Molecular alterations in AKT and its protein activation in human lung carcinomas

JAK1 Is a Novel Target of Tumor- and Invasion-Suppressive microRNA 494-5p in Colorectal Cancer

MiR-494-5p expression has been suggested to be associated with colorectal cancer (CRC) and its metastases in our previous studies. However, functional investigations on the molecule-mediating actions of this miR in CRC are lacking. In silico analysis in the present study revealed a putative binding sequence within the 3'UTR of JAK1. Overexpression of miR-494-5p in cultured CRC significantly reduced the luciferase activity of a reporter plasmid containing the wild-type JAK1-3'UTR, which was abolished by seed sequence mutation. Furthermore, the overexpression of miR-494-5p in CRC cell lines led to a significant reduction in JAK1 expression, proliferation, in vitro migration, and invasion. These effects were abolished by co-transfection with a specific double-stranded RNA that inhibits endogenous miR-494-5p. Moreover, IL-4-induced migration, invasion, and phosphorylation of JAK1, STAT6, and AKT proteins were reduced after an overexpression of this miR, suggesting that this miR affects one of the most essential pathways in CRC. A Kaplan-Meier plotter analysis revealed that patients with high JAK1 expression show reduced survival. Together, these data suggest that miR-494-5p physically inhibits the expression of JAK1 at the translational level as well as in migration and invasion, supporting the hypothesis of miR-494-5p as an early tumor suppressor and inhibitor of early steps of metastasis in CRC.

Interfering with the Ubiquitin-Mediated Regulation of Akt as a Strategy for Cancer Treatment

The serine/threonine kinase Akt modulates the functions of numerous substrates, many of them being involved in cell proliferation and growth, metabolism, angiogenesis, resistance to hypoxia and migration. Akt is frequently deregulated in many types of human cancers, its overexpression or abnormal activation being associated with the increased proliferation and survival of cancer cells. A promising avenue for turning off the functionality of Akt is to either interfere with the K63-linked ubiquitination that is necessary for Akt membrane recruitment and activation or increase the K48-linked polyubiquitination that aims to target Akt to the proteasome for its degradation. Recent evidence indicates that targeting the ubiquitin proteasome system is effective for certain cancer treatments. In this review, the functions and roles of Akt in human cancer will be discussed, with a main focus on molecules and compounds that target various elements of the ubiquitination processes that regulate the activation and inactivation of Akt. Moreover, their possible and attractive implications for cancer therapy will be discussed.

Targeting Akt in cancer for precision therapy

Biomarkers-guided precision therapeutics has revolutionized the clinical development and administration of molecular-targeted anticancer agents. Tailored precision cancer therapy exhibits better response rate compared to unselective treatment. Protein kinases have critical roles in cell signaling, metabolism, proliferation, survival and migration. Aberrant activation of protein kinases is critical for tumor growth and progression. Hence, protein kinases are key targets for molecular targeted cancer therapy. The serine/threonine kinase Akt is frequently activated in various types of cancer. Activation of Akt promotes tumor progression and drug resistance. Since the first Akt inhibitor was reported in 2000, many Akt inhibitors have been developed and evaluated in either early or late stage of clinical trials, which take advantage of liquid biopsy and genomic or molecular profiling to realize personalized cancer therapy. Two inhibitors, capivasertib and ipatasertib, are being tested in phase III clinical trials for cancer therapy. Here, we highlight recent progress of Akt signaling pathway, review the up-to-date data from clinical studies of Akt inhibitors and discuss the potential biomarkers that may help personalized treatment of cancer with Akt inhibitors. In addition, we also discuss how Akt may confer the vulnerability of cancer cells to some kinds of anticancer agents.

Expression of AKT and p-AKT protein in lung adenocarcinoma and its correlation with PD-L1 protein and prognosis

Background

The PI3K/AKT/mTOR signaling pathway were significantly associated with EGFR mutation in lung adenocarcinoma (LUAD), but its correlation with PD-L1 protein and prognosis are not clear. The aim of this study was to evaluate the expression of AKT and phosphorylated AKT (p-AKT) in LUAD and its correlation with programmed death ligand-1 (PD-L1); and to analyze the factors affecting LUAD prognosis.

