MTP-PE in liposomes as a biological response modifier in the treatment of cancer: Current status

MTP-PE in liposomes is a BRM which can be given relatively safely to patients with cancer. The maximum tolerated dose appears to be higher than the optimal dose inducing immunomodulatory effects such as cytokine induction and monocyte/macrophage activation. The most consistently induced cytokines measured in the plasma of patients a few hours after MTP-PE are TNF and IL-6. Indirect evidence supports the assumption that increased levels of TNF and IL-6 are signs of macrophage activation occurringin situ in tissues taking up liposomal MTP-PE shortly after injection. These tissues are mainly lungs, liver and spleen, as shown in 4 patients injected with radiolabelled liposomes containing MTP-PE. Assuming that activated monocytes and macrophages cannot eliminate gross tumor load, the main targets for MTP-PE are micrometastases after removal of the primary tumor. Thus, adjuvant treatment using liposomal MTP-PE in combination with chemotherapy is a major goal for the future.     

Pharmacokinetics and immunomodulatory effects on monocytes during prolonged therapy with liposomal muramyltripeptide

The macrophage activator muramyl tripeptide-phosphatidyl ethanolamine (MTP-PE) was infused in liposomal form in 14 metastatic cancer patients (4 mg i.v. during 30 min twice weekly for 12 weeks). Clinical, pharmacokinetic and immunological parameters were studied before and 0.5, 2, 4, 24 and 72h after start of drug infusion in week 1, 4, 8 and 12. No tumor regressions were seen. Tumors progressed in 11 patients, in 4 of them within 2 months; 3 patients had stable disease. The intensity and frequency of side effects (fever and nausea) diminished from week 1 to 12. The rate of disappearance of total and free MTP-PE from blood was rapid and mean serum concentration-time curves remained unchanged throughout 12 study weeks. MTP-PE caused a marked increase of serum TNFa, IL-1 receptor antagonist (IL-1ra) and IL-6 in week 1, but not thereafter. In contrast, MTP-PE caused a persistent, 2-fold increase in serum neopterin and young forms of granulocytes (bands) during week 1 to 12. Before therapy, monocyte tumor cytotoxicity and in-vitro monocyte derived TNFa, IL-1 and IL-6 production were low in 9 patients (group L, <15%) and high in 5 patients (group H, >40%). Monocyte cytotoxicity and in-vitro cytokine production was transiently enhanced in week 1 in group L, it declined under therapy in group H. In conclusion, MTP-PE induced marked initial immunomodulation; the extent of the ex vivo monocyte cytokine and tumor cytotoxic response was dependent on pretherapy cell activity. A decrease of the cytokine and IL-1ra response during prolonged therapy contrasted with a persistent increase of neopterin and juvenile blood granulocytes. The long lasting biologic effects may be relevant to direct future clinical studies with liposomal MTP-PE in an adjuvant setting.Abbreviations MTP-PE muramyl tripeptide-phosphatidyl ethanolamine - IL-1ra IL1 receptor antagonist - TNFa tumor necrosis factor alpha - IL-1 interleukin-1 beta - IL-6 interleukin 6     

The therapeutic effect of OK-432-combined adoptive immunotherapy against liver metastases from gastric or colorectal cancers

Twenty-four patients with liver metastases from gastric or colorectal cancer were treated with OK-432-combined adoptive immunotherapy (AIT). Lymphocytes isolated from regional lymph nodes or peripheral blood were cultured with medium containing T cell growth factor and sonicated tumor extract antigen (SE-Ag) for 9–13 days. The cultured lymphocytes were transferred mainly through the hepatic artery after the administration of OK-432, a streptococcal preparation. Sixteen of the 24 patients received a low dose of anti-cancer agents between the OK-432 injection and cell transfer. When cultured without SE-Ag, regional lymph node lymphocytes (RLNL) showed significantly (P<0.05) higher cytotoxic activity against autologous tumor cells and, on the contrary, lower cytotoxic activity against K562 than peripheral blood lymphocytes (PBL). When cultured with SE-Ag, cytotoxicity of RLNL against autologous tumor cells was nearly equivalent to that of PBL. The blastogenesis of fresh PBL to SE-Ag was significantly (P<0.05) augmented after the OK-432-combined AIT. Two patients showed complete response and 4 patients showed partial response among 19 patients who had evaluable lesions. Five patients whose liver metastases were resected were treated with OK-432-combined AIT as an adjuvant therapy. To date they are alive without recurrence in the liver.Abbreviations AIT adoptive immunotherapy - RLNL regional lymph node lymphocytes - SE-Ag sonicated tumor extract antigen     

