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PubMed2006

Testing for different rates of continuous trait evolution using likelihood.

Rates of phenotypic evolution have changed throughout the history of life, producing variation in levels of morphological, functional, and ecological diversity among groups. Testing for the presence of these rate shifts is a key component of evaluating hypotheses about what causes them. In this paper, general predictions regarding changes in phenotypic diversity as a function of evolutionary history and rates are developed, and tests are derived to evaluate rate changes. Simulations show that these tests are more powerful than existing tests using standardized contrasts. The new approaches are distributed in an application called Brownie and in r8s.

Animals↗
PubMed1991

Philadelphia-negative (Ph-) chronic myeloid leukemia (CML): comparison with Ph+ CML and chronic myelomonocytic leukemia. The Groupe Français de Cytogénétique Hématologique.

To better understand the Philadelphia-negative (Ph-) chronic myeloid leukemia (CML) and its relationships with Philadelphia-positive (Ph+) CML and chronic myelomonocytic leukemia (CMML), a study was undertaken by the Groupe Français de Cytogénétique Hématologique. Thirty-five Ph- CML patients were investigated and compared with 55 chronic phase Ph+ CML and 100 CMML patients. There were 12 M-BCR positive (M-BCR+) and 23 M-BCR negative (MBCR+) patients. No clinical or biologic differences were found between Ph+ and Ph-, M-BCR+ patients. In the Ph- group, M-BCR+ and M-BCR- patients differed significantly in age (47.7 +/- 6.6 v 67.0 +/- 6.1 years, respectively; P = .001), leukocytosis (153.4 +/- 135.1 v 58.5 +/- 37.7 10(9)/L, P = .002), relative monocytosis (1.8% +/- 1.2% v 5.6% +/- 1.4%, P = .048), absolute basophilia (8.5 +/- 9.7 v 0.9 +/- 1.5 10(9)/L, P = .001), percentage of immature myeloid precursors (IMP) in peripheral blood (29.0% +/- 9.5% v 15.3% +/- 8.1%, P = .001), and percentage of erythroblasts in bone marrow (BM) (6.5% +/- 3.5% v 14.6% +/- 3.6%, P = .001). Karyotypic abnormalities other than the Ph chromosome occurred in 0 of 12 M-BCR- at diagnosis and 7 of 23 M-BCR- Ph- CML (P = .033). None of the 13 investigated BCR- patients had detectable BCR/ABL transcripts using polymerase chain reaction (PCR) and none had an N-RAS mutation. Cytologic findings showed a marked morphologic difference between M-BCR+ and M-BCR- patients, especially in the monocytic lineage. Dysmyelopoietic features in CMML and M-BCR- patients were very similar, and the differences were of quantitative order only. Using four criteria (monocytosis, percentage of IMP, basophilia, and percentage of erythroblasts in BM), patients could be divided into typical and atypical CML and this classification correlated well with molecular findings. We conclude that, while Ph-, M-BCR+, and Ph+ CML are identical diseases, Ph-, M-BCR- CML, and CMML have many similarities and might be only different aspects of a same entity.

Adult↗
PubMed1990

Importance of phenotypic and molecular characterization for identification of a neuroepithelioma tumor cell line, NUB-20.

A neuroblastic-like cell line (NUB-20) was derived from a case of histopathologically diagnosed metastatic neuroblastoma. The metastatic tumor and nude mouse heterotransplant resembled neuroblastoma by histological criteria, in contrast to the primary tumor, which was differentially classified as Ewing's sarcoma. However, the cell line demonstrated a unique phenotype in culture with respect to morphology, immunohistochemical markers, and sensitivity to a battery of differentiation modulators. These characteristics, together with the presence of a chromosomal translocation (11;22),(q24;q12) and amplification with enhanced expression of the c-myc protooncogene rather than N-myc, established this tumor as neuroepithelioma. Neuroepithelioma is a tumor type distinct from, but related to, neuroblastoma in its development from the neural crest lineage. These results emphasize the growing importance of cytogenetic and molecular markers in the classification and characterization of human tumors.

Bucladesine↗
PubMed1994

[Liver cancer: diagnostic possibilities and value of pathology].

The high differentiation of treatment options for patients with liver carcinoma resulted in more extensive questions to the pathologist. Resection rate for HCC is about 30%, thus the multitude of diagnoses has to be made on biopsies. An histological (rarely cytological) diagnosis has to be the section specimens with regard to typing, grading, R classification and results of studies on molecular pathology of this tumor. Essential statements on resection specimens include pTNM classification, R classification, typing, and grading. Based on these data, more parameters expected to be of prognostic value can be evaluated.

