Fatal Allograft Rejection and Cardiac Allograft Vasculopathy After Treatment With Pembrolizumab for Metastatic Melanoma in a Heart Transplant Recipient: A Case Report.

Checkpoint inhibitors decrease the progression of many cancers. However, the experience in immunosuppressed patients is limited, with reports of possible serious adverse events. We present a heart transplant recipient treated with pembrolizumab for metastatic melanoma who developed fatal rejection. The patient was a 29 year-old man who underwent heart transplantation at the age of 10 years for congenital heart disease. Seventeen years after transplant, he was diagnosed with scalp melanoma pT3a, N2a, M0, Stage IIIA, positive for BRAF V600E mutation treated with excision, which metastasized to his lungs and brain a year later. Dabrafenib and trametinib were started with transient response. Additional options and their risks were discussed, and pembrolizumab was started 4 months later due to the incomplete response to previous therapy. Five days after initiation the patient presented with moderate cellular rejection and possible antibody mediated rejection (ISHLT Grade 2R, pAMR 1H). Pembrolizumab was discontinued, and he was treated with steroids. Seven months later he presented in cardiogenic shock and severe coronary allograft vasculopathy. Biopsy was negative for cellular rejection, but suspicious for antibody mediated rejection (ISHLT Grade 0R, pAMR 1H), and he had a new serum alloantibody. Despite steroids and plasmapheresis he remained in refractory cardiogenic shock and died of cardiac arrest.

Nivolumab and Stereotactic Radiosurgery for Patients With Breast Cancer Brain Metastases: A Nonrandomized, Open-Label Phase 1b Study.

PURPOSE: We hypothesize treatment with nivolumab and stereotactic radiosurgery (SRS) will be feasible and well tolerated, and may improve intracranial tumor control rates compared with SRS alone. METHODS AND MATERIALS: The study was designed as a prospective, single-arm, nonrandomized, open-label, phase 1b trial of nivolumab and SRS among patients with metastatic breast cancer brain metastases. Key eligibility criteria included patients with breast cancer brain metastases of all subtypes, age ≥18, Eastern Cooperative Oncology Group Performance Status ≤2 with ≤10 brain metastases. Treatment was initiated with a dose of nivolumab (480 mg intravenously) that was repeated every 4 weeks. The initial dose of nivolumab was followed 1 week later by SRS. This study is closed to accrual and is registered with ClinicalTrials.gov, NCT03807765. RESULTS: Between February 2019 and July 2020, a total of 12 patients were treated to 17 lesions. No dose limiting toxicities were noted in our patient population. The most common neurologic adverse events included grade 1 to 2 headaches and dizziness occurring in 5 (42%) of patients. Median intracranial control was 6.2 months (95% confidence interval, 3-14 months) with 6- and 12-month control rates of 55% and 22%, respectively. A total of 4 patients had systemic progression during the study. Median time to systemic progression free survival has not been reached with 6- and-12 month rates of 63% and 51%, respectively. CONCLUSIONS: Nivolumab and SRS is a safe and feasible treatment option in breast cancer brain metastases. Preliminary data reveals activity in certain breast cancer patients to study therapy.

Real-world benefit of combination palbociclib and endocrine therapy for metastatic breast cancer and correlation with neutropenia.

BACKGROUND: Combination CDK4/6 inhibitor and endocrine therapy has been shown to significantly improve progression-free survival (PFS) in patients with hormone receptor (HR)-positive, HER2-negative metastatic breast cancer (mBC). The aim of this retrospective study was to evaluate the real-world benefit of first-line combination therapy in this cohort and to correlate treatment efficacy with neutropenia, a common toxicity of CDK4/6 inhibitors. METHODS: This study included HR-positive, HER2-negative advanced or mBC patients who were treated with palbociclib plus endocrine therapy, mainly letrozole, between 1 January 2015 and 1 March 2018. Progression-free survival (PFS) was determined using Kaplan-Meier analysis. The predictive value of absolute neutrophil count (ANC) and neutrophil-to-lymphocyte ratio (NLR) for PFS were explored using Cox regression models. Both ANC and NLR were used as a time-dependent variable. RESULTS: In total, 165 patients were included with median PFS of 24.19 months (95% CI 18.93-NR). Median PFS for patients with bone-only metastases (n = 54) was not reached (95% CI 18.21-NR). Among patients with all other metastases (n = 111), median PFS was 24.19 months (95% CI 16.33-33.82). Lower ANC was correlated with decreased risk of progression (HR 0.84, 95% CI 0.71-0.97, p = 0.008). There was no significant association between NLR and the risk of disease progression (HR 1.07, 95% CI 0.97-1.18, p = 0.203). CONCLUSION: The effectiveness of palbociclib and endocrine therapy in the treatment of HR-positive, HER2-negative mBC in the real-world setting is similar to the efficacy reported in the PALOMA-2 trial. Patients with lower neutrophil count may have a lower risk of early disease progression.

