The most commonly used marker enzyme in clinical diagnosis of prostate cancer is:

Options

A. Amylase
B. `gamma`-GTPase
C. Alkaline phosphatase
D. Acid phosphatase

Answer

**Step-by-Step Solution:**

1. **Understanding Prostate Cancer**: Start by recognizing that prostate cancer is a common condition affecting the prostate gland, which is part of the male reproductive system. The prostate gland is located below the bladder and plays a crucial role in providing nourishment to sperm.

2. **Identifying Marker Enzymes**: In clinical diagnostics, specific enzymes can serve as markers for diseases. For prostate cancer, we need to identify which enzyme is most commonly used as a marker.

3. **Evaluating the Options**: The options provided are:
- A) Amylase
- B) Gamma GTPase
- C) Alkaline phosphatase
- D) Acid phosphatase

4. **Analyzing Each Option**:
- **Amylase**: This enzyme is involved in the hydrolysis of starch and is not related to prostate cancer.
- **Gamma GTPase**: This enzyme is associated with cell growth and signaling, not specifically with prostate cancer.
- **Alkaline Phosphatase**: This enzyme is a marker for liver and bone disorders, but not specifically for prostate cancer.
- **Acid Phosphatase**: This enzyme is known to have higher levels in the prostate gland compared to other tissues. Elevated levels of acid phosphatase can indicate prostate cancer.

5. **Conclusion**: Based on the analysis, the most commonly used marker enzyme in the clinical diagnosis of prostate cancer is **Acid Phosphatase** (Option D).

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