SMARCA5 reprograms AKR1B1-mediated fructose metabolism to control leukemogenesis.

A significant variation in chromatin accessibility is an epigenetic feature of leukemia. The cause of this variation in leukemia, however, remains elusive. Here, we identify SMARCA5, a core ATPase of the imitation switch (ISWI) chromatin remodeling complex, as being responsible for aberrant chromatin accessibility in leukemia cells. We find that SMARCA5 is required to maintain aberrant chromatin accessibility for leukemogenesis and then promotes transcriptional activation of AKR1B1, an aldo/keto reductase, by recruiting transcription co-activator DDX5 and transcription factor SP1. Higher levels of AKR1B1 are associated with a poor prognosis in leukemia patients and promote leukemogenesis by reprogramming fructose metabolism. Moreover, pharmacological inhibition of AKR1B1 has been shown to have significant therapeutic effects in leukemia mice and leukemia patient cells. Thus, our findings link the aberrant chromatin state mediated by SMARCA5 to AKR1B1-mediated endogenous fructose metabolism reprogramming and shed light on the essential role of AKR1B1 in leukemogenesis, which may provide therapeutic strategies for leukemia.

[Chidamide Promotes Osteogenic Differentiation of Bone Marrow Mesenchymal Stromal Cells from Patients with Myelodysplastic Syndromes].

OBJECTIVE: To explore the effects and mechanisms of chidamide on the osteogenic differentiation of bone marrow mesenchymal stromal cells (MSC) from myelodysplastic syndromes (MDS). METHODS: MSC were isolated and cultured from bone marrow of MDS patients and healthy donors. CCK-8 assay was used to detect the effects of chidamide on the proliferation of MSC. The effects of chidamide on the activity of histone deacetylase (HDAC) in MSC was measured by a fluorescence assay kit and Western blot. Alkaline phosphatase (ALP) activity was detected on day 3 and calcium nodule formation was observed by Alizarin Red staining on day 21 after osteogenic differentiation. The expression of early and late osteogenic genes was detected on day 7 and day 21, respectively. RT-PCR and Western blot were used to detect the effects of chidamide on mRNA and protein expression of RUNX2 which is the key transcription factor during osteogenesis. RESULTS: As the concentration of chidamide increased, the proliferation of MSC was inhibited. However, at a low concentration (1 µmol/L), chidamide had no significant inhibitory effect on MSC proliferation but significantly inhibited HDAC activity. In MSC from both MDS patients and healthy donors, chidamide (1 µmol/L) significantly increased ALP activity, calcium nodule formation, thereby mRNA expression of osteogenic genes, and restored the reduced osteogenic differentiation ability of MDS-MSC compared to normal MSC. Mechanistic studies showed that the osteogenic-promoting effect of chidamide may be related to the upregulation of RUNX2 . CONCLUSION: Chidamide can inhibit HDAC activity in MSC, upregulate the expression of the osteogenic transcription factor RUNX2, and promote the osteogenic differentiation of MDS-MSC.

The clinical characteristics, gene mutations and outcomes of myelodysplastic syndromes with diabetes mellitus.

PURPOSE: Diabetes mellitus (DM) is the second most common comorbidity in myelodysplastic syndromes (MDS). The purpose of the study was to investigate the clinical characteristics of MDS patients with DM. METHODS: A retrospective analysis was performed on the clinical data of 890 MDS patients with or without DM. Clinical data, including genetic changes, overall survival (OS), leukemia-free survival (LFS) and infection, were analyzed. RESULTS: Among 890 patients, 184 (20.7%) had DM. TET2 and SF3B1 mutations occurred more frequently in the DM group than those in the non-DM group (p = 0.0092 and p = 0.0004, respectively). Besides, DM was an independent risk factor for infection (HR 2.135 CI 1.451-3.110, p = 0.000) in MDS. Compared to non-DM patients, MDS patients with DM had poor OS and LFS (p = 0.0002 and p = 0.0017, respectively), especially in the lower-risk group. While in multivariate analysis, DM did not retain its prognostic significance and the prognostic significance of infection was maintained (HR 2.488 CI 1.749-3.538, p = 0.000). CONCLUSIONS: MDS patients with DM have an inferior prognosis which may due to higher infection incidence, with TET2 and SF3B1 mutations being more frequent in those cases.

Incorporating mutations and bone marrow fibrosis into the revised international prognostic scoring system in myelodysplastic syndromes.

