Tumor‐reactive CD8+ T‐cell responses after vaccination with NY‐ESO‐1 peptide,CpG 7909 and Montanide® ISA‐51: association with survival

Peptide‐based vaccines have led to the induction of antigen‐specific CD8⁺ T‐cell responses in patients with NY‐ESO‐1 positive cancers. However, vaccine‐induced T‐cell responses did not generally correlate with improved survival. Therefore, we tested whether a synthetic CpG 7909 ODN (deoxycytidyl‐deoxyguanosin oligodeoxy‐nucleotides) mixed with NY‐ESO‐1 peptide p157‐165 and incomplete Freund's adjuvants (Montanide® ISA‐51) led to enhanced NY‐ESO‐1 antigen‐specific CD8⁺ immune responses in patients with NY‐ESO‐1 or LAGE‐1 expressing tumors. Of 14 HLA‐A2+ patients enrolled in the study, 5 patients withdrew prematurely because of progressive disease and 9 patients completed 1 cycle of immunization. Nine of 14 patients developed measurable and sustained antigen‐specific CD8⁺ T‐cell responses: Four had detectable CD8+ T‐cells against NY‐ESO‐1 after only 2 vaccinations, whereas 5 patients showed a late‐onset but durable induction of NY‐ESO‐1 p157‐165 specific T‐cell response during continued vaccination after 4 months. In 6 patients, vaccine‐induced antigen‐specific T‐cells became detectable ex vivo and reached frequencies of up to 0.16 % of all circulating CD8⁺ T‐cells. Postvaccine T‐cell clones were shown to recognize and lyse NY‐ESO‐1 expressing tumor cell lines in vitro. In 6 of 9 patients developing NY‐ESO‐1‐specific immune responses, a favorable clinical outcome with overall survival times of 43+, 42+, 42+, 39+, 36+ and 27+ months, respectively, was observed.     

Targeting breast cancer‐initiating/stem cells with melanoma differentiation‐associated gene‐7/interleukin‐24

Melanoma differentiation‐associated gene‐7/interleukin‐24 (mda‐7/IL‐24) displays a broad range of antitumor properties including cancer‐specific induction of apoptosis, inhibition of tumor angiogenesis and modulation of antitumor immune responses. In our study, we elucidated the role of MDA‐7/IL‐24 in inhibiting growth of breast cancer‐initiating/stem cells. Ad.mda‐7 infection decreased proliferation of breast cancer‐initiating/stem cells without affecting normal breast stem cells. Ad.mda‐7 induced apoptosis and endoplasmic reticulum stress in breast cancer‐initiating/stem cells similar to unsorted breast cancer cells and inhibited the self‐renewal property of breast cancer‐initiating/stem cells by suppressing Wnt/β‐catenin signaling. Prevention of inhibition of Wnt signaling by LiCl increased cell survival upon Ad.mda‐7 treatment, suggesting that Wnt signaling inhibition might play a key role in MDA‐7/IL‐24‐mediated death of breast cancer‐initiating/stem cells. In a nude mouse subcutaneous xenograft model, Ad.mda‐7 injection profoundly inhibited growth of tumors generated from breast cancer‐initiating/stem cells and also exerted a potent “bystander” activity inhibiting growth of distant uninjected tumors. Further studies revealed that tumor growth inhibition by Ad.mda‐7 was associated with a decrease in proliferation and angiogenesis, two intrinsic features of MDA‐7/IL‐24, and a reduction in vivo in the percentage of breast cancer‐initiating/stem cells. Our findings demonstrate that MDA‐7/IL‐24 is not only nontoxic to normal cells and normal stem cells but also can kill both unsorted cancer cells and enriched populations of cancer‐initiating/stem cells, providing further documentation that MDA‐7/IL‐24 might be a safe and effective way to eradicate cancers and also potentially establish disease‐free survival.     

Thromboprophylaxis with low‐molecular‐weight heparin in medical patients with cancer

