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Five-year overall survival of stage III colorectal cancer (CRC) patients treated with standard adjuvant chemotherapy (ACHT) is highly variable. Genomic biomarkers and/or transcriptomic profiles identified lack of adequate validation. Aim of our study was to identify and validate molecular biomarkers predictive of ACHT response in stage III CRC patients by a transcriptomic approach. From a series of CRC patients who received ACHT, two stage III extreme cohorts (unfavorable vs. favorable prognosis) were selected. RNA-sequencing was performed from fresh frozen explants. Tumors were characterized for somatic mutations. Validation was performed in stage III CRC patients extracted from two GEO datasets. According to disease-free survival (DFS), 108 differentially expressed genes (104/4 up/downregulated in the unfavorable prognosis group) were identified. Among 104 upregulated genes, 42 belonged to olfactory signaling pathways, 62 were classified as pseudogenes (n = 17), uncharacterized noncoding RNA (n = 10), immune response genes (n = 4), microRNA (n = 1), cancer-related genes (n = 14) and cancer-unrelated genes (n = 16). Three out of four down-regulated genes were cancer-related. Mutational status (i.e., RAS, BRAF, PIK3CA) did not differ among the cohorts. In the validation cohort, multivariate analysis showed high PNN and KCNQ1OT1 expression predictive of shorter DFS in ACHT treated patients (p = 0.018 and p = 0.014, respectively); no difference was observed in untreated patients. This is the first study that identifies by a transcriptomic approach and validates PNN and KCNQ1OT1 as molecular biomarkers predictive of chemotherapy response in stage III CRC patients. After a further validation in an independent cohort, PNN and KCNQ1OT1 evaluation could be proposed to prospectively identify stage III CRC patients benefiting from ACHT.

Systemic sclerosis (SSc) is a complex connective tissue disease characterized by fibrosis of the skin and various internal organs. In SSc, telocytes, a peculiar type of stromal (interstitial) cells, display severe ultrastructural damages and are progressively lost from the clinically affected skin. The aim of the present work was to investigate the presence and distribution of telocytes in the internal organs of SSc patients. Archival paraffin-embedded samples of gastric wall, myocardium and lung from SSc patients and controls were collected. Tissue sections were stained with Masson's trichrome to detect fibrosis. Telocytes were studied on tissue sections subjected to CD34 immunostaining. CD34/CD31 double immunofluorescence was performed to unequivocally differentiate telocytes (CD34-positive/CD31-negative) from vascular endothelial cells (CD34-positive/CD31-positive). Few telocytes entrapped in the fibrotic extracellular matrix were found in the muscularis mucosae and submucosa of SSc gastric wall. In the muscle layers and myenteric plexus, the network of telocytes was discontinuous or even completely absent around smooth muscle cells and ganglia. Telocytes were almost completely absent in fibrotic areas of SSc myocardium. In SSc fibrotic lung, few or no telocytes were observed in the thickened alveolar septa, around blood vessels and in the interstitial space surrounding terminal and respiratory bronchioles. In SSc, the loss of telocytes is not restricted to the skin, but it is a widespread process affecting multiple organs targeted by the fibrotic process. As telocytes are believed to be key players in the regulation of tissue/organ homoeostasis, our data suggest that telocyte loss might have important pathophysiological implications in SSc.

Crohn’s disease (CD) is a relapsing chronic inflammatory disorder that may involve all the gastrointestinal tract with a prevalence of terminal ileum. Intestinal lesions have a characteristic discontinuous and segmental distribution and may affect all layers of the gut wall. Telocytes (TC), a peculiar type of stromal cells, have been recently identified in a variety of tissues and organs, including gastrointestinal tract of humans and mammals. Several roles have been proposed for TC, including mechanical support, spatial relationships with different cell types, intercellular signalling and modulation of intestinal motility. The aim of our study was to investigate the presence and distribution of TC in disease-affected and -unaffected ileal specimens from CD patients compared with controls. TC were identified by CD34/PDGFRα immunohistochemistry. In affected CD specimens TC disappeared, particularly where fibrosis and architectural derangement of the intestinal wall were observed. In the thickened muscularis mucosae and submucosa, few TC entrapped in the fibrotic extracellular matrix were found. A discontinuous network of TC was present around smooth muscle bundles, ganglia and enteric strands in the altered muscularis propria. At the myenteric plexus, the loss of TC network was paralleled by the loss of interstitial cells of Cajal network. In the unaffected CD specimens, TC were preserved in their distribution. Our results suggest that in CD the loss of TC might have important pathophysiological implications contributing to the architectural derangement of the intestinal wall and gut dysmotility. Further functional studies are necessary to better clarify the role of TC loss in CD pathophysiology.

Aim The expression of pro-apoptotic (Bax) and anti-apoptotic (mutated p53, Bcl-2, Bclxl) proteins was determined retrospectively using immunohistochemistry in pre-treatment biopsy samples from patients with rectal cancer treated with or without preoperative chemoradiation to investigate their role as prognostic markers and indicators of radiochemosensitivity. Method Biopsy samples from 67 patients operated for stage II/III rectal cancer and enrolled in an active follow-up programme were examined 8–10 years after surgery. Thirty-three had been treated with immediate surgery followed, in selected cases, by adjuvant postoperative chemoradiation. Thirty-four had preoperative chemoradiation. Immunohistochemical staining was carried out using an automated immunostainer on sections of paraffin-embedded tissue. Results Independent prognostic factors for rectal cancer death were pN status (hazard ratio 3.82; 95% CI 1.67–8.73) and a high level of Bclxl positivity (hazard ratio 4.75; 95% CI 2.10–10.72) according to multivariate regression analysis by stepwise selection. Bax expression was associated with downstaging and higher survival in irradiated patients (P = 0.0004). Conclusion Pretreatment evaluation of apoptotic Bax and anti-apoptotic Bclxl factors in biopsy samples of stage II/III rectal cancers may be helpful in selecting tumours that will respond to chemoradiation or in identifying patients who will have limited benefit from chemoradiation and should therefore be selected for a more aggressive systemic regimen.