Methods

The expression of AKT, p-AKT, and PD-L1 was examined using immunohistochemistry in LUAD tissues from 110 patients who underwent surgical treatment.

Results

AKT protein expression was examined in 64.5% (71/110) of the LUAD samples, and p-AKT protein expression was examined in 44.5% (49/110) of the LUAD samples. The positive rate of PD-L1 at TC1/2/3 was 38.2% (42/110). AKT and p-AKT expression was significantly associated with epidermal growth factor receptor (EGFR) mutation (P=0.016, P=0.014 respectively). Pearson's correlation analysis indicated a negative correlation of p-AKT with PD-L1 protein (P=0.022). Out of the 62 patients with EGFR mutation, the expression of PD-L1 was negatively correlated with that of p-AKT protein (P=0.032). The expressions of AKT and p-AKT were not associated with prognosis. Multivariate analysis showed that tumor-node-metastasis (TNM) stage (P=0.013) and differentiation (P=0.046) were independent prognostic factors for overall survival.

Conclusions

PI3K/AKT/mTOR in the downstream pathway of EGFR may negatively regulate the expression of PD-L1, which may partly explain why patients with EGFR mutation respond poorly to PD-1/PD-L1 inhibitors.

Targeting AKT/PKB to improve treatment outcomes for solid tumors

The serine/threonine kinase AKT, also known as protein kinase B (PKB), is the major substrate to phosphoinositide 3-kinase (PI3K) and consists of three paralogs: AKT1 (PKBα), AKT2 (PKBβ) and AKT3 (PKBγ). The PI3K/AKT pathway is normally activated by binding of ligands to membrane-bound receptor tyrosine kinases (RTKs) as well as downstream to G-protein coupled receptors and integrin-linked kinase. Through multiple downstream substrates, activated AKT controls a wide variety of cellular functions including cell proliferation, survival, metabolism, and angiogenesis in both normal and malignant cells. In human cancers, the PI3K/AKT pathway is most frequently hyperactivated due to mutations and/or overexpression of upstream components. Aberrant expression of RTKs, gain of function mutations in PIK3CA, RAS, PDPK1, and AKT itself, as well as loss of function mutation in AKT phosphatases are genetic lesions that confer hyperactivation of AKT. Activated AKT stimulates DNA repair, e.g. double strand break repair after radiotherapy. Likewise, AKT attenuates chemotherapy-induced apoptosis. These observations suggest that a crucial link exists between AKT and DNA damage. Thus, AKT could be a major predictive marker of conventional cancer therapy, molecularly targeted therapy, and immunotherapy for solid tumors. In this review, we summarize the current understanding by which activated AKT mediates resistance to cancer treatment modalities, i.e. radiotherapy, chemotherapy, and RTK targeted therapy. Next, the effect of AKT on response of tumor cells to RTK targeted strategies will be discussed. Finally, we will provide a brief summary on the clinical trials of AKT inhibitors in combination with radiochemotherapy, RTK targeted therapy, and immunotherapy.

Targeting DNA Double-Strand Break Repair Pathways to Improve Radiotherapy Response

More than half of cancer patients receive radiotherapy as a part of their cancer treatment. DNA double-strand breaks (DSBs) are considered as the most lethal form of DNA damage and a primary cause of cell death and are induced by ionizing radiation (IR) during radiotherapy. Many malignant cells carry multiple genetic and epigenetic aberrations that may interfere with essential DSB repair pathways. Additionally, exposure to IR induces the activation of a multicomponent signal transduction network known as DNA damage response (DDR). DDR initiates cell cycle checkpoints and induces DSB repair in the nucleus by non-homologous end joining (NHEJ) or homologous recombination (HR). The canonical DSB repair pathways function in both normal and tumor cells. Thus, normal-tissue toxicity may limit the targeting of the components of these two pathways as a therapeutic approach in combination with radiotherapy. The DSB repair pathways are also stimulated through cytoplasmic signaling pathways. These signaling cascades are often upregulated in tumor cells harboring mutations or the overexpression of certain cellular oncogenes, e.g., receptor tyrosine kinases, PIK3CA and RAS. Targeting such cytoplasmic signaling pathways seems to be a more specific approach to blocking DSB repair in tumor cells. In this review, a brief overview of cytoplasmic signaling pathways that have been reported to stimulate DSB repair is provided. The state of the art of targeting these pathways will be discussed. A greater understanding of the underlying signaling pathways involved in DSB repair may provide valuable insights that will help to design new strategies to improve treatment outcomes in combination with radiotherapy.

