Human umbilical cord mesenchymal stem cells promote carcinoma growth and lymph node metastasis when co-injected with esophageal carcinoma cells in nude mice.

BACKGROUND: Human umbilical cord blood derived-mesenchymal stem cells (hUCMSCs) offer an attractive alternative to bone marrow-derived MSCs (BMMSCs) for cell-based therapy as it is a less invasive source of biological material. However, limited studies have been conducted with hUCMSCs as compared to BMMSCs. The present study was conducted to evaluate the effects of hUCMSCs in esophageal carcinoma (EC). METHODS: hUCMSCs together with EC cells were transplanted subcutaneously into BALB/c nude mice to observe the effects of hUCMSCs on tumor establishment. hUCMSCs injected through the caudal vein to the mice with pre-established EC to observe the effects of hUCMSCs on tumor outgrowth. In order to elucidate the underlying mechanisms, we also performed in vitro experiments including directly co-culture, transwell assay, proliferation assay and western blotting analysis. RESULTS: hUCMSCs promoted EC formation in nude mice. In the in vivo model of pre-established EC, intravenously injected hUCMSCs potently promoted tumor growth. When in vitro co-cultured with hUCMSCs, EC cells proliferation increased. After co-cultured with hUCMSCs through transwell system, EC cells showed increased proliferation. Through transwell assay, we also observed that EC cells recruited MSCs, and MSCs promoted EC cells migration and invasion. Western blotting data showed that the expressions of proliferation related proteins Bcl-2, survivin and metastasis related proteins MMP-2 and MMP-9 were up-regulated in the EC cells transwell co-cultured with hUCMSCs. CONCLUSIONS: Our results indicated that hUCMSCs could favor tumor growth in vivo and in vitro. Thus, the exploitation of hUCMSCs in new therapeutic strategies should be cautious under the malignant conditions.

A Novel Mis-Seg-Focus Loss Function Based on a Two-Stage nnU-Net Framework for Accurate Brain Tissue Segmentation.

Brain tissue segmentation plays a critical role in the diagnosis, treatment, and study of brain diseases. Accurately identifying these boundaries is essential for improving segmentation accuracy. However, distinguishing boundaries between different brain tissues can be challenging, as they often overlap. Existing deep learning methods primarily calculate the overall segmentation results without adequately addressing local regions, leading to error propagation and mis-segmentation along boundaries. In this study, we propose a novel mis-segmentation-focused loss function based on a two-stage nnU-Net framework. Our approach aims to enhance the model's ability to handle ambiguous boundaries and overlapping anatomical structures, thereby achieving more accurate brain tissue segmentation results. Specifically, the first stage targets the identification of mis-segmentation regions using a global loss function, while the second stage involves defining a mis-segmentation loss function to adaptively adjust the model, thus improving its capability to handle ambiguous boundaries and overlapping anatomical structures. Experimental evaluations on two datasets demonstrate that our proposed method outperforms existing approaches both quantitatively and qualitatively.

Pancreatic adverse events of immune checkpoint inhibitors therapy for solid cancer patients: a systematic review and meta-analysis.

