Overexpression of CD 133 and BCL-2 in non-small cell lung cancer with neuroendocrine differentiation after transformation in ALK rearrangement-positive adenocarcinoma

Targeting of human cancer stem cells predicts efficacy and toxicity of FDA-approved oncology drugs

Cancer remains the leading cause of death worldwide with approved oncology drugs continuing to have heterogenous patient responses and accompanied adverse effects (AEs) that limits effectiveness. Here, we examined >100 FDA-approved oncology drugs in the context of stemness using a surrogate model of transformed human pluripotent cancer stem cells (CSCs) vs. healthy stem cells (hSCs) capable of distinguishing abnormal self-renewal and differentiation. Although a proportion of these drugs had no effects (inactive), a larger portion affected CSCs (active), and a unique subset preferentially affected CSCs over hSCs (selective). Single cell gene expression and protein profiling of each drug's FDA recognized target provided a molecular correlation of responses in CSCs vs. hSCs. Uniquely, drugs selective for CSCs demonstrated clinical efficacy, measured by overall survival, and reduced AEs. Our findings reveal that while unintentional, half of anticancer drugs are active against CSCs and associated with improved clinical outcomes. Based on these findings, we suggest ability to target CSC targeting should be included as a property of early onco-therapeutic development.

ALK inhibitors in cancer: mechanisms of resistance and therapeutic management strategies

Anaplastic lymphoma kinase (ALK) gene rearrangements have been identified as potent oncogenic drivers in several malignancies, including non-small cell lung cancer (NSCLC). The discovery of ALK inhibition using a tyrosine kinase inhibitor (TKI) has dramatically improved the outcomes of patients with ALK-mutated NSCLC. However, the emergence of intrinsic and acquired resistance inevitably occurs with ALK TKI use. This review describes the molecular mechanisms of ALK TKI resistance and discusses management strategies to overcome therapeutic resistance.

Heterogeneity of cancer stem cell-related marker expression is associated with three-dimensional structures in malignant pleural effusion produced by lung adenocarcinoma

INTRODUCTION

Cancer stem cells have been described in lung adenocarcinoma-associated malignant pleural effusion. They show clinically important features, including the ability to initiate new tumours and resistance to treatments. However, their correlation with the three-dimensional tumour structures in the effusion is not well understood.

METHODS

Cell blocks produced from lung adenocarcinoma patients' pleural effusion were examined for cancer stem cell-related markers Nanog and CD133 using immunocytochemistry. The three-dimensional cancer cell structures and CD133 expression patterns were visualized with tissue-clearing technology. The expression patterns were correlated with tumour cell structures, genetic variants and clinical outcomes.

RESULTS

Thirty-nine patients were analysed. Moderate-to-strong Nanog expression was detected in 27 cases (69%), while CD133 was expressed by more than 1% of cancer cells in 11 cases (28%). Nanog expression was more homogenous within individual specimens, while CD133 expression was detected in single tumour cells or cells within small clusters instead of larger structures in 8 of the 11 positive cases (73%). Although no statistically significant correlation between the markers and tumour genetic variants or patient survival was observed, we recorded seven cases with follow-up specimens after cancer treatment, and four (57%) showed a change in stem cell-related marker expression corresponding to treatment response.

CONCLUSIONS

Lung adenocarcinoma cells in the pleural effusion show variable expression of cancer stem cell-related markers, some showing a correlation with the size of cell clusters. Their expression level is potentially correlated with cancer treatment effects.

Tumor heterogeneity from the viewpoint of pathologists

Morphological and functional heterogeneity are found in tumors, with the latter reflecting the different levels of resistance against antitumor therapies. In a therapy-resistant subpopulation, the expression levels of differentiation markers decrease, and those of immature markers increase. In addition, this subpopulation expresses genes involved in drug metabolism, such as aldehyde dehydrogenase 1A1 (ALDH1A1). Because of their similarity to stem cells, cells in the latter therapy-resistant subpopulation are called cancer stem cells (CSCs). Like normal stem cells, CSCs were originally thought not to arise from non-CSCs, but this hierarchical model is too simple. It is now believed that CSCs are generated from non-CSCs. The plasticity of tumor phenotypes between CSCs and non-CSCs causes difficulty in completely curing tumors. In this review, focusing on ALDH1A1 as a marker for CSCs or immature tumor cells, the dynamics of ALDH1A1-expressing tumor cells and their regulatory mechanisms are described, and the plausible regulatory mechanisms of plasticity of ALDH1A1 expression phenotype are discussed. Genetic mutations are a significant factor for tumorigenesis, but non-mutational epigenetic reprogramming factors yielding tumor heterogeneity are also crucial in determining tumor characteristics. Factors influencing non-mutational epigenetic reprogramming in tumors are also discussed.

