N6-methyladenosine facilitates mitochondrial fusion of colorectal cancer cells via induction of GSH synthesis and stabilization of OPA1 mRNA.

Mitochondria undergo fission and fusion that are critical for cell survival and cancer development, while the regulatory factors for mitochondrial dynamics remain elusive. Herein we found that RNA m6A accelerated mitochondria fusion of colorectal cancer (CRC) cells. Metabolomics analysis and function studies indicated that m6A triggered the generation of glutathione (GSH) via the upregulation of RRM2B-a p53-inducible ribonucleotide reductase subunit with anti-reactive oxygen species potential. This in turn resulted in the mitochondria fusion of CRC cells. Mechanistically, m6A methylation of A1240 at 3'UTR of RRM2B increased its mRNA stability via binding with IGF2BP2. Similarly, m6A methylation of A2212 at the coding sequence (CDS) of OPA1-an essential GTPase protein for mitochondrial inner membrane fusion-also increased mRNA stability and triggered mitochondria fusion. Targeting m6A through the methyltransferase inhibitor STM2457 or the dm6ACRISPR system significantly suppressed mitochondria fusion. In vivo and clinical data confirmed the positive roles of the m6A/mitochondrial dynamics in tumor growth and CRC progression. Collectively, m6A promoted mitochondria fusion via induction of GSH synthesis and OPA1 expression, which facilitated cancer cell growth and CRC development.

Infusion-Related Reactions Induced by Cadonilimab (PD-1/CTLA-4 Bispecific Antibody): Seven Case Reports.

Introduction: Cadonilimab (AK104) is an innovative human programmed cell death-1 (PD-1)/cytotoxic T lymphocyte antigen-4 (CTLA-4) bispecific antibody. Compared with the combination therapy of PD-1 and CTLA-4 blockers, less cellular toxicity of cadonilimab was significantly manifested. As one of the characteristic adverse effects of cadonilimab, infusion-related reactions (IRRs) represent fever, chills, rash, decreased blood pressure, and other symptoms. Case Presentation: Here, we documented seven cases of IRRs after the administration of cadonilimab. The symptoms of IRRs were relieved after the discontinuation of cadonilimab and the administration of diphenhydramine, dexamethasone, and cimetidine. Notably, 3 patients were able to tolerate the subsequent cadonilimab therapy under the pretreatment. Conclusion: In this study, we discovered that cadonilimab-related IRRs might be lessened or prevented by administering medication and the proper pretreatment and lowering the infusion rate.

METTL3 promotes cellular senescence of colorectal cancer via modulation of CDKN2B transcription and mRNA stability.

Cellular senescence plays a critical role in cancer development, but the underlying mechanisms remain poorly understood. Our recent study uncovered that replicative senescent colorectal cancer (CRC) cells exhibit increased levels of mRNA N6-methyladenosine (m6A) and methyltransferase METTL3. Knockdown of METTL3 can restore the senescence-associated secretory phenotype (SASP) of CRC cells. Our findings, which were confirmed by m6A-sequencing and functional studies, demonstrate that the cyclin-dependent kinase inhibitor 2B (CDKN2B, encoding p15INK4B) is a mediator of METTL3-regulated CRC senescence. Specifically, m6A modification at position A413 in the coding sequence (CDS) of CDKN2B positively regulates its mRNA stability by recruiting IGF2BP3 and preventing binding with the CCR4-NOT complex. Moreover, increased METTL3 methylates and stabilizes the mRNA of E2F1, which binds to the -208 to -198 regions of the CDKN2B promoter to facilitate transcription. Inhibition of METTL3 or specifically targeting CDKN2B methylation can suppress CRC senescence. Finally, the METTL3/CDKN2B axis-induced senescence can facilitate M2 macrophage polarization and is correlated with aging and CRC progression. The involvement of METTL3/CDKN2B in cell senescence provides a new potential therapeutic target for CRC treatment and expands our understanding of mRNA methylation's role in cellular senescence.

