Inactivation of PTEN by post-translational modifications causes aberrant amplification of the PI3K/AKT signaling pathway in many tumors. PTEN is a tumor suppressor phosphatase that is frequently phosphorylated at conserved serine/threonine residues (S380, T382, and T383 clusters) in the C-terminal tail of ATL and various solid cancer cells. Here, we identify SCY1-like protein 2 (SCYL2), with a protein kinase-like domain, as a novel PTEN-binding protein; however, the mechanism by which SCYL2 regulates PTEN phosphorylation remains unclear. SCYL2-associated complex phosphorylates PTEN at STT, and SCYL2 downregulation has anti-tumor effects in ATL via inhibition of the PI3K/AKT signaling pathway by dephosphorylating PTEN at STT. SCYL2 reportedly binds to the clathrin heavy chain (CHC), which regulates cytoplasmic vesicle formation, trafficking, and signaling pathways. Our results indicate that SCYL2 expression induces the binding of CHC to PTEN. Furthermore, the inhibition of clathrin-coated vesicles (CCVs) by CHC downregulation or inhibition suppresses cell survival by reducing phosphorylated PTEN at the STT, suggesting that SCYL2 enhances PTEN phosphorylation through CCVs as a signaling platform. Our results indicate that SCYL2/CHC complex plays a pivotal role in regulating the PI3K/AKT signaling pathway through PTEN phosphorylation, thus leading to tumor development and may be a promising novel target for treating tumors.

Adult T-cell leukemia/lymphoma (ATL) is an aggressive T-cell neoplasia associated with human T-cell leukemia virus type 1 (HTLV-1) infection and has an extremely poor prognosis. Lenalidomide (LEN; a second-generation immunomodulatory drug [IMiD]) has been employed as an additional therapeutic option for ATL since 2017, but its mechanism of action has not been fully proven, and recent studies reported emerging concerns about the development of second primary malignancies in patients treated with long-term IMiD therapy. Our purpose in this study was to elucidate the IMiD-mediated anti-ATL mechanisms. Thirteen ATL-related cell lines were divided into LEN-sensitive or LEN-resistant groups. CRBN knockdown (KD) led to a loss of LEN efficacy and IKZF2-KD-induced LEN efficacy in resistant cells. DNA microarray analysis demonstrated distinct transcriptional alteration after LEN treatment between LEN-sensitive and LEN-resistant ATL cell lines. Oral treatment of LEN for ATL cell-transplanted severe combined immunodeficiency (SCID) mice also indicated clear suppressive effects on tumor growth. Finally, a novel cereblon modulator (CELMoD), iberdomide (IBE), exhibited a broader and deeper spectrum of growth suppression to ATL cells with efficient IKZF2 degradation, which was not observed in other IMiD treatments. Based on these findings, our study strongly supports the novel therapeutic advantages of IBE against aggressive and relapsed ATL.

Adult T-cell leukemia/lymphoma (ATL), caused by human T-cell leukemia virus type-1 (HTLV-1) infection, is a malignant hematologic cancer that remains difficult to cure. We herein established a biomarker identification strategy based on the total cell proteomics of cultured ATL cells to search for novel ATL biomarkers. Four protocols with a combination of selected conditions based on lysis buffers and addition agents for total cell proteomics were used for a differential analysis between the ATL cell group (consisting of 11 cell lines), HTLV-1-infected cell group (consisting of 6 cell lines), and HTLV-1-negative cell group (consisting of 6 cell lines). In the analysis, we identified 24 and 27 proteins that were significantly increased (ratio >= 2.0, p < 0.05) and decreased (ratio <= 0.5, p < 0.05), respectively, in the ATL group. Previously reported CCL3 and CD30/TNFRSF8 were confirmed to be among significantly increased proteins. Furthermore, correlation analysis between identified proteins and Tax suggested that RASSF2 and GORASP2 were candidates of novel Tax-regulated factors. The biomarker identification strategy established herein is expected to contribute to the identification of biomarkers for ATL and other diseases.

There are more than 100 types of human pathogenic viruses, with seven currently known oncogenic viruses (Hulo et al., 2011). Hepatitis B (HBV)/C (HCV) viruses (Mohamed et al., 2023) and human papillomavirus (Wee et al., 2024) are pathogens of public health concern not only in Malaysia but also in many other countries, while Burkitt's lymphoma (Epstein-Barr virus) and Kaposi's sarcoma (Kaposi's sarcoma-associated herpesvirus) pose serious complications for AIDS patients (Carbone et al., 2022).

