Robotic natural orifice specimen extraction surgery versus robotic transabdominal specimen extraction surgery for early-stage rectal cancer: a multicenter propensity score-matched analysis (in China).

BACKGROUND: Despite the global increase in the adoption of robotic natural orifice specimen extraction surgery (R-NOSES), its advantages over robotic transabdominal specimen extraction surgery (R-TSES) for treating early-stage rectal cancer remain debated. There is scant nationwide, multicenter studies comparing the surgical quality and short-term outcomes between R-NOSES and R-TSES for this condition. OBJECTIVE: This retrospective cohort study was conducted nationally across multiple centers to compare the surgical quality and short-term outcomes between R-NOSES and R-TSES in early-stage rectal cancer. DESIGN: Multicenter retrospective cohort trial. SETTING: Eight experienced surgeons from 8 high-volume Chinese colorectal cancer treatment centers. PATIENTS: The study included 1086 patients who underwent R-NOSES or R-TSES from October 2015 to November 2023 at the 8 centers. Inclusion criteria were: (1) histologically confirmed rectal adenocarcinoma; (2) robotic total mesorectal excision; (3) postoperative pathological staging of TisN0M0 or T1-2N0M0; (4) availability of complete surgical and postoperative follow-up data. Patients were matched 1:1 in the R-NOSES and R-TSES groups using the propensity score matching (PSM) technique. RESULTS: After PSM, 318 matched pairs with well-balanced patient characteristics were identified. The operation time for the R-NOSES group was significantly longer than that for the R-TSES group [140 min (125-170 min) vs. 140 min (120-160 min), P = 0.032]. Conversely, the times to first flatus and initial oral intake in the R-NOSES group were significantly shorter than those in the R-TSES group [48 h (41-56 h) vs. 48 h (44-62 h), P = 0.049 and 77 h (72-94 h) vs. 82 h (72-96 h), P = 0.008], respectively. Additionally, the length of postoperative hospital stay was shorter in the R-NOSES group compared with the R-TSES group [7 day (7-9 day) vs. 8 day (7-9 day), P = 0.005]. The overall postoperative complication rates were similar between the groups (10.7% in the R-NOSES group vs. 11.9% in the R-TSES group, P = 0.617). However, the R-NOSES group had a lower incidence of wound complications compared to the R-TSES group (0.0% vs. 2.2%, P = 0.015). Regarding surgical stress response, the R-NOSES group showed superior outcomes. Additionally, patients in the R-NOSES group required fewer additional analgesics on postoperative days 1, 3, and 5 and reported lower pain scores compared to the R-TSES group. The body image scale (BIS) and cosmetic scale (CS) scores were also significantly higher in the R-NOSES group. Furthermore, the R-NOSES group demonstrated significantly better outcomes in functional dimensions such as physical, role, emotional, social, and cognitive functioning, and in symptoms like fatigue and pain, when compared to the R-TSES group. LIMITATIONS: It is imperative to ensure the safe and standardized implementation of R-NOSES through the establishment of a uniform training protocol. CONCLUSIONS: These results affirm that R-NOSES is a safe and effective treatment for early-stage rectal cancer when meticulously executed by skilled surgeons.

Roles of tumor-associated macrophages in anti-PD-1/PD-L1 immunotherapy for solid cancers.

In recent years, tumor immunotherapy has made significant progress. However, tumor immunotherapy, particularly immune checkpoint inhibitors (e.g., PD-1/PD-L1 inhibitors), benefits only a tiny proportion of patients in solid cancers. The tumor microenvironment (TME) acts a significant role in tumor immunotherapy. Studies reported that tumor-associated macrophages (TAMs), as one of the main components of TME, seriously affected the therapeutic effect of PD-1/PD-L1 inhibitors. In this review, we analyzed TAMs from epigenetic and single-cell perspectives and introduced the role and mechanisms of TAMs in anti-programmed death protein 1(anti-PD-1) therapy. In addition, we summarized combination regimens that enhance the efficacy of tumor PD-1/PD-L1 inhibitors and elaborated on the role of the TAMs in different solid cancers. Eventually, the clinical value of TAMs by influencing the therapeutic effect of tumor PD-1/PD-L1 inhibitors was discussed. These above are beneficial to elucidate poor therapeutic effect of PD-1/PD-L1 inhibitors in solid tumors from the point of view of TAMs and explore the strategies to improve its objective remission rate of solid cancers.

