Impact of Locoregional Therapies for Brain Lesions on Survival in Patients With Non-small Cell Lung Cancer With Multiple Extrathoracic Metastases

BACKGROUND/AIM

The treatment of brain metastases in patients with non-small cell lung cancer (NSCLC) typically involves surgery, irradiation, and chemotherapy (single or combination therapy). However, the impact of these therapies on the survival of patients with NSCLC with multiple extrathoracic metastases has not yet been determined. Therefore, in the present study, we examined the prognostic effect of multimodal treatment for brain metastases in patients with NSCLC with multiple extrathoracic metastases in the absence of driver mutations.

PATIENTS AND METHODS

Patients with NSCLC with multiple extrathoracic metastases (including at least one brain metastasis), who visited Saitama Medical Center, Saitama Medical University from January 1, 2010 to December 31, 2016, were enrolled in this study; follow-up was conducted until December 31, 2021.

RESULTS

A total of 56 patients were enrolled, including 12 and 44 patients with single and multiple brain metastases, respectively. The median overall survival (OS) for all patients was 4.9 months, and did not differ significantly between patients with single and multiple brain metastases (3.0 vs. 4.9 months, respectively). The selection of locoregional treatment for brain metastases did not depend on Karnofsky performance status (p=0.0862). Among patients with multiple brain metastases, the OS for those who underwent craniotomy followed by whole brain radiation therapy (WBRT), those who received only WBRT, and those treated without locoregional therapy was 47.7, 3.9, and 15.9 months, respectively (p=0.00382).

CONCLUSION

Surgical resection followed by radiation therapy is an effective treatment option for brain metastases in patients with multiple metastases. However, WBRT alone did not improve prognosis.

Nintedanib induces gene expression changes in the lung of induced-rheumatoid arthritis–associated interstitial lung disease mice

Nintedanib is a multi-tyrosine kinase inhibitor widely used to treat progressive fibrosing interstitial lung diseases because it slows the reduction in forced vital capacity. However, the prognosis for patients treated with nintedanib remains poor. To improve nintedanib treatment, we examined the effects of nintedanib on gene expression in the lungs of induced-rheumatoid arthritis–associated interstitial lung disease model mice, which develop rheumatoid arthritis and subsequent pulmonary fibrosis. Using next-generation sequencing, we identified 27 upregulated and 130 downregulated genes in the lungs of these mice after treatment with nintedanib. The differentially expressed genes included mucin 5B and heat shock protein 70 family genes, which are related to interstitial lung diseases, as well as genes associated with extracellular components, particularly the myocardial architecture, suggesting unanticipated effects of nintedanib. Of the genes upregulated in the nintedanib-treated lung, expression of regulatory factor X2, which is suspected to be involved in cilia movement, and bone morphogenetic protein receptor type 2, which is involved in the pathology of pulmonary hypertension, was detected by immunohistochemistry and RNA in situ hybridization in peripheral airway epithelium and alveolar cells. Thus, the present findings indicate a set of genes whose expression alteration potentially underlies the effects of nintedanib on pulmonary fibrosis. It is expected that these findings will contribute to the development of improved nintedanib strategies for the treatment of progressive fibrosing interstitial lung diseases.

Initial rapidity of tumor growth as a prognostic factor for the therapeutic effect of immune-checkpoint inhibitors in patients with non-small cell lung cancer: evaluation for linear and non-linear correlation

Background

Immune-checkpoint inhibitors (ICIs) have been increasingly used for non-small cell lung cancer (NSCLC) treatment in recent years. Although insufficient, the rate of programmed death-ligand 1 expression has been adopted as a predictor of ICI efficacy. We evaluated tumor growth rate as a clinically easy-to-use predictor of the therapeutic effect of ICIs.

