Correlation between epidermal growth factor receptor mutations and expression of female hormone receptors in East-Asian lung adenocarcinomas

G protein-coupled estrogen receptor activates PI3K/AKT/mTOR signaling to suppress ferroptosis via SREBP1/SCD1-mediated lipogenesis

BACKGROUND

Lung cancer is the leading cause of cancer-related death worldwide. The sex differences in the occurrence and fatality rates of non-small cell lung cancer (NSCLC), along with its association with estrogen dependence, suggest that estrogen receptors (ERs) contribute to the development of NSCLC. However, the influence of G protein-coupled estrogen receptor (GPER1) on NSCLC remains to be determined. Escape from ferroptosis is one of the hallmarks of tumor discovered in recent years. In this context, the present study evaluated whether GPER1 promotes NSCLC progression by preventing ferroptosis, and the underlying mechanism through which GPER1 protects against ferroptosis was also explored.

METHODS

The effects of GPER1 on the cytotoxicity of H2O2, the ferroptosis inducer RSL3, and Erastin were assessed using the CCK8 assay and plate cloning. Lipid peroxidation levels were measured based on the levels of MDA and BODIPY™581/591C11. GPER1 overexpression and knockdown were performed and G1 was used, and the expression of SCD1 and PI3K/AKT/mTOR signaling factors was measured. Immunofluorescence analysis and immunohistochemistry were performed on paired specimens to measure the correlation between the expression of GPER1 and SCD1 in NSCLC tissues. The effect of GPER1 on the cytotoxicity of cisplatin was measured in vitro using the CCK8 assay and in vivo using xenograft tumor models.

RESULTS

GPER1 and G1 alleviated the cytotoxicity of H2O2, reduced sensitivity to RSL3, and impaired lipid peroxidation in NSCLC tissues. In addition, GPER1 and G1 promoted the protein and mRNA expression of SCD1 and the activation of PI3K/AKT/mTOR signaling. GPER1 and SCD1 expression were elevated and positively correlated in NSCLC tissues, and high GPER1 expression predicted a poor prognosis. GPER1 knockdown enhanced the antitumor activity of cisplatin in vitro and in vivo.

CONCLUSION

GPER1 prevents ferroptosis in NSCLC by promoting the activation of PI3K/AKT/mTOR signaling, thereby inducing SCD1 expression. Therefore, treatments targeting GPER1 combined with cisplatin would exhibit better antitumor effects.

Management of pulmonary nodules in women with pregnant intention: A review with perspective

The process for the management of pulmonary nodules in women with pregnant intention remains a challenge. There was a certain proportion of targeted female patients with high-risk lung cancer, and anxiety for suspicious lung cancer in early stage also exists. A comprehensive review of hereditary of lung cancer, effects of sexual hormone on lung cancer, natural history of pulmonary nodules, and computed tomography imaging with radiation exposure based on PubMed search was completed. The heredity of lung cancer and effects of sexual hormone on lung cancer are not the decisive factors, and the natural history of pulmonary nodules and the radiation exposure of imaging should be the main concerns. The management of incidental pulmonary nodules in young women with pregnant intention is an intricate and indecisive problem we have to encounter. The balance between the natural history of pulmonary nodules and the radiation exposure of imaging should be weighed.

Expression patterns and clinical significance of estrogen receptor in non-small cell lung cancer

BACKGROUND

Lung cancer death remains the highest among all malignancies. Gender differences show women have an increased cancer incidence while men have worse outcomes. These observations identified that some lung carcinomas express estrogen receptors (ER). This is a promising target as antiestrogen drugs can reduce tumors and improve survival. However, there is a limited understanding of ER distribution and its clinical significance to properly design antiestrogen drug clinical trials. Thus, we comprehensively analyzed ERα and ERβ expression patterns by gender, cancer cell type, and receptor location in lung cancer.

METHODS

We conducted a systematic review using the PubMed database from all-time through October 2022, using MeSH terms with the keywords "lung cancer," "estrogen receptor," and "immunohistochemistry." We identified 120 studies with 21 reports being evaluated based on our inclusion criteria.

RESULTS

We examined 4874 lung cancers from 5011 patients. ERβ is the predominant form of ER expressed, mainly found in the nucleus. The ERβ positivity rate is 51.5% in males versus 55.5% in females and was not statistically different. In contrast, ERα is predominately extranuclear in location, and ERα expression varies by gender. Males had a positivity rate of 31% versus 26.6% in females, which is statistically different. ERα is associated with a worse prognosis in some studies, while it had no effect in others. Overall, ERβ was associated with a better prognosis.

CONCLUSION

We characterized ER expression patterns in 4874 lung cancers. Over 50% expressed ERβ with equal rates in both sexes and was associated with a better prognosis. ERα expression was slightly higher in males (31%) than females (26.6%) and was associated with a poor prognosis. Our findings suggest estrogen signaling may be a promising drug target in lung cancer.

