Fig 2: Suppression of IGF-1R alters key signaling molecules in PANC-1 and HPAC cells.(A, C & E): The effect of IGF-1R suppression on AKT/PI3K signaling was examined in pancreatic cancer cells. PANC-1 and HPAC cells were treated with IGF-1R siRNA for 48 h. The cells were harvested and the expression of phospho-AKT, AKT, phospho-PI3K, PI3K, phospho-PTEN, phospho-mTOR, mTOR, phospho-p70s6kinase, p70s6kinase and the internal control β-actin was measured by Western blotting. (B, D & F): Densitometric analysis is also shown to the right of each representative image.

Fig 3: Long-term exposure to 3,5,3′-triiodothyronine (T3) is required to induce thyroid hormone receptor beta (TRβ)-mediated suppression of the phosphoinositide 3 kinase–protein kinase B–mechanistic target of rapamycin (PI3K-Akt-mTOR) pathway. SW1736-EV (empty vector; EV) and SW1736-TRβ (TRβ) cells were treated with 10-nM T3 for 24 hours before protein levels were determined by immunoblot (A and quantified in C) or B, subjugated to a pAkt Ser473 sandwich enzyme-linked immunosorbent assay (ELISA). The samples in A are biological replicates. Dashed lines in immunoblots indicate gap between 2 sets of lanes on the same membrane. ELISA signal in B was standardized to protein concentration as determined by a Bradford assay. Significance in B and C was calculated by t test. NS, no significance (P ≥ .05, *P < .05, **P < .01, ***P < .001).

Fig 4: Schematic regulation of PDP1 in PDAC. Overexpression of PDP1 may activate PDH, which in turn accelerates the TCA cycle, which provides reducing equivalents in the form of NADH, FADH2, etc. for the ATP production by oxidative phosphorylation. The abundance of cellular ATP inhibits AMPK activation, restoring the mTOR signaling that can promote proliferation and invasion of PDAC cells

Fig 5: Involvement of calcium-dependent PKCa/mTOR pathway in cP1P-induced HIF1a expression.a UCB-MSCs were pretreated with EDTA (2 mM), BAPTA-AM (10 µM), VPC23019 (1 µM), or JTE013 (10 µM), and incubated with fluo-3-AM for 30 min prior to calcium influx measurement with pretreatment of vehicle, cP1P (1 µM), or A23187 (1 µM). b UCB-MSCs were treated with cP1P (1 µM) for 0, 15, or 30 min. p-pan PKC (ßII Ser660), PKC, and ß-Actin were detected by western blotting. n = 3. c, d UCB-MSCs were pretreated with BAPTA-AM (10 µM) for 30 min prior to cP1P (1 µM) for 30 min. c PKCa and pan-cad protein expressions in membrane fraction samples were detected by western blotting. n = 3. d Total protein expressions of p-PKCa, PKCa, and ß-Actin were detected by western blotting. n = 4. e UCB-MSCs were pretreated with BAPTA-AM (10 µM) for 30 min prior to cP1P (1 µM) for 24 h. Total protein expression levels of HIF1a and ß-Actin were detected by western blotting. n = 3. f UCB-MSCs were transfected with PKCA or NT siRNA for 24 h prior to cP1P (1 µM) for 30 min. The protein expressions of p-Akt (Thr308), p-Akt (Ser473), Akt, p-mTOR (Ser2448), p-mTOR (Ser2481), mTOR, p-S6K1 (Thr389), S6K1, PKCa, and ß-Actin were detected by western blotting. n = 3. g UCB-MSCs were pretreated with Akt inhibitor (2 µM) for 30 min prior to cP1P (1 µM) for 30 min. p-mTOR (Ser2448), p-mTOR (Ser2481), mTOR, and ß-Actin were detected by western blotting. n = 3. h, i UCB-MSCs were pretreated with rapamycin (100 nM) or PF4708671 (10 µM) for 30 min prior to cP1P (1 µM) for 24 h. HIF1a and ß-Actin protein expressions were detected by western blotting. n = 3–4. j, k UCB-MSCs were transfected with RPTOR or NT siRNA for 24 h prior to cP1P (1 µM) for 24 h. j RAPTOR, HIF1a and ß-Actin protein expressions were detected by western blotting. n = 3. k HIF1 activities were assessed by dual luciferase reporter assay. n = 6. All blot images are representative. Quantitative data are presented as a mean ± S.E.M with scatter plots. * indicates p < 0.05