Objective: This review aims to determine the incidence and risk of pancreatic adverse events (AEs) associated with immune checkpoint inhibitors (ICIs) therapy for solid tumors. Methods: We conducted a comprehensive systematic literature search in PubMed, Embase, and Cochrane Library up to March 15, 2023, to identify all randomized controlled trials comparing ICIs with standard treatment in solid tumors. We included studies that reported immune-related pancreatitis or elevation of serum amylase or lipase levels. Following protocol registration in PROSPERO, we conducted a systematic review and meta-analysis. Results: 59 unique randomized controlled trials with at least one ICI-containing arm (41 757 patients) were retrieved. The incidences for all-grade pancreatitis, amylase elevation and lipase elevation were 0.93% (95% CI 0.77-1.13), 2.57% (95% CI 1.83-3.60) and 2.78% (95% CI 1.83-4.19), respectively. The incidences for grade ≥3 pancreatitis, amylase elevation and lipase elevation were 0.68% (95% CI 0.54-0.85), 1.17% (95% CI 0.83-1.64) and 1.71% (95% CI 1.18-2.49), respectively. The use of ICIs was associated with an increased risk of all-grade pancreatic immune-related AEs (irAEs) including pancreatitis (OR=2.04, 95% CI 1.42-2.94, P =0.0001), amylase elevation (OR=1.91, 95% CI 1.47-2.49, P < 0.0001) and lipase elevation (OR=1.77, 95% CI 1.37-2.29, P < 0.0001). In addition to these, the post-hoc analysis found that PD-1 inhibitors had a significant higher risk of pancreatic AEs compared with PD-L1 inhibitors and the patients undergoing dual ICI therapy were at a significantly higher risk of pancreatic AEs than the patients receiving single ICI therapy. Conclusion: Our study provides an overview of the incidence and risk of ICI-associated pancreatitis and pancreatic enzyme elevations in the treatment of solid tumors. Our findings may help raise awareness among clinicians of the potential for ICI-associated pancreatic AEs in clinical practice. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO, identifier 345350.

TP53 Co-Mutations in Advanced EGFR-Mutated Non-Small Cell Lung Cancer: Prognosis and Therapeutic Strategy for Cancer Therapy.

Lung cancer is the leading cause of cancer-related deaths worldwide. As the most prevalent molecular mutation subtypes in non-small cell lung cancer (NSCLC), EGFR-TKIs are currently a standard first-line therapy for targeting the mutated EGFR in advanced NSCLC patients. However, 20-30% of this subset of patients shows primary resistance to EGFR-TKIs. Patients with co-mutations of EGFR and several other genes have a poor response to EGFR-TKIs, whereas the prognostic and predictive significance of EGFR/TP53 co-mutation in NSCLC patients remains controversial. Meanwhile, little is known about how to choose an optimal therapeutic strategy for this subset of patients. Presently, no drugs targeting TP53 mutations are available on the market, and some p53 protein activators are in the early stage of clinical trials. A combination of EGFR-TKIs with antiangiogenic agents or chemotherapy or other agents might be a more appropriate strategy to tackle the problem. In this review, we describe the prognostic and predictive value of EGFR/TP53 co-mutation in NSCLC patients, investigate the mechanisms of this co-mutation affecting the response to EGFR-TKIs, and further explore optimal regimens effectively to prolong the survival time of the NSCLC patients harboring this co-mutation.

Cardiovascular Toxicity With PD-1/PD-L1 Inhibitors in Cancer Patients: A Systematic Review and Meta-Analysis.

