Biomedical subjects

Jorg Michels

Publications and source records attributed to Jorg Michels.

5 recordsLinked to original sources

PubMed2006

First- and second-line chemotherapy with docetaxel or mitoxantrone in patients with hormone-refractory prostate cancer: does sequence matter?

BACKGROUND: Docetaxel and mitoxantrone are considered first-line chemotherapeutic options in patients with hormone-refractory prostate cancer (HRPC), but their clinical effectiveness in a second-line setting is unknown. Therefore, the authors conducted a population-based retrospective study to establish activity and tolerability of second-line docetaxel or mitoxantrone in HRPC. METHODS: The study included 68 patients who had failed androgen ablation therapy and who received docetaxel and mitoxantrone in either sequence. Clinical efficacy in terms of median overall survival (OS), progression-free survival (PFS), posttreatment prostate-specific antigen (PSA) decline of > or = 50% and treatment-related toxicity were evaluated. RESULTS: Of 68 patients, 35 received docetaxel followed by mitoxantrone, and 33 received mitoxantrone followed by docetaxel. Both groups were comparable for recognized pretreatment prognostic factors. Patients who received docetaxel first-line had a trend toward longer median OS compared with patients treated with second-line docetaxel after mitoxantrone failure (22 mos, 95% confidence interval [CI], 17.2-26.8 mos vs. 15 mos, 95% CI, 10.4-19.6 mos). Median number of second-line chemotherapy cycles was 3 and median PFS survival was 2-3 months in both groups. Second-line docetaxel produced a higher PSA response compared with mitoxantrone (38% vs. 12%, P = 0.012), but this did not translate to a survival benefit. Both second-line docetaxel and mitoxantrone were associated with a high frequency of treatment-related adverse events that resulted in dose reduction, delay, or discontinuation (64% and 46% of patients, respectively). CONCLUSIONS: Study results favored docetaxel given up-front for patients with HRPC considered suitable for further chemotherapy. Second-line docetaxel or mitoxantrone had limited efficacy and tolerability. Patients who are candidates for second-line chemotherapy, should be enrolled into clinical trials.

Aged↗

PubMed2006

Immunohistochemical analysis of the antiapoptotic Mcl-1 and Bcl-2 proteins in follicular lymphoma.

In the present study, we investigated the expression of Mcl-1 and Bcl-2 by immunohistochemistry in 85 patients of grades 1-3 and transformed follicular lymphoma (FL). In lymphoma tissue, centroblasts uniformly expressed high levels of Mcl-1 (Mcl-1(hi)) whereas centrocytes demonstrated low Mcl-1 expression (Mcl-1(lo)). Bcl-2 expression in centroblasts/centrocytes was reciprocal to Mcl-1 staining in most cases. A high number of Mcl-1(hi) centroblasts in tissue sections (> or =200/high-power field) correlated with poor overall survival (P < 0.001), independent of the International Prognostic Index and FL grade. This suggests that the number of centroblasts with strong Mcl-1 staining is associated with clinical outcome in FL patients.

Adult↗

PubMed2005

Mcl-1.

Mcl-1 is a Bcl-2 family protein which can act as an apical molecule in apoptosis control, promoting cell survival by interfering at an early stage in a cascade of events leading to release of cytochrome c from mitochondria. Mcl-1 has a short half life and is a highly regulated protein, induced by a wide range of survival signals and also rapidly down regulated during apoptosis. Mcl-1 can also readily be cleaved by caspases during apoptosis to produce a cell death promoting molecule. The multiple levels of control of Mcl-1 expression suggest that Mcl-1 plays a critical role in controlling life and death decisions in response to rapidly changing environmental cues and Mcl-1 is required for embryonic development and the function of the immune system. Expression of Mcl-1 may be useful in informing decision making in the treatment of various cancers, and countering Mcl-1 function may be an attractive therapeutic strategy in malignancy, inflammatory conditions and infectious disease where Mcl-1 may play a major role in suppressing apoptosis.

