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We demonstrate that covalent bonding between antibodies and TMDs results in hybrid materials that are remarkably stable. The most notable advantage is that the biosensor devices resist repeated washings without being damaged or losing sensitivity.

Organoids are a three-dimensional (3D) culture system that simulate actual organs. Therefore, tumor organoids are expected to predict precise response to chemotherapy in patients. However, to date, few studies have studied the drug responses in organoids of malignant mesothelioma (MM). The poor prognosis of MM emphasizes the importance of establishing a protocol for generating MM-organoid for research and clinical use. Here, we established murine MM organoids from p53+/-or wild-type C57BL/6 strain by intraperitoneal injection either with crocidolite or carbon nanotube. Established MM-organoids proliferated in Matrigel as spheroids. Subcutaneous injection assays revealed that the MM-organoids mimicked actual tissue architecture and maintained the original histological features of the primary MM. RNA sequencing and pathway analyses revealed that the significant expressional differences between the 2D- and 3D-culture systems were observed in receptor tyrosine kinases, including IGF1R and EGFR, glycosylation and cholesterol/steroid metabolism. MM-organoids exhibited a more sensitive response to cisplatin through stable plasma membrane localization of a major cisplatin transporter, copper transporter 1/Slc31A1 (Ctr1) in comparison to 2D-cultures, presumably through glycosylation and lipidation. The Matrigel culture system facilitated the localization of CTR1 on the plasma membrane, which simulated the original MMs and the subcutaneous xenografts. These results suggest that the newly developed protocol for MM-organoids is useful to study strategies to overcome chemotherapy resistance to cisplatin.

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Supplementary Table 2 from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma

Supplementary Figure 2 from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma

Supplementary Figure 3 from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma

Supplementary Figure 1 from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma

Supplementary Materials and Methods from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma

Supplementary Table 1 from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma

Supplementary Figure Legends 1-3 from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma

Ferroptosis is a new form of regulated non-apoptotic cell death, which is characterized by iron-dependent lipid peroxidation, leading eventually to plasma membrane rupture. Its core mechanisms have been elucidated consisting of a driving force as catalytic Fe(II)-dependent Fenton reaction and an incorporation of polyunsaturated fatty acids to membrane phospholipids via peroxisome-dependent and -independent pathways, whereas suppressing factors are the prevention of lipid peroxidation by glutathione peroxidase 4 to protect lipid peroxidation and direct membrane repair via coenzyme Q10 and ESCRT-III pathways. The significance of ferroptosis in cancer therapeutics has now been unveiled. Specific ferroptosis inducers are expected as a promising strategy for cancer treatment, especially in cancers with epithelial mesenchymal transition and possibly in cancers with activated Hippo signaling pathways, both of which cause resistance to traditional chemotherapy but tend to show ferroptosis susceptibility. Developments of ferroptosis inducers are in progress by nanotechnology-based drugs or by innovative engineering devices. Especially, low-temperature (non-thermal) plasma is a novel technology at the preclinical stage. The exposure can induce ferroptosis selectively in cancer cells which are generally rich in catalytic Fe(II). Here we summarize and discuss the recently uncovered responsible molecular mechanisms in association with iron metabolism, ferroptosis and cancer therapeutics. Finally, we also highlight the current classification of ferroptosis inducers.

Iron is an essential element for every life on earth as a primary media for electron flow. Sulfur compounds as sulfhydryls counteract catalytic activity of iron whereas sulfur overdose is also toxic. In aerobic organisms, oxygen is the major media for electron transfer with higher intracellular mobility, which cooperates with the iron system. Based on the importance of iron, there is no active pathway to excrete iron outside the body in higher species. Whereas bacterial infection causes a scramble for iron in situ, cancer can be the outcome of the side effects of long use of iron and oxygen. Ferroptosis is a recently coined cell death, defined as catalytic Fe(II)-dependent regulated necrosis accompanied by lipid peroxidation. Researchers recently recognized that ferroptosis is involved in a variety of physiological and pathological contexts, including embryonic erythropoiesis, aging, neurodegeneration and cancer cell death. Alternatively, carcinogenesis is a process to obtain iron addiction with ferroptosis-resistance, based on rodent animal studies. Here we propose that ferroptosis is three-dimensionally regulated by iron, sulfur and oxygen, which correspond to oxidants, antioxidants and membrane fluidity with susceptibility to lipid peroxidation, respectively. Whereas life attempts to prevent ferroptosis, ferroptotic cells eventually emit iron-loaded ferritin as extracellular vesicles to maintain monopoly of iron.

