RANK/RANKL axis promotes migration, invasion, and metastasis of osteosarcoma via activating NF-κB pathway

Osteosarcoma (OS) is one of the most prevalent primary bone tumors with a high degree of metastasis and poor prognosis. Epithelial-to-mesenchymal transition (EMT) is a cellular mechanism that contributes to the invasion and metastasis of cancer cells, and OS cells have been reported to exhibit EMT-like characteristics. Our previous studies have shown that the interaction between tumor necrosis factor superfamily member 11 (TNFRSF11A; also known as RANK) and its ligand TNFSF11 (also known as RANKL) promotes the EMT process in breast cancer cells. However, whether the interaction between RANK and RANKL enhances aggressive behavior by inducing EMT in OS cells has not yet been elucidated. In this study, we showed that the interaction between RANK and RANKL increased the migration, invasion, and metastasis of OS cells by promoting EMT. Importantly, we clarified that the RANK/RANKL axis induces EMT by activating the nuclear factor-kappa B (NF-κB) pathway. Furthermore, the NF-κB inhibitor dimethyl fumarate (DMF) suppressed migration, invasion, and EMT in OS cells. Our results suggest that the RANK/RANKL axis may serve as a potential tumor marker and promising therapeutic target for OS metastasis. Furthermore, DMF may have clinical applications in the treatment of lung metastasis in patients with OS.

Associations between negative and positive automatic thoughts and clinical variables in patients with schizophrenia

This study investigated the relationships between negative and positive automatic thoughts and clinical variables in patients with schizophrenia. The participants included 36 patients with schizophrenia (male = 16; female = 20; age = 42.86 ± 9.40) who were outpatients in the Department of Psychiatry at Tokushima University Hospital. We used the Automatic Thoughts Questionnaire-Revised (ATQ-R), Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale for Schizophrenia (CDSS), and Brief Assessment of Cognition in Schizophrenia (BACS) to assess negative and positive automatic thoughts, positive and negative symptoms, depressive symptoms, and neurocognition, respectively. Spearman rank correlation coefficients were calculated to determine the relationships between negative and positive automatic thoughts and clinical variables. No relationship was observed between negative and positive automatic thoughts. Negative automatic thoughts were related to depressive symptoms. Positive automatic thoughts were related to neurocognition. We therefore surmise that each automatic thought might have different clinical features and outcomes, and should therefore be treated accordingly.

Organogermanium, Ge-132, promotes the clearance of senescent red blood cells via macrophage-mediated phagocyte activation

Red blood cells (RBCs) are renewed in a cyclic manner. Aging RBCs are captured and degraded by phagocytic cells, and heme metabolic pigments are subsequently excreted in feces. We evaluated the effect of an organogermanium compound on RBC metabolism and found that the phagocytosis of RAW264.7 macrophage-like cells was increased by treatment with 3-(trihydroxygermyl)propanoic acid (THGP). Additionally, consumption of Ge-132 (a dehydrate polymer of THGP) changed the fecal color to bright yellow and increased the erythrocyte metabolic pigment levels and antioxidant activity in feces. These data suggest that Ge-132 may activate macrophages in the body and promote the degradation of aged RBCs. Furthermore, Ge-132 intake promoted not only increases in RBC degradation but also the induction of erythroblast differentiation in bone marrow cells. The normal hematocrit levels were maintained due to the maintenance of homeostasis, even though Ge-132 ingestion increased erythrocyte degradation. Therefore, Ge-132 enhances the degradation of senescent RBCs by macrophages. In turn, RBC production is increased to compensate for the amount of degradation, and RBC metabolism is increased.

HER3/Akt/mTOR pathway is a key therapeutic target for the reduction of triple‑negative breast cancer metastasis via the inhibition of CXCR4 expression

Triple‑negative breast cancer (TNBC), a highly metastatic subtype of breast cancer, and it has the worst prognosis among all subtypes of breast cancer. However, no effective systematic therapy is currently available for TNBC metastasis. Therefore, novel therapies targeting the key molecular mechanisms involved in TNBC metastasis are required. The present study examined whether the expression levels of human epidermal growth factor receptor 3 (HER3) were associated with the metastatic phenotype of TNBC, and evaluated the potential of HER3 as a therapeutic target in vitro and in vivo. A new highly metastatic 4T1 TNBC cell line, termed 4T1‑L8, was established. The protein expression levels in 4T1‑L8 cells were measured using luminex magnetic bead assays and western blot analysis. The HER3 expression levels and distant metastasis‑free survival (DMFS) in TNBC were analyzed using Kaplan‑Meier Plotter. Transwell migration and invasion assays were performed to detect migration and invasion. The anti‑metastatic effects were determined in an experimental mouse model of metastasis. The results revealed that the increased expression of the HER3/Akt/mTOR pathway was associated with a greater level of cell migration, invasion and metastasis of TNBC cells. In addition, it was found that high expression levels of HER3 were associated with a poor DMFS. The inhibition of the HER3/Akt/mammalian target of rapamycin (mTOR) pathway decreased the migration, invasion and metastasis of TNBC cells by decreasing the expression of C‑X‑C chemokine receptor type 4 (CXCR4). Furthermore, treatment of metastatic TNBC cells with everolimus inhibited their migration, invasion and metastasis by decreasing CXCR4 expression. Thus, targeting the HER3/Akt/mTOR pathway opens up a new avenue for the development of therapeutics against TNBC metastasis; in addition, everolimus may prove to be an effective therapeutic agent for the suppression of TNBC metastasis.

Bim downregulation by activation of NF-κB p65, Akt, and ERK1/2 is associated with adriamycin and dexamethasone resistance in multiple myeloma cells

Multiple myeloma (MM) frequently acquires multidrug resistance (MDR), which is due to poor prognosis. Our previous study indicated that high expression of Survivin and multidrug resistance protein 1 (MDR1) and decreased expression of Bim are associated with MDR in adriamycin- and dexamethasone-resistant cells. However, the fundamental mechanism of MDR in adriamycin- and dexamethasone-resistant MM cells is still unidentified. In this study, we examined the MDR mechanism in adriamycin- and dexamethasone-resistant cells. RPMI8226/ADM, ARH-77/ADM, RPMI8226/DEX, and ARH-77/DEX cells exhibited enhanced nuclear factor κB (NF-κB) p65, Akt, and extracellular signal-regulated kinase 1/2 (ERK1/2) activation. Combination treatment with NF-κB p65, phosphoinositide 3-kinase (PI3K), and mitogen-activated protein kinase 1/2 (MEK1/2) inhibitors resensitized to adriamycin and dexamethasone via increased Bim expression. Although treatment with MDR1 or Survivin siRNA did not overcome adriamycin and dexamethasone resistance in RPMI8226/ADM and RPMI8226/DEX cells, administration of Bim siRNA induced adriamycin and dexamethasone resistance in RPMI8226 cells. Moreover, low expression of Bim was related to poor prognosis in MM patients. These results indicate that activation of NF-κB p65, Akt, and ERK1/2 is associated with adriamycin and dexamethasone resistance via decreasing Bim expression, and these signal inhibitor combinations overcome drug resistance in MM. These findings suggest that combination treatment with these inhibitors and adriamycin or dexamethasone may be a promising therapy for adriamycin- and dexamethasone-resistant MM.