Effects of RNA methylation on Tumor angiogenesis and cancer progression.

Tumor angiogenesis plays vital roles in the growth and metastasis of cancer. RNA methylation is one of the most common modifications and is widely observed in eukaryotes and prokaryotes. Accumulating studies have revealed that RNA methylation affects the occurrence and development of various tumors. In recent years, RNA methylation has been shown to play an important role in regulating tumor angiogenesis. In this review, we mainly elucidate the mechanisms and functions of RNA methylation on angiogenesis and progression in several cancers. We then shed light on the role of RNA methylation-associated factors and pathways in tumor angiogenesis. Finally, we describe the role of RNA methylation as potential biomarker and novel therapeutic target.

Ultrasound-targeted microbubble destruction remodels tumour microenvironment to improve immunotherapeutic effect.

Cancer immunotherapy (CIT) has gained increasing attention and made promising progress in recent years, especially immune checkpoint inhibitors such as antibodies blocking programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4). However, its therapeutic efficacy is only 10-30% in solid tumours and treatment sensitivity needs to be improved. The complex tissue environment in which cancers originate is known as the tumour microenvironment (TME) and the complicated and dynamic TME is correlated with the efficacy of immunotherapy. Ultrasound-targeted microbubble destruction (UTMD) is an emerging technology that integrates diagnosis and therapy, which has garnered much traction due to non-invasive, targeted drug delivery and gene transfection characteristics. UTMD has also been studied to remodel TME and improve the efficacy of CIT. In this review, we analyse the effects of UTMD on various components of TME, including CD8+ T cells, tumour-infiltrating myeloid cells, regulatory T cells, natural killer cells and tumour vasculature. Moreover, UTMD enhances the permeability of the blood-brain barrier to facilitate drug delivery, thus improving CIT efficacy in vivo animal experiments. Based on this, we highlight the potential of immunotherapy against various cancer species and the clinical application prospects of UTMD.

Effect and mechanism of circRNAs in tumor angiogenesis and clinical application.

Tumor blood vessels provide oxygen and necessary nutrients for the tumor, which provides the basis for tumor metastasis. Therefore, tumor angiogenesis plays a very important role in tumor growth and metastasis. In contrast to linear RNAs, circRNAs represent a type of closed-loop RNA with diverse biological functions. At the same time, circRNAs have strong stability, timeliness, tissue specificity and disease specificity. With the rapid development of next-generation sequencing and bioinformatics, there have been an increasing number of studies on circRNAs. At present, a large number of studies have reported that circRNAs regulate tumor growth, invasion, metastasis, tumor metabolism, tumor immunity and other biological functions. Increasing evidence has shown that circRNAs also play an important role in tumor angiogenesis. In this review, we briefly introduced tumor angiogenesis and circRNAs and outlined the main ways that circRNAs affect tumor angiogenesis from multiple aspects. Finally, we further explored the potential clinical application value of circRNAs in the context of tumor angiogenesis.

Interaction between intestinal microbiota and tumour immunity in the tumour microenvironment.

In recent years, an increasing number of studies have reported that intestinal microbiota have an important effect on tumour immunity by affecting the tumour microenvironment (TME). The intestinal microbiota are closely associated with various immune cells, such as T lymphocytes, natural killer cells (NK cells) and macrophages. Some bacteria, such as Akkermansia muciniphila (A. muciniphila) and Lactobacillus reuteri (L. reuteri), have been shown to improve the effect of tumour immunity. Furthermore, microbial imbalance, such as the increased abundance of Fusobacterium nucleatum (F. nucleatum) and Helicobacter hepaticus (H. hepaticus), generally causes tumour formation and progression. In addition, some microbiota also play important roles in tumour immunotherapy, especially PD-L1-related therapies. Therefore, what is the relationship between these processes and how do they affect each other? In this review, we summarize the interactions and corresponding mechanisms among the intestinal microbiota, immune system and TME to facilitate the research and development of new targeted drugs and provide new approaches to tumour therapy.