COVID-19 is pandemic since 2020 and further information is necessary on the risk factors associated with the infection of SARS-CoV-2. As an entry mechanism, SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) as receptor and transmembrane serine protease 2 (TMPRSS2) to activate fusion with host plasma membrane. Because dysgeusia is an early symptom of COVID-19, we here studied the expression of ACE2 and TMPRSS2 in the tongue and the associated tissues of mice and humans with immunohistochemistry and immunoblot analysis. ACE2 expression was low in the human tongue but was observed in the squamous epithelium, perineurium, arterial wall, salivary glands as well as taste buds. In contrast, mice showed high expression. In sharp contrast, TMPRSS2 expression was high in all the cells mentioned above in humans but relatively low in mice except for salivary glands. We then performed semi-quantitation of immunohistochemistry data of human ACE2 and TMPRSS2 and analyzed for age, sex, alcohol intake, and smoking habit with logistic regression analysis. We found that alcohol intake and female gender were the significant risk factors for increasing TMPRSS2 expression. In conclusion, TMPRSS2 is an important factor to be considered regarding SARS-CoV-2 entry and amplification in the oral cavity, which is promoted through drinking habit.

Human epidemiological and animal studies have demonstrated that excess iron is a risk for cancer. The responsible mechanisms are: 1) increased intracellular iron catalyzes the Fenton reaction to generate hydroxyl radicals, leading to mutagenic oxidative DNA lesions; 2) iron is necessary for cellular proliferation as cofactors of many enzymes. Thus, iron-excess milieu promotes selecting cellular evolution to ferroptosis-resistance, a major basis for carcinogenesis. Ferritin is a 24-subunit nanocage protein required for iron storage under the regulation of the iron-regulatory protein (IRP)/iron-responsive element (IRE) system. Ferritin is a serum marker, representing total body iron storage. However, how ferritin is secreted extracellularly has been unelucidated. We recently discovered that an exosomal marker CD63 is regulated by the IRP/IRE system and that iron-loaded ferritin is secreted as extracellular vesicles under the guidance of nuclear receptor coactivator 4 (NCOA4). On the other hand, we found that macrophages under asbestos-induced ferroptosis emit ferroptosis-dependent extracellular vesicles (FedEVs), which are received by nearby mesothelial cells, resulting in significant mutagenic DNA damage. Therefore, cells, including macrophages, can share excess iron with other cells, via iron-loaded ferritin packaged in extracellular vesicles as safe non-catalytic iron. However, similar process, such as one involving FedEVs, may cause accumulation of excess iron in other specific cells, which may eventually promote carcinogenesis.

Low-temperature plasma (LTP) is a partially ionized gas that contains electrons, ions, radicals, light, etc. Recently, the bio-medical application of LTP has become a hot topic in plasma science and biological science. Cancer treatment with plasma is the most challenging topic in plasma bio-medical applications. Many in vitro and in vivo experiments have been conducted to investigate the anti-tumor effects of LTP. Extracellular reactive oxygen and nitrogen species (RONS) in plasma-activated solutions are key factors for the anti-tumor effects, and amino acid modifications by LTP may affect cellular responses. Intracellular RONS are also key factors for the anti-tumor effects. Various signaling pathways, such as p53 signaling pathways, survival and proliferation signaling pathways, and oxidative stress-dependent signaling pathways are activated by LTP.