Background: PD-1/PD-L1 inhibitors have significantly improved the outcomes of those patients with various malignancies. However, the incidence of adverse events also increased. This meta-analysis aims to systematically evaluate the risk of cardiovascular toxicity in patients treated with PD-1/PD-L1 inhibitors. Materials and methods: We searched PubMed, Embase, the Cochrane Library databases for all randomized controlled trials (RCTs) comparing all-grade and grade 3-5 cardiovascular toxicity of single-agent PD-1/PD-L1 inhibitors to placebo/chemotherapy, PD-1/PD-L1 inhibitors combined with chemotherapy to chemotherapy, or PD-1/PD-L1 inhibitors combined with CTLA-4 inhibitors to single-agent immune checkpoint inhibitors (ICIs) and pooled our data in a meta-analysis stratified by tumor types and PD-1 or PD-L1 inhibitors. The Mantel-Haenszel method calculated the odds ratio (OR) and its corresponding 95% confidence intervals (CIs). Results: A total of 50 trials were included in the analysis. Single-agent PD-1/PD-L1 inhibitors increased the risk of all-grade cardiotoxicity compared with placebo (OR=2.11, 95%CI 1.02-4.36, P=0.04). Compared with chemotherapy, patients receiving PD-1/PD-L1 inhibitors combined with chemotherapy had a significant higher risk of all-grade (OR=1.53, 95%CI 1.18-1.99, P=0.001) and grade 3-5 cardiotoxicity (OR=1.63, 95%CI 1.11-2.39, P=0.01) cardiotoxicity, especially patients with non-small cell lung cancer (NSCLC) [all-grade cardiotoxicity (OR=1.97, 95%CI 1.14-3.41, P=0.02) and grade 3-5 cardiotoxicity (OR=2.15, 95%CI 1.08-4.27, P=0.03)]. Subgroup analysis showed that PD-1 inhibitors combined with chemotherapy were associated with a higher risk of grade 3-5 cardiotoxicity (OR=2.08, 95%CI 1.18-3.66, P=0.01). Compared with placebo or chemotherapy, single-agent PD-1/PD-L1 inhibitors did not increase the risk of all-grade of myocarditis, arrhythmia and hypertension. However, PD-1/PD-L1 inhibitors combined with chemotherapy increased the risk of all-grade arrhythmia (OR=1.63, 95%CI 1.07-2.46, P=0.02) [PD-L1 inhibitor-containing treatment (OR=1.75, 95%CI 1.09-2.80, P=0.02)], and the risk of all-grade hypertension (OR=1.34, 95%CI 1.02-1.77, P=0.04) and grade 3-5 hypertension (OR=1.54, 95%CI 1.10-2.15, P=0.01). Conclusions: Our results suggest that single-agent PD-1/PD-L1 inhibitors increase the risk of all-grade cardiotoxicity, PD-1/PD-L1 inhibitors combined with chemotherapy increase the risk of all-grade and grade 3-5 cardiotoxicity, especially in those patients treated with PD-1 inhibitor-containing treatment and those with NSCLC. In addition, PD-1/PD-L1 inhibitors combined with chemotherapy increase the risk of arrhythmia and hypertension. Therefore, this evidence should be considered when assessing the benefits and risks of PD-1/PD-L1 inhibitors in treating malignancies. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022303115.

RhoA regulates G1-S progression of gastric cancer cells by modulation of multiple INK4 family tumor suppressors.

RhoA, a member of the Rho GTPase family, has been extensively studied in the regulation of cytoskeletal dynamics, gene transcription, cell cycle progression, and cell transformation. Overexpression of RhoA is found in many malignancies and elevated RhoA activity is associated with proliferation phenotypes of cancer cells. We reported previously that RhoA was hyperactivated in gastric cancer tissues and suppression of RhoA activity could partially reverse the proliferation phenotype of gastric cancer cells, but the underlying mechanism has yet to be elucidated. It has been reported that RhoA activation is crucial for the cell cycle G(1)-S procession through the regulation of Cip/Kip family tumor suppressors in benign cell lines. In this study, we found that selective suppression of RhoA or its effectors mammalian Diaphanous 1 and Rho kinase (ROCK) by small interfering RNA and a pharmacologic inhibitor effectively inhibited proliferation and cell cycle G(1)-S transition in gastric cancer lines. Down-regulation of RhoA-mammalian Diaphanous 1 pathway, but not RhoA-ROCK pathway, caused an increase in the expression of p21(Waf1/Cip1) and p27(Kip1), which are coupled with reduced expression and activity of CDK2 and a cytoplasmic mislocalization of p27(Kip1). Suppression of RhoA-ROCK pathway, on the other hand, resulted in an accumulation of p15(INK4b), p16(INK4a), p18(INK4c), and p19(INK4d), leading to reduced expression and activities of CDK4 and CDK6. Thus, RhoA may use two distinct effector pathways in regulating the G(1)-S progression of gastric cancer cells.

[Analysis of the P53 transcriptional activity in gastric cancer].

