Therapy-induced normal tissue damage promotes breast cancer metastasis

Disseminated tumor cells frequently exhibit a period of dormancy, rendering them chemotherapy insensitive; conversely, the systemic delivery of chemotherapies can result in normal tissue damage. Using multiple mouse and human breast cancer models, we demonstrate that prior chemotherapy administration enhances metastatic colonization and outgrowth. In vitro, chemotherapy-treated fibroblasts display a pro-tumorigenic senescence-associated secretory phenotype (SASP) and are effectively eliminated by targeting the anti-apoptotic protein BCL-xL. In vivo, chemotherapy treatment induces SASP expression in normal tissues; however, the accumulation of senescent cells is limited, and BCL-xL inhibitors are unable to reduce chemotherapy-enhanced metastasis. This likely reflects that chemotherapy-exposed stromal cells do not enter a BCL-xL-dependent phenotype or switch their dependency to other anti-apoptotic BCL-2 family members. This study highlights the role of the metastatic microenvironment in controlling outgrowth of disseminated tumor cells and the need to identify additional approaches to limit the pro-tumorigenic effects of therapy-induced normal tissue damage.

Has the shortage of fludarabine altered the current paradigm of lymphodepletion in favor of bendamustine?

The most common lymphodepletion regimen used prior to infusion of chimeric antigen receptor-T cells (CAR-T) is cyclophosphamide (CY) in combination with fludarabine (Flu) (CY-FLU). While cyclophosphamide (CY) possesses lymphotoxic effects, it concurrently preserves regulatory T cell activity, potentially affecting the efficacy of CAR-T cells. Moreover, the use of fludarabine (FLU) has been linked to neurotoxicity, which could complicate the early detection of immune effector cell-associated neurotoxicity syndrome (ICANS) observed in CAR-T cell therapy. Given the ongoing shortage of FLU, alternative lymphodepleting agents have become necessary. To date, only a limited number of studies have directly compared different lymphodepleting regimens, and most of these comparisons have been retrospective in nature. Herein, we review the current literature on lymphodepletion preceding CAR-T cell therapies for lymphoid hematologic malignancies, with a specific focus on the use of bendamustine (BEN). Recent evidence suggests that administering BEN before CAR-T cell infusion yields comparable efficacy, possibly with a more favorable toxicity profile when compared to CY-FLU. This warrants further investigation through randomized prospective studies.

The Role of Regulatory T Cells in Cancer Treatment Resistance

Despite tremendous progress in cancer treatment in recent years, treatment resistance is still a major challenge for a great number of patients. One of the main causes is regulatory T lymphocytes (Tregs), which suppress excessive inflammatory responses via the secretion of immunosuppressive cytokines and upregulate the immune checkpoints. Their abundance causes an immunosuppressive reprogramming of the tumor environment, which is ideal for tumor growth and drug inefficiency. Hence, regiments that can regain tumor immunogenicity are a promising strategy to overcome Tregs-mediated drug resistance. However, to develop effective therapeutic regimens, it is essential to understand the molecular mechanisms of Treg-mediated resistance. In this article, we gathered a comprehensive summary of the current knowledge on molecular mechanisms and the role of Tregs in cancer treatment resistance, including cancer immunotherapy, targeted therapy, chemotherapy, and radiotherapy.

Platinum-Based Nanoformulations for Glioblastoma Treatment: The Resurgence of Platinum Drugs?

Current therapies for treating Glioblastoma (GB), and brain tumours in general, are inefficient and represent numerous challenges. In addition to surgical resection, chemotherapy and radiotherapy are presently used as standards of care. However, treated patients still face a dismal prognosis with a median survival below 15-18 months. Temozolomide (TMZ) is the main chemotherapeutic agent administered; however, intrinsic or acquired resistance to TMZ contributes to the limited efficacy of this drug. To circumvent the current drawbacks in GB treatment, a large number of classical and non-classical platinum complexes have been prepared and tested for anticancer activity, especially platinum (IV)-based prodrugs. Platinum complexes, used as alkylating agents in the anticancer chemotherapy of some malignancies, are though often associated with severe systemic toxicity (i.e., neurotoxicity), especially after long-term treatments. The objective of the current developments is to produce novel nanoformulations with improved lipophilicity and passive diffusion, promoting intracellular accumulation, while reducing toxicity and optimizing the concomitant treatment of chemo-/radiotherapy. Moreover, the blood-brain barrier (BBB) prevents the access of the drugs to the brain and accumulation in tumour cells, so it represents a key challenge for GB management. The development of novel nanomedicines with the ability to (i) encapsulate Pt-based drugs and pro-drugs, (ii) cross the BBB, and (iii) specifically target cancer cells represents a promising approach to increase the therapeutic effect of the anticancer drugs and reduce undesired side effects. In this review, a critical discussion is presented concerning different families of nanoparticles able to encapsulate platinum anticancer drugs and their application for GB treatment, emphasizing their potential for increasing the effectiveness of platinum-based drugs.