Recurrence risk of early-stage melanoma of the external ear: an investigation of surgical approach and sentinel lymph node status.

Surgical management of external ear melanoma presents unique technical challenges based on the unique anatomy and reconstruction concerns. Surgical technique, including preservation of cartilage, is variable and impact on recurrence is unclear. Our goal was to investigate surgical approach, including extent of surgical resection and sentinel lymph node biopsy (SLNB), and the impact on recurrence. In this retrospective review of primary clinical stage 1/2 external ear melanoma, demographics, tumor characteristics, surgical resection technique (including cartilage-sparing vs. cartilage removal), and SLNB results were evaluated for recurrence risk. One hundred and fifty-six patients total had an average follow-up of 5.6 years. Twenty-nine (18.6%) patients underwent cartilage-sparing surgery and 99 (63.5%) patients underwent SLNB, 14.1% of whom had micrometastatic disease. Ten (6.4%) patients recurred loco-regionally. Recurrence was associated with Breslow depth, initial stage at diagnosis, and SLNB status. Cartilage-sparing surgery was not associated with increased recurrence. Sentinel lymph node identification rate was 100% based on clinical detection with use of lymphoscintigraphy. In addition to confirming established risk factors for melanoma recurrence, we confirm the feasibility of SLNB in stratifying recurrence risk. Although we did not see an increased recurrence risk with surgical technique and cartilage-sparing approaches, these findings are limited by small sample size.

The Immune Checkpoint Kick Start: Optimization of Neoadjuvant Combination Therapy Using Game Theory.

PURPOSE: In an upcoming clinical trial at the Moffitt Cancer Center for women with stage 2/3 estrogen receptor-positive breast cancer, treatment with an aromatase inhibitor and a PD-L1 checkpoint inhibitor combination will be investigated to lower a preoperative endocrine prognostic index (PEPI) that correlates with relapse-free survival. PEPI is fundamentally a static index, measured at the end of neoadjuvant therapy before surgery. We have developed a mathematical model of the essential components of the PEPI score to identify successful combination therapy regimens that minimize tumor burden and metastatic potential, on the basis of time-dependent trade-offs in the system. METHODS: We considered two molecular traits, CCR7 and PD-L1, which correlate with treatment response and increased metastatic risk. We used a matrix game model with the four phenotypic strategies to examine the frequency-dependent interactions of cancer cells. This game was embedded in an ecological model of tumor population-growth dynamics. The resulting model predicts evolutionary and ecological dynamics that track with changes in the PEPI score. RESULTS: We considered various treatment regimens on the basis of combinations of the two therapies with drug holidays. By considering the trade off between tumor burden and metastatic potential, the optimal therapy plan was a 1-month kick start of the immune checkpoint inhibitor followed by 5 months of continuous combination therapy. Relative to a protocol giving both therapeutics together from the start, this delayed regimen resulted in transient suboptimal tumor regression while maintaining a phenotypic constitution that is more amenable to fast tumor regression for the final 5 months of therapy. CONCLUSION: The mathematical model provides a useful abstraction of clinical intuition, enabling hypothesis generation and testing of clinical assumptions.

Rigor prophylaxis in stage IV melanoma and renal cell carcinoma patients treated with high dose IL-2.