Statins enhances antitumor effect of oxaliplatin in KRAS-mutated colorectal cancer cells and inhibits oxaliplatin-induced neuropathy

BACKGROUND

KRAS mutations are fraught with the progression of colorectal cancer and resistance to chemotherapy. There are pathways such as extracellular regulated protein kinase 1/2 (ERK1/2) and Akt downstream and farnesylation and geranylgeranylation upstream that are activated upon mutated KRAS. Previous studies have shown that statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are effective to treat KRAS mutated colorectal cancer cells. Increased doses of oxaliplatin (L-OHP), a well-known alkylating chemotherapeutic drug, causes side effects such as peripheral neuropathy due to ERK1/2 activation in spinal cords. Hence, we examined the combinatorial therapeutic efficacy of statins and L-OHP to reduce colorectal cancer cell growth and abrogate neuropathy in mice.

METHODS

Cell survival and confirmed apoptosis was assessed using WST-8 assay and Annexin V detection kit. Detection of phosphorylated and total proteins was analyzed the western blotting. Combined effect of simvastatin and L-OHP was examined the allograft mouse model and L-OHP-induced neuropathy was assessed using cold plate and von Frey filament test.

RESULTS

In this study, we examined the effect of combining statins with L-OHP on induction of cell death in colorectal cancer cell lines and improvement of L-OHP-induced neuropathy in vivo. We demonstrated that combined administration with statins and L-OHP significantly induced apoptosis and elevated the sensitivity of KRAS-mutated colorectal cancer cells to L-OHP. In addition, simvastatin suppressed KRAS prenylation, thereby enhancing antitumor effect of L-OHP through downregulation of survivin, XIAP, Bcl-xL, and Bcl-2, and upregulation of p53 and PUMA via inhibition of nuclear factor of κB (NF-κB) and Akt activation, and induction of c-Jun N-terminal kinase (JNK) activation in KRAS-mutated colorectal cancer cells. Moreover, simvastatin enhanced the antitumor effects of L-OHP and suppressed L-OHP-induced neuropathy via ERK1/2 activation in vivo.

CONCLUSION

Therefore, statins may be therapeutically useful as adjuvants to L-OHP in KRAS-mutated colorectal cancer and may also be useful in the treatment of L-OHP-induced neuropathy.

Hypoxia-inducible factor 1α inhibitor induces cell death via suppression of BCR-ABL1 and Met expression in BCR-ABL1 tyrosine kinase inhibitor sensitive and resistant chronic myeloid leukemia cells

Chronic myeloid leukemia (CML) has a markedly improved prognosis with the use of breakpoint cluster region-abelson 1 (BCR-ABL1) tyrosine kinase inhibitors (BCR-ABL1 TKIs). However, approximately 40% of patients are resistant or intolerant to BCR-ABL1 TKIs. Hypoxia-inducible factor 1α (HIF-1α) is a hypoxia response factor that has been reported to be highly expressed in CML patients, making it a therapeutic target for BCR-ABL1 TKI-sensitive CML and BCR-ABL1 TKI-resistant CML. In this study, we examined whether HIF-1α inhibitors induce cell death in CML cells and BCR-ABL1 TKI-resistant CML cells. We found that echinomycin and PX-478 induced cell death in BCR-ABL1 TKIs sensitive and resistant CML cells at similar concentrations while the cell sensitivity was not affected with imatinib or dasatinib in BCR-ABL1 TKIs resistant CML cells. In addition, echinomycin and PX-478 inhibited the c-Jun N-terminal kinase (JNK), Akt, and extracellular-regulated protein kinase 1/2 (ERK1/2) activation via suppression of BCR-ABL1 and Met expression in BCR-ABL1 sensitive and resistant CML cells. Moreover, treatment with HIF-1α siRNA induced cell death by inhibiting BCR-ABL1 and Met expression and activation of JNK, Akt, and ERK1/2 in BCR-ABL1 TKIs sensitive and resistant CML cells. These results indicated that HIF-1α regulates BCR-ABL and Met expression and is involved in cell survival in CML cells, suggesting that HIF-1α inhibitors induce cell death in BCR-ABL1 TKIs sensitive and resistant CML cells and therefore HIF-1α inhibitors are potential candidates for CML treatment. [BMB Reports 2023; 56(2): 78-83].

Activation of ERK1/2 by MOS and TPL2 leads to dasatinib resistance in chronic myeloid leukaemia cells

The development of BCR::ABL1 tyrosine kinase inhibitors (TKIs), such as dasatinib, has dramatically improved survival in cases of chronic myeloid leukaemia (CML). However, the development of resistance to BCR::ABL1 TKIs is a clinical problem. BCR::ABL1 TKI resistance is known to have BCR::ABL1-dependent or BCR::ABL1-independent mechanisms, but the mechanism of BCR::ABL1 independence is not well understood. In the present study, we investigated the mechanism of BCR::ABL1-independent dasatinib resistance. The expression and activation level of genes or proteins were evaluated using array CGH, real time PCR, or western blot analysis. Gene expression was modulated using siRNA-mediated knockdown. Cell survival was assessed by using trypan blue dye method. We found that dasatinib-resistant K562/DR and KU812/DR cells did not harbour a BCR::ABL1 mutation but had elevated expression and/or activation of MOS, TPL2 and ERK1/2. In addition, MOS siRNA, TPL2 siRNA and trametinib resensitized dasatinib-resistant cells to dasatinib. Moreover, expression levels of MOS in dasatinib non-responder patients with CML were higher than those in dasatinib responders, and the expression of TPL2 tended to increase in dasatinib non-responder patients compared with that in responder patients. Our results indicate that activation of ERK1/2 by elevated MOS and TPL2 expression is involved in dasatinib resistance, and inhibition of these proteins overcomes dasatinib resistance. Therefore, MOS, TPL2 and ERK1/2 inhibitors may be therapeutically useful for treating BCR::ABL1-independent dasatinib-resistant CML.

Hypoxia-inducible factor 1α inhibitor induces cell death via suppression of BCR-ABL1 and Met expression in BCR-ABL1 tyrosine kinase inhibitor sensitive and resistant chronic myeloid leukemia cells

Chronic myeloid leukemia (CML) has a markedly improved prognosis with the use of breakpoint cluster region-abelson 1 (BCR-ABL1) tyrosine kinase inhibitors (BCR-ABL1 TKIs). However, approximately 40% of patients are resistant or intolerant to BCR-ABL1 TKIs. Hypoxia-inducible factor 1α (HIF-1α) is a hypoxia response factor that has been reported to be highly expressed in CML patients, making it a therapeutic target for BCR-ABL1 TKI-sensitive CML and BCR-ABL1 TKI-resistant CML. In this study, we examined whether HIF-1α inhibitors induce cell death in CML cells and BCR-ABL1 TKI-resistant CML cells. We found that echinomycin and PX-478 induced cell death in BCR-ABL1 TKIs sensitive and resistant CML cells at similar concentrations while the cell sensitivity was not affected with imatinib or dasatinib in BCR-ABL1 TKIs resistant CML cells. In addition, echinomycin and PX-478 inhibited the c-Jun N-terminal kinase (JNK), Akt, and extracellular-regulated protein kinase 1/2 (ERK1/2) activation via suppression of BCR-ABL1 and Met expression in BCR-ABL1 sensitive and resistant CML cells. Moreover, treatment with HIF-1α siRNA induced cell death by inhibiting BCR-ABL1 and Met expression and activation of JNK, Akt, and ERK1/2 in BCR-ABL1 TKIs sensitive and resistant CML cells. These results indicated that HIF-1α regulates BCR-ABL and Met expression and is involved in cell survival in CML cells, suggesting that HIF-1α inhibitors induce cell death in BCR-ABL1 TKIs sensitive and resistant CML cells and therefore HIF-1α inhibitors are potential candidates for CML treatment. [BMB Reports 2023; 56(2): 78-83].