Genomic and transcriptomic analysis of neuroendocrine transformation in ALK-rearranged lung adenocarcinoma after treatments with sequential ALK inhibitors: a brief report

Introduction

Neuroendocrine (NE) transformation has been reported in patients with ALK-rearranged NSCLC after ALK inhibition, but unlike EGFR-mutant NSCLC, the exact mechanism of NE transformation in ALK-rearranged NSCLC is poorly studied.

Methods

We collected the matched pre- and post-transformation samples from a patient with ALK-rearranged lung adenocarcinoma (LUAD) and performed targeted panel sequencing, whole exome sequencing, and bulk RNA sequencing.

Results

Multiple mutations were shared between the pretransformation and post-transformation samples. Neither RB1 nor TP53 mutation was detected, but CDKN2A deletion and CDK4 amplification were found instead. Mismatch repair-associated mutational signature was significantly enriched after transformation. Genes associated with Notch signaling and PI3K/AKT pathway were significantly up-regulated, whereas genes related to lymphocyte activation and NF-kB signaling were down-regulated. Signatures relating to homologous recombination, mismatch repair, and Notch signaling pathways were enriched, which were further validated in The Cancer Genome Atlas cohorts. Macrophages M2 were found to have prominently higher abundance in the tumor immune microenvironment after NE transformation.

Conclusions

The mechanism of NE transformation in ALK-rearranged LUAD may be different from that in EGFR-mutant LUAD.

The Resistance Mechanisms and Treatment Strategies for ALK-Rearranged Non-Small Cell Lung Cancer

Anaplastic lymphoma kinase (ALK) is a validated molecular target for non-small-cell lung cancer (NSCLC). The use of tyrosine kinase inhibitors (TKIs) has led to significantly improved survival benefits. However, the clinical benefits of targeting ALK using TKIs are limited due to the emergence of drug resistance. The landscape of resistance mechanisms and treatment decisions has become increasingly complex. Therefore, continued research into new drugs and combinatorial therapies is required to improve outcomes in NSCLC. In this review, we explore the resistance mechanisms of ALK TKIs in advanced NSCLC in order to provide a theoretical basis and research ideas for solving the problem of ALK drug resistance.

Study on effects of miR-141-3p in proliferation, migration, invasion and apoptosis of colon cancer cells by inhibiting Bcl2

PURPOSE

This study aimed to investigate the relationship between miR-141-3p and B lymphocyte-2 gene (Bcl2) gene and its biological behavior on colon cancer cell line SW480.

METHODS

qRT-PCR was used to detect the expression level of miR-141-3p in colon cancer tissues and adjacent tissues, as well as in colon cancer cell line and normal human colonic epithelial cell line FHC. MTT assay, wound assay, and Transwell demonstrated the effects of miR-141-3p on colon cancer proliferation, migration and invasion. Targetscan7.1 predictive software and dual luciferase reporter assays were used to detect the targeted regulation of miR-141-3p on the apoptosis-related gene Bcl2. MTT assay, wound assay, Transwell and flow cytometry were used to detect the effect of Bcl2 on miR-141-3p on colon cancer proliferation, migration, invasion and apoptosis.

RESULTS

Compared with adjacent tissues, the expression of miR-141-3p in colon cancer tissues was significantly down-regulated. Colon cancer patients with low expression of miR-141-3p had poorer prognosis. Compared with normal colonic epithelial cells, miR-141-3p expression was significantly down-regulated in colon cancer cell lines, and overexpression of miR-141-3p significantly attenuated the proliferation, migration and invasion of colon cancer cells. Knockdown of miR-141-3p significantly promoted the proliferation, migration and invasion of colon cancer cells. miR-141-3p targets the negative regulation of Bcl2. Knockdown of Bcl2 significantly attenuated the promotion of miR-141-3p inhibitor on proliferation, migration and invasion of colon cancer cells and inhibition of apoptosis. Knockdown of Bcl2 significantly enhanced the inhibition effect of miR-141-3p inhibitor on proliferation, migration and invasion of colon cancer cells.

CONCLUSIONS

In conclusion, miR-141-3p can inhibit the cancer by regulating Bcl2, and miR-141-3p has the potential to become a potential therapeutic target for colon cancer.