BACKGROUND: Rigors are a significant adverse event during interleukin-2 (IL2) therapy for metastatic melanoma and renal cell carcinoma. Meperidine has been a mainstay for rigor prophylaxis but there is a paucity of data regarding possible alternatives. METHODS: Ninety one patients receiving IL2 therapy for metastatic renal cell carcinoma and melanoma at Huntsman Cancer institute (HCI), Utah from May 2009 to October 2016 were retrospectively evaluated for rigor prophylaxis. Forty two patients received meperidine and 49 received tramadol. Rigors were tabulated using the proxy of number of doses of as needed (PRN) rigor medications and normalized by IL2 doses. Other outcomes of fever, hypotension, and renal insufficiency were noted on a binary scale and normalized by cycles. Statistical analysis was performed utilizing univariate and multivariate negative binomial models. RESULTS: Ninety one patients were identified with metastatic melanoma or RCC who received high dose IL2 therapy. Forty two received meperidine and 49 received tramadol prophylaxis for rigors. Univariate negative binomial analysis shows incidence rate ratios (IRR): fever 0.41 (95% CI 0.28-0.62, p-value < 0.001), hypotension 1.7 (95% CI 1.11-2.61, p-value 0.015), renal insufficiency 0.58 (95% CI 0.35-0.98, p-value 0.041), rigors per all PRN meds 1.01 (95% CI 0.79-1.28, p-value 0.964), and rigors via opioid PRN meds 0.85 (95% CI 0.67-1.07, p-value 0.168). Multivariate negative binomial analysis shows IRR: fever 0.59 (95% CI 0.28-1.24, p-value 0.163), hypotension 0.93 (95% CI 0.43-2.03, p-value 0.864), renal insufficiency 1.1 (95% CI 0.52-2.32, p-value 0.807), rigors per al PRN meds 0.92 (95% CI 0.67-1.26, p-value 0.604), and rigors via opioid PRN 0.9 (95% CI 0.65-1.26, p-value 0.554). CONCLUSION: Univariate models indicated meperidine pre-treatment was associated with significantly lower rates of fever and renal insufficiency whereas tramadol was associated with significantly lower rate of hypotension. However, when controlled for demographics and other treatment differences, these differences were no longer significant.

Neutrophil-to-lymphocyte Ratio (NLR) as a predictor for recurrence in patients with stage III melanoma.

Neutrophil-to-lymphocyte ratio is a strong predictor for overall survival and disease free survival in many cancers. Our study is the first investigation aiming to determine the predictive value of neutrophil-to-lymphocyte ratio on prognosis of patients with stage III melanoma. This retrospective study utilized a cohort of 107 patients with stage III melanoma treated at Huntsman Cancer Institute, University of Utah, from May 2002 to March 2016. The optimal cutoff of neutrophil-to-lymphocyte ratio was determined by the significance of log-rank tests. A total of 97 log-rank tests were conducted to find the optimal cutoff. Disease free survival was assessed using the Kaplan-Meier method, and univariable and multivariable Cox models were applied to evaluate the predictive value of neutrophil-to-lymphocyte ratio. 2.5 was identified as the optimal cutoff. Kaplan-Meier curve showed that the disease free survival rate of the low value group was significantly higher compared to that of high value group. After adjusting for confounders and other prognostic factors, the neutrophil-to-lymphocyte ratio ≥ 2.5 remained a strong predictor for disease recurrence in patients with stage III melanoma.

A phase I trial of azacitidine and nanoparticle albumin bound paclitaxel in patients with advanced or metastatic solid tumors.

