C-Myc protein expression indicates unfavorable clinical outcome in surgically resected small cell lung cancer

BACKGROUND

By being highly involved in the tumor evolution and disease progression of small cell lung cancer (SCLC), Myc family members (C-Myc, L-Myc, and N-Myc) might represent promising targetable molecules. Our aim was to investigate the expression pattern and prognostic relevance of these oncogenic proteins in an international cohort of surgically resected SCLC tumors.

METHODS

Clinicopathological data and surgically resected tissue specimens from 104 SCLC patients were collected from two collaborating European institutes. Tissue sections were stained by immunohistochemistry (IHC) for all three Myc family members and the recently introduced SCLC molecular subtype-markers (ASCL1, NEUROD1, POU2F3, and YAP1).

RESULTS

IHC analysis showed C-Myc, L-Myc, and N-Myc positivity in 48%, 63%, and 9% of the specimens, respectively. N-Myc positivity significantly correlated with the POU2F3-defined molecular subtype (r = 0.6913, p = 0.0056). SCLC patients with C-Myc positive tumors exhibited significantly worse overall survival (OS) (20 vs. 44 months compared to those with C-Myc negative tumors, p = 0.0176). Ultimately, in a multivariate risk model adjusted for clinicopathological and treatment confounders, positive C-Myc expression was confirmed as an independent prognosticator of impaired OS (HR 1.811, CI 95% 1.054-3.113, p = 0.032).

CONCLUSIONS

Our study provides insights into the clinical aspects of Myc family members in surgically resected SCLC tumors. Notably, besides showing that positivity of Myc family members varies across the patients, we also reveal that C-Myc protein expression independently correlates with worse survival outcomes. Further studies are warranted to investigate the role of Myc family members as potential prognostic and predictive markers in this hard-to-treat disease.

Clinical insights into small cell lung cancer: Tumor heterogeneity, diagnosis, therapy, and future directions

Small cell lung cancer (SCLC) is characterized by rapid growth and high metastatic capacity. It has strong epidemiologic and biologic links to tobacco carcinogens. Although the majority of SCLCs exhibit neuroendocrine features, an important subset of tumors lacks these properties. Genomic profiling of SCLC reveals genetic instability, almost universal inactivation of the tumor suppressor genes TP53 and RB1, and a high mutation burden. Because of early metastasis, only a small fraction of patients are amenable to curative-intent lung resection, and these individuals require adjuvant platinum-etoposide chemotherapy. Therefore, the vast majority of patients are currently being treated with chemoradiation with or without immunotherapy. In patients with disease confined to the chest, standard therapy includes thoracic radiotherapy and concurrent platinum-etoposide chemotherapy. Patients with metastatic (extensive-stage) disease are treated with a combination of platinum-etoposide chemotherapy plus immunotherapy with an anti-programmed death-ligand 1 monoclonal antibody. Although SCLC is initially very responsive to platinum-based chemotherapy, these responses are transient because of the development of drug resistance. In recent years, the authors have witnessed an accelerating pace of biologic insights into the disease, leading to the redefinition of the SCLC classification scheme. This emerging knowledge of SCLC molecular subtypes has the potential to define unique therapeutic vulnerabilities. Synthesizing these new discoveries with the current knowledge of SCLC biology and clinical management may lead to unprecedented advances in SCLC patient care. Here, the authors present an overview of multimodal clinical approaches in SCLC, with a special focus on illuminating how recent advancements in SCLC research could accelerate clinical development.

Unfolding the secrets of small cell lung cancer progression: Novel approaches and insights through rapid autopsies

The understanding of small cell lung cancer (SCLC) biology has increased dramatically in recent years, but the processes that allow SCLC to progress rapidly remain poorly understood. Here, we advocate the integration of rapid autopsies and preclinical models into SCLC research as a comprehensive strategy with the potential to revolutionize current treatment paradigms.

Dual targeting of BCL-2 and MCL-1 in the presence of BAX breaks venetoclax resistance in human small cell lung cancer

BACKGROUND

No targeted drugs are currently available against small cell lung cancer (SCLC). BCL-2 family members are involved in apoptosis regulation and represent therapeutic targets in many malignancies.

METHODS

Expression of BCL-2 family members in 27 SCLC cell lines representing all known four SCLC molecular subtypes was assessed by qPCR, Western blot and mass spectrometry-based proteomics. BCL-2 and MCL-1 inhibition (venetoclax and S63845, respectively) was assessed by MTT assay and flow cytometry and in mice bearing human SCLC tumours. Drug interactions were calculated using the Combenefit software. Ectopic BAX overexpression was achieved by expression plasmids.

RESULTS

The highest BCL-2 expression levels were detected in ASCL1- and POU2F3-driven SCLC cells. Although sensitivity to venetoclax was reflected by BCL-2 levels, not all cell lines responded consistently despite their high BCL-2 expression. MCL-1 overexpression and low BAX levels were both characteristic for venetoclax resistance in SCLC, whereas the expression of other BCL-2 family members did not affect therapeutic efficacy. Combination of venetoclax and S63845 resulted in significant, synergistic in vitro and in vivo anti-tumour activity and apoptosis induction in double-resistant cells; however, this was seen only in a subset with detectable BAX. In non-responding cells, ectopic BAX overexpression sensitised to venetoclax and S63845 and, furthermore, induced synergistic drug interaction.

CONCLUSIONS

The current study reveals the subtype specificity of BCL-2 expression and sheds light on the mechanism of venetoclax resistance in SCLC. Additionally, we provide preclinical evidence that combined BCL-2 and MCL-1 targeting is an effective approach to overcome venetoclax resistance in high BCL-2-expressing SCLCs with intact BAX.

