Propofol Attenuates Lung but not Brain Cancer Cell Malignancy through 1 Metabolism and Cell Signaling Modulation In Vitro 2

Background: Intravenous anesthesia with propofol was reported to improve cancer surgical outcomes when compared with inhalational anesthesia. However, the underlying molecular mechanisms largely remain unknown. The current study aims to 31 investigate whether propofol affects cancer cell biology including tumor metastasis- 32 related gene expression, cellular signaling and metabolic changes in lung and brain 33 cancer cells. Methods: Lung cancer (A549) or neuroglioma (H4) cells were treated with propofol at 35 a clinically relevant concentration (4 μg/mL) for 2 hours, followed by 24 hours recovery. Tumor metastasis-related gene expressions were assessed using a PCR array and 37 validated with qRT-PCR. Glucose transporter 1 (GLUT1), brain protein 44-like 38 (BRP44L), pigment epithelium-derived factor (PEDF), Akt, phospho-Akt (p-Akt), 39 extracellular-signal-regulated kinase 1/2 (Erk1/2), phospho-Erk1/2 (p-Erk1/2), and 40 hypoxia-inducible factor 1 alpha (HIF-1α) expressions were determined using 41 immunofluorescent staining and/or western blotting. The metabolites in cell extract and 42 media following propofol treatment were characterized using proton nuclear magnetic 43 resonance ( 1 H NMR) spectroscopy. The malignant hallmarks including cell viability, 44 proliferation, migration, and invasion were evaluated using cell counting kit-8 (CCK-8) 45 assay, Ki-67 staining, wound healing and transwell assay, respectively. Results: Propofol reduced cell viability and inhibited cell proliferation, migration and invasion of lung cancer cells, but not neuroglioma cells. In lung cancer cells, gene expressions of VEGFA, CTBP1, CST7, CTSK, CXCL12, and CXCR4 were 49 downregulated, while NR4A3, RB1, NME1, MTSS1, NME4, SYK, APC, and FAT1 were 50 upregulated following the propofol treatment. Furthermore, propofol downregulated 51 GLUT1, BRP44L, p-Akt, p-Erk, and HIF-1α expressions in lung cancer cells and 52 upregulated PEDF expression. Propofol increased glutamate and glycine but 53 decreased acetate and formate in lung cancer cells whilst increased lactate, valine, 54 isoleucine, and leucine and glycerol, and decreased pyruvate and isopropanol in the 55 culture media. Consistent with the phenotypical changes, these molecular and 56 metabolic changes were not observed in the neuroglioma cells. 57 Conclusions: Our findings indicated “anti-tumor” effects of propofol on the lung cancer 58 but not neuroglioma, through the regulation of tumor metastasis-related genes, multi- 59 cellular signaling and cellular metabolism.

transcriptional activator associated with the progression of a variety of cancer types, 91 such as breast, colon, and lung cancer (12). HIF-1α can be activated by its upstream 92 effectors, such as Akt and Erk1/2 (13, 14). Akt, also known as protein kinase B, belongs 93 to the cAMP-dependent protein kinase superfamily, which is involved in many

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In the current study, the role of PEDF and HIF-1α in anti-cancer property of propofol 103 will be determined in lung and brain cancer cell cultures. We hypothesized that propofol 140 to be electrophoresed for 1.5 hour. After transferring the protein bands onto a PVDF 141 membrane, the membrane was blocked with 5% non-fat milk for 1 hour, before 142 incubation with the primary antibodies (Supplemental Table 1

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The cell media were thawed and centrifuged at 18,000 g for 10 min. A total of 540 μL 167 supernatant was mixed with 60 μL potassium phosphate buffer containing D2O, 0.1% 168 TSP, 1.5 M KH2PO4 and 2 mM NaN3. The mixture was transferred to an NMR tube with 169 an outer diameter of 5 mm pending 1 H NMR spectral acquisition.

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Tumor Metastasis (QIAGEN), which was processed and analyzed with the Rotor-Gene

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Paired oligonucleotide forward and reverse primers (Supplemental Table 2) for C-X-                In the current study, we found that propofol, one of the most commonly used 344 intravenous general anesthetic, downregulated GLUT1, BRP44L, HIF-1α, p-Akt and 345 p-Erk1/2 expressions and upregulated PEDF in lung cancer cells but not in brain 346 cancer cells (Figure 10). Furthermore, 6 pro-tumor genes were downregulated and 8

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In this study, propofol was found to inhibit GLUT1 and BRP44L expressions, which 355 were located at the cellular and mitochondrial membrane, respectively. In line with our 356 data, propofol was previously reported to suppress GLUT1 expression in human

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Our PCR array results showed that several pro-tumor (for example, VEGFA, CXCL12, 430 and CXCR4) genes were downregulated and anti-tumor genes (for example, RB1, 431 APC, and FAT1) were upregulated (Supplemental Table 5). These were in contrast to 432 volatile anesthetics which induced the tumor metastatic related genes that were 433 associated with the enhanced malignancy of ovarian cancer cells (10). Interestingly, a 434 retrospective clinical study showed that patients received tumor resection were 435 grouped into total intravenous anesthesia (propofol and remifentanil) or inhalational 436 anesthesia (isoflurane or sevoflurane) groups. It was found that patients received 437 inhalational anesthesia during cancer surgery had a lower 3 year-survival rate than 438 those received propofol-based intravenous anesthesia (9). In another study, it was 439 concluded that propofol-based intravenous anesthesia for colon cancer surgery was 440 associated with better survival rate than desflurane-based inhalational anesthesia (50).

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Arguably, these clinical data are well supported by our current findings that propofol 442 inhibits the malignancy of cancer cells, albeit derived from lung cancer.