The efficacy and safety of fexuprazan in treating erosive esophagitis: a phase III, randomized, double-blind, multicenter study

BACKGROUND AND AIM

Fexuprazan is a novel potassium-competitive acid blocker (P-CAB). This study aimed to explore the noninferior efficacy and safety of fexuprazan to esomeprazole in treating erosive esophagitis (EE).

METHODS

This was a phase III, randomized, double-blind multicenter study. Patients with endoscopically confirmed EE were randomized to receive fexuprazan 40 mg or esomeprazole 40 mg once a daily for 4-8 weeks. The healing rates of EE, symptom response, GERD-health-related quality life (GERD-HRQL), and treatment-emergent adverse events (TEAEs) were compared between fexuprazan group and esomeprazole group.

RESULTS

A total of 332 subjects were included in full analysis set (FAS) and 311 in per-protocol set (PPS). The healing rates of fexuprazan and esomeprazole groups at 8 weeks were 88.5% (146/165) and 89.0% (145/163), respectively, in FAS and 97.3% (145/149) and 97.9% (143/146), respectively, in PPS. Noninferiority of fexuprazan compared with esomeprazole according to EE healing rates at 8 weeks was demonstrated in both FAS and PPS analysis. No significant difference was found between groups in EE healing rates at 4 weeks, symptom responses, and changes of GERD-HRQL. The incidence of drug-related AEs was 19.4% (32/165) in fexuprazan arm and 19.6% (32/163) in esomeprazole arm.

CONCLUSION

This study demonstrated noninferior efficacy of fexuprazan to esomeprazole in treating EE. The incidence of TEAEs was similar between fexuprazan and esomeprazole. Trial registration number NCT05813561.

Predictive effect of net water uptake on futile recanalisation in patients with acute large-vessel occlusion stroke

AIM

To determine whether net water uptake (NWU) based on automated software evaluation could predict futile recanalisation in patients with acute anterior circulation large-vessel occlusion (LVO).

MATERIALS AND METHODS

Patients with acute anterior circulation LVO undergoing mechanical thrombectomy in Jinling Hospital were evaluated retrospectively. NWU and other baseline data were evaluated by performing univariate and multivariate analyses. The primary endpoint was 90-day modified Rankin scale score ≥3. A nomogram to predict poor clinical outcomes was developed based on multivariate logistic regression analysis.

RESULTS

Overall, 135 patients who underwent thrombectomy with a TICI grade ≥2b were enrolled. In multivariate logistic regression analysis, the following factors were identified as independent predictors of futile recanalisation: age (odds ratio [OR]: 1.055, 95 % confidence interval [CI]: 1.004-1.110, p=0.035), female (OR: 0.289, 95 % CI: 0.098-0.850, p=0.024), hypertension (OR: 3.182, 95 % CI: 1.160-8.728, p=0.025), high blood glucose level (OR: 1.36, 95 % CI: 1.087-1.701, p=0.007), admission National Institutes of Health Stroke Scale score (OR: 1.082, 95 % CI: 1.003-1.168, p=0.043), and NWU (OR: 1.312, 95 % CI: 1.038-1.659, p=0.023).

CONCLUSIONS

NWU based on Alberta Stroke Program Early Computed Tomography (CT) Score (ASPECTS) could be used to predict the occurrence of futile recanalisation in patients with acute anterior circulation LVO ischaemic stroke.

MUC20 regulated by extrachromosomal circular DNA attenuates proteasome inhibitor resistance of multiple myeloma by modulating cuproptosis

BACKGROUND

Proteasome inhibitors (PIs) are one of the most important classes of drugs for the treatment of multiple myeloma (MM). However, almost all patients with MM develop PI resistance, resulting in therapeutic failure. Therefore, the mechanisms underlying PI resistance in MM require further investigation.

METHODS

We used several MM cell lines to establish PI-resistant MM cell lines. We performed RNA microarray and EccDNA-seq in MM cell lines and collected human primary MM samples to explore gene profiles. We evaluated the effect of MUC20 on cuproptosis of PI-resistant MM cells using Co-immunoprecipitation (Co-IP), Seahorse bioenergetic profiling and in vivo assay.

RESULTS

This study revealed that the downregulation of Mucin 20 (MUC20) could predict PI sensitivity and outcomes in MM patients. Besides, MUC20 attenuated PI resistance in MM cells by inducing cuproptosis via the inhibition of cyclin-dependent kinase inhibitor 2 A expression (CDKN2A), which was achieved by hindering MET proto-oncogene, receptor tyrosine kinase (MET) activation. Moreover, MUC20 suppressed MET activation by repressing insulin-like growth factor receptor-1 (IGF-1R) lactylation in PI-resistant MM cells. This study is the first to perform extrachromosomal circular DNA (eccDNA) sequencing for MM, and it revealed that eccDNA induced PI resistance by amplifying kinesin family member 3 C (KIF3C) to reduce MUC20 expression in MM.

CONCLUSION

Our findings indicated that MUC20 regulated by eccDNA alleviates PI resistance of MM by modulating cuproptosis, which would provide novel strategies for the treatment of PI-resistant MM.

Application of pyroptosis score in the treatment and prognosis evaluation of gastric cancer

Pyroptosis is a kind of proinflammatory programmed cell death mediated by inflammasome. It affects the occurrence and development of gastric cancer through different ways, showing dual effects. On the one hand, inflammasome-mediated inflammatory response is highly likely to participate in the formation and development of early tumors; on the other hand, drugs can inhibit the deterioration process of tumor proliferation, invasion and metastasis through activating the pathways of inflammasome and pyroptosis. Recently, many agents based on pyroptosis have been found to inhibit gastric cancer by promoting the secondary pyroptosis pathway, regulating NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome and inhibiting caspase-1. The establishment of cell pyrodeath models can predict the prognosis of gastric cancer patients. Most of the models show that gastric cancer patients with high pyroptosis level have better prognosis and longer overall survival. Pyroptosis scores can also be used to predict the response of gastric cancer patients to immunotherapy and to screen potential anti-gastric cancer drugs. Therefore, in-depth understanding of the potential mechanism of pyroptosis affecting the progression of gastric cancer and the role of pyroptosis score in the treatment and prognosis assessment of gastric cancer will be helpful to find a new and effective method for the treatment of gastric cancer.

Patient Journey Toward a Diagnosis of Light Chain Amyloidosis in a National Sample: Cross-Sectional Web-Based Study

BACKGROUND

Systemic light chain (AL) amyloidosis is a rare and multisystem disease associated with increased morbidity and a poor prognosis. Delayed diagnoses are common due to the heterogeneity of the symptoms. However, real-world insights from Chinese patients with AL amyloidosis have not been investigated.

OBJECTIVE

This study aimed to describe the journey to an AL amyloidosis diagnosis and to build an in-depth understanding of the diagnostic process from the perspective of both clinicians and patients to obtain a correct and timely diagnosis.

METHODS

Publicly available disease-related content from social media platforms between January 2008 and April 2021 was searched. After performing data collection steps with a machine model, a series of disease-related posts were extracted. Natural language processing was used to identify the relevance of variables, followed by further manual evaluation and analysis.