Consensus on technical procedures for simulation-based training in thoracic surgery: an international needs assessment

OBJECTIVE

To identify and prioritize technical procedures for simulation-based training to be integrated into the thoracic surgical curriculum.

METHODS

A three-round Delphi survey was conducted from February 2022 to June 2022 among 34 key opinion leaders in thoracic surgery from 14 countries worldwide. The first round was a brainstorming phase to identify technical procedures that a newly qualified thoracic surgeon should be able to perform. All the suggested procedures were categorized, qualitatively analyzed, and sent to the second round. The second round investigated: the frequency of the identified procedure at each institution, the number of thoracic surgeons that should be able to perform these procedures, the degree of risk to the patient if the procedure is performed by a non-competent thoracic surgeon, and the feasibility of simulation-based education. In the third round, elimination, and re-ranking of the procedures from the second round were performed.

RESULTS

Response rates in the three iterative rounds were 80% (28 out of 34), 89% (25 out of 28) and 100% (25 out of 25) in the first, second, and third round, respectively. Seventeen technical procedures were included for simulation-based training in the final prioritized list. The top five procedures were VATS lobectomy, VATS segmentectomy, VATS mediastinal lymph node dissection, diagnostic flexible bronchoscopy, and RATS port placement, RATS docking and undocking.

CONCLUSION

The prioritized list of procedures represents a consensus of key thoracic surgeons worldwide. These procedures are suitable for simulation-based training and should be integrated in the thoracic surgical curriculum.

Expression patterns and prognostic relevance of subtype-specific transcription factors in surgically resected small cell lung cancer: an international multicenter study

The tissue distribution and prognostic relevance of subtype‐specific proteins (ASCL1, NEUROD1, POU2F3, YAP1) present an evolving area of research in small‐cell lung cancer (SCLC). The expression of subtype‐specific transcription factors and P53 and RB1 proteins were measured by immunohistochemistry (IHC) in 386 surgically resected SCLC samples. Correlations between subtype‐specific proteins and in vitro efficacy of various therapeutic agents were investigated by proteomics and cell viability assays in 26 human SCLC cell lines. Besides SCLC‐A (ASCL1‐dominant), SCLC‐AN (combined ASCL1/NEUROD1), SCLC‐N (NEUROD1‐dominant), and SCLC‐P (POU2F3‐dominant), IHC and cluster analyses identified a quadruple‐negative SCLC subtype (SCLC‐QN). No unique YAP1‐subtype was found. The highest overall survival rates were associated with non‐neuroendocrine subtypes (SCLC‐P and SCLC‐QN) and the lowest with neuroendocrine subtypes (SCLC‐A, SCLC‐N, SCLC‐AN). In univariate analyses, high ASCL1 expression was associated with poor prognosis and high POU2F3 expression with good prognosis. Notably, high ASCL1 expression influenced survival outcomes independently of other variables in a multivariate model. High POU2F3 and YAP1 protein abundances correlated with sensitivity and resistance to standard‐of‐care chemotherapeutics, respectively. Specific correlation patterns were also found between the efficacy of targeted agents and subtype‐specific protein abundances. In conclusion, we investigated the clinicopathological relevance of SCLC molecular subtypes in a large cohort of surgically resected specimens. Differential IHC expression of ASCL1, NEUROD1, and POU2F3 defines SCLC subtypes. No YAP1‐subtype can be distinguished by IHC. High POU2F3 expression is associated with improved survival in a univariate analysis, whereas elevated ASCL1 expression is an independent negative prognosticator. Proteomic and cell viability assays of human SCLC cell lines revealed distinct vulnerability profiles defined by transcription regulators. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Nationwide lung cancer screening with low-dose computed tomography: implementation and first results of the HUNCHEST screening program

OBJECTIVES

Lung cancer (LC) kills more people than any other cancer in Hungary. Hence, there is a clear rationale for considering a national screening program. The HUNCHEST pilot program primarily aimed to investigate the feasibility of a population-based LC screening in Hungary, and determine the incidence and LC probability of solitary pulmonary nodules.

METHODS

A total of 1890 participants were assigned to undergo low-dose CT (LDCT) screening, with intervals of 1 year between procedures. Depending on the volume, growth, and volume doubling time (VDT), screenings were defined as negative, indeterminate, or positive. Non-calcified lung nodules with a volume > 500 mm³ and/or a VDT < 400 days were considered positive. LC diagnosis was based on histology.

RESULTS

At baseline, the percentage of negative, indeterminate, and positive tests was 81.2%, 15.1%, and 3.7%, respectively. The frequency of positive and indeterminate LDCT results was significantly higher in current smokers (vs. non-smokers or former smokers; p < 0.0001) and in individuals with COPD (vs. those without COPD, p < 0.001). In the first screening round, 1.2% (n = 23) of the participants had a malignant lesion, whereas altogether 1.5% (n = 29) of the individuals were diagnosed with LC. The overall positive predictive value of the positive tests was 31.6%. Most lung malignancies were diagnosed at an early stage (86.2% of all cases).

CONCLUSIONS

In terms of key characteristics, our prospective cohort study appears consistent to that of comparable studies. Altogether, the results of the HUNCHEST pilot program suggest that LDCT screening may facilitate early diagnosis and thus curative-intent treatment in LC.

KEY POINTS

• The HUNCHEST pilot study is the first nationwide low-dose CT screening program in Hungary. • In the first screening round, 1.2% of the participants had a malignant lesion, whereas altogether 1.5% of the individuals were diagnosed with lung cancer. • The overall positive predictive value of the positive tests in the HUNCHEST screening program was 31.6%.