Methods

This study is a single-institution retrospective study in Japan. NSCLC patients treated with nivolumab, pembrolizumab, or atezolizumab at Saitama Medical Center from January 1, 2016 to December 31, 2018 were enrolled, and followed until December 31, 2020. We defined and calculated the initial rapidity of tumor progression (IRP) as: the increase in the sum of the diameters of intrathoracic tumors and lymph nodes on two series of chest computed tomography (CT) scans (one obtained at an initial checkup and the other obtained immediately before the first treatment) divided by the number of days between these CT scans. Two coefficients were calculated: the maximal information coefficient (MIC) between IRP and time to treatment failure (TTF) using the Python package with minepy library, and the Spearman's rank correlation coefficient.

Results

A total of 55 patients (median age, 70 years; 47 men) were enrolled. The median TTF with ICIs was 126 days, and four patients continued to receive ICI treatment at the end of the follow-up. The MIC between IRP and TTF was 0.302 with weak correlation, and the Spearman's rank correlation coefficient was -0.347 (P=0.00938).

Conclusions

The initial tumor growth rate had a negative linear correlation with the therapeutic effect of ICIs.

A novel isoform of Homeodomain-interacting protein kinase-2 promotes YAP/TEAD transcriptional activity in NSCLC cells

Homeodomain-interacting protein kinase-2 (HIPK2) can either promote or inhibit transcription depending on cellular context. In this study, we show that a new HIPK2 isoform increases TEAD reporter activity in NSCLC cells. We detected HIPK2 copy number gain in 5/6 (83.3%) NSCLC cell lines. In NSCLC patients with high HIPK2 mRNA expression in the Human Protein Atlas, the five-year survival rate is significantly lower than in patients with low expression (38% vs 47%; p = 0.047). We also found that 70/78 (89.7%) of NSCLC tissues have moderate to strong expression of the N-terminal HIPK2 protein. We detected and cloned a novel HIPK2 isoform 3 and found that its forced overexpression promotes TEAD reporter activity in NSCLC cells. Expressing HIPK2 isoform 3_K228A kinase-dead plasmid failed to increase TEAD reporter activity in NSCLC cells. Next, we showed that two siRNAs targeting HIPK2 decreased HIPK2 isoform 3 and YAP protein levels in NSCLC cells. Degradation of the YAP protein was accelerated after HIPK2 knockdown in NSCLC cells. Inhibition of HIPK2 isoform 3 decreased the mRNA expression of YAP downstream gene CTGF. The specific HIPK2 kinase inhibitor TBID decreased TEAD reporter activity, reduced cancer side populations, and inhibited tumorsphere formation of NSCLC cells. In summary, this study indicates that HIPK2 isoform 3, the main HIPK2 isoform expressed in NSCLC, promotes YAP/TEAD transcriptional activity in NSCLC cells. Our results suggest that HIPK2 isoform 3 may be a potential therapeutic target for NSCLC.

Functional inhibition of heat shock protein 70 by VER-155008 suppresses pleural mesothelioma cell proliferation via an autophagy mechanism

Background: Pleural mesothelioma, a devastating asbestos‐associated malignancy, urgently requires a novel effective therapy. Heat shock protein 70 (HSP70), which is synthesized in the cell response to protein damage, is expected to be a new target for antitumor treatment. In addition to its well‐known protein refolding function, HSP70 regulates cell proliferation through different pathways, including PI3K/AKT/mTOR, and autophagy in malignant cells. In this study, we attempted to clarify the effects of VER‐155008, an HSP70 inhibitor, on pleural mesothelioma.

Methods: Human pleural mesothelioma cell lines 211H, H2452 and H28 were cultured with VER‐155008, and protein expression, cell proliferation, colony formation, cell cycle, synergistic effect with cisplatin, and autophagy induction were analyzed.

