Phosphorylated STAT3 expression predicts better prognosis in smoldering type of adult T-cell leukemia/lymphoma

Pro-inflammatory cytokine expression and the STAT1/3 pathway in canine chronic enteropathy and intestinal T-cell lymphoma

The accumulation of intraepithelial lymphocytes (IELs) is a histopathological feature of canine chronic enteropathy (CE), and IELs are considered the cells of origin of intestinal T-cell lymphoma (ITCL). However, the pathogenic mechanism of IEL activation in CE remains unclear. This study hypothesized that the expression of proinflammatory cytokines, associated with cytotoxic T/NK-cell activation, is upregulated in CE and ITCL, and examined the expression of IFN-γ, IL-2, IL-12p35, IL-12p40, IL-15, and IL-21 and the downstream signal transducers and activators of transcription (STAT) pathway in the duodenal mucosa of dogs without lesions (n = 11; NC), with IEL-CE (n = 19; CE without intraepithelial lymphocytosis), IEL+CE (n = 29; CE with intraepithelial lymphocytosis), and with ITCL (n = 60). Quantitative polymerase chain reaction (PCR) revealed that IFN-γ and IL-21 were higher in IEL+CE than in IEL-CE or NC. Western blot revealed upregulation of STAT1 and STAT3 in IEL+CE. Double-labeling immunohistochemistry revealed a positive correlation between the Ki67 index of CD3+ T-cells and IFN-γ expression levels. Immunohistochemistry revealed a higher ratio of p-STAT1-positive villi in IEL+CE and ITCL than IEL-CE and NC, which positively correlated with IFN-γ expression levels. Among the 60 ITCL cases, neoplastic lymphocytes were immunopositive for p-STAT1 in 28 cases and p-STAT3 in 29 cases. These results suggest that IFN-γ and IL-21 contribute to the pathogenesis of IEL+CE, and IFN-γ may be involved in T-cell activation and mucosal injury in CE. STAT1 and STAT3 activation in ITCL cells suggests a role for the upregulation of the STAT pathway in the pathogenesis of ITCL.

The Novel Link between Gene Expression Profiles of Adult T-Cell Leukemia/Lymphoma Patients' Peripheral Blood Lymphocytes and Ferroptosis Susceptibility

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.

Prognostic analysis of smoldering ATLL with skin eruptions based on genomic aberrations

BACKGROUND

Patients with smoldering ATLL often present with a skin eruption due to skin infiltration of ATLL cells. Although skin eruption type is known to be associated with prognosis based on its pattern, it is unknown why different types of skin eruptions are associated with different prognoses.

OBJECTIVE

Genomic analysis of patients with skin eruptions of smoldering ATLL will be performed to determine the mechanism of ATLL development and its association with prognosis.

METHODS

DNA from skin biopsy specimens was used for targeted sequencing of 280 genes to examine the association between genomic variation and prognosis.

RESULTS

Due to the small number of smoldering ATLL patients (27 cases), we could not find a clear relationship between skin eruption and prognosis in this study. Genomic analysis identified 247 genomic variants (108 genes), with an average of 9.2 variants and 3.2 variants as driver genes. Pathway analysis of the driver genes showed activation of the pathway associated with HTLV-1 infection, as well as activation of the signaling pathway observed throughout ATLL. Furthermore, multivariate analysis identified age>70 years and STAT3 mutation as prognostic risk factors and TBL1XR1 mutation as a risk factor for progression-free survival.

CONCLUSION

Although the small number of patient samples did not allow us to determine a prognostic association with skin eruption, STAT3 mutation was identified as a prognostic risk factor for smoldering ATLL with skin eruption. Further studies are needed to increase the number of patients with this disease.

Genome-wide CRISPR screens identify CD48 defining susceptibility to NK cytotoxicity in peripheral T-cell lymphomas

Adult T-cell leukemia/lymphoma (ATLL) is one of the aggressive peripheral T-cell neoplasms with a poor prognosis. Accumulating evidence demonstrates that escape from adaptive immunity is a hallmark of ATLL pathogenesis. However, the mechanisms by which ATLL cells evade natural killer (NK)-cell-mediated immunity have been poorly understood. Here we show that CD48 expression in ATLL cells determines the sensitivity for NK-cell-mediated cytotoxicity against ATLL cells. We performed unbiased genome-wide clustered regularly interspaced short palindromic repeat (CRISPR) screening using 2 ATLL-derived cell lines and discovered CD48 as one of the best-enriched genes whose knockout conferred resistance to YT1-NK cell line-mediated cytotoxicity. The ability of CD48-knockout ATLL cells to evade NK-cell effector function was confirmed using human primary NK cells with reduced interferon-γ (IFNγ) induction and degranulation. We found that primary ATLL cells had reduced CD48 expression along with disease progression. Furthermore, other subgroups among aggressive peripheral T-cell lymphomas (PTCLs) also expressed lower concentrations of CD48 than normal T cells, suggesting that CD48 is a key molecule in malignant T-cell evasion of NK-cell surveillance. Thus, this study demonstrates that CD48 expression is likely critical for malignant T-cell lymphoma cell regulation of NK-cell-mediated immunity and provides a rationale for future evaluation of CD48 as a molecular biomarker in NK-cell-associated immunotherapies.

