Dysregulation of pre-mRNA alternative splicing (AS) is closely associated with cancers. However, the relationships between the AS and classic oncogenes/tumor suppressors are largely unknown. Here we show that the deletion of tumor suppressor PTEN alters pre-mRNA splicing in a phosphatase-independent manner, and identify 262 PTEN-regulated AS events in 293T cells by RNA sequencing, which are associated with significant worse outcome of cancer patients. Based on these findings, we report that nuclear PTEN interacts with the splicing machinery, spliceosome, to regulate its assembly and pre-mRNA splicing. We also identify a new exon 2b in GOLGA2 transcript and the exon exclusion contributes to PTEN knockdown-induced tumorigenesis by promoting dramatic Golgi extension and secretion, and PTEN depletion significantly sensitizes cancer cells to secretion inhibitors brefeldin A and golgicide A. Our results suggest that Golgi secretion inhibitors alone or in combination with PI3K/Akt kinase inhibitors may be therapeutically useful for PTEN-deficient cancers.
Polygonatum cyrtonema Hua is a perennial herbaceous plant of the Polygonatum genus, belonging to the Liliaceae family, with significant medicinal and nutritional value. In China, this species is a traditional medicinal and edible herb with a long history of application and is widely appreciated by the people. However, as the demand for medicinal herbs continues to grow, excessive harvesting has led to the depletion of wild resources and the risk of genetic erosion. In addition, the chaotic cultivation of varieties and the lack of high quality germplasm resources have led to inconsistent quality of medical materials. Therefore, it is urgent to conduct genetic diversity evaluation of this species and establish a sound conservation plan. This study assessed the genetic diversity and population structure of 96 samples collected from seven regions in China using the simple sequence repeat (SSR) molecular marker technology. In this study, a total of 60 alleles (Na) were detected across the 10 polymorphic SSR markers used, with an average of 6.0 alleles generated per locus. The values of polymorphic information content (PIC) values ranged from 0.3396 to 0.8794, with an average value of 0.6430. The average value of the effective number of alleles (Ne) was 2.761, and the average value of the Shannon's information index (I) was 1.196. The population structure analysis indicates that the Polygonatum cyrtonema Hua germplasm can be classified into three subpopulations (JZ, QY, JD) at the molecular level, which corresponds to the previous subgroups identified based on individual plant phenotypic traits. Analysis of Molecular Variance (AMOVA) showed that 74% of the genetic variation was between individuals within populations in different regions. The phylogenetic analysis of the 96 germplasm samples divided them into three main populations. The QY and JD subpopulations are largely clustered together, which could be attributed to their mountainous distribution and the local climate environment. The genetic differentiation coefficient (Fst) value was low at 0.065, indicating relatively low population differentiation. The ratio of the genetic differentiation coefficient (Fst) between the JZ population and the other two populations (QY and JD) is much higher than the ratio between the QY and JD populations. Based on the clustering results and the ratio of the genetic differentiation coefficient (Fst), it can be inferred that the genetic relationship between the QY and JD subpopulations is closer, with a certain degree of genetic differentiation from the JZ subpopulation. This study supports the conservation of germplasm resources of Polygonatum cyrtonema Hua in China and provides new parental material for germplasm genetic improvement and breeding programs.
Abstract Objective In this study, we evaluated the difference of progression-free survival (PFS) and overall survival (OS) between extensive-stage small-cell lung cancer (ES-SCLC) patients who acquired partial response (PR) or complete remission (CR) after two cycles of first-line chemotherapy with the etoposide plus cisplatin (EP) regimen and those who acquired PR or CR after four or six cycles. Methods A total of 106 eligible patients treated with the EP chemotherapy regimen for two to six cycles, at The General Hospital of Shenyang Military Region (China) between November 2004 and May 2011, were enrolled in this study. RECIST version 1.1 was used for the evaluation of chemotherapy efficiency. We followed up all eligible patients every 4 weeks. All statistical data were analyzed by using SPSS 21.0 statistical package for Windows. Results After a median follow-up of 293 days (range, 62-1531 days), all patients had died by the cutoff date. Fifty-one patients acquired PR or CR after two cycles of chemotherapy; the median PFS reached 6.0 months (95% CI, 5.1-6.9), and the median OS was 10.5 months (95% CI, 8.6-12.4). Twenty-eight patients acquired PR or CR after four or six cycles; the median PFS was 4.8 months (95% CI, 4.4-5.2), and the median OS was 7.5 months (95% CI, 6.8-8.2). Both PFS and OS showed a statistical difference between the two groups. Conclusion ES-SCLC patients who acquired PR or CR after two cycles of the EP regimen as first-line therapy had longer PFS and OS than those who acquired PR or CR after four or six cycles.