BACKGROUND: Secreted protein acidic and rich in cysteine (SPARC), an albumin-binding protein, is downregulated by hypermethylation in many cancers. Hypomethylating agents such as azacitidine can upregulate SPARC in tumors, which may enhance the accumulation of albumin-bound drugs at tumor site. The objectives of this phase I trial was to determine the safety and maximum tolerated dose and to assess any clinical activity of the combination of azacytidine and weekly nanoparticle-albumin-bound (nab®) paclitaxel. METHODS: Patients received escalating azacytidine doses daily for 5 days, followed by nab-paclitaxel at the standard 100mg/m2 weekly dose for 3 weeks in 4-week cycles. Dose-limiting toxicities (DLTs) were monitored during the first cycle. Serum was obtained at baseline, during and after treatment for correlative study. RESULTS: All sixteen total patients enrolled were evaluable for toxicity, while 13 patients were evaluable for response. Two of five patients treated with 100mg/m2 of azacytidine had DLT of prolonged grade 4 neutropenia. Therefore, the MTD of azacitidine in this regimen is 75 mg/m2. Three additional patients were treated with no grade 4 toxicity in cycle 1. Clinical activity included 1 complete response (CR) in refractory DLBCL, 2 CR in ovarian cancer, 4 partial responses (PR) in ovarian and endometrial cancer, 4 stable diseases (SD) in lung, sarcoma and pancreatic cancer, 1 unconfirmed PR in breast cancer, and 1 progression of disease in CLL/SLL. CONCLUSIONS: Priming with azacitidine 75 mg/m2 daily for 5 days, followed by weekly nab-paclitaxel 100 mg/m2 weekly was well tolerated and results in dramatic responses pre-treated cancer patients.

A Phase I Study of Neoadjuvant Chemotherapy With Nab-Paclitaxel, Doxorubicin, and Cyclophosphamide in Patients With Stage II to III Breast Cancer.

BACKGROUND: The aims of this study were to assess the safety and tolerability of nanoparticle albumin bound paclitaxel (nab-paclitaxel), doxorubicin, and cyclophosphamide as combination therapy for breast cancer patients in the neoadjuvant setting and to assess the overall clinical response and pathologic complete response (pCR). PATIENTS AND METHODS: Twenty-six women with newly diagnosed stage II to III histologically or cytologically proven adenocarcinoma of the breast with negative HER2 status were enrolled. Patients were treated with nab-paclitaxel 100 mg/m2, doxorubicin 50 mg/m2, and cyclophosphamide 500 mg/m2 on day 1 and nab-paclitaxel 100 mg/m2 on day 8 in a 21-day cycle for 6 cycles total. RESULTS: Most adverse events attributed to treatment were decreased white blood cell count, neutropenia, anemia, thrombocytopenia, and lymphopenia with a median duration of 8 days. Fifteen of 23 (65.2%; 95% confidence interval [CI], 45.7%-84.6%) had a complete clinical response and 8 of 23 (34.7%; 95% CI, 15.2%-54.1%) had a partial clinical response for an overall clinical response rate of 100%. Thirteen of 23 patients (56.5%; 95% CI, 36.2%-76.7%) had a pCR. All 10 triple-negative breast cancer (TNBC) patients (100%) achieved a pCR. CONCLUSION: The regimen of nab-paclitaxel, doxorubicin, and cyclophosphamide chemotherapy was well tolerated and resulted in high clinical as well as pathologic responses, particularly in TNBC.

Neutrophil-to-lymphocyte ratio as prognostic indicator in gastrointestinal cancers: a systematic review and meta-analysis.

An accurate, time efficient, and inexpensive prognostic indicator is needed to reduce cost and assist with clinical decision making for cancer management. The neutrophil-to-lymphocyte ratio (NLR), which is derived from common serum testing, has been explored in a variety of cancers. We sought to determine its prognostic value in gastrointestinal cancers and performed a meta-analysis of published studies using the Meta-analysis Of Observational Studies in Epidemiology guidelines. Included were randomized control trials and observational studies that analyzed humans with gastrointestinal cancers that included NLR and hazard ratios (HR) with overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and/or cancer-specific survival (CSS).We analyzed 144 studies comprising 45,905 patients, two-thirds of which were published after 2014. The mean, median, and mode cutoffs for NLR reporting OS from multivariate models were 3.4, 3.0, 5.0 (±IQR 2.5-5.0), respectively. Overall, NLR greater than the cutoff was associated with a HR for OS of 1.63 (95% CI, 1.53-1.73; P < 0.001). This association was observed in all subgroups based on tumor site, stage, and geographic region. HR for elevated NLR for DFS, PFS, and CSS were 1.70 (95% CI, 1.52-1.91, P < 0.001), 1.64 (95% CI, 1.36-1.97, P < 0.001), and 1.83 (95% CI, 1.50-2.23, P < 0.001), respectively.Available evidence suggests that NLR greater than the cutoff reduces OS, independent of geographic location, gastrointestinal cancer type, or stage of cancer. Furthermore, DFS, PFS, and CSS also have worse outcomes with elevated NLR.

