responsive genes, hsp-16.2 and sod-3, was induced by dietary supplementation with ezetimibe, suggesting a hormetic effect on oxidative stress response and lifespan. Ezetimibe also significantly prevented amyloid beta-induced toxicity and completely reversed increased mortality by high-glucose diet. Nuclear localization of DAF-16 required for the prevention of amyloid beta-induced toxicity was enhanced by ezetimibe supplementation. Lifespan assay using known long-lived mutants, age-1, clk-1, and eat-2, revealed that lifespan extension by ezetimibe specifically overlapped with that of eat-2 mutants, which are genetic models of dietary restriction. Effect of ezetimibe on lifespan of worms fed with diluted bacteria suggested that ezetimibe mimics the effect of dietary restriction on lifespan. These findings suggest that ezetimibe exhibits anti-oxidative and anti-aging effects through hormesis and works as a dietary-restriction mimetic on lifespan extension.

Phenotyping COPD Patients with Emphysema Distribution Using Quantitative CT Measurement; More Severe Airway Involvement in Lower Dominant Emphysema.

Purpose: We explored the differences in clinical manifestations of COPD patients regarding emphysema distribution along with evidence of airway involvement in chest computed tomography (CT) scans. Patients and Methods: The patients were divided into three groups according to the emphysema distribution: the upper dominant (UD), lower dominant (LD), and homogeneous (HD) groups. Airway wall thickness was quantitatively measured and the presence of bronchiectasis and/or bronchial wall thickening (BE/BWT) was visually assessed. Baseline characteristics including the evidence of airway involvement and long-term outcomes were compared among the three groups. Non-severe patients of each group were first treated with 3 months of ICS/LABA combination after 2 weeks of wash-out period and lung functions before and after the treatment were compared. Results: Of the 425 patients, 141 were in the UD, 107 in LD, and 177 in HD. The LD had more severe airway obstruction with lower emphysema index (EI) than the UD (LD vs UD; FEV1, 49.5-14.9 vs 54.6-16.5; EI, 21.0 [IQR: 14.0-33.1] vs 26.3 [IQR: 15.8-39.0]). The LD showed thicker airways (higher WA% and Pi10) and more severe air trapping (higher RV and RV/TLC) than UD. A larger proportion of patients in LD had BE/BWT (35.5% in LD vs 11.3% in UD). In LD, more patients experienced acute exacerbations and the time to first exacerbation was shorter than UD. Non-severe patients in LD treated with 3 months of ICS/LABA combined inhalers showed a notable reduction of RV than UD (LD vs UD; -531.1-936.5 vs -86.5-623.5). Conclusion: The LD showed a more prominent airway involvement than UD, which may cause more frequent exacerbations and a marked reduction of RV after the ICS/LABA combination treatment in LD. Phenotyping of the COPD patients using quantitatively measured emphysema distribution would be useful for predicting treatment response and exacerbation.

The potential inhibitory effect of ginsenoside Rh2 on mitophagy in UV-irradiated human dermal fibroblasts.

Background: In addition to its use as a health food, ginseng is used in cosmetics and shampoo because of its extensive health benefits. The ginsenoside, Rh2, is a component of ginseng that inhibits tumor cell proliferation and differentiation, promotes insulin secretion, improves insulin sensitivity, and shows antioxidant effects. Methods: The effects of Rh2 on cell survival, extracellular matrix (ECM) protein expression, and cell differentiation were examined. The antioxidant effects of Rh2 in UV-irradiated normal human dermal fibroblast (NHDF) cells were also examined. The effects of Rh2 on mitochondrial function, morphology, and mitophagy were investigated in UV-irradiated NHDF cells. Results: Rh2 treatment promoted the proliferation of NHDF cells. Additionally, Rh2 increased the expression levels of ECM proteins and growth-associated immediate-early genes in ultraviolet (UV)-irradiated NHDF cells. Rh2 also affected antioxidant protein expression and increased total antioxidant capacity. Furthermore, treatment with Rh2 ameliorated the changes in mitochondrial morphology, induced the recovery of mitochondrial function, and inhibited the initiation of mitophagy in UV-irradiated NHDF cells. Conclusion: Rh2 inhibits mitophagy and reinstates mitochondrial ATP production and membrane potential in NHDF cells damaged by UV exposure, leading to the recovery of ECM, cell proliferation, and antioxidant capacity.

