Molecular targeted agents in non-small-cell lung cancer

Although advances in chemotherapy have provided some improvement in overall survival for patients with advanced non-small-cell lung cancer (NSCLC), outcomes remain poor. Several targeted therapies for lung cancer are in development, and it is hoped that these new approaches will continue to improve survival for patients with advanced NSCLC. These new therapies are targeted specifically to the molecular pathways and processes that characterize tumor growth and progression, including uncontrolled cell growth, invasion, metastasis, angiogenesis, and resistance to apoptosis. Some molecules, such as protein kinase C and the epidermal growth factor receptor-tyrosine kinase, play central roles in cellular activity and are involved in many of the different signaling pathways underlying malignant transformation. Other molecules are dedicated to a specific process, such as the role of vascular endothelial growth factor in angiogenesis. New approaches use a variety of technologies to target these molecules, including small-molecule inhibitors, antibodies, and antisense oligonucleotides, among others. Many of these therapies are currently being tested alone or in combination with each other and with standard treatments for a variety of tumors. This article summarizes data on treatment of NSCLC with some of the agents that are the furthest along in clinical development. It is possible to envision a future in which a combination of therapies treat lung cancer on multiple fronts, significantly enhancing tumor responses and improving survival beyond current expectations.     

Targeting cancer stem cells via integrin β4

Integrins mediate cell-cell interactions and communication with the extracellular matrix (ECM). These transmembrane protein receptors allow binding between a cell and its surroundings, initiating a breadth of intracellular signaling resulting in proliferation, differentiation, survival, or migration. Such responses have made integrins an attractive target for cancer therapy. Self-renewing and highly tumorigenic cancer stem cells (CSCs) are most resistant to traditional radiation treatment and chemotherapy, and therefore may contribute directly to the metastasis and relapse of the disease. In both the 4T1 mouse metastatic mammary tumor model and SCC7 head and neck squamous cell carcinoma model, integrin β4 (ITGB4) was expressed on ALDH^high 4T1 and SCC7 CSCs. Using two immunological approaches, we targeted ITGB4 through 1) ITGB4 protein-pulsed dendritic cell (ITGB4-DC) vaccination or 2) via anti-CD3/anit-ITGB4 bispecific antibody (ITGB4 BiAb)-armed T cell adoptive transfer. These two therapies reduced ITGB4-expressing CSCs and inhibited local tumor growth and lung metastasis through ITGB4 specific cellular and humoral immune responses. Additionally, the combination of anti-PD-L1 immunotherapy with our two ITGB4-targeted approaches significantly improved treatment efficacy. We also found increased concentrations of serum IFN-γ and IL-6 in the 4T1 and SCC7 models which may help define future directions of this ITGB4-targeted study. Together, these results emphasize ITGB4 as a practical CSC immunological target with possible therapeutic benefits across tumor types with high ITGB4 expression.     

Perspective on the development of new agents in thoracic cancers

The development of several targeted agents that play a critical role in the growth and survival of carcinomas has paved the way for a new era in the treatment of patients with thoracic malignancies. The novel antimetabolite pemetrexed has emerged as a key agent in the treatment of advanced malignant pleural mesothelioma (MPM). Inhibitors of the epidermal growth factor receptor (EGFR) are one of many promising targeted therapies for non-small-cell lung cancer (NSCLC). By utilizing agents that specifically target the biochemical and molecular changes underlying cancer, it is possible to envision a future in which combinations of therapies treat cancer on multiple fronts, significantly enhancing tumor responses and improving survival beyond current expectations.     