Venous thromboembolism (VTE) is a frequent complication of cancer and cancer treatment and is associated with multiple clinical consequences, including recurrent VTE, bleeding, and an increase in the risk of death. Although the risks associated with VTE have been well recognized in surgical cancer patients, there is also considerable and increasing risk in medical cancer patients. VTE risk factors in medical cancer patients include the type and stage of cancer, major comorbid illnesses, current hospitalization, active chemotherapy, hormone therapy, and antiangiogenic agents. Low‐molecular‐weight heparins (LMWHs) are recommended commonly for the prevention of VTE in hospitalized cancer patients and in higher risk ambulatory cancer patients because of their favorable risk‐to‐benefit profile. These agents have demonstrated effectiveness in both the primary and secondary prevention of VTE in medical cancer patients. Extended‐duration anticoagulant therapy is often recommended to reduce the risk of VTE recurrence in patients with cancer. LMWHs are often used for long‐term prophylaxis because of a reduced need for coagulation monitoring, few major bleeding episodes, and once‐daily dosing. Despite clinical and practical benefits, a substantial proportion of medical cancer patients do not receive VTE prophylaxis. To improve the appropriate prevention and treatment of VTE in cancer patients, guidelines have been published recently by the American Society of Clinical Oncology and the National Comprehensive Cancer Network. Widespread dissemination and application of these guidelines are encouraged to improve the appropriate use of these agents and to improve clinical outcomes in medical cancer patients at risk for VTE and its complications. Cancer 2009. © 2009 American Cancer Society.     

Long‐term outcome of patients with solitary plasmacytoma treated with radiotherapy: A population‐based,single‐center study with median follow‐up of 13.7 years

In this single‐center, population‐based, and retrospective study, we analyzed the outcome of 49 patients with solitary bone plasmacytoma (SBP) and 28 patients with solitary extramedullary plasmacytoma (SEP), all treated with radiotherapy. Laminectomy was performed in 18/30 SBP patients with vertebral involvement and tumour resection in 10 SEP patients. Overall survival and cause of death for each patient were compared to 5 sex‐, age‐, and residency‐matched individuals from the normal population. Response (complete and partial) was achieved in 94% of SBP and 96% of SEP patients. Relapse rates were higher in SBP (65%) compared to patients with SEP (18%) (P < .01). Only one in‐field relapse was identified for the whole series. Ten‐ and 15‐year overall survival, progression free survival (PFS) and multiple myeloma free survival (MMFS) for patients with SBP were 60%/41%, 25%/17%, and 33%/33%. Corresponding values for patients with SEP were 67%/54%, 57%/44%, and 91%/91%. SBP patients had significantly shorter PFS and MMFS compared to SEP patients (P < .01 for both). Only two of the SEP patients developed multiple myeloma and no patient in the whole series progressed to multiple myeloma later than 10 years after diagnosis. Unlike for SEP, the major cause of death among SBP patients was multiple myeloma (49%). Compared to matched normal population, no increased risk of death from secondary malignancies or cardiovascular disease was observed. Positive predictors in SBP patients were for overall survival age <60 years, combined laminectomy and radiotherapy and radiotherapy dose >40 gray, for PFS tumour size <6 cm and combined laminectomy and radiotherapy and for MMFS tumour size <6 cm. Radiotherapy confers excellent local control in both SEP and SBP patients; however, the challenge is to prevent development of multiple myeloma in patients with SBP.     

Non‐vascular intervention with real‐time CT fluoroscopy

The emerging technology of CT fluoroscopy (CTF) represents the first opportunity for real‐time CT guidance in non‐vascular intervention. As with any new technology, its efficacy requires validation before widespread application can be advocated. A review of our initial experience is presented with particular attention to room, procedure and fluoroscopy time savings, complication rates and dosimetry. Computed tomography fluoroscopy is useful for pulmonary, pelvic, retroperitoneal and other deep organ lesions that are not easily accessible by other modalities. Computed tomography fluoroscopy decreases procedure time by at least a factor of 2 compared with conventional CT (C‐CT) guidance, resulting in improved throughput in a busy interventional CT department. Accurate targeting of small lesions, previously considered inaccessible, can also be achieved with CTF. Exposure to the physician’s hands can be reduced to a level that is acceptable to the International Commission on Radiological Protection guidelines.     

NY‐ESO‐1 specific antibody and cellular responses in melanoma patients primed with NY‐ESO‐1 protein in ISCOMATRIX and boosted with recombinant NY‐ESO‐1 fowlpox virus

