Multiple genetic alterations within the PI3K pathway are responsible for AKT activation in patients with ovarian carcinoma

Role of Akt/Protein Kinase B in Cancer Metastasis

Metastasis is a critical step in the process of carcinogenesis and a vast majority of cancer-related mortalities result from metastatic disease that is resistant to current therapies. Cell migration and invasion are the first steps of the metastasis process, which mainly occurs by two important biological mechanisms, i.e., cytoskeletal remodelling and epithelial to mesenchymal transition (EMT). Akt (also known as protein kinase B) is a central signalling molecule of the PI3K-Akt signalling pathway. Aberrant activation of this pathway has been identified in a wide range of cancers. Several studies have revealed that Akt actively engages with the migratory process in motile cells, including metastatic cancer cells. The downstream signalling mechanism of Akt in cell migration depends upon the tumour type, sites, and intracellular localisation of activated Akt. In this review, we focus on the role of Akt in the regulation of two events that control cell migration and invasion in various cancers including head and neck squamous cell carcinoma (HNSCC) and the status of PI3K-Akt pathway inhibitors in clinical trials in metastatic cancers.

The Potential of PI3K/AKT/mTOR Signaling as a Druggable Target for Endometrial and Ovarian Carcinomas

AIMS

In this narrative review, we summarize the role and significance of PI3K-AKTmTOR (PAM) pathway in ovarian and endometrial cancers, providing the most recent and relevant literature on the topic and addressing options for targeting PAM along with future perspectives of drug development.

BACKGROUND

Alterations of the PAM-pathway are common in both endometrial and ovarian cancers, and are described in specific histology-defined subtypes. PAM seems to be involved in critical steps of endometrial and ovarian carcinogenesis, often mechanistically involved in the acquisition of a phenotype of treatment resistance, which could be targetable. However, early clinical trials with PAMinhibitors (PAMi) have provided disappointing results, particularly when non isoform-specific inhibitors were tested in unselected populations, accompanied by an adverse safety profile. Since then, more encouraging observations have been collected when targeting specific isoforms of PAM proteins with more selective drugs, resulting in encouraging activity and more manageable toxicity.

CONCLUSION

Although the rationale of inhibiting the PAM-pathway has been demonstrated in several promising preclinical studies, no Phase III clinical trial is available to demonstrate a significant benefit of PAM-inhibitors. A way to manage targeted agents is to tailor their use to particular subpopulations most likely to obtain a considerable benefit, namely pursuing an individualized, precision-medicine approach.

Association of Inflammation-Related Gene Polymorphisms With Susceptibility and Radiotherapy Sensitivity in Head and Neck Squamous Cell Carcinoma Patients in Northeast China

Background

Inflammation-related gene polymorphisms are some of the most important determinants for cancer susceptibility, clinical phenotype diversity, and the response to radiotherapy and chemotherapy. However, the relationship between these polymorphisms and head and neck squamous cell carcinoma (HNSCC) remains unclear. The aim of this study was to investigate the role of inflammation-related gene polymorphisms in the developmental risk and radiotherapy sensitivity of HNSCC.

Methods

The Matrix-Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) genotyping system was used to genotype 612 individuals from a Chinese population for 28 inflammation-related gene polymorphisms.

Results

The protein kinase B (AKT1) rs1130233 TT, dominance model (CT+TT vs. CC), recessive model (TT vs. CT+CC), and rs2494732 CC genotypes were associated with reduced risk of HNSCC (P=0.014; P=0.041; P=0.043). The polymeric immunoglobulin receptor (PIGR) rs291097 GA, dominance model (GA+AA vs. GG), and rs291102 dominance model (GA+AA vs. GG) were associated with increased risk of HNSCC (P=0.025; P=0.025; P=0.040). The interleukin-4 receptor-α (IL-4RA) rs1801275 AA genotype was significantly correlated with increased radiotherapy sensitivity of HNSCC patients (P=0.030). In addition, age ≤ 60 years, non-smoker status, and normal levels of squamous cell carcinoma antigen (SCC) were found to be associated with increased radiotherapy sensitivity of HNSCC patients (P=0.033; P=0.033; P=0.030).

Conclusion

The AKT1 rs1130233, AKT1 rs2494732, PIGR rs291097, and PIGR rs291102 polymorphisms were significantly related to the risk of HNSCC. The IL-4RA rs1801275 polymorphism, age ≤ 60 years, non-smoker status, and normal levels of SCC were significantly associated with increased radiotherapy sensitivity of HNSCC.

An Immunohistochemical Study of the PTEN/AKT Pathway Involvement in Canine and Feline Mammary Tumors

Simple Summary

The PTEN/AKT pathway is involved in several human and animal tumors’ pathogenesis. This study investigates the PTEN/AKT pathway’s biological and prognostic values in canine and feline mammary tumors. PTEN, phospho-AKT (p-AKT) and Rictor expression was determined by immunohistochemistry in canine mammary adenomas and carcinomas and feline mammary carcinomas. In mammary tumors of both species p-Akt was inversely correlated with PTEN expression and positively with Rictor expression; p-Akt and Rictor expression correlated with poorer prognosis. This data could provide a rationale for further studies of this pathway in veterinary oncology due to prognostic and therapeutic implications.

