To explore the effects of midazolam on the proliferation, invasion and apoptosis of colorectal cancer cells by regulating the liver kinase B1 (LKB1)/AMP-activated protein kinase (AMPK) signaling pathway.

Cell counting kit-8 method was used to detect the effects of different concentrations (5, 10, 20 and 40 μg·mL^-1) midazolam on the proliferation of HCT116 cells. 20 μg·mL^-1 midazolam was selected for the subsequent experiments. HCT116 cells were grouped into blank group (no treatment), midazolam group (20 μg·mL^-1 midazolam), si-NC group (transfected with si-NC plasmid), si-LKB1 group (transfected with si-LKB1 plasmid), midazolam+si-NC group (transfected with si-NC plasmid+20 μg·mL^-1 midazolam) and midazolam+si-LKB1 group (transfected with si-LKB1 plasmid+20 μg·mL^-1 midazolam). Flow cytometry, cell countig kit-8 (CCK-8), EdU and Transwell experiments were used to detect changes in cell apoptosis, proliferation and invasion. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to measure the LKB1 and AMPK mRNAs. Western blot was used to measure the proliferating cell nuclear antigen (PCNA), cysteinyl aspartate-specific protease 3 (caspase-3), matrix metalloproteinase 9 (MMP-9), liver kinase B1 (LKB1) and AMP-activated protein kinase (AMPK) proteins.

The EdU positive rates of the blank group, midazolam group, si-NC group, si-LKB1 group, midazolam + si-NC group and midazolam + si-LKB1 group were (62.52±6.38)%, (35.26±3.64)%, (61.95±6.24)%, (88.63±8.94)%, (36.05±3.71)% and (55.62±5.67)%, respectively; the proliferation rates were (90.85±9.04)%, (48.85±4.92)%, (91.04±8.92)%, (129.32±13.05)%, (49.05±4.98)% and (79.86±8.11)%, respectively; the apoptosis rates were (5.05±0.53)%, (20.22±2.15)%, (4.86±0.49)%, (3.11±0.35)%, (19.86±2.08)% and (8.77±0.91)%, respectively; the invasion numbers were 198.64±20.45, 122.53±12.37, 195.32±20.34, 286.61±29.33, 123.64±12.46 and 176.64±18.06, respectively; the relative expression levels of LKB1 mRNA were 0.93±0.10, 2.86±0.31, 1.08±0.12, 0.57±0.07, 2.78±0.29 and 1.55±0.17, respectively; AMPK mRNA were 1.06±0.11, 2.25±0.24, 0.98±0.10, 0.42±0.05, 2.19±0.23 and 1.35±0.15, respectively; the relative protein expression levels of PCNA were 0.79±0.08, 0.42±0.05, 0.81±0.09, 1.22±0.14, 0.46±0.05 and 0.68±0.07, respectively; Caspase-3 were 0.92±0.10, 1.44±0.16, 1.03±0.11, 0.51±0.06, 1.48±0.16 and 1.07±0.11, respectively; MMP-9 were 0.98±0.10, 0.52±0.06, 1.01±0.12, 1.53±0.17, 0.58±0.06 and 0.82±0.09, respectively; LKB1 were 0.31±0.03, 0.76±0.08, 0.34±0.04, 0.15±0.02, 0.72±0.08 and 0.45±0.05, respectively; AMPK were 0.44±0.05, 0.85±0.09, 0.42±0.05, 0.23±0.03, 0.80±0.09 and 0.57±0.06, respectively. For all these indicators, compared between the midazolam group and the blank group, the si-LKB1 group and the si-NC group, the midazolam + si-LKB1 group and the midazolam + si-NC group, and the si-LKB1 group, all showed statistically significant differences (all P<0.05).

Midazolam activates the LKB1/AMPK signaling pathway, inhibits the proliferation and invasion of colorectal cancer cells, and induces their apoptosis.