Objective: To investigate the spectrum of PIK3CA gene mutations in Chinese women with hormone receptor positive and HER2 negative (HR⁺/HER2^-) breast cancer, to provide the genetic evidence for identifying potential beneficiaries from specific PI3K isoform inhibitors in Chinese women with breast cancer and to develop detection strategies. Methods: A total of 365 breast cancer specimens archived at the Peking Union Medical College Hospital, Beijing, China from January 2017 to October 2017 were screened. Among these patients, 186 HR⁺/HER2^- women with invasive breast cancer were collected. PIK3CA gene mutations were detected using next generation sequencing technology. The gene variant features were then analyzed and compared with reported data. Results: Among the 186 HR⁺/HER2^- breast cancer cases, 40 (21.5%,40/186) cases harbored PIK3CA gene mutations. Exons 9 and 20 of PIK3CA mutations occurred in 92.5%(37/40)of the tumors, which included E545K, E545G, Q546K, E542K, Q546R, P539R, E547D, H1047R, H1047L, H1047Q and N1044Y. Only one case harbored the exon 7 C420R mutation. Additionally, exons 1 (F83C) and 5 (G364R) uncommon mutations were discovered respectively in 2 cases. Based on the finding, 85.0% (34/40) of cases with known mutations could be detected using companion diagnostic methods. Moreover, 25.0% (10/40) of patients had two or three variants, which were composed of E726K/N345K, H1047Q/N345K, H1047R/G364R, H1047R/E453K, E545G/E726K, E542K/E726K, E542K/H1047R, E545K/H1047R/H1047L and E545K/E547D. The lymph node positive rate in these patients with PIK3CA mutation was remarkably higher than those without (i.e., wild type, <i>Pi><0.05). Conclusions: In this group of HR⁺/HER2^- breast cancer patients, common PIK3CA gene mutations account for the vast majority of the mutations. New rare variants in PIK3CA are also identified while their clinical significance needs to be further studied in a large cohort and/or multi-center study.
Humans ; Female ; Breast Neoplasms/genetics* ; East Asian People ; China ; Class I Phosphatidylinositol 3-Kinases/genetics*

Child ; Humans ; Class I Phosphatidylinositol 3-Kinases/genetics* ; Mutation ; Neoplasms, Germ Cell and Embryonal/genetics*

OBJECTIVETo investigate the effect of PIK3CA/siRNA chitosan nanoparticle on the invasiveness of gastric carcinoma and the potential value of PIK3CA/siRNA chitosan nanoparticle in suppressing the metastasis of gastric carcinoma.

METHODSGastric cancer cells were treated with PIK3CA/siRNA nanoparticle (with a diameter of 350 nm), and the efficiency of PIK3CA gene interference was evaluated using Western blotting and real-time PCR. The changes of the invasive capacity of the treated cells was assessed with Transwell assay.

RESULTSPIK3CA/siRNA chitosan nanoparticle efficiently lowered the expression level of PIK3CA and significantly decreased the invasion of BGC823 cells.

CONCLUSIONPIK3CA gene interference mediated by PIK3CA/siRNA chitosan nanoparticle can decrease the invasive capacity of gastric cancer cells in vitro.

Cell Line, Tumor ; Cell Proliferation ; Chitosan ; Class I Phosphatidylinositol 3-Kinases ; Humans ; Nanoparticles ; Phosphatidylinositol 3-Kinases ; genetics ; RNA, Small Interfering ; Real-Time Polymerase Chain Reaction ; Stomach Neoplasms ; pathology

OBJECTIVETo investigate PIK3CA, PTEN status in the primary lesion of colorectal cancer (CRC): relationship with occurrences of liver metastasis and its prognosis.

METHODSPatients with CRC who had the primary tumor resected between 2003 and 2008 were selected and enrolled into three groups according to the occurrence of liver metastasis. The mutations of PIK3CA exon 9 and 20, PTEN exon 5, 7, 8 in primary cancer cells in formalin-fixed, paraffin-embedded specimens were detected by Pyrosequencing, then a statistical analysis was deduced to find out the relationship between PIK3CA, PTEN status and occurrences of liver metastasis as well as the prognosis.