Role of GPER1 in the Mechanism of EGFR-TKIs Resistance in Lung Adenocarcinoma

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) have a good clinical efficacy in lung adenocarcinoma harboring activating-mutation EGFR. Such EGFR mutations are more frequently observed in women and non-smokers. EGFR mutations are frequently reported to correlate with estrogen receptor (ER) α and/or β-expressions in lung adenocarcinoma. However, the role of GPER1, a novel G-protein-coupled estrogen receptor, in the estrogen signaling pathway and the association between its expression and EGFR mutation in lung adenocarcinoma are less well understood. Here, we aimed to examine ERα, Erβ, and GPER1 expressions, and to analyze their roles in the mechanism of EGFR-TKIs resistance in lung adenocarcinoma. We report an enhanced cytoplasmic expression of GPER1 in tissue samples. The nuclear GPER1 positively correlated with ER expression while the nuclear and also cytoplasmic expressing GPER1 negatively correlated with ER expression. Further, TKI resistance results in higher cytoplasmic GPER1 expression and decreased ER and nuclear GPER1 expression with evidence for GPER1 translocation to cell surface during the resistance. GPER1 itself is capable of regulating ER expression with concomitant regulation of MAPK signaling, and co-inhibition of GPER1 and ERs attenuates ERK1/2 and Akt phosphorylation. The results were also verified in vivo in mice where GPER1 silencing slowed tumor progression which was further potentiated by gefitinib.

Upregulation of estrogen receptor beta protein but not mRNA predicts poor prognosis and may be associated with enhanced translation in non-small cell lung cancer: a systematic review and meta-analysis

Background

An increasing number of original studies suggest that estrogen receptor beta (ERβ) expression may be related to non-small cell lung cancer (NSCLC) prognosis; however, the evidence remains inconclusive and conflicting. We aimed to systematically evaluate the expression and prognostic value of ERβ in NSCLC, and to explain the inconsistency between ERβ protein and mRNA level.

Methods

PubMed, Embase, and Web of Science databases were searched for studies (published before October 6, 2020) reporting the prognostic value of ERβ protein expression in NSCLC. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) for overall survival (OS) were calculated. Transcriptome and survival data of lung adenocarcinoma patients were obtained from public databases for differential expression and survival analyses. Immunohistochemistry (IHC) was performed to examine the ERβ protein expression in 39 NSCLC patients. Western blotting and RT-qPCR were performed to analyze ERβ expression in two paired NSCLC and normal adjacent tissue samples. The effect of methyltransferase-like 13 (METTL3) on ERβ expression was investigated in a lung cancer cell line.

Results

Meta-analysis of 23 studies with a total of 3744 patients demonstrated that high protein expression of overall ERβ and cytoplasmic ERβ indicated poor OS (HR: 1.05, 95% CI: 1.00 to 1.10; HR: 1.48, 95% CI: 1.13 to 1.95) in NSCLC. For lung adenocarcinoma especially, high protein expression of both overall/cytoplasmic ERβ and nuclear ERβ suggested poor OS (HR: 1.54, 95% CI: 1.05 to 2.25; HR: 1.36, 95% CI: 1.03 to 1.80). Bioinformatics analysis indicated the expression of ERβ mRNA was not associated with the prognosis of lung adenocarcinoma. Analysis of public databases showed that ERβ mRNA is not highly expressed in tumor tissues, however, IHC results revealed that ERβ protein is highly expressed in NSCLC tissues. We validated this inconsistency in ERβ expression in paired tumors and normal adjacent tissues from patients. Moreover, METTL3 knockdown in the A549 cell line downregulated ERβ protein expression but not ERβ mRNA expression.

Conclusions

Our study elucidated the inconsistency between ERβ protein and mRNA expression levels and their prognostic values. The results indicated that METTL3-driven enhanced translation in NSCLC may cause this inconsistency.

Hormonal factors in association with lung cancer among Asian women: A pooled analysis from the International Lung Cancer Consortium

Two thousand sixty-four lung cancer cases and 5342 controls were evaluated in this International Lung Cancer Consortium (ILCCO) pooled analysis on estrogen-related hormonal factors and lung cancer in Asian women. Random effect of study site and fixed effect of age, smoking status, comprehensive smoking index and family history of lung cancer were adjusted for in the multivariable logistic regression models. We found that late onset of menarche conferred elevated odds of lung cancer with adjusted odds ratio (OR) of 1.24 (95% confidence interval [CI] = 1.05, 1.45) for 17 years or older, compared to 14 years or younger. Late onset of menopause at 55 years old or older was associated with lung cancer with OR = 1.24 (95% CI = 1.02, 1.51). Nonnatural menopause was associated with an OR of 1.39 (95% CI = 1.13, 1.71). More live births showed reversed association with lung cancer (ORs of 5 or more live births: 0.71 (95% CI = 0.60, 0.84), compared to 0-2 live births (P_trend < 0.001). A later first child delivery seemed associated with an increased susceptibility: OR of 21 to 25 years old: 1.23 (95% CI = 1.06, 1.40), 26 or older: 1.27 (95% CI = 1.06, 1.52), P_trend = .010). The use of oral contraceptives appeared to be protective with an OR of 0.69 (95% CI = 0.57, 0.83). Stronger for adenocarcinoma than squamous cell carcinoma, these relationships were not clearly modified by smoking status, probably because of lower prevalence of smoking. This is a first and largest pooling study of lung cancer among Asian women and the results suggested potential roles of hormone-related pathways in the etiology of this disease.