Emerging Bone Marrow Microenvironment-Driven Mechanisms of Drug Resistance in Acute Myeloid Leukemia: Tangle or Chance?

Simple Summary

Despite high rates of remission obtained with conventional chemotherapy, the persistence of leukemic cells after treatments, eventually exiting in disease relapse, remains the main challenge in acute myeloid leukemia (AML). Increasing evidence indicates that, besides AML cell mutations, stromal and immune cells, as leukemic microenvironment components, may protect AML cells from therapies. Here, we will recapitulate emerging bone marrow (BM) microenvironment-dependent mechanisms of therapy resistance. The understanding of these processes will help find new drug combinations and conceive novel and more effective treatments.

Abstract

Acute myeloid leukemia (AML) has been considered for a long time exclusively driven by critical mutations in hematopoietic stem cells. Recently, the contribution of further players, such as stromal and immune bone marrow (BM) microenvironment components, to AML onset and progression has been pointed out. In particular, mesenchymal stromal cells (MSCs) steadily remodel the leukemic niche, not only favoring leukemic cell growth and development but also tuning their responsiveness to treatments. The list of mechanisms driven by MSCs to promote a leukemia drug-resistant phenotype has progressively expanded. Moreover, the relative proportion and the activation status of immune cells in the BM leukemic microenvironment may vary by influencing their reactivity against leukemic cells. In that, the capacity of the stroma to re-program immune cells, thus promoting and/or hampering therapeutic efficacy, is emerging as a crucial aspect in AML biology, adding an extra layer of complexity. Current treatments for AML have mainly focused on eradicating leukemia cells, with little consideration for the leukemia-damaged BM niche. Increasing evidence on the contribution of stromal and immune cells in response to therapy underscores the need to hold the mutual interplay, which takes place in the BM. A careful dissection of these interactions will help provide novel applications for drugs already under experimentation and open a wide array of opportunities for new drug discovery.

PD-1 blockade therapy augments the antitumor effects of lymphodepletion and adoptive T cell transfer

Lymphodepleting cytotoxic regimens enhance the antitumor effects of adoptively transferred effector and naïve T cells. Although the mechanisms of antitumor immunity augmentation by lymphodepletion have been intensively investigated, the effects of lymphodepletion followed by T cell transfer on immune checkpoints in the tumor microenvironment remain unclear. The current study demonstrated that the expression of immune checkpoint molecules on transferred donor CD4⁺ and CD8⁺ T cells was significantly decreased in lymphodepleted tumor-bearing mice. In contrast, lymphodepletion did not reduce immune checkpoint molecule levels on recipient CD4⁺ and CD8⁺ T cells. Administration of anti-PD-1 antibodies after lymphodepletion and adoptive transfer of T cells significantly inhibited tumor progression. Further analysis revealed that transfer of both donor CD4⁺ and CD8⁺ T cells was responsible for the antitumor effects of a combination therapy consisting of lymphodepletion, T cell transfer and anti-PD-1 treatment. Our findings indicate that a possible mechanism underlying the antitumor effects of lymphodepletion followed by T cell transfer is the prevention of donor T cell exhaustion and dysfunction. PD-1 blockade may reinvigorate exhausted recipient T cells and augment the antitumor effects of lymphodepletion and adoptive T cell transfer.

Lymphopenia-induced lymphoproliferation drives activation of naive T cells and expansion of regulatory populations

Chemotherapy pre-conditioning is an essential component of chimeric antigen receptor transduced cell therapy. Acute lymphopenia-induced proliferation (LIP) is known to be driven primarily by homeostatic cytokines, but little is known on the underlying mechanisms in humans. We undertook phenotypic and transcriptional analysis of T cells undergoing LIP two weeks post-myeloablative autograft stem cell transplantation. Strong IL-7 signaling was reflected in downregulated IL-7R expression on all T cells, including naive cells, along with parallel increased IL-2Rα expression. Notably, activated residual naive cells expressed Fas indicating recent TCR engagement. Moreover, proportion of Ki67 + FoxP3+ Tregs was almost doubled. Transcriptional analysis revealed increased fatty acid metabolism and interferon signaling responses. In contrast, TGF-β signaling was strongly suppressed. Thus, human LIP response is characterized by cytokine and TCR-driven proliferation which drives global T cell activation but also preferentially triggers regulatory cell expansion which may limit tumor-specific immunity. These features indicate potential therapeutic opportunities to manipulate immunotherapy regimens incorporating LIP conditioning protocols.