Bone-Specific Metastasis Pattern of Advanced-Stage Lung Adenocarcinoma According to the Localization of the Primary Tumor

Background: Patients with advanced-stage lung adenocarcinoma (LADC) often develop distant metastases in the skeletal system. Yet, the bone-specific metastasis pattern is still controversial. We, therefore, aimed to examine how the primary tumor location affects bone specificity and survival in LADC patients diagnosed with skeletal metastases. Methods: In total, 209 bone-metastatic Caucasian LADC patients from two thoracic centers were included in this study. Focusing on the specific location of primary tumors and bone metastatic sites, clinicopathological variables were included in a common database and analyzed retrospectively. Skeletal metastases were diagnosed according to the contemporary diagnostic guidelines and confirmed by bone scintigraphy. Besides region- and side-specific localization, primary tumors were also classified as central or peripheral tumors based on their bronchoscopic visibility. Results: The most common sites for metastasis were the spine (n = 103) and the ribs (n = 60), followed by the pelvis (n = 36) and the femur (n = 22). Importantly, femoral (p = 0.022) and rib (p = 0.012) metastases were more frequently associated with peripheral tumors, whereas centrally located LADCs were associated with humeral metastases (p = 0.018). Moreover, we deduced that left-sided tumors give rise to skull metastases more often than right-sided primary tumors (p = 0.018). Of note, however, the localization of the primary tumor did not significantly influence the type of affected bones. Multivariate Cox regression analysis adjusted for clinical parameters demonstrated that central localization of the primary tumor was an independent negative prognostic factor for overall survival (OS). Additionally, as expected, both chemotherapy and bisphosphonate therapy conferred a significant benefit for OS. Conclusion: The present study demonstrates unique bone-specific metastasis patterns concerning primary tumor location. Peripherally located LADCs are associated with rib and femoral metastases and improved survival outcomes. Our findings might contribute to the development of individualized follow-up strategies in bone-metastatic LADC patients and warrant further clinical investigations on a larger sample size.

Clinical relevance of circulating activin A and follistatin in small cell lung cancer

OBJECTIVES

Circulating levels of activin A (ActA) and follistatin (FST) have been investigated in various disorders including malignancies. However, to date, their diagnostic and prognostic relevance is largely unknown in small cell lung cancer (SCLC). Our aim was to evaluate circulating ActA and FST levels as potential biomarkers in this devastating disease.

METHODS

Seventy-nine Caucasian SCLC patients and 67 age- and sex-matched healthy volunteers were included in this study. Circulating ActA and FST concentrations were measured by ELISA and correlated with clinicopathological parameters and long-term outcomes.

RESULTS

Plasma ActA and FST concentrations were significantly elevated in SCLC patients when compared to healthy volunteers (p < 0.0001). Furthermore, extensive-stage SCLC patients had significantly higher circulating ActA levels than those with limited-stage disease (p = 0.0179). Circulating FST concentration was not associated with disease stage (p = 0.6859). Notably, patients with high (≥548.8 pg/ml) plasma ActA concentration exhibited significantly worse median overall survival (OS) compared to those with low (<548.8 pg/ml) ActA levels (p = 0.0009). Moreover, Cox regression analysis adjusted for clinicopathological parameters revealed that high ActA concentration is an independent predictor of shorter OS (HR: 1.932; p = 0.023). No significant differences in OS have been observed with regards to plasma FST levels (p = 0.1218).

CONCLUSION

Blood ActA levels are elevated and correlate with disease stage in SCLC patients. Measurement of circulating ActA levels might help in the estimation of prognosis in patients with SCLC.

Prognostic impact of PD-1 and PD-L1 expression in malignant pleural mesothelioma: an international multicenter study

BACKGROUND

Programmed cell death 1/programmed death ligand 1 (PD-1/PD-L1) immune-checkpoint blockade is a promising new therapeutic strategy in cancer. However, expression patterns and prognostic significance of PD-L1 and PD-1 are still controversial in human malignant pleural mesothelioma (MPM).

METHODS

Formalin-fixed paraffin-embedded (FFPE) tumor samples from 203 MPM patients receiving standard treatment without immunotherapy were collected from 5 European centers. PD-L1 and PD-1 expression of tumor cells (TCs) and tumor-infiltrating lymphocytes (TILs) were measured by immunohistochemistry and correlated with clinical parameters and long-term outcome.

RESULTS

High (>10%) PD-L1 TC and PD-1 TILs expressions were found in 18 (8%) and 39 (24%) patients, respectively. PD-L1 was rarely expressed by TILs [≥1%, n=13 (8%); >10%, n=1]. No significant associations were found between the PD-L1 or PD-1 expression of TCs or TILs and clinicopathological parameters such as stage or histological subtype. Notably, patients with high (>10%) TC-specific PD-L1 expression exhibited significantly worse median overall survival (OS) (6.3 vs. 15.1 months of those with low TC PD-L1 expression; HR: 2.51, P<0.001). In multivariate cox regression analysis adjusted for clinical parameters, high TC PD-L1 expression (>10%) proved to be an independent negative prognostic factor for OS (HR: 2.486, P=0.005). There was no significant correlation between PD-L1 or PD-1 expression of TILs and OS.

CONCLUSIONS

In this multicenter cohort study, we demonstrate that high (>10%) PD-L1 expression of TCs independently predicts worse OS in MPM. Further studies are warranted to investigate the value of PD-L1/PD-1 expression as a marker for treatment response in MPM patients receiving immunotherapy.