Hypoxia leads to hypoxic pulmonary hypertension (HPH), causing right ventricular hypertrophy (RVH). RVH becomes a significant and nonnegligible public health issue in the world. In our study, we successfully established the HPH rat model and found that RVH happened in HPH, and then we observed an increased inflammation response in the heart tissue of HPH-induced RVH rats. Moreover, increased N-deacetylase-N-sulfotransferase-1 (NDST1) and decreased nuclear localized protein 1 (NULP1) were found in the heart tissue of HPH-induced RVH rats. An in vitro cell experiment showed that inhibition of NDST1 expression enhanced cell viability, reduced cell apoptosis, alleviated cardiomyocyte hypertrophy, decreased inflammation and increased phosphorylated AKT level, however, over-expression of NDST1 had opposite effects on these aspects. NULP1 reversed the effects of NDST1 on these regulations. Finally, we found that up-regulated NDST1 reduced NULP1 expression and down-regulated NDST1 increased NULP1 expression. Our study confirmed that inhibition of the NDST1/NULP1 pathway might contribute to the attenuation of HPH-induced RVH, and the mechanism may be related to the reduction of inflammation, cardiomyocyte apoptosis, and AKT phosphorylation.
Certain secretory proteins are known to be critical for maintaining the stemness of stem cells through autocrine signaling. However, the processes underlying the biogenesis, maturation, and secretion of these proteins remain largely unknown. Here we demonstrate that many secretory proteins produced by hematopoietic stem cells (HSCs) undergo exosomal maturation and release that is controlled by vacuolar protein sorting protein 33b (VPS33B). Deletion of VPS33B in either mouse or human HSCs resulted in impaired exosome maturation and secretion as well as loss of stemness. Additionally, VPS33B deficiency led to a dramatic delay in leukemogenesis. Exosomes purified from either conditioned medium or human plasma could partially rescue the defects of HSCs and leukemia-initiating cells (LICs). VPS33B co-existed in exosomes with GDI2, VPS16B, FLOT1, and other known exosome markers. Mechanistically, VPS33B interacted with the GDI2/RAB11A/RAB27A pathway to regulate the trafficking of secretory proteins as exosomes. These findings reveal an essential role for VPS33B in exosome pathways in HSCs and LICs. Moreover, they shed light on the understanding of vesicle trafficking in other stem cells and on the development of improved strategies for cancer treatment.
The random-pattern flap has a significant application in full mouth restoration (reconstructive surgery) and plastic surgery owing to an easy operation with no axial vascular restriction. However, distal necrosis after flap operation is still considered the most common complication which makes it the Achilles heel in the clinical application of random-pattern flaps. A Chinese medicinal herb named gastrodin is an effective active ingredient of Gastrodia. Herein, the existing study explored the significant potential of gastrodin on flap survival and its underlying mechanism. Our obtained results show that gastrodin will significantly improve flap survival, reduce tissue edema, and increase blood flow. Furthermore, our studies reveal that gastrodin can promote angiogenesis and reduce the apoptotic process as well as oxidative stress. The results of immunohistochemistry and immunoblotting revealed that gastrodin has a role in the elevation of autophagy flux which results in induced autophagy. The use of 3MA (3-methyladenine) for the inhibition of induced autophagy significantly weakened the underlying benefits of gastrodin treatment. Taken together, our obtained results confirmed that gastrodin is an effective drug that can considerably promote the survival rate of flaps (random pattern) via enhancing autophagy. Enhanced autophagy is correlated with the elevation of angiogenesis, reduced level of oxidative stress, and inhibition of cell apoptosis.