Organogermanium THGP Induces Differentiation into M1 Macrophages and Suppresses the Proliferation of Melanoma Cells via Phagocytosis

M1 macrophages are an important cell type related to tumor immunology and are known to phagocytose cancer cells. In previous studies, the organogermanium compound poly-trans-[(2-carboxyethyl)germasesquioxane] (Ge-132) and its hydrolysate, 3-(trihydroxygermyl) propanoic acid (THGP), have been reported to exert antitumor effects by activating NK cells and macrophages through the induction of IFN-γ activity in vivo. However, the detailed molecular mechanism has not been clarified. In this study, we found that macrophages differentiate into the M1 phenotype via NF-κB activation under long-term culture in the presence of THGP in vitro and in vivo. Furthermore, long-term culture with THGP increases the ability of RAW 264.7 cells to suppress B16 4A5 melanoma cell proliferation. These mechanisms indicate that THGP promotes the M1 polarization of macrophages and suppresses the expression of signal-regulatory protein alpha (SIRP-α) in macrophages and CD47 in cancers. Based on these results, THGP may be considered a new regulatory reagent that suppresses tumor immunity.

Seeking Repeating Anthropogenic Seismic Sources: Implications for Seismic Velocity Monitoring at Fault Zones

Seismic velocities in rocks are highly sensitive to changes in permanent deformation and fluid content. The temporal variation of seismic velocity during the preparation phase of earthquakes has been well documented in laboratories but rarely observed in nature. It has been recently found that some anthropogenic, high-frequency (>1 Hz) seismic sources are powerful enough to generate body waves that travel down to a few kilometers and can be used to monitor fault zones at seismogenic depth. Anthropogenic seismic sources typically have fixed spatial distribution and provide new perspectives for velocity monitoring. In this work, we propose a systematic workflow to seek such powerful seismic sources in a rapid and straightforward manner. We tackle the problem from a statistical point of view, considering that persistent, powerful seismic sources yield highly coherent correlation functions (CFs) between pairs of seismic sensors. The algorithm is tested in California and Japan. Multiple sites close to fault zones show high-frequency CFs stable for an extended period of time. These findings have great potential for monitoring fault zones, including the San Jacinto Fault and the Ridgecrest area in Southern California, Napa in Northern California, and faults in central Japan. However, extra steps, such as beamforming or polarization analysis, are required to determine the dominant seismic sources and study the source characteristics, which are crucial to interpreting the velocity monitoring results. Train tremors identified by the present approach have been successfully used for seismic velocity monitoring of the San Jacinto Fault in previous studies.

Effects of group therapy on jumping to conclusion bias in adolescents with autism spectrum disorder : An exploratory study

BACKGROUND AND PURPOSE

Jumping to conclusion (JTC)-a cognitive bias in thinking processes-leads to drawing conclusions based on little information, and could be related to psychosis and paranoia. While it has recently been pointed out that it could accompany the autism spectrum disorder (ASD), no interventions targeting this bias in adolescents with ASD have been reported. Therefore, this exploratory study investigated the effects of a group social cognition program on JTC bias in adolescents with ASD.

PATIENTS AND METHODS

Group rehabilitation using social cognition and interaction training (SCIT) was conducted for 12- to 18-year-old adolescents with ASD. An SCIT program comprehensively targets social cognitive functions, including interventions for JTC bias, and examines changes before and after the SCIT intervention, social cognitive functioning tasks, and subjective quality of life (QOL).

RESULTS

Thirteen adolescents with ASD participated in this program ; 10 (76.9%) stayed through it. The proportion of participants with JTC bias decreased significantly before and after SCIT (before : 7/10 ; after : 1/10 ; p = 0.041), and subjective QOL increased significantly (p=0.014).

CONCLUSION

The results show that a group social cognition program with a JTC bias approach improves the JTC bias and increases subjective QOL in adolescents with ASD. J. Med. Invest. 70 : 115-122, February, 2023.

Who are hikikomori? Demographic and clinical features of hikikomori (prolonged social withdrawal): A systematic review

OBJECTIVE

This review, which was registered with PROSPERO (CRD42021237988), aimed to systematically extract common elements in the hikikomori definition or criteria applied by researchers and examine cultural differences and chronological changes in the demographic characteristics of hikikomori individuals such as age, gender and hikikomori duration.

METHOD

For inclusion in the review, the hikikomori criteria, age and gender of the hikikomori individuals had to be specified, and the article had to be peer-reviewed and written in Japanese or English, focusing on hikikomori individuals or their families. Case studies, reviews and qualitative studies were excluded.

RESULTS

The total sample size for the 52 studies included in the review was 4744. Over 80% of the studies included the elements 'not working or attending school', 'not socializing outside one's home' and 'duration of hikikomori' in their hikikomori criteria, and many studies included the element 'staying at home on most days except solitary outings'. A cross-temporal meta-analysis showed the possibility that the age of hikikomori individuals increased chronologically (β = 0.44, B = 0.50, 95% confidence interval = [0.16, 0.84]). Comparisons weighted by sample size between Japan and other countries showed the possibility that the age of hikikomori individuals was higher (d = 0.32), the percentage of males was lower (d = 0.91) and the hikikomori duration was shorter (d = 2.06) in studies conducted in countries other than Japan. However, many of the included studies had a high risk of selection bias, and this bias may have influenced the results obtained. Thus, the results of this study may represent the researcher's perception of hikikomori rather than accurately representing the actual condition of hikikomori.

CONCLUSION

Researchers should specifically identify similarities and differences in the clinical picture of hikikomori and compare the studies to organize the findings derived from studies focusing on hikikomori.