Effect of liposomal muramyl tripeptide phosphatidylethanolamine and indomethacin on hematopoietic recovery in irradiated mice

The effects of liposomal muramyl tripeptide phosphatidylethanolamine (MTP-PE/MLV, radioprotective immunomodulator; 10 mg/kg) and indomethacin (INDO, inhibitor of prostaglandin production; 2 mg/kg) on post-irradiation recovery of hematopoietic functions in mice were investigated. Two agents with distinct radioprotective mechanisms were administered alone or in combination 24 h and 3 h before exposure to 7 Gy (60)Co radiation. In the post-irradiation period (3-14 days) combined pre-treatment of mice accelerated recovery of bone marrow cellularity, weight of spleen and myelopoietic and erythropoietic activity in both hematopoietic organs, compared to treatment with MTP-PE/MLV or indomethacin alone. In the peripheral blood, improved radioprotective effects of combined drug administration were found in the recovery of reticulocytes and platelet count. No further significant differences in the recovery of leukocyte count were observed in the examined groups until post-irradiation day 14. Within the first 3-6 post-irradiation days, the bone marrow and peripheral blood smears of mice pre-treated with indomethacin alone or its combination with MTP-PE/MLV more frequently featured blast cells and large cells with abundant cytoplasm which could be considered the hematopoietic stem cells.     

Augmentation of NK cell activity in tissue specific sites by liposomes incorporating MTP-PE

Liposomes incorporating a variety of immunomodulators have been shown to activate macrophages and monocytes for tumoricidal activity both in vivo and in vitro. We report that in addition to the activation of macrophages, the i.v. injection of liposomes (multilamellar vesicles) that have encapsulated muramyl tripeptide-phosphatidylethanolamine (MTP-PE) could also augment interstitial natural killer (NK) cell activity in the lung and the liver. In contrast, liposomes incorporating MTP-PE were unable to augment NK cell activity in the spleen, peripheral blood, or peritoneal cavity (after i.p. injection). In addition, liposomes did not augment splenic NK cell activity in vitro. This suggests that the augmentation of NK cell activity in the lungs and liver was not due to direct effects of the liposomes but may have been a secondary effect mediated by a monokine. The augmentation of pulmonary NK cell activity was paralleled by the nonspecific immunoprophylaxis of experimental pulmonary metastases. The augmented NK cell activity, as well as the enhanced nonspecific immunoprophylactic activity, was reduced by pretreatment of the mice with anti-asialo GM1 antiserum. Thus, the augmentation of organ-associated NK cell activity by liposomes incorporating MTP/PE plays a major role in the host's increased resistance to the formation of experimental metastases.     

Systemic Activation of Macrophages by Liposomes Containing Muramyltripeptide Phosphatidylethanolamine for therapy of Cancer Metastasis

Abstract

The heterogeneous response of metastases to conventional therapy is a major cause of failure in cancer treatment. Evidence that activated macrophages can recognize and destroy neoplastic cells in vitro without regard to their phenotypic diversity has stimulated efforts to develop effective approaches to the activation of macrophages in situ. Systemic administration of liposomes containing immunomodulators activates macrophages in situ and augments host destruction of spontaneous metastases.

Liposomes are a useful carrier system for the transport of agents to phagocytic cells in vivo. Once in the circulation, liposomes are cleared by phagocytic cells, and this passive localization provides an effective mechanism for targeting liposome-entrapped materials, such as muramyltripeptide phosphatidylethanolamine (MTP-PE), to macrophages.

Macrophage destruction of metastases in vivo is significant, provided that the total tumor burden at start of treatment is minimal. For this reason, we advocate using chemotherapy or radiotherapy first to reduce the tumor burden in patients with metastases. Tumoricidal macrophages that can differentiate neoplastic from bystander nonneoplastic cells are then used to destroy the few tumor cells that escape destruction by conventional therapeutic methods.     

Hepatic artery ligation in treatment of carcinoid syndrome.

