The role of adjuvant chemotherapy in rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy.

Background: Neoadjuvant chemoradiotherapy has emerged as the established treatment for locally advanced rectal cancer. Nevertheless, there remains a debate regarding the necessity of adjuvant chemotherapy for patients with locally advanced rectal cancer who exhibit a favorable tumor response (ypT0-2N0) after neoadjuvant chemoradiotherapy and surgery. Thus, the objective of this study is to investigate the impact of adjuvant chemotherapy on the oncological prognosis of rectal cancer patients who have a good response to neoadjuvant chemoradiotherapy. Materials and methods: The study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Articles were searched in the Web of Science, PubMed, and Cochrane Library databases. The primary outcomes assessed were 5-year overall survival, disease-free survival, cancer-specific survival, recurrence-free survival, local recurrence, and distant metastasis. The data was summarized using a random effects model. Results: A meta-analysis was conducted using 18 retrospective studies published between 2009 and 2023. The studies included 9 from China and 5 from Korea, involving a total of 6566 patients with ypT0-2N0 rectal cancer after neoadjuvant chemoradiotherapy. The pooled data revealed that adjuvant chemotherapy significantly improved 5-year overall survival (OR=1.75, 95% CI: 1.15-2.65, P=0.008), recurrence-free survival (OR=1.73, 95% CI: 1.20-2.48, P=0.003), and reduced distant metastasis (OR=0.68, 95% CI: 0.51-0.92, P=0.011). However, adjuvant chemotherapy did not have a significant effect on disease-free survival, cancer-specific survival, and local recurrence in ypT0-2N0 rectal cancer. Subgroup analysis indicated that adjuvant chemotherapy was beneficial in improving overall survival for ypT1-2N0 rectal cancer (OR=1.89, 95% CI: 1.13-3.19, P=0.003). Conclusion: The findings of the meta-analysis suggest that adjuvant chemotherapy may provide benefits in terms of oncological outcomes for rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy and radical surgery. However, further prospective clinical studies are needed to confirm these findings.

BVES-AS1 suppresses the colorectal cancer progression via the miR-1269a/b-SVEP1-PI3K/AKT axis.

BACKGROUND: Numerous studies have indicated the engagement of long non-coding RNA (lncRNA) in various cancer types, including colorectal cancer (CRC). However, the functional and mechanistic roles of lncRNAs in CRC remain largely elusive. OBJECTIVES: The aim of this study was to explore the function and mechanism of lncRNA BVES-AS1 in CRC. MATERIAL AND METHODS: The expression levels of BVES-AS1 were validated in CRC tissues and paired normal samples using quantitative real-time polymerase chain reaction (qPCR) Subsequently, the biological functions of BVES-AS1 in CRC cells were investigated both in vitro and in vivo. Various experimental techniques such as western blot, fluorescence in situ hybridization, RNA-sequencing (RNA-seq), biotin-labeled miRNA pulldown assay, dual-luciferase reporter gene assay, and RNA-protein immunoprecipitation (RIP) assay were employed to elucidate the potential mechanism of BVES-AS1. RESULTS: The findings of this study demonstrated that BVES-AS1 expression was downregulated in CRC tissues compared to normal tissues, and its expression level was associated with tumor infiltration and tumor-nodule-metastasis (TNM) stage. Furthermore, BVES-AS1 was found to suppress CRC cell proliferation, migration and metastasis both in vitro and in vivo. Mechanistically, BVES-AS1 acted as a sponge for miR-1269a and miR-1269b, thereby regulating SVEP1. Additionally, the silencing of SVEP1 activated the PI3K/AKT pathway. CONCLUSIONS: These results suggest that BVES-AS1 plays a crucial role in the progression of CRC through the miR-1269a/b-SVEP1-PI3K/AKT axis, providing new insights into the therapeutic strategies for CRC.

Effect of adjuvant chemotherapy on the oncological outcome of rectal cancer patients with pathological complete response.