Erratum: N6-methyladenosine-induced ERRγ triggers chemoresistance of cancer cells through upregulation of ABCB1 and metabolic reprogramming: Erratum.

[This corrects the article DOI: 10.7150/thno.40144.].

N6-Methyladenosine Promotes Translation of VEGFA to Accelerate Angiogenesis in Lung Cancer.

Angiogenesis is hijacked by cancer to support tumor growth. RNA modifications such as N6-methyladenosine (m6A) can regulate several aspects of cancer, including angiogenesis. Here, we find that m6A triggers angiogenesis in lung cancer by upregulating VEGFA, a central regulator of neovasculature and blood vessel growth. m6A-sequencing and functional studies confirmed that m6A modification of the 5'UTR (untranslated region) of VEGFA positively regulates its translation. Specifically, methylation of a 5'UTR internal ribosome entry site (IRES) recruited the YTHDC2/eIF4GI complex to trigger cap-independent translation initiation. Intriguingly, the m6A methylation site A856 of the 5'UTR was located within the conserved upstream open reading frame (uORF) of VEGFA IRES-A, which overcomes uORF-mediated translation suppression while facilitating G-quadruplex-induced translation of VEGFA. Targeted specific demethylation of VEGFA m6A significantly decreased expression of VEGFA and reduced lung cancer cell-driven angiogenesis. In vivo and clinical data confirmed the positive effects of m6A modification of VEGFA on angiogenesis and tumor growth of lung cancer. This study not only reveals that the m6A/VEGFA axis is a potential target for lung cancer therapy but also expands our understanding of the impact of m6A modification of IRES in the 5'UTR of mRNA on translation regulation. SIGNIFICANCE: Methylation of the 5'UTR IRES of VEGFA mRNA increases cap-independent translation via recruitment of the YTHDC2/eIF4GI complex, which stimulates angiogenesis to promote lung tumor growth.

Working mode of oncology surgical pharmacy in China.

Surgery plays an irreplaceable role in the prevention, diagnosis, staging, reconstruction, and rehabilitation in the overall management of cancer. Nevertheless, it is difficult for surgeons and nurses to take into account the details of medication management, considering the impact of  surgery on the patient's physical function and the complexity of anti-tumor  treatment with comorbidity. The pharmaceutical care services previously  provided by pharmacists in oncology focus more on the internal medicine  system, not widely the surgical field. At present, the pharmaceutical working  mode in oncology surgery has not well been formed around China, and the  whole process medication management needs to be improved. In 2015, the  GuangDong Pharmaceutical Association came up with the concept of  surgical pharmacist in China and subsequently created its position. In 2021, the GuangDong Pharmaceutical Association established a new discipline  termed "surgical pharmacy", which is the knowledge system of surgical pharmacists, and also tried to differentiate surgical pharmacy into  diverse areas, such as oncology surgical pharmacy. This article introduced a  working mode of surgical pharmacists in China that providing pharmaceutical  care services in perioperative period around anti-tumor, anti- infection, anesthesia, anticoagulation, blood pressure, blood glucose, nutrition, and pain management, to improve quality of life for patients.

La cirugía desempeña un papel insustituible en la prevención, diagnóstico, estadificación, reconstrucción y rehabilitación en el tratamiento  global del cáncer. Sin embargo, es difícil que cirujanos y personal de  enfermería tengan en cuenta todos los aspectos de la gestión de la medicación,  como el impacto de la cirugía en la función física del paciente y la  complejidad del tratamiento antitumoral con sus comorbilidades. Los servicios  de atención farmacéutica que anteriormente prestaban los farmacéuticos en  oncología se centraban más en aspectos de la medicina interna, y no  ampliamente en el ámbito quirúrgico. En la actualidad, el modo de trabajo  farmacéutico en la cirugía oncológica aún no está definido en China, y existe  una necesidad de mejorar la gestión de la medicación de todo el proceso  asistencial. En 2015, la Asociación Farmacéutica de GuangDong propuso la  creación del rol de farmacéutico quirúrgico en China y posteriormente creó su  puesto de trabajo. En 2021, la Asociación Farmacéutica de GuangDong  Estableció una nueva disciplina denominada "farmacia quirúrgica", que es el  área de conocimiento de los farmacéuticos quirúrgicos, y también intentó  diferenciar la farmacia quirúrgica en distintas subáreas, como la farmacia  quirúrgica oncológica. Este artículo presenta el modo de trabajo de los  farmacéuticos quirúrgicos en China, que proporciona servicios de atención  farmacéutica en el periodo perioperatorio de los pacientes incorporando los  distintos aspectos del tratamiento antitumoral, control de infecciones,  anestesia, anticoagulación, control de la presión arterial y la glucosa en  sangre, nutrición y tratamiento del dolor, con el objetivo de mejorar la calidad  de vida de los pacientes.