Abstract

Phosphatase and tensin homolog deleted on chromosome10 (PTEN), phospho-v-Akt murine thymoma viral oncogene homolog (AKT), and the Rapamycin-Insensitive Companion of mTOR (Rictor) expression was investigated by immunohistochemistry in 10 canine mammary adenomas (CMAs), 40 canine mammary carcinomas (CMCs), and 30 feline mammary carcinomas (FMCs). All the CMAs, 25 of 40 CMCs (63%) and 7 of 30 FMCs (23%), were PTEN-positive. In dogs, no CMAs and 15 of 25 CMCs (37%) expressed phospho-AKT (p-AKT), while 24 of 30 FMCs (82%) were p-AKT-positive. One of 10 CMAs (10%), 24 of 40 CMCs (60%) and 20 of 30 FMCs (67%) were Rictor-positive. In the dog, PTEN expression correlated with less aggressive tumors, absence of lymphatic invasion, and longer survival. P-AKT expression correlated with more aggressive subtype, lymphatic invasion, and poorer survival and Rictor expression with lymphatic invasion. In cats, PTEN correlated with less aggressive carcinomas, absence of lymphatic invasion, and better survival. P-AKT and Rictor expression correlated with poorer survival. PTEN expression was inversely correlated with p-AKT and Rictor in both species, while p-AKT positively correlated with Rictor expression. A strong PTEN/AKT pathway involvement in behavior worsening of CMT and FMTs is demonstrated, providing a rationale for further studies of this pathway in veterinary oncology.

Screening for PIK3CA mutations among Saudi women with ovarian cancer

The study aimed to screen for PIK3CA gene mutations among Saudi women with Ovarian Cancer. The study included 298 Saudi women with epithelial ovarian cancers (EOC). DNA sequence analysis was employed to screen for the mutations. DNA sequence analysis of a coding region of exon 9 and 20 of PIK3CA gene revealed mutations in 37/298 (12.4%) EOC patients. About 21/37(56.8%) somatic mutations were identified in exons 9, and 16/37(43.2%) in exon 20. All analysed mutations were missense mutations, the frequencies of which varied from 2.7% to 43.2%. PIK3CA mutation was found to be significantly associated with age (p = .023), grade (p = .001) and histological types (p = .032). Only 6.6% of serous carcinomas and 3.8% of endometrioid had PIK3CA mutation. The Mutated PIK3CA gene was significantly involved in the pathogenesis of EOC among Saudi women. PIK3CA gene mutation and overexpression represent important clinical implications for diagnosis, and prognosis, which can be utilised for better EOC management.Impact statementWhat is already known on this subject? The detailed molecular and genetic phenomenon underlying the progression of these tumours is still unclear. Recently, the pathogenesis of ovarian cancer has been attributed to mutations of PIK3CA.What do the results of this study add? Mutation in the PIK3CA gene leads to altered PI3K/AKT signalling pathways responsible for the progression of the epithelial ovarian cancer.What are the implications of these findings for clinical practice and/or further research? The Mutated PIK3CA gene was significantly involved in the pathogenesis of EOC among Saudi women. PIK3CA gene mutation and overexpression represent important clinical implications for diagnosis, and prognosis, which can be utilised for better EOC management.

AKT1 Polymorphism (rs10138227) and Risk of Colorectal Cancer in Moroccan Population: A Case Control Study

BACKGROUND

LMTK3 and AKT1 each have a role in carcinogenesis and tumor progression. The analysis of single nucleotide polymorphisms of AKT1 and LMTK3 could lead to more complete and accurate risk estimates for colorectal cancer.

AIM

We evaluated the association between single nucleotide polymorphisms (SNPs) of AKT1 and LMTK3 and the risk of colorectal cancer in a case-control study in Moroccan population.

METHODS

Genomic DNA from 70 colorectal cancer patients and 50 healthy control subjects was extracted from whole blood. Genotyping was performed by direct sequencing after polymerase chain reactions for the 7 SNPs (AKT1rs1130214G/T, AKT1rs10138227C/T, AKT1rs3730358C/T, AKT1rs1000559097G/A, AKT1rs2494737A/T, LMTK3rs8108419G/A, and LMTK3rs9989661A/G.). Study subjects provided detailed information during the collection. All P values come from bilateral tests.

RESULTS

In the logistic regression analysis, a significantly high risk of colorectal cancer was associated with TC/TT genotypes of rs10138227 with adjusted odds ratio [OR] equal to 2.82 and 95% confidence interval [CI] of 1.15 to 6.91.

CONCLUSION

Our results suggest that the SNP AKT1rs10138227 could affect susceptibility to CRC, probably by modulating the transcriptional activity of AKT1. However, larger independent studies are needed to validate our results.

PI3K/AKT pathway as a key link modulates the multidrug resistance of cancers

Multidrug resistance (MDR) is the dominant challenge in the failure of chemotherapy in cancers. Phosphatidylinositol 3-kinase (PI3K) is a lipid kinase that spreads intracellular signal cascades and regulates a variety of cellular processes. PI3Ks are considered significant causes of chemoresistance in cancer therapy. Protein kinase B (AKT) is also a significant downstream effecter of PI3K signaling, and it modulates several pathways, including inhibition of apoptosis, stimulation of cell growth, and modulation of cellular metabolism. This review highlights the aberrant activation of PI3K/AKT as a key link that modulates MDR. We summarize the regulation of numerous major targets correlated with the PI3K/AKT pathway, which is further related to MDR, including the expression of apoptosis-related protein, ABC transport and glycogen synthase kinase-3 beta (GSK-3β), synergism with nuclear factor kappa beta (NF-κB) and mammalian target of rapamycin (mTOR), and the regulation of glycolysis.