BACKGROUND: Locally advanced rectal cancer is typically treated using a combination of neoadjuvant chemoradiotherapy and total mesorectal resection. While achieving pathological complete response following neoadjuvant chemoradiotherapy has been recognized as a positive prognostic factor in oncology, the necessity of adjuvant chemotherapy for locally advanced rectal cancer patients with pathological complete response after surgery remains uncertain. The objective of this meta-analysis was to examine the impact of adjuvant chemotherapy on the oncological outcomes of rectal cancer patients who attain pathological complete response after neoadjuvant chemoradiotherapy. METHODS: This meta-analysis followed the guidelines outlined in the preferred reporting items for systematic review and meta-analysis (PRISMA). The Web of Science, PubMed, and Cochrane Library databases were systematically searched to identify relevant literature. RESULTS: A total of 34 retrospective studies, including 9 studies from the NCBD database, involving 31,558 patients with pathological complete response rectal cancer, were included in the meta-analysis. The included studies were published between 2008 and 2023. The pooled analysis demonstrated that adjuvant chemotherapy significantly improved overall survival (HR = 0.803, 95% CI 0.678-0.952, P = 0.011), and no heterogeneity was observed (I2 = 0%). Locally advanced rectal cancer patients with pathological complete response who underwent adjuvant chemotherapy exhibited a higher 5-year overall survival rate compared to those who did not receive adjuvant chemotherapy (OR = 1.605, 95% CI 1.183-2.177, P = 0.002). However, the analysis also revealed that postoperative ACT did not lead to improvements in disease-free survival and recurrence-free survival within the same patient population. Subgroup analysis indicated that pathological complete response patients with clinical stage T3/T4, lymph node positivity, and younger than 70 years of age may benefit from adjuvant chemotherapy in terms of overall survival. CONCLUSIONS: The findings of this meta-analysis suggest that adjuvant chemotherapy has a beneficial effect on improving overall survival among rectal cancer patients with pathological complete response. However, no such association was observed in terms of disease-free survival and recurrence-free survival.

Body composition parameters combined with blood biomarkers and magnetic resonance imaging predict responses to neoadjuvant chemoradiotherapy in locally advanced rectal cancer.

Aim: To investigate whether body composition parameters combined with systemic inflammatory markers and magnetic resonance imaging (MRI) can predict the pathological complete response (pCR) following neoadjuvant chemoradiotherapy (NCRT) in locally advanced rectal cancer (LARC). Methods: A retrospective analysis of data on LARC patients treated with NCTR and radical surgery between January 2013 and May 2023 was performed. Body composition parameters were assessed by measuring the skeletal muscle index (SMI), subcutaneous adipose index (SAI), and visceral adipose index (VAI) at the third lumbar vertebra level by computed tomography (CT). Inflammatory markers such as neutrophil to lymphocyte ratio (NLR) were obtained from laboratory tests performed prior to NCRT. MRI was conducted to evaluate MRI tumor regression grading (mrTRG). Logistic regression analyses were employed to identify factors affecting the pCR. The risk score of pCR was computed by a nomogram. The discrimination of the nomogram was determined using C-index and calibration curve. Results: Two hundred and ninety-one patients with LARC were enrolled in the study, 55 (18.9%) of whom achieved pCR after NCRT. Multivariate analysis suggested that pre-NCRT NLR≥2.6 (OR=0.378, 95% CI 0.164-0.868, P=0.022), mrTRG 3-5 (OR=0.256, 95%CI 0.121-0.54, P<0.001), and pre-NCRT L-SMI (OR=0.292, 95% CI 0.097-0.883, P=0.029) were independent risk factors for pCR. ROC curves analysis demonstrated that the performance of mrTRG combined with pre-NCRT NLR and pre-NCRT L-SMI in predicting pCR was significantly improved compared with mrTRG alone (AUC: 0.763 vs. 0.667). Additionally, mrTRG 3-5 (OR=0.375, 95% CI 0.219-0.641, P<0.001) was also an independent predictor for poor tumor regression. Conclusion: The pathological complete response of neoadjuvant chemoradiotherapy in locally advanced rectal cancer can be effectively predicted by combining the body composition parameters with blood biomarkers and magnetic resonance imaging.

CircGPRC5A enhances colorectal cancer progress by stabilizing PPP1CA and inducing YAP dephosphorylation.

BACKGROUND: With the advancements in bioinformatic technology, an increasing number of circular RNAs (circRNAs) have been discovered and their crucial roles in the development and progression of various malignancies have been confirmed through multiple pathways. However, the specific mechanisms involving protein-binding circRNAs in colorectal cancer (CRC) remain largely unexplored. METHODS: Differential circRNA expression was assessed using a human circRNA microarray in five CRC tissue and paired normal samples. CircGPRC5A expression was then confirmed in the CRC tissues and paired normal samples using qRT-PCR. The biological function of circGPRC5A in CRC were studied in vitro and in vivo. Western blotting, fluorescence in situ hybridization, immunofluorescence, RNA pulldown, mass spectrometry, immunoprecipitation, quantitative phosphoproteomics, and RNA-binding protein immunoprecipitation assays were used to study circGPRC5A. RESULTS: Our analysis revealed that circGPRC5A expression was higher in CRC tissues compared to normal tissues and was associated with tumor size, tumor stage and lymph node status. CircGPRC5A promoted CRC cell proliferation, migration, and metastasis in vitro and in vivo. CircGPRC5A could stabilize PPP1CA protein by inhibiting the binding between UBA1 and PPP1CA, and increasing YAP dephosphorylation. CONCLUSIONS: Our study revealed that circGPRC5A plays an essential function in CRC progression by stabilizing PPP1CA protein and enhancing YAP dephosphorylation. CircGPRC5A could act as a novel and potential target for CRC.