Clinical significance of Akt2 in advanced pancreatic cancer treated with erlotinib

Akt2 is an isoform of Akt, and an association between Akt2 and resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) has been suggested in pancreatic cancer (PC) in vitro. In this study, we investigated the association between Akt2 expression as evaluated using immunohistochemistry and the outcome of patients with advanced PC who had received treatment with erlotinib (an EGFR-TKI). Although the difference was not significant, patients with high levels of Akt2 expression tended to have a poorer response and a shorter progression-free survival period after treatment with erlotinib plus gemcitabine than those with low expression levels (P=0.16 and 0.19, respectively). In vitro, an Akt2-amplified PC cell line and Akt2-overexpressed cell lines exhibited resistance to anti-EGFR therapies, including erlotinib, but combined treatment with BYL719 (a PI3K inhibitor) cancelled this resistance. Our findings suggest that Akt2 might be associated with the resistance to anti-EGFR therapies, especially the use of erlotinib against PC, and that this resistance can be overcome by combined treatment with a PI3K inhibitor. Akt2 expression could become a predictive biomarker for erlotinib resistance in PC.

Unique roles of Akt1 and Akt2 in IGF-IR mediated lung tumorigenesis

AKT is a serine-threonine kinase that becomes hyperactivated in a number of cancers including lung cancer. Based on AKT's association with malignancy, molecules targeting AKT have entered clinical trials for solid tumors including lung cancer. However, the AKT inhibitors being evaluated in clinical trials indiscriminately inhibit all three AKT isoforms (AKT1-3) and it remains unclear whether AKT isoforms have overlapping or divergent functions. Using a transgenic mouse model where IGF-IR overexpression drives lung tumorigenesis, we found that loss of Akt1 inhibited while loss of Akt2 enhanced lung tumor development. Lung tumors that developed in the absence of Akt2 were less likely to appear as discrete nodules and more frequently displayed a dispersed growth pattern. RNA sequencing revealed a number of genes differentially expressed in lung tumors lacking Akt2 and five of these genes, Actc1, Bpifa1, Mmp2, Ntrk2, and Scgb3a2 have been implicated in human lung cancer. Using 2 human lung cancer cell lines, we observed that a selective AKT1 inhibitor, A-674563, was a more potent regulator of cell survival than the pan-AKT inhibitor, MK-2206. This study suggests that compounds selectively targeting AKT1 may prove more effective than compounds that inhibit all three AKT isoforms at least in the treatment of lung adenocarcinoma.

Association of chromosome 19 to lung cancer genotypes and phenotypes

The Chromosome 19 Consortium, a part of the Chromosome-Centric Human Proteome Project (C-HPP, http://www.C-HPP.org ), is tasked with the understanding chromosome 19 functions at the gene and protein levels, as well as their roles in lung oncogenesis. Comparative genomic hybridization (CGH) studies revealed chromosome aberration in lung cancer subtypes, including ADC, SCC, LCC, and SCLC. The most common abnormality is 19p loss and 19q gain. Sixty-four aberrant genes identified in previous genomic studies and their encoded protein functions were further validated in the neXtProt database ( http://www.nextprot.org/ ). Among those, the loss of tumor suppressor genes STK11, MUM1, KISS1R (19p13.3), and BRG1 (19p13.13) is associated with lung oncogenesis or remote metastasis. Gene aberrations include translocation t(15, 19) (q13, p13.1) fusion oncogene BRD4-NUT, DNA repair genes (ERCC1, ERCC2, XRCC1), TGFβ1 pathway activation genes (TGFB1, LTBP4), Dyrk1B, and potential oncogenesis protector genes such as NFkB pathway inhibition genes (NFKBIB, PPP1R13L) and EGLN2. In conclusion, neXtProt is an effective resource for the validation of gene aberrations identified in genomic studies. It promises to enhance our understanding of lung cancer oncogenesis.