Animals↗

PubMed2004

Mcl-1 is required for Akata6 B-lymphoma cell survival and is converted to a cell death molecule by efficient caspase-mediated cleavage.

Enforced expression of the antiapoptotic Bcl-2 family protein Mcl-1 promotes lymphomagenesis in the mouse; however, the functional role of Mcl-1 in human B-cell lymphoma remains unclear. We demonstrate that Mcl-1 is widely expressed in malignant B-cells, and high-level expression of Mcl-1 is required for B-lymphoma cell survival, since transfection of Mcl-1-specific antisense oligodeoxynucleotides was sufficient to promote apoptosis in Akata6 lymphoma cells. Mcl-1 was efficiently cleaved by caspases at evolutionarily conserved aspartic acid residues in vitro, and during cisplatin-induced apoptosis in B-lymphoma cell lines and spontaneous apoptosis of primary malignant B-cells. Overexpression of the Mcl-1 cleavage product that accumulated during apoptosis was sufficient to kill cells. Therefore, Mcl-1 is an essential survival molecule for B-lymphoma cells and is cleaved by caspases to a death-promoting molecule during apoptosis. In contrast to Mcl-1, Bcl-2 and Bcl-XL were relatively resistant to caspase cleavage in vitro and in intact cells. Interfering with Mcl-1 function appears to be an effective means of inducing apoptosis in Mcl-1-positive B-cell lymphoma, and the unique sensitivity of Mcl-1 to caspase-mediated cleavage suggests an attractive strategy for converting it to a proapoptotic molecule.

Apoptosis↗

PubMed2002

Induction chemotherapy strategies for primary mediastinal large B-cell lymphoma with sclerosis: a retrospective multinational study on 426 previously untreated patients.

BACKGROUND AND OBJECTIVES: This multinational retrospective study compares the outcomes of patients with primary mediastinal large B-cell lymphoma (PMLBCL) with sclerosis after first-generation (dose-intensive regimens), third-generation (alternating regimens) and high-dose chemotherapy strategies, frequently with adjuvant radiation therapy. DESIGN AND METHODS: Between August 1981 and December 1999, a total of 426 previously untreated patients with confirmed diagnosis were enrolled in 20 institutions to receive combination chemotherapy with either first generation (CHOP or CHOP-like) regimens, third generation (MACOP-B, VACOP-B, ProMACE CytaBOM) regimens or high-dose chemotherapy (HDS/ABMT). RESULTS: With chemotherapy, complete response (CR) rates were 49% (50/105), 51% (142/277) and 53% (23/44) with first generation, third generation and high-dose chemotherapy strategies, respectively; partial response (PR) rates were 32%, 36% and 35%, respectively. All patients who achieved CR and 124/142 (84%) with PR had radiation therapy on the mediastinum. The final CR rates became 61% for CHOP/CHOP-like regimens, 79% for MACOP-B and other regimens, and 75% for HDS/ABMT. After median follow-ups from attaining CR of 48.5 months for CHOP/CHOP-like regimens, 51.7 months for MACOP-B type regimens and 32.4 months for HDS/ABMT, relapses occurred in 15/64 (23%), 27/218 (12%) and 0/33 (0%) patients, respectively. Projected 10-year progression-free survival rates were 35%, 67% and 78%, respectively (p=0.0000). Projected 10-year overall survival rates were 44%, 71% and 77%, respectively (p=0.0000), after median follow-ups from diagnosis of 52.3 months, 54.9 months and 35.8 months, respectively. INTERPRETATION AND CONCLUSIONS: In patients with PMLBCL with sclerosis, MACOP-B plus radiation therapy may be a better strategy than other treatments; these retrospective data need to be confirmed by prospective studies. The encouraging survival results after high dose chemotherapy require confirmation in selected high-risk patients.

Adolescent↗