Virus causing hepatocellular carcinoma, belongs to ?
**Core Concept**
The question is testing the student's knowledge of the etiology of hepatocellular carcinoma (HCC), a common type of liver cancer. Hepatocellular carcinoma is a multifactorial disease, with chronic infection with certain viruses being a major risk factor.
**Why the Correct Answer is Right**
The correct answer is HBV (Hepatitis B virus). HBV infection is a well-established cause of HCC, particularly in regions with high prevalence of the virus. Chronic HBV infection leads to integration of HBV DNA into the host genome, resulting in viral oncogenes that promote liver cell proliferation and malignant transformation. The HBV X protein (HBx) plays a crucial role in this process by interacting with p53 and other cellular proteins to disrupt normal cell cycle regulation.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Hepatitis C virus (HCV) is also a major risk factor for HCC, but it is not the primary cause being tested in this question. HCV infection can also lead to chronic liver disease and HCC, but the pathogenesis is different from HBV.
**Option B:** This option is incorrect because Hepatitis D virus (HDV) is a satellite virus that requires HBV for replication. While HDV infection can exacerbate liver disease in individuals with HBV, it is not a primary cause of HCC.
**Option C:** This option is incorrect because Hepatitis E virus (HEV) is primarily a cause of acute hepatitis and is not associated with chronic liver disease or HCC.
**Clinical Pearl / High-Yield Fact**
HBV vaccination is a critical public health measure to prevent HCC, particularly in regions with high prevalence of the virus. The World Health Organization recommends universal HBV vaccination for all infants at birth to prevent chronic HBV infection and its complications, including HCC.
**Correct Answer:** D. Hepatitis B virus.