Periostin in Cancer-Associated Fibroblasts Promotes Esophageal Squamous Cell Carcinoma Progression by Enhancing Cancer and Stromal Cell Migration.

Cancer-associated fibroblasts (CAFs) in the tumor microenvironment are involved in the progression of various cancers, including esophageal squamous cell carcinoma (ESCC). CAF-like cells were generated through direct co-culture of human bone marrow-derived mesenchymal stem cells, one of CAF origins, with ESCC cells. Periostin (POSTN) was found to be highly expressed in CAF-like cells. After direct co-culture, ESCC cells showed increased malignant phenotypes, such as survival, growth, and migration, as well as increased phosphorylation of Akt and extracellular signal-regulated kinase (Erk). Recombinant human POSTN activated Akt and Erk signaling pathways in ESCC cells, enhancing survival and migration. The suppression of POSTN in CAF-like cells by siRNA during direct co-culture also suppressed enhanced survival and migration in ESCC cells. In ESCC cells, knockdown of POSTN receptor integrin ß4 inhibited Akt and Erk phosphorylation, and survival and migration increased by POSTN. POSTN also enhanced mesenchymal stem cell and macrophage migration and endowed macrophages with tumor-associated macrophage-like properties. Immunohistochemistry showed that high POSTN expression in the cancer stroma was significantly associated with tumor invasion depth, lymphatic and blood vessel invasion, higher pathologic stage, CAF marker expression, and infiltrating tumor-associated macrophage numbers. Moreover, patients with ESCC with high POSTN expression exhibited poor postoperative outcomes. Thus, CAF-secreted POSTN contributed to tumor microenvironment development. These results indicate that POSTN may be a novel therapeutic target for ESCC.

Association between tumor morphology and efficacy of atezolizumab plus bevacizumab for advanced hepatocellular carcinoma.

AIM: The IMbrave150 trial revealed that atezolizumab plus bevacizumab (AtezoBv) showed a higher objective response rate (ORR) in patients with advanced hepatocellular carcinoma (HCC). Although conversion therapy after AtezoBv has been recently reported, markers predictive of its efficacy, particularly radiological imaging markers, have not yet been identified. The present study focused on tumor morphological appearance on radiological imaging and evaluated whether it could be associated with AtezoBv efficacy. METHODS: Ninety-five intrahepatic lesions in 74 patients who were given AtezoBv for advanced HCC were recruited for evaluation. The lesions were divided into two groups, simple nodular (SN group) and non-simple nodular (non-SN group), based on the gross morphology on pretreatment imaging, and retrospectively evaluated for treatment response and other relevant clinical outcomes. RESULTS: Assessing the size of individual tumors after treatment, waterfall plots showed that tumor shrinkage in the non-SN group including 56 lesions was higher than that in the SN group comprising 39 lesions. The ORR was significantly higher in the non-SN group (39.3% vs. 15.4%, p = 0.012). Additionally, the median time to nodular progression was longer in the non-SN group (21.0 months vs. 8.1 months, p = 0.119) compared to the SN group. Six patients with non-SN lesions underwent sequential local therapy. CONCLUSIONS: Atezolizumab plus bevacizumab may show increased therapeutic efficacy in patients with tumors with a higher potential for aggressive oncological behavior, such as non-SN lesions. Treatment strategies focusing on conversion therapy may be crucial in patients with non-SN lesions.

Novel concept of "sequential particle radiotherapy" with atezolizumab plus bevacizumab for hepatocellular carcinoma with portal vein tumor thrombus.

Owing to the high objective response rate of atezolizumab plus bevacizumab (Atez/Bev) for hepatocellular carcinoma (HCC), the concept of sequential conversion to local treatment has recently become mainstream. The conversion concept is mainly applied to Barcelona Clinic for Liver Cancer (BCLC) stage B cases, and radiotherapy is rarely considered as a conversion local treatment. We herein report three patients who were treated with the novel concept of "sequential particle radiotherapy," consisting of Atez/Bev therapy followed by particle radiotherapy (PRT) for HCC with advanced portal vein tumor thrombus (Vp3/4 PVTT). All patients achieved partial response radiologically and were switched to PRT. All patients were recurrence free at 1 year after the introduction of Atez/Bev therapy without any additional treatment. This upcoming combination strategy includes the advocacy of sequential concepts for BCLC stage C cases and the introduction of PRT as a local treatment after Atez/Bev.

Complete response to tremelimumab plus durvalumab treatment in hepatocellular carcinoma with a bile duct tumor thrombus: A case report.

Tremelimumab plus durvalumab (Dur/Tre) is the first-line treatment for advanced hepatocellular carcinoma (HCC) worldwide. The present report describes the case of a 68-year-old man diagnosed with advanced HCC and a bile duct tumor thrombus (BDTT) who achieved a complete response to Dur/Tre therapy. The BDTT progressed to the bifurcation of the left and right hepatic ducts. Over time, both the tumors and BDTT progressively decreased in size, and a complete response was confirmed using the Response Evaluation Criteria in Solid Tumors (version 1.1.) 6 months after treatment administration. Subsequently, immune-related adverse events, including type 1 diabetes mellitus and diabetic ketoacidosis, emerged, leading to treatment discontinuation. The patient was undergoing outpatient follow-up in a drug-free state with no signs of recurrence 290 days after the initial administration of Dur/Tre. Although long-term and meticulous observations are required, the present findings could influence the choice of systemic chemotherapy for advanced HCC.

IFI16 Induced by Direct Interaction between Esophageal Squamous Cell Carcinomas and Macrophages Promotes Tumor Progression via Secretion of IL-1α.

Tumor-associated macrophages (TAMs), one of the major components of the tumor microenvironment, contribute to the progression of esophageal squamous cell carcinoma (ESCC). We previously established a direct co-culture system of human ESCC cells and macrophages and reported the promotion of malignant phenotypes, such as survival, growth, and migration, in ESCC cells. These findings suggested that direct interactions between cancer cells and macrophages contribute to the malignancy of ESCC, but its underlying mechanisms remain unclear. In this study, we compared the expression levels of the interferon-induced genes between mono- and co-cultured ESCC cells using a cDNA microarray and found that interferon-inducible protein 16 (IFI16) was most significantly upregulated in co-cultured ESCC cells. IFI16 knockdown suppressed malignant phenotypes and also decreased the secretion of interleukin-1α (IL-1α) from ESCC cells. Additionally, recombinant IL-1α enhanced malignant phenotypes of ESCC cells through the Erk and NF-κB signaling. Immunohistochemistry revealed that high IFI16 expression in human ESCC tissues tended to be associated with disease-free survival and was significantly associated with tumor depth, lymph node metastasis, and macrophage infiltration. The results of this study reveal that IFI16 is involved in ESCC progression via IL-1α and imply the potential of IFI16 as a novel prognostic factor for ESCC.