RESULTS

A total of 2204 valid posts related to AL amyloidosis were included in this study, of which 1968 were posted on haodf.com. Of these posts, 1284 were posted by men (median age 57, IQR 46-67 years); 1459 posts mentioned renal-related symptoms, followed by heart (n=833), liver (n=491), and stomach (n=368) symptoms. Furthermore, 1502 posts mentioned symptoms related to 2 or more organs. Symptoms for AL amyloidosis most frequently mentioned by suspected patients were nonspecific weakness (n=252), edema (n=196), hypertrophy (n=168), and swelling (n=140). Multiple physician visits were common, and nephrologists (n=265) and hematologists (n=214) were the most frequently visited specialists by suspected patients for initial consultation. Additionally, interhospital referrals were also commonly seen, centralizing in tertiary hospitals.

CONCLUSIONS

Chinese patients with AL amyloidosis experienced referrals during their journey toward accurate diagnosis. Increasing awareness of the disease and early referral to a specialized center with expertise may reduce delayed diagnosis and improve patient management.

Outcome and characteristics of nonsecretory multiple myeloma compared with secretory multiple myeloma: a retrospective multicenter study from China

BACKGROUND

Nonsecretory multiple myeloma (NSMM) is a rare type of multiple myeloma (MM). Few studies have described the clinical features and outcomes of NSMM in novel agents. Additionally, the prognostic characteristics have remained controversial in recent years.

PURPOSE

To investigate the clinical and prognostic features of NSMM and explore the prognostic value of involved free light chain (FLC) levels in NSMM patients in the Chinese population.

METHODS

We retrospectively enrolled 176 newly diagnosed NSMM cases between January 2005 and December 2021 from 19 clinical centers in China. The control group was selected using a 1:4 propensity score matching technique of newly diagnosed secretory MM, with age, sex and diagnosis time as the matching variables.

RESULTS

The median age of NSMM patients was 60 years, and 22.6% of patients were classified as ISS stage 3. The ORR of the NSMM patients was 87.4%, and the CR was 65.8%. Compared to the matched secretory MM patients, more NSMM patients achieved CR after first-line treatment (65.8% vs. 36%, p = 0.000). The ORR of first-line treatment was not significantly different between NSMM and secretory MM (89.45% vs. 84.7%, p = 0.196). The first-line PFS was 27.5 m and 23 m (p = 0.063), and the median OS was 81 m and 70 months (p = 0.401). However, for CR-achieved NSMM and CR-not-achieved NSMM patients, the median PFS was 37 m vs. 16 m (p = 0.021), while the median OS showed no difference (107 m vs. 87 m, p = 0.290). In multivariate analysis, the significant factors for PFS were age ≥ 65 and ISS-3. ISS-3 was the only independent prognostic factor of OS. The iFLC ≥ 50 mg/L group had a high ORR of 97.3%, and the median PFS and OS were 48 m and NR, respectively. Compared to the matched secretory MM, the iFLC ≥ 50 mg/L group also showed more CR and longer OS (NR vs. 70 m, p = 0.006) and PFS (48 m vs. 23 m, p = 0.003).

CONCLUSIONS

Our results revealed that Chinese NSMM patients are younger and have a higher CR but not superior survival. The subgroup of NSMM patients with iFLC ≥ 50 mg/L had better outcomes than secretory MM.

SF3B1 mutation and ATM deletion codrive leukemogenesis via centromeric R-loop dysregulation

RNA splicing factor SF3B1 is recurrently mutated in various cancers, particularly in hematologic malignancies. We previously reported that coexpression of Sf3b1 mutation and Atm deletion in B cells, but not either lesion alone, leads to the onset of chronic lymphocytic leukemia (CLL) with CLL cells harboring chromosome amplification. However, the exact role of Sf3b1 mutation and Atm deletion in chromosomal instability (CIN) remains unclear. Here, we demonstrated that SF3B1 mutation promotes centromeric R-loop (cen-R-loop) accumulation, leading to increased chromosome oscillation, impaired chromosome segregation, altered spindle architecture, and aneuploidy, which could be alleviated by removal of cen-R-loop and exaggerated by deletion of ATM. Aberrant splicing of key genes involved in R-loop processing underlay augmentation of cen-R-loop, as overexpression of the normal isoform, but not the altered form, mitigated mitotic stress in SF3B1-mutant cells. Our study identifies a critical role of splice variants in linking RNA splicing dysregulation and CIN and highlights cen-R-loop augmentation as a key mechanism for leukemogenesis.

METTL3-Mediated m6A Modification Controls Splicing Factor Abundance and Contributes to Aggressive CLL

RNA splicing dysregulation underlies the onset and progression of cancers. In chronic lymphocytic leukemia (CLL), spliceosome mutations leading to aberrant splicing occur in ∼20% of patients. However, the mechanism for splicing defects in spliceosome-unmutated CLL cases remains elusive. Through an integrative transcriptomic and proteomic analysis, we discover that proteins involved in RNA splicing are posttranscriptionally upregulated in CLL cells, resulting in splicing dysregulation. The abundance of splicing complexes is an independent risk factor for poor prognosis. Moreover, increased splicing factor expression is highly correlated with the abundance of METTL3, an RNA methyltransferase that deposits N6-methyladenosine (m6A) on mRNA. METTL3 is essential for cell growth in vitro and in vivo and controls splicing factor protein expression in a methyltransferase-dependent manner through m6A modification-mediated ribosome recycling and decoding. Our results uncover METTL3-mediated m6A modification as a novel regulatory axis in driving splicing dysregulation and contributing to aggressive CLL.

SIGNIFICANCE

METTL3 controls widespread splicing factor abundance via translational control of m6A-modified mRNA, contributes to RNA splicing dysregulation and disease progression in CLL, and serves as a potential therapeutic target in aggressive CLL. See related commentary by Janin and Esteller, p. 176. This article is highlighted in the In This Issue feature, p. 171.

Abstract 3482: METTL3-mediated m6A modification controls splicing factor abundance and contributes to CLL progression

RNA splicing dysregulation is a hallmark of cancers and underlies the onset and progression of diseases. Chronic lymphocytic leukemia (CLL) is one of the most common adult leukemia in western countries. Spliceosome mutations occur in ~20% of patients. However, the mechanism for splicing defects in spliceosome unmutated CLL cases remains elusive. Through an integrative transcriptomic and proteomic analysis of primary CLL samples, we discovered proteins involved in RNA splicing are post-transcriptionally upregulated. Coupled with clinical annotation, we found spliceosome protein abundance is an independent risk factor and associated with poor prognosis. Splice variants found in CLL are highly overlapped with those driven by high spliceosome abundance but not splicing factor mutations, indicating high spliceosome abundance contributes to genetic lesion-independent splicing defects. To identify potential regulators for spliceosome, we proteome-widely analyzed the proteins that highly correlated with splicing factors expression. Analysis of 113 CLL samples has consistently identified METTL3 upregulation with positive correlation with 77.6% of detected splicing factors. METTL3 is an RNA methyltransferase that modifies N6-methyladenosine (m6A) on mRNA and regulates the translation of m6A-installed transcripts. m6A level on mRNA is increased in CLL cells with differential m6A highly enriched on splicing related transcripts. Moreover, high METTL3 expression in CLL is also associated with poor clinical outcomes. These results suggested that METTL3 translationally controls splicing factors through m6A and plays a role in CLL progression. Toward this end, we demonstrated that METTL3 is essential for CLL growth in both in vitro and in vivo studies. Knock out (KO) and pharmaceutical inhibition of METTL3 decreased cell growth and splicing factor expression. Overexpression of wildtype but not catalytic mutant METTL3 restored both defects in METTL3 KO cells, indicating that the regulation of splicing factor is m6A-dependent. To dissect the underlying mechanism, we performed an integrated Ribo-seq, RNA-seq, and MeRIP-seq on CLL cells with or without METTL3. KO of METTL3 decreased overall translation efficiency (TE) with RNA splicing as the most significantly affected pathway. Splicing factors with reduced TE displayed either hypo-m6A at stop codon region or hyper-m6A at CDS regions upon METTL3 KO, as direct or indirect targets of METTL3. Moreover, we found that m6A at stop codon and CDS regions regulates splicing factor translation via ribosome recycling and ribosome pausing, respectively. Taken together, our results uncovered a novel regulatory axis for METTL3 that controls splicing factor translation and contributes to CLL progression. Our study highlights a post-transcriptional layer of m6A modification as a major contributor to genetic lesion-independent splicing defects in CLL.