Combination effects of arsenic trioxide and fibroblast growth factor receptor inhibitor in squamous cell lung carcinoma

OBJECTIVES

Lung cancer remains the top cancer killer worldwide, with squamous cell carcinoma (SCC) as the second commonest histologic subtype. Arsenic trioxide (ATO) was previously shown to suppress growth of lung cancer. Fibroblast growth factor receptor (FGFR) amplification was recently demonstrated in lung SCC, with specific FGFR inhibitor (e.g. PD173074) developed as a potential targeted therapy. Therefore the combination effects of ATO and PD173074 in SCC was studied.

MATERIALS AND METHODS

The combination of ATO/PD173074 was studied in a proof-of-principle model using a lung SCC cell line with FGFR1 overexpression: SK-MES-1. The effects of ATO and/or PD173074 on cell viability and protein expression were studied by MTT assay and Western blot respectively. Cell cycle analysis, phosphatidylserine externalization and mitochondrial membrane depolarization were monitored by flow cytometry. FGFR1 knockdown was performed with siRNAs. Proteasome inhibitor (MG-132) was used to study the degradation mechanism. In vivo effect of ATO and/or PD173074 was investigated using a nude mice xenograft model.

RESULTS

Combined ATO/PD173074 reduced cell viability along with increased sub-G1 population, phosphatidylserine externalization and mitochondrial membrane depolarization more significantly than single treatments. Downregulation of FGFR1, p-Akt, Akt, p-Src, Src, p-c-Raf, c-Raf, Erk and survivin as well as upregulation of p-Erk and cleaved PARP were observed upon ATO and/or PD treatment. MG-132 partially reversed the degradation of Akt, Src, c-Raf and Erk induced by ATO/PD, suggestive of ubiquitin-independent proteasome-dependent degradation. However, the mechanism of FGFR1 downregulation remained unknown. Downregulation of FGFR1, Akt, Src, c-Raf and Erk as well as cleaved PARP elevation induced by ATO and/or PD were confirmed in vivo.

CONCLUSION

Massive protein degradation (FGFR1, Akt, Src, c-Raf and Erk) was induced by ATO and/or PD173074 treatment mainly mediated by activation of proteasomal degradation in SCC cell line SK-MES-1 in vitro and in vivo.

Phosphatidylinositol 3-kinase/Akt signaling as a key mediator of tumor cell responsiveness to radiation

The phosphatidylinositol 3-kinase (PI3K)/Akt pathway is a key cascade downstream of several protein kinases, especially membrane-bound receptor tyrosine kinases, including epidermal growth factor receptor (EGFR) family members. Hyperactivation of the PI3K/Akt pathway is correlated with tumor development, progression, poor prognosis, and resistance to cancer therapies, such as radiotherapy, in human solid tumors. Akt/PKB (Protein Kinase B) members are the major kinases that act downstream of PI3K, and these are involved in a variety of cellular functions, including growth, proliferation, glucose metabolism, invasion, metastasis, angiogenesis, and survival. Accumulating evidence indicates that activated Akt is one of the major predictive markers for solid tumor responsiveness to chemo/radiotherapy. DNA double-strand breaks (DNA-DSB), are the prime cause of cell death induced by ionizing radiation. Preclinical in vitro and in vivo studies have shown that constitutive activation of Akt and stress-induced activation of the PI3K/Akt pathway accelerate the repair of DNA-DSB and, consequently, lead to therapy resistance. Analyzing dysregulations of Akt, such as point mutations, gene amplification or overexpression, which results in the constitutive activation of Akt, might be of special importance in the context of radiotherapy outcomes. Such studies, as well as studies of the mechanism(s) by which activated Akt1 regulates repair of DNA-DSB, might help to identify combinations using the appropriate molecular targeting strategies with conventional radiotherapy to overcome radioresistance in solid tumors. In this review, we discuss the dysregulation of the components of upstream regulators of Akt as well as specific modifications of Akt isoforms that enhance Akt activity. Likewise, the mechanisms by which Akt interferes with repair of DNA after exposure to ionizing radiation, will be reviewed. Finally, the current status of Akt targeting in combination with radiotherapy will be discussed.