Functional characteristics and research trends of PDE11A in human diseases (Review).

cAMP and cGMP are important secondary messengers involved in cell regulation and metabolism driven by the G protein­coupled receptor. cAMP is converted via adenylyl cyclase (AC) and activates protein kinase A to phosphorylate intracellular proteins that mediate specific responses. cAMP signaling serves a role at multiple steps in tumorigenesis. The level of cAMP is increased in association with cancer cell formation through activation of AC­stimulatory G protein by mutation. Phosphodiesterases (PDEs) hydrolyze cAMP and cGMP to AMP and GMP. PDEs are composed of 11 families, and each can hydrolyze cAMP and cGMP or both cAMP and cGMP. PDEs perform various roles depending on their location and expression site, and are involved in several diseases, including male erectile dysfunction, pulmonary hypertension, Alzheimer's disease and schizophrenia. PDE11A is the 11th member of the PDE family and is characterized by four splice variants with varying tissue expression and N­terminal regulatory regions. Among tissues, the expression of PDE11A was highest in the prostate, and it was also expressed in hepatic skeletal muscle, pituitary, pancreas and kidney. PDE11A is the first PDE associated with an adrenocortical tumor associated genetic condition. In several studies, three PDE11A mutations have been reported in patients with Cushing syndrome with primary pigmented nodular adrenocortical disease or isolated micronodular adrenocortical disease without other genetic defects. It has been reported that an increase in PDE11A expression affects the proliferation of glioblastoma and worsens patient prognosis. The present mini­review summarizes the location of PDE11A expression, the impact of structural differences and disease relevance.

Autophagy: Guardian of Skin Barrier.

Autophagy is a major degradation pathway that removes harmful intracellular substances to maintain homeostasis. Various stressors, such as starvation and oxidative stress, upregulate autophagy, and the dysregulation of autophagy is associated with various human diseases, including cancer and skin diseases. The skin is the first defense barrier against external environmental hazards such as invading pathogens, ultraviolet rays, chemical toxins, and heat. Although the skin is exposed to various stressors that can activate autophagy, the roles of autophagy in the skin have not yet been fully elucidated. Accumulating evidence suggests that autophagy is closely associated with pathogenesis and the treatment of immune-related skin diseases. In this study, we review how autophagy interacts with skin cells, including keratinocytes and immune cells, enabling them to successfully perform their protective functions by eliminating pathogens and maintaining skin homeostasis. Furthermore, we discuss the implications of autophagy in immune-related skin diseases, such as alopecia areata, psoriasis, and atopic dermatitis, and suggest that a combination of autophagy modulators with conventional therapies may be a better strategy for the treatment of these diseases.

Phosphodiesterase 11 A (PDE11A), a potential biomarker for glioblastoma.

Phosphodiesterase 11A (PDE11A), a 3',5'-cyclic nucleotide phosphodiesterase, is a key regulator of intracellular signaling that functions by degrading cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). However, the function of PDE11A in brain tumors is currently unclear. In this study, we found that PDE11A may be involved in glioblastoma development. The protein and mRNA levels of PDE11A were significantly higher in U87-MG, U251-MG and U343-MG glioblastoma cell lines. Gene expression analyses by deep-sequencing revealed that PDE11A mRNA levels were higher in U87-MG and U251-MG cells compared to other cells in the cerebral cortex. A comprehensive analysis of The Cancer Genome Atlas (TCGA) data revealed that PDE11A expression was also elevated in glioblastoma patients. Taken together, these data indicate that PDE11A expression was increased in glioblastoma cell lines and glioma patients, suggesting that PDE11A could be a putative diagnostic marker and therapeutic target for glioma.

Antibody-immunotoxin Conjugate Using FcBP-mediated Photoconjugation to Treat Cancer.

BACKGROUND/AIM: Cytotoxic payload conjugation to antibodies efficiently suppresses tumors and contributes to the improvement of cancer survival. In our previous study, c-Kit targeting antibody-drug conjugate (2G4-DM1) with DM1, a microtubule inhibitor, efficiently suppressed tumor growth. However, slow-growing c-Kit-positive tumors, such as GIST-48, did not efficiently respond to DM1. In this study, we aimed to treat tumors using 2G4 immunotoxin with Pseudomonas exotoxin A (PE) as a payload. MATERIALS AND METHODS: Modified FcBP-PE24 containing p-benzoyl-L-phenylalanine, unnatural amino acid, was expressed in E. coli and purified. Then, photoconjugation of 2G4 antibody and FcBP-PE24 at 365 nm was carried out and 2G4 immunotoxin was purified using anion exchange chromatography. In vitro cytotoxicity of 2G4 immunotoxins was assessed in HMC-1.2, GIST-48, and MDA-MB-453 cells. Then, in vivo efficacy analysis was performed using C.B-17 SCID mice. RESULTS: 2G4 immunotoxin efficiently induced cytotoxicity in 2G4-DM1-resistant HMC-1.2 and GIST-48 cells by inhibiting protein synthesis but not in c-Kit-negative MDA-MB-453 cells. The results showed ~200-fold or more increase in cytotoxicity against c-Kit-positive cells compared to IC50 of 2G4-DM1. In addition, 2G4 immunotoxin suppressed tumor growth in the in vivo xenograft mouse model. CONCLUSION: 2G4 immunotoxins could be an alternative therapeutic strategy for microtubule inhibitor- resistant cancer cells.