OBJECTIVE: To investigate the transcriptional activity of P53 in gastric cancer. METHODS: The activity of p53 in gastric cancer was investigated by dual-luciferase reporter assay. The coding sequence of the p53 was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and sequenced. The expression of P21WAF1/Cip1, Gadd45alpha and Mdm2 was detected by immunohistochemistry in 76 samples of gastric carcinoma, and their adjacent tissues were analyzed as control. RESULTS: The p53 activity was higher in human normal cell lines than that of gastric cancer. Furthermore, the transcriptional activity of P53 was lowest in MKN28 cells in which p53 was mutated. The expression level of P21WAF1/Cip1, Gadd45alpha and Mdm2 in the adjacent tissues was higher than that of cancer tissues (P<0.05), and there was a tendency of decline in the positive ratio with the poor differentiation of the carcinoma (P<0.05). In addition, a strong linear correlation was observed between P21WAF1/Cip1, Gadd45alpha and Mdm2 (P<0.05). CONCLUSION: Changes of P53 transcriptional activity play an important role in the development of gastric cancer. p53 mutation could affect its transcriptional activity. P21WAF1/Cip1, Gadd45alpha and Mdm2 are a group of effecters that could reflect P53 transcriptional activity when detected together in cancer tissues.

[Cultivation and characterization of tumor spheres generated from human colorectal cancer cell lines].

OBJECTIVE: To study on the cultivation method for tumor spheres from colorectal cancer cell lines and identify whether resulting Colo205 spheroid cells display cancer stem cell characteristics. METHODS: Lovo, Colo205 and SW480 cells were seeded in serum free medium (SFM) with EGF and bFGF. Flow cytometry analysis, cell invasion assay and xenograft experiment were applied to examine the cell surface marker expression pattern, cell invasive ability and in vivo tumorigenicity of both Colo205 spheres and parental cells. CD44 expression of tumor spheroid cells was also analyzed after cultured with serum supplemented medium by flow cytometry. CD44, Musashi-1 and Oct4 mRNA were detected in these two cells by RT-PCR. RESULTS: Tumor spheres could be generated from three colorectal cancer cell lines in SFM. The formation and proliferation of tumor spheres were benefited from fresh SFM, cell dissociation reagent Accutase and the floating status of cancer cells. The overwhelming majority of spheroid cells were CD44+ cells. But CD44+ cells were gradually decreased when spheres cultured with serum supplemented medium. Colo205 spheres have higher Musashi-1 and Oct4 mRNA expression, tumor-initiating capability and invasive ability compared with those of parental cells. CONCLUSION: Tumor spheres in which enrich cancer stem cells can be generated and matained from colorectal cancer cell lines in SFM on floating-culture condition.

[The effect of Rac1 siRNA on the biological behaviors of gastrointestinal cancer cells].

OBJECTIVE: To explore the effect of Rac1 siRNA on the expression of Rac1 and the biological behaviors of gastrointestinal cancer cells. METHODS: Rac1 siRNA was transfected into human gastric cancer cell line SGC803 and colorectal cancer cell line Lovo by lipofectamine 2000. The expression of Rac1 in these cell lines were detected by Western blot and RT-PCR after 48 hours of the transfection. The effect of Rac1 on the proliferation of human gastric cancer cell line SGC803 and colorectal cancer cell line Lovo were tested by CCK8 kit. The motility of the transfected and the control cancer cells were assessed by Wound-healing assay and invasion assay. The apoptotic index was evaluated by Hoechst 33258 staining and FCM. RESULTS: Rac1 siRNA can down-regulated the expression of Rac1 on human gastric cancer cell line SGC803 and colorectal cancer cell line Lovo remarkably, and Rac1 siRNA can inhibit both the proliferation and motility of the transfectants. Analysis of apoptosis demonstrated that Rac1 siRNA can promote apoptosis of the gastric cancer cells and colorectal cancer cells. CONCLUSION: Rac1 play an important role in the regulation of biological behaviors of human gastric cancer and colorectal cancer cells, and the interference of Rac1 expression could provide a novel path in reversing the malignant phenotypes of these malignancies.

The Rho GTPase RhoE is a p53-regulated candidate tumor suppressor in cancer cells.