Molecular profiles of small cell lung cancer subtypes: therapeutic implications

Small cell lung cancer (SCLC; accounting for approximately 13%-15% of all lung cancers) is an exceptionally lethal malignancy characterized by rapid doubling time and high propensity to metastasize. In contrast to the increasingly personalized therapies in other types of lung cancer, SCLC is still regarded as a homogeneous disease and the prognosis of SCLC patients remains poor. Recently, however, substantial progress has been made in our understanding of SCLC biology. Advances in genomics and development of new preclinical models have facilitated insights into the intratumoral heterogeneity and specific genetic alterations of this disease. This worldwide resurgence of studies on SCLC has ultimately led to the development of novel subtype-specific classifications primarily based on the neuroendocrine features and distinct molecular profiles of SCLC. Importantly, these biologically distinct subtypes might define unique therapeutic vulnerabilities. Herein, we summarize the current knowledge on the molecular profiles of SCLC subtypes with a focus on their potential clinical implications.

The effectiveness of pulmonary rehabilitation in connection with lung transplantation in Hungary

BACKGROUND

The role of pre- and post-lung transplant rehabilitation is to maintain or improve exercise tolerance, lung mechanics, peripheral and respiratory muscle function. Our aim was to measure the effectiveness of pre- and post-transplant rehabilitation in terms of the changes of functional and quality of life markers.

METHODS

Sixty-three patients (40 COPD FEV1: 21±5%pred, 18 IPF TLC: 42±13%pred, 4 bronchiectasis FEV1: 28±4%pred and 1 alveolitis fibrotisans TLC: 31%pred) participated in a pre- and 14 took part in a post-transplant rehabilitation program (more than 2 months after lung transplantation (LTx), primary diagnoses: 9 COPD, 4 IPF). The rehabilitation program consisted of chest-wall stretching, controlled breathing techniques and personalized exercise of 20-30 minutes by cycling and treadmill 2-3 times per day for 4 weeks. Seven functional and quality of life markers, like lung function, chest wall expansion (CWE), 6-minute walking distance (6MWD), modified Medical Research Council Dyspnea Scale (mMRC), COPD Assessment Test (CAT), breath holding time (BHT) and hand grip strength (HGS) were measured at the onset and the end of the rehabilitation program. The safety profile of the rehabilitation program was followed-up.

RESULTS

Pre-transplant pulmonary rehabilitation resulted in significant improvement in CWE (3.24±1.49 vs. 4.48±1.62 cm), CAT IQR {19 [13-25] vs. 15 [11-21]}, 6MWD (315±118 vs. 375±114 m), P<0.05. FEV1, FVC, mMRC, BHT and HGS did not change significantly. Post-transplant rehabilitation resulted in significant improvement in CWE (3.7±2.1 vs. 6.2±1.8 cm), CAT IQR {17 [11-23] vs. 10 [6-14], BHT (22±14 vs. 35±16 s), FEV1 (73±8 vs. 86±9%pred) and FVC (70±12 vs. 85±14%pred), P<0.05. The 6MWD, mMRC and HGS did not change significantly. No cardiovascular or other side effects were detected during the rehabilitation program.

CONCLUSIONS

Our results underline the importance of perioperative pulmonary rehabilitation in the complex treatment of lung transplant patients in Hungary, as well. There was a limitation because no control group was evaluated without rehabilitation.

The landscape of small cell lung cancer metastases: Organ specificity and timing

BACKGROUND

Early metastasis is a hallmark of small cell lung cancer (SCLC). However, the mechanisms and resulting patterns of SCLC dissemination are unclear. Our aim was thus to investigate the organ specificity and timing of blood-borne metastases in a comprehensive large cohort of SCLC patients.

METHODS

In this retrospective non-interventional cross-sectional study of 1009 Caucasian SCLC patients, we investigated the correlation between the distinct locations of the primary tumor and metastatic sites.

RESULTS

The onset of bone (p < 0.001), brain (p < 0.001), and pericardial (p = 0.02) metastases were late events, whereas adrenal gland (p = 0.005) and liver (p < 0.001) metastases occurred earlier. No significant difference was found in the distribution of early versus late metastases when comparing central and peripheral primary tumors. Patients with bone metastases had a higher than expected likelihood of having liver metastases, while brain metastases tended to appear together with adrenal gland metastases. Pleural and both lung and pericardial metastases also tended to co-metastasize together more frequently than expected if metastatic events occurred independently. Notably, patients with central primary tumors had decreased median overall survival (OS) compared to those with peripheral tumors, although this tendency does not appear to be significant (p = 0.072).

CONCLUSION

Our results are suggestive for particular site- and sequence-specific metastasis patterns in human SCLC. SCLC bone metastases tend to appear together with liver metastases, while brain metastases occur together with adrenal gland metastases. Better understanding of metastasis distribution patterns might help to improve the diagnosis and therapeutic decision-making in SCLC patients.

EGFR variant allele frequency predicts EGFR-TKI efficacy in lung adenocarcinoma: a multicenter study

Background

Although lung adenocarcinoma (LADC) with sensitizing mutations of the epidermal growth factor receptor (EGFR) is highly sensitive to EGFR tyrosine kinase inhibitors (EGFR-TKIs), in most cases disease progression inevitably occurs. Our aim was to investigate the predictive and prognostic significance of adjusted tumoral EGFR variant allele frequency (EGFR-aVAF) in the above setting.

Methods

Eighty-nine Caucasian advanced-stage LADC patients with known exon-specific EGFR mutations undergoing EGFR-TKI treatment were included. The correlations of EGFR-aVAF with clinicopathological variables including progression-free and overall survival (PFS and OS, respectively) were retrospectively analyzed.