The independent prognostic significance of bone marrow fibrosis (BMF) in myelodysplastic syndromes (MDS) is challenged under currently molecular prognostic models. In this study, the clinical and genetic data from 438 MDS patients were analyzed retrospectively. The patients were randomly divided into training (n = 306) and validation (n = 132) cohorts. The independent significant prognostic factors included age, IPSS-R, BMF, TP53 and U2AF1. Using their weighted coefficients, we developed a simplified prognostic system. Four risk groups were produced: low, intermediate, high and very high. The new model yielded more clearly separated survival curves than the IPSS-R. In addition, our model achieved higher C-indexes (0.61 in the training cohort and 0.63 in the validation cohort) than the IPSS-RM model (0.59 and 0.58) and IPSS-R (0.57 and 0.56). In conclusion, BMF was an independent significant prognostic factor for MDS, and adding BMF into the IPSS-R improved its predictive capability.

Decitabine induces IRF7-mediated immune responses in p53-mutated triple-negative breast cancer: a clinical and translational study.

p53 is mutated in half of cancer cases. However, no p53-targeting drugs have been approved. Here, we reposition decitabine for triple-negative breast cancer (TNBC), a subtype with frequent p53 mutations and extremely poor prognosis. In a retrospective study on tissue microarrays with 132 TNBC cases, DNMT1 overexpression was associated with p53 mutations (P = 0.037) and poor overall survival (OS) (P = 0.010). In a prospective DEciTabinE and Carboplatin in TNBC (DETECT) trial (NCT03295552), decitabine with carboplatin produced an objective response rate (ORR) of 42% in 12 patients with stage IV TNBC. Among the 9 trialed patients with available TP53 sequencing results, the 6 patients with p53 mutations had higher ORR (3/6 vs. 0/3) and better OS (16.0 vs. 4.0 months) than the patients with wild-type p53. In a mechanistic study, isogenic TNBC cell lines harboring DETECT-derived p53 mutations exhibited higher DNMT1 expression and decitabine sensitivity than the cell line with wild-type p53. In the DETECT trial, decitabine induced strong immune responses featuring the striking upregulation of the innate immune player IRF7 in the p53-mutated TNBC cell line (upregulation by 16-fold) and the most responsive patient with TNBC. Our integrative studies reveal the potential of repurposing decitabine for the treatment of p53-mutated TNBC and suggest IRF7 as a potential biomarker for decitabine-based treatments.

ROBO1 deficiency impairs HSPC homeostasis and erythropoiesis via CDC42 and predicts poor prognosis in MDS.

Myelodysplastic syndrome (MDS) is a group of clonal hematopoietic neoplasms originating from hematopoietic stem progenitor cells (HSPCs). We previously identified frequent roundabout guidance receptor 1 (ROBO1) mutations in patients with MDS, while the exact role of ROBO1 in hematopoiesis remains poorly delineated. Here, we report that ROBO1 deficiency confers MDS-like disease with anemia and multilineage dysplasia in mice and predicts poor prognosis in patients with MDS. More specifically, Robo1 deficiency impairs HSPC homeostasis and disrupts HSPC pool, especially the reduction of megakaryocyte erythroid progenitors, which causes a blockage in the early stages of erythropoiesis in mice. Mechanistically, transcriptional profiling indicates that Cdc42, a member of the Rho-guanosine triphosphatase family, acts as a downstream target gene for Robo1 in HSPCs. Overexpression of Cdc42 partially restores the self-renewal and erythropoiesis of HSPCs in Robo1-deficient mice. Collectively, our result implicates the essential role of ROBO1 in maintaining HSPC homeostasis and erythropoiesis via CDC42.

The bcl6 corepressor mutation regulates the progression and transformation of myelodysplastic syndromes by repressing the autophagy flux.

The occurrence of autophagy dysregulation is vital in the development of myelodysplastic syndrome and its transformation to acute myeloid leukemia. However, the mechanisms are largely unknown. Here, we have investigated the mechanism of the bcl6 corepressor mutation in myelodysplastic syndrome development and its transformation to acute myeloid leukemia. We identified a novel pathway involving histone deacetylase 6 and forkhead box protein O1, which leads to autophagy defects following the bcl6 corepressor mutation. And this further causes apoptosis and cell cycle arrest. The bcl6 corepressor-mutation-repressed autophagy resulted in the accumulation of damaged mitochondria, DNA, and reactive oxygen species in myelodysplastic syndrome cells, which could then lead to genomic instability and spontaneous mutation. Our results suggest that the bcl6 corepressor inactivating mutations exert pro-carcinogenic effects through survival strike, which is only an intermediate process. These findings provide mechanistic insights into the role of the bcl6 corepressor gene in myelodysplastic syndrome.