The Organogermanium Compound 3-(Trihydroxygermyl) Propanoic Acid (THGP) Suppresses Inflammasome Activation Via Complexation with ATP

Inflammasome activity is a key indicator of inflammation. The inflammasome is activated by pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), which activate the p38-NF-κB pathway and promote IL-1β transcription (signaling step 1). Next, extracellular adenosine triphosphate (ATP) activates the inflammasome (a protein complex consisting of a signal recognition protein, an adapter protein, and Caspase-1) and secretion of inflammatory cytokines such as IL-1β (signaling step 2). Inflammasome activation causes excessive inflammation, leading to inflammasome-active diseases such as atherosclerosis and type 2 diabetes. A hydrolysate of the organogermanium compound Ge-132, 3-(Trihydroxygermyl) propanoic acid (THGP) can form a complex with a cis-diol structure. We investigated the inhibitory effect of THGP on inflammasome activity in human THP-1 monocytes. THGP inhibited IL-1β secretion and caspase-1 activation (signaling step 2) in an ATP-dependent manner. On the other hand, THGP did not suppress IL-1β secretion induced by only lipopolysaccharide (LPS) stimulation. In addition, as IL-6 is an ATP-independent inflammatory cytokine, THGP did not decrease its secretion. THGP also suppressed pyroptosis, which is a caspase-1 activity-dependent form of cell death. Therefore, THGP is expected to become a new therapeutic or prophylactic agent for inflammasome-associated diseases.

Pioglitazone-incorporated microspheres alleviates cardiac dysfunction through macrophage polarization in a rat myocardial infarction model

 

Inflammatory processes are essential for the repair processes after myocardial infarction. Among inflammatory cells involved in this process, macrophages play a critical role through polarization in pro-inflammatory M1 or reparative M2 subtype. Pioglitazone, known as a treatment drug for diabetes mellitus, is reported to regulate macrophage polarization toward reparative M2 subtype. Poly L-lactic-co-glycolic acid (PLGA) has been widely accepted as the delivery carrier in drug delivery system (DDS).

Here, we aimed to validate the therapeutic effects and investigate the mechanisms of DDS-based treatment using pioglitazone to left ventricular remodeling after myocardial infarction.

Pioglitazone-incorporated PLGA microspheres (PGZ-MS) were prepared and the drug release profile was evaluated. The concentration of interleukin-10 secreted from murine bone marrow derived macrophages incubated with PGZ-MS was quantified in the culture supernatant. To validate the therapeutic potential of PGZ-MS in vivo, Sprague-Dawley rats were subjected to permanent left coronary artery ligation to induce myocardial infarction. Mock-MS (100 μg) or PGZ-MS (100 μg) was injected to the infarct region just after induction (n=9–11/group). Cardiac function and left ventricular size were assessed by echocardiography. At 28-day after surgery, rats were sacrificed, and excised hearts were evaluated histologically.

PGZ-MS released 1.8±0.3% of incorporated PGZ within 24 hours and 29.5±1.2% within 14 days indicating sustained release of PGZ in vitro. PGZ-MS augmented Interleukin-10 release from bone marrow derived macrophages, indicating polarization toward reparative M2 subtype. PGZ-MS significantly ameliorated cardiac function after myocardial infarction (fractional shortening: MI vs MI+Mock-MS vs MI+PGZ-MS, 24.4±1.1 vs 24.3±1.6 vs 32.2±1.4%; P=0.0035) with reverse remodeling (wall thickness: MI vs MI+Mock-MS vs MI+PGZ-MS, 0.69±0.12 vs 0.71±0.13 vs 1.06±0.09; P=0.03). Immunohistochemical analyses revealed that PGZ-MS enhanced macrophage polarization toward reparative M2 subtype (ratio of reparative M2 macrophages: 0.39±0.03 vs 0.42±0.02 vs 0.54±0.02; P=0.0004) and attenuated apoptosis of cardiomyocytes in the ischemic border zone (MI vs MI+Mock-MS vs MI+PGZ-MS, 2.6±0.2 vs 1.9±0.2 vs 1.2±0.2 cells/field; P=0.002).

In the present study, we confirmed that PGZ-MS could realize sustained release of pioglitazone which resulted in sustained effect of macrophage polarization and attenuated left ventricular remodeling accompanied with the amelioration of cardiac dysfunction and cardiomyocytes apoptosis. The strategy of DDS-based macrophage polarization might serve as a promising strategy in cardiac regenerative therapy for ischemic heart disease in the future.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grants-in-Aid for Scientific Research from the Ministry of Education, Science, Sports and Culture of Japan

Structure of χ3-Borophene Studied by Total-Reflection High-Energy Positron Diffraction (TRHEPD)

We have investigated the structure of χ₃-borophene on Ag(111), a monolayer material of boron atoms, via total-reflection high-energy positron diffraction (TRHEPD). By comparing the experimental rocking-curves with ones for several structures calculated by using dynamical diffraction theory, we confirmed that the χ₃-borophene layer has a flat structure. The distance from the topmost layer of the metal crystal is 2.4 Å, which is consistent with results reported by X-ray standing wave-excited X-ray photoelectron spectroscopy. We also demonstrated that the in-plane structure of χ₃-borophene is compatible with the theoretical predictions. These structural properties indicate that χ₃-borophene belongs to a group of epitaxial monolayer sheets, such as graphene, which have weak interactions with the substrates.

[Administration Period of Olanzapine as an Antiemetic Drug for Patients on FEC Therapy-A Survey]

Olanzapine(OLZ)is a multi-acting receptor-targeted antipsychotic drug approved in Japan in December 2017 for the treatment of anticancer drug-induced nausea and vomiting. However, the recommended doses and administration periods of OLZ in the literature and guidelines are varied. Reports on the efficacy and safety of OLZ combined with perioperative chemotherapy for breast cancer in Japanese patients are few. Moreover, the risk of nausea and vomiting during treatment with anticancer drugs in young and women patients remains to be high. In this study, we conducted an exploratory survey on the optimal duration of OLZ administration(days 1-4: 5 mg, before sleep)during perioperative breast cancer 5-fluorouracil, epirubicin, cyclophosphamide(FEC)therapy. We found that treatment with OLZ showed efficacy in improving nausea grade and maintaining relative dose intensity. Moreover, it could be used safely without interruption due to side effects, such as weight gain, elevation in blood glucose, somnolence, and insomnia. Prophylactic antiemetic therapy with OLZ administration (days 1-4: 5 mg)prior to sleep was effective in patients having FEC therapy-induced nausea and vomiting.

Endoscopic modified transseptal bi-nostril approach for pituitary tumors. Efficacy of complex preservation of every turbinate and olfaction: A STROBE analysis

AIMS

Endoscopic modified transseptal bi-nostril approach minimizes turbinate and olfactory mucosal invasion and ensures preservation of the turbinates and bilateral olfaction. The main objective of this study was to investigate the pre- and postoperative variations in olfactory function in patients using this approach, and the secondary objective was to investigate the complications associated with the surgical procedure.

MATERIAL AND METHODS

This study is a single-center prospective cohort study using STROBE analysis. To completely protect the bilateral turbinates and olfactory epithelium, this procedure provided access to the sphenoid sinus by a transseptal approach via the left nasal cavity and by the olfactory cleft approach via the right nasal cavity without any turbinate resection. A T&T olfactometer was used to assess the mean recognition threshold of the left, right, and bilateral nasal passages before and after surgery, and complications associated with the surgical approach were investigated.

OBJECTIVES

We included 27 patients who underwent endoscopic modified transseptal pituitary surgery with an olfactory and turbinate preservation approach at our hospital between April 2018 and December 2019.