Previous studies have shown that RhoE, an atypical member of the Rho GTPase family, may play an opposite role to RhoA in regulating cell proliferation and invasion. To explore the relationship between RhoE and the malignant phenotypes of human cancer, we have determined the expression patterns of RhoE in varying grade of human cancer tissues and tested the effects of RhoE expression in several RhoE underexpressing cancer cell lines. Systemic immunocytochemistry analyses of gastric, colorectal, lung and breast carcinomas, respectively, showed that RhoE protein expression was significantly decreased in most cancer cases compared with that of adjacent normal tissues. Enhanced RhoE expression could markedly inhibit proliferation, migration and invasion and induce apoptosis of the cancer cells which have relatively low levels of endogenous RhoE expression. Wild-type p53 (wt-p53) could strongly increase RhoE expression in p53-transfected cells. Furthermore, the luciferase assays indicated that wt-p53 significantly enhanced the activities of RhoE promoter compared with mutant p53 (mt-p53) in PC3 cells (p53 null). Collectively, data are presented showing that RhoE may participate in human cancer progression and act as a candidate target of p53, and these findings also strongly suggest that RhoE may be a new candidate tumor suppressor and could serve as a potential target in the gene therapy of cancer.

miR-185 targets RhoA and Cdc42 expression and inhibits the proliferation potential of human colorectal cells.

Increasing evidence in the past few years has shown that miRNAs could serve functionally as "oncogenes" or "tumor suppressor genes" and regulate multiple cellular processes relevant to carcinogenesis and cancer progression. Both RhoA and Cdc42, two members of the Rho GTPase family, are found to be upregulated in several types of human tumors including colorectal cancer, and have been implicated in cancer initiation and progression. In the present studies, we found that miR-185 expression greatly inhibited the proliferation potential of Hela cells. An examination of the predicted targets of miR-185 revealed RhoA and Cdc42 among the putative targets that are crucial for cell proliferation. A genomic sequence analysis indicated that nt 1844-1852 of the RhoA 3'UTR and nt 1382-1396 of the cdc42 3'UTR encode for miR-185 target matching sequences and they are highly conserved across different species. Using a luciferase-reporter assay, we show that miR-185 expression significantly suppressed the RhoA and Cdc42 3'UTR activities, and the inhibitory effect was lost when the putative target sites for miR-185 were mutated. Consistent with these results, ectopic expression of miR-185 reduced protein levels of RhoA and Cdc42 in cells, indicating miR-185 functionally regulates RhoA and Cdc42 abundance. Similar to the effects of knocking down RhoA and/or Cdc42 expression, miR-185 effectively inhibited proliferation, induced G1 cell cycle arrest and apoptosis, and blocked invasion of colorectal cancer cells. Thus, miR-185 is a negative regulator of RhoA and Cdc42 and their cellular activities, and could inhibit proliferation and invasion of colorectal cancer cells.

[Expression of RhoE in lung and breast cancer and its clinical significance.].

BACKGROUND: Rho family is closely related with the growth , differentiation and metastasis of tumer cells. The objective of this work is to investigate the expression of RhoE in lung and breast carcinoma and their corresponding adjacent tissues, as well as its relationship between the expression and clinical pathological grades. The results of this study provide evidences for exploring the biological functions and clinical significance of RhoE. METHODS: The expression of RhoE was detected by immunohistochemistry in 62 lung carcinoma samples and 34 breast carcinoma samples, and their corresponding adjacent tissues were taken as control. RESULTS: RhoE was generally expressed in normal tissues, but the expression level of RhoE in carcerous tissues was decreased or absent. The stained value of breast carcinoma was 3.65+/-0.62, but the adjacent cancerous tissues was 10.53+/-0.44, significantly higher than that of the adjacent cancerous tissues (t=12.402, P<0.001). While the stained value of lung carcinoma was 2.19+/-0.19, lower than that of the adjacent cancerous tissues (4.11+/-0.24, t =7.123, P<0.005). Moreover, there is a declining tendency of the stained value as the poor differentiation of the carcinoma (Chi-Square=26.536, P<0.005). CONCLUSIONS: The expression of RhoE in carcerous tissues was remarkbaly decreased. Considering the recent research achievement and our early experimental results about RhoE, we inferred that RhoE may play a negative role in the development and progression of lung and breast carcinoma. So further research on RhoE would provide a new target for the molecular targeting therapy of cancer.