Immunological Aspects of Cryoablation of Non–Small Cell Lung Cancer: A Comprehensive Review

In cryoimmunotherapy, target tumors are treated with cryoablation to generate antitumor immune responses. Because immune checkpoint inhibitors have demonstrated that lung cancer can be an immunotherapy-responsive disease, there has been renewed interest in the immunological aspects of cryoablation of lung cancer. Herein, we review preclinical and clinical trials of cryoablation of primary lung tumors. We examine the magnitude of cryoablation-induced antitumor immune responses and the synergy between cryoablation and either other immunotherapies or molecular targeted therapies to improve treatment responses in advanced lung cancer. We further discuss a rationale for the addition of cryoablation to immune checkpoint inhibitors for the treatment of advanced lung cancer, which is currently under clinical investigation.     

Emerging epigenetic targets and therapies in cancer medicine

Abnormalities in the epigenetic regulation of chromatin structure and function can lead to aberrant gene expression and cancer development. Consequently, epigenetic therapies aim to restore normal chromatin modification patterns through the inhibition of various components of the epigenetic machinery. Histone deacetylase and DNA methyltransferase inhibitors represent the first putative epigenetic therapies; however, these agents have pleiotropic effects and it remains unclear how they lead to therapeutic responses. More recently, drugs that inhibit histone methyltransferases were developed, perhaps representing more specific agents. We review emerging epigenetic targets in cancer and present recent models of promising epigenetic therapies. SIGNIFICANCE: The use of DNA methyltransferase and histone deacetylase inhibitors in patients has validated the use of drugs targeted to epigenetic enzymes and strengthened the need for development of additional therapies. In this review, we summarize recently discovered epigenetic abnormalities, their implications for cancer, and the approaches taken for discovering small-molecule inhibitors targeting various properties of the epigenetic machinery.     

Immunologic approaches for the treatment of multiple myeloma

The FDA approval of two monoclonal antibodies in 2015 has heralded a new era of targeted immunotherapies for multiple myeloma (MM). In this review we discuss the recent approaches using different immunological components to treat MM. In particular, we review current monoclonal antibody based therapies, engineered T- and NK cell products, ‘off-target’ immunomodulation, and strategies utilizing allogeneic cell transplantation in MM. We discuss how an immunologic approach offers promise for the treatment of this genetically heterogeneous disease, and how patients with acquired drug resistance may particularly benefit from these therapies. We also describe some of the limitations of the current strategies and speculate on the future of personalized immunotherapies for MM.     

Molecular (de)regulation and cancer: new therapeutic strategies

The considerable progress of molecular biology within the past twenty years has permitted a more and more detailed characterization of the molecular mechanisms regulating cell proliferation. The corollary to these discoveries has been the identification of different deregulations yielding to cell transformation and cancer. The goal of this review is to present new therapeutic tools that stemmed from the now well understood logic underlying cell transformation. These tools, based on the intimate understanding of signalization pathways, aim at restoring the molecular controls which had been abrogated during the process of cell transformation. We present a survey of these new proposed therapeutic strategies. These new approaches will probably allow the clinician, in the near future, to combine traditional therapies with more targeted ones, and thus to limit side effects often associated with classical cancer therapies, while improving the overall effect of the treatment.     

Narrowing the focus: Therapeutic cell surface targets for refractory triple-negative breast cancer

Triple-negative breast cancer (TNBC) is defined as a type of breast cancer with lack of expression of estrogen receptor, progesterone receptor and human epidermal growth factor 2 protein. In comparison to other types of breast cancer, TNBC characterizes for its aggressive behavior, more prone to early recurrence and a disease with poor response to molecular target therapy. Although TNBC is identified in only 25%-30% of American breast cancer cases annually, these tumors continue to be a therapeutic challenge for clinicians for several reasons: Tumor heterogeneity, limited and toxic systemic therapy options, and often resistance to current standard therapy, characterized by progressive disease on treatment, residual tumor after cytotoxic chemotherapy, and early recurrence after complete surgical excision. Cell-surface targeted therapies have been successful for breast cancer in general, however there are currently no approved cell-surface targeted therapies specifically indicated for TNBC. Recently, several cell-surface targets have been identified as candidates for treatment of TNBC and associated targeted therapies are in development. The purpose of this work is to review the current clinical challenges posed by TNBC, the therapeutic approaches currently in use, and provide an overview of developing cell surface targeting approaches to improve outcomes for treatment resistant TNBC.     

