Linfu Zhou

DNA methylation is of paramount importance for the evolution of human cancers. Its high sensitivity and specificity make it a potential biomarker for early cancer screening in the context of an inc... Lay abstract In the context of an increasing global burden of gastrointestinal (GI) carcinoma, early cancer screening is of paramount importance, so there is an urgent need for efficient and reliab...

In China, there is a high prevalence of antibiotic-resistant Helicobacter pylori infections in the population. The aim of the study was to assess a new ARMS-PCR test for detection of H. pylori clarithromycin resistance (CR) and quinolone resistance (QR) mutations and evaluate the spectrum of antibiotic resistance in patients from three Chinese provinces. Sanger sequencing and multiplex ARMS-PCR were used to detect H. pylori CR and QR bacteria in gastric biopsy samples. Among the 1,182 patients enrolled with gastritis, 643 (54.4%) were positive for H. pylori. Of these, 371 (57.7%) had antibiotic-resistant strains, comprising 236 (63.6%) with a single drug antibiotic-resistant strain and 135 (36.4%) with multiple drug-resistant strains. Following Sanger sequencing analysis of 23S rRNA and gyrA gene for mutations (antibiotic resistance markers), rates of CR, QR, and multidrug resistance (CR and QR) were 19.9, 12.0, and 25.8%, respectively. The 23S rRNA CR mutation A2143G (286, 96.9%) and the gyrA QR mutations C261A (85, 31.5%) and G271A (71, 26.3%) were common. Benchmarking against Sanger sequencing results, multiplex ARMS-PCR test had a high diagnostic sensitivity and specificity for detection of CR (96 and 93%), QR (95 and 92%) and multidrug resistance (95 and 95%). Based on our findings, the high incidence of single and multiple antibiotic resistance requires the routine checking of antibiotic resistance in all patients with suspected H. pylori infections. Multiplex ARMS-PCR is a simple and rapid test that can be now used for more efficient treatment of H. pylori infections and reduces the misuse of antibiotics.

Golgi phosphoprotein 73 (GP73), encoded by GOLM1, is a highly expressed factor in hepatocellular carcinoma (HCC) cells and has been regarded for several years as a remarkable serum biomarker for the diagnosis of HCC. Recently, it was found that upregulation of GP73 promotes cancer metastasis, but the mechanism is complex, and it is even unclear how the gene is transactivated in HCC cells. In this study, it was discovered that c-Myc transactivated GP73 in a mildly hypoxic microenvironment and that the activation of c-Myc upregulated the expression of matrix metalloproteinase-7 (MMP-7). Moreover, it is shown that GP73 interacted with intracellular MMP-7 in the region of the cytoplasmic domain and facilitated the trafficking and secretion of MMP-7, resulting in cell metastasis. This study indicates that GP73 is transactivated by c-Myc and serves as a transporter in the trafficking of intracellular MMP-7 in HCC cells. These findings suggest that GP73 is a potential target for combating metastatic HCC.

Golgi phosphoprotein 73 (GP73) has been regarded as a novel serum biomarker for the diagnosis of hepatocellular carcinoma (HCC) in recent years. It has been reported that the upregulation of GP73 may promote the carcinogenesis and metastasis of HCC; however, the mechanisms remain poorly understood. In this study, GP73 correlates positively with matrix metalloproteinase‐2 (MMP‐2) in HCC‐related cells and tissues. Further studies indicate that the knockdown of GP73 blocks MMP‐2 trafficking and secretion, resulting in cell invasion inhibition. Additionally, the knockdown of GP73 induces the accumulation of intracellular MMP‐2, which inhibits the phosphorylation of Src at Y416 and triggers the inhibition of SAPK/JNK and p53‐p21 signalling pathways through a negative feedback loop. Finally, the transactivation of MMP2 was inhibited by the reduction in E2F1. This study reveals that GP73 plays functional roles in the trafficking and equilibrium of epithelial‐mesenchymal transition (EMT)‐related secretory proteins and that GP73 serves as a new potential target for combating the metastasis of HCC.

