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Abstract Purpose To explore the function and regulatory mechanism of IFITM3 in mouse neural retinal progenitor cells (mNRPCs), which was found to be very important not only in the development of the retina in embryos but also in NRPCs after birth. Methods Published single-cell sequencing data were used to analyze IFITM3 expression in mNRPCs. RNA interference was used to knock down the expression of IFITM3. CCK-8 assays were used to analyze cell viability. RNA-seq was used to assess mRNA expression, as confirmed by real-time quantitative PCR, and immunofluorescence assays and western blots were used to validate the levels of relative proteins, and autophagy flux assay. Lysosomal trackers were used to track the organelle changes. Results The results of single-cell sequencing data showed that IFITM3 is highly expressed in the embryo, and after birth, RNA-seq showed high IFITM3 expression in mNRPCs. Proliferation and cell viability were greatly reduced after IFITM3 was knocked down. The cell membrane system and lysosomes were dramatically changed, and lysosomes were activated and evidently agglomerated in RAMP-treated cells. The expression of LAMP1 was significantly increased with lysosome agglomeration after treatment with rapamycin (RAMP). Further detection showed that SQSTM1/P62, HSC70 and LAMP-2A were upregulated, while no significant difference in LC3A/B expression was observed; no autophagic flux was generated. Conclusion IFITM3 regulates mNRPC viability and proliferation mainly through chaperone-mediated autophagy (CMA) but not macroautophagy (MA). IFITM3 plays a significant role in maintaining the homeostasis of progenitor cell self-renewal by sustaining low-level activation of CMA to eliminate deleterious factors in cells.

Colorectal cancer (CRC) is the most common malignancy worldwide, and its underlying molecular mechanisms remain largely unexplored. Accumulating evidences indicate cancer-associated fibroblasts (CAFs), abundant stromal cell population in the tumor microenvironment, play a key role in tumor development. Herein, we have successfully isolated CAFs and paired normal fibroblasts (NFs) from colorectal cancer tissues (n=10). By using a multiplex cytokine profiling assay, we have identified IL-6 as a major cytokine released by CAFs. Co-culturing of CAFs with CRC cell lines HCT116 or SW480 increases IL-6 release, and the secretion by CAFs can be further enhanced under hypoxia. By using the CCK-8 assay, we have found that HCT116 or SW480 cells treated with culture medium from CAFs, IL-6, or hypoxia showed a significant cell growth compared to control cells (p<0.01). Mechanistically, we have found that hypoxia could enhance the effect of the IL-6/STAT3 signaling on CRC cells, in part, through HIF-1α targeting PKM2. In conclusion, our data clearly proposes the interconnected mechanisms for constitutive activation of STAT3 signal by CAFs-derived IL-6 under hypoxia in colorectal cancer. The pharmacological inhibition of STAT3, PKM2, or HIF-1α can significantly reduce the oncogenic effect of IL-6, providing a potential therapeutic target for CRC patients. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a common primary liver cancer with a high incidence and mortality. Members of the growth-arresting-specific 2 (GAS2) family are involved in various biological processes in human malignancies. To date, there is only a limited amount of information available about the expression profile and clinical importance of GAS2 family in HCC. In this study, we found that GAS2L1 and GAS2L3 were distinctly upregulated in HCC specimens compared to non-tumor specimens. Pan-cancer assays indicated that GAS2L1 and GAS2L3 were highly expressed in most cancers. The Pearson's correlation revealed that the expressions of GAS2, GAS2L1 and GAS2L2 were negatively associated with methylation levels. Survival assays indicated that GAS2L1 and GAS2L3 were independent prognostic factors for HCC patients. Immune cell infiltration analysis revealed that GAS2, GAS2L1 and GAS2L3 were associated with several immune cells. Finally, we confirmed that GAS2L1 was highly expressed in HCC cells and its knockdown suppressed the proliferation of HCC cells. Taken together, our findings suggested the expression patterns and prognostic values of GAS2 members in HCC, providing insights for further study of the GAS2 family as sensitive diagnostic and prognostic markers for HCC. [ABSTRACT FROM AUTHOR]

Metastasis is one of the leading causes of cancer-related deaths. A comprehensive comparison of the differences between primary and metastatic cancers within the same organ can aid in understanding the growth mechanisms of cancer cells at metastatic sites, thereby helping to develop more effective targeted treatment strategies. Primary liver cancer is one of the most common types of cancer, and the liver is also one of the main metastatic sites. In this paper, we utilize single-cell RNA-Seq data to compare primary liver cancer and colorectal liver metastases from multiple perspectives, including cell types and proportions, activity of various cell types, cell–cell communication, mRNA expression differences within the same types of cells, key factors associated with cell proliferation, etc. Our analysis results show the following: (i) Compared to primary tissue, metastatic tissue contains more cytotoxic T cells and exhausted T cells, and it retains some specific characteristics of the primary site. (ii) Cells of the same type exhibit functional differences between primary and metastatic cancers, with metastatic cancer cells showing lower metabolism levels and immune cells exhibiting stronger immune activity. (iii) Interactions between monocytes and hepato-associated cells are strong in primary cancer, while depleted T cells frequently communicate with hepatocytes in metastatic cancer. (iv) Proliferation-related genes in primary and metastatic cancers are mainly involved in cell energy supply and basic metabolism activity, respectively. [ABSTRACT FROM AUTHOR]