N6-methyladenosine-mediated LDHA induction potentiates chemoresistance of colorectal cancer cells through metabolic reprogramming.

Background: Chemoresistance to 5-fluorouracil (5-FU) is a major barrier to influence the treatment efficiency of colorectal cancer (CRC) patients, while the precise molecular mechanisms underlying 5-FU resistance remain to be fully elucidated. Methods: The metabolic profiles including ATP generation, glucose consumption, lactate generation, and oxygen consumption rate (OCR) in 5-FU resistant CRC cells were compared with those in their parental cells. Subsequently, a series of in vitro and in vivo experiments were carried out to investigate the mechanisms responsible for metabolic reprogramming of 5-FU resistant CRC cells. Results: We found that 5-FU resistant CRC cells showed increased levels of ATP generation, glucose consumption, lactate generation, and OCR as compared with those in their parental cells. Further, increased levels of mRNA N6-methyladenosine (m6A) and methyltransferase-like 3 (METTL3) were observed in 5-FU resistant CRC cells. Inhibition or knockdown of METTL3 can suppress glycolysis and restore chemosensitivity of 5-FU resistant CRC cells. Mechanistically, METTL3 enhances the expression of LDHA, which catalyzes the conversion of pyruvate to lactate, to trigger glycolysis and 5-FU resistance. METTL3 can increase the transcription of LDHA via stabilizing mRNA of hypoxia-inducible factor (HIF-1α), further, METTL3 also triggers the translation of LDHA mRNA via methylation of its CDS region and recruitment of YTH domain-containing family protein 1 (YTHDF1). Targeted inhibition of METTL3/LDHA axis can significantly increase the in vitro and in vivo 5-FU sensitivity of CRC cells. Conclusion: Our study indicates that METTL3/LDHA axis-induced glucose metabolism is a potential therapy target to overcome 5-FU resistance in CRC cells.

RNA m1A methylation regulates glycolysis of cancer cells through modulating ATP5D.

Studies on biological functions of RNA modifications such as N6-methyladenosine (m6A) in mRNA have sprung up in recent years, while the roles of N1-methyladenosine (m1A) in cancer progression remain largely unknown. We find m1A demethylase ALKBH3 can regulate the glycolysis of cancer cells via a demethylation activity dependent manner. Specifically, sequencing and functional studies confirm that ATP5D, one of the most important subunit of adenosine 5'-triphosphate synthase, is involved in m1A demethylase ALKBH3-regulated glycolysis of cancer cells. The m1A modified A71 at the exon 1 of ATP5D negatively regulates its translation elongation via increasing the binding with YTHDF1/eRF1 complex, which facilitates the release of message RNA (mRNA) from ribosome complex. m1A also regulates mRNA stability of E2F1, which directly binds with ATP5D promoter to initiate its transcription. Targeted specific demethylation of ATP5D m1A by dm1ACRISPR system can significantly increase the expression of ATP5D and glycolysis of cancer cells. In vivo data confirm the roles of m1A/ATP5D in tumor growth and cancer progression. Our study reveals a crosstalk of mRNA m1A modification and cell metabolism, which expands the understanding of such interplays that are essential for cancer therapeutic application.