A phase 1b clinical trial optimizing regulatory T cell depletion in combination with platinum-based chemotherapy in thoracic cancers

Background: Single-agent cyclophosphamide can deplete regulatory T-cells (Treg). We aimed to determine optimal dosing and scheduling of oral cyclophosphamide, alongside pemetrexed-based chemotherapy, to deplete Treg in mesothelioma or non-small-cell lung cancer patients.Methods: 31 Patients received pemetrexed ± cisplatin or carboplatin on day 1 of a 21-day cycle (maximum 6 cycles). From cycle two, patients received cyclophosphamide, 50 mg/day, with intrapatient escalation to maximum 100/150 mg/day alternately. Immunological changes were examined by flow cytometry. Primary endpoint was Treg proportion of CD4⁺ T-cells, with doses tailored to target Treg nadir <4%.Results: Reduction in Treg proportion was observed on day 8 of all cycles, and was not augmented by cyclophosphamide. Few patients achieved the <4% Treg target. Treg proliferation reached nadir one week after chemotherapy, and peaked on day 1 of the subsequent cycle. Efficacy parameters were similar to chemotherapy alone. Seventeen percent of patients ceased cyclophosphamide due to toxicity.Conclusions: Specific Treg depletion to the degree seen with single-agent cyclophosphamide was not observed during pemetrexed-based chemotherapy. This study highlights the poor evidence basis for use of cyclophosphamide as an immunotherapeutic in combination with chemotherapy, and the importance of detailed flow cytometry studies.Trial registration: Clinical trial registration: www.anzctr.org.au identifier is ACTRN12609000260224.

Lymphodepletion strategies to potentiate adoptive T-cell immunotherapy - what are we doing; where are we going?

INTRODUCTION

Adoptive immunotherapy of cancer has evolved from the use of ex vivo expanded lymphokine-activated killer cells and tumor-infiltrating lymphocytes to an increasing array of approaches involving genetically engineered T-cells. A pivotal advance in the enablement of these therapies has been the conditioning of patients with lymphodepleting chemotherapy.A broad range of lymphodepleting regimens has been employed in an effort to improve response rates, without any single consistent approach having emerged. Only a limited number of studies involving small numbers of patients has directly compared two or more regimens, making it challenging to infer which are the preferred agents and dosing schedules. This difficulty is compounded by the fact that both response rate and toxicity appear to be disease-, patient- and T-cell product specific.

EXPERT OPINION

This article surveys clinical experience with lymphodepleting regimens that have been used in conjunction with adoptive T-cell immunotherapy, focussing in particular on studies where different approaches have been employed. Harnessing this limited and evolving clinical experience, we set out to provide potential insights into how an optimal balance may be achieved between efficacy and safety. Intermediate dose fludarabine-based regimens are emerging as an increasingly popular option in an attempt to achieve this goal, although further studies are required to provide definitive evidence.

Mechanisms of Lymphoma Clearance Induced by High-Dose Alkylating Agents

The extraordinary activity of high-dose cyclophosphamide against some high-grade lymphomas was described nearly 60 years ago. Here we address mechanisms that mediate cyclophosphamide activity in bona fide human double-hit lymphoma. We show that antibody resistance within the bone marrow (BM) is not present upon early engraftment but develops during lymphoma progression. This resistance required a high tumor:macrophage ratio, was recapitulated in spleen by partial macrophage depletion, and was overcome by multiple, high-dose alkylating agents. Cyclophosphamide induced endoplasmic reticulum (ER) stress in BM-resident lymphoma cells in vivo that resulted in ATF4-mediated paracrine secretion of VEGFA, massive macrophage infiltration, and clearance of alemtuzumab-opsonized cells. BM macrophages isolated after cyclophosphamide treatment had increased phagocytic capacity that was reversed by VEGFA blockade or SYK inhibition. Single-cell RNA sequencing of these macrophages identified a "super-phagocytic" subset that expressed CD36/FCGR4. Together, these findings define a novel mechanism through which high-dose alkylating agents promote macrophage-dependent lymphoma clearance. SIGNIFICANCE: mAbs are effective against only a small subset of cancers. Herein, we recapitulate compartment-specific antibody resistance and define an ER stress-dependent mechanism induced by high-dose alkylating agents that promotes phagocytosis of opsonized tumor cells. This approach induces synergistic effects with mAbs and merits testing across additional tumor types.See related commentary by Duval and De Palma, p. 834.This article is highlighted in the In This Issue feature, p. 813.

