Panoply™ Human PKLR Over-expressing Stable Cell Line

Neuroendocrine differentiation (NED) is common in androgen deprivation therapy (ADT)-resistant prostate cancer (PCa) and is typically associated with altered metabolic pathways, lineage plasticity gain, and malignant transformation. Due to the lack of clear molecular targets, there are currently no standard treatments for PCa patients with NED pathology. Here, researchers evaluated the regulatory mechanisms of ADT-induced NED-related metabolic reprogramming. They found that the loss of androgen-responsive transcription factors zinc finger proteins and BTB domain protein 10 (ZBTB10) activates pyruvate kinase L/R (PKLR), thereby enhancing the NED response associated with glucose uptake in PCa cells. Following ADT, PKLR exhibits a pro-tumorigenic effect in PCa, but ZBTB10 can compensate for PKLR's glucose metabolism and NED capacity by directly downregulating PKLR transcriptionally. Using FDA-approved compounds for drug retargeting, targeting PKLR can reduce the invasiveness and neuroendocrine dysfunction (NED) in ADT-resistant prostate cancer. Researchers have demonstrated that PKLR, as a regulator, activates NED through the loss of ZBTB10, thereby enhancing the invasiveness of prostate cancer and enabling prostate cancer cells to initiate glycolysis, which is crucial for treatment resistance. These findings highlight the broad association between NED and metabolic dysfunction and provide gene-expression-based biomarkers for the treatment of neuroendocrine prostate cancer (NEPC).

Regarding the functional role of PKLR in PCa progression, researchers found that PKLR-overexpressing C4-2 cells exhibited a statistically significant increase in growth rate in vitro (Figure 1A). However, compared with cells carrying the control vector, PKLR-knockdown PC3 cells showed a decreased growth rate (Figure 1B). Furthermore, three-dimensional spheroid formation assays showed that in Matrigel, PKLR-overexpressing C4-2 cells and PKLR-knockdown PC3 cells exhibited significantly enhanced or diminished spheroid formation abilities, respectively (Figure 1C, D). Immunoblotting experiments confirmed the expression of PKLR protein in PKLR-modified cells (Figure 1E). To evaluate the potential tumor-suppressive role of ZBTB10 in downregulated PKLR-driven prostate cancer (PCa) progression, researchers used a stable ZBTB10-expressing clone and compared it with ZBTB10-expressing cells rescued from AR-positive LNCaP and C4-2 cells using a PKLR cDNA vector. MTT analysis showed that the growth rate of ZBTB10 overexpressing cells was significantly reduced compared to cells carrying the control vector; however, the cell proliferation rate was higher in PKLR-rescued ZBTB10-expressing cells (Figure 1F, G). Consistent with this, the spheroidization ability of ZBTB10-expressing cells was reduced, while the spheroidization ability of ZBTB10-expressing cells rescued with the PKLR cDNA vector was enhanced (Figure 1H).

Figure 1. PKLR rescues ZBTB10-suppressed malignancy of PCa. (Wen Y C, et al., 2022)