The role of estrogen, progesterone and aromatase in human non-small-cell lung cancer

Autocrine 17-β-Estradiol/Estrogen Receptor-α Loop Determines the Response to Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer

PURPOSE

The response to immune checkpoint inhibitors (ICI) often differs between genders in non-small cell lung cancer (NSCLC), but metanalyses results are controversial, and no clear mechanisms are defined. We aim at clarifying the molecular circuitries explaining the differential gender-related response to anti-PD-1/anti-PD-L1 agents in NSCLC.

EXPERIMENTAL DESIGN

We prospectively analyzed a cohort of patients with NSCLC treated with ICI as a first-line approach, and we identified the molecular mechanisms determining the differential efficacy of ICI in 29 NSCLC cell lines of both genders, recapitulating patients' phenotype. We validated new immunotherapy strategies in mice bearing NSCLC patient-derived xenografts and human reconstituted immune system ("immune-PDXs").

RESULTS

In patients, we found that estrogen receptor α (ERα) was a predictive factor of response to pembrolizumab, stronger than gender and PD-L1 levels, and was directly correlated with PD-L1 expression, particularly in female patients. ERα transcriptionally upregulated CD274/PD-L1 gene, more in females than in males. This axis was activated by 17-β-estradiol, autocrinely produced by intratumor aromatase, and by the EGFR-downstream effectors Akt and ERK1/2 that activated ERα. The efficacy of pembrolizumab in immune-PDXs was significantly improved by the aromatase inhibitor letrozole, which reduced PD-L1 and increased the percentage of antitumor CD8+T-lymphocytes, NK cells, and Vγ9Vδ2 T-lymphocytes, producing durable control and even tumor regression after continuous administration, with maximal benefit in 17-β-estradiol/ERα highfemale immune-xenografts.

CONCLUSIONS

Our work unveils that 17-β-estradiol/ERα status predicts the response to pembrolizumab in patients with NSCLC. Second, we propose aromatase inhibitors as new gender-tailored immune-adjuvants in NSCLC. See related commentary by Valencia et al., p. 3832.

Novel Host Pathways Govern Epithelial Cell Invasion of Aspergillus fumigatus

Invasive aspergillosis is initiated when Aspergillus fumigatus adheres to and invades the pulmonary epithelial cells that line the airways and alveoli. To gain deeper insight into how pulmonary epithelial cells respond to A. fumigatus invasion, we used transcriptome sequencing (RNA-seq) to determine the transcriptional response of the A549 type II alveolar epithelial cell line to infection with strains CEA10 and Af293, two clinical isolates of A. fumigatus. Upstream regulator analysis of the data indicated that while both strains activated virtually identical host cell signaling pathways after 16 h of infection, only strain CEA10 activated these pathways after 6 h of infection. Many of the pathways that were predicted to be activated by A. fumigatus, including the tumor necrosis factor (TNF), interleukin-1α (IL-1α), IL-1β, IL-17A, Toll-like receptor 2 (TLR2), and TLR4 pathways, are known to be critical for the host defense against this fungus. We also found that the platelet-derived growth factor BB (PDGF BB) and progesterone receptor (PGR) pathways were activated by A. fumigatus. Using pharmacologic inhibitors, we determined that blocking the PDGF receptor or PGR inhibited the endocytosis of both strains of A. fumigatus in an additive manner. Both the PDGF BB and PGR pathways are also predicted to be activated by infection of A549 cells with other molds, such as Rhizopus delemar and Rhizopus oryzae. Thus, these pathways may represent a common response of pulmonary epithelial cells to mold infection. IMPORTANCE Invasive aspergillosis is a deadly invasive fungal infection that initiates when Aspergillus fumigatus spores are inhaled and come into contact with the epithelial cells that line the airways and alveoli. Understanding this fungus-host interaction is important for the development of novel therapeutics. To gain a deeper understanding of how these airway epithelial cells respond to A. fumigatus during infection, we used RNA-seq to determine the transcriptional response of alveolar epithelial cells to infection with two different clinical isolates of A. fumigatus. Our analysis identified new host response pathways that have not previously been tied to infection with A. fumigatus. Pharmacological inhibition of two of these pathways inhibited the ability of A. fumigatus to invade airway epithelial cells. These two pathways are also predicted to be activated by infection with other filamentous fungi. Thus, these pathways may represent a common response of alveolar epithelial cells to mold infection.

Sex-specificity in Surgical Stages of Lung Cancer in Young Adults

Background

Young Patients with lung cancer represent a distinct subset of patients with this neoplasm. Young International studies show increased lung cancer rates in females, while the incidence in males continues to decline. There is evidence to suggest that this trend recurs in younger patients. We studied the effects of gender differences on the incidence of surgical stages of lung cancer in young adults and its mortality rate.

Methods

This study is a retrospective review (2010-2020) of young adults (aged under 45 years) with surgical-stage of lung cancer. We calculated female-to-male differences in incidence rate ratios, tumor characteristics, surgical management, and survival. Cumulative survival curves were generated by the Kaplan-Meier method.