Targeting complex,adaptive responses in melanoma therapy

Our understanding of the complex, adaptive mechanisms of response to targeted therapies in metastatic melanoma is now leading to more effective combination treatments. These include the simultaneous inhibition of signalling pathways and metabolic programmes, as well as epigenetic mechanisms or immunological checkpoints. We review the latest pre-clinical and clinical results of strategies to delay tumor progression through combination approaches, and also highlight some of the problems ahead, including patient stratification, the complexity of targeting adaptive responses, and the management of more severe toxicities that result from double and triple-drug treatments.     

Resistance to anticancer immunity in cancer patients: potential strategies to reverse resistance

In the 1990s, the application of immunotherapy approaches to target cancer cells resulted in significant clinical responses in patients with advanced malignancies who were refractory to conventional therapies. While early immunotherapeutics were focused on T cell-mediated cytotoxic activity, subsequent efforts were centered on targeted antibody-mediated anticancer therapy. The initial success with antibody therapy encouraged further studies and, consequently, there are now more than 25 FDA-approved antibodies directed against a range of targets. Although both T cell and antibody therapies continue to result in significant clinical responses with minimal toxicity, a significant subset of patients does not respond to immunotherapy and another subset develops resistance following an initial response. This review is focused on describing examples showing that cancer resistance to immunotherapies indeed occurs. In addition, it reviews the mechanisms being used to overcome the resistance to immunotherapies by targeting the tumor cell directly and/or the tumor microenvironment.     

溶瘤腺病毒肿瘤靶向治疗：从实验室到临床

过去几十年从实验室到临床对溶瘤腺病毒进行了广泛的研究.有多种策略增强溶瘤腺病毒的肿瘤靶向性,包括将腺病毒基因组中参与细胞周期节点调控的功能基因(如E1A或E1B)进行突变或(和)利用肿瘤特异性启动子调控E1A基因的靶向转录调控,利用不同血清型腺病毒或RGD基序改变溶瘤腺病毒进入肿瘤细胞方式的靶向转导调控,以及利用细胞载体将溶瘤腺病毒传送至远处的肿瘤部位.溶瘤腺病毒作为一种载体,输送免疫调节基因或治疗性基因,通过增强抗肿瘤免疫,或引起肿瘤细胞凋亡、自杀等产生协同抗肿瘤效应.溶瘤腺病毒临床试验涉及到多种实体瘤,显示其临床应用是安全的,毒性作用轻至中度,患者能很好耐受,但有明确客观抗肿瘤反应的临床病例较少见,联合诸如化、放疗等治疗方法有助于提高临床效果. 未来的方向应强化溶瘤腺病毒免疫学相关机制的研究、突破妨碍溶瘤腺病毒研究的一些技术性瓶颈、优化细胞载体、提高溶瘤腺病毒远处传递的靶向性,以及寻找更具潜能的肿瘤干细胞作为靶点.此外,需要扩大临床试验的研究范围和加强与其他治疗方式特别是免疫治疗联合应用的研究.     

Targeting the tumor microenvironment to enhance antitumor immune responses

The identification of tumor-specific antigens and the immune responses directed against them has instigated the development of therapies to enhance antitumor immune responses. Most of these cancer immunotherapies are administered systemically rather than directly to tumors. Nonetheless, numerous studies have demonstrated that intratumoral therapy is an attractive approach, both for immunization and immunomodulation purposes. Injection, recruitment and/or activation of antigen-presenting cells in the tumor nest have been extensively studied as strategies to cross-prime immune responses. Moreover, delivery of stimulatory cytokines, blockade of inhibitory cytokines and immune checkpoint blockade have been explored to restore immunological fitness at the tumor site. These tumor-targeted therapies have the potential to induce systemic immunity without the toxicity that is often associated with systemic treatments. We review the most promising intratumoral immunotherapies, how these affect systemic antitumor immunity such that disseminated tumor cells are eliminated, and which approaches have been proven successful in animal models and patients.     