A practical and adaptive approach to lung cancer screening: a review of international evidence and position on CT lung cancer screening in the Singaporean population by the College of Radiologists Singapore

Lung cancer is the leading cause of cancer-related death around the world, being the top cause of cancer-related deaths among men and the second most common cause of cancer-related deaths among women in Singapore. Currently, no screening programme for lung cancer exists in Singapore. Since there is mounting evidence indicating a different epidemiology of lung cancer in Asian countries, including Singapore, compared to the rest of the world, a unique and adaptive approach must be taken for a screening programme to be successful at reducing mortality while maintaining cost-effectiveness and a favourable risk-benefit ratio. This review article promotes the use of low-dose computed tomography of the chest and explores the radiological challenges and future directions.

The prevalence and prognostic significance of estrogen receptor beta expression in non-small cell lung cancer

Background

Estrogen receptor beta (ERβ) is the predominant estrogen receptor (ER) expressed in non-small cell lung cancer (NSCLC); however, due to methodological disparities among prior studies, the prognostic value of ERβ expression in NSCLC remains unclear. Our objective was to apply improved detection and analysis techniques to assess the prognostic value of ERβ expression in NSCLC.

Methods

A tissue microarray (TMA) was used which contained resected and biopsy specimens from 299 patients diagnosed at a single center with stages I-IV NSCLC. Sections of this array were stained using high-sensitivity fluorescence immunohistochemistry, with the well-validated PPG5/10 monoclonal antibody. Digital images of the stained array slides were analyzed using software-based image analysis, which reported ERβ expression as a continuous variable in different subcellular domains.

Results

There were no differences in ERβ expression between male and female patients. High expression of ERβ was not a prognostic factor, but was significantly associated with stage IV disease in both tumor and stroma (P<0.001). In multivariable analysis, a high nuclear/cytoplasmic (N/C) ratio of ERβ expression was significantly associated with shorter overall survival, based on expression in the tumor [hazard ratio (HR): 1.65; 95% confidence interval (CI): 1.25-2.19; P<0.001] and in the stroma (HR: 1.57; 95% CI: 1.16-2.12; P=0.003).

Conclusions

These results suggest that subcellular localization of ERβ, but not absolute expression, is a prognostic factor in NSCLC.

The prognostic factors of recurrence and survival in female patients with lung adenocarcinoma and breast cancer

BACKGROUND

The aim of this study was to verify the predictors of recurrence and survival in lung adenocarcinoma patients with experiences of breast cancer therapies.

METHODS

We retrospectively reviewed consecutive patients who were treated at our hospital for lung adenocarcinoma from 2004/01 to 2014/03. The patients were divided into groups of those with lung adenocarcinoma alone and those with lung and breast cancer. Kaplan-Meier plots and log-rank tests were used to estimate outcomes.

RESULTS

54 patients with lung adenocarcinoma and breast cancer were compared with 457 patients with single primary lung adenocarcinomas. After propensity score matching with control of age, operation type, smoking status and pathologic stage, tumor differentiation, recurrence rate and tumor size were significantly different between two groups. The significant predictors for recurrence included undergone chemotherapy (HR = 25, p < 0.001), moderate/poor differentiation (HR = 8.125, p = 0.012), tumor size ≧ 2 cm (HR = 15, p < 0.001), LVSI (HR = 13.67, p = 0.031) and GGO ratio < 50% (HR = 14.667, p = 0.014). The significant prognostic factors for survival were accepted chemotherapy (HR = 6.182, p = 0.021), LVSI (HR = 22, p = 0.012) and GGO ratio < 50% (HR = 9.143, p = 0.045). Kaplan-Meier analysis revealed that patients with lung adenocarcinoma and breast cancer had a better 5-year disease-free survival (p = 0.009), while the Her2-negative patients obtained a better overall survival (p = 0.038).

CONCLUSIONS

In patients with breast cancer and lung adenocarcinoma, independent risk factors of recurrence were undergone chemotherapy, moderate/poor differentiation, tumor size ≧ 2 cm, LVSI and GGO ratio < 50%. Only undergone chemotherapy, LVSI and GGO ratio < 50% were significant poor predictors for survival. However, patients with metachronous lung adenocarcinoma and breast cancer had better disease-free survival and less tumor recurrence than patients with lung adenocarcinoma alone.

Expression of female sex hormone receptors and its relation to clinicopathological characteristics and prognosis of lung adenocarcinoma

BACKGROUND

Adenocarcinoma (ADC) of the lung exhibits different clinicopathological characteristics in men and women. Recent studies have suggested that these differences originate from the expression of female sex hormone receptors in tumor cells. The aim of the present study was to evaluate the immunohistochemical expression of female sex hormone receptors in lung ADC and determine the expression patterns in patients with different clinicopathological characteristics.

METHODS

A total of 84 patients with lung ADC who underwent surgical resection and/or core biopsy were recruited for the present study. Immunohistochemical staining was performed for estrogen receptor α (ERα), estrogen receptor β (ERβ), progesterone receptor (PR), epidermal growth factor receptor (EGFR), EGFR E746- A750 del, and EGFR L858R using tissue microarray.

