The first-line antihypertensive nitrendipine potentiated the therapeutic effect of oxaliplatin by downregulating CACNA1D in colorectal cancer

Figures

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  Figure 1. NTD inhibited the cell proliferation and migration viability of CRC cells. (a)–(c) Dose–response examination of NTD in MC38 (a), RKO (b), and HT29 cells (c). (d) IC50 values of NTD for MC38, RKO, or HT29. (e) and (f) NTD (100 μM) suppressed the ability of colony formation of MC38 cells. (g) and (h) NTD (100 μM) suppressed the ability of colony formation of RKO cells. (i) and (j) NTD (100 μM) and OXA (6.25 μM) inhibited the migration ability of RKO cells. a, analysis of variance performed between multiple groups.

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  Figure 2. NTD synergistically enhances the cytotoxicity of OXA against CRC cells. MC38 (a), RKO (b), and HT29 cells (c). (d) IC50 values of OXA for MC38, RKO, or HT29. (e)–(g) Heatmaps of drug combination responses. NTD and OXA synergistically inhibited MC38 (e), RKO (f), or HT29 (g) cell growth in vitro. MC38, RKO, or HT29 cells were treated with NTD and OXA at the indicated concentrations for 48 h, and CCK-8 was employed to detect cell viability. SynergyFinder software was used to calculate the ZIP Synergy scores. Scores > 0: synergism, and scores > 10: strongly synergistic. The gradation of the red regions revealed synergism intensity. The white rectangle displayed the concentrations encompassing the region of highest synergy, and the X- and Y-axes corresponding to the sides of the white rectangle demonstrate the concentrations at which the drug combination exerts the maximum inhibitory impact on cell proliferation. (h) and (i) The combination of OXA (12.5 μM) plus NTD (100 μM) enhanced the colony formation of MC38 cells. (j) CCK-8 detection of cell viability of RKO cells after being treated with OXA (12.5 μM) plus NTD (100 μM) for 48 h. (k) CCK-8 detection of cell viability of HT29…

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  Figure 3. NTD inhibited CRC progression and enhanced OXA therapeutic effect in vitro by downregulating CACNA1D. (a) Data from the GEO were utilized to analyze CACNA1D expression in colon tumor tissues. (b) IHC detection data of CACNA1D expression in colon tumor tissues downloaded from the HPA database (www.proteinatlas.org), scale bar, 100 μm. (c) Data from the GEO were utilized to analyze the CACNA1D expression in rectum tumor tissues. (d) IHC detection data of CACNA1D expression in rectum tumor tissues downloaded from the HPA database (www.proteinatlas.org), scale bar, 100 μm. (e) qPCR detection of CACNA1D expression of FHC and CRC cell lines. (f) WB detection of CACNA1D expression of FHC and CRC cell lines. (g) qPCR detection of CACNA1D expression in MC38 after NTD treatment. (h) qPCR detection of CACNA1D expression in RKO after NTD treatment. (i) The efficiency of CACNA1D knockdown in MC38 and RKO was examined by qPCR assay. (j) Cell viability of MC38 after CACNA1D knockdown and with the addition of NTD (100 μM) for 48 h. (k) Cell viability of RKO after knocking down CACNA1D and being treated by NTD (100 μM) for 48 h. (l) Cell viability of MC38 after CACNA1D knockdown and upon with the…

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  Figure 4. NTD potentiates OXA inhibition on CRC in vivo by downregulating CACNA1D. (a) The scheme of scramble and shCACNA1D MC38 subcutaneous tumors after receiving combination therapy of NTD and OXA. (b) Photo of MC38/scramble group subcutaneous tumor(control group [n = 7], NTD group [n = 7], OXA group [n = 7], OXA + NTD group [n = 7]). (c) Growth curve of MC38/scramble group tumor. (d) Weight of MC38/scramble group tumor. (e) Photo of MC38/shCACNA1D group subcutaneous tumor (shCACNA1D group (n = 7), NTD + shCACNA1D group (n = 7), OXA + shCACNA1D group (n = 7), and OXA + NTD + shCACNA1D group (n = 7)). (f) Growth curve of MC38/shCACNA1D group tumor. (g) Weight of MC38/shCACNA1D group tumor. a, analysis of variance performed between multiple groups.