Phase II Study of the PD-1 Inhibitor Pembrolizumab for the Treatment of Relapsed or Refractory Mature T-cell Lymphoma

BACKGROUND

Programmed cell death-1 (PD-1) and programmed death-ligand 1 (PD-L1) are frequently expressed in T-cell lymphomas. This provides a rationale for exploration of immune checkpoint inhibitors in the management of T-cell lymphomas.

PATIENTS AND METHODS

In this phase II single-arm multicenter trial, patients with relapsed or refractory systemic T-cell lymphoma were treated with 200 mg pembrolizumab intravenously every 21 days. The primary endpoint was progression-free survival (PFS). The secondary endpoints were response rate, overall survival, response duration, and safety. We assessed PD-L1, p-AKT expression, and peripheral blood immune cells as potential predictive biomarkers.

RESULTS

Of 18 enrolled patients, 13 were evaluable for the primary endpoint. The trial was halted early after a preplanned interim futility analysis. The overall response rate was 33% (95% confidence interval [CI], 9%-55%); 4 patients achieved a complete response (27%; 95% CI, 5%-49%). The median PFS was 3.2 months (95% CI, 1.2-3.7 months), and the median overall survival was 10.6 months (95% CI, 3.2-100 months). The median duration of response was 2.9 months (95% CI, 0-10.1 months). Two of the 4 complete responders remain in remission > 15 months. Rash was the most common adverse event (17%; n = 3). The most common ≥ grade 3 treatment-emergent adverse events were rash and pneumonitis (11%; n = 2 each). Neither PD-L1 nor p-AKT expression were associated with outcomes. However, a higher relative frequency of CD4⁺ T lymphocytes pre-treatment was associated with improved PFS (hazard ratio, 0.15; 95% CI, 0.03-0.74).

CONCLUSION

Pembrolizumab demonstrated modest single-agent activity in relapsed or refractory T-cell lymphoma.

Potato freeze-thaw solution enhances immune function and antitumor activity in vivo

Although potato extract, derived from various methods, exhibits anticancer, antiviral and anti-parasite activities in vitro and in vivo, the bioactivity of potato solution remains unclear using the freeze-thaw extraction method granted by the State Intellectual Property Office of China. In the present study, a potato freeze-thaw solution (PFTS) was fed to mice with ascites tumor that were pre-treated with cyclophosphamide. The numbers of peripheral white blood cells (WBCs), macrophage phagocytosis, lymphocyte transformation and survival of mice were measured. While mice injected with cyclophosphamide exhibited decreased counts of peripheral WBCs, treatment of the cyclophosphamide-injected mice with PFTS for 10 days significantly increased the number of peripheral WBCs and reversed WBC counts to the normal level, a comparable effect to that of Ganoderma lucidum. In addition, treatment with PFTS for 20 days significantly enhanced peritoneal macrophage phagocytosis and lymphocyte transformation. Lastly, PFTS was noticed to prolong the survival of tumor-bearing mice when compared with that of control mice. Collectively, these data suggested that PFTS, at least in part, enhances immune function and possesses antitumor activity.

A systematic investigation of the maximum tolerated dose of cytotoxic chemotherapy with and without supportive care in mice

Background

Cytotoxic chemotherapeutics form the cornerstone of systemic treatment of many cancers. Patients are dosed at maximum tolerated dose (MTD), which is carefully determined in phase I studies. In contrast, in murine studies, dosages are often based on customary practice or small pilot studies, which often are not well documented. Consequently, research groups need to replicate experiments, resulting in an excess use of animals and highly variable dosages across the literature. In addition, while patients often receive supportive treatments in order to allow dose escalation, mice do not. These issues could affect experimental results and hence clinical translation.

Methods

To address this, we determined the single-dose MTD in BALB/c and C57BL/6 mice for a range of chemotherapeutics covering the canonical classes, with clinical score and weight as endpoints.

Results

We found that there was some variation in MTDs between strains and the tolerability of repeated cycles of chemotherapy at MTD was drug-dependent. We also demonstrate that dexamethasone reduces chemotherapy-induced weight loss in mice.