Narcoleptic-like Episodes in a Patient Receiving Pegylated Interferon-alpha 2b: A Case Report and Review of Literature.

A 26-year-old male developed narcoleptic-like episodes while on pegylated interferon-alpha 2b (peg-IFN-α2b) therapy for stage IIIB melanoma. Once peg-IFN-α2b was discontinued, the narcoleptic-like episodes eradicated. A case report and review of the literature are presented in this article.

Complete response to azacitidine priming and nab-paclitaxel in non-Hodgkin lymphoma resistant to biochemotherapy.

The standard of care for first-line therapy in diffuse large B-cell lymphoma (DLBCL) is the rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) regimen. For patients who fail to respond, have an incomplete response or relapse, numerous effective options exists besides salvage cisplatin-based regimen and autologous stem cell therapy. Even with this approach, the outcome remains very poor for this group of patients. The present case illustrates a 55-year-old woman diagnosed with DLBCL, who experienced an early incomplete response, later progression during treatment with the R-CHOP regimen. The patient received salvage therapy with rituximab, cisplatin and gemcitabine, again with an incomplete response. The patient declined consideration for stem cell therapy. Her disease progressed and she enrolled in the present phase I trial using azacitadine priming and nanoalbumin-bound (nab)-paclitaxel. After three cycles, follow-up positron emission tomography/computed tomography revealed a complete response for the first time since her initial diagnosis and the patient has remained disease-free for >6 years. Azacitadine and nab-paclitaxel combination appeared to be an effective regimen for the treatment of this patient with refractory DLBCL.

A Case Report of Pneumocystis Jiroveci Pneumonia in a Patient with Metastatic Breast Cancer.

We describe a 69-year-old woman with metastatic breast cancer who developed dyspnea on exertion, persistent cough, fever and fatigue while on everolimus and exemestane combination. The initial differentials included opportunistic infection such as pneumocystis jiroveci pneumonia (PJP) vs. pneumonitis. Bronchoalveolar lavage (BAL) from bronchoscopy revealed PJP. The patient recovered after appropriate treatment. We also correlated the progressive decrease in her absolute lymphocyte count with PJP infection and recovery. This is the second case that PJP has been described in patients with breast cancer receiving everolimus. Clinicians should be vigilant in their monitoring of patients on everolimus-based regimens and promptly institute appropriate therapy to reduce and prevent morbidity and mortality.

miR-125b regulates differentiation and metabolic reprogramming of T cell acute lymphoblastic leukemia by directly targeting A20.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematopoietic malignancy. Although it has been reported that overexpression of miR-125b leads to T-ALL development, the underlying mechanisms of miR-125b action are still unclear. The goal of this study is to delineate the role of miR-125b in T-ALL development. We found that miR-125b is highly expressed in undifferentiated leukemic T cells (CD4-negative) while its expression is low in differentiated T cells (CD4-positive). Overexpression of miR-125b increased the CD4-negative population in T cells, whereas depletion of miR-125b by miR-125b-sponge decreased the CD4-negative cell population. We identified that A20 (TNFAIP3) is a direct target of miR-125b in T cells. Overexpression of miR-125b also increased glucose uptake and oxygen consumption in T cells through targeting A20. Furthermore, restoration of A20 in miR-125b-overexpressing cells decreased the CD4-negative population in T cell leukemia, and decreased glucose uptake and oxygen consumption to the basal level of T cells transfected with vector. In conclusion, our data demonstrate that miR-125b regulates differentiation and reprogramming of T cell glucose metabolism via targeting A20. Since both de-differentiation and dysregulated glucose metabolism contribute to the development of T-cell leukemia, these findings provide novel insights into the understanding and treatment of T-ALL.

A phase I study of intratumoral ipilimumab and interleukin-2 in patients with advanced melanoma.

