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Human growth hormone (GH) is crucial modulator of cellular metabolisms, including cell proliferation and organ development, by stimulating insulin-like growth factor-1 (IGF-1), which has various functions such as cell proliferation, tissue growth, survival, or neuroprotection. Therefore, GH is implicated as a critical player in the cell and can enhance neurogenesis and provide neuroprotection during the treatment of neurological diseases such as Parkinson's disease (PD). In this study, the neuroprotective role of GH was investigated in rotenone-induced PD models for the first time. Both SH-SY5Y and SK-N-AS neuroblastoma cells were exposed to rotenone to mimic PD pathogenesis as stated in previous studies. Our data demonstrated that overexpression of GH led to the resistance of the SH-SY5Y and SK-N-AS cell lines to rotenone treatment. The levels of ER stress markers, CHOP, PERK, XBP-1, and ATF6, were higher in wt cells than GH+ SH-SY5Y cells. However, the level of autophagy markers LC3 increased and the levels of reactive oxygen species (ROS) decreased with the overexpression of GH. Furthermore, while rotenone significantly increased the SubG1 population in the cell cycle of SH-SY5Y wt cells, there was a minor alteration in GH+ cell population. Concomitantly, the levels of the proapoptotic marker, cleaved-PARP, and positive staining of Annexin V in SH-SY5Y wt cells were higher after rotenone treatment. Together, these results revealed that overexpression of GH enhanced the autophagy response by triggering the ER stress of SH-SY5Y cells to rotenone exposure and showed a neuroprotective effect in vitro PD models.

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The prognostic characteristics of pancreatic cancer (PC) are determined by the contributing factors from the tumor microenvironment. Leptin is a critical oncogenic factor released by adipocytes as an adipokine into the tumor microenvironment, where it promotes tumor development by activating cancer stem cell (CSC) molecular regulators Notch, Hedgehog, and Wnt/ß-catenin signaling. One of the downstream targets of these pathways is CDK4/6 and cyclin D which is controlled by P16 INK4A that is highly mutated in PC. Therefore, the purpose of this study was to determine the effect of a CDK4/6 inhibitor, palbociclib, on Leptin-induced PC cells and to target the Notch, Hedgehog, and Wnt/ß-catenin signaling pathways via miR-150, miR-506, and miR-208 modulation. Leptin treatment increased the ability of Panc-1, MiaPaCa-2, and Capan-2 cells to proliferate and decreased the effect of palbociclib. Additionally, tumorspheres were generated from Leptin-treated (Leptin+) and Leptin-untreated (Leptin-) Panc-1 and MiaPaCa-2 cells and transfected with miR-506, miR-150 (tumorsuppressor miRNAs), or anti-miR-208 (oncomiR), followed by palbociclib treatment. Forced expression of miR-506 or miR-150 significantly increased the susceptibility of Leptin+ cells to palbociclib treatment by inhibiting colony and tumor spheroid formation, and CD44 expression in Panc-1 and MiaPaCa-2 cells. Additionally, the increased miR-150 expression is more effective at inhibiting N-cadherin, ß-catenin, p-GSK3ß, Notch, and Wnt5a/b expression in Leptin-/+ Panc-1 and MiaPaCa-2 cells. As a result, palbociclib suppressed the CSC profile induced by leptin treatment, inhibiting both tumorsphere forms and leptin-targeted signaling pathways, thereby disabling the Panc-1 and MiaPaCa-2 cells' resistance mechanism. Increased expression of miR-506 or miR-150 and inhibition of miR-208 enhanced sensitivity of Panc-1 and MiaPaCa-2 Leptin-/+ cells to palbociclib treatment. As a result, this study proved that combining inhibitors of CSC molecular regulators with palbociclib improves the success rate of inhibition of PC cell proliferation.