Association between AKT1 Gene Polymorphism rs2498794 and Smoking-Related Traits with reference to Cancer Susceptibility

To clarify the potential role of variability within and around the AKT1 gene in smoking behaviors, we performed a single-nucleotide polymorphism (SNP) analysis of the AKT1 gene in an elderly Japanese cohort. Genotypes of the rs2498794 SNP, which is located in the fifth intron region of the AKT1 gene, were marginally but significantly associated with smoking duration in the total 999 samples of former and current smokers. Interestingly, this SNP had a marginally significant association with individual cancer history (past and current), especially in groups with a shorter smoking duration (<44 years) and fewer cigarettes per day (≤20). These data suggest that the rs2498794 polymorphism of the AKT1 gene is associated with a long smoking duration and may be involved in the predisposition to cancer when the smoking duration is short or the cigarettes per day is rate low.

Diverse involvement of isoforms and gene aberrations of Akt in human lung carcinomas

Emerging evidence confirms a central role of Akt in cancer. To evaluate the relative contribution of deregulated Akt and their clinicopathological significance in lung carcinomas, overexpression, activation of Akt and AKT gene increases were investigated. Immunohistochemical staining for 108 cases revealed overexpression of total Akt, Akt1, Akt2 and Akt3 in 61.1, 47.2, 40.7 and 23.1%, respectively, and phosphorylated Akt in 42.6% of cases. Expression of total Akt, Akt2 and Akt3 were frequently observed in small cell carcinoma, but phosphorylated Akt and Akt1 were more frequently observed in squamous cell carcinoma. FISH analysis to evaluate gene increases of AKT1-3 revealed amplification of AKT1 in 4.2% and AKT1 increase by polysomy of chromosome 14 in 27.3% of cases. For AKT2, amplification was observed in 3.2% and polysomy of chromosome 19 in 26.3% of cases. AKT3 increase was observed in 40.0% of cases only by polysomy of chromosome 1. Although “FISH-positive” AKT1 and AKT2 gene increases (amplification/high-level polysomy) were found exclusively in the cases overexpressing total Akt, Akt1 or Akt2, respectively, AKT3 increase was irrelevant of Akt3 expression. Statistically, expressions of Akt2, p-Akt and cytoplasmic-p-Akt were correlated with lymph node metastasis (P = 0.0479, P = 0.0371 and P = 0.0310, respectively). Although AKT1 and AKT2 gene increase showed positive correlation with, or trend towards a positive correlation with tumor size (P = 0.0430, P = 0.0590, respectively), AKT3 did not. In conclusion, Akt isoforms are differentially involved in the pathological phenotype of lung carcinoma in a diverse manner. Because abnormality of Akt1/AKT1 and Akt2/AKT2 correlated with clinicopathological profiles, Akt1/2-specific targeting may open a novel therapeutic window for the group showing Akt deregulation.

Combined comparative genomic hybridization and transcriptomic analyses of ovarian granulosa cell tumors point to novel candidate driver genes

Background

Ovarian granulosa cell tumors (GCTs) are the most frequent sex cord-stromal tumors. Several studies have shown that a somatic mutation leading to a C134W substitution in the transcription factor FOXL2 appears in more than 95% of adult-type GCTs. Its pervasive presence suggests that FOXL2 is the main cancer driver gene. However, other mutations and genomic changes might also contribute to tumor formation and/or progression.

Methods

We have performed a combined comparative genomic hybridization and transcriptomic analyses of 10 adult-type GCTs to obtain a picture of the genomic landscape of this cancer type and to identify new candidate co-driver genes.