PURPOSE: Intratumoral interleukin-2 (IL-2) is effective but does not generate systemic immunity. Intravenous ipilimumab produces durable clinical response in a minority of patients, with potentially severe toxicities. Circulating anti-tumor T cells activated by ipilimumab may differ greatly from tumor-infiltrating lymphocytes activated by intratumoral ipilimumab in phenotypes and functionality. The objective of this study was to primarily assess the safety of intratumoral ipilimumab/IL-2 combination and to obtain data on clinical efficacy. RESULTS: There was no dose limiting toxicity. While local response of injected lesions was observed in 67% patients (95% CI, 40%-93%), an abscopal response was seen in 89% (95% CI, 68%-100%). The overall response rate and clinical benefit rate by immune-related response criteria (irRC) was 40% (95% CI, 10%-70%) and 50% (95% CI, 19%-81%), respectively. Enhanced systemic immune response was observed in most patients and correlated with clinical responses. EXPERIMENTAL DESIGN: Twelve patients with unresectable stages III/IV melanoma were enrolled. A standard 3+3 design was employed to assess highest tolerable intratumoral dose of ipilimumab and IL-2 based on toxicity during the first three weeks. Escalated doses of ipilimumab was injected into only one lesion weekly for eight weeks in cohorts of three patients. A fixed dose of IL-2 was injected three times a week into the same lesion for two weeks, followed by two times a week for six weeks. CONCLUSIONS: Intratumoral injection with the combination of ipilimumab/IL-2 is well tolerated and generates responses in both injected and non-injected lesions in the majority of patients.

miR-125b functions as a key mediator for snail-induced stem cell propagation and chemoresistance.

Chemoresistance is a major obstacle in cancer treatment. Our previous studies have shown that miR-125b plays an important role in chemoresistance. Here we report a novel mechanism that up-regulation of miR-125b through Wnt signaling by Snail enriches cancer stem cells. Overexpression of Snail dramatically increases the expression of miR-125b through the Snail-activated Wnt/ß-catenin/TCF4 axis. Snail confers chemoresistance by repressing Bak1 through up-regulation of miR-125b. Restoring the expression of Bak1 or depleting miR-125b re-sensitizes Snail-expressing cancer cells to Taxol, indicating that miR-125b is critical in Snail-induced chemoresistance. Moreover, overexpression of miR-125b significantly increases the cancer stem cell population (CD24-CD44+), while depletion of miR-125b or rescue of the expression of Bak1 increases the non-stem cell population (CD24+CD44+) in Snail-overexpressing cells. These findings strongly support that miR-125b functions as a key mediator in Snail-induced cancer stem cell enrichment and chemoresistance. This novel mechanism for Snail-induced stem cell propagation and chemoresistance may have important implications in the development of strategies for overcoming cancer cell resistance to chemotherapy.

Activated CD4+ T cells enhance radiation effect through the cooperation of interferon-gamma and TNF-alpha.

BACKGROUND: Approaches that enhance radiation effect may lead to improved clinical outcome and decrease toxicity. Here we investigated whether activated CD4+ T cells (aCD4) can serve as an effective radiosensitizer. METHODS: CD4+ T cells were activated with anti-CD3 and anti-CD28 mAbs. Hela cells were presensitized with aCD4 or conditioned supernatant (aCD4S) or recombinant cytokines for 2 days, followed gamma-irradiation. The treated cells were cultured for an additional 2 to 5 days for cell proliferation, cell cycle, and western blot assays. For confirmation, other cancer cell lines were also used. RESULTS: Presensitization of tumor cells with aCD4 greatly increased tumor cell growth inhibition. Soluble factors secreted from activated CD4+ T cells were primarily responsible for the observed effect. IFN-gamma seemed to play a major role. TNF-alpha, though inactive by itself, significantly augmented the radiosensitizing activity of IFN-gamma. aCD4S, but not IFN-gamma or IFN-gamma/TNF-alpha combination, was found to enhance the gamma-irradiation-induced G2/M phase arrest. Bax expression was highly upregulated in Hela cells presensitized with aCD4S followed by gamma-irradiation. The radio-sensitizing activity of aCD4 is not uniquely observed with Hela cell line, but also seen with other cancer cell lines of various histology. CONCLUSIONS: Our findings suggest possible molecular and cellular mechanisms that may help explain the radio-sensitization effect of activated lymphocytes, and may provide an improved strategy in the treatment of cancer with radiotherapy.