RESULTS

The mean postoperative recognition threshold of the right, left, and bilateral nasal cavities did not worsen (P<0.001 for all) relative to the preoperative values, and there was no difference in values between the right and left nasal cavities (P=0.85). The nasal turbinates were preserved in all patients during the study period, and no recurrence was observed.

CONCLUSION

Our modified EETSA could be implemented as an approach for turbinate and olfaction preservation.

EGFR inhibition reverses epithelial‑mesenchymal transition, and decreases tamoxifen resistance via Snail and Twist downregulation in breast cancer cells

Tamoxifen resistance remains a major obstacle in the treatment of estrogen receptor (ER)‑positive breast cancer. In recent years, the crucial role of the epithelial‑mesenchymal transition (EMT) process in the development of drug resistance in breast cancer has been underlined. However, the central molecules inducing the EMT process during the development of tamoxifen resistance remain to be elucidated. In the present study, it was demonstrated that tamoxifen‑resistant breast cancer cells underwent EMT and exhibited an enhanced cell motility and invasive behavior. The inhibition of snail family transcriptional repressor 1 (Snail) and twist family BHLH transcription factor 1 (Twist) reversed the EMT phenotype and decreased the tamoxifen resistance, migration and invasion of tamoxifen‑resistant breast cancer cells. In addition, it was observed that the inhibition of epidermal growth factor receptor (EGFR) reversed the EMT phenotype in tamoxifen‑resistant MCF7 (MCF‑7/TR) cells via the downregulation of Snail and Twist. Notably, the EGFR inhibitor, gefitinib, decreased tamoxifen resistance, migration and invasion through the inhibition of Snail and Twist. On the whole, the results of the present study suggest that EGFR may be a promising therapeutic target for tamoxifen‑resistant breast cancer. Moreover, it was suggested that gefitinib may serve as a potent novel therapeutic strategy for breast cancer patients, who have developed tamoxifen resistance.

Experimental study on natural convection in the vertical enclosure of a double coaxial cylinder

This paper presents results of an experimental study on natural convection in the vertical enclosure of a double coaxial cylinder where the inner wall is at constant heat flux. It is the objective of this experiment to understand the basic characteristics of heat transfer under the condition of natural convection coupled with thermal radiation in a vertical enclosure. The range of Rayleigh numbers based on the width of the double coaxial cylinder is set to be 5.6 × 105 < Ra < 1.04 × 108, the radius ratio is 2.73, the aspect ratio is 3.43 (cylinder length divided by annular gap). The heat transfer coefficient of natural convection coupled with thermal radiation was obtained as function of the Rayleigh number, aspect ratio of the enclosure, and temperature of the hot and cold surfaces. The experimental results show that thermal radiation can’t be neglected in analyzing heat transfer of vertical annulus with natural convection. The results provide the basic data for the design and the performance assessment of the future passive cooling system used in a high-temperature engineering test reactor.

Combination treatment with statins and bezafibrate induces myotoxicity via inhibition of geranylgeranyl pyrophosphate biosynthesis and Rho activation in L6 myoblasts and myotube cells

Statins and fibrates are frequently used to treat hyperlipidemia; however, these drugs may have adverse effects such as rhabdomyolysis. The incidence of rhabdomyolysis due to fibrates and statins is low (0.0028-0.0096%) when administered as monotherapy, however it increases to 0.015-0.021% when the drugs are used in combination. The mechanism underlying myotoxicity induced by the combination of statins and fibrates is yet unclear. Here, we investigated the mechanisms underlying induced myotoxicity in rat myoblasts L6 and differentiated L6 cells (myotubes) using a combination of statins and fibrates. We found that cell death induced by a combination of fluvastatin or simvastatin with bezafibrate or fenofibrate in L6 myoblasts and myotubes was mediated by inhibition of geranylgeranyl pyrophosphate (GGPP) production. Additionally, the drug combination inhibited Rho activation in L6 myoblasts and myotube cells. In L6 myoblasts, the combination of statins and bezafibrate enhanced p27 expression and induced G1 arrest and apoptosis. Furthermore, combined treatment suppressed Akt activation and enhanced Bim expression in L6 myotubes but did not affect extracellular regulated protein kinase 1/2 activation. These results suggested that combined administration of statins and fibrates induced death of L6 myoblasts and myotube cells by inhibiting GGPP biosynthesis and Rho pathway activation. Supplementation with GGPP may be therapeutically beneficial for preventing myotoxicity associated with combined statin and fibrates treatment.

Sorafenib treatment of metastatic melanoma with c-Kit aberration reduces tumor growth and promotes survival

Melanomas are highly malignant tumors that readily metastasize and have poor prognosis. Targeted therapy is a cornerstone of treatment for patients with melanoma. Although c-Kit gene aberration has found in 5-10% of melanoma cases, research on c-Kit inhibitors for melanoma with c-Kit aberration have been disappointing. Sorafenib is a tyrosine kinase inhibitor, whose targets include c-Kit, platelet derived growth factor receptor (PDGFR), VEGFR and RAF. The present study aimed to examine the effect of sorafenib on metastatic melanoma with c-Kit aberration. Cell viability was assessed via trypan blue assay. Migration and invasion were analyzed using cell culture inserts. The anti-metastatic effects and antitumour activity of sorafenib were determined in an in vivo model. Protein expression was detected via western blotting, and the expression of MMP and very late antigen (VLA) was detected via reverse transcription-quantitative PCR. It was identified that sorafenib decreased cell viability, migration and invasion in vitro. Furthermore, sorafenib inhibited metastasis and tumor growth in vivo. Mechanistically, sorafenib inhibited c-Kit, PDGFR, VEGFR, B-Raf and c-Raf phosphorylation both in vitro and in vivo. In addition, sorafenib reduced the expression levels of MMPs and VLA. Importantly, there was a significant effect of sorafenib treatment on overall survival in mice. Collectively, this study suggests that sorafenib may serve as a novel therapeutic option for melanoma with c-Kit dysregulation.

Objective evaluation of nutritional status using the prognostic nutritional index during and after chemoradiotherapy in Japanese patients with head and neck cancer: a retrospective study

OBJECTIVES

The incidence of severe mucosal damage due to low nutritional status is high in patients receiving concurrent chemoradiotherapy (CCRT) for head and neck cancer. Objective assessments do not exist for discharge criteria after completion of CCRT. Although the prognostic nutritional index (PNI) is an objective indicator of postoperative outcomes in patients undergoing cancer surgery, the prognostic impact of the PNI in patients with head and neck cancer receiving CCRT is unexplored. We investigated whether the PNI could be an objective criterion for nutritional status and a discharge criterion after completion of CCRT.

METHODS

We assessed the medical records of 23 patients with head and neck cancer who received triweekly cisplatin +radiotherapy (2 Gy ×35 fractions). We evaluated whether the PNI could be a useful evaluation indicator in patients with head and neck cancer receiving CCRT and determined the cut-off PNI value by receiver operating characteristic (ROC) curve analysis as a criterion for hospital discharge.

RESULTS

The PNI pre-treatment and post-treatment values were 51.0 and 38.0, respectively (p<0.05). The median length of hospitalisation after therapy was 5 days in patients with grades 1 and 2 and 10 days in patients with grade 3 oral and pharyngeal mucositis (p<0.05). The optimal cut-off PNI value as a criterion for hospital discharge was found to be 40.4 (grades 1 and 2 mucositis) and 38.6 (grade 3 mucositis) by the ROC analysis.