Biopsy↗
PubMed1993

[New findings in chronic granulomatous disease].

Chronic granulomatous disease is a rare hereditary disease characterized by repeated infections affecting in particular the skin, lymph nodes and internal organs. Histological examination in the affected tissues reveals a granulomatous inflammation. The aetiological agents of infection are most frequently staphylococci, G-bacteria, Candida and Aspergillus. From the immunological aspect it is an inborn immunodeficiency affecting professional phagocytes (monocytes and granulocytes) which are unable to kill some ingested microorganisms. The molecular basis of the defect is affection of the NADPH oxidase enzyme complex at various sites which explains the genetic heterogeneity of the disease. The condition is usually manifested in early childhood, it has a variable course; if untreated, the affected subjects frequently die in child age. By early diagnosis of the disease and suitable therapy the quality of life of the patients can be improved, serious complications can be prevented and the patients may reach adult age. The submitted paper is a review of contemporary knowledge of the disease, in particular its molecular basis and ensuing classification, as well as possible diagnosis and treatment of the disease. Several case-histories are presented.

Adolescent↗
PubMed1998

Genitourinary cancers in older adults.

Prostate and bladder carcinoma are, in large part, diseases of older adults, and they are discussed in this context. Pathology, diagnosis, and staging are reviewed. Surgical and medical approaches to these malignancies, and the limitations of these approaches, are highlighted. Renal cell carcinoma, while a relatively rare neoplasm, remains a formidable challenge: approximately 50% of patients die within 5 years of diagnosis. Advances in molecular genetics and histopathologic classification, as well as surgical management and investigational therapies, are emphasized.

Aged↗
PubMed1996

Mantle cell lymphoma. A morphological, immunohistochemical and molecular genetic study.

In order to identify helpful markers in the classification of mantle cell lymphoma, a morphological, immunohistochemical and molecular genetic analysis of 41 cases of NHL, originally referred to us as CC, ILL or IDL, was performed. We revised these lymphomas using the strict morphological criteria described in the updated Kiel classification and the more recently described criteria for MCL. The term MCL was used to designate the small lymphocytic B-cell NHL, previously referred to as CC or ILL/ IDL. This revision yielded 20 MCL, 8 CLL, 3 Cb/Cc, 1 CB, 6 IC and 3 MALT lymphomas. The presence of scattered histiocytes was seen in 90% of MCL and 5% of the other cases. No other morphological parameter, besides the used criteria, differentiated between MCL and similar small lymphocytic B cell lymphomas. Helpful immunohistochemical markers to distinguish MCL from similar small lymphocytic lymphomas were CD5+, CD10-, CD23- and Alkaline Phosphatase+. Large fields of dendritic reticulum cells, often in a loose and disrupted arrangement were seen in 82% of MCL and in 19% of the other lymphomas. Analysis with Southern blotting showed a rearrangement in the BCL-1 locus in 12/20 cases of MCL but not in the other 21 lymphomas. Although very specific for MCL, Southern blotting to detect BCL-1 rearrangements is, due to the large number of probes necessary, not of great help in daily practice for routine diagnostic purposes. We conclude that using strict morphological criteria, the diagnosis MCL can be made reliably and that immunophenotyping is helpful in supporting the diagnosis.

Humans↗
PubMed2002

The WHO classification of tumors of the nervous system.

The new World Health Organization (WHO) classification of nervous system tumors, published in 2000, emerged from a 1999 international consensus conference of neuropathologists. New entities include chordoid glioma of the third ventricle, cerebellar liponeurocytoma, atypical teratoid/rhabdoid tumor, and perineurioma. Several histological variants were added, including tanycytic ependymoma, large cell medulloblastoma, and rhabdoid meningioma. The WHO grading scheme was updated and, for meningiomas, extensively revised. In recognition of the emerging role of molecular diagnostic approaches to tumor classification, genetic profiles have been emphasized, as in the distinct subtypes of glioblastoma and the already clinically useful 1p and 19q markers for oligodendroglioma and 22q/INI1 for atypical teratoid/rhabdoid tumors. In accord with the new WHO Blue Book series, the actual classification is accompanied by extensive descriptions and illustrations of clinicopathological characteristics of each tumor type, including molecular genetic features, predictive factors, and separate chapters on inherited tumor syndromes. The 2000 WHO classification of nervous system tumors aims at being used and implemented by the neuro-oncology and biomedical research communities worldwide.