Targeting inflammation in pancreatic cancer: Clinical translation

Preclinical modelling studies are beginning to aid development of therapies targeted against key regulators of pancreatic cancer progression. Pancreatic cancer is an aggressive, stromally-rich tumor, from which few people survive. Within the tumor microenvironment cellular and extracellular components exist, shielding tumor cells from immune cell clearance, and chemotherapy, enhancing progression of the disease. The cellular component of this microenvironment consists mainly of stellate cells and inflammatory cells. New findings suggest that manipulation of the cellular component of the tumor microenvironment is possible to promote immune cell killing of tumor cells. Here we explore possible immunogenic therapeutic strategies. Additionally extracellular stromal elements play a key role in protecting tumor cells from chemotherapies targeted at the pancreas. We describe the experimental findings and the pitfalls associated with translation of stromally targeted therapies to clinical trial. Finally, we discuss the key inflammatory signal transducers activated subsequent to driver mutations in oncogenic Kras in pancreatic cancer. We present the preclinical findings that have led to successful early trials of STAT3 inhibitors in pancreatic adenocarcinoma.     

Combining immunotherapy and targeted therapies in cancer treatment

During the past two decades, the paradigm for cancer treatment has evolved from relatively nonspecific cytotoxic agents to selective, mechanism-based therapeutics. Cancer chemotherapies were initially identified through screens for compounds that killed rapidly dividing cells. These drugs remain the backbone of current treatment, but they are limited by a narrow therapeutic index, significant toxicities and frequently acquired resistance. More recently, an improved understanding of cancer pathogenesis has given rise to new treatment options, including targeted agents and cancer immunotherapy. Targeted approaches aim to inhibit molecular pathways that are crucial for tumour growth and maintenance; whereas, immunotherapy endeavours to stimulate a host immune response that effectuates long-lived tumour destruction. Targeted therapies and cytotoxic agents also modulate immune responses, which raises the possibility that these treatment strategies might be effectively combined with immunotherapy to improve clinical outcomes.     

L523S,an RNA-binding protein as a potential therapeutic target for lung cancer

Approaches to vaccine-based immunotherapy of human cancer may ultimately require targets that are both tumour-specific and immunogenic. In order to generate specific antitumour immune responses to lung cancer, we have sought lung cancer-specific proteins that can be targeted for adjuvant vaccine therapy. By using a combination of cDNA subtraction and microarray analysis, we previously reported the identification of an RNA-binding protein within the KOC family, L523S, to be overexpressed in squamous cell cancers of the lung. We show here that L523S exhibits significant potential for vaccine immunotherapy of lung cancer. As an oncofetal protein, L523S is normally expressed in early embryonic tissues, yet it is re-expressed in a high percentage of nonsmall cell lung carcinoma. The specificity of L523S expression in lung cancer was demonstrated by both mRNA and protein measurements using real-time PCR, Western blot, and immunohistochemistry analyses. Furthermore, we show that immunological tolerance of L523S is naturally broken in lung cancer patients, as evidenced by detectable antibody responses to recombinant L523S protein in eight of 17 lung pleural effusions from lung cancer patients. Collectively, our studies suggest that L523S may be an important marker of malignant progression in human lung cancer, and further suggest that treatment approaches based on L523S as an immunogenic target are worthy of pursuit.     