Results

We examined 46 men and 24 women, under 45 years. Female patients were diagnosed at earlier stages. The proportion of stage IA disease was significantly higher in women than in men (46% versus 13%, respectively) (p=0.03). Women were more likely never smokers (42% versus 83%, p=0.02). A histologic subtype, females were more likely to have typical carcinoid tumors (13.54% versus 10.21% for males) (p>0.05). The largest histological type in men was adenocarcinoma (25.53% versus 4.16%, p>0.05). All the patients were operated. Three men had neoadjuvant chemotherapy and one was operated on for cerebral oligometastatic before his chest surgery. Adjuvant chemotherapy was given to 7 women and 21 men. Despite the small number of postoperative complications in our study (n= 8, 11.2%), the male sex was significant in predicting this complication (p<0.05). The mortality rate was 1.4%. The 5-year overall survival rates were 84% in men and 87% in women.

Conclusion

Our study identified sex differences in the incidence and mortality rates for surgical lung cancers in young adults, but the biological and endocrine mechanisms implicated in these disparities have not yet been determined.

Sex Differences in Lung Cancer

Sex disparities in the incidence and mortality of lung cancer have been observed since cancer statistics have been recorded. Social and economic differences contribute to sex disparities in lung cancer incidence and mortality, but evidence suggests that there are also underlying biological differences that contribute to the disparity. This review summarizes biological differences which could contribute to the sex disparity. Sex hormones and other biologically active molecules, tumor cell genetic differences, and differences in the immune system and its response to lung cancer are highlighted. How some of these differences contribute to disparities in the response to therapies, including cytotoxic, targeted, and immuno-therapies, is also discussed. We end the study with a discussion of our perceived future directions to identify the key biological differences which could contribute to sex disparities in lung cancer and how these differences could be therapeutically leveraged to personalize lung cancer treatment to the individual sexes.

The Tri-iodothyronine (T3) Level Is a Prognostic Factor for Patients With Advanced NSCLC: Receiving Immune Checkpoint Inhibitors and Is Associated With Liver Metastasis

BACKGROUND

Endocrine hormones influence tumor progression and the response to treatment. Despite the importance of immune checkpoint inhibitors (ICIs) as treatments for advanced non-small cell lung cancer (NSCLC), few studies have explored the effects of hormone levels in NSCLC patients on the effectiveness of ICI therapies. We thus investigated the effects of baseline blood markers in patients with advanced NSCLC on ICI treatments.

METHODS

Patients with advanced NSCLC who received programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors at Chungnam National University Hospital between December 2016 and November 2020 and who lacked any history of thyroid gland-related diseases were analyzed retrospectively. We collected clinical information and baseline laboratory data, including the levels of endocrine hormones, cytokines, complete blood counts (CBCs), and peripheral blood chemistry panels. We explored the relationships of hormone levels with clinical outcomes (overall survival [OS], progression-free survival [PFS], and best response), liver metastasis, and blood markers using the Kaplan-Meier method, Cox's proportional hazards regression, and logistic regression.

RESULTS

A total of 113 patients were enrolled. A shorter PFS was independently associated with liver metastasis, higher cortisol levels, and lower hemoglobin (Hb) levels; a shorter OS was associated with liver metastasis, lower tri-iodothyronine (T3) levels, higher lactate dehydrogenase (LDH) levels, and lower albumin levels. Patients with low T3 levels exhibited a shorter PFS and OS, and a poorer best response. Patients with low T3 levels tended to have higher disease progression rates, lower levels of adrenocorticotropic hormone (ACTH), C-peptide, albumin, Hb, and neutrophil-to-lymphocyte ratio, and higher levels of interleukin (IL)-6, white blood cells, platelets, compared with those with normal T3 levels. We found a significant association between a low T3 level and liver metastasis.

CONCLUSIONS

We found the baseline T3 level was associated with both prognosis and the response to ICIs in patients with advanced NSCLC, probably reflecting impaired liver function and systemic inflammation induced by the interaction of T3 with other biomarkers, such as IL-6, ACTH, cortisol, C-peptide, Hb, LDH, and albumin.

Estrogen induces the expression of EBV lytic protein ZEBRA, a marker of poor prognosis in nasopharyngeal carcinoma

Several epidemiological studies have suggested that Epstein-Barr virus (EBV) lytic infection is essential for the development of nasopharyngeal carcinoma (NPC), as elevation of antibody titers against EBV lytic proteins is a common feature of NPC. Although ZEBRA protein is a key trigger for the initiation of lytic infection, whether its expression affects the prognosis and pathogenesis of NPC remains unclear. In this study, 64 NPC biopsy specimens were analyzed using immunohistochemistry. We found that ZEBRA was significantly associated with a worsening of progression-free survival in NPC (adjusted hazard ratio, 3.58; 95% confidence interval, 1.08-11.87; P = 0.037). Moreover, ZEBRA expression positively correlated with key endocrinological proteins, estrogen receptor α, and aromatase. The transcriptional level of ZEBRA is activated by estrogen in an estrogen receptor α-dependent manner, resulting in an increase in structural gene expression levels and extracellular virus DNA copy number in NPC cell lines, reminiscent of lytic infection. Interestingly, it did not suppress cellular proliferation or increase apoptosis, in contrast to cells treated with 12-O-tetradecanoylphorbol-13-acetate and sodium butyrate, indicating that viral production induced by estrogen is not a cell lytic phenomenon. Our results suggest that intratumoral estrogen overproduced by aromatase could induce ZEBRA expression and EBV reactivation, contributing to the progression of NPC.