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Gemcitabine is a broad-spectrum antimetabolite and a deoxycytidine analog recognized as a standard therapy alone or in combination with other antineoplastic agents in the therapy of pancreas cancer. Drug resistance following gemcitabine treatment is a common phenomenon; therefore, combinational therapy models are usually preferred. Pancreatic ductal adenocarcinoma, or pancreas cancer, is the fourth leading cause of cancer-related deaths worldwide. With the increasing incidence of pancreatic cancer every year, the mortality rate is also rising significantly because of late diagnosis, and limited chemotherapy options. Adjuvant chemotherapy after surgical resection is the typical option for the treatment of early pancreatic cancer. Mostly, 5-fluorouracil/leucovorin with irinotecan and oxaliplatin (FOLFIRINOX) and gemcitabine/nab-paclitaxel is used for the prognosis of advanced pancreatic cancer; however, chemoresistance usually occurs limiting the effectiveness of the chemotherapy. Therefore, most of the studies are focused on gemcitabine combination with other drugs to overcome the situation. As an apoptotic agent and a member of brassinosteroids, epibrassinolide (EBR) induces endoplasmic reticulum (ER) stress-dependent cell death in different cancer cells, as shown by our group. In this study, we aimed to enhance the gemcitabine apoptotic effect by EBR combined treatment in pancreatic cancer cells. EBR treatment reduced cell viability and inhibited cell proliferation in PANC-1, MIA PaCa-2, and AsPC-1 cells. Each pancreatic cancer cell gave different responses to the EBR treatment because of different aggressiveness. However, EBR induced apoptosis through increasing ROS generation, which was associated with ER stress in PANC-1 and MIA PaCa-2 cells. Gemcitabine alone reduced the cell viability of each pancreatic cancer cell line; however, combination with EBR led to further induction of apoptotic cell death in each pancreatic cancer cell line. In addition, combined treatment of gemcitabine and EBR further decreased N-cadherin and vimentin expressions, suggesting that epithelial-mesenchymal transition of pancreatic cells is reduced. In conclusion, EBR had therapeutic potential to avoid the gemcitabine-induced side effects during the treatment of pancreatic cancer.

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Fatty acids (FAs) synthesis mechanism has various regulators such as fatty acid synthase (FASN), AMP-regulated protein kinase (AMPK), or mammalian target of rapamycin (mTOR), which are aberrantly dysregulated in various pancreatic cancer cells. In this study, we aim to understand the regulatory role of palbociclib, a CDK4/6 inhibitor, on the cellular energy metabolism through regulation of AMPK/mTOR signaling by modulation of intracellular miR-33a levels in Panc-1 and MiaPaCa-2 cells. Palbociclib downregulated FAs metabolism more effectively in MiaPaCa-2 cells than Panc-1 cells. Moreover, palbociclib treatment increased the levels of miR-33a in each cell line albeit a higher increase was evident in MiaPaCa-2 cells. Stress-mediated activation of mTOR signaling axis was found associated with palbociclib-mediated AMPKα activation and miR33a upregulation. These findings provided that a deeper understanding about possible interactions of cell cycle activity and reduction of FAs synthesis may facilitate the enhancement of cell death mechanisms in pancreatic cancer cells.

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Breast cancer (BCa) is one of the leading health problems among women. Although significant achievements have led to advanced therapeutic success with targeted therapy options, more efforts are required for different subtypes of tumors and according to genomic, transcriptomic, and proteomic alterations. This study underlines the role of microRNA-21 (miR-21) in metastatic MDA-MB-231 breast cancer cells. Following the knockout of miR-21 from MDA-MB-231 cells, which have the highest miR-21 expression levels compared to MCF-7 and SK-BR-3 BCa cells, a decrease in epithelial-mesenchymal transition (EMT) via downregulation of mesenchymal markers was observed. Wnt-11 was a critical target for miR-21, and the Wnt-11 related signaling axis was altered in the stable miR-21 knockout cells. miR-21 expression was associated with a significant increase in mesenchymal markers in MDA-MB-231 BCa cells. Furthermore, the release of extracellular vesicles (EVs) was significantly reduced in the miR-21 KO cells, alongside a significant reduction in relative miR-21 export in EV cargo, compared with control cells. We conclude that miR-21 is a leading factor involved in mesenchymal transition in MDA-MB-231 BCa. Future therapeutic strategies could focus on its role in the treatment of metastatic breast cancer.