RESULTS

A total of 39 (46.4%) ERα-positive, 71 (84.5%) ERβ-positive, and 46 (54.8%) PR-positive lung ADCs were identified. In addition, there were 81 (96.4%) EGFR-positive, 14 (16.7%) EGFR E746-A750 del-positive, and 34 (40.5%) EGFR L858R-positive cases. The expression of female sex hormone receptors was not significantly different in clinicopathologically different subsets of lung ADC.

CONCLUSIONS

Expression of female sex hormone receptors is not associated with the prognosis and clinicopathological characteristics of patients with lung ADC.

Smoking, Sex, and Non-Small Cell Lung Cancer: Steroid Hormone Receptors in Tumor Tissue (S0424)

Background

To what extent steroid hormones contribute to lung cancer in male and female never smokers and smokers is unclear. We examined expression of hormone receptors in lung tumors by sex and smoking.

Methods

Patients with primary non-small cell lung cancer were recruited into an Intergroup study in the United States and Canada, led by SWOG (S0424). Tumors from 813 cases (450 women and 363 men) were assayed using immunohistochemistry for estrogen receptor (ER)-α, ER-β, progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Linear regression was used to examine differences in expression by sex and smoking status. Cox proportional hazard models were used to estimate survival associated with the receptors. All statistical tests were two-sided.

Results

In ever smokers, postmenopause and oral contraceptive use were associated with lower nuclear ER-β (P = .02) and total (nuclear + cytoplasmic) PR expression (P = .02), respectively. Women had lower cytoplasmic ER-α (regression coefficient [β], or differences in H-scores = -15.8, P = .003) and nuclear ER-β (β = -12.8, P = .04) expression than men, adjusting for age, race, and smoking. Ever smokers had both higher cytoplasmic ER-α (β = 45.0, P < .001) and ER-β (β = 25.9, P < .001) but lower total PR (β = -42.1, P < .001) than never smokers. Higher cytoplasmic ER-α and ER-β were associated with worse survival (hazard ratio = 1.73, 95% confidence interval [CI] = 1.15 to 2.58, and HR = 1.59, 95% CI = 1.08 to 2.33, respectively; quartiles 4 vs 1).

Conclusions

Lower expression of nuclear ER-β in women supports the estrogen hypothesis in lung cancer etiology. Increasing cytoplasmic ER-α and ER-β and decreasing PR protein expression may be mechanisms whereby smoking disrupts hormone pathways.

Epidermal Growth Factor Receptor Mutation Frequency in Squamous Cell Carcinoma and Its Diagnostic Performance in Cytological Samples: A Molecular and Immunohistochemical Study

Background

Epidermal growth factor receptor (EGFR) mutation is the most frequent mutation tested in lung cancer for targeted therapy in the era of personalized medicine. Knowledge about EGFR mutation is constantly expanding regarding its frequency, clinicopathological association, advancements in testing methodology and sample requirement. We investigated EGFR mutation frequency in non-small cell lung cancer (NSCLC) in North Indian patients and evaluated its diagnostic performance in cytological samples.

Methods

Molecular EGFR testing was done in 250 cases of NSCLC by both real-time polymerase chain reaction (PCR) (Therascreen) and mutation-specific EGFR immunohistochemistry (IHC). Thirty cases had both cytology samples and biopsy including 20 pleural effusions and 10 fine-needle aspirates. EGFR mutation concordance between pleural effusion and biopsy was studied.

Results

EGFR mutation was overall 31.6% in NSCLC with 36.5% in adenocarcinoma and 15% in squamous cell carcinoma. L858R mutation accounted for 50.7% and DEL19 for 39.3% of total EGFR mutations. Complex mutations were seen in 2% of cases. Sensitivity of mutation-specific EGFR IHC was 48.3% and specificity was 92.3%. L858R showed higher sensitivity (55% vs. 33.3%) but similar specificity (93.2% vs. 91.3%) compared to DEL19. EGFR mutation was successful in 95% of pleural effusion and showed 83.3% concordance with tissue biopsy.

Conclusions

EGFR mutation frequency in North Indian patients was comparable to that of Asia-Pacific region and showed a similar pattern of histological distribution. EGFR mutation in squamous cell carcinomas is increasingly recognized which was 15% in our study. Mutation-specific EGFR IHC shows variable but generally low sensitivity and considering its significant pre- and post-analytical variables, it should be highly discouraged in patient management. Cytological samples may not only serve as suitable alternative but may be complementary to tissue biopsies.

