1.A novel GPCR mediates pancreatic cancer associated fibroblast-cancer cell interaction
WILEY Z SHU ; SRIRAM KRISHNA ; LIANG WEN-JING ; CHANG E SARAH ; FRENCH RANDALL ; MCCANN THALIA ; NISHIHARA HIROSHI ; LOWY M ANDREW ; INSEL. A PAUL
Chinese Journal of Pharmacology and Toxicology 2017;31(10):953-953
OBJECTIVE Pancreatic ductal adenocarcinoma (PDAC), a lethal cancer in need of new, effective therapies, has a unique tumor microenvironment characterized by a dense fibrotic stroma (desmoplasia) that is generated by pancreatic cancer- associated fibroblasts (PCAFs) derived from pancreatic stellate cells (PSCs) and pancreatic fibroblasts (PFs). METHEDS and RESULTS Hypothe?sizing that G protein-coupled receptors (GPCRs) may regulate PCAFs, we used an unbiased GPCRomic array approach to compare GPCR expression in PCAFs, PFs and PSCs and identified 82 GPCRs commonly expressed by PCAFs derived from primary tumors of five PDAC patients. We discovered that PCAFs have increased expression of numerous GPCRs, in particular aGPCR with much higher expression in PCAFs compared to both PFs and PSCs. Immunohistochemistry revealed increased expression of this GPCR in PDAC tumors. Co- culture of PSCs with PDAC cells or incubation with TNFα induced its expression. Activation of the GPCR in PCAF sincreased expression of interleukin-6 (IL-6) via a cAMP/PKA/CREB signaling pathway. GPCR knockdown with siRNA diminished IL-6 production and secretionby PCAFs and ability of PCAF conditioned media to enhance proliferation of PDAC cells. CONCLUSION We conclude that PDAC cells induce expression by PCAFs of a novel GPCR, resulting in increased IL-6 production by PCAFs and promotion of PDAC cell proliferation. This PCAF-expressed GPCR thus contributes to PDAC cell-PCAF interaction and as such, may be a novel therapeutic target for PDAC tumors.
2.TP53 variants in p53 signatures and the clonality of STICs in RRSO samples
Tomoko AKAHANE ; Kenta MASUDA ; Akira HIRASAWA ; Yusuke KOBAYASHI ; Arisa UEKI ; Miho KAWAIDA ; Kumiko MISU ; Kohei NAKAMURA ; Shimpei NAGAI ; Tatsuyuki CHIYODA ; Wataru YAMAGAMI ; Shigenori HAYASHI ; Fumio KATAOKA ; Kouji BANNO ; Kokichi SUGANO ; Hajime OKITA ; Kenjiro KOSAKI ; Hiroshi NISHIHARA ; Daisuke AOKI
Journal of Gynecologic Oncology 2022;33(4):e50-
Objective:
Precursor lesions may be identified in fallopian tube tissue after risk-reducing salpingo-oophorectomy (RRSO) in patients with pathogenic variants of BRCA1/2. Serous tubal intraepithelial carcinoma (STIC) is considered a precursor of high-grade serous carcinoma, whereas the significance of the p53 signature remains unclear. In this study, we investigated the relationship between the p53 signature and the risk of ovarian cancer.
Methods:
We analyzed the clinicopathological findings and conducted DNA sequencing for TP53 variants of p53 signatures and STIC lesions isolated using laser capture microdissection in 13 patients with pathogenic variants of BRCA1/2 who underwent RRSO and 17 control patients with the benign gynecologic disease.
Results:
TP53 pathogenic variants were detected significantly higher in RRSO group than control (p<0.001). No difference in the frequency of p53 signatures were observed between groups (53.8% vs 29.4%; p=0.17). TP53 sequencing and next-generation sequencing analysis in a patient with STIC and occult cancer revealed 2 TP53 mutations causing different p53 staining for STICs and another TP53 mutation shared between STIC and occult cancer.
Conclusion
The sequence analysis for TP53 revealed 2 types of p53 signatures, one with a risk of progression to STIC and ovarian cancer with pathological variants in TP53 and the other with a low risk of progression without pathological variants in TP53 as seen in control.