Application of NGS molecular classification in the diagnosis of endometrial carcinoma: A supplement to traditional pathological diagnosis.

OBJECTIVE: This study aims to demonstrate the advantages of NGS molecular classification in EC diagnosis and to assess whether molecular classification could be performed on curettage specimens and its concordance with subsequent hysterectomy specimens. METHODS: 80 patients with hysterectomy specimens and 35/80 patients with paired curettage specimens were stratified as POLE mut, MSI-H, TP53 wt, or TP53 abn group by NGS panel. Histotype, tumor grade, IHC results, and other pathological details were taken from original pathological reports. RESULTS: The correlation analysis of 80 patients with hysterectomy specimens between NGS molecular classification and clinicopathological characters displayed that the POLE mut group was associated with EEC (87.5%) and TP53 abn subtype was correlated to a later stage (Stage II-IV, 47.6%), G3 (76.2%), serous histology (61.9%) and myometrial invasion ≥50% (47.6%). A favorable concordance (31/32, 96.9%) was shown in MSI analysis and MMR IHC results, and the agreement rate of p53 IHC and TP53 mutation was 81.5% (53/65). Compared with the p53 IHC abnormal group, the TP53 mutation group had a higher correlation with high-risk factors. A high level of concordance (31/35, 88.0%) of NGS molecular classification was achieved between curettage specimens and hysterectomy specimens while grade and histotype (including unclassified group) from curettage specimens and hysterectomy specimens showed only moderate levels of agreement, 54.3% (19/35) and 68.6% (24/35), respectively. CONCLUSION: NGS molecular classification achieved on curettage samples showed high concordance with the final hysterectomy specimens, demonstrating superior to the conventional pathological assessment of grade and histotype and potential utilization in clinical practice.

PARP-inhibition reprograms macrophages toward an anti-tumor phenotype.

Poly(ADP)ribosylation inhibitors (PARPis) are toxic to cancer cells with homologous recombination (HR) deficiency but not to HR-proficient cells in the tumor microenvironment (TME), including tumor-associated macrophages (TAMs). As TAMs can promote or inhibit tumor growth, we set out to examine the effects of PARP inhibition on TAMs in BRCA1-related breast cancer (BC). The PARPi olaparib causes reprogramming of TAMs toward higher cytotoxicity and phagocytosis. A PARPi-related surge in NAD+ increases glycolysis, blunts oxidative phosphorylation, and induces reverse mitochondrial electron transport (RET) with an increase in reactive oxygen species (ROS) and transcriptional reprogramming. This reprogramming occurs in the absence or presence of PARP1 or PARP2 and is partially recapitulated by addition of NAD derivative methyl-nicotinamide (MNA). In vivo and ex vivo, the effect of olaparib on TAMs contributes to the anti-tumor efficacy of the PARPi. In vivo blockade of the "don't-eat-me signal" with CD47 antibodies in combination with olaparib improves outcomes in a BRCA1-related BC model.

De Novo mutation in Epidermal growth factor receptor (EGFR)-D761Y responding to third generation tyrosine kinase inhibitor Osimertinib: A case report.

INTRODUCTION: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Epidermal growth factor receptor (EGFR) mutations are the most common accurate gene targets. However, the lack of case reports or cohort studies on the exceptionally rare mutations limit the acquisition of deeper insights. PATIENT CONCERNS: A 76-year-old female nonsmoker presented to our hospital with a one-week disease history of cough accompanied by shortness of breath. DIAGNOSIS: Contrast-enhanced CT scan showed right pleural effusion with scattered inflammation and consolidation in the right upper lung. Tumor marker display showed obvious increased. Histopathology of the pulmonary mass combined with Immunohistochemical staining indicated lung adenocarcinoma. Contrast-enhanced magnetic resonance imaging suggested brain metastases. ECT scan showed bone metastasis. The patient was thus diagnosed as right lung adenocarcinoma of stage IV (cT3N3M1c). Next generation sequencing was performed to profile the mutation status of known oncogenic driver mutations, and only EGFR-D761Y in exon 19 (allelic frequency, AF: 0.53%) mutation was found. INTERVENTIONS: The patient was accordingly treated with the third generation EGFR-Epidermal growth factor receptor tyrosine kinase inhibitor (TKI) Osimertinib (80 mg, qd). Accompanied with whole brain radiotherapy (DT3000c Gy/10f) for brain metastases, technetium methylene diphosphonate injection was performed for bone metastases. OUTCOMES: The efficacy of the first-line Osimertinib treatment for 1 month was assessed as PR per RECIST version 1.1. The NSCLC patient harboring EGFR-D761Y mutation detected prior to the EGFR L858R mutation was benefited from the third-generation EGFR-TKI Osimertinib and had a worse prognosis than with other EGFR mutations according to data from previous case reports. CONCLUSIONS: This case reported a NSCLC patient with de novo mutation of EGFR-D761Y responding to third generation TKI Osimertinib.

The miR-378c-Samd1 circuit promotes phenotypic modulation of vascular smooth muscle cells and foam cells formation in atherosclerosis lesions.