Investigation of Combination Treatment With an Aromatase Inhibitor Exemestane and Carboplatin-Based Therapy for Postmenopausal Women With Advanced NSCLC

Introduction

Estrogen receptors (ER) (ERα, ERβ) and aromatase (key enzyme for estrogen synthesis) are expressed in most human NSCLCs. High intratumoral estrogen levels and elevated aromatase expression in NSCLC predict poor outcome. This open-label, phase 1b, single-center study evaluated the safety and tolerability of escalating doses of the aromatase inhibitor, exemestane, in combination with carboplatin and pemetrexed in postmenopausal women with stage IV nonsquamous NSCLC.

Methods

Patients received exemestane (starting 1-wk before chemotherapy) at 25 mg orally (PO) daily (cohort 1) or 50 mg PO daily (cohort 2) combined with carboplatin (area under the curve 6 mg × min/mL) and pemetrexed (500 mg/m²) intravenously every 3 weeks for four cycles. Thereafter, patients were eligible for continued therapy with exemestane and pemetrexed or pemetrexed alone.

Results

A total of 10 patients consented for therapy, and two patients failed in the screening. Four patients completed the therapy in cohort 1 and four patients in cohort 2. The median number of cycles administered was 15 (range: 1-54). Maximum tolerated dose was exemestane 50 mg PO daily with combination chemotherapy. Intention-to-treat analysis revealed an objective response rate (ORR) of 62.5% (five of eight patients with partial response) and a clinical benefit rate of 87.5% (seven of eight patients with either stable disease or partial response). ORR was associated with aromatase expression (p = 0.02). Circulating estrogen levels decreased with exemestane use, and quality of life measurements did not significantly change during the treatment. There were no adverse events.

Conclusions

The combination of carboplatin, pemetrexed, and exemestane in postmenopausal women with metastatic NSCLC is safe and well tolerated. Biomarker studies revealed that ORR correlates with tumor aromatase expression. These findings support future clinical trials to confirm the antitumor efficacy with this combination therapy.

Role of sex hormones in lung cancer

Lung cancer represents the world's leading cause of cancer deaths. Sex differences in the incidence and mortality rates for various types of lung cancers have been identified, but the biological and endocrine mechanisms implicated in these disparities have not yet been determined. While some cancers such as lung adenocarcinoma are more commonly found among women than men, others like squamous cell carcinoma display the opposite pattern or show no sex differences. Associations of tobacco product use rates, susceptibility to carcinogens, occupational exposures, and indoor and outdoor air pollution have also been linked to differential rates of lung cancer occurrence and mortality between sexes. While roles for sex hormones in other types of cancers affecting women or men have been identified and described, little is known about the influence of sex hormones in lung cancer. One potential mechanism identified to date is the synergism between estrogen and some tobacco compounds, and oncogene mutations, in inducing the expression of metabolic enzymes, leading to enhanced formation of reactive oxygen species and DNA adducts, and subsequent lung carcinogenesis. In this review, we present the literature available regarding sex differences in cancer rates, associations of male and female sex hormones with lung cancer, the influence of exogenous hormone therapy in women, and potential mechanisms mediated by male and female sex hormone receptors in lung carcinogenesis. The influence of biological sex on lung disease has recently been established, thus new research incorporating this variable will shed light on the mechanisms behind the observed disparities in lung cancer rates, and potentially lead to the development of new therapeutics to treat this devastating disease.

The smoking estrogens - a potential synergy between estradiol and benzo(a)pyrene

According to recent statistics, Lung Cancer (LC) is one of the most frequently diagnosed tumor types, representing nearly 12% of all global cancer cases. Moreover, in recent years, an increased mortality rate and incidence of this cancer were observed, especially among nonsmokers. Lung cancer patients are often characterized by poor prognosis and low survival rates, which encourages the scientific community to investigate the biochemical and molecular processes leading to the development of this malignancy. Furthermore, the mechanisms of LC formation and progression are not yet fully elucidated due to their high complexity, as well as a multitude of environmental, genetic, and molecular factors involved. Even though LC's association with exposure to cigarette smoke is indisputable, current research provides evidence that the development of this cancer can also be affected by the presence of estrogens and their interaction with several tobacco smoke components. Hence, the main goal of this brief review was to investigate reports of a possible synergy between 17β estradiol (E2), the most biologically active estrogen, and benzo(a)pyrene (BaP), a strongly carcinogenic compound produced as a result of incomplete tobacco combustion. The literature sources demonstrate a possible carcinogenic synergy between estrogens, especially E2, and BaP, a toxic tobacco smoke component. Therefeore, the combined effect of disturbed estrogen production in cancer cells, as well as the molecular influence exerted by BaP, could explain the increased aggressiveness and rate of LC development. Summarizing, the synergistic effect of these risk factors is an interesting area of further research.