Cancer susceptibility is a critical factor in the understanding of carcinogenesis. Intraperitoneal (i.p.) injection of an iron chelate, ferric nitrilotriacetate (Fe‐NTA), produces hydroxyl radicals via Fenton reaction to induce ferroptosis in renal proximal tubules. Rats or mice subjected to repeated i.p. injections of Fe‐NTA develop renal cell carcinoma (RCC). To elucidate the molecular mechanisms that cause susceptibility to renal carcinogenesis, we first established an inter‐strain difference in the susceptibility to Fe‐NTA‐induced renal carcinogenesis in mice. Based on a previous observation of a low incidence of RCC with this model in C57BL/6J strain mice, we investigated A/J strain mice here, which demonstrated significantly higher susceptibility to Fe‐NTA‐induced renal carcinogenesis. Homozygous deletion of the Cdkn2a/2b tumor suppressor locus was detected for the first time in A/J strain mice. Focusing on ferroptosis and iron metabolism, we explored the mechanisms involved that lead to the difference in RCC development. We compared the protective responses in the kidney of A/J and C57BL/6J strains after Fe‐NTA treatment. After 3‐week Fe‐NTA treatment, A/J mice maintained higher levels of expression of glutathione peroxidase 4 and xCT (SLC7A11), leading to a lower level of lipid peroxidation. Simultaneously, A/J mice had decreased expression of transferrin receptor and increased expression of ferritin to greater degrees than C57BL/6 mice. After a single Fe‐NTA injection, higher levels of oxidative cell damage and cytosolic catalytic Fe(II) were observed in C57BL/6J mice, accompanied by a greater increase in lipocalin‐2. Lipocalin‐2 deficiency significantly decreased oxidative renal damage. Our results suggest that a genetic trait favoring ferroptosis resistance contributes to high susceptibility to Fe‐NTA‐induced RCC in A/J strain., Cancer susceptibility is an important issue when considering cancer prevention. In this paper, we used an iron‐mediated oxidative stress‐induced renal carcinogenesis model in mice and found that ferroptosis resistance is an important factor determining cancer susceptibility.

Cancer is the primary cause of human mortality in Japan since 1981. Although numerous novel therapies have been developed and applied in clinics, the number of deaths from cancer is still increasing worldwide. It is time to consider the strategy of cancer prevention more seriously. Here we propose a hypothesis that cancer can be side effects of long time-use of iron and oxygen and that carcinogenesis is an evolution-like cellular events to obtain “iron addiction with ferroptosis-resistance” where genes and environment interact each other. Among the recognized genetic risk factors for carcinogenesis, we here focus on BRCA1 tumor suppressor gene and how environmental factors, including daily life exposure and diets, may impact toward carcinogenesis under BRCA1 haploinsufficiency. Although mice models of BRCA1 mutants have not been successful for decades in generating phenotype mimicking the human counterparts, a rat model of BRCA1 mutant was recently established that reasonably mimics the human phenotype. Two distinct categories of oxidative stress, one by radiation and one by iron-catalyzed Fenton reaction, promoted carcinogenesis in Brca1 rat mutants. Furthermore, mitochondrial damage followed by alteration of iron metabolism finally resulted in ferroptosis-resistance of target cells in carcinogenesis. These suggest a possibility that cancer prevention by active pharmacological intervention may be possible for BRCA1 mutants to increase the quality of their life rather than preventive mastectomy and/or oophorectomy.

Cold atmospheric pressure plasmas are promising medical tools that can assist in cancer treatment. While the medical pathology mechanism is substantially understood, knowledge of the contribution of reactive species formed in plasma and the mode of activation of biochemical pathways is insufficient. Herein, we present a concept involving antitumoral plasma-activated organics, which is envisaged to increase cytotoxicity levels against cancer cells. Ringer′s acetate solution was irradiated by low-temperature plasma at atmospheric pressure and possible reaction pathways of the compound generation are presented. The chemical compounds formed by plasma treatment and their effects on non-tumorigenic breast epithelial cells (MCF-10A) and breast cancer cells (MCF-7) were investigated. The cell viability results have shown that plasma-derived compounds have both, stimulatory and inhibitory effects on cell viability, depending on the concentration of the generated compounds in the irradiated liquids. Previous studies have shown that oxidative stresses involving reactive oxygen and nitrogen species (RONS) can be used to kill cancer cells. Hence, while RONS offers promising first-step killing effects, cell viability results have shown that plasma-derived compounds, such as acetic anhydride and ethyl acetate, have the potential to play important roles in plasma-based cancer therapy.

Non-thermal plasma (NTP) induces the generation of reactive oxygen species (ROS) and reactive nitrogen species, such as hydroxyl radicals (