Background: Histone methylations are generally considered to play an important role in multiple cancers by regulating cancer-related genes. Aims: This study aims to investigate the effects of H3K27me3-mediated inactivation of tumor suppressor gene SFRP1 and its function in esophageal squamous cell carcinoma (ESCC). Methods: We performed ChIP-seq on H3K27me3-enriched genomic DNA fragments in ESCC cells to screen out tumor suppressor genes that may be regulated by H3K27me3. ChIP-qPCR and Western blot were employed to explore the regulating mechanisms between H3K27me3 and SFRP1. Expression level of SFRP1 was assessed by quantitative real-time polymerase chain reaction (q-PCR) in 29 pairs of ESCC surgical samples. SFRP1 function in ESCC cells were detected by cell proliferation assay, colony formation assay and wound-healing assay. Results: Our results indicated that H3K27me3 was widely distributed in the genome of ESCC cells. Specifically, we found that H3K27me3 deposited on the upstream region of SFRP1 promoter and inactivated SFRP1 expression. Furthermore, we found SFRP1 was significantly down-regulated in ESCC tissues compared with the adjacent non-tumor tissues, and SFRP1 expression was significantly associated with TNM stage and lymph node metastasis. In vitro cell-based assay indicated that over-expression of SFRP1 significantly suppressed cell proliferation and negatively correlated with the expression of β-catenin in the nucleus. Conclusions: Our study revealed a previously unrecognized finding that H3K27me3-mediated SFRP1 inhibit the cell proliferation of ESCC through inactivation of Wnt/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

Curcin and Curcin C, both of the ribosome-inactivating proteins of Jatropha curcas, have apparent inhibitory effects on the proliferation of osteosarcoma cell line U20S. However, the inhibitory effect of the latter is 13-fold higher than that of Curcin. The mechanism responsible for the difference has not been studied. This work aimed to understand and verify whether there are differences in entry efficiency and pathway between them using specific endocytosis inhibitors, gene silencing, and labeling techniques such as fluorescein isothiocyanate (FITC) labeling. The study found that the internalization efficiency of Curcin C was twice that of Curcin for U2OS cells. More than one entering pathway was adopted by both of them. Curcin C can enter U2OS cells through clathrin-dependent endocytosis and macropinocytosis, but clathrin-dependent endocytosis was not an option for Curcin. The low-density lipoprotein receptor-related protein 1 (LRP1) was found to mediate clathrin-dependent endocytosis of Curcin C. After LRP1 silencing, there was no significant difference in the 50% inhibitory concentration (IC50) and endocytosis efficiency between Curcin and Curcin C on U2OS cells. These results indicate that LRP1-mediated endocytosis is specific to Curcin C, thus leading to higher U2OS endocytosis efficiency and cytotoxicity than Curcin. [ABSTRACT FROM AUTHOR]

Objectives. Guizhi Fuling Formulation (GZFL), a traditional Chinese medical formulation, consists of Cinnamomi Ramulus, Paeoniae Radix Alba (or Paeoniae Radix Rubra), Moutan Cortex, Persicae Semen, and Poria, with multiple therapeutic functions such as sedation, antitumor activity, anti-inflammation, and neuroprotection. However, its clinical applications remain relatively fragmented, and the underlying mechanisms of GZFL in different diseases are still not very certain. Further research and summary in both application and mechanisms remain to be needed for human health and the best use of GZFL. Therefore, we summarized the multiple pharmacologic effects and possible mechanisms of action of GZFL according to recent 17 years of research. Methods. We retrieved four English and two Chinese databases using these keywords (the formulation name or its synonyms) and searched articles written in English from January 2006 up to February 2022. Key Findings. GZFL exhibits multiple pharmacologic advantages in gynecologic diseases and other expanding diseases such as cancer, blood, and vascular disease, renal failure, inflammation, and brain injury. Possibly due to its diverse bioactive components and pharmacologic activities, GZFL could target the multiple signaling pathways involved in regulating blood circulation, inflammatory and immune factors, proliferation, apoptosis, and so on. Conclusion. This review suggests that GZFL displays promising therapeutic effects for many kinds of diseases, which have been beyond the scope of the original prescription for gynecologic diseases. In this way, we wish to provide a reference and recommendation for further preclinic and clinic studies. [ABSTRACT FROM AUTHOR]

Purpose: To explore the function and regulatory mechanism of IFITM3 in mouse neural retinal progenitor cells (mNRPCs), which was found to be very important not only in the development of the retina in embryos but also in NRPCs after birth. Methods: Published single-cell sequencing data were used to analyze IFITM3 expression in mNRPCs. RNA interference was used to knock down the expression of IFITM3. CCK-8 assays were used to analyze cell viability. RNA-seq was used to assess mRNA expression, as confirmed by real-time quantitative PCR, and immunofluorescence assays and western blots were used to validate the levels of relative proteins, and autophagy flux assay. Lysosomal trackers were used to track the organelle changes. Results: The results of single-cell sequencing data showed that IFITM3 is highly expressed in the embryo, and after birth, RNA-seq showed high IFITM3 expression in mNRPCs. Proliferation and cell viability were greatly reduced after IFITM3 was knocked down. The cell membrane system and lysosomes were dramatically changed, and lysosomes were activated and evidently agglomerated in RAMP-treated cells. The expression of LAMP1 was significantly increased with lysosome agglomeration after treatment with rapamycin (RAMP). Further detection showed that SQSTM1/P62, HSC70 and LAMP-2A were upregulated, while no significant difference in LC3A/B expression was observed; no autophagic flux was generated. Conclusion: IFITM3 regulates mNRPC viability and proliferation mainly through chaperone-mediated autophagy (CMA) but not macroautophagy (MA). IFITM3 plays a significant role in maintaining the homeostasis of progenitor cell self-renewal by sustaining low-level activation of CMA to eliminate deleterious factors in cells. [ABSTRACT FROM AUTHOR]