From drug repositioning to target repositioning: prediction of therapeutic targets using genetically perturbed transcriptomic signatures

Motivation

A critical element of drug development is the identification of therapeutic targets for diseases. However, the depletion of therapeutic targets is a serious problem.

Results

In this study, we propose the novel concept of target repositioning, an extension of the concept of drug repositioning, to predict new therapeutic targets for various diseases. Predictions were performed by a trans-disease analysis which integrated genetically perturbed transcriptomic signatures (knockdown of 4345 genes and overexpression of 3114 genes) and disease-specific gene transcriptomic signatures of 79 diseases. The trans-disease method, which takes into account similarities among diseases, enabled us to distinguish the inhibitory from activatory targets and to predict the therapeutic targetability of not only proteins with known target–disease associations but also orphan proteins without known associations. Our proposed method is expected to be useful for understanding the commonality of mechanisms among diseases and for therapeutic target identification in drug discovery.

Availability and implementation

Supplemental information and software are available at the following website [http://labo.bio.kyutech.ac.jp/~yamani/target_repositioning/].

Supplementary information

Supplementary data are available at Bioinformatics online.

The Positivity of Phosphorylated STAT3 Is a Novel Marker for Favorable Prognosis in Germinal Center B-Cell Type of Diffuse Large B-Cell Lymphoma

On the basis of immunohistochemistry, diffuse large B-cell lymphoma (DLBCL) is categorized as a germinal center B-cell (GCB) or non-GCB subtype. Recent integrated genomic analyses have highlighted the importance of the JAK-STAT3 pathway in the molecular pathogenesis of DLBCL. However, its relevance to clinical outcomes remains controversial. Therefore, we evaluated the extent of the nuclear expression of phosphorylated STAT3 (pSTAT3), a surrogate marker of signal transducer and activator of transcription 3 (STAT3) activation, by immunohistochemistry. We also analyzed the potential relationship between pSTAT3 positivity (defined as ≥40% positive neoplastic cells) and clinicopathologic characteristics in 294 patients with DLBCL. pSTAT3 was detected in 122 patients (42%), with a higher rate in the non-GCB subtype than in the GCB subtype (57% vs. 28%, P<0.001). Factors potentially activating STAT3, MYD88L265P, and Epstein-Barr virus-encoded small RNA were identified in the pSTAT3-positive non-GCB subtype, whereas the pSTAT3-positive GCB subtype often showed STAT3 mutations and lacked EZH2 mutations and the rearrangements of BCL2 and MYC. Multivariate analyses revealed that the pSTAT3-positive GCB subtype showed a favorable prognosis (HR: 0.17; 95% confidence interval, 0.04-0.7; P=0.014). These findings suggest that pSTAT3 positivity may have a unique impact on the clinicopathologic characteristics of DLBCL, making it a promising novel marker for the favorable prognosis of patients with the GCB subtype.

Clinicopathological features of adult T-cell leukemia/lymphoma with HTLV-1-infected Hodgkin and Reed-Sternberg-like cells

Hodgkin and Reed-Sternberg (HRS) cells, a hallmark of classic Hodgkin lymphoma (CHL), are occasionally detected in non-Hodgkin lymphomas, including adult T-cell leukemia/lymphoma (ATLL), a lymphoid neoplasm caused by human T-cell leukemia virus type 1 (HTLV-1). HRS-like cells associated with ATLL have been described to be of B-cell lineage and infected with Epstein-Barr virus (EBV), not HTLV-1. We herein describe clinicopathological findings in 8 cases (4 males and 4 females; median age, 73 years [range, 55-81 years]) of ATLL with HTLV-1-infected HRS-like cells identified by ultrasensitive RNA in situ hybridization for HTLV-1 basic leucine zipper factor (HBZ-ISH), a specific viral transcript of HTLV-1. All patients showed nodal or mediastinal lesions, and 5 of the 8 patients were at an advanced disease stage. HRS-like cells were positive for CD30, CD15, MUM1, CD25, and HBZ-ISH and negative for B-cell markers, including PAX5, pan-T-cell antigens, and EBV in all cases. Five cases were positive for CD4, and 6 cases were positive for fascin. HBZ was identified in both HRS-like cells and surrounding lymphoid cells in 1 case with an aggressive clinical course and only HRS-like cells in 7 cases, most of whom showed a clinical response regardless of the chemotherapeutic regimen. Even though the definitive lineage typing of the HTLV-1-infected HRS cells is one of the limitations of this study in the absence of single-cell microdissection for polymerase chain reaction analysis, the combination of diffuse HBZ-ISH positivity and negativity for PAX5 and EBV deemed these cases distinct from CHL arising in HTLV-1 carriers.