In Vitro Transformation of Human Bronchial Epithelial Cells by Diesel Exhaust Particles: Gene Expression Profiling and Early Toxic Responses

Occupational exposure to diesel exhaust may cause lung cancer in humans. Mechanisms include DNA-damage and inflammatory responses. Here, the potential of NIST SRM2975 diesel exhaust particles (DEP) to transform human bronchial epithelial cells (HBEC3) in vitro was investigated. Long-term exposure of HBEC3 to DEP led to increased colony growth in soft agar. Several DEP-transformed cell lines were established and based on the expression of epithelial-to-mesenchymal-transition (EMT) marker genes, one of them (T2-HBEC3) was further characterized. T2-HBEC3 showed a mesenchymal/fibroblast-like morphology, reduced expression of CDH1, and induction of CDH2 and VIM. T2-HBEC3 had reduced migration potential compared with HBEC3 and little invasion capacity. Gene expression profiling showed baseline differences between HBEC3 and T2-HBEC3 linked to lung carcinogenesis. Next, to assess differences in sensitivity to DEP between parental HBEC3 and T2-HBEC3, gene expression profiling was carried out after DEP short-term exposure. Results revealed changes in genes involved in metabolism of xenobiotics and lipids, as well as inflammation. HBEC3 displayed a higher steady state of IL1B gene expression and release of IL-1β compared with T2-HBEC3. HBEC3 and T2-HBEC3 showed similar susceptibility towards DEP-induced genotoxic effects. Liquid-chromatography-tandem-mass-spectrometry was used to measure secretion of eicosanoids. Generally, major prostaglandin species were released in higher concentrations from T2-HBEC3 than from HBEC3 and several analytes were altered after DEP-exposure. In conclusion, long-term exposure to DEP-transformed human bronchial epithelial cells in vitro. Differences between HBEC3 and T2-HBEC3 regarding baseline levels and DEP-induced changes of particularly CYP1A1, IL-1β, PGE2, and PGF2α may have implications for acute inflammation and carcinogenesis.

Impact of estrogen monotherapy on survival in women with stage III-IV non-small cell lung cancer

OBJECTIVES

Women with lung cancer have better survival than men. The reasons are unknown, but estrogen is hypothesized to improve survival. Our objective was to examine the association between estrogen monotherapy and cancer-specific and overall survival in elderly women with non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

We used the SEER-Medicare database to identify women ≥65 years old who were diagnosed with stage III or IV NSCLC. Estrogen monotherapy (EM) was defined as at least one estrogen claim without any progesterone claims 6 months prior to diagnosis. To assess cancer-specific survival and overall survival, we used Kaplan-Meier and multivariate Cox modeling with propensity score adjustments. As an exploratory analysis, we also examined the effect of combined estrogen and progesterone hormonal therapy on survival using Cox modeling.

RESULTS

We identified 6958 women in our initial cohort: 283 used EM (4%) and 6675 (96%) did not. The median follow-up time was 46.5 months in the EM patients and 49.5 months in the non-EM patients. In a Kaplan-Meier analysis, median overall survival was 8.2 months in patients who receive EM and 6.2 months in those who did not (p = 0.004). In our 1:4 propensity-matched cohort, median follow-up was 46.5 in the EM group and 50.6 in the non-EM group; median overall survival was 8.0 months in the EM group and 6.4 months in the non-EM group (p = 0.02). In a multivariate Cox regression of the matched cohort, EM was significantly associated with overall survival (HR 0.84; 95% CI 0.73 - 0.97). All results were similar for cancer-specific survival. In our exploratory analysis, combined Estrogen-Progesterone did significantly impact overall survival (HR 0.84; 95% CI 0.71-0.99, p = 0.04) but did not appear to effect cancer-specific survival (HR 0.91; 95% CI 0.77-1.09, p = 0.30).

CONCLUSION

EM was associated with a significant improvement in cancer-specific survival and overall survival in women with late stage NSCLC.

Potential Mechanisms of Age Acceleration Caused by Estrogen Deprivation: Do Endocrine Therapies Carry the Same Risks?

