Anus preservation in low rectal adenocarcinoma based on MMR/MSI status (APRAM): a study protocol for a randomised, controlled, open-label, multicentre phase III trial.

BACKGROUND: Anus preservation has been a challenge in the treatment of patients with low rectal adenocarcinoma (within 5 cm from the anal verge) because it is difficult to spare the anus with its functioning sphincter complex under the safe margin of tumour resection. Patients with dMMR/MSI-H can achieve a favourable complete response (CR) rate by using a single immune checkpoint inhibitor. For patients with pMMR/MSS/MSI-L, intensified neoadjuvant three-drug chemotherapy may be the preferred option for anal preservation. In addition, the watch and wait (W&W) strategy has been proven safe and feasible for patients with rectal cancer who achieve a clinical complete response (cCR). Therefore, we initiated this clinical trial to explore the optimal neoadjuvant treatment pattern for patients with low locally advanced rectal cancer (LARC) with different MMR/MSI statuses, aiming to achieve a higher cCR rate with the W&W strategy and ultimately provide more patients with a chance of anus preservation. METHODS: This is a randomised, controlled, open-label, multicentre phase III trial. Patients with clinical stage T2-4 and/or N + tumours located within 5 cm from the anal verge are considered eligible. Based on the results of pathological biopsy, the patients are divided into two groups: dMMR/MSI-H and pMMR/MSS. Patients in the dMMR/MSI-H group will be randomly allocated in a 1:1 ratio to either arm A (monoimmunotherapy) or arm B (short-course radiotherapy followed by monoimmunotherapy). Patients in the pMMR/MSS group will be initially treated with long-term pelvic radiation with concurrent capecitabine combined with irinotecan. Two weeks after the completion of chemoradiotherapy (CRT), the patients will be randomly allocated in a 1:1 ratio to arm C (XELIRI six cycle regime) or arm D (FOLFIRINOX nine cycle regime). The irinotecan dose will be adjusted according to the UGT1A1-genotype. After treatment, a comprehensive assessment will be performed to determine whether a cCR has been achieved. If achieved, the W&W strategy will be adopted; otherwise, total mesorectal excision (TME) will be performed. The primary endpoint is cCR with the maintenance of 12 months at least, determined using digital rectal examination, endoscopy, and rectal MRI or PET/CT as a supplementary method. DISCUSSION: APRAM will explore the best anus preservation model for low LARC, combining the strategies of consolidation chemotherapy, immunotherapy, and short-course radiotherapy, and aims to preserve the anus of more patients using W&W. Our study provides an accurate individual treatment mode based on the MMR/MSI status for patients with low LARC, and more patients will receive the opportunity for anus preservation under our therapeutic strategy, which would transform into long-term benefits. TRIAL REGISTRATION: Clinicaltrials.gov NCT05669092 (Registered 28th Nov 2022).

Unraveling Colorectal Cancer and Pan-cancer Immune Heterogeneity and Synthetic Therapy Response Using Cuproptosis and Hypoxia Regulators by Multi-omic Analysis and Experimental Validation.

Cuproptosis, a new type of programmed cell death (PCD), is closely related to cellular tricarboxylic acid cycle and cellular respiration, while hypoxia can modulate PCD. However, their combined contribution to tumor subtyping remains unexplored. Here, we applied a multi-omics approach to classify TCGA_COADREAD based on cuproptosis and hypoxia. The classification was validated in three colorectal cancer (CRC) cohorts and extended to a pan-cancer analysis. The results demonstrated that pan-cancers, including CRC, could be divided into three distinct subgroups (cuproptosis-hypoxia subtypes, CHSs): CHS1 had active metabolism and poor immune infiltration but low fibrosis; CHS3 had contrasting characteristics with CHS1; CHS2 was intermediate. CHS1 may respond well to cuproptosis inducers, and CHS3 may benefit from a combination of immunotherapy and anti-fibrosis/anti-hypoxia therapies. In CRC, the CHSs also showed a significant difference in prognosis and sensitivity to classic drugs. Organoid-based drug sensitivity assays validated the results of transcriptomics. Cell-based assays indicated that masitinib and simvastatin had specific effects on CHS1 and CHS3, respectively. A user-friendly website based on the classifier was developed (https://fan-app.shinyapps.io/chs_classifier/) for accessibility. Overall, the classifier based on cuproptosis and hypoxia was applicable to most pan-cancers and could aid in personalized cancer therapy.