Results

Our results, along with a review of previous molecular studies, show the existence of highly recurrent chromosomal imbalances (especially, trisomy 14 and monosomy 22) and preferential co-occurrences (i.e. trisomy 14/monosomy 22 and trisomy 7/monosomy 16q). In-depth analyses showed the presence of recurrently broken, amplified/duplicated or deleted genes. Many of these genes, such as AKT1, RUNX1 and LIMA1, are known to be involved in cancer and related processes. Further genomic explorations suggest that they are functionally related.

Conclusions

Our combined analysis identifies potential candidate genes, whose alterations might contribute to adult-type GCT formation/progression together with the recurrent FOXL2 somatic mutation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1283-0) contains supplementary material, which is available to authorized users.

Epidermal growth factor receptor and AKT1 gene copy numbers by multi-gene fluorescence in situ hybridization impact on prognosis in breast cancer

The epidermal growth factor receptor (EGFR)/PI3K/AKT signaling pathway aberrations play significant roles in breast cancer occurrence and development. However, the status of EGFR and AKT1 gene copy numbers remains unclear. In this study, we showed that the rates of EGFR and AKT1 gene copy number alterations were associated with the prognosis of breast cancer. Among 205 patients, high EGFR and AKT1 gene copy numbers were observed in 34.6% and 27.8% of cases by multi-gene fluorescence in situ hybridization, respectively. Co-heightened EGFR/AKT1 gene copy numbers were identified in 11.7% cases. No changes were found in 49.3% of patients. Although changes in EGFR and AKT1 gene copy numbers had no correlation with patients' age, tumor stage, histological grade and the expression status of other molecular makers, high EGFR (P = 0.0002) but not AKT1 (P = 0.1177) gene copy numbers correlated with poor 5-year overall survival. The patients with co-heightened EGFR/AKT1 gene copy numbers displayed a poorer prognosis than those with tumors with only high EGFR gene copy numbers (P = 0.0383). Both Univariate (U) and COX multivariate (C) analyses revealed that high EGFR and AKT1 gene copy numbers (P = 0.000 [U], P = 0.0001 [C]), similar to histological grade (P = 0.001 [U], P = 0.012 [C]) and lymph node metastasis (P = 0.046 [U], P = 0.158 [C]), were independent prognostic indicators of 5-year overall survival. These results indicate that high EGFR and AKT1 gene copy numbers were relatively frequent in breast cancer. Co-heightened EGFR/AKT1 gene copy numbers had a worse outcome than those with only high EGFR gene copy numbers, suggesting that evaluation of these two genes together may be useful for selecting patients for anti-EGFR-targeted therapy or anti-EGFR/AKT1-targeted therapy and for predicting outcomes.

Verifying the markers of ovarian cancer using RNA-seq data

Markers associated with diagnosis, presentation and potential therapeutic targets have received widespread attention in ovarian cancer research in the past few years. However, the majority of these markers have been investigated individually, and the changes in expression and the association between them are rarely documented. Next‑generation sequencing, also termed RNA-seq when the sequencing targets are cDNAs, can provide a whole blueprint of the transcriptome of a specific tissue. In the present study, RNA-seq data of human ovarian cancer samples were used to verify the expression of known markers and to identify the association between them. A total of 563 markers associated with ovarian cancer were retrieved from the database of the National Center of Biotechnology Information, and used as the target markers. The transcriptome of the ovarian tissue of four different tumors, containing tumor presentation and recurrence stages, were sequenced using the Illumina GAII platform. Approximately 85.97% markers were expressed of the total 563 markers, and the majority of them were involved in pathways associated with cancer, signaling and infection. In total, 85 markers were found to be aberrantly expressed in tumor cells from patients with ovarian cancer who had recurrences, including 33 upregulated markers at the recurrence stage. Therefore, they may have roles ovarian tumor due to their aberrant expression. Differentially expressed markers and the associations between them can be assessed by examining the RNA-seq data. These findings may provide novel information for further studies on ovarian cancer.

