Arabidopsis SMO2 modulates ribosome biogenesis by maintaining the RID2 abundance during organ growth.

Ribosome biogenesis is a process of making ribosomes that is tightly linked with plant growth and development. Here, through a suppressor screen for the smo2 mutant, we found that lack of a ribosomal stress response mediator, ANAC082 partially restored growth defects of the smo2 mutant, indicating SMO2 is required for the repression of nucleolar stress. Consistently, the smo2 knock-out mutant exhibited typical phenotypes characteristic of ribosome biogenesis mutants, such as pointed leaves, aberrant leaf venation, disrupted nucleolar structure, abnormal distribution of rRNA precursors, and enhanced tolerance to aminoglycoside antibiotics that target ribosomes. SMO2 interacted with ROOT INITIATION DEFECTIVE 2 (RID2), a methyltransferase-like protein required for pre-rRNA processing. SMO2 enhanced RID2 solubility in Escherichia coli and the loss of function of SMO2 in plant cells reduced RID2 abundance, which may result in abnormal accumulation of FIBRILLARIN 1 (FIB1) and NOP56, two key nucleolar proteins, in high-molecular-weight protein complex. Taken together, our results characterized a novel plant ribosome biogenesis factor, SMO2 that maintains the abundance of RID2, thereby sustaining ribosome biogenesis during plant organ growth.

Efficacy and Safety of Drug-Eluting Beads Bronchial Arterial Chemoembolization in Treating Patients with Lung Cancer Who Were Complicated with Hemoptysis.

Background: This study explored the effectiveness and safety of drug-eluting beads bronchial arterial chemoembolization (DEB-BACE) in patients with lung cancer who were complicated with hemoptysis. Materials and Methods: In total, 11 patients with lung cancer who were complicated with hemoptysis and underwent DEB-BACE treatment were analyzed. Clinical success was defined as no hemoptysis or reduction of hemoptysis volume >50% after treatment. Hemoptysis recurrence was recorded, and overall survival (OS) was calculated. Results: After DEB-BACE treatment, the clinical and technical success was 100%: in detail, 10 (90.0%) patients presented with no hemoptysis and 1 (9.1%) patient exhibited a reduction of hemoptysis volume >50%. Regarding the prognosis, 1 (9.1%) patient had hemoptysis recurrence at 46 d after DEB-BACE treatment. Furthermore, 4 (36.4%) patients died (1 [9.1%] patient died of nonhemoptysis asphyxia; 1 [9.1%] patient died of massive gastrointestinal hemorrhage; 1 [9.1%] patient died of respiratory failure; and 1 [9.1%] patient died of hemoptysis recurrence). Additionally, the mean OS in total patients was 14.2 (95% confidence interval: 8.2-20.3) months. As to adverse events, 1 (9.1%) patient showed high fever, 2 (18.2%) patients exhibited low fever, and 1 (9.1%) patient suffered from chest pain. Conclusions: DEB-BACE can be considered an effective and safe treatment in treating hemoptysis in patients with lung cancer.

Sintilimab combined with apatinib plus capecitabine in the treatment of unresectable hepatocellular carcinoma: A prospective, open-label, single-arm, phase II clinical study.