Results: In mesothelioma cell lines, VER‐155008 (5.0 μM or more) inhibited cell growth and colony formation, accompanied by G₁ cell cycle arrest. According to western blot analysis, VER‐155008 reduced p‐AKT expression. However, VER‐155008 failed to show a synergistic effect with cisplatin on cell growth. Mesothelioma cells transfected with the novel plasmid pMRX‐IP‐GFP‐LC3‐RFP‐LC3ΔG, which was developed for the quantitative and statistical estimation of macroautophagy, showed enhanced macroautophagy upon treatment with VER‐155008 and gefitinib which is an EGFR‐tyrosine kinase inhibitor. In addition, fetal bovine serum deprivation induced macroautophagy was further enhanced by VER‐155008.

Conclusions: On the basis of these results, functional HSP70 inhibition by VER‐155008 suppressed cell growth in pleural mesothelioma cells, accompanied by enhanced macroautophagy. HSP70 inhibition is thus expected to become a new strategy for treating mesothelioma.

Key points

Significant findings of the study

In pleural mesothelioma cells, inhibition of HSP70 function by VER‐155008 suppressed cell proliferation accompanied by induction of autophagy which was synergistically enhanced under the starvation condition, whereas gefitinib, an EGFR‐TKI, did not show the same synergistic effect in autophagy.

What this study adds

The inhibition of HSP70 induced autophagy and suppressed cell proliferation in mesothelioma cells.

Abstract 1830: Evaluation of anti-tumor effects of VER-155008, a functional inhibitor of HSP70, through macroautophagy in mesothelioma cells

Pleural mesothelioma is a poor prognostic malignancy because the effect of therapies remains limited; and thus, it is urgent to elucidate the pathophysiology leading to newer treatment. Our previous investigation showed that growth of mesothelioma cells was inhibited by suppression of dishevelled-3 on Wnt signaling pathway, accompanied with reduction of heat shock protein 70 (HSP70), which works as a cell-protective molecular chaperon against heat stress, oxidative stress, heavy metals and others, by refolding proteins. Furthermore, HSP70 has been showed to affect cell signaling such as Akt/mTOR pathway, which negatively regulates macroautophagy. This study evaluated effects of VER-155008, an adenosine-derived functional inhibitor of HSP70, on cell growth and macroautophagy of mesothelioma cell lines. Mesothelioma cell lines including MSTO-211H (211H), NCI-H2452 (H2452) and NCI-H28 (H28) were cultured with 0.5-40 µM VER-155008 for cell viability analysis by water-soluble tetrazolium salt-8, colony formation assay, cell cycle analysis and the following analyses. Western blotting confirmed the expression of HSP70, Akt, phosphorylated (p-) Akt, JNK, p-JNK, light chain 3A (LC3A) and lysosome-associated membrane protein 2A (LAMP2A). For evaluation of macroautophagy, a plasmid, pMRX-IP-GFP-LC3-RFP-LC3ΔG, was transfected to mesothelioma cells. The transfected cells generate GFP-LC3-RFP-LC3ΔG, and it was divided into GFP-LC3 and RFP-LC3ΔG by inherent ATG4. GFP-LC3 decreases by macroautophagy activation, while RFP-LC3ΔG serves as an internal control. VER-155008 suppressed cell viability dose-dependently, and colony formation of 211H, H2452 and H28. In 211H and H28 cells, the proportions of cell count in G1 phase significantly increased, accompanied with inhibition of cell growth. In western blot analysis, VER-155008 reduced expression of p-Akt, while the expression of Akt, p-JNK, JNK, LC3A, LAMP2A and HSP70 were not altered. In macroautophagy analysis by the use of mesothelioma cells, which were transfected with the plasmid and stably expressed GFP-LC3-RFP-LC3ΔG, 20 µM VER-155008, 5.0 µM gefitinib and deprivation of fetal bovine serum (FBS) induced macroautophagy. In addition, VER-155008 enhanced FBS-deprivation-induced macroautophagy. From these results, functional inhibition of HSP70 by VER-155008 suppressed cell growth in pleural mesothelioma cells, accompanied with enhancement of macroautophagy.