Modelo de trabajo de la farmacia quirúrgicaoncológica en China / Working mode of oncology surgical pharmacy in China

La cirugía desempeña un papel insustituible en la prevención, diagnóstico, estadificación, reconstrucción y rehabilitación en el tratamiento globaldel cáncer. Sin embargo, es difícil que cirujanos y personal de enfermeríatengan en cuenta todos los aspectos de la gestión de la medicación, comoel impacto de la cirugía en la función física del paciente y la complejidaddel tratamiento antitumoral con sus comorbilidades. Los servicios de atenciónfarmacéutica que anteriormente prestaban los farmacéuticos en oncología secentraban más en aspectos de la medicina interna, y no ampliamente en elámbito quirúrgico. En la actualidad, el modo de trabajo farmacéutico en lacirugía oncológica aún no está definido en China, y existe una necesidad demejorar la gestión de la medicación de todo el proceso asistencial. En 2015,la Asociación Farmacéutica de GuangDong propuso la creación del rol defarmacéutico quirúrgico en China y posteriormente creó su puesto de trabajo.En 2021, la Asociación Farmacéutica de GuangDong estableció una nuevadisciplina denominada “farmacia quirúrgica”, que es el área de conocimientode los farmacéuticos quirúrgicos, y también intentó diferenciar la farmaciaquirúrgica en distintas subáreas, como la farmacia quirúrgica oncológica.Este artículo presenta el modo de trabajo de los farmacéuticos quirúrgicosen China, que proporciona servicios de atención farmacéutica en el periodoperioperatorio de los pacientes incorporando los distintos aspectos del tratamiento antitumoral, control de infecciones, anestesia, anticoagulación, controlde la presión arterial y la glucosa en sangre, nutrición y tratamiento del dolor,con el objetivo de mejorar la calidad de vida de los pacientes. (AU)

Surgery plays an irreplaceable role in the prevention, diagnosis, staging, reconstruction, and rehabilitation in the overall management of cancer. Nevertheless, it is difficult for surgeons and nurses to take into accountthe details of medication management, considering the impact of surgeryon the patient’s physical function and the complexity of anti-tumor treatmentwith comorbidity. The pharmaceutical care services previously provided bypharmacists in oncology focus more on the internal medicine system, notwidely the surgical field. At present, the pharmaceutical working mode inoncology surgery has not well been formed around China, and the wholeprocess medication management needs to be improved. In 2015, theGuangDong Pharmaceutical Association came up with the concept of surgical pharmacist in China and subsequently created its position. In 2021,the GuangDong Pharmaceutical Association established a new disciplinetermed “surgical pharmacy”, which is the knowledge system of surgicalpharmacists, and also tried to differentiate surgical pharmacy into diverseareas, such as oncology surgical pharmacy. This article introduced a working mode of surgical pharmacists in China that providing pharmaceutical care services in perioperative period around anti-tumor, anti-infection,anesthesia, anticoagulation, blood pressure, blood glucose, nutrition, andpain management, to improve quality of life for patients. (AU)

Rituximab Concentration Varies in Patients With Different Lymphoma Subtypes and Correlates With Clinical Outcome.