Emerging role of LETM1/GRP78 axis in lung cancer.

The selective autophagy of damaged mitochondria is called mitophagy. Mitochondrial dysfunction, mitophagy, and apoptosis have been suggested to be interrelated in various human lung carcinomas. Leucine zipper EF-hand-containing transmembrane protein-1 (LETM1) was cloned in an attempt to identify candidate genes for Wolf-Hirschhorn syndrome. LETM1 plays a role in mitochondrial morphology, ion homeostasis, and cell viability. LETM1 has also been shown to be overexpressed in different human cancer tissues, including lung cancer. In the current study, we have provided clear evidence that LETM1 acts as an anchoring protein for the mitochondria-associated ER membrane (MAM). Fragmented mitochondria have been found in lung cancer cells with LETM1 overexpression. In addition, a reduction of mitochondrial membrane potential and significant accumulation of microtubule-associated protein 1 A/1B-light chain 3 punctate, which localizes with Red-Mito, was found in LETM1-overexpressed cells, suggesting that mitophagy is upregulated in these cells. Interestingly, glucose-regulated protein 78 kDa (GRP78; an ER chaperon protein) and glucose-regulated protein 75 kDa (GRP75) were posited to interact with LETM1 in the immunoprecipitated LETM1 of H460 cells. This interaction was enhanced in cells treated with carbonyl cyanide m-chlorophenylhydrazone, a chemical mitophagy inducer. Treatment of cells with honokiol (a GRP78 inhibitor) blocked LETM1-mediated mitophagy, and CRISPR/Cas9-mediated GRP75 knockout inhibited LETM1-induced autophagy. Thus, GRP78 interacts with LETM1. Taken together, these observations support the notion that the complex formation of LETM1/GRP75/GRP78 might be an important step in MAM formation and mitophagy, thus regulating mitochondrial quality control in lung cancer.

Hydroxyl Group-Targeted Conjugate and Its Self-Assembled Nanoparticle of Peptide Drug: Effect of Degree of Saturation of Fatty Acids and Modification of Physicochemical Properties.

Purpose: To conjugate different degree of saturation of C18 fatty acids (stearic acid, oleic acid, and linoleic acid) with the hydroxyl groups of leuprolide acetate (LEU acetate) and to investigate the controlled release and enhanced permeability through self-assembled nanoparticles (L18FNs). Methods: Yamaguchi esterification with benzoyl chloride and DMAP (4-Dimethylaminopyridine) allowed the conjugation of the fatty acid to the hydroxyl group of LEU. The three conjugates were then designated as stearic acid-conjugated LEU, LSC, oleic acid-conjugated LEU, LOC, and linoleic acid-conjugated LEU, LLC, respectively. The conjugates (L18FCs) were purified using preparative HPLC (Prep-HPLC) and identified through various instrumental analyses. Results: The zeta potential, particle size, and morphology of each L18FNs were evaluated. In the case of LSNs, the zeta potential value was relatively low and the particle size was larger than LONs and LLNs owing to the higher hydrophobicity of saturated fatty chain, while the LLNs showed a higher zeta potential and smaller particle size. In human plasma, LLC showed the fastest degradation rate with the highest accumulative drug release. The permeability of L18FNs was analyzed through the Franz diffusion cell experiment, confirming that the degree of saturation of fatty acids affects the permeability of LFNs. While the permeability of LSNs was not significantly enhanced due to higher particle size after nanonization, LONs and LLNs increased 1.56 and 1.85 times in permeation, respectively, compared to LEU. Conclusion: Utilization of different degree of saturation of fatty acids to conjugate a peptide drug could provide pharmaceutical versatility via self-assembly and modification of physicochemical properties.