Conclusion

These data form a resource for future studies using chemotherapy in mice, increasing comparability between studies, reducing the number of mice needed for dose optimisation experiments and potentially improving translation to the clinic.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3677-7) contains supplementary material, which is available to authorized users.

Breakthroughs in modern cancer therapy and elusive cardiotoxicity: Critical research-practice gaps, challenges, and insights

To date, five cancer treatment modalities have been defined. The three traditional modalities of cancer treatment are surgery, radiotherapy, and conventional chemotherapy, and the two modern modalities include molecularly targeted therapy (the fourth modality) and immunotherapy (the fifth modality). The cardiotoxicity associated with conventional chemotherapy and radiotherapy is well known. Similar adverse cardiac events are resurging with the fourth modality. Aside from the conventional and newer targeted agents, even the most newly developed, immune‐based therapeutic modalities of anticancer treatment (the fifth modality), e.g., immune checkpoint inhibitors and chimeric antigen receptor (CAR) T‐cell therapy, have unfortunately led to potentially lethal cardiotoxicity in patients. Cardiac complications represent unresolved and potentially life‐threatening conditions in cancer survivors, while effective clinical management remains quite challenging. As a consequence, morbidity and mortality related to cardiac complications now threaten to offset some favorable benefits of modern cancer treatments in cancer‐related survival, regardless of the oncologic prognosis. This review focuses on identifying critical research‐practice gaps, addressing real‐world challenges and pinpointing real‐time insights in general terms under the context of clinical cardiotoxicity induced by the fourth and fifth modalities of cancer treatment. The information ranges from basic science to clinical management in the field of cardio‐oncology and crosses the interface between oncology and onco‐pharmacology. The complexity of the ongoing clinical problem is addressed at different levels. A better understanding of these research‐practice gaps may advance research initiatives on the development of mechanism‐based diagnoses and treatments for the effective clinical management of cardiotoxicity.

Transfer of in vitro-expanded naïve T cells after lymphodepletion enhances antitumor immunity through the induction of polyclonal antitumor effector T cells

The adoptive transfer of effector T cells combined with lymphodepletion has demonstrated promising antitumor effects in mice and humans, although the availability of tumor-specific T cells is limited. We and others have also demonstrated that the transfer of polyclonal naïve T cells induces tumor-specific effector T cells and enhances antitumor immunity after lymphodepletion. Because tumors have been demonstrated to induce immunosuppressive networks and regulate the function of T cells, obtaining a sufficient number of fully functional naïve T cells that are able to differentiate into tumor-specific effector T cells remains difficult. To establish culture methods to obtain a large number of polyclonal T cells that are capable of differentiating into tumor-specific effector T cells, naïve T cells were activated with anti-CD3 mAbs in vitro. These cells were stimulated with IL-2 and IL-7 for the CD8 subset or with IL-7 and IL-23 for the CD4 subset. Transfer of these hyperexpanded T cells after lymphodepletion showed significant antitumor efficacy, and tumor-specific effector T cells were primed from these expanded T cells in tumor-bearing hosts. Moreover, these ex vivo-expanded T cells maintained T cell receptor diversity and showed long-term persistence of memory against specific tumors. Further analyses revealed that combination therapy consisting of vaccination with dendritic cells that were co-cultured with irradiated whole tumor cells and the transfer of ex vivo-expanded T cells significantly enhanced antitumor immunity. These results indicate that the transfer of ex vivo-expanded polyclonal T cells can be combined with other immunotherapies and augment antitumor effects.

Successful Transfer of Umbilical Cord Blood CD34+ Hematopoietic Stem and Progenitor-derived NK Cells in Older Acute Myeloid Leukemia Patients