Summary: In a patient with malignant carcinoid syndrome with metastasis to the liver, cardiac lesions, pulmonary hypertension, pellagra-like skin lesions and depression developed. Her disability progressed despite medical therapy and two courses of chemotherapy. The primary tumour had been resected but the metastatic mass in the liver could not be resected because of its anatomic position. The dramatic improvement after hepatic artery ligation was correlated with urinary 5-hydroxyindole acetic acid excretion.     

Optimization and limitations of systemic treatment of murine melanoma metastases with liposomes containing muramyl tripeptide phosphatidylethanolamine

Summary The purpose of these studies was to determine the optimal conditions and limitations for the eradication of spontaneous melanoma metastases by the systemic administration of liposomes containing MTP-PE. Mice whose primary melanoma had been excised were given i.v. injections of liposomes at various schedules. Optimal treatment was achieved by twice weekly administration for 4 weeks (eight i.v. injections). Bioassays failed to reveal the presence of melanoma cells in lungs of mice surviving to day 250 of the experiment. The success of liposome treatment of metastases diminished when the first i. v. injection of liposomes-MTP-PE commenced on day 10 after surgical excision of the local melanoma, as compared with day 3 or day 7 after surgery. We conclude that the major limitation for macrophage-mediated destruction of metastases is the number of tumor cells in the lesions. Because of this limitation, it is unlikely that the systemic activation of macrophages could be used as a single modality for treatment of advanced metastases.     

Use of human leukocyte antigen-mismatched allogeneic lymphokine-activated killer cells and interleukin-2 in the adoptive immunotherapy of patients with malignancies.

Clinical effects and side effects were investigated in the adoptive immunotherapy of patients bearing malignant diseases using human leukocyte antigen (HLA)-mismatched allogeneic lymphokine-activated killer (LAK) cells. Allogeneic LAK cells were induced from peripheral blood lymphocytes (PBL) of healthy donors with the same blood types as those of patients. Recently we succeeded in increasing the proliferation rate and enhancing the cytotoxic activity of LAK cells by means of initial stimulation with pokeweed mitogen (PWM, PWM-LAK cells). Five of 12 patients applied in the adoptive immunotherapy showed clinical effects such as partial or complete regression of pulmonary metastases and pleural effusion. All pulmonary metastatic lesions were eliminated in one case by this adoptive immunotherapy combined with chemotherapy. Toxic effects were chillness, fever and general fatigue which were reversible, and no allergic side effects occurred even though allogeneic LAK cells were injected frequently. In the patients who received more than 10(11) of allogeneic LAK cells, anti-HLA class I antibodies appeared without any evidence of autoantibody. However, immunological side effects were never experienced after injection of allogeneic LAK cells even when the anti-HLA class I antibodies existed in the patients; this phenomenon suggests the safety of the adoptive immunotherapy using allogeneic LAK cells. Taken together, allogeneic LAK cells could be considered as alternative therapy for patients with malignancies who could not supply sufficient materials of autologous LAK cells. Recently, LAK cells, particularly PWM-LAK cells were found to obtain significantly potent and prompt lectin-dependent cell-mediated cytotoxicity (LDCC). All tumor cells confluent in microtest plate well could be annihilated by PWM-LAK cells plus PWM less than 8 hours. New immunotherapy using PWM-LAK cells or lectin-stimulated LAK cells with PWM or other lectins is discussed.     

A Pilot Study of Cryochemotherapy for Hepatic Metastases from Colorectal Cancer

Cryosurgery of hepatic metastases from colorectal carcinoma is a form of local therapy for unresectable disease. After curative resection, failures occur in the liver, and at extrahepatic sites. This pilot study evaluated the toxicity and tolerance to cryotherapy and intraoperative chemotherapy for unresectable hepatic metastases from colorectal cancer. If after exploratory celiotomy for potential curative resection of hepatic metastases the patient was deemed unresectable because of location and/or number of lesions, cryosurgery and intraoperative chemotherapy with systemic 5-fluorouracil 600 mg/m²and leucovorin 500 mg/m²was performed. Four patients were treated with cryochemotherapy. All patients developed toxicity. Two patients developed grade III leukopenia on Postoperative Days 2 and 12, and grades II and III diarrhea on Postoperative Days 5 and 7, respectively. Grade III hyperbilirubinemia and thrombocytopenia occurred in one patient on Postoperative Days 3 and 7. Acute respiratory distress syndrome, postoperative ileus, and grade II mucositis occurred in one patient each. All patients had delays and dose reductions on their subsequent chemotherapy treatments secondary to toxicity. Two patients had disease progression, one had stable disease, and one is “disease free.” Combining the tumoricidal effects of chemotherapy and cryosurgery is in theory a good concept. However, the toxicity of 5-FU and leucovorin is enhanced by this approach.     