Vaccination strategies based on repeated injections of NY‐ESO‐1 protein formulated in ISCOMATRIX particles (NY‐ESO‐1 ISCOMATRIX) have shown to elicit combined NY‐ESO‐1 specific antibody and T cell responses. However, it remains unclear whether heterologous prime‐boost strategies based on the combination with NY‐ESO‐1 ISCOMATRIX with different NY‐ESO‐1 boosting reagents could be used to increase NY‐ESO‐1 CD8⁺ or CD4⁺ T cell responses. To address this question, we carried out a randomized clinical trial in 39 high‐risk, resected melanoma patients vaccinated with NY‐ESO‐1 ISCOMATRIX, and then boosted with repeated injections of either recombinant fowlpox virus encoding full length NY‐ESO‐1 (rF‐NY‐ESO‐1) (Arm A) or NY‐ESO‐1 ISCOMATRIX alone (Arm B). We have comprehensively analyzed NY‐ESO‐1 specific T cells and B cells response in all patients before and after vaccination for a total of seven time points per patient. NY‐ESO‐1 ISCOMATRIX alone elicited a strong NY‐ESO‐1 specific CD4⁺ T cell and antibody response, which was maintained by both regiments at similar levels. However, CD8⁺ T cell responses were significantly boosted in 3 out of 18 patients in Arm A after the first rF‐NY‐ESO‐1 injection and such responses were maintained until the end of the trial, while no patients in Arm B showed similar CD8⁺ T cell responses. In addition, our results clearly identified immunodominant regions in the NY‐ESO‐1 protein: NY‐ESO‐1_79–102 and NY‐ESO‐1_115–138 for CD4+ T cells and NY‐ESO‐1_85–108 for CD8+ T cells in a large proportion of vaccinated patients. These regions of NY‐ESO‐1 protein should be considered in future clinical trials as immunodominant epitopes.     

Enhanced tumorigenesis of forestomach tumors induced by N‐Methyl‐N′‐nitro‐N‐nitrosoguanidine in rats with hypoinsulinemic diabetes

Hyperinsulinemia and hyperglycemia in prediabetic and diabetic patients are thought to increase the risk of developing neoplasms because insulin is a growth factor with pre‐eminent metabolic but also mitogenic effects. To determine the effect of hypoinsulinemic diabetic conditions on carcinogenesis, we examined N‐Methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG)‐induced forestomach carcinogenesis in hypoinsulinemic diabetic WBN/Kob rats aged about 45 weeks (DM) compared with non‐diabetic younger WBN/Kob rats (C1), non‐diabetic Wistar rats age‐matched to DM (C2), and non‐diabetic Wistar rats age‐matched to C1 (C3). All rats were treated with MNNG by gavage and were killed at 40 weeks after dosing. Various‐sized tumors were disseminated throughout the forestomach of all rats, and the ratio of the area of tumors to the whole forestomach area was 23.3% in the DM group and was higher than in the C1–3 (4.2–14.3%) groups. The incidence of carcinoma was much higher in the DM group (36.8%) than in the C1–3 (7.1–16.7%) groups, and the incidence of papilloma was also significantly higher in the DM group (84.2%) than in the C1–3 (28.5–50.0%) groups. The average thickness of the squamous epithelium in the non‐neoplastic mucosa was significantly greater in the DM group (50.8 μm) than in the C1–3 (29.6–37.9 μm) groups. Immunohistochemically, the Ki‐67‐positive index in the non‐tumorous mucosa of the DM group (42.0%) was significantly higher than that of the C1–3 groups (18.8–33.3%). These results suggest that prolonged hyperglycemic conditions without hyperinsulinemia enhance tumorigenesis of MNNG‐induced tumors by enhanced proliferative activity of the squamous epithelium in the rat forestomach. (Cancer Sci 2010)     

High‐affinity PD‐1 molecules deliver improved interaction with PD‐L1 and PD‐L2

The inhibitory checkpoint molecule programmed death (PD)‐1 plays a vital role in maintaining immune homeostasis upon binding to its ligands, PD‐L1 and PD‐L2. Several recent studies have demonstrated that soluble PD‐1 (sPD‐1) can block the interaction between membrane PD‐1 and PD‐L1 to enhance the antitumor capability of T cells. However, the affinity of natural sPD‐1 binding to PD‐L1 is too low to permit therapeutic applications. Here, a PD‐1 variant with approximately 3000‐fold and 70‐fold affinity increase to bind PD‐L1 and PD‐L2, respectively, was generated through directed molecular evolution and phage display technology. Structural analysis showed that mutations at amino acid positions 124 and 132 of PD‐1 played major roles in enhancing the affinity of PD‐1 binding to its ligands. The high‐affinity PD‐1 mutant could compete with the binding of antibodies specific to PD‐L1 or PD‐L2 on cancer cells or dendritic cells, and it could enhance the proliferation and IFN‐γ release of activated lymphocytes. These features potentially qualify the high‐affinity PD‐1 variant as a unique candidate for the development of a new class of PD‐1 immune‐checkpoint blockade therapeutics.     