Results

Of 89 EGFR-mutant LADC patients, 46 (51.7%) had exon 19 deletion, while 41 (46.1%) and 2 (2.2%) patients had exon 21- and exon 18-point mutations, respectively. Tumoral EGFR-aVAF was significantly higher in patients harboring EGFR exon 19 mutations than in those with exon 21-mutant tumors (P<0.001). Notably, patients with EGFR exon 19 mutant tumors demonstrated significantly improved PFS (P=0.003) and OS (P=0.02) compared to patients with exon 21 mutations. Irrespective of specific exon mutations, a statistically significant positive linear correlation was found between EGFR-aVAF of tumoral tissue and PFS (r=0.319; P=0.002). High (≥70%) EGFR-aVAF was an independent predictor of longer PFS [vs. low (<70%) EGFR-aVAF; median PFSs were 52 vs. 26 weeks, respectively; P<0.001]. Additionally, patients with high EGFR-aVAF also had significantly improved OS than those with low EGFR-aVAF (P=0.011).

Conclusions

Our study suggests that high (≥70%) EGFR-aVAF of tumoral tissue predicts benefit from EGFR-TKI treatment in advanced LADC and, moreover, that exon 19 EGFR mutation is associated with high EGFR-aVAF and improved survival outcomes.

The effects of bisphosphonate and radiation therapy in bone-metastatic lung adenocarcinoma: the impact of KRAS mutation

Background

KRAS mutation is the most common genetic alteration in lung adenocarcinoma (LADC) in Western countries and is associated with worse outcome in bone-metastatic cases. Yet, to date, no effective treatment guidelines were developed for these patients. Accordingly, our aim was to investigate the impact of KRAS mutation on bisphosphonate (BTx) and radiation therapy (RTx) in bone-metastatic LADC patients.

Methods

Clinicopathological variables of 134 consecutive LADC patients with bone metastases at diagnosis and known KRAS status were retrospectively analyzed. The effects of BTx, RTx and KRAS mutation on overall survival (OS) were investigated.

Results

Of the total cohort, 93 patients were identified as KRAS wild-type (WT) (69.4%) and 41 (30.6%) as KRAS mutant patients. The presence of KRAS mutation was associated with significantly reduced median OS (5.1 vs. 10.2 months in KRAS WT patients; P=0.008). Irrespective of KRAS mutational status both BTx (P=0.007) and RTx (P=0.021) conferred a significant benefit for OS. Notably, however, when analyzing the patients with KRAS-mutant and KRAS WT tumors separately, the benefit from BTx and RTx on OS remained statistically significant only in KRAS WT patients (P=0.032 and P=0.031, respectively).

Conclusions

KRAS mutation is a strong negative prognostic factor in bone-metastatic LADC patients. Both BTx and RTx can increase the OS with a pronounced benefit for patients with KRAS WT tumors. Altogether, KRAS mutational status should be considered during therapeutic decision making in bone-metastatic LADC patients.

KRAS Mutations Predict Response and Outcome in Advanced Lung Adenocarcinoma Patients Receiving First-Line Bevacizumab and Platinum-Based Chemotherapy

Bevacizumab, combined with platinum-based chemotherapy, has been widely used in the treatment of advanced-stage lung adenocarcinoma (LADC). Although KRAS (V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog) mutation is the most common genetic alteration in human LADC and its role in promoting angiogenesis has been well established, its prognostic and predictive role in the above setting remains unclear. The association between KRAS exon 2 mutational status and clinicopathological variables including progression-free survival and overall survival (PFS and OS, respectively) was retrospectively analyzed in 501 Caucasian stage IIIB-IV LADC patients receiving first-line platinum-based chemotherapy (CHT) with or without bevacizumab (BEV). EGFR (epidermal growth factor receptor)-mutant cases were excluded. Of 247 BEV/CHT and 254 CHT patients, 95 (38.5%) and 75 (29.5%) had mutations in KRAS, respectively. KRAS mutation was associated with smoking (p = 0.008) and female gender (p = 0.002) in the BEV/CHT group. We found no difference in OS between patients with KRAS-mutant versus KRAS wild-type tumors in the CHT-alone group (p = 0.6771). Notably, patients with KRAS-mutant tumors demonstrated significantly shorter PFS (p = 0.0255) and OS (p = 0.0186) in response to BEV/CHT compared to KRAS wild-type patients. KRAS mutation was an independent predictor of shorter PFS (hazard ratio, 0.597; p = 0.011) and OS (hazard ratio, 0.645; p = 0.012) in the BEV/CHT group. G12D KRAS-mutant patients receiving BEV/CHT showed significantly shorter PFS (3.7 months versus 8.27 months in the G12/13x group; p = 0.0032) and OS (7.2 months versus 16.1 months in the G12/13x group; p = 0.0144). In this single-center, retrospective study, KRAS-mutant LADC patients receiving BEV/CHT treatment exhibited inferior PFS and OS compared to those with KRAS wild-type advanced LADC. G12D mutations may define a subset of KRAS-mutant LADC patients unsuitable for antiangiogenic therapy with BEV.