Citation Format: Kosuke Sakai, Maya Inoue, Hiroaki Nishimura, Shintaro Mikami, Yoshiki Kuwabara, Akitoshi Kojima, Maiko Toda, Yumiko Ogawa, Satoshi Kikuchi, Yusuke Hirata, Yuriko Mikami, Hiroyuki Kyoyama, Gaku Moriyama, Akihiko Gemma, Kazutsugu Uematsu. Evaluation of anti-tumor effects of VER-155008, a functional inhibitor of HSP70, through macroautophagy in mesothelioma cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1830.

Inhibition of cyclin-dependent kinase 7 down-regulates yes-associated protein expression in mesothelioma cells

Cyclin-dependent kinase 7 (CDK7) is a protein kinase that plays a major role in transcription initiation. Yes-associated protein (YAP) is a main effector of the Hippo/YAP signalling pathway. Here, we investigated the role of CDK7 on YAP regulation in human malignant pleural mesothelioma (MPM). We found that in microarray samples of human MPM tissue, immunohistochemistry staining showed correlation between the expression level of CDK7 and YAP (n = 70, r = .513). In MPM cells, CDK7 expression level was significantly correlated with GTIIC reporter activity (r = .886, P = .019). Inhibition of CDK7 by siRNA decreased the YAP protein level and the GTIIC reporter activity in the MPM cell lines 211H, H290 and H2052. Degradation of the YAP protein was accelerated after CDK7 knockdown in 211H, H290 and H2052 cells. Inhibition of CDK7 reduced tumour cell migration and invasion, as well as tumorsphere formation ability. Restoration of the CDK7 gene rescued the YAP protein level and GTIIC reporter activity after siRNA knockdown in 211H and H2052 cells. Finally, we performed a co-immunoprecipitation analysis using an anti-YAP antibody and captured the CDK7 protein in 211H cells. Our results suggest that CDK7 inhibition reduces the YAP protein level by promoting its degradation and suppresses the migration and invasion of MPM cells. Cyclin-dependent kinase 7 may be a promising therapeutic target for MPM.

Vascular Ehlers-Danlos Syndrome with a Novel Missense Mutation in COL3A1: A Man in His 50s with Aortic Dissection after Interventional Treatment for Hemothorax as the First Manifestation

Type III collagen is the major protein in the walls of blood vessels and hollow organs; it is decreased in patients with vascular Ehlers-Danlos syndrome (EDS). A 52-year-old man was admitted for severe back pain, and right hemothorax was suspected by chest computed tomography. Immediately after embolization for bleeding bronchial artery, aortic dissection occurred and was treated conservatively in the intensive-care unit. Vascular EDS with a mutation of COL3A1 cDNA (c.3175G>A) was diagnosed. When vascular EDS is suspected, the patient should be treated prophylactically, and a genetic examination should be performed to confirm the diagnosis.

Synergistic effect of targeting dishevelled-3 and the epidermal growth factor receptor-tyrosine kinase inhibitor on mesothelioma cells in vitro

It was previously revealed that Wnt signaling is activated in mesothelioma cells. Although epidermal growth factor receptor (EGFR) is expressed in mesothelioma cells, EGFR-tyrosine kinase inhibitors (TKIs) are not effective for mesothelioma treatment. However, in non-small cell lung cancer, the blocking of Wnt signaling has been identified to enhance the anticancer effect of EGFR-TKIs. To confirm the anticancer effect of blocking Wnt signaling in combination with EGFR-TKI treatment in mesothelioma, the present study evaluated the effect of simultaneous suppression of human dishevelled-3 (Dvl-3) expression with Dvl-3 small interfering RNA (siRNA) and of EGFR inhibition with gefitinib on mesothelioma cell viability. Mesothelioma cell lines with and without β-catenin gene expression were transfected with Dvl-3 siRNA and were cultured with gefitinib, and cell viability, colony formation and cell cycle analyses were performed. Dvl-3 siRNA downregulated the expression of Dvl-3 in mesothelioma cells. The combination of Dvl-3 siRNA with gefitinib acted synergistically to induce concomitant suppression of cell viability and colony formation, suggesting that inhibition of Wnt signaling by downregulating Dvl-3 with siRNA and inhibiting EGFR with gefitinib leads to significant antitumor effects.

