Colorectal cancer is a malignancy of the large intestine. Tigatuzumab is a monoclonal antibody drug designed to treat colorectal cancer by binding specifically to a cell-surface death receptor called DR5, which initiates apoptosis (programmed cell death).
A mutation in the gene SMAD4SMAD4SMAD4 leads to a non-functional transcription factor, which significantly reduces the expression of DR5 on the surface of colorectal cancer cells. Scientists measured the median percentage of cancer cells destroyed by Tigatuzumab in patients who had the SMAD4SMAD4SMAD4 mutation and those who did not.
The scientists' results are shown in Table 1.
| Patient Group | Median percentage of cancer cells destroyed by Tigatuzumab |
|---|---|
| In patients with SMAD4SMAD4SMAD4 mutation | 14 |
| In patients without SMAD4SMAD4SMAD4 mutation | 42 |
Patients with this colorectal cancer subtype have approximately 7.5×1077.5 \times 10^77.5×107 cancer cells per cm3\text{cm}^3cm3 of tumor tissue.
Use the median values in Table 1 to calculate the difference between the number of cancer cells per cm3\text{cm}^3cm3 destroyed by Tigatuzumab in patients with the wild-type gene (without the mutation) and those with the mutant SMAD4SMAD4SMAD4 gene.
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