CONCLUSIONS

The PNI is a simple, objective and temporal indicator which is useful in assessing the nutritional status of patients with head and neck cancer. The PNI could be used as an objective indicator to determine the time of discharge after CCRT completion.

Preemptive analgesia for endoscopic sinus surgery: a retrospective study

BACKGROUND

Chronic rhinosinusitis (CRS) is a common disease, and endoscopic sinus surgery (ESS) is widely performed. However, there is no consensus regarding postoperative pain control after ESS, and postoperative opioid abuse is a problem in many countries. Acetaminophen is reportedly effective for postoperative pain control. Preemptive analgesia has received more attention lately, wherein pain is prevented before it occurs. In this study, we assessed the use of acetaminophen for preemptive analgesia during the perioperative period in ESS.

METHODOLOGY

This is a retrospective study of 175 patients who underwent ESS, septoplasty, and bilateral inferior turbinate mucosal resection at our hospital from April 2016 to February 2018. In total, 82 patients received 1,000 mg of acetaminophen during surgery and 4 hours after the first dose, while 93 patients did not receive it routinely. We compared these two groups. The primary outcome was the need to use additional analgesics prescribed by the ward physician and the secondary outcomes included postoperative pain, postoperative bleeding, reoperation, blood pressure, and body temperature.

RESULTS

The use of additional oral and intravenous analgesics was significantly reduced in the patients who received acetaminophen perioperatively.

CONCLUSION

Preemptive analgesia during the perioperative period of ESS could lead to satisfactory postoperative pain control.

Potentially harmful excipients in neonatal medications: a multicenter nationwide observational study in Japan

Background

A multicenter investigation of neonate exposure to potentially harmful excipients (PHEs) in neonatal intensive care units (NICUs) in Japan has not been conducted.

Methods

A multicenter nationwide observational study was conducted. Neonate patient demographic data and information on all medicines prescribed and administered during hospitalization on 1 day between November 2019 and March 2021 were extracted from the medical records. Nine PHEs, paraben, polysorbate 80, propylene glycol, benzoates, saccharin sodium, sorbitol, ethanol, benzalkonium chloride, and aspartame, were selected. PHEs were identified from the package insert and the Interview Form. The quantitative daily exposure was calculated if quantitative data were available for each product containing the PHE.

Results

Prescription data was collected from 22 NICUs in Japan. In total, 343 neonates received 2360 prescriptions for 426 products containing 228 active pharmaceutical ingredients. PHEs were found in 52 (12.2%) products in 646 (27.4%) prescriptions for 282 (82.2%) neonates. Benzyl alcohol, sodium benzoates, and parabens were the most common PHEs in parenteral, enteral, and topical formulations, respectively. Quantitative analysis showed that 10 (10%), 38 (42.2%), 37 (94.9%), and 9 (39.1%) neonates received doses exceeding the acceptable daily intake of benzyl alcohol, polysorbate 80, propylene glycol, and sorbitol, respectively. However, due to the lack of quantitative information for all enteral and topical products, accurate daily PHE exposure could not be quantified.

Conclusions

Neonates admitted to NICUs in Japan were exposed to PHEs, and several of the most commonly prescribed medicines in daily clinical practice in NICUs contained PHEs. Neonate PHE exposure could be reduced by replacing these medicines with available PHE-free alternatives.

Inhibition of yes-associated protein suppresses migration, invasion, and metastasis in non-small cell lung cancer in vitro and in vivo

Non-small cell lung cancer (NSCLC) is a highly aggressive cancer with one of the most prevalent malignant tumors. Metastasis in NSCLC is the major cause of treatment failure and cancer-related deaths. Yes-associated protein (YAP) is a transcriptional coactivator regulated by the evolutionarily conserved Hippo signaling pathway that regulates organ size, growth, and regeneration. YAP is highly expressed in several malignant tumor types. Furthermore, YAP promotes tumor initiation and/or progression in various types of cancer. However, it is unclear whether YAP contributes to the metastasis in NSCLC and serves as a useful therapeutic target. Here, we investigated whether levels of YAP correlate with metastatic phenotype in NSCLC cells and serve as a useful therapeutic target. We found that high levels of YAP associate with high cell migration, invasion, and metastasis in NSCLC cell lines. Furthermore, YAP siRNA decreased the migration and invasion in NSCLC cells. Additionally, verteporfin, an agent used for the treatment of symptomatic polypoidal choroidal vasculopathy, decreased the expression of YAP and inhibited migration, invasion, and metastasis in NSCLC cells. Thus, the study suggests that targeting YAP may present a new avenue to develop therapeutics against metastasis in NSCLC and that verteporfin has potential molecular therapeutic strategy for the treatment of metastatic NSCLC.

Interleukin 19 suppresses RANKL-induced osteoclastogenesis via the inhibition of NF-κB and p38MAPK activation and c-Fos expression in RAW264.7 cells

Interleukin 19 (IL-19) is a member of the IL-10 family of cytokines and is known as an inhibitory cytokine. IL-10, also an inhibitory cytokine, suppresses the receptor activator of nuclear factor κB (NF-κB) ligand (RANKL)-induced osteoclast differentiation. However, the effects of IL-19 on osteoclast differentiation are not currently well-understood. In this study, we examined whether IL-19 suppresses osteoclast differentiation in the mouse macrophage-like cell line RAW264.7. We found that IL-19 inhibited RANKL-induced osteoclast differentiation. In addition, IL-19 suppressed RANKL-induced NF-κB and p38 mitogen-activated protein kinase (p38MAPK) activation and c-Fos expression. Moreover, RANKL inhibited IL-19 mRNA expression and secretion in RAW264.7 cells, and the inhibition of the IL-19 function promoted osteoclast differentiation. These results indicate that IL-19 suppressed osteoclast differentiation via the inhibition of NF-κB and p38MAPK activation and c-Fos expression. Furthermore, IL-19 may maintain the osteoclast precursor state, such as monocytes and macrophages. These findings may be useful in the development of osteoclast inhibitors, thereby improving treatments for osteoclast activation-related diseases, such as osteoporosis.