High circulating activin A level is associated with tumor progression and predicts poor prognosis in lung adenocarcinoma

Activin A (ActA)/follistatin (FST) signaling has been shown to be deregulated in different tumor types including lung adenocarcinoma (LADC). Here, we report that serum ActA protein levels are significantly elevated in LADC patients (n=64) as compared to controls (n=46, p=0.015). ActA levels also correlated with more advanced disease stage (p<0.0001) and T (p=0.0035) and N (p=0.0002) factors. M1 patients had significantly higher ActA levels than M0 patients (p<0.001). High serum ActA level was associated with poor overall survival (p<0.0001) and was confirmed as an independent prognostic factor (p=0.004). Serum FST levels were increased only in female LADC patients (vs. female controls, p=0.031). Two out of five LADC cell lines secreted biologically active ActA, while FST was produced in all of them. Transcripts of both type I and II ActA receptors were detected in all five LADC cell lines. In conclusion, our study does not only suggest that measuring blood ActA levels in LADC patients might improve the prediction of prognosis, but also indicates that this parameter might be a novel non-invasive biomarker for identifying LADC patients with organ metastases.

Circulating complement component 4d (C4d) correlates with tumor volume, chemotherapeutic response and survival in patients with malignant pleural mesothelioma

Only limited information is available on the role of complement activation in malignant pleural mesothelioma (MPM). Thus, we investigated the circulating and tissue levels of the complement component 4d (C4d) in MPM. Plasma samples from 55 MPM patients, 21 healthy volunteers (HV) and 14 patients with non-malignant pleural diseases (NMPD) were measured by ELISA for C4d levels. Tissue specimens from 32 patients were analyzed by C4d immunohistochemistry. Tumor volumetry was measured in 20 patients. We found no C4d labeling on tumor cells, but on ectopic lymphoid structures within the tumor stroma. Plasma C4d levels did not significantly differ between MPM, HV or NMPD. Late-stage MPM patients had higher plasma C4d levels compared to early-stage (p = 0.079). High circulating C4d was associated with a higher tumor volume (p = 0.047). Plasma C4d levels following induction chemotherapy were significantly higher in patients with stable/progressive disease compared to those with partial/major response (p = 0.005). Strikingly, patients with low C4d levels at diagnosis had a significantly better overall survival, confirmed in a multivariate cox regression model (hazard ratio 0.263, p = 0.01). Our findings suggest that circulating plasma C4d is a promising new prognostic biomarker in patients with MPM and, moreover, helps to select patients for surgery following induction chemotherapy.

The evidence for and against different modes of tumour cell extravasation in the lung: diapedesis, capillary destruction, necroptosis, and endothelialization

The development of lung metastasis is a significant negative prognostic factor for cancer patients. The extravasation phase of lung metastasis involves interactions of tumour cells with the pulmonary endothelium. These interactions may have broad biological and medical significance, with potential clinical implications ranging from the discovery of lung metastasis biomarkers to the identification of targets for intervention in preventing lung metastases. Because of the potential significance, the mechanisms of tumour cell extravasation require cautious, systematic studies. Here, we discuss the literature pertaining to the proposed mechanisms of extravasation and critically compare a recently proposed mechanism (tumour cell-induced endothelial necroptosis) with the already described extravasation mechanisms in the lung. We also provide novel data that may help to explain the underlying physiological basis for endothelialization as a mechanism of tumour cell extravasation in the lung. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

KRAS-mutation incidence and prognostic value are metastatic site-specific in lung adenocarcinoma: poor prognosis in patients with KRAS mutation and bone metastasis

Current guidelines lack comprehensive information on the metastatic site-specific role of KRAS mutation in lung adenocarcinoma (LADC). We investigated the effect of KRAS mutation on overall survival (OS) in this setting. In our retrospective study, 500 consecutive Caucasian metastatic LADC patients with known KRAS mutational status were analyzed after excluding 32 patients with EGFR mutations. KRAS mutation incidence was 28.6%. The most frequent metastatic sites were lung (45.6%), bone (26.2%), adrenal gland (17.4%), brain (16.8%), pleura (15.6%) and liver (11%). Patients with intrapulmonary metastasis had significantly increased KRAS mutation frequency compared to those with extrapulmonary metastases (35% vs 26.5%, p = 0.0125). In contrast, pleural dissemination and liver involvement were associated with significantly decreased KRAS mutation incidence (vs all other metastatic sites; 17% (p < 0.001) and 16% (p = 0.02) vs 33%, respectively). Strikingly, we found a significant prognostic effect of KRAS status only in the bone metastatic subcohort (KRAS-wild-type vs KRAS-mutant; median OS 9.7 v 3.7 months; HR, 0.49; 95% CI, 0.31 to 0.79; p  = 0.003). Our study suggests that KRAS mutation frequency in LADC patients shows a metastatic site dependent variation and, moreover, that the presence of KRAS mutation is associated with significantly worse outcome in bone metastatic cases.

Vessel co-option is common in human lung metastases and mediates resistance to anti-angiogenic therapy in preclinical lung metastasis models

