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

Lung cancer is responsible for 29% of cancer deaths in the United States and has very low 5-year survival rates of approximately 11% in men and 15% in women. Although the early diagnosis of lung cancer may increase the survival rate with adequate treatment, advanced lung cancers are often metastasized and receive limited benefit from therapeutic regimens. As conventional treatments for lung cancer reach their limitations, researchers have attempted to discover novel drug therapies aimed at specific targets contributing to the progression of tumorigenesis. Recent advances in systems biology have enabled the molecular biology of lung carcinogenesis to be elucidated. Our understanding of the physiologic processes of tumor development provide a means to design more effective and specific drugs with less toxicity, thereby accelerating the delivery of new drug therapies to the patient's bedside.
Antineoplastic Agents ; therapeutic use ; Carcinoma, Non-Small-Cell Lung ; drug therapy ; genetics ; metabolism ; Carcinoma, Small Cell ; drug therapy ; genetics ; metabolism ; Drug Delivery Systems ; Humans ; Lung Neoplasms ; drug therapy ; genetics ; metabolism ; Molecular Targeted Therapy ; methods ; Mutation ; Protein Kinase Inhibitors ; therapeutic use ; Proto-Oncogene Proteins ; genetics ; metabolism ; Proto-Oncogene Proteins p21(ras) ; Receptor, Epidermal Growth Factor ; antagonists & inhibitors ; ras Proteins ; genetics ; metabolism

OBJECTIVETo investigate the effect of the selective PI3K inhibitor and MEK inhibitor on KRAS and PTEN co-mutated non-small cell lung cancer cell line NCI-H157 and the relevant mechanisms.

METHODSNCI-H157 was cultured routinely and treated with different concentrations of the two inhibitors. Cell proliferation was detected by MTT cell cycle assay. Based on the MTT results the cells were divided into four groups: the control group, PI3K inhibitor group (GDC-0941, 0.5 and 5.0 µmol/L), combination group I (0.5 µmol/L AZD6244 + 0.5 µmol/L GDC-0941) and combination group II (5.0 µmol/L AZD6244 + 5.0 µmol/L GDC-0941). Colony formation assay was performed to detect colony formation efficiency. The cell cycle and apoptosis were analyzed by flow cytometry. The expression of protein related to apoptosis was tested with Western blot.

RESULTSCell growth was inhibited by the two inhibitors. Combination groups led to stronger cell proliferation inhibition: combination group Ishowed synergistic effect of their actions and combination group II showed an additive effect; in both groups, there were decreased colony number [(77.2 ± 1.54)/well vs (61.50 ± 2.12)/well, P < 0.01] and [(51.00 ± 4.00)/ well vs (22.50 ± 3.53)/well, P < 0.01]; and enhanced apoptotic ratios [(18.30 ± 0.82)% vs (21.32 ± 0.56)%, P < 0.01] and [(27.14 ± 1.58)% vs (42.45 ± 4.42)%, P < 0.01]. In addition, compared to the PI3K inhibitor alone group, the NCI-H157 cells in the combination groups showed increased G0/G1 phase and decreased S phase (P < 0.01). Western blotting showed that the combination groups demonstrated significantly decreased expression of cyclin D1 and cyclin B1, increased p21 and cleaved PARP and decreased bcl-2/bax ratio, compared to the PI3K inhibitor only group.

CONCLUSIONThe combined inhibition of PI3K (AZD6244) and MEK (GDC-0941) has synergistic effects on the proliferation of NCI-H157 cells, but such effects appear to be in a dose-dependent manner.

Apoptosis ; drug effects ; Benzimidazoles ; administration & dosage ; pharmacology ; Carcinoma, Non-Small-Cell Lung ; genetics ; pathology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cyclin B1 ; metabolism ; Cyclin D1 ; metabolism ; Dose-Response Relationship, Drug ; Drug Synergism ; Humans ; Indazoles ; administration & dosage ; pharmacology ; Lung Neoplasms ; genetics ; pathology ; Mitogen-Activated Protein Kinase Kinases ; antagonists & inhibitors ; metabolism ; Mutation ; PTEN Phosphohydrolase ; genetics ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; metabolism ; Poly(ADP-ribose) Polymerases ; metabolism ; Proto-Oncogene Proteins ; genetics ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Proto-Oncogene Proteins p21(ras) ; metabolism ; Signal Transduction ; Sulfonamides ; administration & dosage ; pharmacology ; bcl-2-Associated X Protein ; metabolism ; ras Proteins ; genetics

OBJECTIVETo analyze immunophenotypes and gene mutations of colorectal precancerous lesions and adenocarcinoma, and to compare the difference of carcinogenetic mechanisms between the two precancerous lesions.