Detection of PIK3R1 (L449S) Mutation in a Patient with Ovarian Cancer: A Case Report

Ovarian cancer (OC) is one of the most dangerous gynecological diseases and greatly increases the death risk worldwide. The heterogeneity of the ovarian tumors among patients and the lack of sufficient therapies for these tumors make the selection of the appropriate treatment a hard challenge. Understanding the mechanisms leading to OC becomes an urgent need in order to find out better therapeutic strategies. In this study, we have identified a point mutation (L449S) in the regulatory subunit of PI3K in an OC Lebanese patient. This genomic alteration had not been previously reported in OC and could plausibly enhance the PIK3CA amplification effect in strengthening AKT/mTOR pathway activity and leading to tumorigenesis.

Results of an abbreviated phase II study of AKT inhibitor MK-2206 in the treatment of recurrent platinum-resistant high grade serous ovarian, fallopian tube, or primary peritoneal carcinoma (NCT 01283035)

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PI3K/AKT pathway alterations are frequently seen in ovarian cancer, providing rationale for targeted AKT inhibition.

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AKT inhibitor MK-2206 in platinum resistant high grade serous ovarian cancer was notable for dermatologic toxicity.

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Best response of stable disease was seen, with one patient experiencing a prolonged SD of 19 weeks.

Platinum-resistant, recurrent, high grade epithelial ovarian carcinoma remains challenging to treat. Chemotherapy produces limited responses with modest survival benefits in the treatment of recurrent disease. In this context, targeted therapies may improve upon conventional therapies. PI3K/AKT pathway alterations are frequently found in several cancer types, including ovarian cancer, and thus AKT inhibition is a rational targeted therapy. Here we report the results of an abbreviated trial of AKT inhibitor MK-2206 in platinum resistant high grade serous ovarian, fallopian tube, and primary peritoneal cancer with PTEN loss.

Differential expression of mTOR components in endometriosis and ovarian cancer: Effects of rapalogues and dual kinase inhibitors on mTORC1 and mTORC2 stoichiometry

Endometriosis is a well‑known risk factor for ovarian cancer. The genetic changes that characterise endometriosis are poorly understood; however, the mechanistic target of rapamycin (mTOR) pathway is involved. In this study, we investigated the expression of key mTOR components in endometriosis and the effects of rapalogues using an endometrioid ovarian carcinoma cell line (MDAH 2774) as an in vitro model. Gene expression of mTOR, DEPTOR, Rictor and Raptor was assessed by qPCR in 24 endometriosis patients and in silico in ovarian cancer patients. Furthermore, the effects of Rapamycin, Everolimus, Deforolimus, Temsirolimus, Resveratrol, and BEZ235 (Dactolisib, a dual kinase inhibitor) on mTOR signalling components was assessed. mTOR showed a significant increase in the expression in endometriosis and ovarian endometrioid adenocarcinoma patients compared to non‑affected controls. DEPTOR, an inhibitor of mTOR, was downregulated in the advanced stages of ovarian cancer (III and IV) compared to earlier stages (I and II). Treatment of MDAH‑2774 cells with the mTOR inhibitors resulted in the significant upregulation of DEPTOR mRNA, whereas treatment with rapamycin and BEZ‑235 (100 nM) resulted in downregulation of the mTOR protein expression after 48 h of treatment. None of the treatments resulted in translocation of mTOR from cytoplasm to nucleus. Upregulation of DEPTOR is a positive prognostic marker in ovarian cancer and is increased in response to mTOR pathway inhibition suggesting that it functions as a tumour suppressor gene in endometrioid ovarian carcinoma. Collectively, our data suggest the mTOR pathway as a potential connection between endometriosis and ovarian cancer and may be a potential target in the treatment of both conditions.

Serum- and glucocorticoid-inducible kinase 3 is a potential oncogene in nasopharyngeal carcinoma

INTRODUCTION

Serum- and glucocorticoid-inducible kinase 3, a serine/threonine kinase that functions downstream of the PI3K signaling pathway, plays a critical role in neoplastic processes. It is expressed by various tumors and contributes to carcinogenesis.

OBJECTIVE

The objective was to investigate serum- and glucocorticoid-inducible kinase 3 expression in nasopharyngeal carcinoma, to study the anti-tumor effects of serum- and glucocorticoid-inducible kinase 3 shRNA by inhibiting its expression in nasopharyngeal carcinoma cells and to discuss the potential implications of our findings.

METHODS

Serum- and glucocorticoid-inducible kinase 3 protein expression in nasopharyngeal carcinoma cell lines (CNE-1, CNE-2, HNE-1, HONE-1, and SUNE-1) and the human immortalized nasopharyngeal epithelium cell line NP69 were assayed by western blotting. Serum- and glucocorticoid-inducible kinase 3 expression in 42 paraffin-embedded nasopharyngeal carcinoma tissues were performed by immunohistochemistry. MTT assay, flow cytometry, and scratch tests were performed after CNE-2 cells were transfected with the best serum- and glucocorticoid-inducible kinase 3 shRNA plasmid selected by western blotting using lipofectamine to study its effect on cell proliferation, apoptosis, and migration.