Anti‐angiogenic therapies have shown limited efficacy in the clinical management of metastatic disease, including lung metastases. Moreover, the mechanisms via which tumours resist anti‐angiogenic therapies are poorly understood. Importantly, rather than utilizing angiogenesis, some metastases may instead incorporate pre‐existing vessels from surrounding tissue (vessel co‐option). As anti‐angiogenic therapies were designed to target only new blood vessel growth, vessel co‐option has been proposed as a mechanism that could drive resistance to anti‐angiogenic therapy. However, vessel co‐option has not been extensively studied in lung metastases, and its potential to mediate resistance to anti‐angiogenic therapy in lung metastases is not established. Here, we examined the mechanism of tumour vascularization in 164 human lung metastasis specimens (composed of breast, colorectal and renal cancer lung metastasis cases). We identified four distinct histopathological growth patterns (HGPs) of lung metastasis (alveolar, interstitial, perivascular cuffing, and pushing), each of which vascularized via a different mechanism. In the alveolar HGP, cancer cells invaded the alveolar air spaces, facilitating the co‐option of alveolar capillaries. In the interstitial HGP, cancer cells invaded the alveolar walls to co‐opt alveolar capillaries. In the perivascular cuffing HGP, cancer cells grew by co‐opting larger vessels of the lung. Only in the pushing HGP did the tumours vascularize by angiogenesis. Importantly, vessel co‐option occurred with high frequency, being present in >80% of the cases examined. Moreover, we provide evidence that vessel co‐option mediates resistance to the anti‐angiogenic drug sunitinib in preclinical lung metastasis models. Assuming that our interpretation of the data is correct, we conclude that vessel co‐option in lung metastases occurs through at least three distinct mechanisms, that vessel co‐option occurs frequently in lung metastases, and that vessel co‐option could mediate resistance to anti‐angiogenic therapy in lung metastases. Novel therapies designed to target both angiogenesis and vessel co‐option are therefore warranted. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Mechanisms of vascularization in murine models of primary and metastatic tumor growth

Directed capillary ingrowth has long been considered synonymous with tumor vascularization. However, the vasculature of primary tumors and metastases is not necessarily formed by endothelial cell sprouting; instead, malignant tumors can acquire blood vessels via alternative vascularization mechanisms, such as intussusceptive microvascular growth, vessel co-option, and glomeruloid angiogenesis. Importantly, in response to anti-angiogenic therapies, malignant tumors can switch from one vascularization mechanism to another. In this article, we briefly review the biological features of these mechanisms and discuss on their significance in medical oncology.

Apelin promotes lymphangiogenesis and lymph node metastasis

Whereas the role of the G-protein-coupled APJ receptor and its ligand, apelin, in angiogenesis has been well documented, the ability of the apelin/APJ system to induce lymphangiogenesis and lymphatic metastasis has been largely unexplored. To this end, we first show that APJ is expressed in lymphatic endothelial cells (LECs) and, moreover, that it responds to apelin by activating the apelinergic signaling cascade. We find that although apelin treatment does not influence the proliferation of LECs in vitro, it enhances their migration, protects them against UV irradiation-induced apoptosis, increases their spheroid numbers in 3D culture, stimulates their in vitro capillary-like tube formation and, furthermore, promotes the invasive growth of lymphatic microvessels in vivo in the matrigel plug assay. We also demonstrate that apelin overexpression in malignant cells is associated with accelerated in vivo tumor growth and with increased intratumoral lymphangiogenesis and lymph node metastasis. These results indicate that apelin induces lymphangiogenesis and, accordingly, plays an important role in lymphatic tumor progression. Our study does not only reveal apelin as a novel lymphangiogenic factor but might also open the door for the development of novel anticancer therapies targeting lymphangiogenesis.

Discrimination of clinical stages in non-small cell lung cancer patients by serum HSP27 and HSP70: a multi-institutional case-control study

INTRODUCTION

Lung cancer represents a major healthcare problem. Accordingly, there is an urgent need to identify serum biomarkers for early diagnosis of lung pathology. We have recently described that patients with manifest COPD evidence elevated levels of heat shock proteins (HSPs). Based on these data, we speculated whether HSPs are also increased in patients with diagnosed lung cancer.

METHODS

Serum levels of HSP27, phospho-HSP27 (pHSP27) and HSP70 in patients with non-small cell lung cancer (NSCLC) diagnosed at an early (stages I-II, n=37) or advanced (stages IIIA-IV, n=72) stage were determined by using ELISA. Healthy smokers (n=24), healthy never-smoker volunteers (n=33) and COPD patients (n=34) according to GOLD classification served as control population.

RESULTS

Serum levels of HSP27 were elevated in patients with NSCLC diagnosed at an early or advanced stage when compared with both healthy control groups (P<0.005 and P<0.0001 respectively). Statistically significant differences were furthermore found between the groups of patients with early vs. advanced stage NSCLC (P=0.0021). Serum levels of HSP70 were also significantly elevated in patients with NSCLC diagnosed at an early or at an advanced stage when compared with either healthy control groups (P=0.0028 and P<0.0001 respectively). In univariate logistic regression models including healthy subjects and patients with NSCLC, HSP70 had an area under the curve (AUC) of 0.779 (P<0.0001) and HSP27 showed an AUC of 0.870 (P<0.0001).

CONCLUSION

Our data suggest that serum HSP27 levels might serve as a possible tool to discriminate between early and advanced stages NSCLC.

Airway pathogens during the first year after lung transplantation: a single-center experience

After lung transplantation, a high level of immunosuppression is needed to prevent rejection. This demand renders recipients more sensitive to infections. As pulmonary infections are a major clinical problem during the first postoperative year after lung transplantation, preventive treatment and regular surveillance examinations are needed for immediate, adequate therapy. We describe the airway pathogens registered during the first posttransplantation year among our 12 lung transplant recipients since December 2008. Samples were obtained for microbiologic analysis from the upper and lower respiratory tracts and from serum as part of routine care. During the first year after transplantation the most frequent pathogens were fungi (Candida albicans 82%; Aspergillus 50%), Pneumocystis (8%), gram-negative bacteria (Pseudomonas spp 60%; Klebsiella 25%, Acinetobacter 17%; Escherichia Coli 17%; and Enterococcus faecalis 25%), and Staphylococcus aureus (50%, including methicillin-resistant strains 25%). This pathogen spectrum in the first postoperative year after lung transplantation was similar to other centers. Colonization with Pseudomonas or fungi presented early and was prevalent among our patients.