Citation Format: Yiming Wu, Meiling Jin, Mike Fernandez, Kevyn Hart, Aijun Liao, Stacey M. Fernandes, Tinisha McDonald, Zhenhua Chen, Daniel Röth, Lucy Ghoda, Guido Marcucci, Markus Kalkum, Raju K. Pillai, Alexey V. Danilov, Jianjun Chen, Jennifer R. Brown, Steven T. Rosen, Tanya Siddiqi, Lili Wang. METTL3-mediated m6A modification controls splicing factor abundance and contributes to CLL progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3482.

RASSF1A inhibits epithelial-mesenchymal transition of gastric cancer cells by downregulating P-JNK

Gastric cancer (GC) is one of the most common gastrointestinal tumors. In this study, we assessed the biological role of Ras association domain family 1 isoform A (RASSF1A) in GC cells. Expressions of RASSF1A and the relationship of RASSF1A with epithelial-mesenchymal transformation (EMT)-related proteins were assessed in five cell lines using Western blot. GC cells with RASSF1A overexpression were used to study sensitivity to cisplatin, migration, invasion, and the expression of EMT-associated biomarkers. GC cells showed profound downregulation of RASSF1A expression compared with normal human gastric mucosal cells. High RASSF1A expression was associated with increased overall survival. Overexpression of RASSF1A regulates GC cells activity and the expression of EMT-associated biomarkers. RASSF1A regulates E-cadherin and Vimentin through P-JNK pathway. Our results revealed that RASSF1A can inhibit the proliferation, migration, and invasion of GC cells via E-cadherin. Our study provides insights for further research on GC.

Lenalidomide or bortezomib as maintenance treatment remedy the inferior impact of high-risk cytogenetic abnormalities in non-transplant patients with newly diagnosed multiple myeloma: a real-world multi-centered study in China

Maintenance treatment is a pivotal part in the whole process management of multiple myeloma (MM), which further deepens response and improves survival. However, evidence of maintenance in non-transplant MM patients is inadequate in real-world practice. Here, we retrospectively analyzed the efficacy and survival of 375 non-transplant MM patients from 11 centers between 2010 and 2021 in north China. After a median of seven cycles of front-line regimens, there were 141, 79, and 155 patients receiving lenalidomide maintenance (L-MT), bortezomib maintenance (B-MT), or thalidomide maintenance (T-MT), respectively. Patients on L-MT and B-MT had significantly greater proportions of high-risk cytogenetic abnormalities (HRCAs) detected by fluorescence in situ hybridization (FISH), which was defined as 1q21 gain, 17p deletion, adverse immunoglobulin heavy chain (IgH) translocations. Although the progression-free survival (PFS) and overall survival (OS) were comparable among the three groups, L-MT and B-MT remedied the negative impact of HRCAs on survival (PFS of patients with HRCAs vs. patients without HRCAs: L-MT, 26.9 vs. 39.2 months, p=0.19; B-MT, 20.0 vs. 29.7 months, p=0.36; OS not reached in all groups). Patients with HRCAs in the T-MT group presented inferior clinical outcomes compared to standard-risk patients (PFS, 12.1 vs. 22.8 months, p=0.02, HR=1.8, 95% CI 1.0-3.4; OS, 54.9 months vs. NR, p<0.001, HR=3.2, 95% CI 1.5-7.0). Achieving complete response (CR) after induction therapy led to superior PFS compared to other degrees of response, regardless of maintenance medication. Furthermore, maintenance duration over 24 months correlated with favorable survival. Due to the large gap of transplant eligibility in China, optimizing maintenance therapy is important for non-transplant MM patients. In this real-world multi-centered study, our findings suggest that clinicians prefer to prescribe lenalidomide or bortezomib as maintenance therapy in high-risk settings, which are superior to thalidomide in non-transplant MM patients. Achievement of CR and maintenance duration over 2 years are positive factors that influence survival.

Aberrant SPOP-CHAF1A ubiquitination axis triggers tumor autophagy that endows a therapeutical vulnerability in diffuse large B cell lymphoma

Purpose

Aberrant epigenetic changes, like DNA methylation, histone modifications, or ubiquitination, could trigger metabolic disorders in human cancer cells. This study planed to uncover the biological roles of epigenetic SPOP/CHAF1A axis in modulating tumor autophagy during Diffuse large B-cell lymphoma (DLBCL) tumorigenesis.

Materials and methods

The Immunohistochemistry (IHC) was performed to assess the CHAF1A expressions. The expression data of CHAF1A was derived from The Cancer Genome Atlas (TCGA), GSE32918 and GSE83632 datasets. Bioinformatic assays contain differential analysis, functional enrichment analysis and Kaplan–Meier survival curve analysis. The colony generation assay, Transwell assay and CCK-8 assays were conducted for the in vitro assays. The in vivo ubiquitination assays were used to assess regulations of SPOP on CHAF1A. The Chromatin immunoprecipitation (ChIP) assays were used to uncover epigenetic regulations of CHAF1A on TFEB. The relevant DLBCL cells were subcutaneously injected to SCID beige mice to establish the xenograft models.

Results

Bioinformatic results revealed that CHAF1A expressed highly in DLBCL that were validated in patients samples. Patients with high CHAF1A suffered from inferior prognosis with shorter survival months relative to those with low CHAF1A. High CHAF1A enhanced DLBCL aggressiveness, including cell proliferation, migration and in vivo growth. Mechanistically, E3 ubiquitin ligase SPOP binds to and induces the degradative ubiquitination of CHAF1A via recognizing a consensus SPOP-binding motif in CHAF1A. SPOP is down-regulated in DLBCL and habours two DLBCL-associated mutations. Deficient SPOP leads to accumulated CHAF1A proteins that promote malignant features of DLBCL. Subsequently, ChIP-qPCR assay revealed that CHAF1A directly binds to TFEB promoters to activate the expressions. High CHAF1A could enhance the transcriptional activity of TFEB and downstream genes. The SPOP/CHAF1A axis modulates TFEB-dependent transactivation to regulate the lysosomal biogenesis and autophagy. The in vivo models suggested that TFEB inhibition is effective to suppress growth of SPOP-deficient DLBCLs.

Conclusions

CHAF1A is aberrantly elevated in SPOP-deficient DLBCL. The in‐depth mechanism understanding of SPOP/CHAF1A/TFEB axis endows novel targets for DLBCL treatment.

The efficacy and safety of keverprazan, a novel potassium-competitive acid blocker, in treating erosive oesophagitis: a phase III, randomised, double-blind multicentre study

BACKGROUND

Keverprazan is a novel potassium-competitive acid blocker (P-CAB) with a strong acid-suppressive capacity that may provide clinical benefit in acid-related diseases.

