31 research outputs found
Refractory microsatellite stable metastatic colorectal cancer with ERBB2/ERBB3 mutation may be preferred population for regorafenib plus PD-1 inhibitor therapy: a real-world study
BackgroundMicrosatellite stable (MSS) colorectal cancer (CRC) has been referred to as the ācold tumorā because of almost no response to antiāprogrammed death-1 (PD-1) antibody. A recent REGONIVO trial showed that regorafenib plus nivolumab had an encouraging efficacy in MSS metastatic CRC (mCRC). However, only a small subset of patients may benefit from the combination therapy. We aim to evaluate the efficacy and safety data of immune checkpoint inhibitors combined with regorafenib in refractory MSS mCRC and to discover biomarkers that can effectively stratify the beneficial patient population.MethodsWe retrospectively analyzed patients with MSS mCRC who received regorafenib combined with antiāPD-1 antibody therapy. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and status of gene mutation were reviewed and evaluated.ResultsTwenty-one patients received combination treatment. At a median treatment duration of 4 months, one patient achieved complete response, three patients achieved partial response, and two patients achieved stable disease as the best response. The ORR and DCR were 19% and 28.5% in the overall population, respectively. The median PFS was 4 months, and the median OS was 25 months. Only erbb2 receptor tyrosine kinase 2/erbb3 receptor tyrosine kinase 3 (ERBB2/ERBB3) mutation status was confirmed to be a potential predictive factor for effective treatment. In patients with ERBB2/ERBB3 mutation, ORR, DCR, and PFS exhibited significant improvements in comparison with that in wild-type patients. Grade 3 or higher treatment-related adverse events occurred in three patients (14.3%).ConclusionsRegorafenib in combination with PD-1 inhibitor provides a feasible treatment regimen for refractory MSS mCRC with tolerated toxicity. Patients with ERBB2/ERBB3 mutation may be the preferred population for this combination regimen
Prognostic significance of negative lymph node count in microsatellite instability-high colorectal cancer
Abstract Background Microsatellite instability-high (MSI-H) tumors, with elevated tumor mutational burden and expression of neoantigens, represent a distinct immune-activated subpopulation in colorectal cancer (CRC), characterized by strong lymph node reaction, locally advanced tumor and higher total lymph nodes harvested (TLN), but less metastatic lymph nodes and fewer incidence of III-IV stage. Host immune response to tumor and lymph nodes may be an important prognostic factor. However, N stage and LNR (Lymph-Node Ratio) have limitations in predicting the prognosis of MSI-H patients. Negative lymph node count (NLC) provided a more precise representation of immune activation status and extent of tumor metastasis. The study aims to detect prognostic significance of NLC in MSI-H CRC patients, and compare it with N stage, TLN and LNR. Methods Retrospective data of 190 consecutive MSI-H CRC patients who received curative resection were collected. Survival analyses were performed using the KaplanāMeier method. Clinicopathological variables including NLC, N stage, TLN and LNR were studied in univariate and multivariate COX regression analyses. ROC (receiver operating characteristic curve) and concordance index were employed to compare the differences in predictive efficacy between NLC, N stage, TLN and LNR. Results Patients with increased NLC experienced a significantly improved 5-years DFS and OS in KaplanāMeier analysis, univariate analysis, and multivariate analysis, independent of potential confounders examined. Increased NLC corresponded to elevated 5-years DFS rate and 5-years OS rate. AUC (area under curve) and concordance index of NLC in DFS and OS predicting were both significantly higher than N stage, TLN and LNR. Conclusions Negative lymph node is an important independent prognostic factor for MSI-H patients. Reduced NLC is associated with tumor recurrence and poor survival, which is a stronger prognostic factor than N stage, TLN and LNR
Organic biodegradable piezoelectric materials and their potential applications as bioelectronics
Biodegradable piezoelectrics represent an intriguing category of electroactive materials combining the mechanical-electrical coupling characteristics with a unique biodegradable feature that eliminates unnecessary materials retention and minimize associated infection risks. Here, we review the piezoelectric properties of representative organic biodegradable piezoelectric materials including amino acids, peptides, proteins, synthetic polymers and polysaccharides. Strategies to promote the piezoelectric activity are summarized, and recent progress in the utilization of biodegradable piezoelectric materials for bioelectronics is discussed, with perspectives and challenges provided at the end to enlighten possible future directions
Stepwise Adipogenesis of Decellularized Cellular Extracellular Matrix Regulates Adipose Tissue-Derived Stem Cell Migration and Differentiation
Microenvironmental factors can modulate the cellular status of adipose tissue-derived stem cells (ASCs). In response to microenvironmental changes, cells can remodel extracellular matrix (ECM) proteins, which play an important role in regulating cell behaviors. During adipogenic differentiation, ECM components secreted from ASCs remodel dramatically. To evaluate the role of stepwise adipogenesis-induced cellular secretion of ECM on the behavior of ASCs, we cultured ASCs in growth and adipogenic media, and ECM secreted from cells was characterized and decellularized. The ASCs were then reseeded on decellularized ECM (d-ECM) to determine the regulatory effects of ECM on cellular behaviors. During adipogenesis, cell-secreted ECM underwent remodeling characterized by conversion from fibronectin-rich ECM to laminin-rich ECM. The cellular status of ASCs was tested after reseeding on decellularized ECM. When reseeded on growth d-ECM, ASCs exhibited greater migration ability. In contrast, ASCs seeded on adipogenic d-ECM underwent adipogenic differentiation. In addition, integrin subunit Ī±v and integrins Ī±6 and Ī±7 were detected at significantly greater levels in ASCs cultured on growth and adipogenic d-ECM, respectively, suggesting that integrins play an important role in ASC migration and adipogenesis. This study demonstrated that stepwise adipogenesis-induced ECM production plays an important role in ASC migration and differentiation. In addition, this study provided a strategy to achieve precise regulation of stem cell function in adipose tissue engineering
