Cancer-related inflammation and treatment effectiveness

Inflammaging and cancer: a challenge for the Mediterranean diet

Aging is considered the major risk factor for cancer, one of the most important mortality causes in the western world. Inflammaging, a state of chronic, low-level systemic inflammation, is a pervasive feature of human aging. Chronic inflammation increases cancer risk and affects all cancer stages, triggering the initial genetic mutation or epigenetic mechanism, promoting cancer initiation, progression and metastatic diffusion. Thus, inflammaging is a strong candidate to connect age and cancer. A corollary of this hypothesis is that interventions aiming to decrease inflammaging should protect against cancer, as well as most/all age-related diseases. Epidemiological data are concordant in suggesting that the Mediterranean Diet (MD) decreases the risk of a variety of cancers but the underpinning mechanism(s) is (are) still unclear. Here we review data indicating that the MD (as a whole diet or single bioactive nutrients typical of the MD) modulates multiple interconnected processes involved in carcinogenesis and inflammatory response such as free radical production, NF-κB activation and expression of inflammatory mediators, and the eicosanoids pathway. Particular attention is devoted to the capability of MD to affect the balance between pro- and anti-inflammaging as well as to emerging topics such as maintenance of gut microbiota (GM) homeostasis and epigenetic modulation of oncogenesis through specific microRNAs.

Cytokine profile and prognostic significance of high neutrophil-lymphocyte ratio in colorectal cancer

Background:

High circulating neutrophil-lymphocyte ratio (NLR) appears to be prognostic in metastatic colorectal cancer (mCRC). We investigated the relationship of NLR with circulating cytokines and molecular alterations.

Methods:

We performed retrospective analyses on multiple cohorts of CRC patients (metastatic untreated (n=166), refractory metastatic (n=161), hepatectomy (n=198), stage 2/3 (n=274), and molecularly screened (n=342)). High NLR (ratio of absolute neutrophil-to-lymphocyte counts in peripheral blood) was defined as NLR>5. Plasma cytokines were evaluated using multiplex-bead assays. Kaplan–Meier estimates, non-parametric correlation analysis, and hierarchical cluster analyses were used.

Results:

High NLR was associated with poor prognosis in mCRC (hazard ratio (HR) 1.73; 95% confidence interval (CI):1.03–2.89; P=0.039) independent of known prognostic factors and molecular alterations (KRAS/NRAS/BRAF/PIK3CA/CIMP). High NLR correlated with increased expression of interleukin 6 (IL-6), IL-8, IL-2Rα, hepatocyte growth factor, macrophage-colony stimulating factor, and vascular epidermal growth factor in exploratory (n=39) and validation (n=166) cohorts. Fourteen additional cytokines correlated with high NLR in the validation cohort. All 20 cytokines fell into three major clusters: inflammatory cytokines, angiogenic cytokines, and epidermal growth factor ligands. In mCRC, composite stratification based on NLR-cytokine score provided enhanced prognostic information (HR 2.09; 95% CI: 1.59–2.76; P<0.001) over and above NLR.

Conclusions:

High NLR is an independent poor prognostic marker in CRC and correlates with a distinct cytokine profile related to key biological processes involved in carcinogenesis. A composite NLR-cytokine stratification has enhanced prognostic value in mCRC.

Enhanced expression of suppresser of cytokine signaling 3 inhibits the IL-6-induced epithelial-to-mesenchymal transition and cholangiocarcinoma cell metastasis

It was recently demonstrated that interleukin-6 (IL-6) induces the epithelial-to-mesenchymal transition (EMT) in cholangiocarcinoma (CCA), but the underlying molecular mechanism remains to be explored. In this study, we studied the role of suppresser of cytokine signaling 3 (SOCS3), a negative feedback regulator of IL-6/STAT3, in the IL-6-induced EMT in CCA. Treatment with IL-6 induced the EMT by decreasing the E-cadherin expression and increasing the expression of N-cadherin and vimentin. Using wound healing and invasion assays, we found that IL-6 promoted cell motility. Further, a stably transfected cell line overexpressing SOCS3 was constructed. Enhanced SOCS3 expression decreased IL-6-induced cell invasion and EMT in parallel with downregulating the IL-6/STAT3 pathway. In contrast, SOCS3 silencing using siRNA exhibited no effect on the cell invasive ability and EMT. Finally, an in vivo study indicated that the enhancement of SOCS3 expression decreased metastasis compared with the control, and this effect was achieved by the repression of p-STAT3, N-cadherin and vimentin, and the induction of E-cadherin assessed by Western blot analysis. Our results suggest that enhanced expression of SOCS3 can antagonize IL-6-induced EMT and cell metastasis by abrogating the IL-6/STAT3 pathway. These data establish that SOCS3 plays a role in the EMT in CCA and may provide novel therapeutic strategies for CCA.