Background
Transmembrane 4 L six family member 1 (TM4SF1) is upregulated in several epithelial cancers and is closely associated with poor prognosis. However, the role of TM4SF1 and its potential mechanism in colorectal cancer (CRC) remain elusive.
Methods
We investigated the expression of TM4SF1 in the Oncomine, the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases and confirmed the results by immunohistochemistry (IHC), qPCR and Western blotting (WB) of CRC tissues. The effect of TM4SF1 on the epithelial-to-mesenchymal transition (EMT) and cancer stemness of CRC cells was investigated by Transwell, wound healing and sphere formation assays. A series of in vitro and in vivo experiments were conducted to reveal the mechanisms by which TM4SF1 modulates EMT and cancer stemness in CRC.
Results
TM4SF1 expression was markedly higher in CRC tissues than in non-tumour tissues and was positively correlated with poor prognosis. Downregulation of TM4SF1 inhibited the migration, invasion and tumour sphere formation of SW480 and LoVo cells. Conversely, TM4SF1 overexpression significantly enhanced the migration, invasion and tumoursphere formation potential of CRC cells, Additionally, TM4SF1 silencing inhibited the EMT mediated by transforming growth factor-β1 (TGF-β1). Mechanistically, gene set enrichment analysis (GSEA) predicted that the Wnt signalling pathway was one of the most impaired pathways in TM4SF1-deficient CRC cells compared to controls. The results were further validated by WB, which revealed that TM4SF1 modulated SOX2 expression in a Wnt/β-catenin activation-dependent manner. Furthermore, we found that knockdown of TM4SF1 suppressed the expression of c-Myc, leading to decreased c-Myc binding to the SOX2 gene promoter. Finally, depletion of TM4SF1 inhibited metastasis and tumour growth in a xenograft mouse model.
Conclusion
Our study substantiates a novel mechanism by which TM4SF1 maintains cancer cell stemness and EMT via the Wnt/β-catenin/c-Myc/SOX2 axis during the recurrence and metastasis of CRC.
Gastric cancer (GC) is a leading cause of cancer-related death with poor prognosis. Growing evidence has shown that long noncoding ribonucleic acid (lncRNA) FEZ family zinc finger 1 antisense RNA 1(FEZF1-AS1), an “oncogene,” regulates tumor progression and supports cancer stem cell. However, the tumorigenic mechanism of FEZF1-AS1 on gastric cancer stem cell (GCSC) is yet to be investigated. Here, we discovered that FEZF1-AS1 was upregulated in GC tissues and cell lines. Knockdown of FEZF1-AS1 inhibited sphere formation and decreased expression of stem factors and markers. Moreover, FEZF1-AS1 silence also suppressed cell proliferation, viability, invasion, and migration of GCSCs. MiR-363-3p is used as a target of FEZF1-AS1, because its expression was suppressed by FEZF1-AS1 in GCSCs. FEZF1-AS1 could sponge miR-363-3p and increased the expression of high-mobility group AT-hook 2 (HMGA2). The expression of FEZF1-AS1 and miR-363-3p, as well as that of miR-363-3p and HMGA2, was negatively correlated in GC tissues. Finally, FEZF1-AS1 contributed to promotion of GCSCs progression partially through inhibition of miR-363-3p. Subcutaneous xenotransplanted tumor model revealed that silence of FEZF1-AS1 suppressed in vivo tumorigenic ability of GSCS via downregulation of HMGA2. In general, our findings clarified the critical regulatory role of FEZF1-AS1/miR-363-3p/HMGA2 axis in GCSC progression, providing a potential therapeutic target for GC.
Rationale:This article is aimed to retrospect the clinicopathological data of 2 cases of gastric MANENCs. MANEC is a rare biphasic tumor type that is coexistence of dual neuroendocrine and adenocarcinoma differentiation with each composing exceeding 30% volume. Gastric MANEC have just been reported anecdotally in the literature due to their rarity and heterogeneity. According to our study, these neoplasms have 3 different metastasis patterns: only adenocarcinomatous or neuroendocrine carcinoma and both of the 2 components. We first focus on the correlation of metastasis characteristics with prognosis in gastric MANEC, which may be potential implications for the choice of chemotherapy.Patient concerns:The 2 cases of patient shared several symptoms: epigastric discomfort, weight loss, hematemesis, or melena.Diagnosis:The 2 patients were diagnosis as MANEC based on the identification of histopathological analysis. In case 1, the poor differentiated adenocarcinoma accounted for 30%, the neuroendocrine part account for 70% and both of the 2 components metastasized to the lymph nodes, whereas in case 2, poorly differentiated adenocarcinoma accounted for 70%, the neuroendocrine part for 30% and only the glandular component invaded regional lymph nodes.Interventions:The first patient underwent laparoscopic radical gastrectomy and underwent adjuvant chemotherapy, combination of cisplatin, and etoposide successfully. The second patient received radical gastronomy, and did not receive any chemotherapy due to general weakness.Outcomes:The first patient is alive with no evidence of recurrence, and the second patient died 6 months after the operation.Lessons:The assessment of metastatic sites should be a routine pathological practice, which is crucial for clinical decision-making and the selection of management.
The 2019 Coronavirus Disease (COVID-19) has become an unprecedented public crisis. We retrospectively investigated the clinical data of 197 COVID-19 patients and identified 88 patients as disease aggravation cases. Compared with patients without disease aggravation, the aggravation cases had more comorbidities, including hypertension (25.9%) and diabetes (20.8%), and presented with dyspnoea (23.4%), neutrophilia (31.5%), and lymphocytopenia (46.7%). These patients were more prone to develop organ damage in liver, kidney, and heart (P < 0.05). A multivariable regression analysis showed that advanced age, comorbidities, dyspnea, lymphopenia, and elevated levels of Fbg, CTnI, IL-6, and serum ferritin were significant predictors of disease aggravation. Further, we performed a Kaplan–Meier analysis to evaluate the prognosis of COVID-19 patients, which suggested that 64.9% of the patients had not experienced ICU transfers and survival from the hospital.
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