Malignant mesothelioma (MM) is still a social burden associated with asbestos exposure. Local iron accumulation thereby represents the major pathogenesis, followed by oxidative DNA strand breaks and genomic alterations in the mesothelium. BRCA1 is a critical component of homologous recombination repair directed to DNA double-strand breaks. Whereas BRCA1 germline mutation is an established risk for breast/ovarian cancer, its role in MM development remains to be elucidated. Murine Brca1 mutant models thus far have not reproduced human phenotypes. However, a rat Brca1 mutant model (Mut; L63X/+) recently reproduced them at least partially. Here we describe the differential induction of MM in Brca1 mutant rats by intraperitoneal injection of chrysotile or crocidolite. Only Mut males injected with chrysotile revealed a promotional effect on mesothelial carcinogenesis in comparison to wild-type and/or females, with all the MMs Brca1-haploinsufficient. Array-based comparative genomic hybridization of MMs disclosed a greater extent of chromosomal deletions in Brca1 mutants, including Cdkn2a/2b accompanied by Tfr2 amplification, in comparison to wild-type tumors. Mutant MMs indicated iron metabolism dysregulation, such as increase in catalytic Fe(II) and Ki67-index as well as decrease in Fe(III) and ferritin expression. Simultaneously, mutant MMs revealed ferroptosis-resistance by upregulation of Slc7A11 and Gpx4. At an early carcinogenic stage of 4 weeks, induced Brca1 expression in mesothelial cells was significantly suppressed in chrysotile/Mut in comparison to crocidolite/Mut whereas significant preference to iron with decrease in Fe(III) has been already established. In conclusion, chrysotile exposure can be a higher risk for MM in BRCA1 mutant males, considering the rat results.

Extracellular vesicles (EVs) transfer functional molecules between cells. CD63 is a widely recognized EV marker that contributes to EV secretion from cells. However, the regulation of its expression remains largely unknown. Ferritin is a cellular iron storage protein that can also be secreted by the exosome pathway, and serum ferritin levels classically reflect body iron stores. Iron metabolism–associated proteins such as ferritin are intricately regulated by cellular iron levels via the iron responsive element-iron regulatory protein (IRE-IRP) system. Herein, we present a novel mechanism demonstrating that the expression of the EV-associated protein CD63 is under the regulation of the IRE-IRP system. We discovered a canonical IRE in the 5′ untranslated region of CD63 messenger RNA that is responsible for regulating its expression in response to increased iron. Cellular iron loading caused a marked increase in CD63 expression and the secretion of CD63+ EVs from cells, which were shown to contain ferritin-H and ferritin-L. Our results demonstrate that under iron loading, intracellular ferritin is transferred via nuclear receptor coactivator 4 (NCOA4) to CD63+ EVs that are then secreted. Such iron-regulated secretion of the major iron storage protein ferritin via CD63+ EVs, is significant for understanding the local cell-to-cell exchange of ferritin and iron.

Old animals display significant alterations in sleep-wake patterns such as increases in sleep fragmentation and sleep propensity. Here we demonstrated that dorsomedial hypothalamus-specific PR-domain containing protein 13-knockout (DMH-Prdm13-KO) mice recapitulated age-associated sleep alterations such as sleep fragmentation and increased sleep attempts during sleep deprivation (SD). These phenotypes were further exacerbated during aging, with increased adiposity and decreased physical activity, resulting in shortened lifespan. Dietary restriction (DR), a well-known anti-aging intervention in diverse organisms, ameliorated age-associated sleep alterations, whereas these effects of DR were abrogated in DMH-Prdm13-KO mice. Moreover, overexpression of Prdm13 in the DMH ameliorated sleep fragmentation and excessive sleepiness during SD in old mice. Therefore, maintaining Prdm13 signaling in the DMH might play an important role to control sleep-wake patterns during aging.

Low-temperature plasma (LTP) is a promising tool for cancer treatment because irradiated various solutions show selective antitumoral effects on cancer cells. In this study, Ringer`s lactate solution was irradiated by pulsed electrical discharges ignited in argon, nitrogen, and oxygen gas mixtures. The chemical compounds formed by LTP and their effects on non-tumorigenic breast epithelial cells (MCF-10A) and breast cancer cells (MCF-7) were investigated. Among these compounds, glyceric acid increased the cell viability by more than two-fold compared to the control samples for MCF-10A and MCF-7 cells, whereas the tricarballylic acid had a pronounced cytotoxic effect on the cells when incubated with solutions of 0.6 mM to 50 mM concentrations. The results show that the LTP-generated chemical compounds have both, stimulatory and inhibitory effects on cell viability, possibly by influencing the morphology of the cells and physiological functions, depending on the concentration of the generated compounds in the irradiated liquids.

Cellular senescence and cell competition are important tumor suppression mechanisms that restrain cells with oncogenic mutations at the initial stage of cancer development. However, the link between cellular senescence and cell competition remains unclear. Senescent cells accumulated during the in vivo aging process contribute toward age-related cancers via the development of senescence-associated secretory phenotype (SASP). Here, we report that hepatocyte growth factor (HGF), a SASP factor, inhibits apical extrusion and promotes basal protrusion of Ras-mutated cells in the cell competition assay. Additionally, cellular senescence induced by a high-fat diet promotes the survival of cells with oncogenic mutations, whereas crizotinib, an inhibitor of HGF signaling, provokes the removal of mutated cells from mouse livers and intestines. Our study provides evidence that cellular senescence inhibits cell competition-mediated elimination of oncogenic cells through HGF signaling, suggesting that it may lead to cancer incidence during aging.