Objective Although gastrointestinal tract dysfunction is a common feature in patients with systemic sclerosis (SSc; scleroderma), few studies have addressed the pathogenetic mechanisms of gastrointestinal tract involvement in SSc. We previously showed that severe fibrosis and increased expression of profibrotic cytokines are important hallmarks in the gastric wall of patients with SSc. The aim of the present study was to investigate whether immune and/or microvascular abnormalities may account for tissue damage in gastric wall specimens obtained from patients with SSc. Methods Gastric biopsy samples from 27 patients with SSc and 15 healthy control subjects were analyzed by immunohistochemistry for CD45/leukocyte common antigen, CD3/T cells, CD4/T helper cells, CD8/cytotoxic T cells, CD20/B cells, CD14/monocytes, CD68/macrophages, cell adhesion molecules CD11a/lymphocyte function−associated antigen 1 (LFA-1), CD49d/very late activation antigen 4 (VLA-4), CD54/intercellular adhesion molecule 1 (ICAM-1), CD106/vascular cell adhesion molecule 1 (VCAM-1), CD31/platelet endothelial cell adhesion molecule 1, and vascular endothelial growth factor (VEGF). Results T cell infiltration was a prominent finding in gastric specimens from patients with SSc. The CD4+/CD8+ T cell ratio was significantly increased in SSc specimens compared with controls. T cells were found in both lymphocyte aggregates and diffuse infiltrates and strongly expressed the activation markers VLA-4, LFA-1, and ICAM-1. Endothelial cells showed corresponding surface activation with strong expression of VCAM-1 and ICAM-1. Mature B cells were frequently observed arranged in aggregates and rarely were seen in a diffuse pattern. Most lymphocyte aggregates lacked monocyte/macrophages. No difference in microvascular density was observed between SSc specimens and controls. Both SSc and control specimens showed weak or no expression of VEGF. Conclusion Our findings provide the first evidence that endothelial/lymphocyte activation leading to prominent CD4+ T cell infiltration may play a key pathogenetic role within the gastric wall of patients with SSc and may represent an important therapeutic target.

Rats transgenic for HLA-B27 and human beta2microglobulin (B27TR) develop a multi-systemic disease resembling inflammatory bowel disease (IBD) and spondyloarthritis. TNFalpha has a crucial role in chronic inflammation. Our objective was to evaluate the effect of anti-TNFalpha treatment on spontaneous IBD in B27TR. Nine-week-old B27TR received monoclonal anti-TNFalpha or an isotypic IgG2a,k up to age of 18 weeks. A second group was monitored up to 18 weeks and then randomly assigned to anti-TNFalpha or IgG2 a,k treatment. Each rat was monitored for clinical IBD manifestations. After sacrifice, the colon was examined for pathological changes. TNFalpha receptors (TNF-R1, TNF-R2), Fas/Fas-L expression and apoptosis were evaluated. IgG2a,k-treated and untreated B27TR presented signs of IBD at 11 weeks, whereas in anti-TNFalpha-treated B27TR no IBD signs were detected. In the late treatment, IBD signs improved after 1 week. Histopathological analysis of IgG2a,k-treated B27TR colon showed inflammatory signs that were widely prevented by early anti-TNFalpha treatment. Late treatment did not significantly reduce inflammation. TNF-R1 was weakly expressed in intestinal epithelial cells of IgG2a,k-treated B27TR, while it was comparable to controls in anti-TNFalpha-treated animals. TNF-R2 immunopositivity was strongly evident in IgG2a,k-treated B27TR, whereas was absent in anti-TNFalpha-treated rats. RT-PCR confirmed these results. IgG2a,k-treated B27TR showed, at 18 weeks, few Fas-positive cells and an increase of Fas-L-positive cells. At 27 weeks, Fas-/Fas-L-positive cell number was significantly low. Anti-TNFalpha treatment increased Fas-L expression, whereas Fas increased only with the early treatment. TNFalpha blockade is effective in preventing inflammation in early phase of IBD, maintaining the homeostatic balance of apoptosis.

Background and Objectives: Ileorectal anastomosis (IRA) is still used in the treatment of familial adenomatous polyposis (FAP). Sulindac appears to induce regression of colorectal adenomas; however, its effects in long-term therapy and in preventing carcinoma remain unclear. Methods: Fifteen FAP patients treated by IRA received sulindac (200 mg/day) for a mean period of 48.6 ± 28.7 (range 12-124) months. Number, size, and type of rectal polyps were assessed by endoscopic and histological evaluation every 6 months. Results: Significant regression of polyps was observed in all patients after 6 months (P < 0.02). However, after a mean of 48.6 ± 28.7 months, both number and size of polyps increased again, showing no statistical difference with baseline values. Minute polyps appeared reddish, while the largest lesions were flat or slightly elevated. Endoscopic polypectomy was necessary in 9 patients and transanal surgical excision in 3. Two patients were submitted to restorative proctectomy because of a large polyp with severe dysplasia and a rectal cancer, respectively. Conclusions: Sulindac appears to influence the morphological appearence of polyps in FAP patients, inducing apparent regression. However, at a dose of 200 mg, it does not influence the progression of polyps toward a malignant pattern.