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Abstract Background Cancer-associated fibroblasts (CAFs), the primary component of tumor stroma in tumor microenvironments, are well-known contributors to the malignant progression of gallbladder cancer (GBC). Thrombospondins (THBSs or TSPs) comprise a family of five adhesive glycoproteins that are overexpressed in many types of cancers. However, the expression and potential roles of TSPs in the crosstalk between CAFs and GBC cells has remained unclear. Methods Peritumoral fibroblasts (PTFs) and CAFs were extracted from GBC tissues. Thrombospondin expression in GBC was screened by RT-qPCR. MTT viability assay, colony formation, EdU incorporation assay, flow cytometry analysis, Transwell assay, tumorsphere formation and western blot assays were performed to investigate the effects of CAF-derived TSP-4 on GBC cell proliferation, EMT and cancer stem-like features. Subcutaneous tumor formation models were established by co-implanting CAFs and GBC cells or GBC cells overexpressing heat shock factor 1 (HSF1) to evaluate the roles of TSP-4 and HSF1 in vivo. To characterize the mechanism by which TSP-4 is involved in the crosstalk between CAFs and GBC cells, the levels of a variety of signaling molecules were detected by coimmunoprecipitation, immunofluorescence staining, and ELISA assays. Results In the present study, we showed that TSP-4, as the stromal glycoprotein, is highly expressed in CAFs from GBC and that CAF-derived TSP-4 induces the proliferation, EMT and cancer stem-like features of GBC cells. Mechanistically, CAF-secreted TSP-4 binds to the transmembrane receptor integrin α2 on GBC cells to induce the phosphorylation of HSF1 at S326 and maintain the malignant phenotypes of GBC cells. Moreover, the TSP-4/integrin α2 axis-induced phosphorylation of HSF1 at S326 is mediated by Akt activation (p-Akt at S473) in GBC cells. In addition, activated HSF1 signaling increased the expression and paracrine signaling of TGF-β1 to induce the transdifferentiation of PTFs into CAFs, leading to their recruitment into GBC and increased TSP-4 expression in CAFs, thereby forming a positive feedback loop to drive the malignant progression of GBC. Conclusions Our data indicate that a complex TSP-4/integrin α2/HSF1/TGF-β cascade mediates reciprocal interactions between GBC cells and CAFs, providing a promising therapeutic target for gallbladder cancer patients.

Abstract Background Association of immune-related adverse events with tumor response has been reported. Reactive cutaneous capillary endothelial proliferation (RCCEP) is the most common adverse event related to camrelizumab, an immune checkpoint inhibitor, but lack of comprehensive analyses. In this study, we conducted comprehensive analyses on RCCEP in advanced hepatocellular carcinoma (HCC) patients treated with camrelizumab monotherapy. Methods Data were derived from a Chinese nationwide, multicenter phase 2 trial of camrelizumab in pre-treated advanced HCC. The occurrence, clinicopathological characteristics, and prognostic value of RCCEP were analyzed. Results With a median follow-up of 12.5 months, 145 of the 217 camrelizumab-treated patients (66.8%) experienced RCCEP (all grade 1 or 2). RCCEP occurred on the skin surface, mainly on the skin surface of head, face, and trunk. RCCEP could be divided into 5 types including “red-nevus-like,” “pearl-like,” “mulberry-like,” “patch-like,” and “tumor-like,” according to the morphological features. RCCEP biopsy and pathology showed capillary endothelial hyperplasia and capillary hyperplasia in dermis. Significant association between RCCEP occurrence with higher objective response rate was observed (19.3% vs. 5.6%; one-sided p = 0.0044). Compared with those without RCCEP, patients with RCCEP had prolonged progression-free survival (median PFS; 3.2 months vs. 1.9 months; one-sided p < 0.0001) and overall survival (median OS; 17.0 months vs. 5.8 months; one-sided p < 0.0001). In multivariable analyses, the development of RCCEP was significantly associated with prolonged PFS and OS after adjusting for baseline covariates. In addition, the landmark analyses of PFS and OS were consistent with the unadjusted analysis. Conclusions RCCEP occurred on the skin surface and was an immune response of skin capillary endothelial cells. RCCEP occurrence positively associated with outcomes of camrelizumab in advanced HCC.