Robotic colorectal cancer surgery in China: a nationwide retrospective observational study.

BACKGROUND: Robotic colorectal cancer surgery is widely accepted and applied. However, there is still no objective and comprehensive assessment on the data of nationwide multicenter series. METHOD: A total of 28 medical centers in Mainland China participated in this nationwide retrospective observational study. From the first case performed in each center to the last until December 2017, patients with robotic resection for primary tumor and pathologically confirmed colorectal adenocarcinoma were consecutively enrolled. Clinical, pathological and follow-up data were collected and analyzed. RESULTS: A total of 5389 eligible patients were finally enrolled in this study, composing 72.2% of the total robotic colorectal surgery volume of Mainland China in the same period. For resections of one bowel segment of primary tumor, the postoperative mortality rate was 0.08% (4/5063 cases), and the postoperative complication rate (Clavien-Dindo grade II or higher) was 8.6% (434/5063 cases). For multiple resections, the postoperative mortality rate was 0.6% (2/326 cases), and the postoperative complication rate was 16.3% (53/326 cases). Out of 2956 patients receiving sphincter-preserving surgery in only primary resection, 130 (4.4%) patients had anastomotic leakage. Traditional low anterior resection (tumor at middle rectum) (OR 2.384, P < 0.001), traditional low anterior resection (tumor at low rectum) (OR 1.968, P = 0.017) and intersphincteric resection (OR 5.468, P = 0.006) were significant independent risk factors for anastomotic leakage. Female gender (OR 0.557, P = 0.005), age ≥ 60 years (OR 0.684, P = 0.040), and preventive stoma (OR 0.496, P = 0.043) were significant independent protective factors. Body mass index, preoperative chemotherapy/radiotherapy, tumor size, and TNM stage did not independently affect the occurrence of anastomotic leakage. CONCLUSION: Robotic colorectal cancer surgery was safe and reliable and might have advantages in patients at high risk of anastomotic leakage.

VISTA-Ig ameliorates OXA-induced allergic dermatitis symptoms in mice.

BACKGROUND: Allergic dermatitis (AD) is a chronic inflammatory skin disease that a variety of immune cells are involved in the progression of AD. Among them, T cells are one of major players of AD pathogenesis. The V-domain Ig suppressor of T cell activation (VISTA) has been reported that it has a potential immunomodulatory for T cell response. OBJECTIVE: This study aimed to investigate immunomodulatory of recombinant VISTA-Ig fusion protein in AD mice model. METHODS: The model of AD was built with oxazolone (OXA) in BALB/c mice, then VISTA-Ig was used to treat AD by intraperitoneal (IP) injection. The ear thickness was measured by a digital thickness gauge. The ears tissues were collected and subjected to hematoxylin-eosin (H&E) and toluidine blue (TB) staining. The secretion levels of IL-4 and IgE in the serum were measured by enzyme linked immunosorbent assay (ELISA). The mRNA expression levels of inflammatory cytokines (IL-1ß, IL-6, IL-12, and INF-γ) in ear tissues were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). RESULTS: Treatment with VISTA-Ig successfully alleviated the symptoms of AD, such as erythema, horny substance, and swelling. The infiltration of inflammatory cells was significantly reduced following VISTA-Ig therapy. The secretion levels of IL-4 and IgE in the serum were significantly attenuated following treatment with VISTA-Ig. Additionally, VISTA-Ig observably down-regulated inflammatory cytokines expression in ear tissues. CONCLUSIONS & CLINICAL RELEVANCE: Taken together, our results showed that VISTA-Ig possessed the potential to be a novel immunomodulatory candidate drug against AD.

The role of N6-methyladenosine (m6A) modification in the regulation of circRNAs.

N6-methyladenosine (m6A), the most abundant modification in eukaryotic cells, regulates RNA transcription, processing, splicing, degradation, and translation. Circular RNA (circRNA) is a class of covalently closed RNA molecules characterized by universality, diversity, stability and conservatism of evolution. Accumulating evidence shows that both m6A modification and circRNAs participate in the pathogenesis of multiple diseases, such as cancers, neurological diseases, autoimmune diseases, and infertility. Recently, m6A modification has been identified for its enrichment and vital biological functions in regulating circRNAs. In this review, we summarize the role of m6A modification in the regulation and function of circRNAs. Moreover, we discuss the potential applications and possible future directions in the field.