AIMS

This study aimed to explore the non-inferior efficacy and safety of keverprazan to lansoprazole in treating erosive oesophagitis (EO).

METHODS

This was a phase III, randomised, double-blind multicentre study. Patients were randomised to receive keverprazan 20 mg once daily or lansoprazole 30 mg once daily for 4-8 weeks. EO healing rates and adverse events (AEs) were compared between the keverprazan group and the lansoprazole group.

RESULTS

A total of 238 patients comprised the full analysis set (FAS) while 221 patients comprised the per-protocol set (PPS). For FAS analysis, the EO healing rates at week 8 were 95.8% (114/119) and 89.9% (107/119) for keverprazan and lansoprazole respectively. For PPS analysis, the EO healing rates at week 8 were 99.1% (110/111) and 92.7% (102/110) for keverprazan and lansoprazole respectively. Non-inferiority of keverprazan compared with lansoprazole according to EO healing rates at 8 weeks was demonstrated in both FAS (difference: 5.8% [95% CI: -0.6% to 12.3%]; p = 0.081) and PPS (difference: 6.1% [95% CI: 1.1%-11.2%]; p = 0.018) analysis. Drug-related AEs were reported in 34.5% (41/119) patients of the keverprazan group and 25.2% (30/119) patients of the lansoprazole group with no significant difference (p = 0.156). No severe AE happened in the keverprazan group.

CONCLUSIONS

This study demonstrated the non-inferior efficacy of keverprazan to lansoprazole in treating EO. The incidences of drug-related AEs were comparable between keverprazan and lansoprazole.

CASC7: a LncRNA with potential clinical application

AIM

To explore the novel lncRNA CASC7 and its potential clinical applications.Long non-coding RNAs (IncRNAs) are defined as non-coding genes with a length exceeding 200 nt. As transcripts of RNA polymerase Il, they have limited coding potential due to the lack of an open reading frame in the gene segment. Research has confirmed that lncRNAs are important biological factors that regulate many life processes in the human body through different mechanisms. This work focused on Cancer Susceptibility Candidate 7 (CASC7), a lncRNA with nuclear and cytoplasmic localization. Publicly available databases show that CASC7 is differentially expressed in human organs as well as in tumor tissues. A study confirmed that CASC7 is abnormally expressed in colorectal cancer, glioma, breast cancer, non-small cell lung cancer and thyroid cancer. In male infertility, asthma and heart failure, it may also be a potential therapeutic target and promising biomarker. CASC7 mainly plays a biological effect through direct or indirect effects of promoting or inhibiting the expression of related genes. Currently, only few studies have assessed CASC7, and its mechanisms are not clear. The main purpose of this review was to examine CASC7 and its possible molecular mechanisms and clinical significance in cancer.

CONCLUSION

We reviewed the recent research progress of CASC7 and its potential as a diagnostic marker and therapeutic target, and provide an outlook on its future application in terms of mechanism.Key points:CASC7 is a novel lncRNA, for which there are few reports.Aberrant expression of CASC7 may be associated with the emergence and treatment of many clinical diseases, including malignancy.

Short-chain fatty acids in patients with schizophrenia and ultra-high risk population

BACKGROUND

Individuals who experience the prodromal phase of schizophrenia (SCZ), a common and complex psychiatric disorder, are referred to as ultra-high-risk (UHR) individuals. Short-chain fatty acid (SCFA) is imperative in the microbiota-gut-brain axis and brain function. Accumulating amount of evidence shows the connections between psychiatric disorders and SCFAs. This study aims to explore the underlying roles SCFAs play in SCZ by investigating the association of alterations in SCFAs concentrations with common cognitive functions in both the SCZ and UHR populations.

METHODS

The study recruited 59 SCZ patients (including 15 participants converted from the UHR group), 51 UHR participants, and 40 healthy controls (HC) within a complete follow-up of 2 years. Results of cognitive functions, which were assessed by utilizing HVLT-R and TMT, and serum concentrations of SCFAs were obtained for all participants and for UHR individuals at the time of their conversion to SCZ.

RESULTS

Fifteen UHR participants converted to SCZ within a 2-year follow-up. Valeric acid concentration levels were lower in both the baseline of UHR individuals whom later converted to SCZ (p = 0.046) and SCZ patients (p = 0.036) than the HC group. Additionally, there were lower concentrations of caproic acid in the baseline of UHR individuals whom later transitioned to SCZ (p = 0.019) and the UHR group (p = 0.016) than the HC group. Furthermore, the caproic acid levels in the UHR group are significantly positively correlated with immediate memory (r = 0.355, p = 0.011) and negatively correlated with TMT-B (r = -0.366, p = 0.009). Significant differences in levels of acetic acid, butyric acid and isovaleric acid were absent among the three groups and in UHR individuals before and after transition to SCZ.

CONCLUSION

Our study suggests that alterations in concentrations of SCFAs may be associated with the pathogenesis and the cognitive impairment of schizophrenia. Further researches are warranted to explore this association. The clinical implications of our findings were discussed.

Nomogram Model for Dynamic and Individual Prediction of Cardiac Response and Survival for Light Chain Amyloidosis in 737 Patients With Cardiac Involvement

Objective

Light chain amyloidosis (AL) with cardiac involvement is associated with poor prognosis. The existing prognostic assessment system does not consider treatment-related factors, and there is currently no effective system for predicting the response. The purpose of this study was to build an individualized, dynamic assessment model for cardiac response and overall survival (OS) for AL patients with cardiac involvement.

Methods

The records of 737 AL patients with cardiac involvement were collected through cooperation with 18 hospitals in the Chinese Registration Network for Light-chain Amyloidosis (CRENLA). We used univariate and multivariate analyses to evaluate the prognostic factors for OS and cardiac response. Then, two nomogram models were developed to predict OS and cardiac response in AL patients with cardiac involvement.

Results

A nomogram including four independent factors from the multivariate Cox proportional hazards analysis—Mayo staging, courses of treatment, hematologic response, and cardiac response—was constructed to calculate the possibility of achieving survival by adding all the points associated with four variables. The higher the score, the more likely death would occur. The other nomogram model included the courses of treatment, hematological response, and different treatment regimens, and was correlated with cardiac response. The higher the score, the more likely a cardiac response would occur.

Conclusion

In conclusion, based on the large Chinese cohort of patients with AL and cardiac involvement, we identified nomogram models to predict cardiac response and OS. These models are more individualized and dynamic, and therefore, they have important clinical application value.

Case Report: Management of Primary Tracheobronchial Light Chain Amyloidosis in a Patient With Biclonal Gammopathy Using a Systemic Bortezomib-Based Regimen

Primary tracheobronchial light chain (AL) amyloidosis is a rare and heterogeneous disease characterized by the buildup of amyloid deposits in the airway mucosa. Although its treatment remains challenging, the current view is that the localized form can be treated conservatively due to its slow progression. While radiotherapy has proven effective in treating localized form of the disease, some patients do not respond to local treatment and continue to experience poor quality of life, highlighting the need to explore additional treatment strategies. In this report, we discuss a case of primary tracheobronchial AL amyloidosis with biclonal gammopathy (IgA κ and IgG κ) in a 46-year-old man who was transferred to our hospital due to dyspnea progression over the preceding 3 years. Chest computed tomography revealed irregular tracheobronchial stenosis with wall thickening, and histological examination of the bronchial biopsies confirmed the diagnosis of endobronchial AL amyloidosis. Owing to the poor effect of radiation therapy and treatments for improving airway patency, he was treated with a systemic chemotherapy regimen [cyclophosphamide-bortezomib-dexamethasone (CyBorD)]. We observed substantial improvements in his dyspnea, highlighting the potential of systemic therapy to improve quality of life of patients with tracheobronchial AL amyloidosis. However, the long-term pathological changes associated with local bronchial lesions require further investigation.