Germline-mutation in BRCA1 tumor suppressor gene is an established risk for carcinogenesis not only in females but also in males. Deficiency in the repair of DNA double-strand breaks is hypothesized as a responsible mechanism for carcinogenesis. However, supporting data is insufficient both in the mutation spectra of cancers in the patients with BRCA1 germline-mutation and in murine knockout/knock-in models of Brca1 haploinsufficiency. Furthermore, information on the driving force toward carcinogenesis in BRCA1 mutation carriers is lacking. Here we applied Fenton reaction-based renal carcinogenesis to a rat heterozygously knockout model of BRCA1 haploinsufficiency (mutant [MUT] model; L63X/+). Rat MUT model revealed significant promotion of renal cell carcinoma (RCC) induced by ferric nitrilotriacetate (Fe-NTA). Array-based comparative genome hybridization of the RCCs identified significant increase in chromosomal amplification, syntenic to those in breast cancers of BRCA1 mutation carriers, including c-Myc, in comparison to those in the wild-type. Subacute-phase analysis of the kidney after repeated Fe-NTA treatment in the MUT model revealed dysregulated iron metabolism with mitochondrial malfunction assessed by expression microarray and electron microscopy, leading to renal tubular proliferation with iron overload. In conclusion, we for the first time demonstrate that biallelic wild-type BRCA1 provides more robust protection for mitochondrial metabolism under iron-catalyzed oxidative stress, preventing the emergence of neoplastic cells with chromosomal amplification. Our results suggest that oxidative stress via excess iron is a major driving force for carcinogenesis in BRCA1 haploinsufficiency, which can be a target for cancer prevention and therapeutics.

Thioredoxin, encoded by Txn1, acts as a critical antioxidant in the defense against oxidative stress by regulating the dithiol/disulfide balance of interacting proteins. The role of thioredoxin in the central nervous system (CNS) is largely unknown. A phenotype-driven study of N-ethyl-N-nitrosourea-mutated rats with wild-running seizures revealed the importance of Txn1 mutations in CNS degeneration. Genetic mapping identified Txn1-F54L in the epileptic rats. The insulin-reducing activity of Txn1-F54L was approximately one-third of that of the wild-type (WT). Bilateral symmetrical vacuolar degeneration in the midbrain, mainly in the thalamus and the inferior colliculus, was observed in the Txn1-F54L rats. The lesions displayed neuronal and oligodendrocytic cell death. Neurons in Txn1-F54L rats showed morphological changes in the mitochondria. Vacuolar degeneration peaked at five weeks of age, and spontaneous repair began at seven weeks. The TUNEL assay showed that fibroblasts derived from homozygotes were susceptible to cell death under oxidative stress. In five-week-old WT rats, energy metabolism in the thalamus was significantly higher than that in the cerebral cortex. In conclusion, in juvenile rats, Txn1 seems to play an essential role in reducing oxidative stress in the midbrains with high energy metabolism.

Superoxide dismutase 1 (Sod1) plays pivotal roles in antioxidation via accelerating the conversion of superoxide anion radicals into hydrogen peroxide, thus inhibiting the subsequent radical chain reactions. While Sod1 deficient cells inevitably undergo death in culture conditions, Sod1-knockout (KO) mice show relatively mild phenotypes and live approximately two years. We hypothesized that the presence of abundant levels of ascorbic acid (AsA), which is naturally produced in mice, contributes to the elimination of reactive oxygen species (ROS) in Sod1-KO mice. To verify this hypothesis, we employed mice with a genetic ablation of aldehyde reductase (Akr1a), an enzyme that is involved in the biosynthesis of AsA, and established double knockout (DKO) mice that lack both Sod1 and Akr1a. Supplementation of AsA (1.5 mg/ml in drinking water) was required for the DKO mice to breed, and, upon terminating the AsA supplementation, they died within approximately two weeks regardless of age or gender. We explored the etiology of the death from pathophysiological standpoints in principal organs of the mice. Marked changes were observed in the lungs in the form of macroscopic damage after the AsA withdrawal. Histological and immunological analyses of the lungs indicated oxidative damage of tissue and activated immune responses. Thus, preferential oxidative injury that occurred in pulmonary tissues appeared to be primary cause of the death in the mice. These collective results suggest that the pivotal function of AsA in coping with ROS in vivo, is largely in pulmonary tissues that are exposed to a hyperoxygenic microenvironment.