Cytoplasmic expression of estrogen receptor β may predict poor outcome of EGFR-TKI therapy in metastatic lung adenocarcinoma

There is growing evidence that estrogen receptors (ER) are expressed in lung cancer cells, and are able to interact with the epidermal growth factor receptor (EGFR) signaling pathway. However, data on the association between cytoplasmic ER expression and the response to EGFR-tyrosine kinase inhibitors (TKI) treatment are limited. The aim of the present study was to investigate the associations between ERα/ERβ expression and EGFR mutational status and response to TKI treatment in metastatic lung adenocarcinoma. A retrospective study of 126 consecutive patients with lung adenocarcinoma who were diagnosed with stage IV disease and had received EGFR-TKI treatment was conducted. ER expression was detected by immunohistochemistry. EGFR and GTPase KRas (KRAS) mutational statuses were evaluated by denaturing high performance liquid chromatography and PCR-restriction fragment length polymorphism, respectively. In the overall cohort of 126 lung adenocarcinoma samples analyzed, ERα expression in the nucleus of tumor cells was identified in 17 (18.9%) patients, whereas ERβ expression was identified in the nucleus (22/126, 17.5%) and cytoplasm (17/126, 13.5%). The nuclear expression of ERβ was positively associated with the degree of tumor differentiation (P=0.010). EGFR-sensitizing mutations were significantly associated with improved objective response rates (ORR), disease control rates (DCR), median progression-free survival (mPFS) and median overall survival (mOS) (P<0.001; P<0.001; P=0.003; and P=0.026, respectively). Patients with cytoplasmic ERβ expression exhibited non-significant poorer ORR, DCR, mPFS and mOS compared with patients without cytoplasmic ERβ expression (P=0.082; P=0.106; P=0.084; and P=0.119, respectively). However, the significant decrease of ORR, DCR and mPFS was observed in patients with coexisting cytoplasmic ERβ expression and EGFR-sensitizing mutations (P=0.030; P=0.009; and P=0.018, respectively) in comparison with the subgroup with EGFR sensitizing mutations but negative expression of cytoplasmic ERβ. A trend towards shorter mOS was also observed in patients with coexisting cytoplasmic ERβ expression and EGFR-sensitizing mutations (P=0.071). No KRAS mutations were identified in patients with cytoplasmic ERβ expression. Subsequent to adjusting for sex, smoking status and EGFR mutation status, the Cox repression analysis indicated that cytoplasmic expression of ERβ was a negative independent predictor for mPFS in the whole patient cohort (HR=1.870; 95% confidence interval 1.058–3.305; P=0.031). Cytoplasmic ERβ expression was negatively correlated with the efficacy of EGFR-TKI treatment for metastatic lung adenocarcinoma, particularly for patients with coexisting cytoplasmic ERβ expression and EGFR-sensitizing mutations. Cytoplasmic ERβ may be a promising marker to predict the outcome of EGFR-TKI treatment.

Hormonal receptors in lung adenocarcinoma: expression and difference in outcome by sex

Background

Lung cancer seems to have different epidemiological, biomolecular and clinical characteristics in females than in males, with a better prognosis for women. The aim of the study is to determine gender differences in lung adenocarcinoma in terms of androgen (AR), estrogen (ER)α and progesterone (PgR) receptors expression and their impact on outcome.

Results

Overall survival was significantly better in ERα and in PgR positive lung adenocarcinoma patients (median survival 45 vs. 19 months).

Eight out of 62 patients showed positive expression of nuclear (n) AR and 18 of cytoplasmic (c) AR with a significantly better survival (49 vs. 19 and 45 vs. 19 months, respectively). There was a significant difference in survival between patients with vs. without c-AR expression (30 vs. 17 months). Finally, in the subgroup of women, median survival was greater in positive expression of c-AR than for women with negative c-AR (45 vs. 21 months).

Materials and Methods

We conducted an analysis on a cohort of 62 patients with advanced NSCLC treated at our institution. We investigated the immunohistochemical expression of n/c AR, ERα and PgR in 62 NSCLC and we correlated it with patients' clinic-pathologic characteristics and with prognosis.

Conclusions

Our results showed that the positive expression of one hormonal receptor could represent a prognostic factor.

Furthermore our study suggests that AR should become object of close examination in a larger series of lung adenocarcinoma patients, also for selection of the patients with best prognosis that can perform more chemotherapy lines.

Correlation between epidermal growth factor receptor mutations and the expression of estrogen receptor-β in advanced non-small cell lung cancer

Epidermal growth factor receptor (EGFR) mutations are more common in non-small cell lung cancer (NSCLC) and in female patients of East Asian origin. Therefore, the present study investigated the presence of EGFR mutations in advanced NSCLC, and assessed its correlation with clinicopathologic factors, including the expression of estrogen receptor-β (ER-β) and patient prognosis. The present study performed a retrospective analysis of 83 patients with stage IIIB-IV NSCLC. The expression of ER-β and p53 were examined using immunohistochemical methods. EGFR mutations were evaluated using the amplification refractory mutation system. The expression of ER-β and p53 were detected in 37 (45.6%) and 48 (57.8%) of the patient tumors, respectively. EGFR mutations were identified in 36 (45.4%) cases. EGFR mutations were more frequently observed in ER-β-negative tumors (26/46; 56.5%), compared with ER-β-positive tumors (10/37; 27%). The expression of ER-β was significantly associated with EGFR mutations with an odds ratio (OR) of 0.241 (P=0.029). However, no significant correlation was observed between the expression of p53 and mutations in EGFR (OR=1.792; P=0.340). In addition, the expression of ER-β and lymph node metastasis were associated with poor prognosis, whereas EGFR mutations were significantly associated with favorable prognosis in terms of progression-free survival rates. However, there was no prognostic significance associated with the expression of p53. In conclusion, the expression of ER-β was significantly correlated with the presence of EGFR mutations. The expression of ER-β and mutations of EGFR were found to be prognostic factors for survival rates in patients with advanced NSCLC.