Adult T-cell leukemia/lymphoma (ATL) is an aggressive T-cell neoplasia associated with human T-cell leukemia virus type 1 (HTLV-1) infection and has an extremely poor prognosis. Lenalidomide (LEN; a second-generation immunomodulatory drug [IMiD]) has been employed as an additional therapeutic option for ATL since 2017, but its mechanism of action has not been fully proven, and recent studies reported emerging concerns about the development of second primary malignancies in patients treated with long-term IMiD therapy. Our purpose in this study was to elucidate the IMiD-mediated anti-ATL mechanisms. Thirteen ATL-related cell lines were divided into LEN-sensitive or LEN-resistant groups. CRBN knockdown (KD) led to a loss of LEN efficacy and IKZF2-KD-induced LEN efficacy in resistant cells. DNA microarray analysis demonstrated distinct transcriptional alteration after LEN treatment between LEN-sensitive and LEN-resistant ATL cell lines. Oral treatment of LEN for ATL cell-transplanted severe combined immunodeficiency (SCID) mice also indicated clear suppressive effects on tumor growth. Finally, a novel cereblon modulator (CELMoD), iberdomide (IBE), exhibited a broader and deeper spectrum of growth suppression to ATL cells with efficient IKZF2 degradation, which was not observed in other IMiD treatments. Based on these findings, our study strongly supports the novel therapeutic advantages of IBE against aggressive and relapsed ATL.

Regulatory T cells (Tregs) possess unique immunosuppressive activity among CD4-positive T cells. Tregs are ubiquitously present in mammals and function to calm excessive immune responses, thereby suppressing allergies or autoimmune diseases. On the other hand, due to their immunosuppressive function, Tregs are thought to promote cancer progression. The tumor microenvironment (TME) is a multicellular system composed of many cell types, including tumor cells, infiltrating immune cells, and cancer-associated fibroblasts (CAFs). Within this environment, Tregs are recruited by chemokines and metabolic factors and impede effective anti-tumor responses. However, in some cases, their presence can also improve patient’s survival rates. Their functional consequences may vary across tumor types, locations, and stages. An in-depth understanding of the precise roles and mechanisms of actions of Treg is crucial for developing effective treatments, emphasizing the need for further investigation and validation. This review aims to provide a comprehensive overview of the complex and multifaceted roles of Tregs within the TME, elucidating cellular communications, signaling pathways, and their impacts on tumor progression and highlighting their potential anti-tumor mechanisms through interactions with functional molecules.

Diffuse Large B-cell Lymphoma (DLBCL), with its intrinsic genetic and epigenetic heterogeneity, exhibits significantly variable clinical outcomes among patients treated with the current standard regimen. Disulfidptosis, a novel form of regulatory cell death triggered by disulfide stress, is characterized by the collapse of cytoskeleton proteins and F-actin due to intracellular accumulation of disulfides. We investigated the expression variations of disulfidptosis-related genes (DRGs) in DLBCL using two publicly available gene expression datasets. The initial analysis of DRGs in DLBCL (GSE12453) revealed differences in gene expression patterns between various normal B cells and DLBCL. Subsequent analysis (GSE31312) identified DRGs strongly associated with prognostic outcomes, revealing eight characteristic DRGs (CAPZB, DSTN, GYS1, IQGAP1, MYH9, NDUFA11, NDUFS1, OXSM). Based on these DRGs, DLBCL patients were stratified into three groups, indicating that (1) DRGs can predict prognosis, and (2) DRGs can help identify novel therapeutic candidates. This study underscores the significant role of DRGs in various biological processes within DLBCL. Assessing the risk scores of individual DRGs allows for more precise stratification of prognosis and treatment strategies for DLBCL patients, thereby enhancing the effectiveness of clinical practice.

