The provided figures and tables collectively investigate the role of GLS1 in cell growth, metabolism, and survival, particularly in the context of colorectal cancer cell lines P493 and PC3. Key findings include: 1. **GLS1 Expression**: GLS1 is predominantly expressed in P493 and PC3 cells, as confirmed by real-time quantitative PCR. HT-29 cells, known to express both GLS1 and GLS2, were used as a control. 2. **Overexpression of GLS1**: Overexpression of GLS1 in PC3 cells did not rescue the reduced growth rate caused by siRNA-mediated c-Myc knockdown, indicating that GLS1 overexpression alone is insufficient to counteract c-Myc's effects. 3. **Oxygen Consumption and ROS Production**: Depletion of GLS or glutamine decreased oxygen consumption and increased reactive oxygen species (ROS) production in P493 cells, which was mitigated by N-acetylcysteine (NAC). 4. **Glutathione Levels**: Depletion of GLS or glutamine also decreased glutathione levels in P493 and PC3 cells, further supporting the role of GLS in maintaining cellular redox balance. 5. **Cell Death**: Partial rescue of cell death induced by GLS or glutamine deprivation was observed with oxaloacetate (OAA) or NAC. 6. **Cell Proliferation**: Inhibition of cell proliferation due to GLS or glutamine deprivation was partially rescued by OAA or NAC. 7. **MicroRNA Expression**: Taqman MicroRNA assays showed that c-Myc knockdown in PC3 cells suppressed GLS-3'UTR luciferase reporter activity, suggesting a regulatory role for miR-23a and miR-23b. 8. **Correlation Analysis**: A correlation between Myc and GLS protein levels was observed in primary human prostate cancer samples, indicating a potential link between these proteins. Overall, the data highlight the complex interplay between GLS1, c-Myc, and cellular metabolism in cancer cell growth and survival.The provided figures and tables collectively investigate the role of GLS1 in cell growth, metabolism, and survival, particularly in the context of colorectal cancer cell lines P493 and PC3. Key findings include: 1. **GLS1 Expression**: GLS1 is predominantly expressed in P493 and PC3 cells, as confirmed by real-time quantitative PCR. HT-29 cells, known to express both GLS1 and GLS2, were used as a control. 2. **Overexpression of GLS1**: Overexpression of GLS1 in PC3 cells did not rescue the reduced growth rate caused by siRNA-mediated c-Myc knockdown, indicating that GLS1 overexpression alone is insufficient to counteract c-Myc's effects. 3. **Oxygen Consumption and ROS Production**: Depletion of GLS or glutamine decreased oxygen consumption and increased reactive oxygen species (ROS) production in P493 cells, which was mitigated by N-acetylcysteine (NAC). 4. **Glutathione Levels**: Depletion of GLS or glutamine also decreased glutathione levels in P493 and PC3 cells, further supporting the role of GLS in maintaining cellular redox balance. 5. **Cell Death**: Partial rescue of cell death induced by GLS or glutamine deprivation was observed with oxaloacetate (OAA) or NAC. 6. **Cell Proliferation**: Inhibition of cell proliferation due to GLS or glutamine deprivation was partially rescued by OAA or NAC. 7. **MicroRNA Expression**: Taqman MicroRNA assays showed that c-Myc knockdown in PC3 cells suppressed GLS-3'UTR luciferase reporter activity, suggesting a regulatory role for miR-23a and miR-23b. 8. **Correlation Analysis**: A correlation between Myc and GLS protein levels was observed in primary human prostate cancer samples, indicating a potential link between these proteins. Overall, the data highlight the complex interplay between GLS1, c-Myc, and cellular metabolism in cancer cell growth and survival.