Safety and efficacy of jaktinib (a novel JAK inhibitor) in patients with myelofibrosis who are intolerant to ruxolitinib: A single-arm, open-label, phase 2, multicenter study.

Although ruxolitinib improves splenomegaly and constitutional symptoms in patients with myelofibrosis (MF), a substantial proportion of patients discontinue ruxolitinib because of intolerance. This phase 2 trial investigated the safety and efficacy of jaktinib, a novel JAK inhibitor in patients with ruxolitinib-intolerant MF. The primary endpoint was the proportion of patients with ≥35% reduction in spleen volume (SVR35) at week 24. The secondary endpoints included change of MF-related symptoms, anemic response, and safety profiles. Between December 18, 2019, and November 24, 2021, 51 patients were enrolled, 45 treated with jaktinib 100 mg bid (100 mg bid group) and six received non-100 mg bid doses (non-100 mg bid group). The SVR35 at week 24 in the 100 mg bid group was 43.2% (19/44, 95% CI 29.7%-57.8%). There were 41.9% (13/31) of transfusion-independent patients with hemoglobin (HGB) ≤100 g/L who had HGB elevation ≥20 g/L within 24 weeks. The proportion of patients with a ≥50% decrease in the total symptom score (TSS 50) at week 24 was 61.8% (21/34). The most commonly reported grade ≥3 treatment-emergent adverse events (TEAEs) in the 100 mg bid group were anemia 31.1%, thrombocytopenia 22.2%, and infectious pneumonia 17.8%. A total of 16 (35.6%) in the 100 mg bid group had serious adverse events, and 4 (8.9%) were considered possibly drug related. These results indicate jaktinib can provide a treatment option for patients with MF who are intolerant to ruxolitinib.

The non-cell-autonomous function of ID1 promotes AML progression via ANGPTL7 from the microenvironment.

The bone marrow microenvironment (BMM) can regulate leukemia stem cells (LSCs) via secreted factors. Increasing evidence suggests that dissecting the mechanisms by which the BMM maintains LSCs may lead to the development of effective therapies for the eradication of leukemia. Inhibitor of DNA binding 1 (ID1), a key transcriptional regulator in LSCs, previously identified by us, controls cytokine production in the BMM, but the role of ID1 in acute myeloid leukemia (AML) BMM remains obscure. Here, we report that ID1 is highly expressed in the BMM of patients with AML, especially in BM mesenchymal stem cells, and that the high expression of ID1 in the AML BMM is induced by BMP6, secreted from AML cells. Knocking out ID1 in mesenchymal cells significantly suppresses the proliferation of cocultured AML cells. Loss of Id1 in the BMM results in impaired AML progression in AML mouse models. Mechanistically, we found that Id1 deficiency significantly reduces SP1 protein levels in mesenchymal cells cocultured with AML cells. Using ID1-interactome analysis, we found that ID1 interacts with RNF4, an E3 ubiquitin ligase, and causes a decrease in SP1 ubiquitination. Disrupting the ID1-RNF4 interaction via truncation in mesenchymal cells significantly reduces SP1 protein levels and delays AML cell proliferation. We identify that the target of Sp1, Angptl7, is the primary differentially expression protein factor in Id1-deficient BM supernatant fluid to regulate AML progression in mice. Our study highlights the critical role of ID1 in the AML BMM and aids the development of therapeutic strategies for AML.

S100a9 deficiency accelerates MDS-associated tumor escape via PD-1/PD-L1 overexpression.

In recent studies, the tolerable safety profile and positive bone marrow (BM) response suggest a beneficial use of anti-PD-1 agents in the treatment of Myelodysplastic Syndromes (MDS), but the underlying mechanism is still unknown. MDS is mainly characterized by ineffective hematopoiesis, which may contribute to inflammatory signaling or immune dysfunction. Our previous studies focused on inflammatory signaling, and the results showed that S100a9 expression was higher in low-risk MDS and lower in high-risk MDS. In this study, we combine the inflammatory signaling and immune dysfunction. SKM-1 cells and K562 cells co-cultured with S100a9 acquire apoptotic features. Moreover, we confirm the inhibitory effect of S100a9 on PD-1/PD-L1. Importantly, PD-1/PD-L1 blockade and S100a9 can both activate the PI3K/AKT/mTOR signaling pathway. The cytotoxicity is higher in lower-risk MDS-lymphocytes than in high-risk MDS-lymphocytes, and S100a9 partially rescues the exhausted cytotoxicity in lymphocytes. Our study demonstrates that S100a9 may inhibit MDS-associated tumor escape via PD-1/PD-L1 blockade through PI3K/AKT/mTOR signaling pathway activation. Our findings indicate the possible mechanisms by which anti-PD-1 agents may contribute to the treatment of MDS. These insights may provide mutation-specific treatment as a supplementary therapy for MDS patients with high-risk mutations, such as TP53, N-RAS or other complex mutations.