Objective: To evaluate the efficacy and safety of sintilimab combined with apatinib plus capecitabine in the treatment of unresectable hepatocellular carcinoma (HCC) to provide a more effective first-line treatment for patients with advanced HCC. Methods: This open-label, prospective, phase II study included patients with unresectable HCC who did not receive systematic treatment. The patients were treated with sintilimab (200 mg, intravenous drip, once every 3 weeks) combined with apatinib (250 mg, oral administration, once a day) plus capecitabine (1000 mg/m2, twice a day; after 2 weeks of oral administration, the drug was stopped for 1 week; course of treatment, 3 weeks). The primary endpoint was the objective response rate (ORR). The secondary endpoints included disease control rate (DCR), progression-free survival (PFS), duration of response (DoR), overall survival (OS), and safety. Results: Forty-seven patients (1 lost to follow-up) were enrolled in the study. As of March 1, 2022, the ORR and DCR were 50.0% (95% CI: 34.9-65.1%) and 91.3% (95% CI: 79.2-97.6%), respectively, after blind, independent imaging evaluation. The median follow-up time was 18.7 months (95% CI: 17.2-20.2 months). The median PFS was 9.0 months (95% CI: 7.1-10.9 months). The median DoR was 10.8 months (95% CI: 4.8-16.8 months). The median OS was not reached, and the 1-year OS rate was 71.7% (95% CI: 56.5-84.0%). Only 28.3% (13/46) of patients had grade 3/4 treatment-related adverse events. Conclusion: Sintilimab combined with apatinib plus capecitabine has good safety and anti-tumor activity as a first-line treatment for unresectable HCC. This is worthy of further multi-center, prospective, randomized, large-sample clinical studies. Clinical Trial Registration: https://ClinicalTrials.gov, identifier NCT04411706.

Toripalimab plus chemotherapy in treatment-naïve, advanced esophageal squamous cell carcinoma (JUPITER-06): A multi-center phase 3 trial.

Platinum-based chemotherapy is the standard first-line treatment for advanced esophageal squamous cell carcinoma (ESCC). In this phase 3 study (ClinicalTrial.gov: NCT03829969), 514 patients with treatment-naïve advanced ESCC were randomized (1:1) to receive toripalimab or placebo in combination with paclitaxel plus cisplatin (TP) every 3 weeks for up to 6 cycles, followed by toripalimab or placebo maintenance. At the prespecified final analysis of progression-free survival (PFS), a significant improvement in PFS is observed for the toripalimab arm over the placebo arm (hazard ratio [HR] = 0.58; 95% CI, 0.46-0.74; p < 0.0001). The prespecified interim analysis of overall survival (OS) also reveals a significant OS improvement for patients treated with toripalimab plus TP over placebo plus TP (HR = 0.58; 95% CI, 0.43-0.78; p = 0.0004). The incidences of grade ≥3 treatment-emergent adverse events are similar between the two arms. Toripalimab plus TP significantly improves PFS and OS in patients with treatment-naïve, advanced ESCC, with a manageable safety profile.

The Silence of PSMC6 Inhibits Cell Growth and Metastasis in Lung Adenocarcinoma.

The proteasome has been validated as an anticancer drug target, while the role of a subunit of proteasome, PSMC6, in lung adenocarcinoma (LUAD) has not been fully unveiled. In this study, we observed that both the RNA and protein of PSMC6 were highly upregulated in LUAD compared with the adjacent normal tissues. Moreover, a high PSMC6 expression was associated with poor prognosis. In accordance with this finding, PSMC6 was associated with poor tumor differentiation. Furthermore, the silence of PSMC6 by small interference RNAs (siRNAs) could significantly inhibit cell growth, migration, and invasion in lung cancer cell lines, suggesting that PSMC6 might serve as a promising therapeutic target in LUAD. To further explore the molecular mechanism of PSMC6 in LUAD, we observed that the proteasome subunits, such as PSMD10, PSMD6, PSMD9, PSMD13, PSMB3, PSMB1, PSMA4, PSMC1, PSMC2, PSMD7, and PSMD14, were highly correlated with PSMC6 expression. Based on the gene set enrichment analysis, we observed that these proteasome subunits were involved in the degradation of AXIN protein. The correlation analysis revealed that the positively correlated genes with PSMC6 were highly enriched in WNT signaling-related pathways, demonstrating that the PSMC6 overexpression may activate WNT signaling via degrading the AXIN protein, thereby promoting tumor progression. In summary, we systematically evaluated the differential expression levels and prognostic values of PSMC6 and predicted its biological function in LUAD, which suggested that PSMC6 might act as a promising therapeutic target in LUAD.

miR-34a inhibits esophageal squamous cell carcinoma progression via regulation of FOXM1.