Longer duration of endocrine therapy decreases breast cancer recurrence and mortality, but these benefits need to be weighed against potential risks to overall health. Notable side effects of endocrine therapy include cataracts, uterine cancer, thromboembolic events, osteoporosis and fracture risk, chronic musculoskeletal complaints, as well as vaginal dryness and discharge, and vasomotor symptoms. Estrogen deprivation in healthy women younger than 50 years undergoing bilateral oophorectomy has been shown to accelerate the development of diseases related to aging, including coronary artery disease, cardiac arrhythmias, stroke, dementia, and osteoporosis, raising concern that even less dramatic modulation of estrogen homeostasis may adversely affect health outcomes. Diminished available estrogen at the cellular and molecular level may facilitate mechanisms that underlie the aging process, often termed the hallmarks of aging. In this review, we describe estrogen's role in normal physiology across tissues, review the effects of estrogen deprivation on health outcomes in the setting of both surgical and natural menopause, and examine the hallmarks of aging with attention to the effects of estrogen and estrogen blockade on each molecular mechanism underlying the aging process.

Randomized phase II study of fulvestrant and erlotinib compared with erlotinib alone in patients with advanced or metastatic non-small cell lung cancer

OBJECTIVES

This open-label, randomized phase II trial evaluated antitumor efficacy of an antiestrogen, fulvestrant, in combination with human epidermal growth factor receptor (EGFR) inhibitor, erlotinib, in advanced non-small cell lung cancer (NSCLC) patients.

MATERIALS AND METHODS

Patients with advanced or metastatic NSCLC, ECOG 0-2, previous chemotherapy unless patient refusal, and no prior EGFR-directed therapy were randomized 2:1 to erlotinib 150 mg oral daily plus 500 mg intramuscular fulvestrant on day 1, 15, 29 and every 28 days thereafter or erlotinib alone 150 mg oral daily. The primary end point was objective response rate (ORR); secondary endpoints included progression free survival (PFS) and overall survival (OS).

RESULTS

Among 106 randomized patients, 100 received at least one dose of study drug. ORR was 16.4% (11 of 67 patients) for the combination versus 12.1% (4 of 33 patients) for erlotinib (p = 0.77). PFS median 3.5 versus 1.9 months [HR = 0.86, 95% CI (0.52-1.43), p = 0.29] and OS median 9.5 versus 5.8 months [HR = 0.92, 95% CI (0.57-1.48), p = 0.74] numerically favored the combination. In an unplanned subset analysis, among EGFR wild type patients (n = 51), but not EGFR mutant patients (n = 17), median PFS was 3.5 versus 1.7 months [HR = 0.35, 95% CI (0.14-0.86), p = 0.02] and OS was 6.2 versus 5.2 months [HR = 0.72, 95% CI (0.35-1.48), p = 0.37] for combined therapy versus erlotinib, respectively. Notably, EGFR WT patients were more likely to be hormone receptor-positive (either estrogen receptor α- and/or progesterone receptor-positive) compared to EGFR mutant patients (50% versus 9.1%, respectively) (p = 0.03). Treatment was well tolerated with predominant grade 1-2 dermatologic and gastrointestinal adverse effects.

CONCLUSION

Addition of fulvestrant to erlotinib was well tolerated, with increased activity noted among EGFR wild type patients compared to erlotinib alone, albeit in an unplanned subset analysis.

ERβ Sensitizes NSCLC to Chemotherapy by Regulating DNA Damage Response

The expression of wild-type estrogen receptor β (ESR2/ERβ1) correlates with clinical outcome in patients with non-small cell lung cancer (NSCLC). However, the molecular mechanism that accounts for this association is currently poorly understood. ERβ1 was previously linked to chemotherapy response in patients with breast cancer and in breast cancer cells. The effect of the receptor in NSCLC cells after chemotherapy treatment, a common remedy for advanced NSCLC, has not been studied. Here, upregulation of ERβ1 increases the sensitivity of NSCLC cells to treatment with doxorubicin and etoposide. This effect was primarily observed in p53-defecient NSCLC cells. In these cells, ERβ1 either enhanced G₂-M cell-cycle arrest by activating the checkpoint kinase 1 (Chk1) and altering downstream signaling or induced apoptosis. The expression of p63 target genes that control G₂-M checkpoint activation was altered by ERβ1 suggesting an ERβ1-p63 transcriptional cooperation in lung cancer cells that affects DNA damage response (DDR). These results suggest involvement of ERβ1 in the mechanism that regulates DNA damage response in NSCLC cells and support the potential predictive and therapeutic value of the receptor in clinical management of the disease.Implications: This study demonstrating the impact of ERβ1 on chemosensitivity of NSCLC cells suggests the predictive value of the receptor for successful response of tumors to chemotherapy and the potential benefit of chemotherapy-treated patients from the use of ER ligands. Mol Cancer Res; 16(2); 233-42. ©2017 AACR.

