Investigation of IL23 (p19, p40) and IL23R highlights nuclear IL23p19 expression as a marker of indolent tumor features and favorable outcome in colorectal cancer patients

Objective: IL23 is involved in chronic inflammation but its role in cancer progression is not fully elucidated. Here we characterize IL23 subunits p40, p19 and IL23 receptor (IL23R) in the normal-adenoma-carcinomametastasis cascade of colorectal cancers and their relationship to clinicopathological and outcome data. Method: Immunohistochemistry for IL23R, IL12p40, IL23 and IL23p19 (monoclonal) was performed on a multi-punch tissue microarray (n=213 patients). Expression differences between normal-adenomas-cancerslymph nodes were evaluated. Correlation with clinicopathological and outcome data was undertaken. Results were validated on an independent cohort (n=341 patients). Results: An increased expression from normal-adenoma-cancer was observed (p<0.0001; all) followed by a marked reduction in lymph nodes (p<0.0001; all). Cytoplasmic and/or membranous staining of all markers was unrelated to outcome. Nuclear IL23p19 staining occurred in 23.1%and was associated with smaller tumor diameter (p=0.0333), early pT (p=0.0213), early TNM (p=0.0186), absence of vascular (p=0.0124) and lymphatic invasion (p=0.01493) and favorable survival (univariate (p=0.014) and multivariable (p=0.0321) analysis). All IL23p19 positive patients were free of distant metastasis (p=0.0146). Survival and metastasis results could be validated in Cohort 2. Conclusion: The presence of nuclear IL23p19 is related to indolent tumor features and favorable outcome supporting a more ‘protective’ role of this protein in colorectal cancer progression

NHERF1 – New Modifier of Colorectal Cancer Progression

Colorectal cancer (CRC) develops from multiple progressive modifications of normal intestinal epithelium into adenocarcinoma. Loss of cell polarity has been implicated as an early event in this process, but the molecular players involved are not well known. NHERF1 (Na+/H+ Exchanger Regulatory Factor 1) is an adaptor protein with apical membrane localization in polarized epithelia. In this study, we tested our hypothesis that NHERF1 plays a role in CRC. We examined surgical CRC resection specimens for changes in NHERF1 expression, and modeled these changes in two- and three-dimensional (2D and 3D) Caco-2 CRC cell systems. NHERF1 had significant alterations from normal to adenoma and carcinoma transitions (2=38.5, d.f.=4, P<0.001), displaying apical membrane localization in normal tissue but loss of expression in adenoma and ectopic overexpression in carcinoma. In Caco-2 cell models, NHERF1 depletion induced epithelial-mesenchymal-transition in 2D cell monolayers and disruption of apical-basal polarity in 3D cyst system. The mesenchymal phenotype of NHERF1-depleted cells was fully restored by re-expression of NHERF1 at the apical membrane. Cytoplasmic and nuclear NHERF1 re-expression not only failed to restore the epithelial phenotype but led to more aggressive phenotypes. Our findings suggest that membrane NHERF1 is an important regulator of epithelial morphogenesis, and that changes in NHERF1 expression correlate with CRC progression. NHERF1 loss and ectopic expression that induce massive disruption of epithelial cell polarity may, thereby, mark important steps in CRC development.

Genetic variation in genes for the xenobiotic-metabolizing enzymes CYP1A1, EPHX1, GSTM1, GSTT1, and GSTP1 and susceptibility to colorectal cancer in Lynch syndrome.

Individuals with Lynch syndrome are predisposed to cancer due to an inherited DNA mismatch repair gene mutation. However, there is significant variability observed in disease expression likely due to the influence of other environmental, lifestyle, or genetic factors. Polymorphisms in genes encoding xenobiotic-metabolizing enzymes may modify cancer risk by influencing the metabolism and clearance of potential carcinogens from the body. In this retrospective analysis, we examined key candidate gene polymorphisms in CYP1A1, EPHX1, GSTT1, GSTM1, and GSTP1 as modifiers of age at onset of colorectal cancer among 257 individuals with Lynch syndrome. We found that subjects heterozygous for CYP1A1 I462V (c.1384A>G) developed colorectal cancer 4 years earlier than those with the homozygous wild-type genotype (median ages, 39 and 43 years, respectively; log-rank test P = 0.018). Furthermore, being heterozygous for the CYP1A1 polymorphisms, I462V and Msp1 (g.6235T>C), was associated with an increased risk for developing colorectal cancer [adjusted hazard ratio for AG relative to AA, 1.78; 95% confidence interval, 1.16-2.74; P = 0.008; hazard ratio for TC relative to TT, 1.53; 95% confidence interval, 1.06-2.22; P = 0.02]. Because homozygous variants for both CYP1A1 polymorphisms were rare, risk estimates were imprecise. None of the other gene polymorphisms examined were associated with an earlier onset age for colorectal cancer. Our results suggest that the I462V and Msp1 polymorphisms in CYP1A1 may be an additional susceptibility factor for disease expression in Lynch syndrome because they modify the age of colorectal cancer onset by up to 4 years.