RESULTSOf all the 300 CRC cases, the mutation rates of PIK3CA and PTEN was 18.2% (51/300) and 16.3% (49/300). The multivariate Logistic analysis revealed that exon 5 mutation of PTEN was one of the independent risk factors of occurrence of metachronous liver metastasis in CRC patients (HR = 1.634, 95%CI: 1.796 - 3.355, P = 0.041). Patients with PTEN mutation had a poorer overall survival in group with synchronous liver metastasis (median survival time 62.0 months vs 71.0 months, χ(2) = 12.942, P = 0.048) while CRC patients who had the liver metastasis resected in group of synchronous and metachronous liver metastasis had a poorer disease free survival rates with PIK3CA mutation (median survival time 16.0 months vs 25.0 months, χ(2) = 9.679, P = 0.037).

CONCLUSIONSThe exon 5 mutation of PTEN of CRC is potentially correlated with the occurrence of synchronous liver metastasis. CRC patients who had the liver metatasis resected but with PIK3CA mutation could have a poorer prognosis.

Aged ; Class I Phosphatidylinositol 3-Kinases ; Colorectal Neoplasms ; genetics ; pathology ; Female ; Humans ; Liver Neoplasms ; genetics ; secondary ; Male ; Middle Aged ; Mutation ; PTEN Phosphohydrolase ; genetics ; Phosphatidylinositol 3-Kinases ; genetics ; Prognosis ; Proto-Oncogene Proteins B-raf ; genetics ; Survival Analysis

OBJECTIVETo investigate the expression and mutation of PIK3CA gene in hepatocellular carcinomas (HCC).

METHODSHCC samples and the corresponding adjacent tissues were collected from the surgical patients with pathologically verified diagnosis. The exons 1, 9 and 20 of PIK3CA gene were detected by PCR-SSCP and DNA sequencing. Immnohistochemistry was employed to test the expression of PIK3CA gene in these samples.

RESULTSNo mutation was found in exons 1, 9 or 20 of PIK3CA gene in the HCC tissue and the adjacent tissues by PCR-SSCP and DNA sequencing, while abnormal superimposed peaks were found on the sequence map of exon 9 in 25 cases of HCC tissue. Immunohistochemistry showed that expression of PIK3CA was higher in the HCC tissue than in the corresponding adjacent tissue (50.81% vs 14.75%).

CONCLUSIONPIK3CA gene mutation may exist in HCC in Guangxi, which can be associated with the development of HCC, but the ratio of hotspot mutations is low.

Base Sequence ; Carcinoma, Hepatocellular ; genetics ; Class I Phosphatidylinositol 3-Kinases ; Exons ; genetics ; Female ; Humans ; Liver Neoplasms ; genetics ; Male ; Middle Aged ; Molecular Sequence Data ; Mutation ; Phosphatidylinositol 3-Kinases ; genetics ; metabolism ; Sequence Analysis, DNA

The phosphatidylinositol-3 kinase(PI3K) pathway regulates a number of cellular processes, including cell survival, cell growth, and cell cycle progression. Consequently, this pathway is commonly deregulated in cancer. In particular, mutations in the gene PIK3CA that encodes the p110α catalytic subunit of the PI3K enzymes result in cell proliferation and resistance to apoptosis in vitro and induce breast tumors in transgenic mice. These data underscore the role of this pathway during oncogenesis. Thus, an ongoing, large-scale effort is underway to develop clinically active drugs that target elements of the PI3K pathway. However, conflicting data suggest that gain-of-function PIK3CA mutations may be associated with either a favorable or a poor clinical outcome, compared with the wild-type PIK3CA gene. In the current study, we performed a systematic review of breast cancer clinical studies. Upon evaluation of 2587 breast cancer cases from 12 independent studies, we showed that patients with tumors harboring a PIK3CA mutation have a better clinical outcome than those with a wild-type PIK3CA gene. Importantly, this improved prognosis may pertain only to patients with mutations in the kinase domain of p110α and to postmenopausal women with estrogen receptor-positive breast cancer. We propose three potential explanations for this paradoxical observation. First, PIK3CA mutations may interfere with the metastasis process or may induce senescence, which results in a better outcome for patients with mutated tumors. Secondly, we speculate that PIK3CA mutations may increase early tumor diagnosis by modification of the actin cytoskeleton in tumor cells. Lastly, we propose that PIK3CA mutations may be a favorable predictive factor for response to hormonal therapy, giving a therapeutic advantage to these patients. Ultimately, an improved understanding of the clinical impact of PIK3CA mutations is critical for the development of optimally personalized therapeutics against breast cancer and other solid tumors. This effort will be important to prevent or explain therapeutic failures and select patients who are most likely to respond to new therapies that inhibit the PI3K pathway.
Antineoplastic Agents, Hormonal ; therapeutic use ; Apoptosis ; Breast Neoplasms ; drug therapy ; genetics ; metabolism ; pathology ; Cellular Senescence ; Class I Phosphatidylinositol 3-Kinases ; Disease-Free Survival ; Early Detection of Cancer ; Female ; Humans ; Mutation ; Neoplasm Metastasis ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; genetics ; metabolism ; Survival Rate

