Peritoneal Metastatic Cancer Stem Cells of Gastric Cancer with Partial Mesenchymal-Epithelial Transition and Enhanced Invasiveness in an Intraperitoneal Transplantation Model

Cancer Stem Cell markers: Symphonic masters of chemoresistance and immune evasion

Cancer Stem Cells (CSCs) are highly tumorigenic, chemoresistant, and immune evasive. They emerge as a central driver that gives rise to the bulk of tumoral mass, modifies the tumor microenvironment (TME), and exploits it, leading to poor clinical outcomes for patients with cancer. The existence of CSCs thus accounts for the failure of conventional therapies and immune surveillance. Identifying CSCs in solid tumors remains a significant challenge in modern oncology, with the use of cell surface markers being the primary strategy for studying, isolating, and enriching these cells. In this review, we explore CSC markers, focusing on the underlying signaling pathways that drive CSC self-renewal, which simultaneously makes them intrinsically chemoresistant and immune system evaders. We comprehensively discuss the autonomous and non-autonomous functions of CSCs, with particular emphasis on their interactions with the tumor microenvironment, especially immune cells. This reciprocal network enhances CSCs malignancy while compromising the surrounding niche, ultimately defining therapeutic vulnerabilities associated with each CSC marker. The most common CSCs surface markers addressed in this review-CD44, CD133, ICAM1/CD54, and LGR5-provide insights into the interplay between chemoresistance and immune evasion, two critically important phenomena in disease eradication. This new perspective on the state-of-the-art of CSCs will undoubtedly open new avenues for therapy.

TTN-AS1 delivered by gastric cancer cell-derived exosome induces gastric cancer progression through in vivo and in vitro studies

Extracellular communication within the tumor microenvironment exerts critical functions in tumor progression. Moreover, exosomes are capable of packaging into long non-coding RNAs (lncRNAs) to regulate extracellular communication. We tried to discuss the role of exosomal lncRNA TTN-AS1 and its molecular mechanism on gastric cancer (GC) progression. Bioinformatics analysis depicted increased TTN-AS1 in GC which shared correlation with poor prognosis. Clinical tissue and cellular experiments also confirmed the elevation of TTN-AS1 in GC tissues and cells. GC cell (AGS)-derived Exo could be uptake by NCI-N87 cells to induce malignant features of GC cells. Functionally, TTN-AS1 could upregulate ZEB1 expression by binding to miR-499a-5p. In addition, in vitro experiments demonstrated that ZEB1 targeted and activated CDX2 transcription and promoted CDX2 expression; silencing CDX2 inhibited malignant phenotypes of AGS and NCI-N87 cells. Furthermore, Exo-TTN-AS1 promoted GC cell growth and migration by promoting CDX2 expression. Exosomal TTN-AS1 from GC cells could also promote metastasis of GC in vivo. In conclusion, our findings provided evidence describing that exosomes derived from GC cells transferred TTN-AS1 to GC cells, which aggravate GC through the miR-499a-5p/ZEB1/CDX2 axis. 1. Exo derived from GC cells promotes the growth and metastasis of GC cells by carrying TTN-AS1. 2. TTN-AS1 acts as a ceRNA to adsorb miR-499a-5p to regulate the expression of ZEB1. 3. ZEB1 targets and activates CDX2 transcription. 4. GC cell-derived Exo-TTN-AS1 enhances the growth and metastasis of GC cell xenografts in vivo.

Integration of Genomic Biology Into Therapeutic Strategies of Gastric Cancer Peritoneal Metastasis

The peritoneum is a common site of metastasis in advanced gastric cancer (GC). Diagnostic laparoscopy is now routinely performed as part of disease staging, leading to an earlier diagnosis of synchronous peritoneal metastasis (PM). The biology of GCPM is unique and aggressive, leading to a dismal prognosis. These tumors tend to be resistant to traditional systemic therapy, and yet, this remains the current standard-of-care recommended by most international clinical guidelines. As this is an area of unmet clinical need, several translational studies and clinical trials have focused on addressing this specific disease state. Advances in genomic sequencing and molecular profiling have revealed several promising therapeutic targets and elucidated novel biology, particularly on the role of the surrounding tumor microenvironment in GCPM. Peritoneal-specific clinical trials are being designed with a combination of locoregional therapeutic strategies with systemic therapy. In this review, we summarize the new knowledge of cancer biology, advances in surgical techniques, and emergence of novel therapies as an integrated strategy emerges to address GCPM as a distinct clinical entity.

Overexpression of ring finger protein 20 inhibits the progression of liver fibrosis via mediation of histone H2B lysine 120 ubiquitination

Liver fibrosis is a chronic liver injury that leads to liver cirrhosis and liver cancer. Ring finger protein 20 (RNF20), also named as E3 ubiquitin-protein ligase BRE1A, has been reported to be involved in chronic liver diseases. However, the role of RNF20 in liver fibrosis remains unclear. To mimic liver fibrosis in vitro, LX-2 cells were treated with TGF-β. Gene and protein expressions were detected by RT-qPCR and western blot, respectively. The mechanism by which RNF20 mediated the progression of liver fibrosis was explored by bioinformatics analysis. Finally, in vivo mouse model of liver fibrosis was established to detect the function of RNF20. The results indicated that TGF-β-induced increase of cell viability and migration was significantly reversed by RNF20 overexpression. Consistently, overexpression of RNF20 significantly reversed TGF-β-induced activation of fibrotic proteins in LX-2 cells. Meanwhile, VEGFA, TNF-α and IL-6 were found to be the downstream targets of RNF20 in LX-2 cells. Moreover, RNF20 overexpression notably inhibited the progression of liver fibrosis via ubiquitination of H2B. Finally, RNF20 upregulation significantly attenuated the symptom of liver fibrosis in vivo. In summary, overexpression of RNF20 significantly inhibited the progression of liver fibrosis in vitro and in vivo. Therefore, RNF20 might serve as a new target for the treatment of liver fibrosis.