Introduction

Ninjurin1 (Ninj1), a transmembrane protein, has been implicated in exhibiting dual roles, both pro-inflammatory and anti-inflammatory, in the pathogenesis of inflammatory diseases.

Aims & Methods

The objective of this study was to examine the involvement of Ninj1 in the development of colitis-associated colon tumor, as well as its potential association with sex hormones. Male and female mice, both wild-type (WT) and Ninj1 knockout (KO), that were treated with azoxymethane (AOM) and dextran sulfate sodium (DSS), were sacrificed at week 2 and 13 after AOM injection, with or without additional treatment of 17β-estradiol (E2) or testosterone propionate (TP). Clinical symptoms, histological severity of colitis, the levels of inflammatory mediators, and tumor number in the colon from the mice were evaluated.

Results

In male mice, the scores of disease activity index (DAI) and colonic epithelial damage and the ELISA levels of IL-6 and IL-1β increased by AOM/DSS treatment were significantly decreased by E2 treatment in WT group (Table). Compared to WT, the scores and the ELISA levels increased by AOM/DSS treatment were lower in the Ninj1 KO group, and the inhibitory effect of E2 was also attenuated in the Ninj1 KO group. Interestingly, a large tumor number exceeding 2 mm in size generated from a distal colon was also significantly lower in the Ninj1 KO group than in the WT group, and the inhibitory effect of E2 was also attenuated in Ninj1 KO group (Table). In female mice, DAI and damage scores increased by AOM/DSS treatment were lower in Ninj1 KO group than in WTs (Table). However, the effect of TP supplementation only showed a tendency to increase scores in both the WT and Ninj1 KO groups. In female mice, there was no difference in the larger tumor number generated by AOM/DSS treatment between WT and Ninj1 KO, but the tumor promoting effect of TP was significantly increased in the Ninj1 KO group (Table). Interestingly, the tumor-promoting effect of TP showed a significant increase in the KO group than in the WT in proximal colon in female mice.

Table. Summary of occurrence tumors by colon location.

Conclusion

In terms of inflammation or tumor development, the effect of Ninj1 KO was stronger in males than in females. In particular, the suppressive effect of E2 was weakened in the Ninj1 KO group, while the promoting effect of TP was strengthened in the Ninj1 KO group. Taken together Ninj1 look like to promote colorectal tumorigenesis in in males, which was opposite to that of estrogen. Investigation of its underlying mechanism of Ninj1 is undergoing by molecular experiments.
Funding: This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT).(2019R1A2C2085149).

Introduction

Colorectal carcinogenesis is intricately associated with dynamic interactions between gut microbiota and immune microenvironment remodeling(1). While microbial colonization within tumors creates complex pathophysiological conditions, emerging evidence paradoxically indicates suppressed tumor proliferation in bacteria-rich regions compared to microbe-deficient areas(2), suggesting indirect oncogenic mechanisms. This study investigates the immunomodulatory axis of microbiota-CRC interactions, particularly focusing on bacterial translocation-triggered immune reprogramming. Our previous findings showed that gallic acid ameliorates colitis through barrier enhancement and bacterial containment, we now extended it to CRC models to delineate how microbial translocation modulates tumor-associated immune landscapes.

Aims & Methods

1) To elucidate the effect of interaction between immune cells and gut bacteria in CRC progression and the potential mechanism;
2) find novel therapeutic targets at the microbiota-immunity interface for precision CRC intervention.
We used AOM/DSS and APCmin/+model to evaluate the effect of Gallic acid on colonic carcinogenesis. Single cell sequencing was used to deep investigate the effect of bacteria translocation on immune landscape. Conditional gene edited animals were used for mechanistic study.

Results

GA suppresses CRC progression by reinforcing barrier function and reducing microbial translocation. Mechanistically, bacterial invasion drives neutrophil infiltration, whose-derived reactive oxygen species (ROS) promote tumor oxidative stress and establish an immunosuppressive niche (elevated Tregs, reduced and impaired CD8+T cells). Further investigations identified tumor necrosis factor receptor 2 (TNFR2) as a pivotal regulator of this process: TNFR2 supports Treg expansion under oxidative stress but exacerbates CD8+ T cell dysfunction. Genetic ablation of TNFR2 in Tregs or CD8+ T cells attenuates CRC progression, and therapeutic targeting of TNFR2 with neutralizing antibodies achieves comparable efficacy.

Conclusion

Our study establishes a “gut microbiota-neutrophil-TNFR2” immunosuppressive axis that promotes CRC development.

References

(1) C. C. Wong, J. Yu, Gut microbiota in colorectal cancer development and therapy. Nat Rev Clin Oncol, (2023).
(2) J. L. Galeano Nino et al., Effect of the intratumoral microbiota on spatial and cellular heterogeneity in cancer. Nature 611, 810-817 (2022).