N-myc downstream-regulated gene 2 (NDRG2), which is a tumour suppressor, is frequently lost in many types of tumours, including adult T-cell leukaemia/lymphoma (ATL). The downregulation of NDRG2 expression is involved in tumour progression through the aberrant phosphorylation of several important signalling molecules. We observed that the downregulation of NDRG2 induced the translocation of protein arginine methyltransferase 5 (PRMT5) from the nucleus to the cytoplasm via the increased phosphorylation of PRMT5 at Serine 335. In NDRG2low ATL, cytoplasmic PRMT5 enhanced HSP90A chaperone activity via arginine methylation, leading to tumour progression and the maintenance of oncogenic client proteins. Therefore, we examined whether the inhibition of PRMT5 activity is a drug target in NDRG2low tumours. The knockdown of PRMT5 and binding partner methylsome protein 50 (MEP50) expression significantly demonstrated the suppression of cell proliferation via the degradation of AKT and NEMO in NDRG2low ATL cells, whereas NDRG2-expressing cells did not impair the stability of client proteins. We suggest that the relationship between PRMT5/MEP50 and the downregulation of NDRG2 may exhibit a novel vulnerability and a therapeutic target. Treatment with the PRMT5-specific inhibitors CMP5 and HLCL61 was more sensitive in NDRG2low cancer cells than in NDRG2-expressing cells via the inhibition of HSP90 arginine methylation, along with the degradation of client proteins. Thus, interference with PRMT5 activity has become a feasible and effective strategy for promoting cancer vulnerability in NDRG2low ATL.

Abstract Background The immunomodulatory drug lenalidomide, which is now widely used for the treatment of multiple myeloma (MM), exerts pharmacological action through the ubiquitin‐dependent degradation of IKZF1 and subsequent down‐regulation of interferon regulatory factor 4 (IRF4), a critical factor for the survival of MM cells. IKZF1 acts principally as a tumour suppressor via transcriptional repression of oncogenes in normal lymphoid lineages. In contrast, IKZF1 activates IRF4 and other oncogenes in MM cells, suggesting the involvement of unknown co‐factors in switching the IKZF1 complex from a transcriptional repressor to an activator. The transactivating components of the IKZF1 complex might promote lenalidomide resistance by residing on regulatory regions of the IRF4 gene to maintain its transcription after IKZF1 degradation. Methods To identify unknown components of the IKZF1 complex, we analyzed the genome‐wide binding of IKZF1 in MM cells using chromatin immunoprecipitation‐sequencing (ChIP‐seq) and screened for the co‐occupancy of IKZF1 with other DNA‐binding factors on the myeloma genome using the ChIP‐Atlas platform. Results We found that c‐FOS, a member of the activator protein‐1 (AP‐1) family, is an integral component of the IKZF1 complex and is primarily responsible for the activator function of the complex in MM cells. The genome‐wide screening revealed the co‐occupancy of c‐FOS with IKZF1 on the regulatory regions of IKZF1‐target genes, including IRF4 and SLAMF7, in MM cells but not normal bone marrow progenitors, pre‐B cells or mature T‐lymphocytes. c‐FOS and IKZF1 bound to the same consensus sequence as the IKZF1 complex through direct protein‐protein interactions. The complex also includes c‐JUN and IKZF3 but not IRF4. Treatment of MM cells with short‐hairpin RNA against FOS or a selective AP‐1 inhibitor significantly enhanced the anti‐MM activity of lenalidomide in vitro and in two murine MM models. Furthermore, an AP‐1 inhibitor mitigated the lenalidomide resistance of MM cells. Conclusions C‐FOS determines lenalidomide sensitivity and mediates drug resistance in MM cells as a co‐factor of IKZF1 and thus, could be a novel therapeutic target for further improvement of the prognosis of MM patients.

Ferroptosis, a regulated cell death dependent on iron, has garnered attention as a potential broad-spectrum anticancer approach in leukemia research. However, there has been limited ferroptosis research on ATL, an aggressive T-cell malignancy caused by HTLV-1 infection. Our study employs bioinformatic analysis, utilizing dataset GSE33615, to identify 46 ferroptosis-related DEGs and 26 autophagy-related DEGs in ATL cells. These DEGs are associated with various cellular responses, chemical stress, and iron-related pathways. Autophagy-related DEGs are linked to autophagy, apoptosis, NOD-like receptor signaling, TNF signaling, and the insulin resistance pathway. PPI network analysis revealed 10 hub genes and related biomolecules. Moreover, we predicted crucial miRNAs, transcription factors, and potential pharmacological compounds. We also screened the top 20 medications based on upregulated DEGs. In summary, our study establishes an innovative link between ATL treatment and ferroptosis, offering promising avenues for novel therapeutic strategies in ATL.