Malignant mesothelioma (MM) is one of the most lethal tumors in humans. The onset of MM is linked to exposure to asbestos, which generates reactive oxygen species (ROS). ROS are believed to be derived from the frustrated phagocytosis and the iron in asbestos. To explore the pathogenesis of MM, peritoneal MM was induced in rats by the repeated intraperitoneal injection of iron saccharate and nitrilotriacetate. In the present study, we used microarray techniques to screen the microRNA (miR) expression profiles of these MM. We observed that the histological subtype impacted the hierarchical clustering of miR expression profiles and determined that miR‐199/214 is a distinctive feature of iron saccharate‐induced sarcomatoid mesothelioma (SM). Twist1, a transcriptional regulator of the epithelial‐mesenchymal transition, has been shown to activate miR‐199/214 transcription; thus, the expression level of Twist1 was examined in iron‐induced and asbestos‐induced mesotheliomas in rats. Twist1 was exclusively expressed in iron saccharate‐induced SM but not in the epithelioid subtype. The Twist1‐miR‐199/214 axis is activated in iron saccharate‐induced and asbestos‐induced SM. The expression levels of miR‐214 and Twist1 were correlated in an asbestos‐induced MM cell line, suggesting that the Twist1‐miR‐199/214 axis is preserved. MeT5A, an immortalized human mesothelial cell line, was used for the functional analysis of miR. The overexpression of miR‐199/214 promoted cellular proliferation, mobility and phosphorylation of Akt and ERK in MeT5A cells. These results indicate that miR‐199/214 may affect the aggressive biological behavior of SM., Malignant mesothelioma (MM) is one of the most lethal tumors. Its independent prognostic factors include younger age, female sex, epithelioid subtype and low clinical stage. Hierarchical clustering of miR expression profiles was impacted by the histological subtypes in rat MM. Sarcomatoid mesothelioma (SM), which is a worse prognostic factor, overexpressed miR‐199/214 in iron saccharate‐induced MM. The miR‐199/214‐Twist1 axis was activated in iron‐induced and asbestosinduced SM. Overexpression of miR‐199/214 promoted cellular proliferation, mobility and phosphorylation of Akt and ERK.

The onset of malignant mesothelioma (MM) is linked to exposure to asbestos fibers. Asbestos fibers are classified as serpentine (chrysotile) or amphibole, which includes the crocidolite, amosite, anthophyllite, tremolite, and actinolite types. Although few studies have been undertaken, anthophyllite has been shown to be associated with mesothelioma, and tremolite, a contaminant in talc and chrysotile, is a risk factor for carcinogenicity. Here, after characterizing the length and width of these fibers by scanning electron microscopy, we explored the cytotoxicity induced by tremolite and anthophyllite in cells from an immortalized human mesothelial cell line (MeT5A), murine macrophages (RAW264.7), and in a rat model. Tremolite and short anthophyllite fibers were phagocytosed and localized to vacuoles, whereas the long anthophyllite fibers were caught on the pseudopod of the MeT5A and Raw 264.7 cells, according to transmission electron microscopy. The results from a 2‐day time‐lapse study revealed that tremolite was engulfed and damaged the MeT5A and RAW264.7 cells, but anthophyllite was not cytotoxic to these cells. Intraperitoneal injection of tremolite in rats induced diffuse serosal thickening, whereas anthophyllite formed focal fibrosis and granulomas on peritoneal serosal surfaces. Furthermore, the loss of Cdkn2a/2b, which are the most frequently lost foci in human MM, were observed in 8 cases of rat MM (homozygous deletion [5/8] and loss of heterozygosity [3/8]) by array‐based comparative genomic hybridization techniques. These results indicate that tremolite initiates mesothelial injury and persistently frustrates phagocytes, causing subsequent peritoneal fibrosis and MM. The possible mechanisms of carcinogenicity based on fiber diameter/length are discussed., MeT5A (immortalized mesothelial cells) and RAW264.7 (macrophage lineage cells) were damaged by tremolite but not anthophyllite. Tremolite induced diffuse peritoneal thickening, whereas anthophyllite induced focal fibrosis. Furthermore, tremolite‐induced malignant mesothelioma frequently lost Cdkn2a/2b.

