In one study, glipizide did not significantly suppress MTT readouts in 293T, 4T1, MCF-7 or HUVEC cultures at 1–256 μM after 48 or 72 h. This assay-specific negative result limits claims of direct antiproliferative activity in these models. [2]
Glipizide reduced HUVEC chemotactic migration after 12 h and Matrigel tube formation after 5 h at 10 and 50 μM relative to DMSO controls. These cellular findings support an angiogenesis-related phenotype under the tested conditions; they do not establish clinical anticancer efficacy. [2]
Glipizide displacement of sulfonylurea-site radioligand binding
Biochemical assay · Membranes from HEK-293 cells stably expressing human SUR1 and human Kir6.2; rat brain and RINm5F insulinoma membranes as comparisons. [1]
Glipizide displaced specific [3H]-glyburide binding with nanomolar Ki values in all three membrane preparations. Binding assays were conducted without nucleotides.
Literature-Reported Treatment Conditions
- Treatment concentration
- Glipizide concentration-response series; [3H]-glyburide 0.3 nM.
- Exposure duration
- 60 min at room temperature.
- Method
- Membrane radioligand competition assay without nucleotides.
- Vehicle
- Drug stocks in DMSO; final assay DMSO fraction not stated.
- Co-treatment
- Radioligand tracer; 1 μM unlabeled glyburide used to define specific binding.
- Reported limits
- Exact glipizide concentration series and individual sample count per table entry not enumerated in text. Table footnote: mean ± s.e.mean of 3–6 separate determinations, each in duplicate.
Methods and source locations
Compound reported in the paper: Glipizide
Results concern the named glipizide tested in this paper; no Adooq lot equivalence or salt conversion is established.
Table 1 (image and footnote); Figure 3A; Methods: Membrane preparation and ligand binding, Data analysis and statistics, Compounds; Results: Pharmacology of [3H]-glyburide binding
Displacement of specific [3H]-glyburide binding in hSUR1/hKir6.2 HEK-293 membranes: Radioligand displacement; Cheng–Prusoff conversion of fitted IC50 to Ki. — Table 1: Glipizide row, SUR1-Kir6.2 HEK-293 cells column and footnote
Displacement of specific [3H]-glyburide binding in rat brain membranes: Radioligand displacement under comparable nucleotide-free conditions. — Table 1: Glipizide row, Rat brain column and footnote
Displacement of specific [3H]-glyburide binding in RINm5F membranes: Radioligand displacement under comparable nucleotide-free conditions. — Table 1: Glipizide row, RINm5F cells column and footnote
Inhibition of diazoxide-evoked membrane-potential responses
Cell-based study · HEK-293 cells stably expressing human SUR1/human Kir6.2. [1]
Glipizide inhibited the diazoxide-evoked DiBAC4(3) fluorescence response in a concentration-dependent manner under metabolic inhibition.
Literature-Reported Treatment Conditions
- Treatment concentration
- Glipizide concentration-response series; 100 μM diazoxide.
- Exposure duration
- Fluorescence recorded for 25 min following test-compound addition.
- Method
- DiBAC4(3) membrane-potential assay at 37°C.
- Vehicle
- DMSO drug stocks; final assay DMSO fraction not stated.
- Co-treatment
- 10 mM 2-deoxyglucose and 0.1 μg/mL oligomycin used for metabolic inhibition; 100 μM diazoxide was the activating challenge.
- Reported limits
- Exact glipizide titration series and individual n for glipizide not specified in text; 25 min is the assay acquisition period.
Methods and source locations
Compound reported in the paper: Glipizide
Results concern the named glipizide tested in this paper; no Adooq lot equivalence or salt conversion is established.
Figure 7C and caption; Methods: Membrane potential studies, Compounds; Results: FLIPR-based membrane potential studies
Inhibition of the fluorescence response evoked by 100 μM diazoxide in hSUR1/hKir6.2-expressing HEK-293 cells: DiBAC4(3) fluorescence measured by FLIPR; response corrected using metabolic-inhibitor-only controls. Mean ± s.e.mean of 3–6 separate determinations as stated in Figure 7 caption. — Figure 7C caption; Results: FLIPR-based membrane potential studies
Limited effect on cell metabolic viability in MTT assays
Cell-based study · 293T human renal epithelial cells, 4T1 mouse breast cancer cells, MCF-7 human breast cancer cells, and HUVEC. [2]
The authors reported no significant suppression in MTT readouts across the tested glipizide concentrations and exposure times. MTT is a metabolic viability/proliferation proxy; these results do not establish absence of all cellular effects.
Literature-Reported Treatment Conditions
- Treatment concentration
- 1, 4, 16, 64 and 256 μM.
- Exposure duration
- 48 or 72 h.
- Method
- MTT assay with DMSO controls.
- Vehicle
- DMSO; final concentration not stated.
- Co-treatment
- Glipizide alone; no co-therapy.
- Reported limits
- Exact biological n per cell line and time point and error-bar definition are not separately given in the Figure 5 caption.
Methods and source locations
Compound reported in the paper: Glipizide
Results concern the named glipizide tested in this paper; no Adooq lot equivalence or salt conversion is established.
Results s2_5; Figure 5A–D and caption; Methods s4_2, s4_13 and s4_19
MTT readouts in 293T, 4T1, MCF-7 and HUVEC relative to DMSO controls: MTT absorbance at 570 nm; assay performed in triplicate; Figure 5 reports at least three independent experiments. — Results s2_5; Figure 5A–D and caption; Methods s4_13
Endothelial migration and tube-formation phenotypes
Cell-based study · Human umbilical vein endothelial cells (HUVEC). [2]
Glipizide reduced HUVEC migration in a Boyden-chamber assay and tube formation on Matrigel. The associated MTT study did not show significant suppression of cell metabolic viability under its longer exposures. These are angiogenesis-related cellular phenotypes, not evidence of direct NPRA binding.
Literature-Reported Treatment Conditions
- Treatment concentration
- 2, 10 and 50 μM.
- Exposure duration
- Migration: 12 h; tube formation: 5 h.
- Method
- Boyden-chamber migration and Matrigel tube-formation assays, compared with DMSO.
- Vehicle
- DMSO; final concentration not stated.
- Co-treatment
- Glipizide alone; migration assay used serum and growth-factor chemoattractants.
- Reported limits
- No numerical effect sizes transcribed from bar heights; exact independent n and error-bar definition are not separately specified.
Methods and source locations
Compound reported in the paper: Glipizide
Results concern the named glipizide tested in this paper; no Adooq lot equivalence or salt conversion is established.
Results s2_5; Figure 5E–G and caption; Methods s4_2, s4_14–15, s4_19
HUVEC chemotactic migration relative to DMSO: Boyden chamber; 12 h migration toward serum/growth-factor-containing medium. Figure 5: at least three independent experiments; *p<0.05, **p<0.01. — Figure 5E and caption; Results s2_5; Methods s4_15
HUVEC tube length on Matrigel relative to DMSO: Matrigel tube formation for 5 h; tube length quantified. Figure 5: at least three independent experiments; *p<0.05. — Figure 5F–G and caption; Results s2_5; Methods s4_14