The use of carbon monoxide breath test to detect the effect of iron overload on erythrocyte lifespan in MDS.

Objective: To investigate the effect of iron overload (IO) on red blood cell (RBC) lifespan in MDS patients with the use of carbon monoxide breath test. Methods: The red blood cell lifespan of 93 patients with myelodysplastic syndrome (MDS) and 22 healthy volunteers in the control group were measured by alveolar gas carbon monoxide (CO) assay, with the detection of liver iron concentration, iron metabolism index, erythropoietin (EPO) concentration, peripheral blood inflammatory cytokines, etc. The MDS patients were divided into the severe IO group, mild IO group and non IO group according to liver iron concentration. The effect of IO on RBC lifespan was analyzed in MDS patients. Results: The RBC lifespan of MDS patients in the severe IO group was significantly lower than that in the mild IO group (p<0.05), while the RBC life span in the mild IO group was significantly lower than that in the non IO group (p<0.05). The expression of inflammatory cytokines in the severe IO group was significantly higher than that of the mild and non IO groups. After receiving iron removal treatment(ICT), the expression of inflammatory cytokines was decreased significantly, and the RBC lifespan was significantly prolonged (p<0.05).Besides, liver iron concentration was significantly positively correlated with EPO concentration, while EPO concentration was significantly negatively correlated with RBC lifespan, especially in the MDS-RS subgroup. The RBC lifespan in the EPO>1000 group was significantly lower than that in the EPO<1000 group. Conclusion: IO can shorten RBC lifespan in MDS patients, which may be result from the increase of endogenous EPO and the over-expression of inflammatory cytokines. After ICT, the ineffective hematopoiesis caused by increased EPO may reduced and the decrease of inflammatory cytokine may significantly prolong the RBC lifespan in MDS patients.

Decreased FOXO1 Expression Is Correlated with Poor Prognosis in Myelodysplastic Syndromes.

Myelodysplastic syndrome is one of the main hematological malignancies that threaten the health of the elderly. However, biomarkers which predict the progression and prognosis of MDS are still controversial and puzzling. FOXO1 gene plays an important role in a variety of intracellular functions, including tumor suppression and cellular immune regulation. However, there is no research report on the correlation between FOXO1 and the clinical features of MDS including immune environment. In this study, we observed that FOXO1 expression is associated with neutrophil count, blasts, chromosome and different MDS scoring systems. FOXO1 expression is closely related to MDS cell immune polarization, and the increase expression of FOXO1 is significantly related to the amplification of immune cell polarization ratio. In addition, FOXO1 expression is associated with progression-free survival and overall survival in MDS patients. Moreover, in a multivariate model FOXO1 low-expression was an independent predictor of poor survival in MDS. In summary, FOXO1 may play a candidate tumor suppressor in MDS, and FOXO1 is a useful independent prognostic predictor in MDS, and it may provide a candidate target therapy in future.

Targeting UHRF1-SAP30-MXD4 axis for leukemia initiating cell eradication in myeloid leukemia.

Aberrant self-renewal of leukemia initiation cells (LICs) drives aggressive acute myeloid leukemia (AML). Here, we report that UHRF1, an epigenetic regulator that recruits DNMT1 to methylate DNA, is highly expressed in AML and predicts poor prognosis. UHRF1 is required for myeloid leukemogenesis by maintaining self-renewal of LICs. Mechanistically, UHRF1 directly interacts with Sin3A-associated protein 30 (SAP30) through two critical amino acids, G572 and F573 in its SRA domain, to repress gene expression. Depletion of UHRF1 or SAP30 derepresses an important target gene, MXD4, which encodes a MYC antagonist, and leads to suppression of leukemogenesis. Further knockdown of MXD4 can rescue the leukemogenesis by activating the MYC pathway. Lastly, we identified a UHRF1 inhibitor, UF146, and demonstrated its significant therapeutic efficacy in the myeloid leukemia PDX model. Taken together, our study reveals the mechanisms for altered epigenetic programs in AML and provides a promising targeted therapeutic strategy against AML.