Exposure to asbestos fiber is central to mesothelial carcinogenesis. Recent sequencing studies on human and rodent malignant mesothelioma (MM) revealed frequently mutated genes, including CDKN2A, B...

Molecular hydrogen (HExhaled HOur prospective observational study revealed that maternal production of HMeasuring maternal H

Any independent life requires iron to survive. Whereas iron deficiency causes oxygen insufficiency, excess iron is a risk for cancer, generating a double-edged sword. Iron metabolism is strictly regulated via specific systems, including iron-responsive element (IRE)/iron regulatory proteins (IRPs) and the corresponding ubiquitin ligase FBXL5. Here we briefly reflect the history of bioiron research and describe major recent advancements. Ferroptosis, a newly coined Fe(II)-dependent regulated necrosis, is providing huge impact on science. Carcinogenesis is a process to acquire ferroptosis-resistance and ferroptosis is preferred in cancer therapy due to immunogenicity. Poly(

Diagnostic markers of malignant mesothelioma (MM) have been extensively investigated. Immunohistochemistry (IHC) markers, such as calretinin, have been used for pathologic diagnosis. However, more diagnostic markers are required to improve the specificity and sensitivity of pathologic diagnosis. This study proposed two proteins as diagnostic markers for epithelioid MM. One is RhoA, an MM mutation-susceptible locus-derived protein, and another is vigilin, a lung small cell carcinoma marker. IHC was performed using 93 MM (epithelioid, 71 cases; sarcomatoid, 13 cases; and biphasic, 9 cases), 64 lung adenocarcinoma (LAC), 60 lung squamous cell carcinoma (LSC), and 14 normal mesothelial (NM) tissues. The majority of epithelioid MM cases were positive for both RhoA and vigilin, whereas both IHCs showed lower stainability in biphasic and sarcomatoid MM. Besides, both IHCs showed significantly higher stainability for RhoA and vigilin in epithelioid MM than in LAC and LSC (p p > 0.05). In the differential diagnosis of MM from lung cancer, the accuracy and specificity of RhoA, vigilin, and calretinin staining were almost equivalent. Further, H-score test showed that there was no significant difference between RhoA versus calretinin and vigilin versus calretinin in IHC positivity in epithelioid MM (p > 0.05). In conclusion, RhoA and vigilin may be candidates for immunohistochemical markers for epithelioid MM.

Old animals display significant alterations in sleep–wake patterns such as increases in sleep fragmentation and sleep propensity. Here, we demonstrated that PR-domain containing protein 13 (Prdm13)+ neurons in the dorsomedial hypothalamus (DMH) are activated during sleep deprivation (SD) in young mice but not in old mice. Chemogenetic inhibition of Prdm13+ neurons in the DMH in young mice promotes increase in sleep attempts during SD, suggesting its involvement in sleep control. Furthermore, DMH-specificPrdm13-knockout (DMH-Prdm13-KO) mice recapitulated age-associated sleep alterations such as sleep fragmentation and increased sleep attempts during SD. These phenotypes were further exacerbated during aging, with increased adiposity and decreased physical activity, resulting in shortened lifespan. Dietary restriction (DR), a well-known anti-aging intervention in diverse organisms, ameliorated age-associated sleep fragmentation and increased sleep attempts during SD, whereas these effects of DR were abrogated in DMH-Prdm13-KO mice. Moreover, overexpression ofPrdm13in the DMH ameliorated increased sleep attempts during SD in old mice. Therefore, maintaining Prdm13 signaling in the DMH might play an important role to control sleep–wake patterns during aging.

Malignant mesothelioma (MM) is still increasing worldwide. The pathogenesis depends on asbestos-induced iron accumulation, which eventually leads to ferroptosis-resistance of mesothelial cells via somatic mutations. Poly (rC)-binding proteins 1 and 2 (PCBP1/2) are recently recognized cytosolic Fe(II) chaperones. Here we studied the role of PCBP1/2 in rat/human mesothelial and MM cells as well as rat/human MM specimens. Normal peritoneal mesothelial cells in rats exhibited PCBP1 but not PCBP2 immunopositivity whereas primary/immortalized mesothelial cells showed PCBP1/2 immunopositivity. Rat MM specimens induced by intraperitoneal injection of chrysotile, including in situ lesion, revealed PCBP1/2 immunopositivity (90% for both) in the nucleus and cytoplasm with a tendency of higher expression in epithelioid subtype. Knockdown of PCBP2 but not PCBP1 significantly decreased both TfR1 and FTH expression in MM cells with inhibition of proliferation, indicating stagnation of intracellular iron transport. Erastin, a cysteine-deprivation type ferroptosis inducer, decreased the expression of both PCBP1/2 in MM cells. Furthermore, PCBP2 knockdown significantly increased the sensitivity of MM cells to erastin-induced ferroptosis with increased catalytic Fe(II). In conclusion, PCBP2 works for ferroptosis-resistance not only during mesothelial carcinogenesis but also in MM, which warrants further investigation as a novel therapeutic target.