A new diagnostic algorithm using biopsy specimens in adult T-cell leukemia/lymphoma: combination of RNA in situ hybridization and quantitative PCR for HTLV-1

Histopathological distinction between adult T-cell leukemia/lymphoma (ATLL) and other T-cell neoplasms is often challenging. The current gold standard for the accurate diagnosis of ATLL is the Southern blot hybridization (SBH) assay, which detects clonal integration of human T-cell leukemia virus type I (HTLV-1) provirus. However, SBH cannot be performed with small biopsy or formalin-fixed paraffin-embedded (FFPE) tissue samples because this assay requires a large amount of DNA without degradation. Here we developed a new diagnostic algorithm for the accurate diagnosis of ATLL using FFPE samples. This method combines two HTLV-1 detection assays, namely, ultrasensitive RNA in situ hybridization using RNAscope for HTLV-1 bZIP factor (HBZ-RNAscope), and quantitative PCR targeting the tax gene (tax-qPCR). We analyzed 119 FFPE tissue specimens (62 ATLL, and 57 non-ATLL, including 41 HTLV-1 carriers) and compared them with the SBH results using the corresponding fresh-frozen samples. As a result, tax-qPCR had a higher ATLL identification rate than HBZ-RNAscope (88% [52/59], and 63% [39/62], respectively). However, HBZ-RNAscope clearly visualized the localization of HTLV-1-infected tumor cells and its identification rate increased to 94% (17/18) when the analysis was limited to samples up to 2 years old, indicating its usefulness in the daily diagnosis. The diagnostic algorithm combining these two assays successfully evaluated 94% (112/119) of samples and distinguished ATLL from non-ATLL cases including HTLV-1 carriers with 100% sensitivity and specificity. This method is expected to replace SBH and increase the accuracy of the diagnosis of ATLL.

Functional network analysis reveals potential repurposing of β-blocker atenolol for pancreatic cancer therapy

BACKGROUND

The survival rate of patients with pancreatic cancer is low; therefore, continuous discovery and development of novel pancreatic cancer drugs are required. Functional network analysis is an integrated bioinformatics approach based on gene, target, and disease networks interaction, and it is extensively used in drug discovery and development.

OBJECTIVE

This study aimed to identify if atenolol, a selective adrenergic inhibitor, can be repurposed for the treatment of pancreatic cancer using functional network analysis.

METHODS

Direct target proteins (DTPs) and indirect target proteins (ITPs) were obtained from STITCH and STRING databases, respectively. Atenolol-mediated proteins (AMPs) were collected from DTPs and ITPs and further analyzed for gene ontology, KEGG pathway enrichment, genetic alterations, overall survival, and molecular docking.

RESULTS

We obtained 176 AMPs that consisted of 10 DTPs and 166 ITPs. Among the AMPs involved in the pancreatic cancer pathways, several AMPs such as MAPK1, RELA, MAPK8, STAT1, and STAT3 were identified. Genetic alterations in seven AMPs were identified in 0.9%-16% of patients. Patients with high mRNA levels of MAPK1, RELA, STAT3, GNB1, and MMP9 had significantly worse overall survival rates compared with patients with low expression. Molecular docking studies showed that RELA and MMP9 are potential target candidates of atenolol in the treatment of patients with pancreatic cancer.

CONCLUSION

In conclusion, atenolol can potentially be repurposed to target pancreatic cancer cells by modulating MMP9 and NF-κB signaling. The results of this study need to be further validated in vitro and in vivo.

STAT3 Activation Is Associated with Interleukin-10 Expression and Survival in Primary Central Nervous System Lymphoma

BACKGROUND

The findings from several studies have confirmed that signal transducer and activator of transcription 3 (STAT3) is constitutively phosphorylated in primary central nervous system lymphoma (PCNSL). However, the underlying mechanism and prognostic significance of STAT3 activation have not yet been clarified.