Immunotherapy of osteogenic sarcoma with transfer factor

Summary Fifteen patients with osteogenic sarcoma were treated with transfer factor derived from leukocytes of their household contacts. Eight of the fifteen patients were tumor-bearing, and transfer factor therapy was correlated with increased cell-mediated immunity in peripheral blood lymphocytes and with lymphocytic infiltrates into the tumors. There was no marked increased in survival time as compared with historical controls, but this therapy did not accelerate the disease, and there were no untoward side effects.Seven of the fifteen patients were disease-free when transfer therapy was initiated shortly after surgical removal of the primary tumor (five patients) or solitary pulmonary metastases (two patients). These patients received transfer factor injections every 2 weeks for 1–2 years. Six of the seven patients are disease-free 62–82 months after surgery. Compared with probabilities of 5-year survival computed from historical controls, this is significant at P<0.008. Abbreviations used in this paper are: CI, cytotoxicity index; GCT, giant cell tumor of bone; HHC, household contacts; HHC_os, household contacts of patients with osteogenic sarcoma; MIC, mononuclear inflammatory cell; TFCI, transfer factor cytotoxicity index; TSTF, tumor-specific transfer factor.     

Use of human leukocyte antigen-mismatched allogeneic lymphokine-activated killer cells and interleukin-2 in the adoptive immunotherapy of patients with malignancies

Clinical effects and side effects were studied in the adoptive immunotherapy of patients bearing malignant diseases using human leukocyte antigen (HLA)-mismatched allogeneic lymphokine-activated killer (LAK) cells. Allogeneic LAK cells were induced from peripheral blood lymphocytes (PBL) of normal donors by means of initial stimulation with pokeweed mitogen (PWM). Six of 15 patients applied in the adoptive immunotherapy showed clinical effects such as partial or complete regression of pulmonary metastasis, pleural effusion and primary tumor. All pulmonary metastatic lesions were eliminated in one case by this adoptive immunotherapy combined with chemotherapy. Generally toxic effects were chillness, fever and general fatigue which were reversible, and no allergic side effects occurred even though allogeneic LAK cells were injected frequently except one patient who showed preshock like symptom accompanied with leukocytopenia and continuous hypotension immediately after infusion but was finally rescued. In the patients who received more than 10¹¹ of allogeneic LAK cells, anti-HLA class I antibodies appeared without any evidence of autoantibody. However, immunological side effects were never experienced after injection of allogeneic LAK cells even when the anti-HLA class I antibodies appeared in the patients. Taken together, allogeneic LAK cells could be considered as alternative therapy for patients with malignancies who could not supply sufficient materials of autologous LAK cells.Abbreviations PWM pokeweed mitogen - LAK lymphokine-activated killer - IL-2 interleukin 2 - PEL peripheral blood lymphocytes - TIL tumor-infiltrating lymphocytes - GVHD graft-versus-host disease - HLA human leukocyte antigen     

Varicella Pneumonia—A Report of Twenty Cases,With Postmortem Examination in Six

Twenty cases of primary varicella pneumonia, 16 in adults and four in children, were studied. Two adults and four children died, two of the latter with complicating bacterial infections. In two patients the primary cause of death was severe alveolar-capillary block. Staphylococcal septicemia, midbrain hemorrhage and meningoencephalitis were primarily responsible for death in other patients.Radiologically, the lungs showed diffuse, poorly marginated, nodular lesions, often peribronchial in location, more easily defined in the thinner peripheral lung fields, with an alveolar acinar pattern, tending to coalesce in the hilar and perihilar regions. Pathologically, the cutaneous varicella lesions were matched by similar lesions regularly found in the lungs and pleura, as well as the peritoneum and the liver. The pulmonary nodular lesions corresponded to alveoli, filled with precipitated protein and active inflammatory cellular material, surrounding the bronchioles, which themselves were often involved, and these in turn were surrounded by areas of normally aerated alveoli.Eleven moderately to severely ill patients were treated with antibiotics, six moderately to extremely ill were treated with antibiotics and adrenal cortical steroids. There was no evidence of significant change in the course of the disease resulting from use of steroid therapy.     