Dual Growth Factor (rhTPO + G-CSF) and Chemotherapy Combination Regimen for Elderly Patients with Acute Myeloid Leukemia: A Phase II Single-Arm Multicenter Study

Acute myeloid leukemia (AML) is a disease affecting older adults, although optimal strategies for treating such patients remain unclear. This prospective phase II, open-label, multicenter study was designed to assess the efficacy and safety of two hematologic growth factors, recombinant human thrombopoietin (rhTPO) and granulocyte colony-stimulating factor (G-CSF), in combination with decitabine, cytarabine, and aclarubicin (D-CTAG regimen) to treat older adults with newly diagnosed AML (Identifier: NCT04168138). The above agents were administered as follows: decitabine (15 mg/m² daily, days 1–5); low-dose cytarabine (10 mg/m² q12 h, days 3–9); rhTPO (15,000 U daily, days 2, 4, 6, 8, 10–24 or until >50×10⁹/L platelets); aclarubicin (14 mg/m² daily, days 3–6); and G-CSF (300 μg daily, days 2–9). We concurrently monitored historic controls treated with decitabine followed by cytarabine, aclarubicin, and G-CSF (D-CAG) only. After the first D-CTAG cycle, the overall response rate (ORR) was 84.2% (16/19), including 13 (73.7%) complete remissions (CRs) and three (15.8%) partial remissions. This CR rate surpassed that of the D-CAG treatment (p < 0.05). Median overall survival (OS) time in the D-CTAG group was 20.2 months (range, 4–31 months), compared with 14 months in the D-CAG group, and 1-year OS was 78%. The proportion of those experiencing grade III–IV thrombocytopenia was significantly lower for D-CTAG (57.9%) than for D-CAG (88.4%; p < 0.05). Ultimately, the curative effect of adding rhTPO was not inferior to that of D-CAG, and D-CTAG proved safer for elderly patients, especially in terms of hematologic toxicity. A prospective phase III randomized study is warranted to confirm these observations.

A prognostic staging system for light-chain amyloidosis using hepatic and renal indicator data from 1,064 Chinese patients

Background

Light-chain (AL) amyloidosis frequently involves severe multiple end-organ damage, thus affecting prognosis. As the current disease staging system is based only on cardiac indicators, we propose a new staging system based on multiple organ indicators to supplement the existing system.

Methods

Patients with AL amyloidosis (n=1,064) from 18 Chinese hospitals were enrolled and divided into test and validation cohorts (4:1). Multivariate analyses were performed to identify the clinical and laboratory factors for inclusion in the new staging system.

Results

A score of 1 was assigned for each of the following-the difference between the involved and uninvolved free light chains ≥100 mg/L, estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m², total bilirubin (Tbil) ≥18 µmol/L, cardiac troponin I ≥0.06 µg/L, and N-terminal pro-brain natriuretic peptide (NT-proBNP) ≥3,600 pg/mL-to divide the patients into five disease stages (0 to IV). There were 220 (20.7%), 291 (27.3%), 251 (23.6%), 178 (16.7%), and 124 (11.7%) patients with stage 0, I, II, III, and IV disease, respectively. Patients with stage II, III, and IV disease had a median overall survival (OS) of 56.9 months [95% confidence interval (CI), 33.9-not reached (NR)], 18.6 months (95% CI, 33.9-NR), and 6.5 months (95% CI, 8.0-24.6) (P<0.001), respectively. The 3-year survival estimates for patients with stages 0, I, II, III, and IV were 90.7%, 71.4%, 59.4%, 39.0%, and 22.1%, respectively.

Conclusions

The new staging system has been developed that incorporates plasma cell-related characteristics in addition to cardiac, renal, and hepatic function parameters. It enhances the risk stratification of patients with AL amyloidosis and is useful when multiple organs are involved.

Downregulation of Chemokine CCL20 Involved in Myeloma Cells Resistant to Elotuzumab and Lenalidomide

Objective

Few studies have focused on investigating resistance mechanisms in myeloma immunotherapy. This study aimed to explore the relevant factor involved in the resistance of Elotuzumab and lenalidomide.

Methods

Cell models which are resistant to Elotuzumab and lenalidomide were constructed; different expression genes in U266/WT (UW) and resistant UR, UE, and URE cells were detected by using gene expression microarray. RT-qPCR validated CCL20 mRNA expression of four cell lines and patient samples; bioinformatics analysis of CCL20 expressions in NDMM and RRMM; ELISA detected the presence of CCL20 in the plasma of MM patients; constructed UR mouse xenograft model to explore whether or not CCL20 reverse lenalidomide treatment in vivo.

Results

Cell models which are resistant to Elotuzumab and lenalidomide (UR, UE, URE) were successfully constructed. CCL20 gene expression decreased in resistant myeloma cell lines and RRMM patients. Furthermore, RRMM patients were found to have lower levels of CCL20 protein in their plasma compared to NDMM. CCL20 increase the sensitivity of drug-resistant myeloma cells to immunomodulatory drugs both in vivo and in vitro.

Conclusion

The expression of CCL20 was decreased in lenalidomide and Elotuzumab resistant U266 cells and in RRMM patients. CCL20 could therefore possibly increase the sensitivity of lenalidomide and Elotuzumab.

Employment of Artificial Intelligence Based on Routine Laboratory Results for the Early Diagnosis of Multiple Myeloma

Objective

In order to enhance the detection rate of multiple myeloma and execute an early and more precise disease management, an artificial intelligence assistant diagnosis system is developed.

Methods

4,187 routine blood and biochemical examination records were collected from Shengjing Hospital affiliated to China Medical University from January 2010 to January 2020, which include 1,741 records of multiple myeloma (MM) and 2,446 records of non-myeloma (infectious diseases, rheumatic immune system diseases, hepatic diseases and renal diseases). The data set was split into training and test subsets with the ratio of 4:1 while connecting hemoglobin, serum creatinine, serum calcium, immunoglobulin (A, G and M), albumin, total protein, and the ratio of albumin to globulin data. An early assistant diagnostic model of MM was established by Gradient Boosting Decision Tree (GBDT), Support Vector Machine (SVM), Deep Neural Networks (DNN), and Random Forest (RF). Out team calculated the precision and recall of the system. The performance of the diagnostic model was evaluated by using the receiver operating characteristic (ROC) curve.

Results

By designing the features properly, the typical machine learning algorithms SVM, DNN, RF and GBDT all performed well. GBDT had the highest precision (92.9%), recall (90.0%) and F1 score (0.915) for the myeloma group. The maximized area under the ROC (AUROC) was calculated, and the results of GBDT (AUC: 0.975; 95% confidence interval (CI): 0.963–0.986) outperformed that of SVM, DNN and RF.

Conclusion

The model established by artificial intelligence derived from routine laboratory results can accurately diagnose MM, which can boost the rate of early diagnosis.

FTY720 induces ferroptosis and autophagy via PP2A/AMPK pathway in multiple myeloma cells

AIMS

Multiple myeloma (MM) is the second hematological plasma cell malignany and sensitive to fingolimod (FTY720), a novel immunosuppressant. Previous study shows FTY720-induced apoptosis and autophagy can cause cell death in MM cells, however, the high death rate cannot fully be explained. The study aims to investigate further mechanism of how FTY720 kills MM cells.