Serum lncRNA-UFC1 as a potential biomarker for diagnosis and prognosis of pancreatic cancer.

Early diagnosis is important to improve the prognosis of pancreatic cancer (PC). Identifying potential biomarkers is essential for the monitoring and treatment of PC. The long noncoding RNA (lncRNA) UFC1 has been identified as an oncogenic factor in many cancers. However, the expression of UFC1 and its potential role in diagnosis and prognosis of PC remain largely unknown. The present study aimed to investigate the role of serum UFC1 in diagnosis and prognosis. The results indicated that serum UFC1 expression was relatively higher in PC patients than that in healthy volunteers. ROC curve analysis revealed that the serum UFC1 levels could distinguish PC patients from healthy controls, with an AUC value of 0.810. In addition, the serum UFC1 expression level was associated with lymph nodes metastasis, distant metastasis, and clinical stage. Kaplan-Meier analysis indicated that patients with high UFC1 expression exhibited shorter progression-free survival (PFS) and overall survival (OS) than those with low UFC1 expression. Multivariate analysis demonstrated that clinical stage and UFC1 expression level were significant, independent prognostic factors in PC patients. Our data demonstrate that serum UFC1 might serve as a potential biomarker for diagnosis and prognosis of PC.

IGF-1 from adipose-derived mesenchymal stem cells promotes radioresistance of breast cancer cells.

PURPOSE: The aim of this study was to investigate effects of adipose-derived mesenchymal stem cells (AMSCs) on radioresistance of breast cancer cells. MATERIALS AND METHODS: MTT assays were used to detect any influence of AMSC supernatants on proliferation of breast cancer cells; cell migration assays were used to determine the effect of breast cancer cells on the recruitment of AMSCs; the cell survival fraction post-irradiation was assessed by clonogenic survival assay; γ-H2AX foci number post-irradiation was determined via fluorescence microscopy; and expression of IGF-1R was detected by Western blotting. RESULTS: AMSC supernatants promoted proliferation and radioresistance of breast cancer cells. Breast cancer cells could recruit AMSCs, especially after irradiation. IGF-1 derived from AMSCs might be responsible for the radioresistance of breast cancer cells. CONCLUSIONS: Our results suggest that AMSCs in the tumor microenvironment may affect the outcome of radiotherapy for breast cancer in vitro.

Meta-analysis of outcomes compared between robotic and laparoscopic gastrectomy for gastric cancer.

This meta-analysis was performed to evaluate and compare the outcomes of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for treating gastric cancer. A systematic literature search was carried out using the PubMed database, Web of Knowledge, and the Cochrane Library database to obtain comparative studies assessing the safety and efficiency between RG and LG in May, 2013. Data of interest were analyzed by using of Review Manager version 5.2 software (Cochrane Collaboration). A fixed effects model or random effects model was applied according to heterogeneity. Seven papers reporting results that compared robotic gastrectomy with laparoscopic gastrectomy for gastric cancer were selected for this meta-analysis. Our meta- analysis included 2,235 patients with gastric cancer, of which 1,473 had undergone laparoscopic gastrectomy, and 762 had received robotic gastrectomy. Compared with laparoscopic gastrectomy, robotic gastrectomy was associated with longer operative time but less blood loss. There were no significant difference in terms of hospital stay, total postoperative complication rate, proximal margin, distal margin, numbers of harvested lymph nodes and mortality rate between robotic gastrectomy and laparoscopic gastrectomy. Our meta-analysis showed that robotic gastrectomy is a safe technique for treating gastric cancer that compares favorably with laparoscopic gastrectomy in short term outcomes. However, the long term outcomes between the two techniques need to be further examined.