Individual variations in concentrations of rituximab in different B cell non-Hodgkin's lymphoma subtypes and their relevance to efficacy were still unclear. From 2016 to 2021, a prospective clinical trial was conducted, and 510 samples with 6 uncommon subtypes of B-cell lymphoma were enrolled to examine the pharmacokinetic behaviour of rituximab and its impact on clinical outcomes, including complete response (CR), progression-free survival (PFS) and overall survival (OS). Considerable variability was observed in the rituximab trough concentration in the first cycle (C1-trough, 1.16-55.52 µg/ml) in patients with different lymphoma subtypes. Patients with "double-hit" lymphoma (4.01 ± 0.77 µg/ml) or mantle cell lymphoma (MCL; 15.65 ± 16.45 µg/ml) had much lower C1-trough and worse outcomes. Great individual variation in the C1-trough existed among patients with mucosa-associated lymphoma (MALT), and the high C1-trough observed in patients treated with the RB regimen was associated with a better response than was obtained with R-CHOP (38.41 ± 14.13 µg/ml vs 15.49 ± 8.80 µg/ml, p = 0.0029). Despite the high aggressiveness of the cancer, Burkitt lymphoma patients receiving intensive chemotherapy had the highest C1-trough (28.85 ± 9.35 µg/ml) and maintained long-term PFS. The C1-trough in patients with mixed, unclassifiable B-cell lymphoma was close to 20 µg/ml, and these patients had acceptable outcomes. Overall, a low rituximab C1-trough was associated with adverse consequences, including persistent progression, early recurrence and a short OS, however, some high-risk factors appeared to be balanced by the presence of a high C1-trough. Basal levels of circulating CD19+ lymphocytes differed between and within patients with diverse lymphoma subtypes and were negatively correlated with C1-trough. Therefore, the traditional doses of rituximab are inadequate for patients with "double-hit" lymphoma and MCL. Increasing the initial rituximab dose according to the disease, high-risk factors and even the baseline CD19+ lymphocyte count will be new methods to optimize therapeutic regimens for patients with different lymphoma subtypes.

Clinical pharmacist participation in selecting and dosing targeted drugs for a patient with ALK-positive non-small cell lung cancer: a case report.

Ceritinib and alectinib are recommended as the second-line therapies in the 2019 Chinese Society of Clinical Oncology (CSCO) guidelines for patients with anaplastic lymphoma kinase (ALK) positive non-small-cell lung cancer (NSCLC) in whom the first-line therapy has failed, but no optimal second-line treatment has been identified. Before 2018, the approved dose of ceritinib in the United States and many other countries was 750 mg/d fasted. In China, the approved dose was 450 mg/d fed although the dose of 750 mg/d fasted is still used in clinical practices. In our current case, a clinical pharmacist was involved in the selection and dose adjustment of a targeted drug for an ALK-positive NSCLC patient. The selection of second-line targeted drugs is based mainly on the results of clinical trials and real-world data of ceritinib and aletinib, along with the comprehensive analysis of health insurance policy, pharmacoeconomics, and drug accessibility. Alectinib may be more efficacious than ceritinib is in second-line settings. However, in our current case, the patient finally chose ceritinib after considering the drug prices and the health insurance policy. The clinical pharmacist optimized the dosage of ceritinib from 750 mg/d fasted to 450 mg/d fed, which not only improved the patient's medication compliance but also ensured the safety and efficacy of the drug; in addition, it lowered the financial burden of both the health insurance system and the patient, offering a good example for rational drug use and health insurance cost reduction. In conclusion, in choosing second-line targeted therapy for ALK-rearranged NSCLC, a variety of factors should be considered, including clinical efficacy, adverse effects, health insurance policy, drug price, and drug accessibility, and the dosage of ceritinib should be optimized to 450 mg/d fed in real-world settings.

N6 -Methyladenosine Regulates mRNA Stability and Translation Efficiency of KRT7 to Promote Breast Cancer Lung Metastasis.

The roles of RNA modification during organ metastasis of cancer cells are not known. Here we established breast cancer lung metastasis cells by three rounds of selection of lung metastatic subpopulations in vivo and designated them as BCLMF3 cells. In these cells, mRNA N6 -methyladenosine (m6A) and methyltransferase METTL3 were increased, while the demethylase FTO was decreased. Epi-transcriptome and transcriptome analyses together with functional studies identified keratin 7 (KRT7) as a key effector for m6A-induced breast cancer lung metastasis. Specifically, increased METTL3 methylated KRT7-AS at A877 to increase the stability of a KRT7-AS/KRT7 mRNA duplex via IGF2BP1/HuR complexes. Furthermore, YTHDF1/eEF-1 was involved in FTO-regulated translational elongation of KRT7 mRNA, with methylated A950 in KRT7 exon 6 as the key site for methylation. In vivo and clinical studies confirmed the essential roles of KRT7, KRT7-AS, and METTL3 for lung metastasis and clinical progression of breast cancer. Collectively, m6A promotes breast cancer lung metastasis by increasing the stability of a KRT7-AS/KRT7 mRNA duplex and translation of KRT7. SIGNIFICANCE: This study suggests that N6 -methyladenosine is a key driver and potential therapeutic target in breast cancer metastasis.