Perifosine enhances the potential antitumor effect of 5-fluorourasil and oxaliplatin in colon cancer cells harboring the PIK3CA mutation

Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutation in colon cancer contributes to the poor prognosis of the disease and chemoresistance of tumors. New therapies are needed; however, the lack of knowledge of the mechanism of chemoresistance has hindered progress. In this study, we investigated the mechanism of the reduced sensitivity of colon cancer cells to 5-fluorouracil (5-FU) and oxaliplatin (L-OHP), and the effects of perifosine, an Akt inhibitor that enhances the cytotoxicity of 5-FU and L-OHP in colon cancer cells harboring the PIK3CA mutation. The use of 5-FU or L-OHP alone or in combination induced significant death of Caco-2 cells (PIK3CA wild type), but only weakly decreased the viability of DLD-1 and SW948 cells harboring the PIK3CA mutation. The use of 5-FU and L-OHP, either alone or in combination, strongly suppressed Akt activation, Survivin, Bcl-2, and Bcl-xL expression, and enhanced Puma, phospho-p53, and p53 expression in Caco-2 cells than in DLD-1 cells. In addition, perifosine enhanced the cytotoxicity of the 5-FU and L-OHP combination, inhibited Akt activation and the expression of Survivin, Bcl-2, and Bcl-xL, and increased the expression of Puma, phospho-p53, and p53 in DLD-1 cells. These results indicate that PIK3CA mutation contributes to reduced sensitivity to 5-FU and L-OHP via Akt activation in colon cancer cells. Perifosine increases the efficacy of 5-FU and L-OHP by suppressing Akt activation. Thus, the use of an Akt inhibitor in combination with 5-FU and L-OHP may be beneficial in colon cancer with cells harboring the PIK3CA mutation.

FTI-277 and GGTI-289 induce apoptosis via inhibition of the Ras/ERK and Ras/mTOR pathway in head and neck carcinoma HEp-2 and HSC-3 cells

PURPOSE

Head and neck squamous cell carcinoma (HNSCC) is a major malignancy worldwide. Ras overexpression in HNSCC is known to promote tumor cell growth; therefore, inhibition of Ras activation could lead to tumor growth suppression in HNSCC patients. Here, we investigated the effect of FTI-277, a farnesyl transferase inhibitor, and GGTI-287, a geranyltransferase 1 inhibitor, on the Ras signaling pathway in HNSCC cell lines-HEp-2 and HSC-3.

METHODS

Cell viability was analyzed using the trypan blue staining exclusion assay. The apoptosis of cells was assessed by flow cytometry and caspase activation analysis. The expression levels of proteins were examined using western blot analysis.

RESULTS

FTI-277 and GGTI-287 induced cell death, enhanced caspase 3 activity, and increased the number of annexin V-positive cells in HEp-2 and HSC-3 cells. FTI-277 and GGTI-287 induced apoptosis in HSC-3 cells at much lower concentrations than that in HEp-2 cells. FTI-277 and GGTI-287 decreased the concentration of phosphorylated ERK1/2 and mTOR via membrane localization of Ras and enhanced Bim expression. Furthermore, FTI-277 and GGTI-287 induced cell death in v-H-Ras-transfected NIH3T3 (NW7) cells and not in empty vector-transfected NIH3T3 (NV20) cells.

CONCLUSION

FTI-277 and GGTI-287 may be useful as potential therapeutic agents for treating HNSCC patients; moreover, farnesyl transferase and geranylgeranyltransferase 1 inhibitors can be further developed as anticancer agents.

Observation of Coulomb-Assisted Nuclear Bound State of Ξ^{-}-^{14}N System

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21  MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

Partition Efficiency of Eccentric Coil for Countercurrent Chromatographic Separation of Proteins Using Small-scale Cross-axis Coil Planet Centrifuge with Circular and Elliptic Cylindrical Columns

The partition efficiency of the double-spaced coil for eccentric and toroidal coils on countercurrent chromatographic separation of proteins was evaluated using the small-scale cross-axis coil planet centrifuge (CPC) equipped with circular and elliptic cylindrical columns. Standard cytochrome c, myoglobin and lysozyme samples were used for separation with the 12.5% (w/w) polyethylene glycol 1000 and 12.5% (w/w) dibasic potassium phosphate system. In the circular column, the double-spaced eccentric coil yielded better peak resolution than the double-spaced toroidal coil, and the double-spaced eccentric coil yielded better peak resolution than the single-spaced eccentric coil. In the elliptic column, the double-spaced eccentric coil also produced better peak resolution than the double-spaced toroidal coil, but the single-spaced eccentric coil yielded better peak resolution than the double-spaced eccentric coil. The overall results indicated that the double-spaced eccentric coil for the circular column and the single-spaced eccentric coil for the elliptic column yielded better protein separation using the small-scale cross-axis CPC with aqueous two-phase solvent systems.

Rhosin Suppressed Tumor Cell Metastasis through Inhibition of Rho/YAP Pathway and Expression of RHAMM and CXCR4 in Melanoma and Breast Cancer Cells

The high mortality rate of cancer is strongly correlated with the development of distant metastases at secondary sites. Although Rho GTPases, such as RhoA, RhoB, RhoC, and RhoE, promote tumor metastasis, the main roles of Rho GTPases remain unidentified. It is also unclear whether rhosin, a Rho inhibitor, acts by suppressing metastasis by a downstream inhibition of Rho. In this study, we investigated this mechanism of metastasis in highly metastatic melanoma and breast cancer cells, and the mechanism of inhibition of metastasis by rhosin. We found that rhosin suppressed the RhoA and RhoC activation, the nuclear localization of YAP, but did not affect ERK1/2, Akt, or NF-κB activation in the highly metastatic cell lines B16BL6 and 4T1. High expression of YAP was associated with poor overall and recurrence-free survival in patients with breast cancer or melanoma. Treatment with rhosin inhibited lung metastasis in vivo. Moreover, rhosin inhibited tumor cell adhesion to the extracellular matrix via suppression of RHAMM expression, and inhibited SDF-1-induced cell migration and invasion by decreasing CXCR4 expression in B16BL6 and 4T1 cells. These results suggest that the inhibition of RhoA/C-YAP pathway by rhosin could be an extremely useful therapeutic approach in patients with melanoma and breast cancer.

Institutionalising wastewater surveillance systems to minimise the impact of COVID-19: cases of Indonesia, Japan and Viet Nam

This mini review describes the current status and challenges regarding institutionalisation of wastewater surveillance systems against COVID-19. Monitoring SARS-CoV-2 in wastewater has been proposed to be a potential tool to understand the actual prevalence of COVID-19 in the community, and it could be an effective approach to monitor the trend during the COVID-19 pandemic. However, challenges to institutionalise wastewater surveillance systems are still abundant and unfolding at a rapid rate given that the international understanding regarding the scientific knowledge and socio-political impacts of COVID-19 are in the developing stages. To better understand the existing challenges and bottlenecks, a comparative study between Japan, Viet Nam, and Indonesia was carried out in the present study. Through gaining a better understanding of common issues as well as issues specific to each country, we hope to contribute to building a robust multistakeholder system to monitor SARS-CoV-2 in wastewater as an effective disease surveillance system for COVID-19.

Governance of wastewater surveillance systems to minimize the impact of COVID-19 and future epidemics:Cases across Asia-Pacific

This chapter describes the current status and challenges regarding the governance of wastewater surveillance systems against COVID-19. Monitoring SARS-CoV-2 in wastewater has been proposed to be a potential tool to understand the actual prevalence of COVID-19 in the community, and it could be an effective tool during the pandemic to monitor the trend as well as beyond the pandemic as an early warning system to prevent future outbreaks. However, challenges to institutionalize wastewater surveillance systems are still abundant and unfolding at a rapid rate given that the international understanding regarding the scientific knowledge and socio-political impacts of COVID-19 are in the developing stages. To better understand the existing challenges and bottlenecks, a comparative study between eight countries across the Asia-Pacific was carried out. Through gaining a better understanding of common issues as well as issues specific to each country, we hope to contribute to building a robust multistakeholder system to monitor SARS-CoV-2 as well as future pathogens in wastewater as an effective disease surveillance system for COVID-19 and unknown epidemics (disease X) in the community level.