RESULTS

Serum- and glucocorticoid-inducible kinase 3 was overexpressed in human nasopharyngeal carcinoma tissues and cells. Serum- and glucocorticoid-inducible kinase 3 expression decreased markedly after CNE-2 cells were transfected with the serum- and glucocorticoid-inducible kinase 3 shRNA, leading to strong inhibition of cell proliferation and migration. In addition, the apoptosis rate increased in CNE-2 cells after serum- and glucocorticoid-inducible kinase 3 knockdown.

CONCLUSION

Serum- and glucocorticoid-inducible kinase 3 expression was more frequently observed as the nasopharyngeal epithelium progresses from normal tissue to carcinoma. This suggests that serum- and glucocorticoid-inducible kinase 3 contributes to the multistep process of NPC carcinogenesis. Serum- and glucocorticoid-inducible kinase 3 represents a target for nasopharyngeal carcinoma therapy, and a basis exists for the further investigation of this adjuvant treatment modality for nasopharyngeal carcinoma.

HMGA1 Overexpression is Associated With the Malignant Status and Progression of Breast Cancer

Breast cancer is the most common malignant tumor among women, and the incidence and mortality of breast cancer has rapidly increased in recent years. Studies have indicated that high mobility group A1 (HMGA1), an important member of the HMGA family, plays a role in the pathogenesis and progression of malignant tumors, including breast cancer. This study aims to evaluate the effect of HMGA1 in breast cancer. Interestingly, we found that HMGA1 expression was significantly higher in breast cancer tissues than in adenoma tissues and closely correlated with the clinical stage and histological grade in breast cancer patients. Further study showed that HMGA1 knockdown inhibited the proliferation and migration of breast cancer cells. Thus, the results demonstrated that HMGA1 could act as an independent prognostic indicator in breast cancer. HMGA1 expression was closely correlated with the clinical stage, histological grade, and tumor size in breast cancer patients and breast cancer progression in transgenic MMTV-PyMT mice. Anat Rec, 301:1061-1067, 2018. © 2018 Wiley Periodicals, Inc.

Akt activation by Ca2+/calmodulin-dependent protein kinase kinase 2 (CaMKK2) in ovarian cancer cells

Hyperactivation of Akt is associated with oncogenic changes in the growth, survival, and chemoresistance of cancer cells. The PI3K/phosphoinositide-dependent kinase (PDK) 1 pathway represents the canonical mechanism for phosphorylation of Akt at its primary activation site, Thr-308. We observed that Ca²⁺/calmodulin (CaM)-dependent protein kinase kinase 2 (β) (CaMKK2) is highly expressed in high-grade serous ovarian cancer, and we investigated its role in Akt activation in ovarian cancer (OVCa) cell lines (OVCAR-3, SKOV-3, and Caov-3). Knockdown or pharmacological inhibition of CaMKK2 produced phenotypes expected of Akt inhibition, including reductions in cell growth and cell viability and in the regulation of Akt downstream targets involved in G₁/S transition and apoptosis. CaMKK2 knockdown or inhibition decreased Akt phosphorylation at Thr-308 and Ser-473 to extents similar to those of PDK1 knockdown or PI3K inhibition. Combined CaMKK2 and PDK1 knockdown or CaMKK and PI3K inhibition, respectively, produced additive effects on p-Akt and cell growth, consistent with direct Akt phosphorylation by CaMKK2. This conclusion was supported by the absence of effects of CaMKK2 knockdown/inhibition on alternative means of activating Akt via p-Akt Thr-450, p-PDK1 Ser-241, or p-IRS1 Ser-636/639. Recombinant CaMKK2 directly activated recombinant Akt by phosphorylation at Thr-308 in a Ca²⁺/CaM-dependent manner. In OVCa cells, p-Akt Thr-308 was significantly inhibited by intracellular Ca²⁺_i chelation or CaM inhibition. Ionomycin-induced Ca²⁺ influx promoted p-Akt, an effect blocked by PDK1, and/or CaMKK2, siRNAs, and by PI3K and/or CaMKK inhibitors. CaMKK2 knockdown potentiated the effects of the chemotherapeutic drugs carboplatin and PX-866 to reduce proliferation and survival of OVCa cells.

The Akt1/IL-6/STAT3 pathway regulates growth of lung tumor initiating cells

Here we report that the PI3K/Akt1/IL-6/STAT3 signalling pathway regulates generation and stem cell-like properties of Non-Small Cell Lung Cancer (NSCLC) tumor initiating cells (TICs). Mutant Akt1, mutant PIK3CA or PTEN loss enhances formation of lung cancer spheroids (LCS), self-renewal, expression of stemness markers and tumorigenic potential of human immortalized bronchial cells (BEAS-2B) whereas Akt inhibition suppresses these activities in established (NCI-H460) and primary NSCLC cells. Matched microarray analysis of Akt1-interfered cells and LCSs identified IL-6 as a critical target of Akt signalling in NSCLC TICs. Accordingly, suppression of Akt in NSCLC cells decreases IL-6 levels, phosphorylation of IkK and IkB, NF-kB transcriptional activity, phosphorylation and transcriptional activity of STAT3 whereas active Akt1 up-regulates them. Exposure of LCSs isolated from NSCLC cells to blocking anti-IL-6 mAbs, shRNA to IL-6 receptor or to STAT3 markedly reduces the capability to generate LCSs, to self-renew and to form tumors, whereas administration of IL-6 to Akt-interfered cells restores the capability to generate LCSs. Finally, immunohistochemical studies in NSCLC patients demonstrated a positive correlative trend between activated Akt, IL-6 expression and STAT3 phosphorylation (n = 94; p < 0.05). In conclusion, our data indicate that aberrant Akt signalling contributes to maintaining stemness in lung cancer TICs through a NF-kB/IL-6/STAT3 pathway and provide novel potential therapeutic targets for eliminating these malignant cells in NSCLC.