Stimulant effect of the immunomodulator MTP-PE on proliferation of monocytic cells in the guinea pig

The effect of a single subcutaneous injection of various doses of the lipophilic muramyl tripeptide MTP-PE on cell proliferation was investigated in autoradiographs of histological sections of various organs of the guinea pig. The animals either received first MTP-PE in saline and then one 3H-thymidine pulse 1 h prior to sacrifice, or they were prelabeled with 3H-thymidine and then received MTP-PE. The number of proliferating cells increased up to between two and fivefold (marginally after 0.3 mg/kg and maximally after 30 mg/kg MTP-PE), but differed in the various organs. In addition, the time of the maximal increase varied between 5 h and 72 h after MTP-PE treatment and also depended on the organ. The majority of proliferating cells were of the monocyte lineage seen in conjunction with the vascular system. They were apparently promonocytes still capable of proliferation. Evidence for this conclusion is derived from (i) the distribution of 1 h-pulse-labeled cells in the various organ compartments in relation to the stimulated proliferation of the bone-marrow cells, and (ii) the distribution of the prelabeled, mainly bone-marrow derived cells, to the various organs. The augmented proliferation of the monocyte lineage is preceded by a dose-dependent, short-lasting increase in the proliferation of some epithelia and also by an increase in body temperature and a transient change in plasma proteins. These effects are part of a limited inflammatory reaction and may contribute to the immunostimulation.     

Short-term kinetics of tumor antigen expression in response to vaccination

The melanoma patient's immune response to tumor has been extensively studied. Yet, the frequently observed coexistence of tumor-associated Ag (TAA)-specific T cells with their target cells in vivo remains unexplained. Loss of TAA expression might contribute to this paradox. We studied TAA expression in metastases by obtaining fine-needle aspirations from 52 tumor lesions in 30 patients with melanoma before and soon after immunotherapy. Limitations due to low amounts of starting material were overcome with a high fidelity antisense RNA amplification method. TAA expression was measured by quantitative real-time PCR of anti-sense RNA. Decrease in gp100/Pmel-17 TAA preceded tumor disappearance in several instances and could be best explained by immune selection because most patients had received gp100/Pmel-17-specific vaccination. Conversely, immune selection was absent in nonregressing lesions. These observations suggest that vaccination, when successful, triggers a broad inflammatory reaction that can lead to tumor destruction despite immune selection. Additionally, lack of clinical response might be attributed to lack of this initiating event rather than immune escape. This study provides an insight into the natural history of tumors and defines a strategy for the characterization of gene expression in tumors during therapy.     

Liposomal muramyl dipeptide therapy of experimental M5076 liver metastases in mice

Summary The effectiveness ofN-acetylmuramyl-l-alanyl-d-isoglutamine (MDP) or of liposomes containing a lipophilic MDP derivative, MDP-glyceroyldipalmitate MDP-GDP in inhibiting the growth of M5076 reticulum cell sarcoma liver metastases in C57BL/6 mice has been determined. MDP (100 µg) or liposomal MDP-GDP (2.5 µmol containing 1 µg) were equally effective in inhibiting liver metastatic growth when given as a single treatment 3 days before tumor cell injection. Therapeutic treatment, initiated 3 days after tumor cell injection and continued for a period of 2 weeks, failed to inhibit metastatic growth. Activation of thioglycollate-elicited peritoneal macrophages or Kupffer cells in vitro with MDP or liposomal MDP-GDP resulted in the expression of tumoricidal activity against M5076 tumor cells. Adoptive cellular therapy with four injections of 2 × 10⁶ macrophages was ineffective: activation of the macrophages with either MDP or liposomal MDP-GDP prior to injection was effective in inhibiting liver metastatic growth. Incorporation of the macrophage toxin dichlorodimethylene diphosphonate within liposomes containing MDP-GDP abolished the ability of such liposomes to induce macrophage or Kupffer cell tumoricidal activity in vitro as well as the antitumor activity when administered 3 days before tumor cell challenge.     