Roles of circRNAs in the tumour microenvironment.

The tumour microenvironment (TME) constitutes the area surrounding the tumour during its development and has been demonstrated to play roles in cancer-related diseases through crosstalk with tumour cells. Circular RNAs (circRNAs) are a subpopulation of endogenous noncoding RNAs (ncRNAs) that are ubiquitously expressed in eukaryotes and have multiple biological functions in the regulation of cancer onset and progression. An increasing number of studies have shown that circRNAs participate in the multifaceted biological regulation of the TME. However, details on the mechanisms involved have remained elusive until now. In this review, we analyse the effects of circRNAs on the TME from various perspectives, including immune surveillance, angiogenesis, hypoxia, matrix remodelling, exo-circRNAs and chemoradiation resistance. Currently, the enormous potential for circRNA use in targeted therapy and as noninvasive biomarkers have drawn our attention. We emphasize the prospect of targeting circRNAs as an essential strategy to regulate TME, overcome cancer resistance and improve therapeutic outcomes.

Anatomical study of the left colic artery in laparoscopic-assisted colorectal surgery.

BACKGROUND: It is important for lymph node dissection around the inferior mesenteric artery (IMA) with preservation of the left colic artery (LCA) to be aware of the track and the length of the LCA. We aimed to investigate the branching pattern and trajectory of LCA and measure the distances from the root of the IMA to the origin of the LCA (D mm) and from the origin of LCA to intersection of LCA and IMV (d mm) during laparoscopic left-sided colorectal operations. METHODS: We analyzed 106 patients who underwent laparoscope-assisted left-side colorectal surgery during laparoscopic surgery. The branching patterns among the IMA, LCA, and sigmoidal trunk were evaluated; the trajectory of LCA was examined; the D mm and d mm were measured using a length of silk in the surgical operation. RESULTS: In 59.5% patients, the LCA arose independently from the sigmoidal trunk (type A); in 8.5% patients, the LCA and sigmoidal trunk arose from the IMA at the same point (type B); in 29.2% patients, the LCA and sigmoidal trunk had a common trunk (type C); the LCA did not exist in 2.8% (type D).The D mm and d mm for all cases ranged from 15.0 to 65.3 mm (median, 43.1 mm) and from 20.3 to 46.2 mm (median, 34.8 mm), respectively. 74.8% of the LCA went straight upper left and upward to proximal part of descending colon (type I), 25.2% went to the lower left at first, then turned to travel straight upward to proximal part of descending colon (type II). CONCLUSION: This study showed the anatomic variations of LCA during laparoscopic left-sided colorectal operation, which would help surgeons safely perform laparoscopic surgery in the left-side colon and rectum.

Exosomal circRNAs: biogenesis, effect and application in human diseases.

Exosomes have emerged as critical mediators of intercellular communication, both locally and systemically, by regulating a diverse range of biological processes between cells. Circular RNA (circRNA) is a novel member of endogenous noncoding RNAs with widespread distribution and diverse cellular functions. Recently, circular RNAs have been identified for their enrichment and stability in exosomes. In this review, we outline the origin, biogenesis and function of exosomal circRNAs as well as their roles in various diseases. Although their precise roles and mechanisms of gene regulation remain largely elusive, exosomal circRNAs have potential applications as disease biomarkers and novel therapeutic targets.

Effects of exosomes on pre-metastatic niche formation in tumors.

A pre-metastatic niche is a microenvironment prepared for the colonization of circulating tumor cells in specific organs. Exosomes are extracellular vesicles with a variety of biological functions. Exosomes play an irreplaceable role in the development of pre-metastatic niches, and mainly function as communication medium. In this review, we analyzed the effects of exosomes on pre-metastatic niches from various perspectives, including inflammation, immune response, angiogenesis, organotropism, matrix remodeling and biomarker expression. In particular, exosomes express programmed death ligand 1 (PD-L1) and cause the immune escape of tumor cells. The immunomodulatory effects of exosomes and their potential in liquid diagnosis have drawn our attention. The potential value of exosomes and pre-metastatic niches will be realized in the field of immunity therapy.