Both natural viral infections and therapeutic interventions using viral vectors pose significant risks of malignant transformation. Monitoring for clonal expansion of infected cells is important for detecting cancer. Here we developed a novel method of tracking clonality via the detection of transgene integration sites. RAISING (Rapid Amplification of Integration Sites without Interference by Genomic DNA contamination) is a sensitive, inexpensive alternative to established methods. Its compatibility with Sanger sequencing combined with our CLOVA (Clonality Value) software is critical for those without access to expensive high throughput sequencing. We analyzed samples from 688 individuals infected with the retrovirus HTLV-1, which causes adult T-cell leukemia/lymphoma (ATL) to model our method. We defined a clonality value identifying ATL patients with 100% sensitivity and 94.8% specificity, and our longitudinal analysis also demonstrates the usefulness of ATL risk assessment. Future studies will confirm the broad applicability of our technology, especially in the emerging gene therapy sector.

Objective: Gastric cancer is an important cause of mortality in Sabah, Malaysia, but the prevalence of Helicobacter pylori infection in this state is unknown. Serology is an important tool for the surveillance of H. pylori infection. The objective of this study was to determine the prevalence of H. pylori infection by serology, and to provide information for policy discussions on H. pylori control programmes in Sabah.Methods: This cross-sectional study analysed serum samples collected from blood donors in a hospital in Kota Kinabalu, Sabah. H. pylori antibody concentration was measured using a commercially available kit.Results: The prevalence of H. pylori was 28.4% (204/718), and the infection rate was highest in subjects aged 30-39 years. Men were more likely to be infected than women. The H. pylori infection rate was highest among those of Kadazan (19.1%) ethnicity, followed by Dusun (15.7%), Bajau (14.7%) and Rungus (10.8%). Binary logistic regression analysis indicated that Chinese ( P = 0.026) and Malay ( P = 0.035) ethnicities were protective against H. pylori infection compared with other ethnicities.Conclusions: The seropositivity rate of H. pylori in this study was similar to the overall seropositivity rate in Malaysia; however, Chinese and Malay ethnicities were found to be protective against H. pylori infection.

Adult T-cell leukemia/lymphoma (ATL) is a highly chemoresistant malignancy of peripheral T lymphocytes caused by human T-cell leukemia virus type 1 infection, for which there is an urgent need for more effective therapeutic options. The molecular chaperone heat shock protein 90 (HSP90) plays a crucial role in nuclear factor-κB (NF-κB)-mediated antiapoptosis in ATL cells, and HSP90 inhibitors are new candidate therapeutics for ATL. Accordingly, we investigated the anti-ATL effects of a novel oral HSP90 inhibitor, TAS-116 (pimitespib), and the mechanisms involved in ex vivo and in vivo preclinical models. TAS-116 achieved IC50 values of less than 0.5 μmol/L in 10 ATL-related cell lines and less than 1 μmol/L in primary peripheral blood cells of nine ATL patients; no toxicity was observed toward CD4+ lymphocytes from healthy donors, indicating the safety of this agent. Given orally, TAS-116 also showed significant inhibitory effects against tumor cell growth in ATL cell-xenografted mice. Furthermore, gene expression profiling of TAS-116-treated Tax-positive or -negative cell lines and primary ATL cells using DNA microarray and multiple pathway analysis revealed the significant downregulation of the NF-κB pathway in Tax-positive cells and cell-cycle arrest in Tax-negative cells and primary ATL cells. TAS-116 suppressed the activator protein-1 and tumor necrosis factor pathways in all examined cells. These findings strongly indicate the efficacy of TAS-116, regardless of the stage of ATL progression, and its potential application as a novel clinical anti-ATL therapeutic agent.

