HPV discovery raises hope for new cervical cancer treatments. Researchers at the University of Virginia (UVA) School of Medicine have made a discovery about human papillomavirus (HPV) that could lead to new treatments for cervical cancer and other cancers caused by the virus.
HPV is responsible for nearly all cases of cervical cancer and 95 percent of anal cancers. It is the most common sexually transmitted disease, infecting more than 79 million Americans. Most have no idea that are infected or that they could be spreading it.
HPV has been a stubborn foe for scientists, even though researchers have a solid grasp of how it causes cancer: by producing proteins that shut down healthy cells’ natural ability to prevent tumors. Blocking one of those proteins, called oncoprotein E6, seemed like an obvious solution, but decades of attempts to do so have proved unsuccessful.
UVA researcher Anindya Dutta, PhD, of the UVA Cancer Center and his colleagues, however, have found a new way forward. They have determined that the virus takes the help of a protein present in our cells, an enzyme called USP46, which becomes essential for HPV-induced tumor formation and growth. And USP46 enzyme promises to be very susceptible to drugs.
“It’s an enzyme, and because it’s an enzyme, it has a small pocket essential for its activity, and because drug companies are very good at producing small chemicals that will jam that pocket and make enzymes like USP46 inactive,” said Dutta. “So, we are very excited by this possibility that by inactivating USP46 we’ll have a way to treat HPV-caused cancers.”
Curiously, HPV uses USP46 for an activity that is opposite to what the oncoprotein E6 was known to do. E6 has been known for more than two decades to recruit another cellular enzyme to degrade the cell’s tumor suppressor, while Dutta’s new finding shows that E6 uses USP46 to stabilize other cellular proteins and prevent them from being degraded. Both activities of E6 are critical to the growth of cancer.
The researchers note that enzyme USP46 is specific to HPV strains that cause cancer. It is not used by other strains of HPV that do not cause cancer, they report.
UDT
Urine drug testing may be important in early phases of addiction treatment. A new study performed by Boston Medical Center and faculty at the Boston University School of Medicine shows that urine drug testing (UDT) can be a useful tool to treat patients with opioid use disorder in a primary care setting.
The analysis revealed that patients are less likely to disclose drug use earlier in treatment, and although the study was not able to identify reasons for this, the authors believe that it may be related to fear of discharge from a treatment program and stigma related to relapse.
Published in Drug and Alcohol Dependence, the study indicates the need to develop interventions for patients who have positive UDTs urine drug tests in order to keep them engaged in care.
The researchers correlated the frequency of patients’ self-reported substance use and the results of their UDTs. It showed that 76 percent of UDTs positive for cocaine and 57 percent of those positive for opioids occurred when patients did not disclose substance use in their treatment visit. Additionally, rates of positive UDTs without self-reported substance use were higher earlier in treatment, possibly reflecting growing trust between the patient and the treatment team over time.
Overall, the study reinforces the current guidelines that call for using UDTs to monitor for substance use in office-based addiction treatment but encourage less frequent testing as patients become stable in their recovery.
Correction
Regarding the January 2019 CE Test, page 10: question number 16 was printed incorrectly. The correct version is now available at https://www.mlo-online.com/wp-content/uploads/2018/12/MLO201901CEtest.pdf. We apologize for the error.