Introduction

Angiogenesis is a hallmark of cancer¹ and it plays a critical role in tumor development, especially in the proliferation and progression of colorectal cancer (CRC)^2,3.
Indeed, tumor vasculature prompts tumor growth and metastasis since it not only provides nutrients and oxygen for the rapid proliferation of cancer cells as well as a route for metastatization, but also affects the infiltration of immune cells to the tumor site. Thus, the targeting of angiogenesis has become an attractive strategy against various human malignancies, including CRC⁴_. In fact, tumor-associated vessels are leaky and poorly efficient due to the dismantlement of the basement membrane and the loss of pericytes, thus preventing proficient drug delivery to the tumor⁵_.
In this context, we demonstrated that Multimerin-2, an extracellular matrix glycoprotein deposited along the blood vessels in juxtaposition between endothelial cells and pericytes, mural cells fundamental in vessels stabilization, is key in the maintenance of vascular homoeostasis⁶_. However, the effects of this molecule on pericytes biology and its putative impact on the immune cells’ recruitment are still poorly understood.

Aims & Methods

Immunohistochemistry analysis on colorectal cancer patients’ biopsies revealed that colon cancer associated vessels display a downregulated expression of Multimerin-2. Thus, we aimed to verify the extent of pericyte recruitment by Multimerin-2-devoid vessels in a colon cancer model and to evaluate how Multimerin-2 loss affects the surrounding tumor microenvironment.
Human umbilical vein endothelial cells (HUVEC) and Human brain vascular pericytes (HBVP) were used as in vitro models for proliferation, functional assays, transcriptomic and proteomics analyses. Wild type and Multimerin-2^-/-C57BL/6 mice were subcutaneously injected with the syngeneic colon cancer MC-38 cells and the tumor sections were analysed by immunofluorescence analyses. Animals were then treated with cisplatin six hours prior sacrificing to evaluate the drug delivery.

Results

We demonstrated that Multimerin-2 affects pericytes migration, adhesion, and proliferation. MC-38 xenografts from Multimerin-2^-/-mice displayed lower number of pericytes along the vessels as well as increased hypoxia, likely due to vascular inefficiency. The delivery of drug to the tumors was impaired as assessed by the analysis of cisplatin DNA adducts, following the treatment with the chemotherapy drug.
Importantly, tumors from Multimerin-2^-/-mice also displayed an altered CD68⁺ cells infiltrate, suggesting that Multimerin-2 loss can affect macrophages recruitment to the tumor site. These results are in agreement with the finding that Multimerin-2 devoid endothelium was more permissive for the migration of the monocytic cell line THP-1. Finally, the loss of Multimerin-2 also associates with the expression of cytokines involved in macrophages recruitment.

Conclusion

In conclusion, loss of Multimerin-2 in CRC associates with poor pericyte recruitment, compromised delivery of drugs to the tumor, and an altered immune response. Our results suggest that Multimerin-2 expression could represent a promising marker to predict the efficacy of immunotherapy and the outcome of CRC patients.

References

1. Hanahan, D. & Weinberg, R. A. Hallmarks of Cancer: The Next Generation. Cell 144, 646–674 (2011).
2. Weis, S. M. & Cheresh, D. A. Tumor angiogenesis: molecular pathways and therapeutic targets. Nat Med 17, 1359–1370 (2011).
3. Angiogenesis Factors Involved in the Pathogenesis of Colorectal Cancer. Current Health Sciences Journal 5–11 (2013).
4. Rivera, L. B. & Bergers, G. Tumor angiogenesis, from foe to friend. Science 349, 694–695 (2015).
5. Carmeliet, P. & Jain, R. K. Principles and mechanisms of vessel normalization for cancer and other angiogenic diseases. Nat Rev Drug Discov 10, 417–427 (2011).
6. Pellicani, R. et al. Multimerin-2 maintains vascular stability and permeability. Matrix Biology 87, 11–25 (2020).

Introduction

Colorectal cancer remains a significant public health concern, with its incidence steadily rising worldwide. Despite notable strides in treatment modalities, predicting disease progression and tailoring therapeutic approaches remains a challenge. In this context, identifying reliable and simple prognostic factors is crucial for optimizing disease outcomes.

Aims & Methods

The aim of this study was to investigate the predictive and prognostic value of platelet-to-lymphocyte ratio (PLR). We conducted a retrospective and descriptive study including patients diagnosed with primary colon or rectal cancer, over an 8-year period [January 2014-June 2022]. Patient demographics, inflammatory markers, tumor characteristics, treatment and follow-up data were collected. Baseline PLR was calculated for each patient. Data were entered and analyzed by SPSS software version 26.