Does colon cancer ever metastasize to bone first? a temporal analysis of colorectal cancer progression.

BACKGROUND: It is well recognized that colorectal cancer does not frequently metastasize to bone. The aim of this retrospective study was to establish whether colorectal cancer ever bypasses other organs and metastasizes directly to bone and whether the presence of lung lesions is superior to liver as a better predictor of the likelihood and timing of bone metastasis. METHODS: We performed a retrospective analysis on patients with a clinical diagnosis of colon cancer referred for staging using whole-body 18F-FDG PET and CT or PET/CT. We combined PET and CT reports from 252 individuals with information concerning patient history, other imaging modalities, and treatments to analyze disease progression. RESULTS: No patient had isolated osseous metastasis at the time of diagnosis, and none developed isolated bone metastasis without other organ involvement during our survey period. It took significantly longer for colorectal cancer patients to develop metastasis to the lungs (23.3 months) or to bone (21.2 months) than to the liver (9.8 months). Conclusion: Metastasis only to bone without other organ involvement in colorectal cancer patients is extremely rare, perhaps more rare than we previously thought. Our findings suggest that resistant metastasis to the lungs predicts potential disease progression to bone in the colorectal cancer population better than liver metastasis does.

CD8/CD45RO T-cell infiltration in endoscopic biopsies of colorectal cancer predicts nodal metastasis and survival

BACKGROUND AND AIMS: Reliable prognostic markers based on biopsy specimens of colorectal cancer (CRC) are currently missing. We hypothesize that assessment of T-cell infiltration in biopsies of CRC may predict patient survival and TNM-stage before surgery. METHODS: Pre-operative biopsies and matched resection specimens from 130 CRC patients treated from 2002-2011 were included in this study. Whole tissue sections of biopsy material and primary tumors were immunostained for pancytokeratin and CD8 or CD45RO. Stromal (s) and intraepithelial (i) T-cell infiltrates were analyzed for prediction of patient survival as well as clinical and pathological TNM-stage of the primary tumor. RESULTS: CD8 T-cell infiltration in the preoperative biopsy was significantly associated with favorable overall survival (CD8i p = 0.0026; CD8s p = 0.0053) in patients with primary CRC independently of TNM-stage and postoperative therapy (HR [CD8i] = 0.55 (95% CI: 0.36-0.82), p = 0.0038; HR [CD8s] = 0.72 (95% CI: 0.57-0.9), p = 0.0049). High numbers of CD8i in the biopsy predicted earlier pT-stage (p < 0.0001) as well as absence of nodal metastasis (p = 0.0015), tumor deposits (p = 0.0117), lymphatic (p = 0.008) and venous invasion (p = 0.0433) in the primary tumor. Infiltration by CD45ROs cells was independently associated with longer survival (HR = 0.76 (95% CI: 0.61-0.96), p = 0.0231) and predicted absence of venous invasion (p = 0.0025). CD8 counts were positively correlated between biopsies and the primary tumor (r = 0.42; p < 0.0001) and were reproducible between observers (ICC [CD8i] = 0.95, ICC [CD8s] = 0.75). For CD45RO, reproducibility was poor to moderate (ICC [CD45i] = 0.16, ICC [CD45s] = 0.49) and correlation with immune infiltration in the primary tumor was fair and non-significant (r[CD45s] = 0.16; p = 0.2864). For both markers, no significant relationship was observed with radiographic T-stage, N-stage or M-stage, indicating that assessment of T-cells in biopsy material can add additional information to clinical staging in the pre-operative setting. CONCLUSIONS: T-cell infiltration in pre-operative biopsy specimens of CRC is an independent favorable prognostic factor and strongly correlates with absence of nodal metastasis in the resection specimen. Quantification of CD8i is highly reproducible and allows superior prediction of clinicopathological features as compared to CD45RO. The assessment of CD8i infiltration in biopsies is recommended for prospective investigation.