METHODSFifty-three cases of colorectal serrated lesions including 30 hyperplastic polyps, 20 sessile serrated adenomas (SSA) and 3 mixed polyps were collected from January 2006 to June 2012.Forty-five cases of traditional adenomas and 50 cases of colorectal adenocarcinomas were also recruited. Thirty hyperplastic polyps, 20 cases of SSA, 3 mixed polyps and 45 traditional adenomas were investigated by immunohistochemistry for the expression of DNA mismatch repair (MMR) proteins (MLH1, MSH2 and MSH6) and DNA methyltransferase MGMT. Mutations of KRAS, BRAF and PIK3CA genes in 10 cases of SSAs, 10 traditional adenomas, 1 mixed polyps and 50 colorectal adenocarcinomas were analyzed by PCR followed by direct Sanger sequencing.

RESULTS(1) Only 3 cases of hyperplastic polyps lost MLH1 expression, and none of SSAs or traditional adenomas showed loss of MLH1. The negative expression rates of MSH2, MSH6 and MGMT in hyperplastic polyps and SSA were significantly higher than those of traditional adenomas. (2) KRAS mutation was found in 5/10 cases of SSAs, 5/10 traditional adenomas and 1/1 mixed polyps. (3) Colorectal adenocarcinomas harbored the mutations of KRAS (48%, 24/50), BRAF (6%, 3/50) and PIK3CA (4%, 2/50).

CONCLUSIONSImmunophenotypic and gene mutation profiles are different between colorectal serrated lesion and traditional adenoma. Alterations of MMR and MGMT expression play important roles in the pathogenesis of "serrated neoplasm". KRAS mutation is a significant genetic change in the early phase of colorectal carcinogenesis.

Adaptor Proteins, Signal Transducing ; metabolism ; Adenocarcinoma ; genetics ; metabolism ; Adenoma ; genetics ; metabolism ; Aged ; Class I Phosphatidylinositol 3-Kinases ; Colonic Polyps ; genetics ; metabolism ; Colorectal Neoplasms ; genetics ; metabolism ; DNA Mismatch Repair ; DNA Modification Methylases ; metabolism ; DNA Repair Enzymes ; metabolism ; DNA, Neoplasm ; metabolism ; DNA-Binding Proteins ; metabolism ; Female ; Humans ; Hyperplasia ; Immunophenotyping ; Male ; Middle Aged ; MutL Protein Homolog 1 ; MutS Homolog 2 Protein ; metabolism ; Nuclear Proteins ; metabolism ; Phosphatidylinositol 3-Kinases ; genetics ; Point Mutation ; Precancerous Conditions ; genetics ; metabolism ; Proto-Oncogene Proteins ; genetics ; Proto-Oncogene Proteins B-raf ; genetics ; Proto-Oncogene Proteins p21(ras) ; Sequence Analysis, DNA ; Tumor Suppressor Proteins ; metabolism ; ras Proteins ; genetics

OBJECTIVETo detect the expression of prostate cancer antigen-1 (PCA-1) in prostate cancer, and to analyze the effects of downregulation of PCA-1 expression on malignant biological behavior of prostate cancer LNCaP cells, and to explore their possible molecular mechanisms.

METHODSPCA-1-siRNA and control siRNA were transfected into LNCaP cells with lipofectamine 2000. The cell cycle, proliferation and migration were determined by methyl thiazolyl tetrazolium (MTT) assay, flow cytometry and Transwell chambers, respectively. Western blotting was used to detect the expression of cyclin E, matrix metallopeptidase 9 (MMP-9) and p21. Immunohistochemistry was used to detect the expression of PCA-1 protein in 126 cases of prostate cancer and 88 cases of benign prostatic hyperplasia (BPH).