Decreased expression of cytochrome p450 1B1 in non-small cell lung cancer

Recent studies have associated oestrogen metabolism and cigarette smoking with their carcinogenic impact on the lungs. Compounds commonly found in tobacco smoke induce the activity of CYP1B1, the enzyme responsible for the synthesis of catecholic derivatives of oestrogens. During their redox transformations, these structures can release large amounts of reactive oxygen species or can form DNA adducts, which lead to the decomposition of genetic material. This process may illustrate the synergistic effect of oestrogenic activity and tobacco combustion on oestrogen-dependant lung cancer development. There is considerable evidence suggesting that the level of oestrogen in lung tumours is elevated. Therefore, by using reverse transcription, real-time PCR and Western Blot analysis, we evaluated the CYP1B1 status in tissues from 76 patients diagnosed with non-small cell lung cancer (NSCLC) to confirm whether potential overexpression of CYP1B1 may impact lung cancerogenesis induced by oestrogens. We found significantly lower levels of CYP1B1 transcripts (p=0.00001) and proteins (p=0.000085) in lung tumour material compared to corresponding, histopathologically unchanged tissues. We also analysed the association of CYP1B1 expression with gender, age and clinicopathological data of NSCLC patients. We observed lower amounts of CYP1B1 occurring in the middle stages of LC, regardless of gender, age or histological type of lung cancer.

Sex Differences and Bone Metastases of Breast, Lung, and Prostate Cancers: Do Bone Homing Cancers Favor Feminized Bone Marrow?

Sex-associated differences in bone metastasis formation from breast, lung, and prostate cancer exist in clinical studies, but have not been systematically reviewed. Differences in the bone marrow niche can be attributed to sexual dimorphism, to genetic variations that affect sex hormone levels, or to the direct effects of sex hormones, natural or exogenously delivered. This review describes the present understanding of sex-associated and sex hormone level differences in the marrow niche and in formation of bone metastasis during the transition of these three cancers from treatable disease to an often untreatable, lethal metastatic one. Our purpose is to provide insight into some underlying molecular mechanisms for hormonal influence in bone metastasis formation, and to the potential influence of sexual dimorphism, genetic differences affecting sex assignment, and sex hormone level differences on the bone niche and its favorability for metastasis formation. We reviewed publications in PubMed and EMBASE, including full length manuscripts, case reports, and clinical studies of relevance to our topic. We focused on bone metastasis formation in breast, lung, and prostate cancer because all three commonly present with bone metastases. Several clear observations emerged. For breast cancer bone metastasis formation, estrogen receptor (ER) signaling pathways indicate a role for ER beta (ERβ). Estrogen influences the bone microenvironment, creating and conditioning a favorable niche for colonization and breast cancer progression. For lung cancer, studies support the hypothesis that females have a more favorable bone microenvironment for metastasis formation. For prostate cancer, a decrease in the relative androgen to estrogen balance or a “feminization” of bone marrow favors bone metastasis formation, with a potentially important role for ERβ that may be similar to that in breast cancer. Long-term estrogen administration or androgen blockade in males may feminize the bone marrow niche to one more favorable for bone metastases in prostate cancer. Administration of androgens in females, especially combined with mastectomy, may reduce risk of developing bone metastatic breast cancer. We conclude that it should be considered that females, those with female-leaning genetic variations, or hormonal states that feminize the bone marrow, may offer favorable sites for bone metastases.

Exploring estrogenic activity in lung cancer

It is well known that a connection between xenobiotics inhalation, especially tobacco combustion and Lung Cancer development is strongly significant and indisputable. However, recent studies provide evidence indicating that another factors such as, estrogens are also involved in lung carcinoma biology and metabolism. Although the status of estrogen receptors (ER), in both cancerous and healthy lung tissue has been well documented, there is still inconclusive data with respect of which isoform of the receptor is present in the lungs. However according to several studies, ERβ appears to be predominant form. Apart from ERs, estrogens can work through a recently discovered G-coupled estrogen receptor. Binding with both types of the receptors causes a signal, which leads to i.e. enhanced cell proliferation. There are many published reports which suggest that estrogen can be synthesized in situ in lung cancer. Some disturbances in the activity and expression levels of enzymes involved in estrogen synthesis were proved. This suggests that increased amounts of sex-steroid hormones can affect cells biology and be the reason of the accelerated development and pathogenesis of lung cancer. There also exist phenomena which associate estrogenic metabolism and tobacco combustion and its carcinogenic influence on the lungs. Compounds present in cigarette smoke induce the activity of CYP1B1, the enzyme responsible for estrogenic metabolism and synthesis of their cateholic derivatives. These structures during their redox cycle are able to release reactive oxygen species or form DNA adduct, which generally leads to destruction of genetic material. This process may explain the synergistic effect of smoking and estrogens on estrogen-dependent lung cancer development.

Association between the CYP11 family and six cancer types

Cytochromes P450 (CYPs) are a major source of variability in pharmacokinetics and drug response. CYPs utilize a variety of small and large molecules as substrates in enzymatic reactions. The CYP genes may be divided into two groups: Endogenous CYPs (CYP family 7–51) and xenobiotic CYPs (CYP family 1–4). The aim of the present study was to investigate whether endogenous CYPs exhibit similar gene expression and mutations in various cancer types. The gene expression profiles and somatic mutations exhibited in colon adenocarcinoma, kidney renal clear cell carcinoma, liver hepatocellular carcinoma, lung squamous cell carcinoma, prostate adenocarcinoma and uterine corpus endometrial carcinoma were analyzed using data obtained from The Cancer Genome Atlas. The expression of CYP11A1 was significantly downregulated in all six cancer types. In addition, CYP11B1 and CYP11B2 exhibited the highest number of mutations among endogenous CYPs in all samples. As the CYP11 family is important for steroid biosynthesis, and previous studies have demonstrated that steroid hormones are associated with certain cancers, these results indicate a common role of the CYP11 family in various cancer types.