High VEGFR-3-positive circulating lymphatic/vascular endothelial progenitor cell level is associated with poor prognosis in human small cell lung cancer

PURPOSE

The newly identified bone marrow-derived cell population, called lymphatic/vascular endothelial progenitor cells (LVEPC), has been shown to contribute to lymph capillary growth in experimental tumor systems. The clinical significance of these cells has not yet been investigated in a human malignancy. Our aim was to study whether peripheral blood circulating LVEPCs participate in the progression of human small cell lung cancer (SCLC).

EXPERIMENTAL DESIGN

A total of 88 patients with limited-stage SCLC and 32 tumor-free control subjects were included. Peripheral blood circulating LVEPC labeled with CD34 and vascular endothelial growth factor receptor-3 (VEGFR3) antibodies and the serum levels of the key lymphangiogenic molecule VEGF-C were measured by flow cytometry and ELISA, respectively.

RESULTS

CD34-positive/VEGFR3-positive LVEPC levels were significantly increased in patients (versus controls; P<0.01), and there was also a significant relationship between LVEPC counts and lymph node metastasis (P<0.01). High pretreatment circulating LVEPC numbers correlated with poor overall survival (P<0.01). Although we observed significantly elevated VEGF-C concentrations in patients (versus controls; P<0.01), there was no significant correlation between VEGF-C and LVEPC levels. Moreover, no significant differences in peripheral blood VEGF-C levels were seen between patients subgrouped by clinicopathologic variables including tumor and lymph node stages and survival.

CONCLUSIONS

Peripheral blood levels of bone marrow-derived LVEPCs are significantly increased in patients with SCLC and correlate with lymphatic involvement and prognosis. This is the first study that shows evidence of increased numbers of circulating LVEPC in patients with a malignant tumor.

Role of retinoic receptors in lung carcinogenesis

Several in vitro and in vivo studies have examined the positive and negative effects of retinoids (vitamin A analogs) in premalignant and malignant lesions. Retinoids have been used as chemopreventive and anticancer agents because of their pleiotropic regulator function in cell differentiation, growth, proliferation and apoptosis through interaction with two types of nuclear receptors: retinoic acid receptors and retinoid X receptors. Recent investigations have gradually elucidated the function of retinoids and their signaling pathways and may explain the failure of earlier chemopreventive studies.

In this review we have compiled basic and recent knowledge regarding the role of retinoid receptors in lung carcinogenesis. Sensitive and appropriate biological tools are necessary for screening the risk population and monitoring the efficacy of chemoprevention. Investigation of retinoid receptors is important and may contribute to the establishment of new strategies in chemoprevention for high-risk patients and in the treatment of lung cancer.

Lymphangiogenesis correlates with lymph node metastasis, prognosis, and angiogenic phenotype in human non-small cell lung cancer

PURPOSE

Recent experimental studies have revealed that lymphangiogenesis plays an important role in cancer progression, but its clinical significance in the case of non-small cell lung cancer (NSCLC) remains unclear. Our aim was to assess the lymphangiogenesis of human NSCLC, and to correlate this with angiogenic phenotype (angiogenic versus nonangiogenic growth pattern) and clinical behavior.

EXPERIMENTAL DESIGN

One hundred and three patients with NSCLC and complete follow-up information were included. Tumor samples were immunostained for vascular endothelial growth factor-C (VEGF-C), the lymphatic endothelial markers, LYVE-1 and D2-40/Podoplanin, and the panvascular marker, CD31. Lymphatic vessel density (LVD) and perimeters were evaluated within the tumor and peritumorally.

RESULTS

LVDs at the tumor periphery were significantly higher in lymph node metastatic tumors (P < 0.005) and high LVDs correlated with poor overall survival (P < 0.001). However, this tendency proved to be significant only in the angiogenic tumor group (P < 0.001). Although 68% of the patients with nonangiogenic tumors had lymph node metastasis (P = 0.0048 versus angiogenic tumors), in the patient group with nonangiogenic NSCLCs, there was no information from the LVDs in any investigated tumor area (P > 0.05). In contrast to angiogenic tumors, which had actively sprouting lymphatics in all of the investigated tumor areas, nonangiogenic tumors showed no Ki67 staining intratumorally.

CONCLUSIONS

Our results reveal tumor lymphangiogenesis as a novel prognostic indicator for the risk of lymph node metastasis in NSCLC. Moreover, it also provides the first evidence that nonangiogenic NSCLCs mainly co-opt host tissue lymphatics during their growth, in contrast to most of the angiogenic tumors, which expand with concomitant lymphangiogenesis.

The association of carotid artery stenosis with carotid sinus hypersensitivity. Transitory cerebral ischaemic attack provoked by carotid sinus reflex

The association of internal carotid stenosis with the carotid sinus syndrome represents a special clinical entity. Transitory cerebral ischaemic attack (TIA) will usually be manifested by activation of carotid sinus reflex. Eighteen patients were observed suffering from both carotid sinus hypersensitivity and TIA. The patients had had TIA's for many years. Unilateral internal carotid stenosis was detected in 15 cases, while 3 patients had bilateral carotid stenosis. On carotid sinus stimulation, syncope appeared and a TIA could be provoked. The mean duration of the syncopic attack was 5500 ms and was based on sinus arrest in 14 cases and on third degree AV block in 4 cases. In all patients carotid artery disobliteration was performed; in 14 patients pacemaker implantation was necessary, while 4 patients could be treated by atropine medication. The development of a TIA could be abolished in every patient and 14 patients remained totally symptom free.