The present study aimed to explore the underlying mechanism of Wuling Capsules in the treatment of hepatic fibrosis(HF) through network pharmacology, molecular docking, and animal experiments. Firstly, the chemical components and targets of Wuling Capsules against HF were searched from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP), Traditional Chinese Medicines Integrated Database(TCMID), GeneCards, and literature retrieval. The protein-protein interaction(PPI) network analysis was carried out on the common targets by STRING database and Cytoscape 3.9.1 software, and the core targets were screened, followed by Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analyses. Enrichment analysis was conducted on the core targets and the "drug-core component-target-pathway-disease" network was further constructed. Subsequently, molecular docking between core components and core targets was conducted using AutoDock Vina software to predict the underlying mechanism of action against HF. Finally, an HF model induced by CCl_4 was constructed in rats, and the general signs and liver tissue morphology were observed. HE and Masson staining were used to analyze the liver tissue sections. The effects of Wuling Capsules on the levels of inflammatory factors, hydroxyproline(HYP) levels, and core targets were analyzed by ELISA, RT-PCR, etc. A total of 445 chemical components of Wuling Capsules were screened, corresponding to 3 882 potential targets, intersecting with 1 240 targets of HF, and 47 core targets such as TNF, IL6, INS, and PIK3CA were screened. GO and KEGG enrichment analysis showed that the core targets mainly affected the process of cell stimulation response and metabolic regulation, involving cancer, PI3K-Akt, MAPK, and other signaling pathways. Molecular docking showed that the core components of Wuling Capsules, such as lucidenic acid K, ganoderic acid B, lucidenic acid N, saikosaponin Q2, and neocryptotanshinone, had high affinities with the core targets, such as TNF, IL6 and PIK3CA. Animal experiments showed that Wuling Capsules could reduce fat vacuole, inflammatory infiltration, and collagen deposition in rat liver, decrease the levels of inflammatory cytokines TNF-α, IL-6, and HYP, and downregulated the expressions of PI3K and Akt mRNA. This study suggests that the anti-HF effect of Wuling Capsules may be achieved by regulating the PI3K-Akt signaling pathway, reducing the levels of TNF-α and IL-6 inflammatory factors, and inhibiting the excessive deposition of collagen.
Animals ; Rats ; Interleukin-6 ; Network Pharmacology ; Animal Experimentation ; Tumor Necrosis Factor-alpha ; Molecular Docking Simulation ; Phosphatidylinositol 3-Kinases ; Proto-Oncogene Proteins c-akt ; Liver Cirrhosis/genetics* ; Medicine, Chinese Traditional ; Capsules ; Class I Phosphatidylinositol 3-Kinases ; Collagen ; Drugs, Chinese Herbal/pharmacology*

Breast Diseases ; diagnostic imaging ; metabolism ; Breast Neoplasms ; diagnostic imaging ; metabolism ; Class I Phosphatidylinositol 3-Kinases ; genetics ; Female ; Humans ; Middle Aged ; Point Mutation