MicroRNAs have emerged as key regulators in vascular diseases and are involved in the formation of atherosclerotic lesions. However, the atherosclerotic-specific MicroRNAs and their functional roles in atherosclerosis are unclear. Here, we report that miR-378c protects against atherosclerosis by directly targeting Sterile Alpha Motif Domain Containing 1 (Samd1), a predicted transcriptional repressor. miR-378c was strikingly reduced in atherosclerotic plaques and blood of acute coronary syndrome (ACS) patients relative to healthy controls. Suppression of miR-378c promoted vascular smooth muscle cells (VSMCs) phenotypic transition during atherosclerosis. We also reported for the first time that Samd1 prolonged immobilization of LDL on the VSMCs, thus facilitated LDL oxidation and subsequently foam cell formation. Further, we found that Samd1 contains predicted DNA binding domain and directly binds to DNA regions as a transcriptional repressor. Together, we uncovered a novel mechanism whereby miR-378c-Samd1 circuit participates in two key elements of atherosclerosis, VSMCs phenotypic transition and LDL oxidation. Our results provided a better understanding of atherosclerosis pathophysiology and potential therapeutic management by targeting miR-378c-Samd1 circuit.

Glycine cleavage system determines the fate of pluripotent stem cells via the regulation of senescence and epigenetic modifications.

Metabolic remodelling has emerged as critical for stem cell pluripotency; however, the underlying mechanisms have yet to be fully elucidated. Here, we found that the glycine cleavage system (GCS) is highly activated to promote stem cell pluripotency and during somatic cell reprogramming. Mechanistically, we revealed that the expression of Gldc, a rate-limiting GCS enzyme regulated by Sox2 and Lin28A, facilitates this activation. We further found that the activated GCS catabolizes glycine to fuel H3K4me3 modification, thus promoting the expression of pluripotency genes. Moreover, the activated GCS helps to cleave excess glycine and prevents methylglyoxal accumulation, which stimulates senescence in stem cells and during reprogramming. Collectively, our results demonstrate a novel mechanism whereby GCS activation controls stem cell pluripotency by promoting H3K4me3 modification and preventing cellular senescence.

Fatty acid synthesis is critical for stem cell pluripotency via promoting mitochondrial fission.

Pluripotent stem cells are known to display distinct metabolic phenotypes than their somatic counterparts. While accumulating studies are focused on the roles of glucose and amino acid metabolism in facilitating pluripotency, little is known regarding the role of lipid metabolism in regulation of stem cell activities. Here, we show that fatty acid (FA) synthesis activation is critical for stem cell pluripotency. Our initial observations demonstrated enhanced lipogenesis in pluripotent cells and during cellular reprogramming. Further analysis indicated that de novo FA synthesis controls cellular reprogramming and embryonic stem cell pluripotency through mitochondrial fission. Mechanistically, we found that de novo FA synthesis regulated by the lipogenic enzyme ACC1 leads to the enhanced mitochondrial fission via (i) consumption of AcCoA which affects acetylation-mediated FIS1 ubiquitin-proteasome degradation and (ii) generation of lipid products that drive the mitochondrial dynamic equilibrium toward fission. Moreover, we demonstrated that the effect of Acc1 on cellular reprogramming via mitochondrial fission also exists in human iPSC induction. In summary, our study reveals a critical involvement of the FA synthesis pathway in promoting ESC pluripotency and iPSC formation via regulating mitochondrial fission.

CUE domain-containing protein 2 promotes the Warburg effect and tumorigenesis.

Cancer progression depends on cellular metabolic reprogramming as both direct and indirect consequence of oncogenic lesions; however, the underlying mechanisms are still poorly understood. Here, we report that CUEDC2 (CUE domain-containing protein 2) plays a vital role in facilitating aerobic glycolysis, or Warburg effect, in cancer cells. Mechanistically, we show that CUEDC2 upregulates the two key glycolytic proteins GLUT3 and LDHA via interacting with the glucocorticoid receptor (GR) or 14-3-3ζ, respectively. We further demonstrate that enhanced aerobic glycolysis is essential for the role of CUEDC2 to drive cancer progression. Moreover, using tissue microarray analysis, we show a correlation between the aberrant expression of CUEDC2, and GLUT3 and LDHA in clinical HCC samples, further demonstrating a link between CUEDC2 and the Warburg effect during cancer development. Taken together, our findings reveal a previously unappreciated function of CUEDC2 in cancer cell metabolism and tumorigenesis, illustrating how close oncogenic lesions are intertwined with metabolic alterations promoting cancer progression.

miR-290/371-Mbd2-Myc circuit regulates glycolytic metabolism to promote pluripotency.

Enhanced glycolysis is a main feature of pluripotent stem cells (PSCs) and is proposed to be important for the maintenance and induction of pluripotency. The molecular mechanism underlying enhanced glycolysis in PSCs is not clear. Using Dgcr8-/- mouse embryonic stem cells (ESCs) that lack mature miRNAs, we found that miR-290 cluster of miRNAs stimulates glycolysis by upregulating glycolytic enzymes Pkm2 and Ldha, which are also essential for the induction of pluripotency during reprogramming. Mechanistically, we identified Mbd2, a reader for methylated CpGs, as the target of miR-290 cluster that represses glycolysis and reprogramming. Furthermore, we discovered Myc as a key target of Mbd2 that controls metabolic switch in ESCs. Importantly, we demonstrated that miR-371 cluster, a human homolog of miR-290 cluster, stimulates glycolysis to promote the reprogramming of human fibroblasts. Hence, we identified a previously unappreciated mechanism by which miR-290/371 miRNAs orchestrate epigenetic, transcriptional and metabolic networks to promote pluripotency in PSCs and during reprogramming.