Use of comprehensive genomic profiling to direct point-of-care management of patients with gynecologic cancers

OBJECTIVE

To determine the feasibility and clinical utility of using comprehensive genomic profiling (CGP) in the course of clinical care to identify clinically relevant tumor genomic alterations for patients with either rare or refractory gynecologic cancers to facilitate point-of-care management. Use of an expert, multidisciplinary, institutional molecular tumor board (MTB) assessment is discussed regarding input on putative targeted options for individualized therapy.

METHODS

A prospective clinical trial is ongoing. We report on the initial 69 patients with gynecologic cancers that were either rare or refractory to standard therapy. CGP was performed by Foundation Medicine, Inc. Genomic alterations were reviewed by members of an MTB. Consensus recommendations on genomically targeted, FDA-approved, on- and off-label therapies and clinical trials were sent to the treating physician, and decisions and outcomes were assessed.

RESULTS

Study outcomes were available for 64 patients. The mean number of genes altered per tumor was 4.97 (median=4; range, 1-26), and the average turnaround time from testing laboratory report to generation of formal recommendations was approximately three weeks. Evaluation of genomic and clinical data by the MTB led to generation of targeted treatment options in all 64 patients, and the percentage of patients for whom one or more of these recommendations were implemented by the treating physician was 39%. Sixty-four percent of the patients receiving targeted therapy based on a CGP result experienced radiologic response or showed evidence of clinical benefit or stable disease.

CONCLUSION

These data suggest that an institutional MTB is a feasible venue for reviewing tumor genomic profiling results and generating clinical recommendations. These data also support the need for further studies and guidelines on clinical decision making with greater availability of broad genomically based diagnostics.

RY-2f, an isoflavone analog, overcomes cisplatin resistance to inhibit ovarian tumorigenesis via targeting the PI3K/AKT/mTOR signaling pathway

Ovarian cancer remains the leading cause of death in gynecologic malignancies partially because of resistance to chemotherapy. In the present study, we show that RY-2f, a chemically synthesized isoflavone analog, inhibited ovarian cancer cell proliferation, blocked cell cycle in G2/M phase and induced cellular apoptosis through up-regulation of p21, cyclin B1, Bax, Bad and cleaved-PARP, and suppression of cyclin A, CDK2 and Bcl-2. We also show that RY-2f could increase the chemotherapeutic efficacy of cisplatin as tested by cell proliferation and colony formation assays, indicating a synergistic effect of RY-2f and cisplatin. Mechanistic study revealed that RY-2f exerted the anti-tumor activities mainly through suppression of the PI3K/AKT/mTOR signaling. Finally, in vivo studies showed that RY-2f blocked the A2780-induced xenograft tumor growth without detectable toxicity in the animals at the therapeutic doses, and whereas RY-2f re-sensitized the cisplatin resistant cell line A2780/CDDP induced xenograft tumor to cisplatin treatment. Thus, RY-2f may be developed as a potential therapeutic agent to treat ovarian cancer.

Exome sequencing of lymphomas from three dog breeds reveals somatic mutation patterns reflecting genetic background

Lymphoma is the most common hematological malignancy in developed countries. Outcome is strongly determined by molecular subtype, reflecting a need for new and improved treatment options. Dogs spontaneously develop lymphoma, and the predisposition of certain breeds indicates genetic risk factors. Using the dog breed structure, we selected three lymphoma predisposed breeds developing primarily T-cell (boxer), primarily B-cell (cocker spaniel), and with equal distribution of B- and T-cell lymphoma (golden retriever), respectively. We investigated the somatic mutations in B- and T-cell lymphomas from these breeds by exome sequencing of tumor and normal pairs. Strong similarities were evident between B-cell lymphomas from golden retrievers and cocker spaniels, with recurrent mutations in TRAF3-MAP3K14 (28% of all cases), FBXW7 (25%), and POT1 (17%). The FBXW7 mutations recurrently occur in a specific codon; the corresponding codon is recurrently mutated in human cancer. In contrast, T-cell lymphomas from the predisposed breeds, boxers and golden retrievers, show little overlap in their mutation pattern, sharing only one of their 15 most recurrently mutated genes. Boxers, which develop aggressive T-cell lymphomas, are typically mutated in the PTEN-mTOR pathway. T-cell lymphomas in golden retrievers are often less aggressive, and their tumors typically showed mutations in genes involved in cellular metabolism. We identify genes with known involvement in human lymphoma and leukemia, genes implicated in other human cancers, as well as novel genes that could allow new therapeutic options.

Risk prediction model for epithelial ovarian cancer using molecular markers and clinical characteristics

BACKGROUND

A high-quality risk prediction model is urgently needed for the clinical management of ovarian cancer. However most existing models are solely based on clinical parameters, and molecular classifications in recent reports are still being debated. This study aimed to establish a risk prediction model by using both clinicopathological and molecular factors (the synthetic model) for epithelial ovarian cancer.