MATERIALS AND METHODS

Experiments are performed on 25 human primary cell samples and two MM cell lines by flow cytometry, fluorescence microscopy, and transmission electron microscopy. Expressions of relative factors are tested by qRT-PCR or western blot.

KEY FINDINGS

Ferroptosis-specific inhibitors, deferoxamine mesylate (DFOM) and ferropstatin-1 (Fer-1), reverse FTY720-induced cell death in MM cells. Glutathione peroxidase 4 (GPX4) and soluble carrier family 7 member 11 (SLC7A11), key regulators of ferroptosis, are highly expressed in primary MM cells and can be decreased by FTY720 at the mRNA and protein level in MM cells. In addition, FTY720 induces other characteristic changes of ferroptosis. Furthermore, FTY720 can dephosphorylate AMP-activated protein kinase subunit ɑ (AMPKɑ) at the Thr172 site by activating protein phosphatase 2A (PP2A) and reduce the expression of phosphorylated eukaryotic elongation factor 2 (eEF2), finally cause MM cell death. Using LB-100, a PP2A inhibitor, AICAR, an agonist of AMPK, and bafilomycin A1 (Baf-A1), an autophagy inhibitor, we discover that FTY720 induces ferroptosis and autophagy through the PP2A/AMPK pathway, and ferroptosis and autophagy can reinforce each other.

SIGNIFICANCE

These results provide a new perspective on the treatment of MM.

miR‑144‑3p inhibits the proliferation, migration and angiogenesis of multiple myeloma cells by targeting myocyte enhancer factor 2A

Multiple myelomas (MM) are the second most common haematological malignancy, for which no curative treatments have been reported to date. MicroRNAs (miRNAs or miRs) have recently been shown to be involved in the proliferation of MM cells. However, the molecular mechanisms through which miRNAs regulate migration and angiogenesis in MM are poorly understood. Accordingly, the present study evaluated the role of miR-144-3p in MM. miR-144-3p exhibited a lower expression in patients with MM and in MM cell lines compared with normal cells (mononuclear cells derived from bone marrow). The transfection of miR-144-3p into MM cells inhibited proliferation, migration and angiogenesis, and induced cell cycle arrest and apoptosis compared to the control cells. Furthermore, miR-144-3p suppressed the transcription and translation of the myocyte enhancer factor 2A (MEF2A) gene and disrupted the expression of vascular endothelial growth factor. The knockdown of MEF2A significantly inhibited the proliferation, migration and angiogenesis of MM cells. However, the overexpression of MEF2A reversed these effects. On the whole, the findings of the present study demonstrate that miR-144-3p exerts antitumour effects by downregulating MEF2A to inhibit the proliferation, migration and angiogenesis of MM cells. This suggests that the miR-144-3p/MEF2A interaction may prove to be a potential therapeutic target for MM.

PIWI-Interacting RNA-004800 Is Regulated by S1P Receptor Signaling Pathway to Keep Myeloma Cell Survival

PIWI-interacting RNA (piRNA) is a kind of non-coding single stranded RNA which plays major roles in epigenetic expressions, genome rearrangement, and regulation of gene and protein. Because piRNAs are abnormally expressed in various cancers, they can be used as novel biomarkers and therapeutic targets. However, the roles of piRNAs in cancer cell growth and survival are not well-known. Here, we are the first to provide evidence that PIWI-interacting RNA-004800 (piR-004800) is overexpressed in both exosomes from multiple myeloma (MM) patients' bone marrow supernatant and primary MM cells. The expression level of piR-004800 is positively correlated with the stages of MM, according to the international staging system (ISS). In MM cell lines, downregulation of piR-004800 induced apoptosis and autophagic cell death. This was accompanied by in vitro and in vivo inhibition of cell proliferation. Our previous study shows that sphingosine-1-phosphate receptor (S1PR) signaling pathway plays a crucial part in MM cell proliferation. In this study, we find that S1PR signaling pathway can regulate the PI3K/Akt/mTOR pathway through control of piR-004800 expressions. Taken together our data supports an oncogenic role for piR-004800 in MM, which sheds insight into a new mechanism that may lead to therapeutic targets in MM, an incurable plasma cell neoplasm.

RASSF1A: A promising target for the diagnosis and treatment of cancer

The Ras association domain family 1 isoform A (RASSF1A), a tumor suppressor, regulates several tumor-related signaling pathways and interferes with diverse cellular processes. RASSF1A is frequently demonstrated to be inactivated by hypermethylation in numerous types of solid cancers. It is also associated with lymph node metastasis, vascular invasion, and chemo-resistance. Therefore, reactivation of RASSF1A may be a viable strategy to block tumor progress and reverse drug resistance. In this review, we have summarized the clinical value of RASSF1A for screening, staging, and therapeutic management of human malignancies. We also highlighted the potential mechanism of RASSF1A in chemo-resistance, which may help identify novel drugs in the future.

Frequency-Specific Changes in the Fractional Amplitude of the Low-Frequency Fluctuations in the Default Mode Network in Medication-Free Patients With Bipolar II Depression: A Longitudinal Functional MRI Study

Objective: This study aimed to examine the treatment-related changes of the fractional amplitude of low-frequency fluctuations (fALFF) in the default mode network (DMN) across different bands after the medication-free patients with bipolar II depression received a 16-week treatment of escitalopram and lithium. Methods: A total of 23 medication-free patients with bipolar II depression and 29 healthy controls (HCs) were recruited. We evaluated the fALFF values of slow 4 (0.027-0.073 Hz) band and slow 5 (0.01-0.027 Hz) band of the patients and compared the results with those of the 29 HCs at baseline. After 16-week treatment of escitalopram with lithium, the slow 4 and slow 5 fALFF values of the patients were assessed and compared with the baselines of patients and HCs. The depressive symptoms of bipolar II depression in patients were assessed with a 17-item Hamilton Depression Rating Scale (HDRS) before and after treatment. Results: Treatment-related effects showed increased slow 5 fALFF in cluster D (bilateral medial superior frontal gyrus, bilateral superior frontal gyrus, right middle frontal gyrus, and bilateral anterior cingulate), cluster E (bilateral precuneus/posterior cingulate, left cuneus), and cluster F (left angular, left middle temporal gyrus, left superior temporal gyrus, and left supramarginal gyrus) in comparison with the baseline of the patients. Moreover, a positive association was found between the increase in slow 5 fALFF values (follow-up value minus the baseline values) in cluster D and the decrease in HDRS scores (baseline HDRS scores minus follow-up HDRS scores) at follow-up, and the same association between the increase in slow 5 fALFF values and the decrease in HDRS scores was found in cluster E. Conclusions: The study reveals that the hypoactivity of slow 5 fALFF in the DMN is related to depression symptoms and might be corrected by the administration of escitalopram with lithium, implying that slow 5 fALFF of the DMN plays a key role in bipolar depression.

Is complement C1q a potential marker for tumor burden and immunodeficiency in multiple myeloma?