Abstract The lungs are the second most common site of metastasis for colorectal cancer (CRC) after the liver. Rectal cancer is associated with a higher incidence of lung metastases compared to colon cancer. In China, the proportion of rectal cancer cases is around 50%, much higher than that in Western countries (nearly 30%). However, there is no available consensus or guideline focusing on CRC with lung metastases. We conducted an extensive discussion and reached a consensus of management for lung metastases in CRC based on current research reports and the experts’ clinical experiences and knowledge. This consensus provided detailed approaches of diagnosis and differential diagnosis and provided general guidelines for multidisciplinary therapy (MDT) of lung metastases. We also focused on recommendations of MDT management of synchronous lung metastases and initial metachronous lung metastases. This consensus might improve clinical practice of CRC with lung metastases in China and will encourage oncologists to conduct more clinical trials to obtain high-level evidences about managing lung metastases.

Abstract Background Estrogen promotes breast cancer development and progression mainly through estrogen receptor (ER). However, blockage of estrogen production or action prevents development of and suppresses progression of ER-negative breast cancers. How estrogen promotes ER-negative breast cancer development and progression is poorly understood. We previously discovered that deletion of cell cycle inhibitors p16Ink4a (p16) or p18Ink4c (p18) is required for development of Brca1-deficient basal-like mammary tumors, and that mice lacking p18 develop luminal-type mammary tumors. Methods A genetic model system with three mouse strains, one that develops ER-positive mammary tumors (p18 single deletion) and the others that develop ER-negative tumors (p16;Brca1 and p18;Brca1 compound deletion), human BRCA1 mutant breast cancer patient-derived xenografts, and human BRCA1-deficient and BRCA1-proficient breast cancer cells were used to determine the role of estrogen in activating epithelial-mesenchymal transition (EMT), stimulating cell proliferation, and promoting ER-negative mammary tumor initiation and metastasis. Results Estrogen stimulated the proliferation and tumor-initiating potential of both ER-positive Brca1-proficient and ER-negative Brca1-deficient tumor cells. Estrogen activated EMT in a subset of Brca1-deficient mammary tumor cells that maintained epithelial features, and enhanced the number of cancer stem cells, promoting tumor progression and metastasis. Estrogen activated EMT independent of ER in Brca1-deficient, but not Brca1-proficient, tumor cells. Estrogen activated the AKT pathway in BRCA1-deficient tumor cells independent of ER, and pharmaceutical inhibition of AKT activity suppressed EMT and cell proliferation preventing BRCA1 deficient tumor progression. Conclusions This study reveals for the first time that estrogen promotes BRCA1-deficient tumor initiation and progression by stimulation of cell proliferation and activation of EMT, which are dependent on AKT activation and independent of ER.

Abstract Background Among colorectal cancer (CRC) survivors, how the prior tumor location affects the risk of subsequent primary colorectal cancer (SPCRC) and the outcome of those suffering from SPCRC remain unknown. Methods CRC cases diagnosed from 1973 to 2012 were screened for SPCRC development using the Surveillance, Epidemiology, and End Results database. The relative risk of SPCRC was estimated using the standardized incidence ratio. Survivals were analyzed using the Kaplan–Meier and Cox regression model. Results The overall risk of SPCRC increased by 27% in CRC survivors compared to that of the general population. The risk increased in patients with both prior right colon cancer (RCC) and left colon cancer (LCC), and was concentrated in the first 5 years after the prior diagnosis, and among young patients. Among the 6701 SPCRC patients identified, patients with prior RCC were more likely to be elderly, female, and with more low or undifferentiated disease than those with prior LCC or rectal cancer (ReC). The overall survivals differed by both prior tumor location (P