Vasorin (VASN) overexpression promotes pulmonary metastasis and resistance to adjuvant chemotherapy in patients with locally advanced rectal cancer.

BACKGROUND: LARC patients commonly receive adjuvant therapy, however, hidden micrometastases still limit the improvement of OS. This study aims to investigate the impact of VASN in rectal cancer with pulmonary metastasis and understand the underlying molecular mechanisms to guide adjuvant chemotherapy selection. METHODS: Sequencing data from rectal cancer patients with pulmonary metastasis from Sun Yat-sen University Cancer Center (SYSUCC) and publicly available data were meticulously analyzed. The functional role of VASN in pulmonary metastasis was validated in vivo and in vitro. Coimmunoprecipitation (co-IP), immunofluorescence, and rescue experiments were conducted to unravel potential molecular mechanisms of VASN. Moreover, VASN expression levels in tumor samples were examined and analyzed for their correlations with pulmonary metastasis status, tumor stage, adjuvant chemotherapy benefit, and survival outcome. RESULTS: Our study revealed a significant association between high VASN expression and pulmonary metastasis in LARC patients. Experiments in vitro and in vivo demonstrated that VASN could promote the cell proliferation, metastasis, and drug resistance of colorectal cancer. Mechanistically, VASN interacts with the NOTCH1 protein, leading to concurrent activation of the NOTCH and MAPK pathways. Clinically, pulmonary metastasis and advanced tumor stage were observed in 90% of VASN-positive patients and 53.5% of VASN-high patients, respectively, and VASN-high patients had a lower five-year survival rate than VASN-low patients (26.7% vs. 83.7%). Moreover, the Cox analysis and OS analysis indicated that VASN was an independent prognostic factor for OS (HR = 7.4, P value < 0.001) and a predictor of adjuvant therapy efficacy in rectal cancer. CONCLUSIONS: Our study highlights the role of VASN in decreasing drug sensitivity and activating the NOTCH and MAPK pathways, which leads to tumorigenesis and pulmonary metastasis. Both experimental and clinical data support that rectal cancer patients with VASN overexpression detected in biopsies have a higher risk of pulmonary metastasis and adjuvant chemotherapy resistance.

[Advances in the application of minimal residual disease in non-metastatic colorectal cancer].

In recent years, the application of minimal residual disease (MRD) in solid tumors has gained widespread attention. MRD typically refers to the presence of residual cancer cells that remain undetectable by imaging after curative treatments, such as surgical resection. The presence of MRD post-surgery is significantly associated with an increased risk of tumor recurrence. In colorectal cancer, circulating tumor DNA (ctDNA) serves as an effective marker for assessing MRD, particularly in non-metastatic (stages I-III) colorectal cancer. As a real-time, accurate, and convenient biomarker, ctDNA can effectively predict tumor recurrence, guide postoperative adjuvant chemotherapy decisions, and provide crucial information for recurrence monitoring. The application prospects of ctDNA detection technology are vast, promising more precise and individualized treatment plans for colorectal cancer patients. This article comprehensively analyzes the progress in the application of ctDNA for detecting MRD in non-metastatic colorectal cancer patients, elaborates on its guiding role in clinical treatment decisions, and envisions the future development directions in this field.

[Effect of plasminogen activator urokinase receptor gene on the activation and apoptosis of neutrophil].

Objective: To investigate the effect of plasminogen activator urokinase receptor (PLAUR) gene on neutrophil activation and apoptosis in neutrophil-like cell model. Methods: Human acute myeloid leukemia cell line HL60 was cultured in vitro and induced to differentiate into neutrophil-like cells by all-trans retinoic acid (ATRA). Lentiviral vectors interfering with human PLAUR gene was constructed and transfected into neutrophil-like cells (siRNA group). The phosphate buffer saline (PBS) group (untransfected neutrophil-like cells) and normal blank control group (NC group) (neutrophil-like cells transfected with blank plasmid) were used as controls (n=3). After starvation culture and addition of interleukin-17 afterwards in these 3 groups, the expression of CD11b on the cell membrane was detected by flow cytometry, and the levels of myeloperoxide (MPO) and extracellular neutrophil traps (NETs) in the supernatant were detected by enzyme-linked immunosorbent assay (ELISA) to investigate the activation of neutrophil-like cells. The apoptosis was detected by flow cytometry with annexin V/propidium iodide (PI) double staining and the expressions of apoptosis-related proteins caspase-3, bax and bcl-2 were detected by Western blotting. Results: The expression of CD11b in siRNA group (32.37±8.17) was lower than that in PBS group (46.27±1.54) and NC group (53.07±8.14) (P<0.05) by flow cytometry. The levels of MPO and NETs (33.37±1.11, 57.69±3.03) in the supernatant of siRNA group were significantly lower than those in PBS group (41.64±2.20, 77.60±4.33) and NC group (40.84±5.11, 76.15±2.10) (P<0.05). Flow cytometry with annexin V/PI showed that the expression of apoptosis in siRNA group (20.42%±2.45%) was significantly higher than that in PBS group (11.91%±2.23%) and NC group (11.13%±2.56%) (P<0.05). The relative expression of caspase-3 protein and bax protein (0.84±0.05, 0.83±0.04) in siRNA group was significantly higher than that in PBS group (0.68±0.02, 0.63±0.08) and NC group (0.71±0.01, 0.66±0.10) (P<0.05), and the relative expression of anti-apoptosis protein bcl-2 decreased in siRNA group (0.38±0.02) than in PBS group (0.73±0.05) and NC group (0.69±0.06) (P<0.05). Conclusion: PLAUR promotes the activation of neutrophil-like cells and inhibits the apoptosis.