METHODS

A retrospective cohort study was conducted in epithelial ovarian cancer patients (n = 161) treated with primary debulking surgery and adjuvant chemotherapy. The expression level of 15 selected molecular markers were measured using immunohistochemistry. A risk model was developed using COX regression analysis with overall survival as the primary outcome. A simplified scoring system for each prognostic factor was based on its coefficient. Independent validation (n = 40) was conducted to evaluate the performance of the model.

RESULTS

A total of 10 out of 15 molecular markers were significantly associated with clinical characteristics and overall survival. The synthetic model performed better than the clinicopathological risk model or the molecular risk model alone, as assessed by analysis of the receiver-operating characteristics curve area and the Youden index. The synthetic model included parity (>3), peritoneal metastasis, stage, tumor type, residual disease, and expression of human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), breast cancer 1 (BRCA1), murine sarcoma viral oncogene homolog B (BRAF) and Kirsten rat sarcoma viral oncogene homolog (KRAS).

CONCLUSIONS

Our synthetic risk model may more accurately predict survival of epithelial ovarian cancer patients than current models.

Expression of EGFR, PIK3CA and PIK3CB in colorectal carcinoma

AIM: To investigate the expression of epidermal growth factor receptor (EGFR), PIK3CA and PIK3CB in colorectal cancer (CRC), to analyze the correlation between EGFR, PIK3CA and PIK3CB expression, and to discuss their role in the occurrence, development and targeted therapy of CRC.

METHODS: Immunohistochemistry was employed to detect the expression of EGFR, PIK3CA and PIK3CB in 120 CRC and 30 normal mucosa tissue sample (from the margin of the lesion > 5 cm), and the correlation between EGFR, PIK3CA and PIK3CB expression as well their relationship with clinicopathological factors were analyzed.

RESULTS: The positive expression rates of EGFR, PIK3CA and PIK3CB in CRC were 48%, 55.7% and 75.9%, respectively, which were significantly higher than those in tumor adjacent tissues (P < 0.05). In EGFR positive CRC tissues, 68.9% were PIK3CA positive and 72.4% was PIK3CB positive, while in EGFR negative CRC tissues, 43.5% were PIK3CA positive and 21.0% were PIK3CB positive. EGFR receptor expression was significantly different from the expression of PIK3CA and PIK3CB (P < 0.05). The expression of EGFR, PIK3CA and PIK3CB was positively correlated with tumor differentiation and lymph node metastasis in CRC (P < 0.05). Kaplan-Meier analysis revealed that the 5-year survival rate was significantly correlated with lymph node metastasis, EGFR, PIK3CA and PIK3CB expression. Multivariate analysis revealed that lymph node metastasis, EGFR, PIK3CA and PIK3CB expression could serve as independent predictive factors for overall survival.

CONCLUSION: EGFR, PIK3CA and PIK3CB are highly expressed in CRC, and their expression is closely correlated with tumor differentiation and lymph node metastasis. The high expression of PIK3CA and PIK3CB is not only correlated with the activation of EGFR, but also correlated with mutation by itself. The mutation of PIK3CA and PIK3CB genes in colorectal cancer may be a factor to influence therapies targeting EGFR in CRC.

Association of MTOR and AKT Gene Polymorphisms with Susceptibility and Survival of Gastric Cancer

Background

The phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB, AKT)/mammalian target of rapamycin (mTOR) signaling pathway plays a critical role in angiogenesis and cell growth, proliferation, metabolism, migration, differentiation, and apoptosis. Genetic diversity in key factors of this pathway may influence protein function and signal transduction, contributing to disease initiation and progression. Studies suggest that MTOR rs1064261 and AKT rs1130233 polymorphisms are associated with risk and/or prognosis of multiple cancer types. However, this relationship with gastric cancer (GC) remains unclear. The aim of this study was to investigate the role of MTOR and AKT polymorphisms in the risk and prognosis of GC.

Methods

The Sequenom MassARRAY platform was used to genotype 1842 individuals for MTOR rs1064261 T→C and AKT rs1130233 G→A polymorphisms. ELISA was used to detect Helicobacter pylori antibodies in serum. Immunohistochemical analysis was used to detect total and phosphorylated MTOR and AKT proteins.

Results

The MTOR rs1064261 (TC+CC) genotype and the AKT rs1130233 (GA+AA) genotype were associated with increased risk of GC in men (P = 0.049, P = 0.030). In H. pylori-negative individuals, the AKT rs1130233 GA and (GA+AA) genotypes were related to increased risk of atrophic gastritis (AG; P = 0.012, P = 0.024). Notably, the AKT rs1130233 (GA+AA) genotype demonstrated significant interactions with H. pylori in disease progression from healthy controls (CON) to AG (P = 0.013) and from AG to GC (P = 0.049). Additionally, for individuals with the AKT rs1130233 variant, those in the H. pylori-positive group had higher levels of phosphorylated AKT (p-AKT) expression. The AKT rs1130233 genotype was found to be associated with clinicopathological parameters including lymph node metastasis and alcohol drinking (P<0.05).

Conclusion

MTOR rs1064261and AKT rs1130233 polymorphisms were associated with increased GC risk in males and increased AG risk in H. pylori-negative individuals. A significant interaction existed between the AKT rs1130233 genotype and H. pylori infection in CON→AG→GC disease progression. The AKT rs1130233 genotype influenced p-AKT protein expression in H. pylori-infected individuals.