Comparison of efficacy and safety of ripertamab (SCT400) versus rituximab (Mabthera® ) in combination with CHOP in patients with previously untreated CD20-positive diffuse large B-cell lymphoma: A randomized, single-blind, phase III clinical trial.

This study compared the efficacy, safety and immunogenicity of ripertamab (SCT400) and rituximab (Mabthera® ) combined with CHOP as the first-line treatment for Chinese patients with CD20-positive diffuse large B cell lymphoma (DLBCL). This is a randomized, patient-blind, multicenter, active-control, non-inferiority study with parallel design. Patients were randomly (2:1) to receive ripertamab combined with CHOP (S-CHOP) or rituximab (Mabthera® ) combined with CHOP (R-CHOP) for up to 6 cycles. The primary endpoint was the Independent Review Committee (IRC) assessed objective response rate (ORR) in full analysis set (FAS) and the per protocol set (PPS). A total of 364 patients (243 in the S-CHOP and 121 in the R-CHOP groups) were enrolled in this study. In FAS, IRC-assessed ORRs were 93.8% (95% confidence interval (CI) 90.0%, 96.5%) and 94.2% (95% CI: 88.4%, 97.6%) in the S-CHOP and R-CHOP groups (p = 0.9633), respectively. The ORR difference between the two groups -0.4% (95% CI: -5.5%, 4.8%) met the pre-specified non-inferiority margin of -12%. There were no significant differences between the S-CHOP and R-CHOP groups in 1-year progression-free survival rates (81.1% vs. 83.2%, p = 0.8283), 1 year event-free survival rates (56.2% vs. 58.1%, p = 0.8005), and 3-year overall survival rates (81.0% vs. 82.8%, p = 0.7183). The results in PPS were consistent with those in FAS. The rates of treatment-emergent adverse events (TEAEs) and ≥ grade 3 TEAEs were 97.9% and 99.2%, 85.2% and 86.0% in the S-CHOP and R-CHOP groups, respectively in safety set. The percentage of anti-drug antibodies positive patients in the S-CHOP group was numerically lower than the R-CHOP group (10.9% vs. 16.0%). This study demonstrated that S-CHOP was not inferior to R-CHOP in the first-line treatment of Chinese patients with CD20-positive DLBCL in efficacy, safety and immunogenecity. S-CHOP could be an alternative first-line standard treatment regimen for this patient population.

Bone Marrow Fibrosis at Diagnosis and during the Course of Disease Is Associated with TP53 Mutations and Adverse Prognosis in Primary Myelodysplastic Syndrome.

The prognostic significance of bone marrow fibrosis (MF) grade in patients with myelodysplastic syndrome (MDS) is still debated and the molecular changes remain unclear. In our large cohort, a normal reticulum was found in 211 (25.9%) patients, whereas MF1, MF2 and MF3 were detected in 478 (58.7%), 90 (11.1%) and 35 (4.3%) patients at initial diagnosis, respectively. Patients with MF often correlated with some poor prognostic characteristics, including older age, anemia, unfavorable karyotype, higher BM blast and a higher IPSS-R category. For the entire cohort, the median OS was not reached, 30, 16 and 15 months for patients with MF 0, 1, 2 and 3, respectively. After adjusting for IPSS-R, the hazard ratio for mortality was 1.56 (95% CI, 1.18-2.06) for patients with MF1, 2.29 (95% CI, 1.61-3.27) for patients with MF2 and 2.75 (95% CI, 1.69-4.49) for patients with MF3 compared with those with MF0. The mutational landscape of 370 patients showed that TP53, U2AF1 and KMT2D mutations were more frequent in patients with MF2-3. In addition, of the 408 patients with MF0-1, 62 patients (15.1%) progressed to MF2-3 during the follow-up interval. The clinical features, mutation landscape and prognosis of patients with progressed fibrosis were similar to those of patients with MF2-3 at diagnosis. We concluded that BM fibrosis (MF1, 2 and 3) was an adverse prognosis feature in primary MDS and correlated with TP53 mutations both at the time of initial diagnosis and during the course of the disease. Therefore, BM fibrosis should be included in the revised prognostic scoring system and carefully considered in treatment selection.

Selinexor plus low-dose dexamethasone in Chinese patients with relapsed/refractory multiple myeloma previously treated with an immunomodulatory agent and a proteasome inhibitor (MARCH): a phase II, single-arm study.