Cancer-associated fibroblast-related prognostic signature predicts prognosis and immunotherapy response in pancreatic adenocarcinoma based on single-cell and bulk RNA-sequencing.

Cancer-associated fibroblasts (CAFs) influence many aspects of pancreatic adenocarcinoma (PAAD) carcinogenesis, including tumor cell proliferation, angiogenesis, invasion, and metastasis. A six-gene prognostic signature was constructed for PAAD based on the 189 CAF marker genes identified in single-cell RNA-sequencing data. Multivariate analyses showed that the risk score was independently prognostic for survival in the TCGA (P < 0.001) and ICGC (P = 0.004) cohorts. Tumor infiltration of CD8 T (P = 0.005) cells and naïve B cells (P = 0.001) was greater in the low-risk than in the high-risk group, with infiltration of these cells negatively correlated with risk score. Moreover, the TMB score was lower in the low-risk than in the high-risk group (P = 0.0051). Importantly, patients in low-risk group had better immunotherapy responses than in the high-risk group in an independent immunotherapy cohort (IMvigor210) (P = 0.039). The CAV1 and SOD3 were highly expressed in CAFs of PAAD tissues, which revealed by immunohistochemical staining. In summary, this comprehensive analysis resulted in the development of a novel prognostic signature, which was associated with immune cell infiltration, drug sensitivity, and TMB, and could predict the prognosis and immunotherapy response of patients with PAAD.

Effect of neoadjuvant chemotherapy combined with arterial chemoembolization on short-term clinical outcome of locally advanced gastric cancer.

BACKGROUND: The purpose of this study was to explore the short-term efficacy and safety of neoadjuvant chemotherapy combined with arterial chemoembolization for locally advanced gastric cancer (LAGC). METHODS: We retrospectively analyzed the clinical data of 203 patients with LAGC who received neoadjuvant therapy from June 2019 to December 2021. The patients were divided into a neoadjuvant chemotherapy combined with arterial chemoembolization group (combined group, n = 102) and a neoadjuvant chemotherapy group (conventional group, n = 101). The adverse events of chemotherapy, postoperative complications and pathological complete response (pCR) rate were compared between the two groups. Univariate and multivariate analyses were performed to evaluate the potential factors affecting pCR. RESULTS: A total of 78.8% of the patients were in clinical stage III before neoadjuvant therapy. A total of 52.2% of the patients underwent surgery after receiving two cycles of neoadjuvant therapy. There were 21.2% patients with ≥ grade 3 (CTCAE 4.0) adverse events of chemotherapy and 11.3% patients with Clavien-Dindo classification ≥ grade 3 postoperative complications. Compared with the conventional group, the combination group did not experience an increase in the adverse events of chemotherapy or postoperative complications. The pCR rate in the combined group was significantly higher than that in the conventional group (16.7% vs. 4.95%, P = 0.012). The multivariate analysis showed that arterial chemoembolization, pre-treatment neutrophil-to-lymphocyte ratio (NLR) and pre-treatment platelet-to-lymphocyte ratio (PLR) were independent factors affecting pCR. CONCLUSION: Neoadjuvant chemotherapy combined with arterial chemoembolization contributed to improving the pCR rate of LAGC patients. Arterial chemoembolization, pre-treatment NLR and pre-treatment PLR were also predictors of pCR.

LncRNA HOXB-AS4 promotes proliferation and migration of colorectal cancer via the miR-140-5p/hdac7 axis.

Long noncoding RNAs (lncRNA) have a critical role in colorectal cancer (CRC) development and progression. However, the role of the lncRNA HOXB-AS4 in CRC remains unclear. In this study, we found that HOXB-AS4 was markedly upregulated in tumor tissues compared to precancerous tissues. Loss-of-function assays in HT29 and SW480 cells confirmed that knockdown of HOXB-AS4 inhibited proliferation, migration, and promoted apoptosis. In addition, HOXB-AS4 was shown to regulate histone deacetylase 7 (HDAC7) expression by acting as a molecular sponge to bind to and adsorb miR-140-5p. These findings were confirmed by the dual-luciferase reporter assay. Functional recovery experiments further demonstrated the crucial role of the HOXB-AS4/miR-140-5p/HDAC7 axis in modulating the malignant phenotype of CRC cells. Collectively, our data suggested that HOXB-AS4 regulated the malignant tumor aggression of HT29 and SW480 cells through the miR-140-5p/HDAC7 axis and PI3K/AKT signaling pathway. Our study provides novel insights into the mechanism of action of HOXB-AS4 in CRC and highlights its potential use as a targeted therapy.

