Inhibition of the AKT1/mTOR pathway through SIRT6 over expression downregulated the expression of programmed death-ligand 1 and prolonged overall survival in lung adenocarcinoma.

Background: Programmed death-ligand 1 (PD-L1) is a common biomarker of immune checkpoint inhibitors (ICIs). The purpose of our study was to investigate the relationship between Sirtuin 6 (SIRT6) and PD-L1 expressions in lung adenocarcinoma. Methods: Recombinant plasmids containing green fluorescent protein (GFP)/no SIRT6 (h-NULL) and GFP/SIRT6 (h-SIRT6) were constructed and transfected into A549 cells by lentivirus as vector. The experiment was divided into control, h-NULL and h-SIRT6 groups. We detected apoptosis and the cell cycle by flow cytometry and observed migration and proliferation by wound-healing assays and methyl thiazolyl tetrazolium. The expressions of SIRT6, PD-L1, serine/threonine protein kinase-1 (AKT1), mammalian target of rapamycin (mTOR), B-cell lymphoma-2 (BCL-2) associated X protein (BAX), and BCL-2 were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot. We retrospectively analyzed the relationship between SIRT6 expression and survival in lung adenocarcinoma treated by ICIs. Results: The expression of BAX, apoptosis rate, and proportion of G0G1 and G2M phases in the h-SIRT6 group were higher than in the control and h-NULL groups (P<0.05). The expressions of PD-L1, BCL-2, AKT1, and mTOR migration and proliferation rates and proportion of S phase in the h-SIRT6 group were lower than in the control and h-NULL groups (P<0.05). Survival in lung adenocarcinoma with high SIRT6 expression was better than with low SIRT6 expression. Conclusions: SIRT6 over expression, through the inhibition of the AKT1/mTOR pathway, down-regulated PD-L1 expression, influenced biological behaviors, and prolonged survival of lung adenocarcinoma. SIRT6 expression may be a potential gene biomarker for immunotherapy in lung adenocarcinoma.

Apatinib enhances the antitumor effects of radiation in HeLa cell line mouse model of invasive cervical cancer.

Background: There is the lack of reports on apatinib (APA) combined with radiation in the treatment of cervical cancer. The aim of our study was to investigate the anti-tumor effect of APA combined with radiation using an in vivo model of cervical cancer. Methods: The mouse models, established using Henrietta Lacks (HeLa) cells, were randomly divided into 4 groups: the control group, radiotherapy (RT) alone group, cisplatin (DDPs) combination RT group (DDPs + RT), and APA combination RT group (APA + RT). The expressions of the vascular endothelial growth factor receptor-2 (VEGFR-2), platelet endothelial cell adhesion molecule-1 (CD31), proliferating cell nuclear antigen (Ki-67), and histone H2AX family member (γ-H2AX) were determined using immunohistochemistry (IHC), the extent of apoptosis was determined using terminal deoxynucleotidyl transferase (TdT)-mediated (dUTP) nick-end labeling (TUNEL), and tumor metabolism was determined using micro18F-fluorodexyglucose positron emission tomography/computed tomography. The length of survival was observed and recorded. Results: The positive expressions of VEGFR-2, CD31, and Ki-67 in the APA + RT group were obviously reduced compared with the control, RT, and DDPs + RT groups (P<0.05). The positive expression of γ-H2AX was obviously increased compared with the control and RT groups (P<0.05), whereas the apoptosis rate in the APA + RT group was obviously increased compared with the control, RT, and DDPs + RT groups (P<0.05). The tumor metabolism and volume in the APA + RT group were obviously reduced compared with the control, RT, and DDPs + RT groups. The length of survival was prolonged by 22 and 11 days in the APA + RT group compared with the RT and DDPs + RT groups, respectively (P<0.05). Conclusions: The combination of APA and RT could significantly enhance the anti-tumor efficacy of RT and prolong the median survival in a mouse model of cervical cancer.

Novel composite drug delivery system as a novel radio sensitizer for the local treatment of cervical carcinoma.

In this study, we investigated in vivo radiosensitizing effects of a gel-based dual drug delivery system (DDS) (PECE/DDP + mPEG-PCL/PTX, or PDMP) in a cervical cancer model, and determined its possible mechanisms of action. A xenograft cervical cancer model was used to investigate the radio sensitization effect of PDMP. Mice underwent paclitaxel (PTX) + cisplatin (DDP), PECE, or PDMP treatment followed by single radiation doses ranging from 0 Gy to 20 Gy. Radio sensitization was analyzed by tumor regrowth delay (TGD). The sensitization enhancement ratio (SER) was calculated by the doses needed to yield TGD when using radiation treatment alone and when using radiation plus drug treatment. The impact of irradiation and drugs on TGD was determined, and an optimum radiation dose was chosen for further evaluation of radio sensitizing effects. The data showed that PDMP yielded the highest radio sensitization (SER was 1.3) and a radiation dose of 12 Gy was chosen for further investigation. PDMP + radiotherapy treatment was most effective in inhibiting tumor growth, prolonging survival time, decreasing expression of CD31, CD133, and aldehyde dehydrogenase 1 (ALDH1), inducing G2/M phase arrest, apoptosis, and expression of Ataxia telangiectasia mutated (ATM) and histone H2AX phosphorylation (γ-H2AX). Thus, our data indicated that PDMP is a promising anti-tumor and radio sensitization reagent for the treatment of cervical carcinoma.

YMDD variants of HBV DNA polymerase gene: rapid detection and clinicopathological analysis with long-term lamivudine therapy after liver transplantation.

AIM: To look for a rapid low-cost technique for the detection of HBV variants. METHODS: Two patients who underwent orthotopic liver transplantation (OLT) for HBV infection were treated with lamivudine (100 mg daily) and HBV infection recurred in the grafted livers. The patients were monitored intensively for liver enzymes, hepatitis B surface antigen (HBsAg) and HBV DNA in serum. Liver biopsy was performed regularly. HBV DNA in a conserved polymerase domain (the YMDD locus) was amplified from serum of each patient by PCR and sequenced. HBV genotypes were analyzed by restriction fragment length polymorphism (RFLP) of the PCR products generated from a fragment of the polymerase gene. RESULTS: YMDD wild-type HBV was detected in one patient by PCR-RFLP and DNA sequencing 19 mo after OLT, and YIDD mutant-type HBV in the other patient, 16 mo after OLT. CONCLUSION: PCR-RFLP assay is an accurate and simple method for genotyping lamivudine-resistant HBV variants.