Abstract 150P
Background
Systemic and intratumoral inflammation in patients with Colorectal Carcinoma (CRC) has been directly linked to disease prognosis. Analyzing the interaction of interleukins, intratumoral lymphocytic infiltrates, tumor microenvironment, and microbiota is essential for understanding the pathogenesis and progression of the disease.
Methods
We conducted comprehensive analyses on 32 patients with CRC. Before treatment, we gathered primary tumor tissue and tissue samples from another site in the colon. Also, blood samples were collected before and after chemotherapy to analyze an inflammatory panel (IL-6, IL-10, IL-1,β CXCL-8, CASP-1, TLR2, DUSP-1, TNF-α). We obtained 15 fecal samples before treatment and 26 samples post-treatment to assess the diversity and abundance of microbiota.
Results
All 32 patients underwent chemotherapy. The median age was 49 years, 56% were female, 81.2% had left-sided CRC, and 71.9% presented with stage IV disease. Comparing tumor tissue versus non-tumor tissue samples, we noted a higher concentration of IL-6 (p 0.001) in the tumor. Post-chemotherapy, we observed a decrease in TNFα (p 0.04) in serum and a reduction in the expression of inflammatory genes IL-10 (p 0.005) and NRLP-1 (p 0.03) in peripheral blood cells. Notably, in the 11 paired pre- and post-treatment fecal samples, we found no changes in the diversity indices in the microbiome. The phylum Firmicutes remained the most abundant and were unaffected by systemic treatment. Interestingly, no lactobacillus species were detected in the fecal samples.
Conclusions
Interleukins and inflammatory genes are elevated in patients with CRC before systemic treatment. Inflammation is higher at the tumor site compared to healthy colonic tissue. Following chemotherapy, we found a decrease in interleukins and pro-inflammatory genes and discordant expression between plasma and peripheral blood cells. Interestingly, systemic treatment did not alter microbiome diversity in our patients. Understanding the interplay between inflammation and changes in microbiota could serve as a crucial foundation for future research endeavors.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.