Serum CCL20 combined with IL-17A as early diagnostic and prognostic biomarkers for human colorectal cancer.

BACKGROUND: Noninvasive and effective methods of early diagnosis of colorectal cancer (CRC) are underexplored. Inflammation is known to play an important role in the tumor microenvironment of CRC. Therefore, the aim of this study was to elucidate novel inflammatory biomarkers related to early diagnosis and prognosis of CRC. METHODS: Based on the results from a multiplex assay and a pan-cancer screening of TCGA data with 18 cancer types, we identified several targeted biomarkers. We further confirmed these results using a trial cohort of 112 CRC patients and 151 controls (59 healthy donors, 52 colitis and 40 colorectal adenoma patients) by Elisa and immunohistochemistry (IHC). The biomarkers expression levels in CRC patients of different clinical stages were compared. The targeted biomarkers panel was developed using logistic regression model and was then validated using an independent cohort including 75 CRC patients and 90 controls (35 healthy donors, 20 colitis and 35 colorectal adenoma patients). Diagnostic accuracy was evaluated using area under the receiver-operating characteristic (ROC) curve and overall survival analysis was used for prognosis. Gene ontology (GO) analyses and Gene set enrichment analyses (GSEA) were performed to predict the function of the candidate biomarkers. RESULTS: CCL20 and IL-17A were identified as candidate biomarkers using multiplex assay and pan-cancer screening of TCGA data. Elisa and IHC demonstrated that both CCL20 and IL-17A levels were highly expressed in CRC patients, more especially in patients with advanced stage disease. A signature expression of the two biomarkers showed high diagnostic accuracy of CRC. Importantly, the diagnostic sensitivity and specificity were still satisfactory in the early stage and low carcinoembryonic antigen (CEA) level groups. Bioinformatics analysis revealed that CCL20 and IL-17A may be involved in CRC progression. In addition, the diagnostic performance of CCL20 and IL-17A in combination was superior to that of either marker alone. CONCLUSIONS: Serum CCL20 and IL-17A levels were identified as independent prognostic markers for CRC. The CCL20-IL-17A panel exhibited a good performance in the diagnosis of early stage CRC.

Effect of exosomal miRNA on cancer biology and clinical applications.

Exosomes, extracellular vesicles with diameters ranging from 30 to 150 nm, are widely present in various body fluids. Recently, microRNAs (miRNAs) have been identified in exosomes, the biogenesis, release, and uptake of which may involve the endosomal sorting complex required for transport (ESCRT complex) and relevant proteins. After release, exosomes are taken up by neighboring or distant cells, and the miRNAs contained within modulate such processes as interfering with tumor immunity and the microenvironment, possibly facilitating tumor growth, invasion, metastasis, angiogenesis and drug resistance. Therefore, exosomal miRNAs have a significant function in regulating cancer progression. Here, we briefly review recent findings regarding tumor-derived exosomes, including RNA sorting and delivering mechanism. We then describe the intercommunication occurring between different cells via exosomal miRNAs in tumor microenvironmnt, with impacts on tumor proliferation, vascularization, metastasis and other biological characteristics. Finally, we highlight the potential role of these molecules as biomarkers in cancer diagnosis and prognosis and tumor resistance to therapeutics.

Emerging role of exosome-derived long non-coding RNAs in tumor microenvironment.

Exosomes are extracellular vesicles released by many cell types and have been attributed for their roles in many diseases including cancer. Exosomes secreted by tumor cells and stromal cells are critical mediators of intercellular communication in tumor microenvironments. Long noncoding RNAs (lncRNAs) are selectively sorted into exosomes and can regulate cancer onset and progression in a variety of ways. In this review, we summarize the characteristics of exosomal lncRNAs and their dysregulation in multiple types of cancer. We provide an overview of current research on exosomal lncRNAs in tumor microenvironments, especially the functions of exosomal lncRNAs in regulating tumor biology. A deeper understanding of the role of exosomal lncRNAs in the tumor microenvironment may help provide new diagnostic and prognostic markers for cancer.