Intra- and interspecies gene expression models for predicting drug response in canine osteosarcoma

Background

Genomics-based predictors of drug response have the potential to improve outcomes associated with cancer therapy. Osteosarcoma (OS), the most common primary bone cancer in dogs, is commonly treated with adjuvant doxorubicin or carboplatin following amputation of the affected limb. We evaluated the use of gene-expression based models built in an intra- or interspecies manner to predict chemosensitivity and treatment outcome in canine OS. Models were built and evaluated using microarray gene expression and drug sensitivity data from human and canine cancer cell lines, and canine OS tumor datasets. The “COXEN” method was utilized to filter gene signatures between human and dog datasets based on strong co-expression patterns. Models were built using linear discriminant analysis via the misclassification penalized posterior algorithm.

Results

The best doxorubicin model involved genes identified in human lines that were co-expressed and trained on canine OS tumor data, which accurately predicted clinical outcome in 73 % of dogs (p = 0.0262, binomial). The best carboplatin model utilized canine lines for gene identification and model training, with canine OS tumor data for co-expression. Dogs whose treatment matched our predictions had significantly better clinical outcomes than those that didn’t (p = 0.0006, Log Rank), and this predictor significantly associated with longer disease free intervals in a Cox multivariate analysis (hazard ratio = 0.3102, p = 0.0124).

Conclusions

Our data show that intra- and interspecies gene expression models can successfully predict response in canine OS, which may improve outcome in dogs and serve as pre-clinical validation for similar methods in human cancer research.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-016-0942-8) contains supplementary material, which is available to authorized users.

Comparative proteome analysis across non-small cell lung cancer cell lines

Non-small cell lung cancer (NSCLC) cell lines are widely used model systems to study molecular aspects of lung cancer. Comparative and in-depth proteome expression data across many NSCLC cell lines has not been generated yet, but would be of utility for the investigation of candidate targets and markers in oncogenesis. We employed a SILAC reference approach to perform replicate proteome quantifications across 23 distinct NSCLC cell lines. On average, close to 4000 distinct proteins were identified and quantified per cell line. These included many known targets and diagnostic markers, indicating that our proteome expression data represents a useful resource for NSCLC pre-clinical research. To assess proteome diversity within the NSCLC cell line panel, we performed hierarchical clustering and principal component analysis of proteome expression data. Our results indicate that general proteome diversity among NSCLC cell lines supersedes potential effects common to K-Ras or epidermal growth factor receptor (EGFR) oncoprotein expression. However, we observed partial segregation of EGFR or KRAS mutant cell lines for certain principal components, which reflected biological differences according to gene ontology enrichment analyses. Moreover, statistical analysis revealed several proteins that were significantly overexpressed in KRAS or EGFR mutant cell lines.

Overexpression of estrogen receptor beta is a prognostic marker in non-small cell lung cancer: a meta-analysis

BACKGROUND

Expression of estrogen receptor beta (ERβ) is a potentially interesting prognostic marker and therapeutic target in non-small cell lung cancer (NSCLC). Although the expression of ERβ has been reported to correlate with better prognosis of NSCLC in most literatures, some controversies still exist. Since the limited patient numbers within independent studies, here we performed a meta-analysis to clarify the correlations between ERβ expression and prognosis in NSCLC.

MATERIALS AND METHODS

We performed a final analysis of 2279 patients from 14 evaluable studies for Prognostic Value of overexpression ERβ (up to October 2014). Data from eligible studies were extracted and included into meta-analysis using a random effects model. Studies were pooled. Summary hazard ratios (HR) were calculated.

RESULTS

Our study shows that the pooled hazard ratio (HR) of overexpression ERβ for overall survival in NSCLC was 0.78 [95% confidence interval (CI): 0.62-0.98] by univariate analysis and 1.06 (95% CI: 0.70-1.61) by multivariate analysis. Pooled HR in American and Japan was 1.09 (95% CI: 0.95-1.25, P=0.239) from 6 studies reported, however, pooled HR was 0.57 (95% CI: 0.46-0.70) outside of American and Japan from 8 studies reported. Pooled HR was 0.75 (95% CI: 0.60-0.94) from 6 studies reported for N-ERβ and 0.76 (95% CI: 0.51-1.12) from 6 Studies reported for C-ERβ.

CONCLUSION

Our results suggested ERβ was significant associated with good overall survival in patients with NSCLC on univariate analysis but not multivariate analysis. ERβ expression is a good prognostic outcome outside of American and Japan. Overexpression of N-ERβ NSCLC patients had better survival. Large prospective studies are now needed to confirm the clinical utility of ERβ as an independent prognostic marker.