METHODS

The expression of STAT3, phosphorylated STAT3 (p-STAT3), and interleukin (IL)-10 was examined in 32 PCNSL samples using immunohistochemistry. The relationship between IL-10 expression and STAT3 phosphorylation was determined. In addition, the associations of the expression of these proteins with the clinical factors and survival were analyzed.

RESULTS

Expression of STAT3, p-STAT3, and IL-10 was detected in 28 (87.5%), 17 (53.1%), and 25 (78.1%) samples, respectively. IL-10 expression was significantly associated with STAT3 phosphorylation in PCNSL (P = 0.033). STAT3 phosphorylation and IL-10 expression were associated with the presence of multiple brain lesions (P = 0.004 and P = 0.027, respectively), suggesting that STAT3 activation might enhance the intracranial spread of tumors in PCNSL. The 2-year overall survival and progression-free survival (PFS) rates were 67.8% and 35.5%, respectively. Kaplan-Meier survival analysis demonstrated that STAT3 phosphorylation, IL-10 expression, and multiple brain lesions were significantly associated with PFS in those with PCNSL (P = 0.009, P = 0.030, and P = 0.040, respectively). However, Cox regression analysis indicated that only STAT3 phosphorylation was significantly associated with shorter PFS (hazard ratio, 3.22; 95% confidence interval, 1.24-8.37; P = 0.016).

CONCLUSION

Our results have indicated that STAT3 activation is closely related to IL-10 expression and that p-STAT3 might be a novel biomarker predictive of poor survival in those with PCNSL.

STAT3 Dysregulation in Mature T and NK Cell Lymphomas

Abstract: T cell lymphomas comprise a distinct class of non-Hodgkin's lymphomas, which include mature T and natural killer (NK) cell neoplasms. While each malignancy within this group is characterized by unique clinicopathologic features, dysregulation in the Janus tyrosine family of kinases/Signal transducer and activator of transcription (JAK/STAT) signaling pathway, specifically aberrant STAT3 activation, is a common feature among these lymphomas. The mechanisms driving dysregulation vary among T cell lymphoma subtypes and include activating mutations in upstream kinases or STAT3 itself, formation of oncogenic kinases which drive STAT3 activation, loss of negative regulators of STAT3, and the induction of a pro-tumorigenic inflammatory microenvironment. Constitutive STAT3 activation has been associated with the expression of targets able to increase pro-survival signals and provide malignant fitness. Patients with dysregulated STAT3 signaling tend to have inferior clinical outcomes, which underscores the importance of STAT3 signaling in malignant progression. Targeting of STAT3 has shown promising results in pre-clinical studies in T cell lymphoma lines, ex-vivo primary malignant patient cells, and in mouse models of disease. However, targeting this pleotropic pathway in patients has proven difficult. Here we review the recent contributions to our understanding of the role of STAT3 in T cell lymphomagenesis, mechanisms driving STAT3 activation in T cell lymphomas, and current efforts at targeting STAT3 signaling in T cell malignancies.

Phosphorylated STAT3 expression predicts better prognosis in smoldering type of adult T-cell leukemia/lymphoma

Adult T‐cell leukemia/lymphoma (ATLL) is a mature T‐cell neoplasm, and is divided into 2 indolent (smoldering and chronic) and 2 aggressive (acute and lymphoma) clinical subtypes. Based on previous integrated molecular analyses suggesting the importance of the JAK‐STAT pathway in ATLL, we attempted to clarify the clinicopathological significance of this pathway. Clinical and morphological findings were reviewed in 116 cases with ATLL. The nuclear localizations of phosphorylated STAT3 (pSTAT3), pSTAT5, and pSTAT6 were analyzed by immunohistochemistry. Targeted sequencing was undertaken on the portion of STAT3 encoding the Src homology 2 domain. Expression of pSTAT3 was observed in 43% (50/116) of ATLL cases, whereas pSTAT5 and pSTAT6 were largely undetected. Cases with the lymphoma type showed significantly less frequent pSTAT3 expression (8/45, 18%) than those with the other subtypes (41/66, 62%; P < .001). STAT3 mutations were detected in 36% (10/28) and 19% (12/64) of cases with the smoldering and aggressive types of ATLL, respectively. The correlation between STAT3 mutation and pSTAT3 expression was not significant (P = .07). Both univariate and multivariate analysis revealed that pSTAT3 expression was significantly associated with better overall survival and progression‐free survival in the smoldering type of ATLL, whereas STAT3 mutation was not related to a line of clinical outcome. Collectively, our data show that only the lymphoma type showed a low prevalence of tumor cells positive for pSTAT3 expression, and raises the possibility that pSTAT3 expression is a novel biomarker to predict better prognosis in the smoldering type of ATLL.