Rapamycin and its derivatives (rapalogs), a group of allosteric inhibitors of mammalian target of rapamycin (mTOR), have been actively tested in a variety of cancer clinical trials, and some have been approved by the Food and Drug Administration for the treatment of certain types of cancers. However, the single agent activity of these compounds in many tumor types remains modest. The mTOR axis is regulated by multiple upstream signaling pathways. Because the genes (e.g., PIK3CA, KRAS, PTEN, and LKB1) that encode key components in these signaling pathways are frequently mutated in human cancers, a subset of cancer types may be addicted to a given mutation, leading to hyperactivation of the mTOR axis. Thus, efforts have been made to demonstrate the potential impact of genetic alterations on rapalog-based or mTOR-targeted cancer therapy. This review will primarily summarize research advances in this direction.
Antibiotics, Antineoplastic ; therapeutic use ; Cell Line, Tumor ; Class I Phosphatidylinositol 3-Kinases ; Humans ; Mutation ; Neoplasms ; drug therapy ; metabolism ; PTEN Phosphohydrolase ; genetics ; metabolism ; Phosphatidylinositol 3-Kinases ; genetics ; metabolism ; Protein-Serine-Threonine Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins ; genetics ; metabolism ; Proto-Oncogene Proteins p21(ras) ; Signal Transduction ; Sirolimus ; analogs & derivatives ; therapeutic use ; TOR Serine-Threonine Kinases ; antagonists & inhibitors ; metabolism ; ras Proteins ; genetics ; metabolism

BACKGROUNDThe addition of anti-human epidermal growth factor receptor 2 (HER2)-targeted drugs, such as trastuzumab, lapatinib, and trastuzumab emtansine (T-DM1), to chemotherapy significantly improved prognosis of HER2-positive breast cancer patients. However, it was confused that metastatic patients vary in the response of targeted drug. Therefore, methods of accurately predicting drug response were really needed. To overcome the spatial and temporal limitations of biopsies, we aimed to develop a more sensitive and less invasive method of detecting mutations associated with anti-HER2 therapeutic response through circulating-free DNA (cfDNA).

METHODSFrom March 6, 2014 to December 10, 2014, 24 plasma samples from 20 patients with HER2-positive metastatic breast cancer who received systemic therapy were eligible. We used a panel for detection of hot-spot mutations from 50 oncogenes and tumor suppressor genes, and then used targeted next-generation sequencing (NGS) to identify somatic mutation of these samples in those 50 genes. Samples taken before their first trastuzumab administration and subsequently proven with clinical benefit were grouped into sensitive group. The others were collected after disease progression of the trastuzumab-based therapy and were grouped into the resistant group.

RESULTSA total of 486 single-nucleotide variants from 46 genes were detected. Of these 46 genes, phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), proto-oncogene c-Kit (KIT), and tumor protein p53 (TP53) were the most common mutated genes. Seven genes, including epidermal growth factor receptor (EGFR), G protein subunit alpha S (GNAS), HRas proto-oncogene (HRAS), mutL homolog 1 (MLH1), cadherin 1 (CDH1), neuroblastoma RAS viral oncogene homolog (NRAS), and NOTCH1, that only occurred m utations in the resistant group were associated with the resistance of targeted therapy. In addition, we detected a HER2 S855I mutation in two patients who had persistent benefits from anti-HER2 therapy.

CONCLUSIONTargeted NGS of cfDNA has potential clinical utility to detect biomarkers from HER2-targeted therapies.

Adolescent ; Adult ; Aged ; Biomarkers, Tumor ; genetics ; Breast Neoplasms ; genetics ; metabolism ; Cadherins ; genetics ; Chromogranins ; genetics ; Class I Phosphatidylinositol 3-Kinases ; Drug Resistance, Neoplasm ; genetics ; Female ; GTP-Binding Protein alpha Subunits, Gs ; genetics ; Humans ; Male ; Middle Aged ; Mutation ; genetics ; Phosphatidylinositol 3-Kinases ; genetics ; Proto-Oncogene Proteins c-kit ; genetics ; Receptor, ErbB-2 ; metabolism ; Receptor, Notch1 ; genetics ; Tumor Suppressor Protein p53 ; genetics ; Young Adult