RESULTSThe positive rate of PCA-1 expression was 77.8% (98/126) in prostate cancer, and 10.2% (9/88) in BPH, and its expression was not significantly related to age, prostate specific antigen (PSA), Eastern Cooperative Oncology Group (ECOG) score (P > 0.05), and was associated with Gleason score, TNM staging and bone metastasis (P < 0.05). Downregulation of PCA-1 expression inhibited cell proliferation, arrested cell cycle at S phase and decreased cell migration of LNCaP cells. The downregulation of PCA-1 expression decreased the expression of Bcl-xl, cyclin E and MMP-9 proteins, but increased the expression of p21 proteins.

CONCLUSIONSPCA-1 may play an important role in the development of prostate cancer. The downregulation of PCA-1 expression can lead to changes in the proliferation, cell cycle and migration of prostate cancer LNCaP cells, and these effects may be associated with the decrease of Bcl-xl, cyclin E and MMP-9 proteins and increase of p21 protein.

Aged ; Aged, 80 and over ; Antigens, Neoplasm ; genetics ; metabolism ; Cell Cycle ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Cyclin E ; metabolism ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; Humans ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Middle Aged ; Neoplasm Staging ; Oncogene Proteins ; metabolism ; Prostatic Neoplasms ; metabolism ; pathology ; Proto-Oncogene Proteins p21(ras) ; metabolism ; RNA, Small Interfering ; genetics ; Transfection ; bcl-X Protein ; metabolism

Antibodies, Monoclonal ; therapeutic use ; Antibodies, Monoclonal, Humanized ; Antineoplastic Agents ; therapeutic use ; Carcinoma, Non-Small-Cell Lung ; drug therapy ; genetics ; metabolism ; pathology ; Cetuximab ; Gene Rearrangement ; Humans ; Lung Neoplasms ; drug therapy ; genetics ; metabolism ; pathology ; Mutation ; Oncogene Proteins, Fusion ; genetics ; metabolism ; Phosphorylation ; Precision Medicine ; Proto-Oncogene Proteins ; genetics ; metabolism ; Proto-Oncogene Proteins B-raf ; genetics ; metabolism ; Proto-Oncogene Proteins p21(ras) ; Receptor Protein-Tyrosine Kinases ; genetics ; metabolism ; Receptor, Epidermal Growth Factor ; genetics ; metabolism ; ras Proteins ; genetics ; metabolism

NESCA, a newly discovered signaling adapter protein in the NGF-pathway, contains a RUN domain at its N-terminus. Here we report the crystal structure of the NESCA RUN domain determined at 2.0-Å resolution. The overall fold of the NESCA RUN domain comprises nine helices, resembling the RUN domain of RPIPx and the RUN1 domain of Rab6IP1. However, compared to the other RUN domains, the RUN domain of NESCA has significantly different surface electrostatic distributions at the putative GTPase-interacting interface. We demonstrate that the RUN domain of NESCA can bind H-Ras, a downstream signaling molecule of TrkA, with high affinity. Moreover, NESCA RUN can directly interact with TrkA. These results provide new insights into how NESCA participates in the NGF-TrkA signaling pathway.
Adaptor Proteins, Signal Transducing ; chemistry ; genetics ; metabolism ; Amino Acid Sequence ; Binding Sites ; Crystallography, X-Ray ; Gene Expression ; Humans ; Models, Molecular ; Molecular Sequence Data ; Nerve Growth Factor ; chemistry ; genetics ; metabolism ; Oncogene Protein p21(ras) ; chemistry ; genetics ; metabolism ; Protein Binding ; Protein Structure, Tertiary ; Receptor, trkA ; chemistry ; genetics ; metabolism ; Recombinant Proteins ; chemistry ; genetics ; metabolism ; Sequence Homology, Amino Acid ; Signal Transduction ; rab GTP-Binding Proteins ; chemistry

OBJECTIVETo investigate the inhibitory effect of somatostatin (SST) analogue octreotide on human gastric cancer.