Downregulation of microRNA-34a (miR-34a) has frequently been observed in esophageal squamous cell carcinoma (ESCC). However, the underlying role and molecular mechanism of miR-34a in ESCC remains largely unknown. In the current study, it was demonstrated that miR-34a was downregulated and forkhead box M1 (FOXM1), a target gene of miR-34a, was upregulated in ESCC tumor tissues. Overexpression of miR-34a decreased FOXM1 mRNA and protein expression in the ESCC cell lines tested (TE-1 and TE-8). Inhibition of miR-34a increased FOXM1 mRNA and protein levels in human esophageal epithelial cells (HEEC). In addition, miR-34a mimics reduced the relative luciferase activity of ESCC cells transfected with FOXM1 3'UTR-WT, but not FOXM1 3'UTR-Mut. The CCK8 assay and scratch wound healing assay showed that overexpression of miR-34a induced inhibition of cell proliferation and cell migration. Additionally, transfection with miR-34a mimics reduced the expression of key genes involved in cell migration (MMP2 and MMP9) in ESCC cells. Thus, the present data demonstrated that miR-34a suppressed ESCC progression by directly targeting FOXM1.

Do aeration conditions affect arsenic and phosphate accumulation and phosphate transporter expression in rice (Oryza sativa L.)?

Widespread contamination of rice with arsenic (As) has revealed a major exposure pathway to humans. The present study aimed to investigate the effects of oxygen in the rhizosphere on phosphate (P) transporter (for arsenate transportation) expressions, on As and P accumulation and As speciation in four rice genotypes. Oxygenation marginally increased root and shoot length. Total As concentrations in rice roots were dramatically reduced following aeration compared to stagnant treatments (p < 0.001). Aeration treatments significantly increased arsenate while reducing arsenite concentrations in roots (p < 0.001). Root arsenite concentrations were 1.5-2.5 times greater in stagnant than in aeration treatments. Total P concentrations in rice roots were dramatically increased following aeration compared to stagnant treatments. The relative abundance of phosphate transporter (inorganic phosphate transporter and phosphate/H+ symporter family protein) expressions showed downregulation in aeration treatments, particularly for SY-9586, XWX-17, and XWX-12 in inorganic phosphate transporter expressions and XWX-17 in phosphate/H+ symporter family protein expression (p < 0.05). The relative abundance of phosphate carrier protein expressions were relatively higher than the other phosphate transporters, showing upregulation in aeration treatments.

Identification of differentially expressed molecular functions associated with breast cancer using Gibbs sampling.

The aim of the present study was to identify differentially expressed molecular functions (DEMFs) for breast cancer using the Gibbs sampling approach. Molecular functions (MFs) were obtained on the basis of the Bayesian Approach for Geneset Selection package. Subsequently, MFs were converted into Markov chains (MCs) prior to calculating their probabilities, utilizing the MC Monte Carlo algorithm. DEMFs were identified with probabilities ≥0.8 and the gene compositions were studied. Finally, a co-expression network was constructed via the empirical Bayes method and a pathway enrichment analysis of genes in DEMFs was performed. A total of 396 MFs were identified and all transformed to MCs. With the threshold, 2 DEMFs (structural molecule activity and protein heterodimerization activity) were obtained. The DEMFs were comprised of 297 genes, 259 of which were mapped to the co-expression network. These 297 genes were identified to be enriched in 10 pathways, and ribosome was the most significant pathway. The results of the present study revealed 2 DEMFs (structural molecule activity and protein heterodimerization activity) which may be associated with the pathological molecular mechanisms underlying breast cancer, based on Gibbs sampling.

Downregulation of Bmi-1 is associated with suppressed tumorigenesis and induced apoptosis in CD44⁺ nasopharyngeal carcinoma cancer stem-like cells.