Purpose: Older acute myeloid leukemia (AML) patients have a poor prognosis; therefore, novel therapies are needed. Allogeneic natural killer (NK) cells have been adoptively transferred with promising clinical results. Here, we report the first-in-human study exploiting a unique scalable NK-cell product generated ex vivo from CD34⁺ hematopoietic stem and progenitor cells (HSPC) from partially HLA-matched umbilical cord blood units.Experimental Design: Ten older AML patients in morphologic complete remission received an escalating HSPC-NK cell dose (between 3 and 30 × 10⁶/kg body weight) after lymphodepleting chemotherapy without cytokine boosting.Results: HSPC-NK cell products contained a median of 75% highly activated NK cells, with <1 × 10⁴ T cells/kg and <3 × 10⁵ B cells/kg body weight. HSPC-NK cells were well tolerated, and neither graft-versus-host disease nor toxicity was observed. Despite no cytokine boosting being given, transient HSPC-NK cell persistence was clearly found in peripheral blood up to 21% until day 8, which was accompanied by augmented IL15 plasma levels. Moreover, donor chimerism up to 3.5% was found in bone marrow. Interestingly, in vivo HSPC-NK cell maturation was observed, indicated by the rapid acquisition of CD16 and KIR expression, while expression of most activating receptors was sustained. Notably, 2 of 4 patients with minimal residual disease (MRD) in bone marrow before infusion became MRD negative (<0.1%), which lasted for 6 months.Conclusions: These findings indicate that HSPC-NK cell adoptive transfer is a promising, potential "off-the-shelf" translational immunotherapy approach in AML. Clin Cancer Res; 23(15); 4107-18. ©2017 AACR.

Selective effect of cytokine-induced killer cells on survival of patients with early-stage melanoma

Adoptive immunotherapy using cytokine-induced killer (CIK) cells has shown potential antitumor ability against several kinds of cancers, including melanoma. However, little is known about the achievable outcome of CIK cells in melanoma patients at different pathological stages. Here we recruited 55 patients treated with conventional therapy plus CIK cells as the CIK group, and 49 patients treated with conventional therapy alone as the control group. The pathological characteristics were comparable between two groups, with a follow-up period up to 40 months. Survival data and immune responses were evaluated after CIK cell treatment. In this study, CIK cells were successfully generated from peripheral blood of melanoma patients after in vitro culture for 14 days. The cultured CIK cells not only produced high levels of pro-inflammatory cytokines upon in vitro stimulation but also efficiently killed human melanoma cell lines. No serious side events were observed in all patients treated with CIK cells. Furthermore, infusions of CIK cells improved the quality of life in some patients, including advanced cases. More importantly, the CIK group exhibited better survival rates compared to the control group among early-stage melanoma patients, in consistent with the increased frequency of peripheral CD4+ T cells. However, the patients with advanced-stage melanoma did not benefit from the CIK cell therapy in terms of survival rate. In conclusion, CIK cells combined with conventional treatments may prolong the survival of early-stage melanoma patients and improve the quality of life for some advanced cases in a safe way.

Novel strategies of adoptive immunotherapy: How natural killer cells may change the treatment of elderly patients with acute myeloblastic leukemia

Although many attempts have been made to identify novel molecular-targeted therapies for patients with acute myeloid leukemia, their translation into the clinic have had limited impact. In particular, the question of effective and curative treatments for elderly patients, who are not eligible for stem cell transplantation, remains an unmet medical need. To answer this question, a wide range of immunologic therapeutic strategies, mostly T cell based, have been proposed and investigated. At present, however, the clinical results have been largely unsatisfactory. Natural killer cells have recently been used as a means of adoptive immunotherapy with promising clinical results. On the basis of recent clinical reports and moving from the basic immunobiology of natural killer cells, here we discuss some open issues in the clinical translation of natural killer-based adoptive immunotherapy for the management of elderly patients with acute myeloid leukemia.

Repurposing platinum-based chemotherapies for multi-modal treatment of glioblastoma

Glioblastoma (GBM) is a fatal brain cancer for which new treatment options are sorely needed. Platinum-based drugs have been investigated extensively for GBM treatment but few have shown significant efficacy without major central nervous system (CNS) and systemic toxicities. The relative success of platinum drugs for treatment of non-CNS cancers indicates great therapeutic potential when effectively delivered to the tumor region(s). New insights into the broad anticancer effects of platinum drugs, particularly immunomodulatory effects, and innovative delivery strategies that can maximize these multi-modal effects and minimize toxicities may promote the re-purposing of this chemotherapeutic drug class for GBM treatment.

The Role of the Immune System in Ovarian Cancer and Implications on Therapy

Ovarian cancer is the leading cause of death from gynecologic malignancy in the United States. While the treatment options have improved with conventional cytotoxic chemotherapy and advanced surgical techniques, disease recurrence is common and fatal in nearly all cases. Current evidence suggests that the immune system and its ability to recognize and eliminate microscopic disease is paramount in preventing recurrence. The goal of immunotherapy is to balance the activation of the immune system against cancer while preventing the potential for tremendous toxicity elicited by immune modulation. In this paper we will review the role of immune system in disease pathogenesis and different immunotherapies available for the treatment of ovarian cancer as well as current ongoing studies and potential future directions.