Evaluation of pulmonary function using single-breath-hold dual-energy computed tomography with xenon: Results of a preliminary study

Xenon-enhanced dual-energy computed tomography (xenon-enhanced CT) can provide lung ventilation maps that may be useful for assessing structural and functional abnormalities of the lung. Xenon-enhanced CT has been performed using a multiple-breath-hold technique during xenon washout. We recently developed xenon-enhanced CT using a single-breath-hold technique to assess ventilation. We sought to evaluate whether xenon-enhanced CT using a single-breath-hold technique correlates with pulmonary function testing (PFT) results.Twenty-six patients, including 11 chronic obstructive pulmonary disease (COPD) patients, underwent xenon-enhanced CT and PFT. Three of the COPD patients underwent xenon-enhanced CT before and after bronchodilator treatment. Images from xenon-CT were obtained by dual-source CT during a breath-hold after a single vital-capacity inspiration of a xenon-oxygen gas mixture. Image postprocessing by 3-material decomposition generated conventional CT and xenon-enhanced images.Low-attenuation areas on xenon images matched low-attenuation areas on conventional CT in 21 cases but matched normal-attenuation areas in 5 cases. Volumes of Hounsfield unit (HU) histograms of xenon images correlated moderately and highly with vital capacity (VC) and total lung capacity (TLC), respectively (r = 0.68 and 0.85). Means and modes of histograms weakly correlated with VC (r = 0.39 and 0.38), moderately with forced expiratory volume in 1 second (FEV1) (r = 0.59 and 0.56), weakly with the ratio of FEV1 to FVC (r = 0.46 and 0.42), and moderately with the ratio of FEV1 to its predicted value (r = 0.64 and 0.60). Mode and volume of histograms increased in 2 COPD patients after the improvement of FEV1 with bronchodilators. Inhalation of xenon gas caused no adverse effects.Xenon-enhanced CT using a single-breath-hold technique depicted functional abnormalities not detectable on thin-slice CT. Mode, mean, and volume of HU histograms of xenon images reflected pulmonary function. Xenon images obtained with xenon-enhanced CT using a single-breath-hold technique can qualitatively depict pulmonary ventilation. A larger study comprising only COPD patients should be conducted, as xenon-enhanced CT is expected to be a promising technique for the management of COPD.

Evaluation of serum levels of carcinoembryonic antigen in allergic bronchopulmonary aspergillosis

BACKGROUND

The serum level of carcinoembryonic antigen (CEA) is a marker of malignant disease but can also be increased in benign diseases. Patients with allergic bronchopulmonary aspergillosis (ABPA) have bronchial asthma showing a wide variety of radiological findings. We measured serum CEA levels in patients with ABPA and evaluated the relationships of serum CEA levels with peripheral blood eosinophil counts, total blood levels of immunoglobin (Ig) E, and findings of computed tomography (CT) in ABPA.

METHODS

The subjects were 13 patients (6 men and 7 women aged 34 to 76 years) who had been treated for ABPA at our hospital. Serum levels of CEA, peripheral blood eosinophil counts, total blood IgE levels, and CT findings were examined before and after treatment with prednisolone.

RESULTS

Before the start of the treatment 7 of 13 patients had serum CEA levels higher than the upper limit of normal. The serum CEA level was not correlated with eosinophil counts or total IgE values. Serum CEA levels were examined after treatment in 9 patients and were found to have significantly decreased as pulmonary consolidation improved. Furthermore, serum CEA levels before treatment in patients with pulmonary consolidation were significantly higher than those in patients without consolidation.

CONCLUSION

Serum CEA levels are elevated in some patients with ABPA; these elevations might be associated with consolidation in the lung. Elevated serum CEA levels decrease as the consolidation decreases after treatment. The elevation of serum CEA might be attributed to the presence of local inflammation in the lung.