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Prostate cancer (PCa) is one of the most common cancers among men, and one of the leading causes of cancer death for men. The c-Jun N-terminal kinase (JNK) pathway is required for several cellular functions, such as survival, proliferation, differentiation, and migration. Wnt-11, a member of the Wnt family, has been identified for its upregulation in PCa; however, downstream signalling of Wnt-11 remains to be fully characterized. In this study, we investigated the role of the JNK pathway as a potential downstream factor for Wnt-11 signalling. For this purpose, LNCaP, DU145, and PC-3 PCa cells and normal epithelial PNT1A cells were treated with a specific JNK kinase inhibitor: JNKVIII. Our results showed that JNK inhibition decreased mitochondrial membrane potential and promoted cell death in a cell type-dependent manner. We found that JNK inhibition led to an increase in autophagy and prevented epithelial-mesenchymal transition (EMT) in independently growing androgen cells. JNK inhibition and the silencing of Wnt-11 showed similar responses in DU145 and PC-3 cells and decreased metastasis-related biomarkers, cell migration, and invasion. Overall, our results suggest that JNK signalling plays a significant role in the pathophysiology of PCa by mediating Wnt-11 induced signals. Our data highlights that both the JNK pathway and Wnt-11 could be a useful therapeutic target for the combinatory application of current PCa.

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: Prostate cancer (PCa) is the second-leading cause of cancer-related death among men. microRNAs have been identified as having potential roles in tumorigenesis. An oncomir, miR-21, is commonly highly upregulated in many cancers, including PCa, and showed correlation with the Wnt-signaling axis to increase invasion. Wnt-11 is a developmentally regulated gene and has been found to be upregulated in PCa, but its mechanism is unknown. The present study aimed to investigate the roles of miR-21 and Wnt-11 in PCa in vivo and in vitro. First, different Gleason score PCa tissue samples were used; both miR-21 and Wnt-11 expressions correlate with high Gleason scores in PCa patient tissues. This data then was confirmed with formalin-fixed paraffin cell blocks using PCa cell lines LNCaP and PC3. Cell survival and colony formation studies proved that miR-21 involves in cells' behaviors, as well as the epithelial-mesenchymal transition. Consistent with the previous data, silencing miR-21 led to significant inhibition of cellular invasiveness. Overall, these results suggest that miR-21 plays a significant role related to Wnt-11 in the pathophysiology of PCa.

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The mortality rate of pancreatic cancer has close parallels to its incidence rate because of limited therapeutics and lack of effective prognosis. Despite various novel chemotherapeutics combinations, the 5-year survival rate is still under 5%. In the current study, we aimed to modulate the aberrantly activated PI3K/AKT pathway and epithelial-mesenchymal transition (EMT) signaling with the treatment of CDK4/6 inhibitor PD-0332991 (palbociclib) in Panc-1 and MiaPaCa-2 pancreatic cancer cells. It was found that PD-0332991 effectively reduced cell viability and proliferation dose-dependently within 24 hours. In addition, PD-0332991 induced cell cycle arrest at the G1 phase by downregulation of aberrant expression of CDK4/6 through the dephosphorylation of Rb in each cell lines. Although PD-0332991 treatment increased epithelial markers and decreased mesenchymal markers, the nuclear translocation of ß-catenin was not prevented by PD-0332991 treatment, especially in MiaPaCa-2 cells. Effects of PD-0332991 on the regulation of PI3K/AKT signaling and its downstream targets such as GSK-3 were cell type-dependent. Although the activity of AKT was inhibited in both cell lines, the phosphorylation of GSK-3ß at Ser9 increased only in Panc-1. In conclusion, PD-0332991 induced cell cycle arrest and reduced the cell viability of Panc-1 and MiaPaCa-2 cells. However, PD-0332991 differentially affects the regulation of the PI3K/AKT pathway and EMT process in cells due to its distinct influence on Rb and GSK-3/ß-catenin signaling. Understanding the effect of PD-0332991 on the aberrantly activated signaling axis may put forward a new therapeutic strategy to reduce the cell viability and metastatic process of pancreatic cancer.