[Radiation-induced G2 phase arrest may contribute to the radioresistance of breast cancer stem cells].

OBJECTIVE: To investigate radiation-induced cell cycle changes of human breast cancer stem cells enriched by suspension culture. METHODS: The tumorigenicity of human breast cancer stem cell line MCF-7 cultured in serum-free media was confirmed in NOD/SCID mice, and the radiosensitivity of the cells was tested by clone formation assay following radiation exposure. Flow cytometry was performed to evaluate radiation-induced cell cycle changes, and the protein expression of pCDC25C (ser216) was measured by Western blotting. RESULTS: After the exposure to 2 Gy radiation, the survived fraction of the cells in suspension culture and those in adherent culture was 0.856 ∓ 0.061 and 0.783 ∓ 0.097, respectively, and the cells in suspension culture showed an obviously greater capacity of tumorigenicity in NOD/SCID mice. The radiation exposure resulted in an obvious increase in the proportion of G2 phase cells from (22.03 ∓ 2.12)% to (45.83 ∓ 2.25)% and significantly increased the expression of pCDC25C (ser216). CONCLUSION: Radiation- induced G2 phase arrest may contribute to the resistance of the breast cancer stem cells to radiotherapy.

[Effect of shRNAmir lentiviral vector-mediated COX-2 silencing on the radiosensitivity of nasopharyngeal carcinoma cells].

OBJECTIVE: To evaluate the effect of COX-2 silencing on the radiosensitivity of a nasopharyngeal carcinoma (NPC) cell line C666-1. METHODS: Anti-COX-2 C666-1 cell line with COX-2 gene silencing mediated by shRNAmir lentiviral vector and the control cell line Anti-GL-2 C666-1 were exposed to various radiation doses. The clonogenic survival assay and curve fitting was used to calculate the radiobiological parameters and the sensitization enhancement ratio after the radiation. Cell cycle changes were assessed after the exposure by flow cytometric analysis. In a BALB/c nude mouse model, the growth curve of the xenografts was generated and the tumor growth inhibition rate was calculated. RESULTS: Compared with the control cells, Anti-COX-2 C666-1 cells showed obviously lowered values of SF2, D0 and Dq but significantly increased α/ß with a sensitivity enhancement ratio of 1.4014. COX-2 gene silencing increased the inhibition rate of the tumor xenografts after the radiation, and caused also decreased percentage of G2/M arrest resulting from the exposure. CONCLUSION: Stable COX-2 silencing in NPC cells can improve the effect of radiotherapy both in vitro and in vivo. By changing the radiobiological parameters, genetically based COX-2 inhibitor may be a potentially promising radiosensitizer of NPC.

[Effect of gemcitabine in enhancing the radiosensitivity of HepG2 hepatoma cells and the possible mechanism].

OBJECTIVE: To evaluate the effect of gemcitabine in enhancing the radiosensitivity of hepatoma cell line HepG2 and explore its mechanisms. METHODS: Clonogenic survival assay is employed to calculate the ratios of L-Q model radiation biology parameters and radiosensitization after different doses of irradiation. Flow cytometry was used to detect the changes in HepG2 cell cycle and apoptosis rate after gemcitabine treatment and radiation exposure. RESULTS: The survival fraction at 2 Gy of HepG2 cells treated with gemcitabine was significantly lower, and the value of alpha was significantly higher than those of untreated cells. GEM treatment increased the percentage of radiation-induced G0/G1 phase cells and cell apoptosis. CONCLUSION: Gemcitabine can significantly enhance the radiosensitivity of HepG2 cells by enhancing radiation-induced cell cycle arrest in G0/G1 phase and cell apoptosis.