Multiple myeloma (MM) patients are immunodeficient. Complement C1q is an important cofactor of both nonspecific and humoral immunity, and it participates in the immunomodulation of multiple tumors. Thus, this study aimed to determine the risk factors and clinical significance of C1q expression in MM patients. In total, 193 MM patients were examined. The mean value of C1q in the patient group (130.46 ± 36.17 mg/L), was lower than that in the control group (anemia and nonmalignant hematologic disease). C1q dynamically changed with different MM stages and was recovered to normal levels when the disease was in remission; however, it decreased again after disease progression. The risk factors of C1q reduction included Durie-Salmon stage and the immunoglobulin type of the disease. In conclusion, C1q appears to be a useful biomarker of tumor burden and a prognostic factor of disease relapse. C1q is a potential marker of the immunodeficiency status in MM patients.

Bioinformatic analysis suggests that UGT2B15 activates the Hippo‑YAP signaling pathway leading to the pathogenesis of gastric cancer

Gastric cancer (GC) is one of the most common malignancies that threatens human health. As the molecular mechanisms unerlying GC are not completely understood, identification of genes related to GC could provide new insights into gene function as well as potential treatment targets. We discovered that UGT2B15 may contribute to the pathogenesis and progression of GC using GEO data and bioinformatic analysis. Using TCGA data, UGT2B15 mRNA was found to be significantly overexpressed in GC tissues; patients with higher UGT2B15 had a poorer prognosis. It was further discovered that UGT2B15 and FOXA1 were both upregulated, and UGT2B15 and Foxa1 were positively correlated in GC. It is known that Foxa1 is a vital threshold to activate the Hippo-YAP signaling pathway. In addition, we suggest that a potential molecular mechanisms includes UGT2B15 which may upregulate Foxa1, activate the Hippo-YAP signaling pathway and contribute to the development of GC. Taken together, our findings demonstrate that UGT2B15 may be an oncogene in GC and is a promising therapeutic target for cancer treatment.

A nonmyeloablative chimeric mouse model accurately defines microglia and macrophage contribution in glioma

Aims

Resident and peripherally derived glioma associated microglia/macrophages (GAMM) play a key role in driving tumour progression, angiogenesis, invasion and attenuating host immune responses. Differentiating these cells’ origins is challenging and current preclinical models such as irradiation‐based adoptive transfer, parabiosis and transgenic mice have limitations. We aimed to develop a novel nonmyeloablative transplantation (NMT) mouse model that permits high levels of peripheral chimerism without blood‐brain barrier (BBB) damage or brain infiltration prior to tumour implantation.

Methods

NMT dosing was determined in C57BL/6J or Pep3/CD45.1 mice conditioned with concentrations of busulfan ranging from 25 mg/kg to 125 mg/kg. Donor haematopoietic cells labelled with eGFP or CD45.2 were injected via tail vein. Donor chimerism was measured in peripheral blood, bone marrow and spleen using flow cytometry. BBB integrity was assessed with anti‐IgG and anti‐fibrinogen antibodies. Immunocompetent chimerised animals were orthotopically implanted with murine glioma GL‐261 cells. Central and peripheral cell contributions were assessed using immunohistochemistry and flow cytometry. GAMM subpopulation analysis of peripheral cells was performed using Ly6C/MHCII/MerTK/CD64.

Results

NMT achieves >80% haematopoietic chimerism by 12 weeks without BBB damage and normal life span. Bone marrow derived cells (BMDC) and peripheral macrophages accounted for approximately 45% of the GAMM population in GL‐261 implanted tumours. Existing markers such as CD45 high/low proved inaccurate to determine central and peripheral populations while Ly6C/MHCII/MerTK/CD64 reliably differentiated GAMM subpopulations in chimerised and unchimerised mice.

Conclusion

NMT is a powerful method for dissecting tumour microglia and macrophage subpopulations and can guide further investigation of BMDC subsets in glioma and neuro‐inflammatory diseases.

Linc00483 as ceRNA regulates proliferation and apoptosis through activating MAPKs in gastric cancer

Long non‐coding RNAs (lncRNAs) are important regulators of many cellular processes, and their aberrant expression and/or function is associated with many different diseases, including cancer. However, the identification of functional lncRNAs in gastric cancer is still a challenge. In this study, we describe a novel functional lncRNA, linc00483, that is upregulated and associated with tumorigenesis, tumour size, metastasis and poor prognosis in gastric cancer. In our study, linc00483 promoted gastric cancer cell proliferation, invasiveness and metastasis in vitro and in vivo. Mechanistically, upregulated expression of linc00483 in gastric cancer acts as a sponge to absorb endogenous tumour suppressor miR‐30a‐3p. Furthermore, it restores SPAG9 expression, which is negatively regulated by miR‐30a‐3p, and actives MAPK signaling pathway in gastric cancer cells. Thus, linc00483 is an oncogenic lncRNA in gastric cancer and targeting linc00483 or its pathway can potentially be useful in development of targeted therapies for patients with gastric cancer. Our results show that linc00483 is an important regulator in carcinogenesis and may be a useful biomarker to predict prognosis of gastric cancer patients. We believe our findings are novel and will be of interest to scientists working in many areas related to biomarkers in cancer.

Hypomethylation agent decitabine restores drug sensitivity by depressing P-glycoprotein activity through MAPK signaling pathway

The multidrug resistance (MDR) continues to be an obstacle in the treatment of both hematological and solid tumors. Hypomethylation agent, decitabine (5-Aza-dC), is an experimental agent in MDR therapy, while the mechanism is not very clear. In the present study, we demonstrated 5-Aza-dC may reverse MDR induced by P-glycoprotein (P-gp) coded by mdr1 gene in both hematologic K562/ADR cells and solid tumor MCF-7/ADR cells with time and dose-dependent manner. 5-Aza-dC significantly increased drug sensitivity in patients' leukemic cells which had higher expression of mdr1 gene. Both total protein and membrane P-gp expression were up-regulated with 5-Aza-dC treatment in K562/ADR and MCF-7/ADR cells. However, accumulation of adriamycin and rhodamine 123 were increased which suggested the depression of P-gp activity. Gene expression profiling was performed and activation of MAPK signaling pathway was identified as the most significant change affected by 5-Aza-dC. Inhibition of MAPK pathway could increase P-gp activity. Our data suggested that hypomethylation agent decitabine restores drug sensitivity in the P-gp-induced MDR phenotype by depressing of P-gp activity as drug pump partly through MAPK signaling pathway.

Live kinase B1 maintains CD34+CD38- AML cell proliferation and self-renewal

Live kinase B1 (LKB1) has been recognized as a tumor suppressor in many human cancers; however, LKB1 maintains self-renewal of hematopoietic stem cells (HSCs). The existence of leukemia stem cells (LSCs) is responsible for drug resistance and leukemia relapse. In acute myeloid leukemia (AML), CD34⁺CD38^- fraction is the most enriched compartment for LSCs. We found that LKB1 was upregulated in CD34⁺CD38^- AML cells. LKB1 downregulation suppressed the long-term proliferation of CD34⁺CD38^- AML cells, induced CD34⁺CD38^- AML cells into G2/M phase, and enhanced the sensitivity of CD34⁺CD38^- AML cells to chemotherapy. Furthermore, LKB1 downregulation in CD34⁺CD38^- AML cells inhibited tumor formation in NOD-SCID mice. Downregulation of LKB1 gene makes LSCs partly loose the characters as stem cells. Gene expression microarray showed that MAPK/ERK pathway was implicated in the regulation of CD34⁺CD38^- AML cell proliferation by LKB1. Together, these findings demonstrate that LKB1 plays an important role in the maintenance of LSCs, which may be responsible for drug resistance and AML relapse.