Primary resistance to alectinib in a patient with STRN-ALK-positive non-small cell lung cancer: A case report

Anaplastic lymphoma kinase (ALK) rearrangements are drivers of a subset of non‐small cell lung cancer (NSCLC). The rapid progression of ALK inhibitors has significantly prolonged the progression‐free survival of patients with ALK gene‐sensitive mutations. However, the response of patients with rare ALK rearrangements to tyrosine kinase inhibitors remains unknown. Here, we report a rare case of striatin (STRN)‐ALK‐positive NSCLC showing primary resistance to first‐line therapy alectinib and limited clinical activity of crizotinib in the alectinib‐resistant setting.

Transformational Changes Between Non-Small Cell and Small Cell Lung Cancer-Biological and Clinical Relevance-A Review

During the course of therapy, patients with small cell lung cancer have been noted to develop transformation to non-small cell lung cancer and conversely, patients with non-small cell lung cancer have had transformation to small cell lung cancer or other non-small cell histologies. Transformation may occur after prior tyrosine kinase inhibitors, chemotherapy, immunotherapy or radiation therapy. These changes reflect on the overlapping biology of these cell types and the clinical need for re-biopsy at times of disease progression. The optimum therapy after transformation will depend upon prior therapies received, the functional capacity of the patient, and further research to define the best therapy options.

Cancer Stem Cells-Origins and Biomarkers: Perspectives for Targeted Personalized Therapies

The use of biomarkers in diagnosis, therapy and prognosis has gained increasing interest over the last decades. In particular, the analysis of biomarkers in cancer patients within the pre- and post-therapeutic period is required to identify several types of cells, which carry a risk for a disease progression and subsequent post-therapeutic relapse. Cancer stem cells (CSCs) are a subpopulation of tumor cells that can drive tumor initiation and can cause relapses. At the time point of tumor initiation, CSCs originate from either differentiated cells or adult tissue resident stem cells. Due to their importance, several biomarkers that characterize CSCs have been identified and correlated to diagnosis, therapy and prognosis. However, CSCs have been shown to display a high plasticity, which changes their phenotypic and functional appearance. Such changes are induced by chemo- and radiotherapeutics as well as senescent tumor cells, which cause alterations in the tumor microenvironment. Induction of senescence causes tumor shrinkage by modulating an anti-tumorigenic environment in which tumor cells undergo growth arrest and immune cells are attracted. Besides these positive effects after therapy, senescence can also have negative effects displayed post-therapeutically. These unfavorable effects can directly promote cancer stemness by increasing CSC plasticity phenotypes, by activating stemness pathways in non-CSCs, as well as by promoting senescence escape and subsequent activation of stemness pathways. At the end, all these effects can lead to tumor relapse and metastasis. This review provides an overview of the most frequently used CSC markers and their implementation as biomarkers by focussing on deadliest solid (lung, stomach, liver, breast and colorectal cancers) and hematological (acute myeloid leukemia, chronic myeloid leukemia) cancers. Furthermore, it gives examples on how the CSC markers might be influenced by therapeutics, such as chemo- and radiotherapy, and the tumor microenvironment. It points out, that it is crucial to identify and monitor residual CSCs, senescent tumor cells, and the pro-tumorigenic senescence-associated secretory phenotype in a therapy follow-up using specific biomarkers. As a future perspective, a targeted immune-mediated strategy using chimeric antigen receptor based approaches for the removal of remaining chemotherapy-resistant cells as well as CSCs in a personalized therapeutic approach are discussed.

Relationship between Cancer Stem Cell Marker CD133 and Cancer Germline Antigen Genes in NCI-H292 Lung Cancer Cells

Background

Previous studies have shown that lung cancer stem cells express CD133 and that certain cancer stem cells express cancer germline antigens (CGAs). The transcriptional regulation of CD133 is complicated and poorly understood. We investigated CD133 and CGA expression in a non-small cell lung cancer cell line.

Methods

The expression levels of CD133 and CGAs (MAGE-6, GAGE, SSX, and TRAG-3) were measured in an NCI-H292 lung cancer cell line. The methylation status of the CD133 gene promoter region was analyzed. The expression levels and promoter methylation statuses of CD133 and CGAs were confirmed by treatment with the demethylating agent 5-aza-2′-deoxycytidine (ADC).

Results

After treatment with ADC, CD133 expression was no longer detected. MAGE-6 and TRAG-3 were detected before ADC treatment, while GAGE and SSX were not detected. ADC treatment upregulated MAGE-6 and TRAG-3 expression, while GAGE expression was still undetected after treatment, and only weak SSX expression was observed. GAGE expression was not correlated with expression of CD133, while the levels of expression of MAGE-6, TRAG-3, and SSX were inversely correlated with CD133 expression.

Conclusion

These results showed that CD133 expression can be regulated by methylation. Thus, the demethylation of the CD133 promoter may compromise the treatment of lung cancer by inactivating cancer stem cells and/or activating CGAs.