The Biological Effect and Clinical Application of Long Noncoding RNAs in Colorectal Cancer.

Colorectal cancer (CRC) is one of the most common malignancies in the world. Easier recurrence and metastasis is the main cause of mortality in CRC patients, and the markers applied for diagnosis and treatment of CRC is still urgently needed to early diagnose and evaluate therapeutic effect. Long noncoding RNA (lncRNA) is a class of noncoding RNA that the length is more than 200 nucleotides. With the development of sequencing technique about transcriptome, increasing lncRNAs are focused on their function and mechanism related to the nosogenesis and pathology of CRC. Recent studies report that lncRNAs acted as crucial role in CRC and could be as biomarker for CRC diagnosis and treatment. In this review, we display the regulation of lncRNA by interacting with DNA, RNA and protein and highlight the double role of lncRNAs as oncogene or anti-tumor gene involved in Wnt signaling pathway, p53 signaling pathway or others to be an regulator in CRC development. Lastly, we discuss some new finding of lncRNAs, especially lncRNA in exosome, which could be as potential markers for diagnosis and treatment of CRC in future.

Identification of liver metastasis-associated genes in human colon carcinoma by mRNA profiling.

OBJECTIVE: Liver metastasis, which contributes substantially to high mortality, is the most common recurrent mode of colon carcinoma. Thus, it is necessary to identify genes implicated in metastatic colonization of the liver in colon carcinoma. METHODS: We compared mRNA profiling in 18 normal colon mucosa (N), 20 primary tumors (T) and 19 liver metastases (M) samples from the dataset GSE49355 and GSE62321 of Gene Expression Omnibus (GEO) database. Gene ontology (GO) and pathways of the identified genes were analyzed. Co-expression network and protein-protein interaction (PPI) network were employed to identify the interaction relationship. Survival analyses based on The Cancer Genome Atlas (TCGA) database were used to further screening. Then, the candidate genes were validated by our data. RESULTS: We identified 22 specific genes related to liver metastasis and they were strongly associated with cell migration, adhesion, proliferation and immune response. Simultaneously, the results showed that C-X-C motif chemokine ligand 14 (CXCL14) might be a favorable prediction factor for survival of patients with colon carcinoma. Importantly, our validated data further suggested that lower CXCL14 represented poorer outcome and contributed to metastasis. Gene set enrichment analysis (GSEA) showed that CXCL14 was negatively related to the regulation of stem cell proliferation and epithelial to mesenchymal transition (EMT). CONCLUSIONS: CXCL14 was identified as a crucial anti-metastasis regulator of colon carcinoma for the first time, and might provide novel therapeutic strategies for colon carcinoma patients to improve prognosis and prevent metastasis.

LncRna CPS1-IT1 Suppresses Cell Proliferation, Invasion and Metastasis in Colorectal Cancer.

BACKGROUND/AIMS: Increasing evidence demonstrates that long non-coding RNAs (lncRNAs) regulate diverse cellular processes and cancer progression. Whether lncRNAs play any functional role in colorectal carcinoma (CRC) remains largely unknown. The aim of this study was to investigate the role of lncRNA CPS1 intronic transcript 1 (CPS1-IT1) in CRC. METHODS: Expression of CPS1-IT1 was initially assessed in human CRC tissues and in a series of CRC cell lines. The correlations between CPS1-IT1 levels and survival outcomes were analyzed to elucidate the clinical significance of CPS1-IT1 in CRC. The underlying mechanisms of CPS1-IT1 in CRC were analyzed through in vitro and in vivo functional assays. RESULTS: Expression of CPS1-IT1 was significantly decreased in CRC tissues and cell lines, and patients with low CPS1-IT1 expression had poor survival outcomes. The results of in vitro assays revealed that CPS1-IT1 significantly reduced cell proliferation, migration and invasion capacities and accelerated cell apoptosis, thereby suppressing epithelial-mesenchymal transition (EMT). An in vivo animal model also demonstrated the tumor-suppressive role of CPS1-IT1. CONCLUSION: In this study, we found that CPS1-IT1 has a tumor-suppressive role in CRC. Our data suggest that CPS1-IT1 could be used as a new prognostic biomarker and therapeutic target for CRC.