Respiratory syncytial virus (RSV) is the main cause of acute respiratory infections in young children, and also has a major impact in the elderly and immunocompromised people. In the absence of vaccine or efficient treatment, a better understanding of RSV interactions with the host antiviral response during infection is needed. Previous studies revealed that cytoplasmic inclusion bodies (IBs) where viral replication and transcription occur could play a major role in the control of innate immunity during infection by recruiting cellular proteins involved in the host antiviral response. We recently showed that the morphogenesis of IBs relies on a liquid-liquid phase separation mechanism depending on the interaction between viral nucleoprotein (N) and phosphoprotein (P). These scaffold proteins are expected to play a central role in the recruitment of cellular proteins to IBs. Here, we performed a yeast two-hybrid screen using RSV N protein as a bait, and identified the cellular protein TAX1BP1 as a potential partner of N. This interaction was validated by pulldown and immunoprecipitation assays. We showed that TAX1BP1 suppression has only a limited impact on RSV infection in cell cultures. On the contrary, in vivo experiments showed that RSV replication is decreased in TAX1BP1KO mice, whereas the production of inflammatory and antiviral cytokines is enhanced. In vitro infection of either wild-type or TAX1BP1KO alveolar macrophages confirmed that the innate immune response to RSV infection is enhanced in the absence of TAX1BP1. Altogether, our results suggest that RSV could hijack TAX1BP1 to restrain the host immune response during infection. Importance Respiratory syncytial virus (RSV), which is the leading cause of lower respiratory tract illness in infants, still remains a medical problem in the absence of vaccine or efficient treatment. This virus is also recognized as a main pathogen in the elderly and immunocompromised people, and the occurrence of co-infections (with other respiratory viruses and bacteria) amplifies the risks of developing respiratory distress. In this context, a better understanding of the pathogenesis associated to viral respiratory infections, which depends on both viral replication and the host immune response, is needed. The present study reveals that the cellular protein TAX1BP1, which interacts with the RSV nucleoprotein N, participates in the control of the innate immune response during RSV infection, suggesting that N-TAX1BP1 interaction represents a new target for the development of antivirals.

Objective: Rotavirus is one of the major causes of gastroenteritis in children under 5 years of age. It can evolve by reassortment, in which gene segments are exchanged between strains of different origins. In some rotavirus strains the P[ 9] component is an example of reassortment, in which the P[9] genotype is from feline species. A number of outbreaks associated with P[9] strains have been documented in several countries. However, details regarding the epidemiological relationships between the strains remains largely unknown. Therefore, in the present study, genetic characterization and evolutionary analyses were performed to gain insight into P[9] strains circulating in different parts of the world. Materials and Methods: A total of 94 full-and partial-length VP4 gene sequences of P[9] strains were extracted from GenBank and phylogenetic trees were constructed by maximum likelihood method. Timeline of evolution was performed using the full-length nucleotide sequences of VP4 genes of P[9] strains using the Bayesian Markov Chain Monte Carlo method available in BEAST version 1.6.1. Results: The VP4 gene of the P[9] strains could be divided into two lineages, with lineage I is further divided into five sub-lineages. All the P[9] strains characterized in this study shared a common ancestor that circulated in circa 1864 (95% HPD 1755-1941). In each lineage, the strains were not only from different countries, but also from different continents. These findings suggest that none of the lineages has a specific region of distribution, and although humans have had interactions with cats for thousands of years, the common ancestor of the VP4 gene of the current P[9] strains is relatively recent. Conclusion: These findings suggest that P[9] rotaviruses can be divided into two lineages. None of the lineages and sub-lineages has a specific region of distribution, and the ancestor of the current P[9] strain is relatively recent.

Energy-metabolism oscillations (EMO) are ultradian biological rhythms observed in in aerobic chemostat cultures of Saccharomyces cerevisiae. EMO regulates energy metabolism such as glucose, carbohydrate storage, O2 uptake, and CO2 production. PSK1 is a nutrient responsive protein kinase involved in regulation of glucose metabolism, sensory response to light, oxygen, and redox state. The aim of this investigation was to assess the function of PSK1 in regulation of EMO. The mRNA levels of PSK1 fluctuated in concert with EMO, and deletion of PSK1 resulted in unstable EMO with disappearance of the fluctuations and reduced amplitude, compared with the wild type. Furthermore, the mutant PSK1Δ showed downregulation of the synthesis and breakdown of glycogen with resultant decrease in glucose concentrations. The redox state represented by NADH also decreased in PSK1Δ compared with the wild type. These data suggest that PSK1 plays an important role in the regulation of energy metabolism and stabilizes ultradian biological rhythms. These results enhance our understanding of the mechanisms of biorhythms in the budding yeast.