CD49d and CD49e induce cell adhesion-mediated drug resistance through the nuclear factor-κB pathway in Burkitt lymphoma

Burkitt lymphoma (BL) is a highly aggressive form of non-Hodgkin's B-cell lymphoma. Currently, multi-agent chemotherapy regimens are being used to significantly improve cure rates and achieve complete remissions in BL patients. However, drug resistance can often occur within 6 months in BL patients, contributing to poor prognosis. Mounting evidence suggests that cell adhesion-mediated drug resistance (CAM-DR), caused by the interaction between the bone marrow microenvironment and tumour cells may play an important role in drug resistance to chemotherapy. However, the molecular mechanism underlying CAM-DR in BL has not been identified yet. In this study, we investigated the molecular mechanism responsible for CAM-DR in BL cells. We also examined the therapeutic targets of CAM-DR in BL cells and found CD49d and CD49e to be the important adhesion molecules involved. However, CD49a, CD49b, CD11a, CD29, CD18, and CD61 were not found to be associated with CAM-DR in BL cells. Furthermore, we clarified that CD49d- and CD49e-mediated CAM-DR could be attributed to an increase in the expression of B cell leukemia-xL (Bcl-xL) and survivin proteins, and a decrease in the expression of Bcl-2 associated X (Bax), Bcl-2 interacting mediator (Bim) and p53 upregulated modulator of apoptosis (PUMA) proteins via nuclear factor kappaB (NF-κB) activation. In addition, bortezomib was found to overcome CAM-DR in BL cells by inhibiting NF-κB. Thus, bortezomib may have potential clinical applications in the treatment of CD49d- and CD49e-mediated CAM-DR in BL patients.

The HGF/Met/NF-κB Pathway Regulates RANKL Expression in Osteoblasts and Bone Marrow Stromal Cells

Multiple myeloma (MM)-induced bone disease occurs through hyperactivation of osteoclasts by several factors secreted by MM cells. MM cell-secreted factors induce osteoclast differentiation and activation via direct and indirect actions including enhanced expression of receptor activator of nuclear factor κB ligand (RANKL) in osteoblasts and bone marrow stromal cells (BMSCs). Hepatocyte growth factor (HGF) is elevated in MM patients and is associated with MM-induced bone disease, although the mechanism by which HGF promotes bone disease remains unclear. In the present study, we demonstrated that HGF induces RANKL expression in osteoblasts and BMSCs, and investigated the mechanism of induction. We found that HGF and MM cell supernatants induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. In addition, HGF increased phosphorylation of Met and nuclear factor κB (NF-κB) in ST2 cells, MC3T3-E1 cells, or mouse BMSCs. Moreover, Met and NF-κB inhibitors suppressed HGF-induced RANKL expression in ST2 cells, MC3T3-E1 cells, and mouse BMSCs. These results indicated that HGF promotes RANKL expression in osteoblasts and BMSCs via the Met/NF-κB signaling pathway, and Met and NF-κB inhibitors suppressed HGF-induced RANKL expression. Our findings suggest that Met and NF-κB inhibitors are potentially useful in mitigating MM-induced bone disease in patients expressing high levels of HGF.

AT9283 exhibits antiproliferative effect on tyrosine kinase inhibitor‑sensitive and ‑resistant chronic myeloid leukemia cells by inhibition of Aurora A and Aurora B

Imatinib is the gold standard in the conventional treatment of chronic myeloid leukemia (CML). However, some patients become resistant to imatinib therapy. To overcome this resistance, second‑generation (dasatinib, nilotinib, and bosutinib) and third‑generation (ponatinib) tyrosine kinase inhibitors (TKIs) have been developed and have been shown to be effective against refractory CML. Although these TKIs provide many benefits for patients with CML, advanced patients show resistance even to these TKIs. Therefore, novel therapeutic strategies are urgently needed for the treatment of TKI‑resistant CML patients. AT9283 is a multi‑targeted kinase inhibitor with potent activity against Janus kinase (JAK), Aurora kinases, and Abl. In the present study, we showed that AT9283 significantly decreased the cell viability of both TKI‑sensitive and TKI‑resistant CML cells as determined by trypan blue exclusion assay. In addition, cell cycle analysis, Annexin V assay, and caspase‑3/7 activity assay revealed that AT9283 increased the cell population in the G2/M phase and induced apoptosis. We investigated the molecular mechanisms underlying the decrease in cell viability upon treatment with AT9283 by western blotting. Interestingly, our results showed that AT9283 inhibited the expression of Aurora A, Aurora B, and downstream Histone H3 phosphorylation. In contrast, we observed no changes in the levels of Bcr‑Abl, signal transducer and activator of transcription 3 (STAT3), extracellular signal‑regulated kinase (ERK), and Akt phosphorylation. In addition, we found that AMG900, a selective Aurora A and Aurora B inhibitor, increased the G2/M phase cell population and induced apoptosis via inhibition of Aurora A and Aurora B in both TKI‑sensitive and TKI‑resistant CML cells. Our studies show that Aurora A and Aurora B are promising therapeutic targets for TKI‑sensitive and TKI‑resistant CML, and AT9283 may have potential clinical applications for the treatment of TKI‑resistant CML patients.

Dimethyl fumarate suppresses metastasis and growth of melanoma cells by inhibiting the nuclear translocation of NF-κB

BACKGROUND

Malignant melanoma is among the deadliest forms of skin cancers, and its incidence has been increasing over the past decades. In malignant melanoma, activation of the nuclear factor kappa B (NF-κB) promotes survival, migration, and invasion of cancer cells. Anti-NF-κB agents for treating metastatic melanoma would be beneficial, but no such drug is approved as either monotherapy or adjuvant therapy. Dimethyl fumarate (DMF) is an approved anti-inflammatory drug already in clinical use for psoriasis and multiple sclerosis.

OBJECTIVE

We investigated the anti-tumour effect of DMF treatment in metastatic melanoma in vitro and in vivo.

METHODS

The cell viability was assessed via trypan blue exclusion assay. The migration and invasion was analyzed in a Boyden chamber assay. The anti-metastatic effects and anti-tumour activity of DMF was determined in an in-vivo model. The expressions of NF-κB pathway and NF-κB regulatory proteins were detected via western blotting.

RESULTS

DMF decreased the cell viability, migration and invasion in vitro. In addition, DMF inhibited spontaneous metastasis and tumour growth. Mechanistically, DMF prevented the nuclear translocation of NF-κB, whereas no changes were observed in the phosphorylation levels of inhibitor of kappa B (IκB). In addition, DMF inhibited the expression of matrix metalloproteinases (MMPs) and very late antigens (VLAs). Furthermore, DMF treatment decreased the expression of Survivin and Bcl-extra large (Bcl-XL) proteins.

CONCLUSION

Our results suggest that DMF as a novel inhibitor of NF-κB may be a potential therapeutic agent for metastatic melanoma.