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BACKGROUND: Prostate cancer is the most common type of cancer among men. Studies showed that the regular use of nonsteroidal antiinflammatory drugs might reduce disease progression risk for prostate cancer patients with prostate cancer. We evaluated the effects of ectopic expression of p53 on the biological functions of ibuprofen and diclofenac. MATERIALS AND METHODS: For this purpose, We investigated cell death decision pathways related to survival and aggressive cellular phenotypes such as extrinsic/intrinsic apoptosis decision, Protein Kinase B/ Forkhead box O (AKT/FoxO) axis, mitogen-activated protein kinases (MAPKs), reactive oxygen species (ROS) generation, and EMT (epithelial mesenchymal transition) in wild type and p53 + PC3 prostate cancer cells. RESULTS AND CONCLUSIONS: Ibuprofen (1 mM) and diclofenac (250 µM) effectively induced cell cycle arrest and led to apoptosis via modulating both extrinsic and intrinsic pathways. However, diclofenac was the only drug to generate ROS intermediates. Diclofenac triggered a typical EMT process with downregulated E-cadherin and upregulated N-cadherin, vimentin, and Snail in PC3 cells, regardless of p53 expression. In conclusion, although both drugs are effective on cell death mechanism, only diclofenac caused EMT because of increased ROS generation independent of p53. On the other hand, ibuprofen could inhibit metastasis via upregulating E-cadherin. The biological targets of both nonsteroidal antiinflammatory drugs are different to highlight their role in cell survival and death axis.

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Purvalanol and roscovitine are specific cyclin-dependent kinase (CDK) inhibitors, which have antiproliferative and apoptotic effects on various types of cancer. Although, the apoptotic accomplishment of purvalanol and roscovitine was elucidated at the molecular level, the underlying exact of drug-induced apoptosis through mitogen-activated protein kinase (MAPK) signaling still speculative. In addition, the role of CDK inhibitors in the downregulation of extracellular signal-regulated kinase 1/2 (ERK1/2)-mediated epithelial-mesenchymal transition (EMT) remains unclear. Here, we investigated the potential effect of each CDK inhibitors on cell proliferation, migration, and generation of reactive oxygen species due to the inhibition of MAPKs in metastatic DU145 and PC3 prostate cancer cells. We reported that purvalanol and roscovitine induced mitochondria membrane potential loss-dependent apoptotic cell death, which was also characterized by activation of several caspases, cleavage of poly (ADP-ribose) polymerase-1 in DU145 and PC3 cells. Cotreatment of either purvalanol or roscovitine with ERK1/2 inhibitor, U0126, synergistically suppressed cell proliferation, and induced apoptotic action. Also, ERK1/2 inhibition potentiated the effect of each CDK inhibitor on the downregulation of EMT processes via increasing the epithelial marker and decreasing mesenchymal markers through reduction of Wnt signaling regulators in DU145 cells. This study provides biological evidence about purvalanol and roscovitine have apoptotic and antimetastatic effects via MAPK signaling on prostate cancer cell by activation of GSK3ß signaling and inhibition of phosphoinositide-3-kinase/AKT (PI3K/AKT) pathways involved in the EMT process.

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Diclofenac is a preferential cyclooxygenase 2 inhibitor (COX-2) and member of non-steroidal anti-inflammatory drugs (NSAIDs). Inflammation is one of the main reason of poor prognosis of colon cancer cases; thereby NSAIDs are potential therapeutic agents in colon cancer therapy. In this study, our aim to understand the potential molecular targets of diclofenac, which may propose new therapeutic targets in HCT 116 (wt p53) and SW480 (mutant p53R273H) colon cancer cells. For this purpose, we identified different response against diclofenac treatment through expression profiles of PI3K/Akt/MAPK signaling axis. Our hypothesis was diclofenac-mediated apoptosis is associated with inhibition of PI3K/Akt/MAPK signaling axis. We found that sub-cytotoxic concentration of diclofenac (400 µM) promoted further apoptosis in HCT 116 cells compared to SW480 colon cancer cells. Diclofenac triggered dephosphorylation of PTEN, PDK, Akt, which led to inhibition of PI3K/Akt survival axis in HCT 116 colon cancer cells. However, diclofenac showed lesser effect in SW480 colon cancer cells. In addition, diclofenac further activated p44/42, p38 and SAPK/JNK in HCT 116 cells compared to SW480 cells.

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