Role of interleukin-23 circulating levels increase in resected colorectal cancer before and after chemotherapy: preliminary data and future perspectives

Expression of IL‐23, a heterodimeric cytokine involved in the induction of Th17 cells, is increased in human tumors. Although the endogenous IL‐23 expression has been reported to promote tumor development and growth, the studies using local and systemic administration of IL‐23 have shown that its application at the excessive amount induces antitumor immune responses. IL‐23 is, today, considered the key driver of intestinal inflammation and its role in inflammatory responses is tissue‐specific. The aim of this study was to investigate the role of circulating levels of IL‐23 in patients with resected colorectal cancer (CRC) before and after chemotherapy, respect to healthy controls. Twenty‐five patients were enrolled between June 2007 and January 2009, and followed through 2010. All patients underwent chemotherapy, mostly FOLFOX4. Twenty‐sex and age‐matched healthy donors were recruited as controls. IL‐23 serum concentrations, measured by a quantitative enzyme immunoassay technique, were significantly higher in patients with resected CRC (26.02 ± 28.63 pg/ml versus 7.1 ± 6.4 pg/ml, P < 0.001) and after chemotherapy respect to controls (21.74 ± 23.82 pg/ml versus 7.17 ± 6.43 pg/ml, P < 0.001). An increase was documented also before chemotherapy (26.02 ± 28.63 pg/ml versus 21.74 ± 23.82 pg/ml, P = 0.7) but not statistically significant. This work investigated, for the first time, the role of IL‐23 in CRC resection and chemotherapy, showing no correlation with the severity of disease, tumor removal, and chemotherapeutic treatment. However, other works are needed to better clarify if IL‐23 could be considered a key‐molecule in human CRC and a target for tumor treatment. J. Cell. Physiol. 226: 3032–3034, 2011. © 2011 Wiley‐Liss, Inc.     

波生坦治疗特发性肺动脉高压的疗效与安全性观察

目的:探讨波生坦治疗特发性肺动脉高压(IPAH)的疗效与安全性。方法:16例IPAH患者予波生坦口服治疗20周,比较治疗前后患者心功能、6分钟步行距离(6MWD)、肺动脉压力以及血常规、肝肾功能变化。结果:患者心功能由治疗前Ⅲ级13例、Ⅳ级3例变为Ⅱ级14例、Ⅲ级2例。6MWD较治疗前明显延长(P<0.01),肺动脉收缩压、肺动脉平均压及肺动脉舒张压均较治疗前显著降低(P<0.01),患者血常规、肝肾功能较治疗前无明显变化。结论:口服波生坦治疗IPAH可明显改善患者的临床症状与血流动力学指标,安全性好。     

Biomarkers of Residual Disease,Disseminated Tumor Cells,and Metastases in the MMTV-PyMT Breast Cancer Model

Cancer metastases arise in part from disseminated tumor cells originating from the primary tumor and from residual disease persisting after therapy. The identification of biomarkers on micro-metastases, disseminated tumors, and residual disease may yield novel tools for early detection and treatment of these disease states prior to their development into metastases and recurrent tumors. Here we describe the molecular profiling of disseminated tumor cells in lungs, lung metastases, and residual tumor cells in the MMTV-PyMT breast cancer model. MMTV-PyMT mice were bred with actin-GFP mice, and focal hyperplastic lesions from pubertal MMTV-PyMT;actin-GFP mice were orthotopically transplanted into FVB/n mice to track single tumor foci. Tumor-bearing mice were treated with TAC chemotherapy (docetaxel, doxorubicin, cyclophosphamide), and residual and relapsed tumor cells were sorted and profiled by mRNA microarray analysis. Data analysis revealed enrichment of the Jak/Stat pathway, Notch pathway, and epigenetic regulators in residual tumors. Stat1 was significantly up-regulated in a DNA-damage-resistant population of residual tumor cells, and a pre-existing Stat1 sub-population was identified in untreated tumors. Tumor cells from adenomas, carcinomas, lung disseminated tumor cells, and lung metastases were also sorted from MMTV-PyMT transplant mice and profiled by mRNA microarray. Whereas disseminated tumors cells appeared similar to carcinoma cells at the mRNA level, lung metastases were genotypically very different from disseminated cells and primary tumors. Lung metastases were enriched for a number of chromatin-modifying genes and stem cell-associated genes. Histone analysis of H3K4 and H3K9 suggested that lung metastases had been reprogrammed during malignant progression. These data identify novel biomarkers of residual tumor cells and disseminated tumor cells and implicate pathways that may mediate metastasis formation and tumor relapse after therapy.