Significance of Akt activation and AKT gene increases in soft tissue tumors

To clarify the aberrations of AKT genes, their protein products and clinicopathologic significance in bone and soft tissue tumors, expression profiles of total Akt, its isoforms and activated Akt, and increases in copy number of AKT1/AKT2 genes were examined. Immunohistochemical analysis in 77 cases revealed overexpression of total Akt, Akt1, Akt2, and phosphorylated Akt in 84.4%, 67.5%, 72.7%, and 71.4%, respectively. Positive results were also observed in benign lesions but at a lower frequency. Overexpression of Akt1 was more frequent than that of Akt2 in well-differentiated liposarcoma (6/7 versus 3/7 cases) and schwannoma (4/4 versus 1/4 cases), whereas Akt2 overexpression and Akt activation were more frequent than Akt1 overexpression in malignant nerve sheath (3/4 and 4/4, respectively, versus 2/4 cases) and muscular tumors (8/9 and 8/9 versus 4/9 cases). By fluorescence in situ hybridization analysis, increase of gene copy number was observed in 13.3% for AKT1 and in 25.0% for AKT2 due to polysomy of chromosome 14 or 19, respectively, but not gene amplification. One case of schwannoma exhibited polysomy of both chromosomes 14 and 19. Akt activation was correlated with total Akt cytoplasmic localization (P = .0031) and subsequent metastasis (P = .0454). Moreover, AKT2 gene increase correlated with tumor size (P = .0352) and metastasis (P = .0344). In conclusion, in a defined subset of bone and soft tissue tumors, including benign tumors, Akt was frequently overexpressed and activated, and AKT1/2 copy number was increased. Because abnormality of Akt/AKT correlated with clinicopathologic profiles, novel therapies targeting isoform-specific Akts may be useful for these particular types of tumors.

Nestin regulates proliferation, migration, invasion and stemness of lung adenocarcinoma

Lung cancer is the most common cancer and the most common cause of cancer-related death in the world. Nestin, a class VI intermediate filament, is known to be a cancer stem cell (CSC) marker as well as a neuroepithelial stem cell marker. High expression levels of nestin are reported in several types of cancers including lung, pancreatic and prostate cancers. Nestin is thought to regulate tumor cell proliferation, migration, invasion and CSC properties. Here, we confirmed nestin expression in non-small cell lung cancer (NSCLC): Immunohistochemical analysis in surgical specimens detected nestin protein expression in the cytoplasm of 20 of 48 adenocarcinoma (AD) cases (41.7%) and 25 of 47 squamous cell carcinoma cases (53.2%). Nestin immunoreactivity significantly correlated with not only tumor size and lymph node metastasis in NSCLC, but also poor survival in surgical patients with AD. High and moderate expression levels of nestin were confirmed in several lung AD cell lines including H1975 and PC-3. Nestin inhibition by shRNA decreased proliferation, migration, invasion and sphere formation in AD cells. Correspondingly, nestin upregulation by nestin gene transfection resulted in the opposite changes. Moreover, Akt inhibitor IV effectively decreased nestin expression via SRY-box containing protein 2 (Sox2) downregulation and overcame the enhanced sphere formation induced by nestin upregulation. Overall, our results show that nestin correlates with the aggressiveness and stemness of AD. Regulation of nestin via Akt/Sox2 is, thus, a promising candidate for novel therapeutic approaches to eradicate CSCs in lung AD.

New targets in non-small cell lung cancer

Lung cancer remains the most common cause of cancer-related death in the United States. At presentation, the majority of patients have regional or systemic metastases and therefore require systemic therapy. For years, chemotherapy was the only systemic therapy option. A major paradigm shift has occurred in recent years with the identification of driver genetic alterations in some non-small cell lung cancers (NSCLCs). It is part of current standard of care to assess epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) translocations in tumors of patients with advanced NSCLC. Drugs targeting these mutations provide significant clinical benefit and are the preferred therapeutic option in these patients. Ongoing clinical trials are assessing the clinical benefit from targeting other driver genetic alterations. Further therapeutic targets have been identified through greater understanding of the variety of molecular processes that facilitate tumor formation and progression. Some of these new therapeutic targets are heat shock proteins and targets that can allow enhanced anti-tumor immune response. It is expected that these advances will allow personalized management of NSCLC patients and move us away from approaching all NSCLC patients with the same therapeutic tools.