BACKGROUND: Selinexor 80 mg combined with low-dose dexamethasone (Sd) demonstrated significant clinical benefit in patients with relapsed/refractory multiple myeloma (RRMM) who had disease refractory to a proteasome inhibitor (PI), an immunomodulator (IMiD), and an anti-CD38 monoclonal antibody based on a global phase II STORM study. The present study, MARCH, addresses China regulatory needs to further validate the data from STORM in Chinese patients with RRMM. METHODS: The MARCH study was conducted at 17 sites in China, where eligible Chinese RRMM patients who had disease refractory to PI and IMiD were enrolled. Selinexor 80 mg combined with dexamethasone 20 mg was administered orally on day 1 and day 3 of each week in 4-week cycles. The primary endpoint was the overall response rate (ORR) per an independent review committee, with the null hypothesis of ≤15%. Patients who received at least 1 dose of study treatment were included in the safety population. The pharmacokinetic (PK) profile was characterized by parameter and ethnicity sensitivity analyses. RESULTS: A total of 82 patients with RRMM were enrolled in the study, with a median age of 60 years. Of the 82 patients, 55 patients (67.1%) had high-risk cytogenetic abnormalities, defined as one or more of del 17p13, t(4;14), t(14;16), or 1q amplification identified by fluorescence in situ hybridization (FISH); 18 patients (22.0%) had abnormal renal function. Enrolled patients were heavily pre-treated with a median prior regimen number of 5. All 82 patients (100%) were refractory to both PI and IMiD, including 20 patients (24.4%) categorized as triple-class refractory population (refractory to PI, IMiD, and daratumumab). Ten patients (12.2%) had undergone CAR-T therapy. ORR was 29.3% (95% CI 19.7, 40.4) with a median DOR of 4.7 months. The median PFS and OS were 3.7 and 13.2 months, respectively. ORR was 25.0% (95% CI 8.7, 49.1) in the triple-class refractory population. Efficacy was consistent across various subgroups. The most frequent grade 3/4 adverse events (AEs) included anemia (57.3%), thrombocytopenia (51.2%), lymphopenia (42.7%), neutropenia (40.2%), hyponatremia (29.3%), and lung infection (26.8%). Serious AEs were reported in 54.9% of patients. No significant drug accumulation was shown following multiple administrations. No human PK ethnicity difference was identified between Chinese and western patients. CONCLUSIONS: With an encouraging ORR, the MARCH study has demonstrated that selinexor combined with low-dose dexamethasone (Sd) delivers meaningful clinical benefit to Chinese patients with RRMM, including triple-class refractory patients. AEs were expected and manageable with supportive care and dose modification. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03944057 (May 09, 2019); Chinadrugtrials.org.cn , CTR20190858 (June 05, 2019).

Aryl hydrocarbon receptor signaling pathway plays important roles in the proliferative and metabolic properties of bone marrow mesenchymal stromal cells.

Bone marrow mesenchymal stromal cells (BMMSCs) are widely sourced and easily amplified in vitro; thus, they have a great potential in the treatment of hemopathies. Recent findings suggested that BMMSCs express the aryl hydrocarbon receptor (AHR). However, few studies have reported on the regulation of proliferative behaviors and metabolism by AHR in BMMSCs. In the present study, we found that activating AHR reduced the proliferation of BMMSCs and enhanced their mitochondrial function, whereas inhibiting AHR exerted the opposite effects. This study may provide the basis for further unveiling the molecular mechanisms and therapeutic potential of AHR in BMMSCs.

[Research Progress in the Role of Tim3/galectin-9 in Hematological Malignancy--Review].

The incidence of hematological malignant tumor is increasing year by year, and seriously affecting the human health. In addition to the traditional radiation and chemotherapy, immunotherapy has achieved a certain effect in the treatment of blood tumor, but it is limited by exhaustion of CD8+ T cell. The exhaustion of CD8+ T cells is mainly related to the activation of some immune checkpoint inhibitors, such as (Tim3), programmed death 1 (PD-1), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), etc. Among them, Tim3 is getting more and more attention. The combination of Tim3 and its ligand galectin-9 produced a strong cellular immunosuppressive effect. Tim3 has been proved to be associated with CD8+ T cell exhaustion in many tumors. In this review, the application of Tim3/galectin-9 in hematologic tumors is briefly summarized so as to provide theoretical basis for clinical diagnosis and treatment of these diseases.