Development and characterization of Triticum turgidum- Aegilops comosa and T. turgidum -Ae. markgrafii amphidiploids
Aegilops comosa and Ae. markgrafii are diploid progenitors of polyploidy species of Aegilops sharing M and C genomes, respectively. Transferring valuable genes/traits from Aegilops into wheat is an alternative strategy for wheat genetic improvement. The amphidiploids between diploid species of Aegilops and tetraploid wheat can act as bridges to overcome obstacles from direct hybridization and can be developed by the union of unreduced gametes. In this study, we developed seven Triticum turgidum ā Ae. comosa and two T. turgidum ā Ae. markgrafii amphidiploids. The unreduced gametes mechanisms, including first-division restitution (FDR) and single-division meiosis (SDM), were observed in triploid F1 hybrids of T. turgidum ā Ae. comosa (STM) and T. turgidum ā Ae. markgrafii (STC). Only FDR was observed in STC hybrids, whereas FDR or both FDR and SDM were detected in the STM hybrids. All seven pairs of M chromosomes of Ae. comosa and C chromosomes of Ae. markgrafii were distinguished by fluorescent in situ hybridization (FISH) probes pSc119.2 and pTa71 combinations with pTa-535 and (CTT)12/(ACT)7, respectively. Meanwhile, the chromosomes of tetraploid wheat and diploid Aegilops parents were distinguished by the same FISH probes. The amphidiploids possessed specific valuable traits such as multiple tillers, large seed size related traits, and stripe rust resistance that could be utilized in the genetic improvement of wheat.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Dedifferentiated human umbilical cord mesenchymal stem cell reprogramming of endogenous hSDF-1Ī± expression participates in neural restoration in hypoxic-ischemic brain damage rats
The transplantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) can promote hypoxic-ischemic brain damage (HIBD) nerve repair, but finding suitable seed cells to optimize transplantation and improve treatment efficiency is an urgent problem to be solved. In this study, we induced hUC-MSCs into dedifferentiated hUC-MSCs (De-hUC-MSCs), and the morphology, stem cell surface markers, proliferation and tri-directional differentiation ability of the De-hUC-MSCs and hUC-MSCs were detected. A whole-gene chip was utilized for genome cluster, gene ontology and KEGG pathway analyses of differentially expressed genes. De-hUC-MSCs were transplanted into HIBD rats, and behavioral experiments and immunofluorescence assays were used to assess the therapeutic effect. A lentivirus vector for human stromal cell-derived factor-1 (hSDF-1Ī±) was constructed, and the role of hSDF-1Ī± in the neuroprotective effect and mechanism of De-hUC-MSCs was verified. De-hUC-MSCs displayed similar cell morphology, stem cell surface marker expression, cell proliferation and even three-dimensional differentiation ability as hUC-MSCs but exhibited greater treatment potential in vivo. The reprogramming mechanism of hSDF-1Ī± participated in the dedifferentiation process. By successfully constructing a stable hSDF-1Ī± cell line, we found that De-hUC-MSCs might participate in nerve repair through the hSDF-1Ī±/CXCR4/PI3K/Akt pathway. De-hUC-MSCs reprogramming of endogenous hSDF-1Ī± expression may mediate the hSDF-1Ī±/CXCR4/PI3K/Akt pathway involved in nerve repair in HIBD rats
Regulation of the integrin Ī±VĪ²3- actin filaments axis in early osteogenic differentiation of human mesenchymal stem cells under cyclic tensile stress
Abstract Background Integrins are closely related to mechanical conduction and play a crucial role in the osteogenesis of human mesenchymal stem cells. Here we wondered whether tensile stress could influence cell differentiation through integrin Ī±VĪ²3. Methods We inhibited the function of integrin Ī±VĪ²3 of human mesenchymal stem cells by treating with c(RGDyk). Using cytochalasin D and verteporfin to inhibit polymerization of microfilament and function of nuclear Yes-associated protein (YAP), respectively. For each application, mesenchymal stem cells were loaded by cyclic tensile stress of 10% at 0.5Ā Hz for 2Ā h daily. Mesenchymal stem cells were harvested on day 7 post-treatment. Western blotting and quantitative RT-PCR were used to detect the expression of alkaline phosphatase (ALP), RUNX2, Ī²-actin, integrin Ī±VĪ²3, talin-1, vinculin, FAK, and nuclear YAP. Immunofluorescence staining detected vinculin, actin filaments, and YAP nuclear localization. Results Cyclic tensile stress could increase the expression of ALP and RUNX2. Inhibition of integrin Ī±VĪ²3 activation led to rearrangement of actin filaments and downregulated the expression of ALP, RUNX2 and promoted YAP nuclear localization. When microfilament polymerization was inhibited, ALP, RUNX2, and nuclear YAP nuclear localization decreased. Inhibition of YAP nuclear localization could reduce the expression of ALP and RUNX2. Conclusions Cyclic tensile stress promotes early osteogenesis of human mesenchymal stem cells via the integrin Ī±VĪ²3-actin filaments axis. YAP nuclear localization participates in this process of human mesenchymal stem cells. Video Abstrac