Nuclear estrogen receptor-α expression is an independent predictor of recurrence in male patients with pT1aN0 lung adenocarcinomas, and correlates with regulatory T-cell infiltration

Background

Tumor biology of estrogen receptor-α (ERα) and progesterone receptor (PR) has been studied in breast cancers. However, clinical impact in lung cancer remains controversial. In our study, we investigate whether ERα and PR expression predicts disease recurrence and correlates with immunologic factors in stage I lung adenocarcinoma.

Methods

We reviewed patients with pathologic stage I resected lung adenocarcinoma. Tumors were classified according to the IASLC/ATS/ERS classification. Immunostaining of ERα and PR was performed using tissue microarrays (n = 913). Immunostaining of CD3+ and forkhead box P3 (FoxP3)+ lymphocyte infiltration, interleukin-7 receptor (IL-7R), and IL-12Rβ2 were performed. Cumulative incidence of recurrence (CIR) analysis was used to estimate probability of recurrence.

Results

Nuclear ERα expression was observed in 157 (17%) patients and presented more frequently in females (P = 0.038) and smaller tumors (P = 0.019). Nuclear ERα expression was not identified in mucinous tumors. In pT1a patients, 5-year CIR of patients with ERα-positive tumors was significantly higher (5-year CIR, 20%) than those with ERα-negative tumors (8%; P = 0.018). This difference was statistically significant in males (P = 0.003) but not females (P = 0.55). On multivariate analysis, nuclear ERα expression was an independent predictor of recurrence (hazard ratio = 2.27; P = 0.030). In pT1a patients, nuclear ERα expression positively correlated with tumoral FoxP3+ lymphocytes (P < 0.001), FoxP3/CD3 index (P < 0.001), and IL-7R (P = 0.022).

Conclusions

Nuclear ERα expression is an independent predictor of recurrence in pT1a lung adenocarcinomas and correlates with poor prognostic immune microenvironments.

Progesterone receptor (PR) polyproline domain (PPD) mediates inhibition of epidermal growth factor receptor (EGFR) signaling in non-small cell lung cancer cells

Recent evidence has suggested a possible role for progesterone receptor (PR) in the progression of non-small cell lung cancer (NSCLC). However, little is known concerning roles of PR in NSCLC. PR contains a polyproline domain (PPD), which directly binds to the SH3 domain of signaling molecules. Because PPD-SH3 interactions are essential for EGFR signaling, we hypothesized that the presence of PR-PPD interfered with EGFR-mediated signaling and cell proliferation. We examined the role of PR-PPD in cell proliferation and signaling by stably expressing PR-B, or PR-B with disrupting mutations in the PPD (PR-BΔSH3), from a tetracycline-regulated promoter in A549 NSCLC cells. PR-B dose-dependently inhibited cell growth in the absence of ligand, and progestin (R5020) treatment further suppressed the growth. Treatment with RU486 abolished PR-B- and R5020-mediated inhibition of cell proliferation. Expression of PR-BΔSH3 and treatment with R5020 or RU486 had no effect on cell proliferation. Furthermore, PR-B expression but not PR-BΔSH3 expression reduced EGF-induced A549 proliferation and activation of ERK1/2, in the absence of ligand. Taken together, our data demonstrated the significance of PR extranuclear signaling through PPD interactions in EGFR-mediated proliferation and signaling in NSCLC.

Correlation between epidermal growth factor receptor mutations and nuclear expression of female hormone receptors in non-small cell lung cancer: a meta-analysis

BACKGROUND

Compared with male, female non-small cell lung cancer (NSCLC) patients have better response when treated with epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs), suggesting a potential association between female hormones and EGFR mutation. However, the results provided by previous studies were inconclusive and controversial. We sought to examine the link between the expression of nuclear female hormone receptors and EGFR mutations in NSCLC.

METHODS

Electronic databases were used to search the relevant articles. The involved hormone receptors included estrogen receptor (ER) and progesterone receptor (PR). The primary endpoint was the occurrence of ER/PR expression and EGFR mutation in NSCLC patients.

RESULTS

Five studies fulfilled the criteria and were included in our analysis. Patients with high ER-β expression had higher positive EGFR mutation than low ER-β patients (44.2% vs. 23.7%), and there was a significant difference between the two groups [odds radio (OR) 3.44, 95% confidence interval (CI): 2.40-4.93, Z=6.72, P<0.001]. However, there is no significant correlation between EGFR mutations and ER-α (when included ER-α3, OR 1.20, 95% CI: 0.62-2.33, Z=0.55, P=0.58; and when included ER-α4, OR 1.18, 95% CI: 0.62-2.25, Z=0.51, P=0.61) or PR (OR 1.29, 95% CI: 0.40-4.10, Z=0.43, P=0.67). No significant publication bias was observed.

CONCLUSIONS

High nuclear expression of ER-β, but not ER-α or PR is correlated with EGFR mutations in NSCLC. The underlying mechanism and potential translational relevance warrant further investigation.