Promotive role of USP29-mediated deubiquitination in malignant proliferation of colorectal cancer cells via the KIAA1429/SOX8 axis.

Colorectal cancer (CRC) is regarded as one of the most prevalent neoplasms worldwide, and ubiquitination and N6-methyladenosine (m6A) modification regulate the outgrowth of multiple cancers. This study attempted to explore the effect of ubiquitin-specific peptidases 29 (USP29) on the malignant proliferation of CRC cells via stabilizing Vir-like m6A methyltransferase associated (VIRMA/KIAA1429). First, upregulations of USP29, KIAA1429, and SRY-box transcription factor 8 (SOX8) were found in CRC tissues and cells through real-time quantitative polymerase chain reaction and Western blotting. After transfection of si-USP29, the proliferation of CRC cells was evaluated by the cell counting kit-8, colony formation and 5-ethynyl-2'-deoxyuridine assays, and we observed that depletion of USP29 inhibited the proliferation of CRC cells. Co-immunoprecipitation confirmed the binding of USP29 to KIAA1429. Mechanically, USP29 mediated deubiquitination to stabilize the protein levels of KIAA1429, and KIAA1429 promoted the stability of SOX8 mRNA through m6A modification. Moreover, overexpression of KIAA1429 or SOX8 reversed the inhibitory effects of USP29 depletion on CRC cell proliferation. Finally, the xenograft tumor model revealed the promotive role of USP29 in the proliferation of CRC cells in vivo. Altogether, USP29 facilitates the malignant proliferation of CRC cells via upregulating the KIAA1429/SOX8 axis.

Long noncoding RNA LINC01606 protects colon cancer cells from ferroptotic cell death and promotes stemness by SCD1-Wnt/ß-catenin-TFE3 feedback loop signalling.

BACKGROUND: Ferroptosis is principally caused by iron catalytic activity and intracellular lipid peroxidation. Long noncoding RNAs (lncRNAs) play crucial roles in tumorigenesis. However, the potential interplay between lncRNA LINC01606 and ferroptosis in colon cancer remains elusive. METHODS: The expression level of LNC01606 in colon cancer tissue was detected by quantitative real-time polymerase chain reaction. The functional role of LNC01606 was investigated by gain- and loss-of-function assays both in vitro and in vivo. The LINC01606-SCD1-Wnt/ß-catenin-TFE3 axis were screened and validated by DNA/RNA pull down, gas chromatography-mass spectrometry, RNA immunoprecipitation and dual-luciferase reporter. RESULTS: The expression of lncRNA LINC01606 was frequently upregulated in human colon cancer and strongly associated with a poor prognosis. LINC01606 functioned as an oncogene and promotes colon cancer cell growth, invasion and stemness both in vitro and in vivo. Moreover, LINC01606 protected colon cancer cells from ferroptosis by decreasing the concentration of iron, lipid reactive oxygen species, mitochondrial superoxide and increasing mitochondrial membrane potential. Mechanistically, LINC01606 enhanced the expression of stearoyl-CoA desaturase 1 (SCD1), serving as a competing endogenous RNA to modulate miR-423-5p expression, subsequently activating the canonical Wnt/ß-catenin signaling, and transcription factor binding to IGHM enhancer 3 (TFE3) increased LINC01606 transcription after recruitment to the promoter regions of LINC01606. Furthermore, we confirmed that upregulated LINC01606 and Wnt/ß-catenin formed a positive feedback regulatory loop, further inhibiting ferroptosis and enhancing stemness. CONCLUSIONS: LINC01606 functions as an oncogene to facilitate tumor cell stemness, proliferation and inhibit ferroptosis and is a promising therapeutic target for colon cancer.

PRDX2 promotes the proliferation of colorectal cancer cells by increasing the ubiquitinated degradation of p53.

Colorectal cancer is the most common gastrointestinal cancer and causes severe damage to human health. PRDX2 is a member of the peroxiredoxin family reported to have a high level of expression in colorectal cancer. However, the mechanisms by which PRDX2 promotes the proliferation of colorectal cancer are still unclear. Here, the results indicated that PRDX2 expression was upregulated in colorectal cancer and closely correlated with poor prognosis. Functionally, PRDX2 promoted the proliferation of colorectal cancer cells. Mechanistically, PRDX2 could bind RPL4, reducing the interaction between RPL4 and MDM2. These findings demonstrate that the oncogenic property of PRDX2 may be attributed to its regulation of the RPL4-MDM2-p53 pathway, leading to p53 ubiquitinated degradation.