New systemic treatment options for metastatic renal‐cell carcinoma in the era of targeted therapies

Advances in understanding the biology and genetics of renal‐cell carcinomas have led to the development of novel targeted therapies for the treatment of metastatic renal‐cell cancer. Previously the systemic approaches were limited to cytokine therapies that were modest in their clinical benefits and at the expense of significant toxicities. Investigational treatments with allogeneic bone marrow transplantation were equally toxic and resulted in significant morbidity and mortality. The development of targeted therapy has revolutionized the treatment of metastatic renal‐cell cancer with more meaningful outcomes. This review aims to provide a detailed discussion of the clinical benefits of targeted therapies such as sunitinib, sorafenib, temsirolimus, everolimus, bevacizumab, and some of the newer agents in clinical trial development. The efficacy of these compounds in terms of response, survival and clinical benefit are explored as well as their toxicities. The role of surgery in metastatic renal‐cell carcinoma is reviewed in the context of cytoreductive therapy and resection of solitary and oligometastatic disease. Ongoing studies in the adjuvant setting following curative resection are also reviewed. The availability of targeted therapies has led to their rapid adoption as frontline therapy over traditional cytokine therapy, thus bringing more optimistic and hopeful therapeutic options in a condition where historically, systemic treatments have been relatively unsatisfactory and disappointing.     

Reappraisal of the role of bevacizumab in the therapeutic strategy in advanced renal cell carcinoma

Increased understanding of the molecular pathophysiology of metastatic renal cell carcinoma (mRCC) has led to development of antiangiogenic therapies in the past 5 years that significantly improved the prognosis. Vascular endothelial growth factor (VEGF) is a major growth factor in tumor angiogenesis and is implicated in tumor progression of several types of cancer, including mRCC. Use of 2 distinct approaches resulted in clinical efficacy in blocking the VEGF pathway: small molecule tyrosine kinase inhibitors (sunitinib, sorafenib, axitinib, pazopanib) and the humanized anti-VEGF monoclonal antibody bevacizumab that binds circulating VEGF and prevents activation of the VEGF receptor. In the 2 large phase III trials AVOREN and CALGB 90206, bevacizumab combined with interferon alfa demonstrated its efficacy as a first-line therapy in terms of progression-free survival. Nevertheless, in the era of targeted therapies, other studies are still needed to better obtain the maximal clinical benefit of bevacizumab. The aim of this overview is to report the current role of bevacizumab in the treatment of metastatic kidney cancer and to highlight possible combinations or sequential strategies that involve other targeted agents.     

肺癌表皮生长因子受体酪氨酸激酶抑制剂获得性耐药的逆转

以表皮生长因子受体（EGFR）为靶点治疗非小细胞肺癌是治疗肺癌的前沿手段,其产生的获得性耐药限制了靶向药物的发展。目前已有大量的有关EGFR突变耐药的数据,利用这些数据,人们正在探讨克服EGFR靶向治疗耐药的3个基本方法：强化EGFR的抑制、EGFR抑制剂与其他靶向治疗相结合以及通过替代途径改变抗癌治疗方法。     

Molecular therapy targets in lung cancer

Molecular targeted therapies offer great hope in lung cancer because they are supposed to act upon biologic abnormalities specific to cancer cells. In the present review, we will describe the major pathways of tumor cell growth, apoptosis, angiogenesis and invasion as well as the targeted therapies interacting with these pathways. We will provide an overview of the trials involving targeted therapies in lung cancer, along with the specific problems related to the development of these new therapies.     

Survivin-derived peptide epitopes and their role for induction of antitumor immunity in hematological malignancies

The immune system's ability to detect and destroy tumor cells offers an attractive approach to broaden the spectrum of cancer therapies. Survivin, a member of the apoptosis inhibitor protein family, is a tumor antigen, overexpressed in human cancers giving rise to peptides eliciting spontaneous CD8+ and CD4+ responses. Due to its dual function, blockade of apoptosis and regulation of cell division, survivin is directly associated with tumor survival and therefore regarded as an ideal target structure for immunotherapeutic approaches. Strong evidence that survivin acts as a T-cell activating antigen has been collected in recent years and the first clinical trials using survivin-based vaccines aim to prove its therapeutic efficacy in the clinic. We focus on the role of survivin in hematological malignancies, including a list of survivin-derived peptides eliciting potent immune responses.