Potential therapeutic benefit of combining gefitinib and tamoxifen for treating advanced lung adenocarcinoma

Introduction. Epidermal growth factor receptor (EGFR) mutations are known as oncogene driver mutations and with EGFR mutations exhibit good response to the EGFR tyrosine kinase inhibitor Gefitinib. Some studies have shown that activation of estrogen and estrogen receptor α or β (ERα/β) promote adenocarcinoma. We evaluated the relationship between the two receptors and the potential therapeutic benefit with Gefitinib and Tamoxifen. Methods. We assessed the association between EGFR mutations as well as ERα/β expression/location and overall survival in a cohort of 55 patients with LAC from a single hospital. PC9 (EGFR exon 19 deletion mutant; Gefitinib-vulnerable cells) and A549 (EGFR wild type; Gefitinib-resistant cells) cancer cells were used to evaluate the in vitro therapeutic benefits of combining Gefitinib and Tamoxifen. Results. We found that the cytosolic but not the nuclear expression of ERβ was associated with better OS in LAC tumors but not associated with EGFR mutation. The in vitro study showed that combined Gefitinib and Tamoxifen resulted in increased apoptosis and cytosolic expression of ERβ. In addition, combining both medications resulted in reduced cell growth and increased the cytotoxic effect of Gefitinib. Conclusion. Tamoxifen enhanced advanced LAC cytotoxic effect induced by Gefitinib by arresting ERβ in cytosol.

Women and lung cancer: what is new?

In the last 20 years, there has been an increased focus on gender differences in health and disease. The earliest studies of lung cancer enrolled mainly men, as the incidence of lung cancer among women was exceedingly low. As social patterns changed around World War II and women began to smoke more, the epidemiology of lung cancer has changed. The higher percentage of lung cancer in nonsmoking women as compared with nonsmoking men suggests that lung cancer behaves differently in women. Studies of lung cancer in women indicate that there are differences in risk factors, histology, pathophysiology, treatment outcomes, and prognosis as compared with men. The purpose of this review is to provide a concise summary of the literature on lung cancer as it pertains to women, with an emphasis on new areas of research and treatment options.

Estrogen signaling in lung cancer: an opportunity for novel therapy

Lung cancer is the leading cause of cancer death in U.S. and represents a major public health burden. Epidemiologic data have suggested that lung cancer in women may possess different biological characteristics compared to men, as evidenced by a higher proportion of never-smokers among women with lung cancer. Emerging data indicate that female hormones such as estrogen and progesterone play a significant role in lung carcinogenesis. It has been reported that estrogen and progesterone receptors are expressed in lung cancer cell lines as well as in patient-derived tumors. Hormone related risk factors such as hormone replacement therapy have been implicated in lung carcinogenesis and several preclinical studies show activity of anti-estrogen therapy in lung cancer. In this review, we summarize the emerging evidence for the role of reproductive hormones in lung cancer and implications for lung cancer therapy.

Role of hormone receptor expression in patients with advanced-stage lung cancer treated with chemotherapy

BACKGROUND

Evidence that supports a role for hormonal status in lung cancer has been inconsistently reported and is still unclear. We retrospectively assessed the potential correlation between sex-linked hormone receptor expression and the clinical outcome of patients with advanced-stage lung cancer treated with chemotherapy.

PATIENTS AND METHODS

Based on tissue availability, 130 consecutive patients diagnosed at San Luigi Hospital from January 2008 to June 2010 were collected, including 24 small-cell lung cancer, 57 adenocarcinomas, 34 squamous cell carcinomas, 5 large-cell carcinomas, and 10 non-small-cell lung cancer-not otherwise specified. The immunohistochemical expression of estrogen receptors (ER-α and ER-β) and progesterone receptor, aromatase, epidermal growth factor receptor (EGFR), and excision repair cross-complementing 1 (ERCC1) was assessed.

RESULTS

ER-β nuclear expression was higher than ER-α and progesterone receptor, whose expression was null or weak (mainly in women). ER-β expression was significantly higher in patients with metastatic disease compared with all other disease stages (P = .02). EGFR expression was strongly correlated with non-small-cell lung cancer histology, being higher in squamous types and stage related. In men, aromatase positive cases had a worse outcome (P = .03) as well as in men with non-small-cell lung cancer and high ER-β expression. In the latter group, the combined aromatase negative and/or low ER-β expression and low ERCC1 and/or low ER-β expression showed a better outcome (P = .026; P = .03, respectively).

CONCLUSION

In patients with advanced-stage lung cancer treated with chemotherapy, the prognostic and predictive role of sex-linked hormone receptor expression, if any, is of borderline significance and is restricted to selected subgroups of patients.