Anti‐Hu‐Associated Autoimmune Limbic Encephalitis in a Patient with PD‐1 Inhibitor‐Responsive Myxoid Chondrosarcoma

Autoimmune encephalitis is an uncommon complication of immune checkpoint inhibitor therapy. This article reports a case of fatal anti‐Hu‐associated autoimmune limbic encephalitis presenting within 8 weeks following anti‐PD1 therapy in a patient with myxoid chondrosarcoma and pre‐existing anti‐Hu antibodies. Although tumor reduction occurred in response to PD‐1 inhibitor therapy, the patient had a rapidly progressive decline in neurologic function despite initial stabilization with immunosuppression. Considering the increasing use of immune checkpoint inhibitors for the treatment of various malignancies, an increase in the occurrence of neurologic adverse events is likely, requiring prompt intervention and enhanced pharmacovigilance in malignancies associated with onconeuronal antibodies.     

Dose‐finding study of 153Sm‐EDTMP in patients with poor‐prognosis osteosarcoma

BACKGROUND:

Samarium‐153 ethylenediaminetetramethylene phosphonic acid (¹⁵³Sm‐EDTMP) has been used to treat patients with high‐risk osteosarcoma. The purpose of the current study was to determine the maximally tolerated dose of ¹⁵³Sm‐EDTMP that permits hematopoietic recovery within 6 weeks.

METHODS:

Patients with recurrent or refractory osteosarcoma with bone metastases were enrolled in this study. Subjects were treated with increasing doses of ¹⁵³Sm‐EDTMP, beginning with 1.0 millicuries (mCi)/kg and followed initially with 40% increment dose level escalations, using a continual reassessment method for dose escalation and de‐escalation with a target dose–limiting toxicity (DLT) rate of 30%. Complete blood counts were monitored weekly, and the primary DLT was defined as failure to achieve an absolute neutrophil count >750/mm³ and a platelet count >75,000/mm³ within 6 weeks of treatment. In addition to assessing toxicity, dosimetry measurements were made to estimate the radiation dose delivered to target lesions.

RESULTS:

The maximally tolerated dose of ¹⁵³Sm‐EDTMP was 44.8 megabecquerel (MBq)/kg (1.21 mCi/kg). DLTs were confined to hematologic toxicities, particularly delayed platelet recovery in 2 patients treated at a dose of 51.8 MBq/kg (1.4 mCi/kg). Grade 2 and 3 pulmonary toxicity (graded according to the National Cancer Institute Common Toxicity Criteria [version 3.0]) as reported in 2 patients (at administered activities of 44.8 MBq/kg and 51.8 MBq/kg) was attributable to progressive pulmonary disease. No other significant nonhematologic toxicities were observed.

CONCLUSIONS:

Patients with osteosarcoma who have previously been heavily treated with chemotherapy can be safely administered ¹⁵³Sm‐EDTMP with rapid hematologic recovery. The data from the current study support the development of a future trial to assess the efficacy of combining targeted radiotherapy with cytotoxic chemotherapy as a treatment option for patients with high‐risk osteosarcoma. Cancer 2009. © 2009 American Cancer Society.     

The clinical value of HPV genotyping in triage of women with high‐risk‐HPV‐positive self‐samples

Cytology alone, or combined with HPV16/18 genotyping, might be an acceptable method for triage in hrHPV‐cervical cancer screening. Previously studied HPV‐genotype based triage algorithms are based on cytology performed without knowledge of hrHPV status. The aim of this study was to explore the value of hrHPV genotyping combined with cytology as triage tool for hrHPV‐positive women. 520 hrHPV‐positive women were included from a randomised controlled self‐sampling trial on screening non‐attendees (PROHTECT‐3B). Eighteen baseline triage strategies were evaluated for cytology and hrHPV genotyping (Roche Cobas 4800) on physician‐sampled triage material. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), referral rate, and number of referrals needed to diagnose (NRND) were calculated for CIN2+ and CIN3+. A triage strategy was considered acceptable if the NPV for CIN3+ was ≥98%, combined with maintenance or improvement of sensitivity and an increase in specificity in reference to the comparator, being cytology with a threshold of atypical cells of undetermined significance (ASC‐US). Three triage strategies met the criteria: HPV16+ and/or ≥LSIL; HPV16+ and/or ≥HSIL; (HPV16+ and/or HPV18+) and/or ≥HSIL. Combining HPV16+ and/or ≥HSIL yielded the highest specificity (74.9%, 95% CI 70.5–78.9), with a sensitivity (94.4%, 95% CI 89.0–97.7) similar to the comparator (93.5%, 95% CI 87.7–97.1), and a decrease in referral rate from 52.2% to 39.5%. In case of prior knowledge of hrHPV presence, triage by cytology testing can be improved by adjusting its threshold, and combining it with HPV16/18 genotyping. These strategies improve the referral rate and specificity for detecting CIN3+ lesions, while maintaining adequate sensitivity.