Downregulation of LIMK1-ADF/cofilin by DADS inhibits the migration and invasion of colon cancer

This study aimed to explore whether the downregulation of LIM kinase 1 (LIMK1)-actin depolymerization factor (ADF, also known as destrin)/cofilin by diallyl disulfide (DADS) inhibited the migration and invasion of colon cancer. Previous studies have shown that silencing LIMK1 could significantly enhance the inhibitory effect of DADS on colon cancer cell migration and invasion, suggesting that LIMK1 was a target molecule of DADS, which needed further confirmation. This study reported that LIMK1 and destrin were highly expressed in colon cancer and associated with poor prognosis of patients with colon cancer. Also, the expression of LIMK1 was positively correlated with the expression of destrin. The overexpression of LIMK1 significantly promoted colon cancer cell migration and invasion. DADS obviously inhibited migration and invasion by suppressing the phosphorylation of ADF/cofilin via downregulation of LIMK1 in colon cancer cells. Furthermore, DADS-induced suppression of cell proliferation was enhanced and antagonized by the knockdown and overexpression of LIMK1 in vitro and in vivo, respectively. Similar results were observed for DADS-induced changes in the expression of vimentin, CD34, Ki-67, and E-cadherin in xenografted tumors. These results indicated that LIMK1 was a potential target molecule for the inhibitory effect of DADS on colon cancer cell migration and invasion.

RASSF1A inhibits gastric cancer cell proliferation by miR-711- mediated downregulation of CDK4 expression

Although interaction with DNA repair proteins has demonstrated that RASSF1A is a tumour suppressor gene, much attention has been directed in recent years towards its roles in regulating the cell cycle. However, the precise mechanism remains unclear. Uncovering how RASSF1A participates in regulating the cell cycle is critical to exploring effective therapeutic targets for gastric cancer. Here we show that RASSF1A could regulate 14 miRNAs’ expression in the typical human gastric cancer line SGC-7901, of which miR-711 was upregulated the most. Moreover, for SGC-7901 cells, miR-711 was found to downregulate CDK4 expression, and to arrest the cell cycle in the G1 phase. Our results suggest that RASSF1A inhibits the proliferation of gastric cancer cells by upregulating the expression of miR-711, which arrested gastric cancer cells in the G1 phase by downregulating expression of CDK4. This finding might provide us with a novel therapeutic target for gastric cancer by increasing RASSF1A expression via miR-711 regulation.

The effect of S1P receptor signaling pathway on the survival and drug resistance in multiple myeloma cells

Multiple myeloma (MM) remains incurable by conventional chemotherapy. Sphingosine-1-phosphate (S1P) receptor-mediated signaling has been recently demonstrated to have critical roles in cell survival and drug resistance in a number of hematological malignancies. To dissect the roles of S1P receptor pathway in MM, we systematically examined cell viability and protein expression associated with cell survival and drug resistance in MM cell lines upon treatment with either pathway activator (S1P) or inhibitor (FTY720). Our results reveal that FTY720 inhibits cell proliferation by downregulating expression of target genes, while S1P has an opposite effect. Knocking down of S1P receptor S1P5R results in a reduction of cell survival-related gene expression; however, it does not have impacts on expression of drug resistance genes. These results suggest that S1P signaling plays a role in cell proliferation and drug resistance in MM, and targeting this pathway will provide a new therapeutic direction for MM management.

Acute mono-megakaryoblastic leukemia associated with extreme thrombocytosis and complex karyotype abnormalities

Patient: Female, 55

Final Diagnosis: Acute leukemia

Symptoms: Thrombocytosis

Medication: Idarubicin HCl (Zavedos), Pfizer

Clinical Procedure: —

Specialty: Hematology

The proteasome inhibitor bortezomib reverses P-glycoprotein-mediated leukemia multi-drug resistance through the NF-kappaB pathway

Multi-drug resistance (MDR) is one of the obstacles for leukemia therapy, the major cause is an overexpression of P-glycoprotein (P-gp) leading to increased drug efflux. We investigated the reversion of multi-drug resistance and the possible mechanism by which the proteasome inhibitor bortezomib affects the expression of the multi-drug resistance gene mdrl in the K562/DNR cell line. The drug resistance of the cells and the cellular toxicity of bortezomib were confirmed by MTT. Intracellular drug concentrations and cell apoptosis were detected by flow cytometry. The expression of mdrl mRNA was examined by fluorescence quantitative PCR. The expression levels of nuclear factor-kappa B (NF-kappaB), inhibitor of NF-kappaB (IkappaB) and P-gp were detected by western blotting, and NF-kappaB activity was detected by ELISA. DNR-induced apoptosis increased in a dose-dependent manner after adding bortezomib. Bortezomib decreased IkappaB degradation, decreased NF-kappaB and NF-kappaB p65 activity, reduced P-gp/mdr1 mRNA expression, and increased the intracellular DNR concentration in K562/DNR cells in vitro. The bortezomib reversed leukemic multi-drug resistance in a dose-dependent manner as the result of decreasing IkappaB degradation, thus preventing the translocation of NF-kappaB into the nucleus and leading the down-regulation of mdr1 and a reduction in P-gp expression. Therefore, the intracellular drug concentration increased, and then apoptosis was induced.

Dynamical and structural analysis of a T cell survival network identifies novel candidate therapeutic targets for large granular lymphocyte leukemia

The blood cancer T cell large granular lymphocyte (T-LGL) leukemia is a chronic disease characterized by a clonal proliferation of cytotoxic T cells. As no curative therapy is yet known for this disease, identification of potential therapeutic targets is of immense importance. In this paper, we perform a comprehensive dynamical and structural analysis of a network model of this disease. By employing a network reduction technique, we identify the stationary states (fixed points) of the system, representing normal and diseased (T-LGL) behavior, and analyze their precursor states (basins of attraction) using an asynchronous Boolean dynamic framework. This analysis identifies the T-LGL states of 54 components of the network, out of which 36 (67%) are corroborated by previous experimental evidence and the rest are novel predictions. We further test and validate one of these newly identified states experimentally. Specifically, we verify the prediction that the node SMAD is over-active in leukemic T-LGL by demonstrating the predominant phosphorylation of the SMAD family members Smad2 and Smad3. Our systematic perturbation analysis using dynamical and structural methods leads to the identification of 19 potential therapeutic targets, 68% of which are corroborated by experimental evidence. The novel therapeutic targets provide valuable guidance for wet-bench experiments. In addition, we successfully identify two new candidates for engineering long-lived T cells necessary for the delivery of virus and cancer vaccines. Overall, this study provides a bird's-eye-view of the avenues available for identification of therapeutic targets for similar diseases through perturbation of the underlying signal transduction network.

T-LGL leukemia is a blood cancer characterized by an abnormal increase in the abundance of a type of white blood cell called T cell. Since there is no known curative therapy for this disease, identification of potential therapeutic targets is of utmost importance. Experimental identification of manipulations capable of reversing the disease condition is usually a long, arduous process. Mathematical modeling can aid this process by identifying potential therapeutic interventions. In this work, we carry out a systematic analysis of a network model of T cell survival in T-LGL leukemia to get a deeper insight into the unknown facets of the disease. We identify the T-LGL status of 54 components of the system, out of which 36 (67%) are corroborated by previous experimental evidence and the rest are novel predictions, one of which we validate by follow-up experiments. By deciphering the structure and dynamics of the underlying network, we identify component perturbations that lead to programmed cell death, thereby suggesting several novel candidate therapeutic targets for future experiments.