Use of a Remote Oncology Pharmacy Service Platform for Patients With Cancer During the COVID-19 Pandemic: Implementation and User Acceptance Evaluation.

BACKGROUND: The COVID-19 outbreak has increased challenges associated with health management, especially cancer management. In an effort to provide continuous pharmaceutical care to cancer patients, Sun Yat-sen University Cancer Center (SYSUCC) implemented a remote pharmacy service platform based on its already existing web-based hospital app known as Cloud SYSUCC. OBJECTIVE: The aim of this study was to investigate the characteristics, acceptance, and initial impact of the Cloud SYSUCC app during a COVID-19 outbreak in a tertiary cancer hospital in China. METHODS: The total number of online prescriptions and detailed information on the service were obtained during the first 6 months after the remote service platform was successfully set up. The patients' gender, age, residence, primary diagnosis, drug classification, weekly number of prescriptions, and prescribed drugs were analyzed. In addition, a follow-up telephonic survey was conducted to evaluate patients' satisfaction in using the remote prescription service. RESULTS: A total of 1718 prescriptions, including 2022 drugs for 1212 patients, were delivered to 24 provinces and municipalities directly under the Central Government of China between February 12, 2020, and August 11, 2020. The majority of patients were female (841/1212, 69.39%), and 90.18% (1093/1212) of them were aged 31-70 years old. The top 3 primary diagnoses for which remote medical prescriptions were made included breast cancer (599/1212, 49.42%), liver cancer (249/1212, 20.54%), and thyroid cancer (125/1212, 10.31%). Of the 1718 prescriptions delivered, 1435 (83.5%) were sent to Guangdong Province and 283 (16.5%) were sent to other provinces in China. Of the 2022 drugs delivered, 1012 (50.05%) were hormonal drugs. The general trend in the use of the remote prescription service declined since the 10th week. A follow-up telephonic survey found that 88% (88/100) of the patients were very satisfied, and 12% (12/100) of the patients were somewhat satisfied with the remote pharmacy service platform. CONCLUSIONS: The remote pharmacy platform Cloud SYSUCC is efficient and convenient for providing continuous pharmaceutical care to patients with cancer during the COVID-19 crisis. The widespread use of this platform can help to reduce person-to-person transmission as well as infection risk for these patients. Further efforts are needed to improve the quality and acceptance of the Cloud SYSUCC platform, as well as to regulate and standardize the management of this novel service.

Low initial trough concentration of rituximab is associated with unsatisfactory response of first-line R-CHOP treatment in patients with follicular lymphoma with grade 1/2.

For follicular lymphoma (FL) with grade 1/2, the complete response (CR) rate of the first-line R-CHOP treatment was significantly low. In this study, we assessed the rationality of the administration of rituximab for FL patients with grade 1/2 based on concentration-response relationship analyses. Thus, we conducted a prospective pharmacokinetic (PK) study in 68 FL patients with grades 1-3 treated with R-CHOP at 21-day intervals. Plasma rituximab concentrations were quantified using ELISA and the population PK modeling was established with Phoenix® NLMETM. The first cycle trough concentration (C1-trough) of rituximab was a significant independent risk factor for achieving CR in matched-pair logistic regression analysis, rather than the concentrations in later cycles; the recommendatory minimum optimal C1-trough was 13.60 µg/mL. Patients with grade 1/2 had significantly lower C1-trough compared with grade 3 (12.21 µg/mL vs. 23.45 µg/mL, P < 0.001), only 30% patients with grade 1/2 could reach 13.60 µg/mL, compared with 91.67% in patients with grade 3, which was in accord with its unsatisfactory CR rates (43.33% vs. 76.32%). The stage indicating the tumor burden (the target) was a crucial influence factor for C1-trough, accounting for 40.70% of its variability, 70% patients with grade 1/2 were stage IV in this study, since the systemic therapy only started at the disseminated disease stage. The initial dose of 1800 mg was recommended by Monte Carlo simulation for patients with grade 1/2. In summary, low C1-trough accounted for low-grade FL's unsatisfactory CR rate, designing the first dosage of rituximab should be a very important component of individualized therapy for FL.

