Commensal fungi and their cell-wall ß-glucans direct differential responses in human intestinal epithelial cells.

Intestinal epithelial cells (IECs) are the first to encounter luminal antigens and play an active role in intestinal immune responses. We previously reported that ß-glucans, major fungal cell-wall glycans, induced chemokine secretion by IEC lines in a Dectin-1- and Syk-dependent manner. Here, we show that in contrast to ß-glucans, stimulation of IEC lines with Candida albicans and Saccharomyces cerevisiae did not induce secretion of any of the proinflammatory cytokines IL-8, CCL2, CXCL1, and GM-CSF. Commensal fungi and ß-glucans activated Syk and ERK in IEC lines. However, only ß-glucans activated p38, JNK, and the transcription factors NF-κB p65 and c-JUN, which were necessary for cytokine secretion. Furthermore, costimulation of IEC lines with ß-glucans and C. albicans yielded decreased cytokine secretion compared to stimulation with ß-glucans alone. Finally, ex vivo stimulation of human colonic mucosal explants with zymosan and C. albicans, leads to epithelial Syk and ERK phosphorylation, implying recognition of fungi and similar initial signaling pathways as in IEC lines. Lack of cytokine secretion in response to commensal fungi may reflect IECs' response to fungal glycans, other than ß-glucans, that contribute to mucosal tolerance. Skewed epithelial response to commensal fungi may impair homeostasis and contribute to intestinal inflammation.

Human intestinal epithelial cells can internalize luminal fungi via LC3-associated phagocytosis.

Background: Intestinal epithelial cells (IECs) are the first to encounter luminal microorganisms and actively participate in intestinal immunity. We reported that IECs express the ß-glucan receptor Dectin-1, and respond to commensal fungi and ß-glucans. In phagocytes, Dectin-1 mediates LC3-associated phagocytosis (LAP) utilizing autophagy components to process extracellular cargo. Dectin-1 can mediate phagocytosis of ß-glucan-containing particles by non-phagocytic cells. We aimed to determine whether human IECs phagocytose ß-glucan-containing fungal particles via LAP. Methods: Colonic (n=18) and ileal (n=4) organoids from individuals undergoing bowel resection were grown as monolayers. Fluorescent-dye conjugated zymosan (ß-glucan particle), heat-killed- and UV inactivated C. albicans were applied to differentiated organoids and to human IEC lines. Confocal microscopy was used for live imaging and immuno-fluorescence. Quantification of phagocytosis was carried out with a fluorescence plate-reader. Results: zymosan and C. albicans particles were phagocytosed by monolayers of human colonic and ileal organoids and IEC lines. LAP was identified by LC3 and Rubicon recruitment to phagosomes and lysosomal processing of internalized particles was demonstrated by co-localization with lysosomal dyes and LAMP2. Phagocytosis was significantly diminished by blockade of Dectin-1, actin polymerization and NAPDH oxidases. Conclusions: Our results show that human IECs sense luminal fungal particles and internalize them via LAP. This novel mechanism of luminal sampling suggests that IECs may contribute to the maintenance of mucosal tolerance towards commensal fungi.

Searching for the emotional roots of breast cancer: A cross-disciplinary analysis integrating psychology, Chinese medicine, and oncology biomarkers.

OBJECTIVE: We employed a multidisciplinary approach incorporating theoretical ideas, clinical experience, psychology, physiology, traditional Chinese medicine (CM), modern practice of CM, and oncology to explore the effect of patients' repression of negative emotions and traumatic events on breast cancer (BC) pathogenesis. METHODS: BC female patients, older than 18 years of age, with available pathology reports who were treated at Rabin Medical Center were recruited. All participants completed questionnaires regarding medical history, behavioral tendencies, negative emotions, trauma, symptoms, and pathology (from a CM perspective). Data on tumor characteristics were collected from the pathology reports. The associations were examined using hierarchical binary logistic regressions. RESULTS: A total of 155 BC patients were enrolled. The median age was 52 years, with a range of 26-79; 95% were mothers; 28% had estrogen receptor (ER)-negative BC, 52% had progesterone receptor (PR)-negative BC, 48% had human epidermal growth factor receptor 2-negative BC, and antigen Ki-67 ≥ 20% was reported for 52% of tumors. Statistically significant associations were found between the emotional markers (sense of motherhood failure, and lack of self-fulfillment), avoidance behavior, and physical symptoms that are related to emotional repression based on CM. Significant associations were also found between variables associated with physical symptoms of emotional repression, which involves the production and accumulation of non-substantial phlegm (i.e., "high-lipid Qi-like microscopic phlegm"), avoidance behavior which unconsciously uses "high-lipid Qi-like microscopic phlegm" in order to achieve emotional repression, and tumor parameters including tumor grade, PR status, and Ki-67. Patients with higher levels of "high-lipid Qi-like microscopic phlegm" were more likely to have tumors with worse prognosis (PR-negative, higher grade, and higher Ki-67). CONCLUSION: We demonstrated a relationship between emotional parameters, behavioral tendencies, CM parameters, and oncologic parameters in BC. Additional research is warranted to explore these associations and their relevance to clinical practice.

Timing to imaging and surgery after neoadjuvant therapy for breast cancer.

Neoadjuvant therapy (NAT) is increasingly used in breast cancer (BC), yet, the recommended time interval between NAT completion, preoperative imaging assessment, and breast surgery is not clearly defined. This single-center retrospective study investigated tumor growth between NAT completion and surgery. The analysis included 106 BC patients who received NAT (69% chemotherapy alone, 31% chemotherapy plus anti-HER2 therapy), had post-NAT breast MRI, and definitive surgery between 2012 and 2019. The median time interval between end-of-treatment and surgery was 6 weeks; 90% had surgery within 8 weeks of NAT completion, and 10% had surgery 8-12 weeks after NAT completion. No significant correlation was found between any of the time intervals (i.e., NAT completion-to-surgery, NAT completion-to-MRI, post-NAT MRI to surgery) and the tumor size as captured in the pathology report. The only parameter that was significantly correlated with pathological tumor size was tumor size as measured on the post NAT MRI (P < .0001). The difference in tumor size between post NAT MRI and surgical pathology did not correlate with the time interval between end-of-treatment and surgery. The ratio between residual tumor size on post-NAT MRI and the time interval from the end-of-treatment to surgery, significantly correlated with the tumor size on surgical pathology (P < .0001) suggesting that NAT has a beneficial effect weeks after end-of-treatment. In conclusion, our results suggest that for patients undergoing neoadjuvant chemotherapy, surgery within 4-8 weeks of completing NAT is reasonable, and is unlikely to result in a clinically significant change in residual tumor size.

An 8-Year-Old Child with Malignant Deciduoid Mesothelioma of the Abdomen: Report of a Case and Review of the Literature.

Malignant mesothelioma is an uncommon tumor that usually arises in the pleural cavity of adults with a history of asbestos exposure. Less frequently, it appears in the peritoneum or other mesothelial surfaces. Deciduoid mesothelioma is a rare subtype that has been found at both sites. Of the 3 reported cases in children, 2 originated in the mesenterium and 1 in the pleura. We describe a 4th case of pediatric, malignant, deciduoid mesothelioma and a third case in the mesenteric cavity. The patient was an 8-year-old girl who presented with abdominal pain and fullness. Workup revealed extensive involvement of the abdomen by a serosa-based tumor. The clinical and pathologic findings are described, and the pertinent literature is reviewed.