Bmi-1 (B-cell-specific Moloney murine leukemia virus insertion site 1) is a member of the Polycomb group gene (PcG) family, which is involved in the proliferation, migration and tumorigenesis of several types of cancer stem cells (CSCs). However, its precise role and mechanism in CD44+ nasopharyngeal carcinoma (NPC) cancer stem-like cells (CSC-LCs) remain poorly understood. In our previous study, we successfully silenced Bmi-1 by short hairpin RNA (shRNA) in CD44+ NPC CSC-LCs and obtained stable Bmi-1 knockdown (KD) cell lines. In the present study, we tested the cell proliferation by CCK-8 assay and apoptosis by flow cytometry. Scratch wound healing assay, together with Transwell migration and invasion assays were used to measure the migration and invasion capacity. We further evaluated the tumorigenicity of CD44+ NPC CSC-LCs transfected with Bmi-1 shRNA in vivo. Based on our results, knockdown of Bmi-1 by shRNA resulted in the inhibition of tumor proliferation, migration and invasion in vitro, followed by cell apoptosis. In addition, our results preliminarily demonstrated that inhibition of Bmi-1 expression by shRNA increased tumor apoptosis through the p16INK4a-p14ARF-p53 pathway. Bmi-1 silencing in CD44+ NPC CSC-LCs also resulted in the failure to develop tumors in vivo. These results provide important insights into the role of Bmi-1 in the occurrence and development of NPC. Based on our findings, regulation of Bmi-1 in CD44+ NPC CSC-LCs may provide a potential molecular target for the therapy of NPC, and targeted silencing of Bmi-1 by shRNA may have clinical future implications in NPC therapy.

Effect of shRNA-Mediated Gene Silencing of Bmi-1 Expression on Chemosensitivity of CD44+ Nasopharyngeal Carcinoma Cancer Stem-Like Cells.

In this study, we investigate the effect of short hairpin RNA-mediated gene silencing of Bmi-1 expression on chemosensitivity of CD44(+) nasopharyngeal carcinoma cancer stem-like cells. The sequence-specific short hairpin RNA lentivirus targeting at human Bmi-1 was synthesized and used to infect CD44(+) nasopharyngeal cells that were sorted by flow cytometry. We also employed flow cytometry to detect transfection efficiency. Real-time polymerase chain reaction was used to detect Bmi-1 and its downstream repressor genes p16(INK4a) and p14(ARF) messenger RNA, while each protein expression level of Bmi-1, p16(INK4a), p14(ARF), and p53 was confirmed by Western blotting protocol. Tumor spheroid assay was used to evaluate the self-renewal capacity. 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay and colony formation assay were applied to detect proliferation capacity and colony-forming capacity under different concentrations of chemotherapeutic drugs 5-fluorouracil or cisplatin. Transwell cell migration and invasion assay were employed to observe migration and invasion capacity after cells were exposed to cisplatin for 24 hours. The constructed short hairpin RNA lentivirus targeting Bmi-1 gene successfully infected into the CD44(+) nasopharyngeal carcinoma cells and effectively inhibited the Bmi-1 messenger RNA and protein expression level, while the expression level of Bim-1 target genes, p16(INK4a), p14(ARF), and p53 was significantly increased (P < .05). Notably, the proliferation, colony formation, migration, and invasion capabilities of the sequence-specific short hairpin RNA lentivirus-infected CD44(+) nasopharyngeal carcinoma cells reduced significantly under chemotherapeutic treatments (P < .05). Our results indicated that Bmi-1 may play an important role in the chemosensitivity of CD44(+) nasopharyngeal carcinoma cancer stem-like cells. Bmi-1 may be a potential new target for the treatment of nasopharyngeal carcinoma displaying chemotherapy resistance.

[Effect of gene silencing of Bmi-1 on proliferation regulation of CD44+ nasopharyngeal carcinoma cancer stem-like cells].

