[Protein kinase D1 regulates the growth and metabolism of oral squamous carcinoma cells in tumor microenvironment]. Wang Li-Wei,Yu Yu,Chen Jiao,Feng Yun,Cui Bo-Miao,Li Xiao-Ying,Wang Jing-Nan,Chen Hong-Li,Zhang Ping Hua xi kou qiang yi xue za zhi = Huaxi kouqiang yixue zazhi = West China journal of stomatology OBJECTIVE:To observe the effect of protein kinase D1 (PKD1) on the growth and metabolism of oral squamous cell carcinoma HSC-4 cells and related molecular mechanisms in the tumor microenvironment. METHODS:HSC-4 cell lines were transfected with shRNA plasmids. Three groups (Wild, control-shRNA, and PKD1-shRNA) were cultured under acidic or hypoxic environment for a certain time. Western blot was used to detect the expression of autophagy-related and glycolytic-related proteins. The proliferation changes were detected by CCK-8 kits. RESULTS:The PKD1-knockdown HSC-4 cell line was established. PKD1 silencing increased autophagy activity. Under hypoxic and acidic conditions, the PKD1-knockdown HSC-4 cells showed lower proliferation than the parental cells. PKD1-knockdown also decreased the expression of hypoxia induciblefactor 1α (HIF-1α) and pyruvate kinase M2 (PKM2). CONCLUSIONS:Under hypoxic and acidic conditions, PKD1 gene silencing can increase apoptotic autophagy activity. Downregulated PKD1 gene expression can reduce the glycolysis of oral squamous cell carcinoma cells and inhibit tumor cell proliferation. This study revealed the important role of PKD1 in the metabolism and growth of oral squamous cell carcinoma, making it a possible target for the treatment of oral squamous cell carcinoma. 10.7518/hxkq.2019.06.002

Protein kinase D1 regulates metabolic switch in pancreatic cancer via modulation of mTORC1. Kumari Sonam,Khan Sheema,Sekhri Radhika,Mandil Hassan,Behrman Stephen,Yallapu Murali M,Chauhan Subhash C,Jaggi Meena British journal of cancer BACKGROUND:Protein kinase D1 (PKD1) is a serine-threonine kinase that regulates various functions within the cell. Herein, we report the significance of PKD1 expression in glucose metabolism resulting in pancreatic cancer (PanCa) progression and chemo-resistance. METHODS:PKD1 expression in PanCa was investigated by using immunohistochemistry. Functional and metabolic assays were utilised to analyse the effect of PKD1 expression/knockdown on associated cellular/molecular changes. RESULTS:PKD1 expression was detected in human pancreatic intraepithelial neoplasia lesions (MCS = 12.9; P < 0.0001) and pancreatic ductal adenocarcinoma samples (MCS = 15, P < 0.0001) as compared with faint or no expression in normal pancreatic tissues (MCS = 1.54; P < 0.0001). Our results determine that PKD1 enhances glucose metabolism in PanCa cells, by triggering enhanced tumorigenesis and chemo-resistance. We demonstrate that mTORC1 activation by PKD1 regulates metabolic alterations in PanCa cells. siRNA knockdown of Raptor or treatment with rapamycin inhibited PKD1-accelerated lactate production as well as glucose consumption in cells, which confirms the association of mTORC1 with PKD1-induced metabolic alterations. CONCLUSION:This study suggests a novel role of PKD1 as a key modulator of the glucose metabolism in PanCa cells accelerating tumorigenesis and chemo-resistance. The remodelling of PKD1-dysregulated glucose metabolism can be achieved by regulation of mTORC1 for development of novel therapeutic strategies. 10.1038/s41416-019-0629-9

Protein Kinase D1 (PKD1) Is a New Functional Non-Genomic Target of Bisphenol A in Breast Cancer Cells. Merzoug-Larabi Messaouda,Youssef Ilige,Bui Ai Thu,Legay Christine,Loiodice Sophia,Lognon Sophie,Babajko Sylvie,Ricort Jean-Marc Frontiers in pharmacology Exposure to bisphenol A (BPA), one of the most widespread endocrine disruptors present in our environment, has been associated with the recent increased prevalence and severity of several diseases such as diabetes, obesity, autism, reproductive and neurological defects, oral diseases, and cancers such as breast tumors. BPA is suspected to act through genomic and non-genomic pathways. However, its precise molecular mechanisms are still largely unknown. Our goal was to identify and characterize a new molecular target of BPA in breast cancer cells in order to better understand how this compound may affect breast tumor growth and development. By using (MCF-7, T47D, Hs578t, and MDA-MB231 cell lines) and models, we demonstrated that PKD1 is a functional non-genomic target of BPA. PKD1 specifically mediates BPA-induced cell proliferation, clonogenicity, and anchorage-independent growth of breast tumor cells. Additionally, low-doses of BPA (≤10 M) induced the phosphorylation of PKD1, a key signature of its activation state. Moreover, PKD1 overexpression increased the growth of BPA-exposed breast tumor xenografts in athymic female Swiss nude ( ) mice. These findings further our understanding of the molecular mechanisms of BPA. By defining PKD1 as a functional target of BPA in breast cancer cell proliferation and tumor development, they provide new insights into the pathogenesis related to the exposure to BPA and other endocrine disruptors acting similarly. 10.3389/fphar.2019.01683

PKD1 is a potential biomarker and therapeutic target in triple-negative breast cancer. Spasojevic Caroline,Marangoni Elisabetta,Vacher Sophie,Assayag Franck,Meseure Didier,Château-Joubert Sophie,Humbert Martine,Karam Manale,Ricort Jean Marc,Auclair Christian,Regairaz Marie,Bièche Ivan Oncotarget Protein Kinase D1 (PKD1) is a serine/threonine kinase encoded by the gene. PKD1 has been previously shown to be a prognostic factor in ERα+ tamoxifen-resistant breast tumors and PKD1 overexpression confers estrogen independence to ERα+ MCF7 cells. In the present study, our goal was to determine whether PKD1 is a prognostic factor and/or a relevant therapeutic target in breast cancer. We analyzed mRNA levels in 527 primary breast tumors. We found that high mRNA levels were significantly and independently associated with a low metastasis-free survival in the whole breast cancer population and in the triple-negative breast cancer (TNBC) subtype specifically. High mRNA levels were also associated with a low overall survival in TNBC. We identified novel PKD1 inhibitors and assessed their antitumor activity in TNBC cell lines and in a TNBC patient-derived xenograft (PDX) model. Pharmacological inhibition and siRNA-mediated depletion of PKD1 reduced colony formation in MDA-MB-436 TNBC cells. PKD1 inhibition also reduced tumor growth in a TNBC PDX model. Together, these results establish PKD1 as a poor prognostic factor and a potential therapeutic target in TNBC. 10.18632/oncotarget.25292