METHODSFifty gastric cancer patients were randomly assigned into 2 equal groups. The patients in the control group received no medication before surgical resection of gastric cancer, and those in octreotide group were given daily subcutaneous injection of 100 µg octreotide for 7 days before the surgery. The resected specimens were examined histologically and the expressions of p53 and Ras protein were detected by immunohistochemistry.

RESULTSCompared with the control group, gastric cancer tissue in octreotide group showed significantly increased necrosis (P<0.05) and enhanced proliferation of fibrous tissues (P<0.05) with lowered expressions of p53 and Ras protein (P<0.05).

CONCLUSIONOctreotide can inhibit the expressions of p53 and Ras and suppress the growth of the human gastric cancer.

Adenocarcinoma ; drug therapy ; metabolism ; surgery ; Adult ; Aged ; Antineoplastic Agents ; therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Octreotide ; therapeutic use ; Proto-Oncogene Proteins p21(ras) ; genetics ; metabolism ; Somatostatin ; analogs & derivatives ; Stomach Neoplasms ; drug therapy ; metabolism ; surgery ; Tumor Suppressor Protein p53 ; genetics ; metabolism

This study is to investigate the antitumor activity of CIP-36 on multidrug resistant human oral squamous carcinoma cell line (KBV200 cells) in vitro and the possible anticancer mechanisms. MTT assay, Hoechst fluorescein stain, RT-PCR and immunohistochemistry were carried out on KBV200 and KB cells. The growth of many tumor cells was obviously inhibited by CIP-36, especially the multidrug resistant cells KBV200. Obvious apoptosis could be observed in the Hoechst 33342 staining experiments. The results of RT-PCR showed that the levels of p53, p21, caspase-3 and bax mRNA increased, and meanwhile the expression of mdr-1 and bcl-2 mRNA decreased in a dose-dependent manner. The data were significantly different from that of vehicle. The expression of P-gp significantly decreased with the increasing dosage of CIP-36 examined by immunohistochemistry. It can be concluded that CIP-36 could change resistance-related genes and proteins to overcome multidrug resistance in the KBV200 cell line.
ATP Binding Cassette Transporter, Sub-Family B ; ATP-Binding Cassette, Sub-Family B, Member 1 ; genetics ; metabolism ; Antineoplastic Agents, Phytogenic ; administration & dosage ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Caspase 3 ; genetics ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Humans ; KB Cells ; Mouth Neoplasms ; metabolism ; pathology ; Podophyllotoxin ; administration & dosage ; analogs & derivatives ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Proto-Oncogene Proteins p21(ras) ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Tumor Suppressor Protein p53 ; genetics ; metabolism ; bcl-2-Associated X Protein ; genetics ; metabolism

OBJECTIVETo investigate the effect of Abnormal Savda Munziq (ASMq) flavonoids on proliferation, apoptosis and apoptosis-related gene expression in human hepatoma (HepG2) cells in vitro and to probe the mechanism.

METHODThe effects of ASMq flavonoids on proliferation, apoptosis and apoptosis-related gene expression of HepG2 cells were investigated respectively by MTT assay, gel electrophoresis, flow cytometry and RT-PCR.

RESULTASMq flavonoids significantly inhibited growth of HepG2 cells in vitro, arrested HepG2 in the sub-G, phase, induced cell apoptosis and significantly down-regulated expression level of Bcl-2 mRNA, and up-regulated expression of p53, p21, Bax gene mRNA expressions.

CONCLUSIONASMq flavonoids has significantly regulative action on growth, apoptosis and apoptosis-related gene expression of cancer cells in vitro, which possibly are the important way to excert anticancer effect, and flavonoids are possibly a main active component of ASMq for exerting the anticancer effect.

Antineoplastic Agents, Phytogenic ; isolation & purification ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Drug Combinations ; Flavonoids ; isolation & purification ; pharmacology ; Flow Cytometry ; Humans ; Liver Neoplasms ; genetics ; metabolism ; pathology ; Plants, Medicinal ; chemistry ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; genetics ; Proto-Oncogene Proteins p21(ras) ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Suppressor Protein p53 ; biosynthesis ; genetics ; bcl-2-Associated X Protein ; biosynthesis ; genetics