ARID2, p110α, p53, and β-catenin protein expression in hepatocellular carcinoma and clinicopathologic implications

ARID2 (ARID2), CTNNB1 (β catenin), tumor protein 53 (p53), and PIK3CA (p110α) mutations are implicated in hepatocellular carcinoma (HCC); and previous work has contributed to thorough molecular characterization of these events. However, studies that assess the impact of these mutations on downstream protein expression, especially those that evaluate all 4 cancer markers simultaneously, are relatively lacking. Hence, the present study uses immunohistochemistry to assess protein expression patterns of ARID2, β-catenin, p53, and p110α in HCCs and adjacent nonneoplastic cirrhotic tissues from 58 explanted livers. Notably, this study is the first to our knowledge to investigate ARID2 protein expression in the liver. The frequency of ARID2 mutations detected using our immunohistochemistry method was similar to that reported in previous molecular studies. Furthermore, we found that loss of ARID2 protein expression may be associated with recurrence, although further studies must be done to validate these findings in a larger population. We found that expression patterns of the 4 cancer markers were independent of each other, suggesting separate pathways of hepatocarcinogenesis. We also did not observe an association between viral etiology and protein expression. Consistent with previous studies, overexpression of p53 correlated with poor differentiation. Lastly, 17.5% of HCCs paradoxically had diffuse loss of the oncoprotein p110α compared with strong expression in background cirrhotic liver. The exact mechanism is unclear, but enigmatic loss of oncoprotein function has been described in other carcinomas and could potentially have significant implications for the use of mechanistic target of rapamycin (mTOR) drug therapies.

Oligonucleotide PIK3CA/Chromosome 3 Dual in Situ Hybridization Automated Assay with Improved Signals, One-Hour Hybridization, and No Use of Blocking DNA

The PIK3CA gene at chromosome 3q26.32 was found to be amplified in up to 45% of patients with squamous cell carcinoma of the lung. The strong correlation between PIK3CA amplification and increased phosphatidylinositol 3-kinase (PI3K) pathway activities suggested that PIK3CA gene copy number is a potential predictive biomarker for PI3K inhibitors. Currently, all microscopic assessments of PIK3CA and chromosome 3 (CHR3) copy numbers use fluorescence in situ hybridization. PIK3CA probes are derived from bacterial artificial chromosomes whereas CHR3 probes are derived mainly from the plasmid pHS05. These manual fluorescence in situ hybridization assays mandate 12- to 18-hour hybridization and use of blocking DNA from human sources. Moreover, fluorescence in situ hybridization studies provide limited morphologic assessment and suffer from signal decay. We developed an oligonucleotide-based bright-field in situ hybridization assay that overcomes these shortcomings. This assay requires only a 1-hour hybridization with no need for blocking DNA followed by indirect chromogenic detection. Oligonucleotide probes produced discrete and uniform CHR3 stains superior to those from the pHS05 plasmid. This assay achieved successful staining in 100% of the 195 lung squamous cell carcinoma resections and in 94% of the 33 fine-needle aspirates. This robust automated bright-field dual in situ hybridization assay for the simultaneous detection of PIK3CA and CHR3 centromere provides a potential clinical diagnostic method to assess PIK3CA gene abnormality in lung tumors.

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.

Loss of serum and glucocorticoid-regulated kinase 3 (SGK3) does not affect proliferation and survival of multiple myeloma cell lines

Multiple myeloma (MM) is a generally fatal plasma cell cancer that often shows activation of the phosphoinositide 3-kinase/Akt (PI3K/Akt) pathway. Targeted pharmacologic therapies, however, have not yet progressed beyond the clinical trial stage, and given the complexity of the PI3K/Akt signalling system (e.g. multiple protein isoforms, diverse feedback regulation mechanisms, strong variability between patients) it is mandatory to characterise its ramifications in order to better guide informed decisions about the best therapeutic approaches. Here we explore whether serum and glucocorticoid-regulated kinase 3 (SGK3), a potential downstream effector of PI3K, plays a role in oncogenic signalling in MM cells—either in concert with or independent of Akt. SGK3 was expressed in all MM cell lines and in all primary MM samples tested. Four MM cell lines representing a broad range of intrinsic Akt activation (very strong: MM.1s, moderate: L 363 and JJN-3, absent: AMO-1) were chosen to test the effects of transient SGK3 knockdown alone and in combination with pharmacological inhibition of Akt, PI3K-p110α, or in the context of serum starvation. Although the electroporation protocol led to strong SGK3 depletion for at least 5 days its absence had no substantial effect on the activation status of potential downstream substrates, or on the survival, viability or proliferation of MM cells in all experimental contexts tested. We conclude that it is unlikely that SGK3 plays a significant role for oncogenic signalling in multiple myeloma.