Results

Eighty-four patients were included, with a mean age at disease diagnosis of 60 ± 12 years and a sex ratio M/F=1.89. The median level of PLR was 169.80 [123.1-269.06]. Smoker patient have significantly higher PLR (p=0.01) as well as for patients with older age at diagnosis (Pearson p=0.001, r=0.35). No significant association was noted of PLR neither with family history of colorectal cancer (p= 0.47), nor gender (p=0.69), nor tumor localization (p=0.15). For biological data, anemia and hypoalbuminemia were significantly associated with a higher level of PLR (p=0.01 and p=0.001 respectively). Regarding treatment, neither primary surgery, nor adjuvant chemotherapy were associated with PLR (p=0.36 and p= 0.97 respectively). However, increased PLR was significantly associated with overall survival (p=0.001). Area under the receiver operating characteristic curve analysis showed that higher PLR was predictive of a shorter progression-free survival (AUROC = 0.706). The optimal cutoff value was 163.12 (sensitivity, 80%; specificity, 59%). A total of 48 (57%) patients had a PLR above this threshold. These patients presented more frequently with bowel obstruction (23% vs 6%, p=0.03). They also had a higher carcinoembryonic antigen rates (p=0.007). Advanced TNM stage 3 or 4 was more common in patients with PLR above this threshold and thus, neoadjuvant chemotherapy was more indicated in this group (29% vs 11%; p=0.04). Overall, disease recurrence was similar for PLR above and below 163.12 (p=0.12).

Conclusion

Our study demonstrated that PLR has a good predictive value of progression-free survival connected with clinicopathological parameters in patients with colorectal cancer. It is a valuable tool for a simple prognostic assessment during colorectal cancer, contributing to a more personalized treatment decisions.

Introduction

Segmental colitis associated with diverticulosis (SCAD) is an increasingly recognized clinical and pathological disorder, characterized by a chronic inflammatory response involving the inter-diverticular mucosa of a colonic segment, sparing the rectum and the right colon. However, its prevalence and outcome in the setting of colorectal cancer (CRC) screening is unknown.

Aims & Methods

Aims: to assess the prevalence of SCAD in the setting of a CRC screening program and to evaluate the differences in terms of oncological outcomes between SCAD and "simple" diverticulosis. We performed a retrospective analysis from a prospectively-maintained database including all subjects undergoing first screening colonoscopy according to regional CRC program from 2019 to 2022. Patients with incomplete colonoscopy, inadequate bowel preparation or known diagnosis of SCAD or CRC were excluded. Endoscopic signs of SCAD were registered as “crescentic fold disease”, “mild-to-moderate UC-like”, “Crohn’s disease-like” and “Severe UC-like”. The number of adenomas (ADR) and cancers was also recorded. Statistical analysis included chi-square, Student’s t-test and odds ratio (OR) with 95% confidence interval (CI) when indicated.

Results

a total of 1518 patients were included (males 51.8%, mean age 63.48±6.39). Adenomas were detected in 638 patients (ADR 42%), while CRC was diagnosed in 86 cases (5.7%). Diverticulosis was described in 570/1518 patients (37.5%), while SCAD was endoscopically diagnosed in 69 patients (4.5%). Among them, 48 (69.6%) presented a crescentic fold disease, 14 (20.3%) a mild-to-moderate UC-like pattern, 6 (8.7%) a CD-like pattern and 1 (1.4%) had a severe UC-like pattern. When SCAD patients were compared to subjects with simple diverticulosis (501 patients), we found no differences in terms of gender (males 55.1% vs 50.7%, p=0.46) or age (63.86±6.45 vs 64.45±6.38, p=0.47). Interestingly, the use of anticoagulant/antiplatelet (28.9% vs 30.1%, p=0.79), anti-hypertensive (46.4% vs 48.1%, p=0.89) or anti-hyperglycemic drugs (36.2% vs 41.1%, p=0.52) had no effect on SCAD onset as compared with patients with diverticulosis. However, patients with SCAD had significant lower rate of adenomas (ADR 31.9% vs 47.3%, p=0.018, OR 0.52, 95%CI 0.31-0.89), and lower –but not significant– rate of CRC (1.4% vs 6.2%, p=0.14, OR 0.22, 95%CI 0.02-1.66). Most patients were successfully treated with 5-ASA and none needed surgery for SCAD.

Conclusion

SCAD can be diagnosed in about 5% of population undergoing screening colonoscopy and in about 12% of those with diverticulosis. SCAD seems to be associated with a reduced rate of adenomas or CRC as compared with diverticulosis.