Congenital malformations cause life-threatening diseases in pediatrics, yet the molecular mechanism of organogenesis is poorly understood. Here we show that Dyrk2-deficient mice display congenital malformations in multiple organs. Transcriptome analysis reveals molecular pathology of Dyrk2-deficient mice, particularly with respect to Foxf1 reduction. Mutant pups exhibit sudden death soon after birth due to respiratory failure. Detailed analyses of primordial lungs at the early developmental stage demonstrate that Dyrk2 deficiency leads to altered airway branching and insufficient alveolar development. Furthermore, the Foxf1 expression gradient in mutant lung mesenchyme is disrupted, reducing Foxf1 target genes, which are necessary for proper airway and alveolar development. In ex vivo lung culture system, we rescue the expression of Foxf1 and its target genes in Dyrk2-deficient lung by restoring Shh signaling activity. Taken together, we demonstrate that Dyrk2 is essential for embryogenesis and its disruption results in congenital malformation., Yogosawa et al find that mice lacking the Dyrk2 kinase display congenital malformations in multiple organs and die from respiratory failure associated with disrupted lung mesenchyme and reduced expression of Foxf1. Using an ex vivo lung culture system, they rescue the expression of Foxf1 and its target by restoring Shh signalling, altogether providing insights into Dyrk2 function.

The 17th Annual Meeting of the Society for Free Radical Research India (SFRR-INDIA-2020) and its associated conference on “Role and Management of Oxidative Stress in Human Disease” was held under t...

Thioredoxin (TXN), encoded by Txn1, acts as a critical antioxidant in the defense against oxidative stress by regulating the dithiol/disulfide balance of interacting proteins. The role of TXN in the central nervous system (CNS) is largely unknown. A phenotype-driven study of N-ethyl-N-nitrosourea-mutated rats with running seizures at around five-week of age revealed the relevance of Txn1 mutations to CNS disorders. Genetic mapping identified Txn1-F54L in epileptic rats. The insulin-reducing activity of Txn1-F54L rats was approximately one-third that of the wild-type. Vacuolar degeneration in the midbrain, mainly in the thalamus and the inferior colliculus, was observed in the Txn1-F54L rats. The lesions displayed neuronal and oligodendrocyte cell death. Neurons in Txn1-F54L rats showed morphological changes in the mitochondria. Vacuolar degeneration began at three weeks of age, and spontaneous repair began at seven weeks; a dramatic change from cell death to repair occurred in the midbrain during a restricted period. In conclusion, Txn1 is essential for the development of the midbrain in juvenile rats.

Smoke from conventional cigarettes (C-cigarettes) contains various reactive oxygen species and toxic chemicals, which potentially cause oxidative damage not only to airways but also to the whole body, leading eventually to diseases, including emphysema, advanced atherosclerosis, and cancer. Many heat-not-burn tobacco products (HTPs) have been commercialized recently in Japan to maintain the smoking population by advertising that HTPs are less toxic. However, there were few studies reported from neutral organizations whether HTPs are indeed less damaging. To evaluate the potential capacity of HTPs to induce oxidative stress, we here compared two different HTPs with two types of C-cigarettes, using human fibroblast IMR90SV cells and 5% aqueous extracts in 10-ml phosphate-buffered saline (50-ml smoke/10 s). HTPs exhibited significantly lower oxidative toxicity in comparison to C-cigarettes. Whereas C-cigarettes induced ferroptosis in fibroblasts, the effects of HTPs were significantly reduced by measuring the levels of peroxides, pro-inflammatory cytokine expression, autophagy, catalytic Fe(II) and 8-hydroxy-2'-deoxyguanosine. Notably, major portions of C-cigarettes-induced pathogenic responses were inhibited by catalase. However, HTPs still induced p62 autophagy-adaptor at 5%-dilution and caused lethal effects to fibroblasts with undiluted solution. In conclusion, HTPs smoke