OBJECTIVE: To investigate the effect of gene silencing of Bmi-1 on proliferation regulation of CD44+ nasopharyngeal carcinoma cancer stem-like cells (CSC-LCs). METHOD: The sequence-specific short hairpin RNA lentivirus targeting at human Bmi-1 gene (LV-Bmi-1shRNA) was constructed and was used to infect CD44+ nasopharyngeal carcinoma cells which were sorted by flow cytometry. A lentiviral which included a random sequence was also designed to serve as a negative control. We employed fluorescence microscope and flow cytometry to detect infection efficiency; real-time PCR was used to detect Bmi-1 and its downstream gene while each protein expression level was confirmed by western blotting protocol; CCK-8 proliferation assay was applied to measure proliferation capacity; tumor spheroid assay was used to evaluate the self-renewal capacity. Colony formation assay was used to measure cell colony formation capability; flow cytometry analyzed cell cycle distribution. RESULT: The constructed LV-Bmi-1shRNA successfully infected into the CD44+ nasopharyngeal carcinoma cells. The infection efficiency could reach above 95%; LV-Bmi-lshRNA effectively inhibited Bmi-1 mRNA and protein expression, while the downstream gene p16INK4a and p14ARF mRNA as well as protein expression level were upregulated (P < 0.05). Notablely, the proliferation, colony formation, self-renewal capabilities of the experimental group decreased significantly (P < 0.05). In addition, the cell cycle arrested at the G0-G1 phase. CONCLUSION: Gene silencing of Bmi-1 inhibited the proliferation, colony formation and self-renewal capabilities of the CD44+ nasopharyngeal carcinoma CSC-LCs, inhibited the cell cycle processes, which may mediate through Bmi1-p16INK4a/p14ARF-p53 pathway. Our experimental results indicated that Bmi-1 gene may play an important role in the maintenance of the stem cell-like characteristics of CD44+ nasopharyngeal carcinoma cells. Bmi-1 gene may be a potential new target for the treatment of nasopharyng al carcinoma in the future.

ShRNA targeting Bmi-1 sensitizes CD44⁺ nasopharyngeal cancer stem-like cells to radiotherapy.

Accumulating evidence indicates that cancer stem cells (CSCs) are involved in resistance to radiation therapy (RT). Bmi-1, a member of the Polycomb family of transcriptional repressors, is essential for maintaining the self-renewal abilities of stem cells and overexpression of Bmi-1 correlates with cancer therapy failure. Our previous study identified that the CD44+ nasopharyngeal cancer (NPC) cells may be assumed as one of markers of nasopharyngeal carcinoma cancer stem cell-like cells (CSC-LCs) and Bmi-1 is overexpressed in CD44+ NPC. In the present study, we used RNA interference technology to knock down the expression of Bmi-1 in CD44+ NPC cells, and then measured the radiation response by clonogenic cell survival assay. DNA repair was monitored by γH2AX foci formation. Bmi-1 downstream relative gene and protein expression of p16, p14, p53 were assessed by western blotting and real-time PCR. Cell cycle and apoptosis were detected by flow cytometry assays. We found that Bmi-1 knockdown prolonged G1 and enhanced the radiation-induced G2/M arrest, inhibited DNA damage repair, elevated protein p16, p14 and p53 expression, leading to increased apoptosis in the radiated CD44+ cells. These data suggest that Bmi-1 downregulation increases the radiosensitivity to CD44+ NPC CSC-LCs. Bmi-1 is a potential target for increasing the sensitivity of NPC CSCs to radiotherapy.

Identification of cancer stem-like CD44+ cells in human nasopharyngeal carcinoma cell line.