Mitf-Mdel, a novel melanocyte/melanoma-specific isoform of microphthalmia-associated transcription factor-M, as a candidate biomarker for melanoma.

BACKGROUND: Melanoma incidence is on the rise and advanced melanoma carries an extremely poor prognosis. Treatment options, including chemotherapy and immunotherapy, are limited and offer low response rates and transient efficacy. Thus, identification of new melanocyte/melanoma antigens that serve as potential novel candidate biomarkers in melanoma is an important area for investigation. METHODS: Full length MITF-M and its splice variant cDNA were cloned from human melanoma cell line 624 mel by reverse transcription polymerase chain reaction (RT-PCR). Expression was investigated using regular and quantitative RT-PCR in three normal melanocytes (NHEM), 31 melanoma cell lines, 21 frozen melanoma tissue samples, 18 blood samples (peripheral blood mononuclear cell; PBMC) from healthy donors and 12 non-melanoma cancer cell lines, including three breast, five glioma, one sarcoma, two kidney and one ovarian cancer cell lines. RESULTS: A novel splice variant of MITF-M, which we named MITF-Mdel, was identified. The predicted MITF-Mdel protein contains two in frame deletions, 56- and 6- amino acid deletions in exon 2 (from V32 to E87) and exon 6 (from A187 to T192), respectively. MITF-Mdel was widely expressed in melanocytes, melanoma cell lines and tissues, but almost undetectable in non-melanoma cell lines or PBMC from healthy donors. Both isoforms were expressed significantly higher in melanoma tissues than in cell lines. Two of 31 melanoma cell lines expressed only one isoform or the other. CONCLUSION: MITF-Mdel, a novel melanocyte/melanoma-specific isoform of MITF-M, may serve as a potential candidate biomarker for diagnostic and follow-up purposes in melanoma.

Demethylating Agents in the Treatment of Cancer.

Gene silencing resulting from aberrant DNA methylation can lead to tumorigenesis. Therefore, drugs that inhibit or interfere with DNA methylation have been used to reactivate and induce silenced gene re-expression in malignancies. Two demethylating agents, azacitidine and decitabine, are approved for the treatment of myelodysplastic syndromes (MDS) by the U.S. Food and Drug Administration (FDA), and are now considered the standard of care in MDS. In this review, we discuss clinical data, including clinical benefits and toxicities, which led to the approval of azacitidine and decitabine. We also summarize findings from clinical trials that used these two demethylating agents in the treatment of solid tumors. Lastly, we discuss some limitations in the use of azacitidine and decitabine in cancer therapy.

Activated CD4+ T cells dramatically enhance chemotherapeutic tumor responses in vitro and in vivo.

Chemoimmunotherapy has been widely studied in melanoma, with various degrees of success. One of the most common approaches is the so-called biochemotherapy, which is associated with increased toxicities, but without overall survival benefit. Another conventional strategy is the use of chemotherapy as an immunomodulator to enhance the effect of cancer vaccines or adoptive cell transfer therapy. Based on this approach, recent studies using chemotherapy to prepare the host before the infusion of ex vivo-activated, melanoma Ag-specific tumor-infiltrating lymphocytes and high dose IL-2 resulted in an impressive response rate. However, the development of immunotherapy for the treatment of a broad range of cancer type is still lacking. In this study, we report the development of a simple yet universal approach termed "chemocentric chemoimmunotherapy" that has potential application in the treatment of all cancer types. This technique uses nonspecifically activated CD4(+) T cells as a chemosensitizer before the administration of chemotherapy. Dramatic enhancement of the cytotoxic effect of chemotherapeutic drugs, either active or nonactive as single agents, was observed both in in vitro and in vivo human tumor xenograft models. Soluble factors secreted from activated CD4(+) T cells, likely acting on the tumor and its microenvironment, were responsible for the observed effect. Although IFN-gamma played a major role in the therapeutic outcome, it was consistently found to be inferior to the use of activated CD4(+) T cells in tumor chemosensitization. Our model may provide a plausible mechanism to facilitate further understanding, design and development of improved chemoimmunotherapy in the treatment of cancer.