Activation of the signal transducer and activator of transcription 3 pathway up-regulates estrogen receptor-beta expression in lung adenocarcinoma cells

Estrogens contribute to the pathogenesis of female lung cancer and function mainly through estrogen receptor-β (ERβ). However, the way in which ERβ expression is regulated in lung cancer cells remains to be explored. We have found that signal transducer and activator of transcription 3 (Stat3) activation up-regulates ERβ expression in PC14PE6/AS2 lung cancer cells in a preliminary Affymetrix oligonucleotide array study, and we sought to confirm the findings. In this study, we show that IL-6 induced ERβ mRNA and protein expression in lung cancer cells. The induction of ERβ in response to IL-6 was abolished by Janus kinase 2 inhibitor-AG490, dominant-negative mutant of Stat3, and Stat3-targeting short interfering RNA. The luciferase reporter assay and chromatin immunoprecipitation assay confirmed that IL-6-activated Stat3 binds to the ERβ promoter. Besides the Janus kinase 2/Stat3 pathway, the MEK/Erk pathway contributes to ERβ up-regulation induced by IL-6; however, the phosphoinositide 3'-kinase/Akt pathway does not. We also found that epidermal growth factor (EGF) stimulation or L858R mutation in EGF receptor (EGFR) induced Stat3 activation as well as ERβ expression in lung cancer cells. Inhibiting Stat3 activity by pharmacological or genetic approaches reduced EGF- and L858R mutant EGFR-induced ERβ expression, indicating that Stat3 activation is required for EGFR signaling-mediated ERβ up-regulation. Silencing ERβ decreased cell proliferation in lung cancer cells that overexpress L858R mutant EGFR. In conclusion, we have identified that Stat3 activation is essential for ERβ induction by IL-6, EGF, and the presence of EGFR mutation. The findings shed light on new therapeutic targets for female lung cancer, especially for those with EGFR mutations.

Combined analysis of estrogen receptor beta-1 and progesterone receptor expression identifies lung cancer patients with poor outcome

PURPOSE

Steroid hormones and growth factors affect lung cancer, and it is possible they act in concert to influence patient outcome.

EXPERIMENTAL DESIGN

Primary lung tumors and normal lung tissue were analyzed for expression and localization of estrogen receptor α and β-1 (ERα and ERβ), aromatase, progesterone receptor (PR), and epidermal growth factor receptor (EGFR).

RESULTS

Tumors expressed higher levels of ERβ compared to matched normal lung, whereas the reverse was true of PR. High cytoplasmic ERβ expression was identified as an independent negative prognostic predictor of overall survival (OS; HR = 1.67), and low total PR was identified as an independent negative predictor of time to progression (TTP; HR = 1.59). After adjusting for stage, age, sex, and smoking, combined high cytoplasmic ERβ and low total PR showed enhanced effects on OS (HR = 2.64) and on TTP (HR = 6.02). Further effects on OS were observed when EGFR expression was included (HR = 5.32). Patients with low cytoplasmic ERβ, low aromatase, low EGFR, and high total PR had shorter OS than patients with the opposite pattern (HR = 6.60). Contribution of these markers to survival showed no significant sex differences in a multivariable model. ERα was elevated in tumors but was not predictive of survival, and appears to represent a variant ERα protein that is only recognized by a C-terminal antibody.

CONCLUSIONS

Hormonal and EGFR pathways together may contribute to lung cancer prognosis. Lung tumors with high ERβ-1/low PR may define patients with aggressive biology. A validation study is necessary to fully assess the predictive value of these markers.

Non-small cell lung cancer in stages I-IIIB: Long-term results of definitive radiotherapy with doses ≥ 80 Gy in standard fractionation

PURPOSE

To investigate therapeutic outcome of dose escalation ≥ 80 Gy in nonresected non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

124 consecutive patients with histologically/cytologically proven NSCLC were enrolled. Tumor stage I, II, IIIA, and IIIB was diagnosed in 30, eight, 39, and 47 patients, respectively. 38 patients (31%) had weight loss > 5% during the 3 months before diagnosis. A median dose of 88.2 Gy (range 80.0-96.0 Gy), 69.3 Gy (63.0-88.0 Gy) and 56.7 Gy was applied to primary lesions, involved lymph nodes, and elective nodes (within a region of about 6 cm cranial to macroscopically involved nodes), respectively. Daily fractional ICRU doses of 2.0-2.2 Gy were delivered by the conformal target-splitting technique. 58 patients (47%) received induction chemotherapy, in median two cycles prior to radiotherapy.

RESULTS

Median follow-up time of all patients was 19 months, of patients alive 72.4 months (69-121 months). The cumulative actual overall survival rate at 2 and 5 years amounts to 39% and 11.3%, respectively, resulting in a median overall survival time of 19.6 months. According to stages I, II, IIIA, and IIIB, the median overall survival times are 31.8, 31.4, 19.0, and 14.5 months, respectively. The locoregional tumor control rate at 2 years is 49%. Apart from one treatment-related death (pneumonitis), acute toxicity according to EORTC/RTOG scores was moderate: lung grade 2 (n = 7), grade 3 (n = 3); esophagus grade 1 (n = 11); heart grade 3 (n = 1, pericarditis). No late toxicity grade > 1 has been observed.

CONCLUSION

Sequential, conventionally fractionated high-dose radiotherapy by conformal target splitting is well tolerated. The results for survival and locoregional tumor control seem to at least equalize the outcome of simultaneous chemoradiation approaches, which, at present, are considered "state of the art" for patients with nonresected NSCLC. A higher potential of radiation therapy might be reached by accelerated fractionation regimens.