For decades, E2F1 has been recognized as a retinoblastoma protein (RB) binding transcription factor that regulates the cell cycle. E2F1 binds preferentially to RB and accelerates the cell cycle in most cancer cells. However, it is thought that E2F1 modulates cell proliferation in other ways as well. Herein, it has been discovered that in pathological tissues derived from hepatocellular carcinoma (HCC) patients, E2F1 correlates positively with IQGAP3 and that both of these factors are highly expressed (N = 164, R = 0.6716). In addition, a high level of E2F1 or IQGAP3 predicted poor survival in HCC patients. Further study determined that E2F1 transactivates IQGAP3, the GTPase binding protein in MHCC-97H cells. Co-immunoprecipitation analysis indicated that IQGAP3 interacts with PKC delta and competitively inhibits the interaction between PKC delta and PKC alpha, resulting in phosphorylation of PKC alpha activation and promotion of cell proliferation. This study reveals that highly expressed E2F1 not only transactivates cell-cycle-related factors but also promotes HCC proliferation by activating the phosphorylation of PKC alpha.

Synchronous multifocal tumors are common in the hepatobiliary and pancreatic system but because of similarities in their histological features, oncologists have difficulty in identifying their precise tissue clonal origin through routine histopathological methods. To address this problem and assist in more precise diagnosis, we developed a computational approach for tissue origin diagnosis based on naive Bayes algorithm (TOD‐Bayes) using ubiquitous RNA‐Seq data. Massive tissue‐specific RNA‐Seq data sets were first obtained from The Cancer Genome Atlas (TCGA) and ∼1,000 feature genes were used to train and validate the TOD‐Bayes algorithm. The accuracy of the model was >95% based on tenfold cross validation by the data from TCGA. A total of 18 clinical cancer samples (including six negative controls) with definitive tissue origin were subsequently used for external validation and 17 of the 18 samples were classified correctly in our study (94.4%). Furthermore, we included as cases studies seven tumor samples, taken from two individuals who suffered from synchronous multifocal tumors across tissues, where the efforts to make a definitive primary cancer diagnosis by traditional diagnostic methods had failed. Using our TOD‐Bayes analysis, the two clinical test cases were successfully diagnosed as pancreatic cancer (PC) and cholangiocarcinoma (CC), respectively, in agreement with their clinical outcomes. Based on our findings, we believe that the TOD‐Bayes algorithm is a powerful novel methodology to accurately identify the tissue origin of synchronous multifocal tumors of unknown primary cancers using RNA‐Seq data and an important step toward more precision‐based medicine in cancer diagnosis and treatment.

Knockdown of golgi phosphoprotein 2 inhibits hepatocellular carcinoma cell proliferation and motility

Autophagy refers to a lysosomal degradative pathway or a process of self-cannibalization. This pathway maintains nutrients levels for vital cellular functions during periods of starvation and it provides cells with survival advantages under various stress situations. However, the mechanisms responsible for the induction and regulation of autophagy are poorly understood. The c-Jun NH2-terminal kinase (JNK) signal transduction pathway functions to induce defence mechanisms that protect organisms against acute oxidative and xenobiotic insults. This pathway has also been repeatedly linked to the molecular events involved in autophagy regulation. The present review will focus on recent advances in understanding of the relationship between mitogen-activated protein kinase (MAPK)/JNK signalling and autophagic cell death.

The purpose of the present work was to develop a novel, long-acting and potent human serum albumin/granulocyte colony stimulating factor (HSA/G-CSF) therapeutic fusion protein. The novel fusion protein, called HMG, was constructed by genetically fusing mutated human derived G-CSF (mG-CSF) to the C-terminal of HSA and then prepared in Pichia pastoris. The molecular mass of HMG was about 85 kDa and the isoelectric point was 5.3. Circular dichroism spectroscopy suggested that mG-CSF retained nearly all of its native secondary structure, regardless of fusion. The binding capabilities of mG-CSF moiety to G-CSF receptor and HSA moiety to warfarin showed very little change after fusing. The bioactivity of HMG (11.0×10⁶ IU/mg) was more than twice that of rHSA/G-CSF (4.6×10⁶ IU/mg). A mutation was made at the 718^th amino acid of HMG, substituting Ala for Thr, to investigate the glycosylation of HMG expressed in P. pastoris. Data indicated that HMG was modified at Thr718, speculatively with the addition of a mannose chain. In conclusion, a novel HSA/G-CSF fusion protein was successfully constructed based on a mutated G-CSF. This protein showed more potent bioactivity than rHSA/G-CSF and thus may be a suitable long-acting G-CSF.