HDAC8 promotes the dissemination of breast cancer cells via AKT/GSK-3ß/Snail signals.

The mechanistic action of histone deacetylase 8 (HDAC8) in cancer motility, including epithelial-mesenchymal transition (EMT), remains largely undefined. We found that the expression of HDAC8 was upregulated in breast cancer (BC) cells and tissues as compared to the controls. Further, BC tissues had the highest values of HDAC8 expression among 31 kinds of cancers. Cellular study indicated that HDAC8 can positively regulate the dissemination and EMT of BC cells. It increased the protein stability of Snail, an important regulator of EMT, by phosphorylation of its motif 2 in serine-rich regions. There are 21 factors that have been reported to regulate the protein stability of Snail. Among them, HDAC8 can decrease the expression of GSK-3ß through increasing its Ser9-phosphorylation. Mass spectrum analysis indicated that HDAC8 interact with AKT1 to decrease its acetylation while increase its phosphorylation, which further increased Ser9-phosphorylation of GSK-3ß. The C-terminal of AKT1 was responsible for the interaction between HDAC8 and AKT1. Further, Lys426 was the key residue for HDAC8-regulated deacetylation of AKT1. Moreover, HDAC8/Snail axis acted as adverse prognosis factors for in vivo progression and overall survival (OS) rate of BC patients. Collectively, we found that HDAC8 can trigger the dissemination of BC cells via AKT/GSK-3ß/Snail signals, which imposed that inhibition of HDAC8 is a potential approach for BC treatment.

Targeted mRNA demethylation using an engineered dCas13b-ALKBH5 fusion protein.

Studies on biological functions of N6-methyladenosine (m6A) modification in mRNA have drawn significant attention in recent years. Here we describe the construction and characterization of a CRISPR-Cas13b-based tool for targeted demethylation of specific mRNA. A fusion protein, named dm6ACRISPR, was created by linking a catalytically inactive Type VI-B Cas13 enzyme from Prevotella sp. P5-125 (dPspCas13b) to m6A demethylase AlkB homolog 5 (ALKBH5). dm6ACRISPR specifically demethylates m6A of targeted mRNA such as cytochrome b5 form A (CYB5A) to increase its mRNA stability. It can also demethylate ß-catenin-encoding CTNNB1 mRNA that contains multiple m6A sites to trigger its translation. In addition, the dm6ACRISPR system incurs efficient demethylation of targeted epitranscriptome transcripts with limited off-target effects. Targeted demethylation of transcripts coding for oncoproteins such as epidermal growth factor receptor (EGFR) and MYC can suppress proliferation of cancer cells. Together, we provide a programmable and in vivo manipulation tool to study mRNA modification of specific genes and their related biological functions.

N6-methyladenosine regulates glycolysis of cancer cells through PDK4.

Studies on biological functions of N6-methyladenosine (m6A) modification in mRNA have sprung up in recent years. We find m6A can positively regulate the glycolysis of cancer cells. Specifically, m6A-sequencing and functional studies confirm that pyruvate dehydrogenase kinase 4 (PDK4) is involved in m6A regulated glycolysis and ATP generation. The m6A modified 5'UTR of PDK4 positively regulates its translation elongation and mRNA stability via binding with YTHDF1/eEF-2 complex and IGF2BP3, respectively. Targeted specific demethylation of PDK4 m6A by dm6ACRISPR system can significantly decrease the expression of PDK4 and glycolysis of cancer cells. Further, TATA-binding protein (TBP) can transcriptionally increase the expression of Mettl3 in cervical cancer cells via binding to its promoter. In vivo and clinical data confirm the positive roles of m6A/PDK4 in tumor growth and progression of cervical and liver cancer. Our study reveals that m6A regulates glycolysis of cancer cells through PDK4.