Increased expression of proline-, glutamic acid- and leucine-rich protein PELP1 in non-small cell lung cancer

It has been demonstrated that estrogens are able to enhance lung tumorigenesis by estrogen receptor (ER) pathway. ER signaling is a highly complex process that requires a number of different coactivators, including proline-, glutamic acid- and leucine-rich protein-1 (PELP1). We studied PELP1 transcript and protein levels in cancerous and histopathologically unchanged lung tissues obtained from 73 patients diagnosed with non-small cell lung cancer (NSCLC). We observed increased levels of PELP1 transcript (P=0.00001) and protein (P=0.00001) in tumor tissues compared to adjacent histopathologically unchanged tissues. Significant increase of PELP1 transcript/protein level was found in all patients, regardless of gender (males: P=0.0003/P=0.000003; females: P=0.0005/P=0.02), age (≤ 60 patients: P=0.042/P=0.016; >60 patients: P=0.00001/P=0.00001) or histopathological type of tumor (adenocarcinoma [ADC]: P=0.004/P=0.0006; squamous cell carcinoma [SSC]: P=0.0009/P=0.0008). Increased PELP1 transcript/protein levels were also correlated with some lung cancer stage (1a: P=0.07/P=0.02; 1b: P=0.001/P=0.03; 2a: P=0.012/P=0.001), tumor size (T2a: P=0.0006/P=0.001) and lymph node metastasis (N0: P=0.0003/P=0.0006; N1: P=0.017/P=0.003). Moreover, significant increase in PELP1 transcript level in cancer stage 1a (P=0.02) was observed. PELP1 protein content was higher in tumor tissues of patients with cancer stage 3a (P=0.04) and in T1a tumor size (P=0.03). Our studies demonstrate significantly higher amounts of PELP1 transcript and protein in tumor tissues in patients with NSCLC. Moreover, we also determined the association of PELP1 transcript and protein level with some clinicopathological features of NSCLC.

Survival in women with NSCLC: the role of reproductive history and hormone use

INTRODUCTION

Although lung cancer is the leading cause of cancer death in women, few studies have investigated the hormonal influence on survival after a lung cancer diagnosis and results have been inconsistent. We evaluated the role of reproductive and hormonal factors in predicting overall survival in women with non-small-cell lung cancer (NSCLC).

METHODS

Population-based lung cancer cases diagnosed between November 1, 2001 and October 31, 2005 were identified through the Metropolitan Detroit Surveillance, Epidemiology, and End Results Registry. Interview and follow-up data were collected for 485 women. Cox proportional hazard regression models were used to determine hazard ratios (HRs) for death after an NSCLC diagnosis associated with reproductive and hormonal variables.

RESULTS

Use of hormone therapy (HT) was associated with improved survival (HR, 0.69; 95% confidence interval, 0.54-0.89), adjusting for stage, surgery, radiation, education level, pack-years of smoking, age at diagnosis, race, and a multiplicative interaction between stage and radiation. No other reproductive or hormonal factor was associated with survival after an NSCLC diagnosis. Increased duration of HT use before the lung cancer diagnosis (132 months or longer) was associated with improved survival (HR, 0.54; 95% confidence interval, 0.37-0.78), and this finding remained significant in women taking either estrogen alone or progesterone plus estrogen, never smokers, and smokers.

CONCLUSION

These findings suggest that HT use, in particular use of estrogen plus progesterone, and long-term HT use are associated with improved survival of NSCLC.

LRIG2 expression and prognosis in non-small cell lung cancer

The human leucine-rich repeats and immunoglobulin-like domains 2 (LRIG2) protein has been shown to be of prognostic value in several types of human cancer, however, the expression profiles of LRIG2 have not been described in non-small cell lung cancer (NSCLC). The present study evaluated the mRNA expression of LRIG2 in tumor specimens obtained from 39 NSCLC patients by SYBR Green quantitative polymerase chain reaction and the protein expression of LRIG2 in formalin-fixed paraffin sections obtained from 116 NSCLC patients by immunohistochemistry. The correlations between LRIG2 expression and clinicopathological data were analyzed. The patient survival data were collected retrospectively and the possible prognostic value of LRIG2 protein expression was investigated. The results showed that the mRNA expression of LRIG2 was decreased in NSCLC cancer tissues, which was associated with histological subtypes and tumor differentiation status. The protein expression of LRIG2 was only observed in the cytoplasm of the tumor tissue, which conformed to the mRNA expression results. Furthermore, the patients with high LRIG2 cytoplasmic expression showed poor survival times, and the five-year survival rate for patients with high LRIG2 expression was 27.8%, compared with 38.8% for patients with low expression (P=0.034), indicating that LRIG2 expression levels may have a potential role in the pathogenesis of NSCLC, and also a significant prognostic value. Further studies are required to fully elucidate the exact function of LRIG2 in NSCLC.