Human cancer cells operate a variety of effective molecular and signaling mechanisms which allow them to escape host immune surveillance and thus progress the disease. We have recently reported that the immune receptor Tim-3 and its natural ligand galectin-9 are involved in the immune escape of human acute myeloid leukemia (AML) cells. These cells use the neuronal receptor latrophilin 1 (LPHN1) and its ligand fibronectin leucine rich transmembrane protein 3 (FLRT3, and possibly other ligands) to trigger the pathway. We hypothesized that the Tim-3-galectin-9 pathway may be involved in the immune escape of cancer cells of different origins. We found that studied breast tumors expressed significantly higher levels of both galectin-9 and Tim-3 compared to healthy breast tissues of the same patients and that these proteins were co-localized. Increased levels of LPHN2 and expressions of LPHN3 as well as FLRT3 were also detected in breast tumor cells. Activation of this pathway facilitated the translocation of galectin-9 onto the tumor cell surface, however no secretion of galectin-9 by tumor cells was observed. Surface-based galectin-9 was able to protect breast carcinoma cells against cytotoxic T cell-induced death. Furthermore, we found that cell lines from brain, colorectal, kidney, blood/mast cell, liver, prostate, lung, and skin cancers expressed detectable amounts of both Tim-3 and galectin-9 proteins. The majority of cell lines expressed one of the LPHN isoforms and FLRT3. We conclude that the Tim-3-galectin-9 pathway is operated by a wide range of human cancer cells and is possibly involved in prevention of anti-tumor immunity.

Between 1991 and 1993, 106 newly diagnosed cases of Hirschsprung's disease (HD) were prospectively analyzed for the association of HD and intestinal neuronal dysplasia (IND) at ten pediatric surgical departments in central Europe. Hirschsprung-associated IND (HaIND) was found in 40% of cases. IND was disseminated in one-third and localized in two-thirds of the patients. Initial clinical symptoms were related to the length of the aganglionic segment, but not to the presence of HaIND. An enterostomy performed in 72 cases (67.9%) was located in a segment of pathologically innervated bowel in 50% of all cases, but in 72% of cases of HaIND. The proximal margin of the resected bowel showed pathological innervation in 44% of cases. Supplemental biopsies from the intestine (apart from diagnostic suction biopsies and biopsies at the enterostomy site) led to the first identification or definition of length of associated IND in 17.9% of cases. Postoperatively, the presence of long-segment aganglionosis or associated IND implied a delay in the restoration or normal defecation. Persistent constipation was found in 40% of patients with associated disseminated IND at follow-up at 6 months, compared to 20.6% in patients with isolated HD. These children needed secondary interventions more often than patients with associated localized IND or isolated HD. HaIND thus has clinical implications for the postoperative course if IND is disseminated.

Lacking colonic mucosal innervation correlated with increased inflammatory immune cell status, microbial dysbiosis, and higher incidence of postoperative enterocolitis in HSCR patients. Mucosal nerve fibers might serve as a prognostic marker for enterocolitis development and offer new therapeutic intervention strategies.