Tubulin-binding agents down-regulate matrix metalloproteinase-2 and -9 in human hormone-refractory prostate cancer cells – a critical role of Cdk1 in mitotic entry

Tubulin is an important target for anticancer therapy. Taxanes and vinca alkaloids are two groups of tubulin-binding agents in cancer chemotherapy. Besides tubulin binding, these groups of agents can also down-regulate protein levels of matrix metalloproteinase (MMP)-2 and -9, two important cancer-associated zinc-dependent endopeptidases in invasion and metastasis. However, the mechanism of action waits to be explored. In this study, protein levels but not mRNA expressions of MMP-2 and -9 were down-regulated by paclitaxel (a microtubule-stabilization agent), vincristine and evodiamine (two tubulin-depolymerization agents). These agents induced an increase of protein expression of cyclin B1, MPM2 (mitosis-specific phosphoprotein) and polo-like kinase (PLK) 1 phosphorylation. The data showed a negative relationship between the levels of mitotic proteins and MMP-2 and -9 expressions. MG132 (a specific cell-permeable proteasome inhibitor) blocked mitotic entry and arrested cell cycle at G2 phase, preventing down-regulation of MMP-2 and -9. Cell cycle synchronization experiments by thymidine block or nocodazole treatment showed that mitotic exit inhibited the down-regulation of MMP-2 and -9, confirming negative relationship between cell mitosis and protein levels of MMP-2 and -9 expressions. Cyclin-dependent kinase (Cdk) 1 is a key kinase in mitotic entry. Knockdown of Cdk1 almost completely inhibited the down-regulation of MMP-2 and -9 induced by tubulin-binding agents. In conclusion, the data suggest that mitotic entry and Cdk1 plays a central role in down-regulation of MMP-2 and -9 protein expressions. Tubulin-binding agents cause mitotic arrest and Cdk1 activation, which may contribute largely to the down-regulation of both MMP-2 and -9 expressions.

AT-rich interactive domain 2, p110α, p53, and β-catenin protein expression in hepatocellular carcinoma and clinicopathologic implications

AT-rich interactive domain 2 (ARID2), catenin (cadherin-associated protein), beta 1, 88kDa (β-catenin), tumor protein 53 (p53), and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (p110α) mutations are implicated in hepatocellular carcinoma (HCC); and previous work has contributed to thorough molecular characterization of these events. However, studies that assess the impact of these mutations on downstream protein expression, especially those that evaluate all 4 cancer markers simultaneously, are relatively lacking. Hence, the present study uses immunohistochemistry to assess protein expression patterns of ARID2, β-catenin, p53, and p110α in HCCs and adjacent nonneoplastic cirrhotic tissues from 58 explanted livers. Notably, this study is the first to our knowledge to investigate ARID2 protein expression in the liver. The frequency of ARID2 mutations detected using our immunohistochemistry method was similar to that reported in previous molecular studies. Furthermore, we found that loss of ARID2 protein expression may be associated with recurrence, although further studies must be done to validate these findings in a larger population. We found that expression patterns of the 4 cancer markers were independent of each other, suggesting separate pathways of hepatocarcinogenesis. We also did not observe an association between viral etiology and protein expression. Consistent with previous studies, overexpression of p53 correlated with poor differentiation. Lastly, 17.5% of HCCs paradoxically had diffuse loss of the oncoprotein p110α compared with strong expression in background cirrhotic liver. The exact mechanism is unclear, but enigmatic loss of oncoprotein function has been described in other carcinomas and could potentially have significant implications for the use of targeted mechanistic target of rapamycin (serine/threonine kinase) drug therapies.

N-myc downstream regulated gene 1 acts as a tumor suppressor in ovarian cancer

Although implicated in a number of tumor types, the role of N-myc downstream regulated gene 1 (NDRG1) in ovarian cancer (OC) is unclear. In the present study, we used short hairpin RNA (shRNA) to silence NDRG1 in the OC cell line OVCAR3 and assessed the effect of its knockdown on cell morphology, proliferation, colony formation, migration and invasion. To complement these knockdown studies, we overexpressed NDRG1 in the same cell line. We found that NDRG1 knockdown significantly enhanced OVCAR3 proliferation, migration and invasion; however, there were no apparent changes in cell morphology. We also examined the effect in vivo and found that NDRG1 depletion promoted OVCAR3 xenograft growth in nude mice. In accordance with these data, we found that NDRG1 overexpression decreased proliferation, adhesion and apoptosis, and induced G0/G1 cell cycle arrest in OVCAR3 cells; expression of p21 and p53 was also increased. In conclusion, we demonstrated that NDRG1 acts as a tumor suppressor in ovarian carcinogenesis and may be a potential therapeutic target in this disease.

AKT-independent PI3-K signaling in cancer - emerging role for SGK3

The phosphoinositide 3-kinase (PI3-K) signaling pathway plays an important role in a wide variety of fundamental cellular processes, largely mediated via protein kinase B/v-akt murine thymoma viral oncogene homolog (PKB/AKT) signaling. Given the crucial role of PI3-K/AKT signaling in regulating processes such as cell growth, proliferation, and survival, it is not surprising that components of this pathway are frequently dysregulated in cancer, making the AKT kinase family members important therapeutic targets. The large number of clinical trials currently evaluating PI3-K pathway inhibitors as a therapeutic strategy further emphasizes this. The serum- and glucocorticoid-inducible protein kinase (SGK) family is made up of three isoforms, SGK1, 2, and 3, that are PI3-K-dependent, serine/threonine kinases, with similar substrate specificity to AKT. Consequently, the SGK family also regulates similar cell processes to the AKT kinases, including cell proliferation and survival. Importantly, there is emerging evidence demonstrating that SGK3 plays a critical role in AKT-independent oncogenic signaling. This review will focus on the role of SGK3 as a key effector of AKT-independent PI3-K oncogenic signaling.