Structure, function, and inhibitor targeting of HIV-1 Nef-effector kinase complexes
JOURNAL OF BIOLOGICAL CHEMISTRY
Authors: Staudt, Ryan P.; Alvarado, John J.; Emert-Sedlak, Lori A.; Shi, Haibin; Shu, Sherry T.; Wales, Thomas E.; Engen, John R.; Smithgall, Thomas E.
Abstract
Antiretroviral therapy has revolutionized the treatment of AIDS, turning a deadly disease into a manageable chronic condition. Life-long treatment is required because existing drugs do not eradicate HIV-infected cells. The emergence of drug-resistant viral strains and uncertain vaccine prospects highlight the pressing need for new therapeutic approaches with the potential to clear the virus. The HIV-1 accessory protein Nef is essential for viral pathogenesis, making it a promising target for antiretroviral drug discovery. Nef enhances viral replication and promotes immune escape of HIV-infected cells but lacks intrinsic enzymatic activity. Instead, Nef works through diverse interactions with host cell proteins primarily related to kinase signaling pathways and endosomal trafficking. This review emphasizes the structure, function, and biological relevance of Nef interactions with host cell protein-tyrosine kinases in the broader context of Nef functions related to enhancement of the viral life cycle and immune escape. Drug discovery targeting Nef-mediated kinase activation has allowed identification of promising inhibitors of multiple Nef functions. Pharmacological inhibitors of Nef-induced MHC-I down-regulation restore the adaptive immune response to HIV-infected cells in vitro and have the potential to enhance immune recognition of latent viral reservoirs as part of a strategy for HIV clearance.
Neoadjuvant Pyrotinib plus Trastuzumab and Chemotherapy for Stage I-III HER2-PositiveBreast Cancer: A PhaseIIClinical Trial
ONCOLOGIST
Authors: Xuhong, Juncheng; Qi, Xiaowei; Tang, Peng; Fan, Linjun; Chen, Li; Zhang, Fan; Tan, Xuanni; Yan, Wenting; Zhong, Ling; He, Cheng; Liang, Yan; Ren, Lin; Wang, Minghao; Zhang, Yi; Jiang, Jun
Abstract
Lessons Learned This is the first trial to explore the neoadjuvant therapy of pyrotinib in HER2-positive operable and locally advanced breast cancer, in combination with epirubicin plus cyclophosphamide followed by docetaxel plus trastuzumab. Results primarily showed that pyrotinib in combination with epirubicin plus cyclophosphamide followed by docetaxel plus trastuzumab was effective and safe in HER2-positive operable and locally advanced breast cancer. A subsequent randomized controlled trial is still warranted to confirm these results. Background The efficacy and safety of neoadjuvant therapy of pyrotinib, a new irreversible tyrosine kinase inhibitor (TKI), was first estimated in patients with HER2-positive breast cancer in this phase II study, in combination with trastuzumab and chemotherapy. Methods Between February 19, 2019, and November 20, 2019, 20 female Chinese patients with stage I-III HER2-positive breast cancer were assigned to receive eight cycles of neoadjuvant pyrotinib (P) in combination with four cycles of epirubicin (E) and cyclophosphamide (C) followed by four cycles of docetaxel (T) and trastuzumab (H), once every 3 weeks, referred to as P + EC-TH. Results A total of 19 patients completed the therapy and final surgery. The total pathological complete response (tpCR) rate was 73.7% (95% confidence interval [CI], 48.8-90.9), and no recurrence or metastasis occurred during the short-term follow-up period. The objective response rate (ORR) was 100% (95% CI, 82.4-100). The most common adverse events (AEs) were diarrhea and leukopenia in 18 of 20 patients (90%), but no grade 5 AEs were reported. Conclusion This study showed that in HER2-positive operable or locally advanced breast cancer, the tpCR rate of P + EC-TH neoadjuvant therapy was about twice as high as that of EC-TH neoadjuvant therapy reported in other trials, with tolerable side effects.