BACKGROUND AND AIMS: Recent studies suggest that cancer stem cells (CSC) may be responsible for tumorigenesis and contribute to some individuals' resistance to cancer therapy. Although research is rapidly advancing in this field, to our knowledge there are few published reports about the CSC in human nasopharyngeal carcinoma (NPC). We undertook this study to separate, expand, and explore the biological features of CD44+ stem-like cancer cells from the human NPC SUNE-1 5-8F cell line. METHODS: Immunocytochemistry and flow cytometry were used to detect the expression of CD44 in SUNE-1 5-8F. Fluorescence-activated cell sorting was applied to purify CD44+ cells. MTT assay or clone formation assay was used to detect the differences of CD44+ and CD44- cells in proliferation, differentiation, radiosensitivity and chemosensitivity in vitro. The expression of stem cell markers Oct-4 and Bmi-1 was examined by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: CD44 was positively expressed in ∼52.5% of NPC SUNE-1 5-8F cell line. Regardless of serum-free medium and serum medium culture conditions, freshly sorted CD44+ cells showed stronger proliferative capacity than CD44- and unsorted cells. The expression levels of Bmi-1 and Oct-4 mRNA in CD44+ cells were significantly higher than CD44- cells. After 2 Gy radiation, the average clone formation efficiency for CD44+ and CD44- cells was 22.17 ± 6.65% and 11.50 ± 5.00%, respectively (p <0.05). After cisplatin and docetaxel treatment with the same drug concentration, CD44+ cells showed a higher survival rate compared with CD44- cells. CONCLUSIONS: CD44+ cells have the biological characteristics of tumor stem cell and may be assumed as one of the markers of NPC tumor stem cells.

Clinical effect of erlotinib as first-line treatment for Asian elderly patients with advanced non-small-cell lung cancer.

PURPOSE: To evaluate the efficacy and toxicities of erlotinib as first-line treatment for Asian elderly patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Untreated patients with advanced NSCLC were included in this study; erlotinib was orally administered at a dose of 150 mg daily until disease progression or intolerable toxicity or for other reasons. RESULTS: A total of 35 patients were enrolled. Patient characteristics were as follows: mean age 75.6 years (ranged 70-81 years), 24 (68.6%) male, 16 (45.7%) former or current smokers, 13 (37.1%) adenocarcinoma, 18 (51.4%) squamous cell carcinoma and 4 (11.4%) bronchioloalveolar carcinoma. Out of 35 patients, 1 CR, 16 PR and 10 SD, resulting in an overall response rate (CR + PR) of 48.6% and disease control rate (DCR = CR + PR + SD) of 77.1%. The median TTP was 6.4 months, and the median OS was 12.7 months. The CBR was 80%, and the 1-year survival rate was 48.6%. The most common adverse event (AE) was mild skin rash and diarrhea (CTC AE 1/2). Among them, the female never smokers with a non-squamous cell carcinoma histology was superior to the male smokers with a squamous cell carcinoma in disease control rate, with significant differences (P < 0.05). CONCLUSION: The results suggest that erlotinib monotherapy is an effective and well-tolerated treatment option for Asian elderly patients with advanced NSCLC.

[Effects of celecoxib on the proliferation and apoptosis of human nasopharyngeal carcinoma cell line CNE-2].

OBJECTIVE: To detect the effect of Celecoxib on the proliferation and apoptosis of human nasopharyngeal carcinoma cell line CNE-2. METHOD: The growth inhibition rate of CNE-2 by Celecoxib was evaluated with MTT method. Apoptosis related morphology changes were observed with transmission electron microscopy (TEM). The cell cycle and apoptosis were measured with flow cytometric method (FCM). Apoptotic index (AI) was counted by the TDT-mediated dUTP-biotin nick end-labeling (TUNEL) assay. RESULT: The growth of CNE-2 cell was inhibited by celecoxib in a dose-and time-dependent manner. Apoptosis with nuclear chromatin condensation, cell shrinkage, periplasm loss and the formation of apoptotic bodies was observed with TEM. Apoptotic rates of CNE-2 cells treated with 80 and 100 micromol/L celecoxib were (10.47+/-0.18)% and (20.17+/-0.55)% respectively, significantly higher than those of the control group (1.57+/-0.27)% with FCM. The percentage of G0/G1 phase cells increased, whereas the S and G2/M phases cells decreased in a dose-dependent manner after the treatment. TUNEL assay showed that the apoptosis ratio (AI) of CNE-2 treated with Celecoxib was higher than control group (P<0.01). CONCLUSION: Celecoxib can inhibit the growth of human nasopharyngeal carcinoma cell line CNE-2 and induce the cell apoptosis, which may be related to blocking the cell cycle progress of CNE-2 cells.