Summary Human invariant natural killer (iNK) T cells expressing an invariant Vα24‐Jα15 T‐cell receptor (TCR) are thought to be important regulators of autoimmunity and tumour surveillance. Two major subsets of iNK T cells, CD4 + or CD4 − CD8 − are known to exist, but the in vivo importance of CD4 expression is unclear. Since interleukin‐12 (IL‐12) is a key iNK T‐cell‐activating cytokine, the effect of IL‐12 plus or minus the T‐cell growth factor IL‐2 on a large panel of CD4 + versus CD4 − CD8 − iNK T‐cell clones was examined. Strikingly, IL‐12 and IL‐2 significantly activated iNK T cells to secrete IL‐4, interferon‐γ and granulocyte–macrophage colony‐stimulating factor, and up‐regulated perforin expression in the absence of TCR stimulation. Furthermore, IL‐2 and IL‐12 treatment resulted in a preferential increase in apoptosis of CD4 − CD8 − clones. Thus, independent of TCR activation, IL‐2 and IL‐12 can directly activate iNK T cells and provide a selective advantage to the CD4 + iNK T‐cell population.
Chemotherapy is frequently used in the treatment of advanced breast cancer. The identification of patient-specific tumor characteristics that can improve the ability to predict response to chemotherapy would help optimize advanced breast cancer treatment approaches. Quantitative immunofluorescence (QIF) may be applied to the standardization of protein analysis, resulting in increased sensitivity and reproducibility. In the current pilot study, QIF was used to correlate the expression of beta tubulin III and thymidylate synthase with clinical outcome associated with taxane and capecitabine treatment, respectively. QIF analysis is based on fluorescent dye-labeled monoclonal antibody staining followed by computer-assisted microscopy to measure the expression of molecular markers in tumor samples derived from a retrospective database. The interpretation of the tumor marker expression levels results in classification of breast tumors as sensitive or resistant to a mechanistically related drug. Overall diagnostic accuracy of QIF for taxane based therapy was 88% (CI 75.0 - 95.3) with a positive predictive value of 86% and a negative predictive value of 100%, while diagnostic accuracy QIF for capecitabine therapy was 86% (CI 88.0-96.0) with a positive predictive value of 80% and a negative predictive value of 100%. In this study, QIF showed retrospectively a potential for predictive value when analyzing chemotherapeutic treatments for individual advanced stage breast cancer patients. The predictive power of the QIF for chemotherapy confirms that further studies utilizing larger clinical cohorts are warranted.
The aims of this study were to evaluate the safety and efficacy of all-trans retinoic acid (ATRA) in the treatment of the accelerated and blastic phase of chronic myeloid leukemia (CML) and to evaluate in vitro correlates of biological activity. ATRA was administered in an intermittent schedule to patients with CML in the accelerated or blastic phases for a 6 week induction period, which was continued if there was evidence of clinical response or stable disease. If the patient was progressing at 6 weeks, interferon-alpha could be added to the ATRA. Laboratory correlative studies were performed prior to treatment and at intervals during treatment to evaluate effects on maturation and differentiation, and on CML progenitor cell growth by assessment of colony-forming cells (CFC). Eighteen patients were enrolled. There was 1 complete response, 1 partial response and 2 with hematological improvement. A fifth patient was stable on ATRA and interferon for several months. Laboratory data for the responders demonstrated high sensitivity of primary CFC to ATRA prior to treatment and low serial CFC counts on ATRA therapy. ATRA demonstrated clinical and hematological activity in 5 of 18 patients with the accelerated phase of CML, and there was evidence of a biological effect in laboratory studies of 3 of the 5 patients' progenitor cells. Combination therapy with other differentiating agents may be useful in this disease.
<p>Supplementary Figure S2. K40R α-tubulin does not affect proliferation in MDA-MB-231 or BT-549 cells but decreases McTN frequency under transient transfection conditions.</p>
<p>Supplementary Figure S1. Detyrosinated α-tubulin is not elevated in metastatic breast tumor cell lines, while acetylated α-tubulin is maintained under suspended conditions and correlates with more numerous McTNs in metastatic breast cancer cells.</p>