Approximately 10–20 million of Human T-cell leukemia virus type-1 (HTLV-1)-infected carriers have been previously reported, and approximately 5% of these carriers develop adult T-cell leukemia/lymphoma (ATL) with a characteristic poor prognosis. In Japan, Southern blotting has long been routinely performed for detection of clonally expanded ATL cells in vivo, and as a confirmatory diagnostic test for ATL. However, alternative methods to Southern blotting, such as sensitive, quantitative, and rapid analytical methods, are currently required in clinical practice. In this study, we developed a high-throughput method called rapid amplification of integration site (RAIS) that could amplify HTLV-1-integrated fragments within 4 h and detect the integration sites in > 0.16% of infected cells. Furthermore, we established a novel quantification method for HTLV-1 clonality using Sanger sequencing with RAIS products, and the validity of the quantification method was confirmed by comparing it with next-generation sequencing in terms of the clonality. Thus, we believe that RAIS has a high potential for use as an alternative routine molecular confirmatory test for the clonality analysis of HTLV-1-infected cells.

Outbreaks of diarrhea in kindergartens are underreported and frequently go unnoticed in developing countries. To better understand the etiology this study was performed during an outbreak of diarrhea in a kindergarten in Sabah, Malaysia. Outbreak investigation was performed according to the standard procedures. In this outbreak a total of 34 (36.5%) children and 4 (30.8%) teachers suffered from gastroenteritis. Stool samples from seven children and 13 teachers were tested for rotavirus and norovirus. During the investigation stool samples were collected and sent in cold chain to the laboratory. The samples were subjected to rotavirus enzyme linked immunosorbent assay, and reverse transcription PCR for norovirus. All samples were negative for rotavirus but positive for norovirus. To determine the genogroup and genotype of norovirus, nucleotide sequencing of the amplicons was performed. All norovirus from the outbreak was of genotype GII.2[16]. To determine the relatedness of the strains phylogenetic analysis was done using neighbor-joining method. Phylogenetically these strains were highly related to GII.2[P16] noroviruses from China and Japan. This study provided evidence that a diarrheal outbreak in a kindergarten was caused by GII.2[P16] norovirus which is an emerging strain in East Asia and Europe.

Objectives: Rotavirus is one of the major causes of gastroenteritis in children under 5 years of age and is responsible for over 200,000 deaths annually. Rotavirus can evolve by reassortment, in which gene segments are exchanged between strains of different origins. Rotavirus strains with the P[9] genotype is an example of reassortment, in which the P[9] genotype is from feline species. A number of outbreaks associated with P[9] strains have been documented in several countries. However, details regarding the epidemiological relationships between the strains remains largely unknown. Therefore, in the present study, genetic characterization and evolutionary analyses were performed to gain insight into P[9] strains circulating in different parts of the world. Results: The VP4 gene of the P[9] strains could be divided into six lineages, and P[9] strains characterized in this study share a common ancestor that circulated in circa 1864. In each lineage, the strains were not only from different countries, but also from different continents. These findings suggest that none of the lineages has a specific region of distribution, and although humans have had interactions with cats for thousands of years, the common ancestor of the VP4 gene of the current P[9] strains is relatively recent.

Objectives: Rotavirus is one of the major causes of gastroenteritis in children under 5 years of age and is responsible for over 200,000 deaths annually. Rotavirus can evolve by reassortment, in which gene segments are exchanged between strains of different origins. Rotavirus strains with the P[9] genotype is an example of reassortment, in which the P[9] genotype is from feline species. A number of outbreaks by P[9] strains have been documented in several countries. However, details regarding the epidemiological relationships between the strains remains largly unknown. Therefore, in the present study, genetic characterization and evolutionary analyses were perforemd to gain insight into P[9] strains circulating in different parts of the world. Results: The P[9] strains could be divided into five lineages, and that the common ancestor of currently circulating P[9] strains is around 168 years old. In each lineage, the strains were not only from different countries, but also from different continents. These findings suggest that none of the lineages has a specific region of distribution, and although humans have had interactions with cats for thousands of years, the ancestor of the current P[9] strain is relatively recent.