Humans↗
PubMed2002

Towards a new understanding and classification of chondrogenic neoplasias of the skeleton--biochemistry and cell biology of chondrosarcoma and its variants.

Despite substantial knowledge on the clinicopathology of chondrogenic skeletal neoplasms, only limited insights into the biology of the different tumor variants are available. There are virtually no established molecular markers for identification and classification of these neoplasms. In this paper, we present a systematic review of the biochemistry and cell biology of chondrogenic neoplasms of the bone focussing on our own recent investigations. The hallmark of all differentiated chondrogenic tumors is the presence of neoplastic chondrocytic cells responsible for the formation of the characteristic cartilaginous tumor matrix. These cells can show the full differentiation potential of physiologic chondrocytes depending on the tumor entity investigated. The high phenotypic diversity of physiologic chondrocytes explains the previously poorly understood, striking heterogeneity of the neoplastic cells and their surrounding extracellular matrix not only between different but also within chondrogenic tumors. In our studies, tumor classifications, so far based only on histomorphological criteria, were either confirmed or corrected: mesenchymal chondrosarcomas represent the prototypic neoplasm of pre-chondrogenic undifferentiated cells undergoing multifocal chondrocytic differentiation. Enchondromas, osteochondromas, and conventional chondrosarcomas are neoplasms of multi-phenotypically differentiated chondrocytes. Clear cell chondrosarcomas appear to be neoplasms of hypertrophic chondrocytic cells. A peculiar biology is displayed by dedifferentiated chondrosarcomas, which at least in most cases show neither "anaplasia" nor "dedifferentiation", but most likely "transdifferentiation" of part of the neoplastic cells to a cellular phenotype of a different mesenchymal differentiation lineage. Chondroblastomas do not show any chondroblastic differentiation at all. Our studies delineate molecular markers of chondrogenic neoplasms of the skeleton, which have the potential to be the basis of a new biology-orientated classification of skeletal neoplasms. The expression analysis of extracellular matrix genes, in particular of the collagen types, might be able to play herein a leading role in classification and diagnosis, similar to the cytokeratin subtypes or the CDs (cluster of differentiation) for the classification and diagnosis of neoplasms of the epithelia and the lymphatics.

Animals↗
PubMed2005

Precursor lesions of invasive breast cancer.

The increasing application of mammography, mainly in screening programs for the early detection of breast cancer, and the high technical standard of imaging has resulted in the detection of clinically occult breast tumors. Considering that only diagnosis at an early stage will be able to change the prognosis of breast cancer, this diagnostic challenge appears to be the most exciting field in both breast imaging and breast pathology. Especially the precursor lesions need to be diagnosed and defined precisely to understand their prognostic significance. In imaging, the morphologic appearance of precursor lesions is usually neither typical nor pathognomonic. They have to be assessed histologically using percutaneous interventions. Recent molecular studies have demonstrated various genetic alterations in the ductal epithelium, with the earliest onset in atypical ductal hyperplasia. The recent WHO classification, which is based on molecular data and histopathological features, attempts to define in particular the precursor lesions and low grade intraductal carcinomas. The clinical importance of the various grades has to be assessed. Intimate cooperation between diagnostic radiologist and pathologist is essential.

Breast Neoplasms↗
PubMed1999

Molecular pathology of colorectal cancer.

The identification of several types of familial colorectal cancer has led to the discovery of some of the genes involved in these diseases. It was subsequently shown that somatic mutations of these genes (APC, mismatch repair genes, TP53, KRAS, and DCC) also occur in sporadic colorectal cancer. Gradually, this molecular information is being incorporated into the standard histopathological analysis of colorectal cancer and can be used for the characterization of primary tumors. Although attempts have been made to use molecular parameters to better define dysplasia grades, differentiate between adenoma and carcinoma, and subtype carcinomas, histological parameters remain the standard for the classification of primary tumors. Nonetheless, molecular parameters may help define subgroups of colorectal carcinoma differing in prognosis and requiring individualized treatment regimens. Interesting possibilities are predicting the response to chemotherapy or radiotherapy at a molecular level and the search for metastasis by looking for molecular markers in lymph nodes or circulating blood. Other pathological tests being developed include the detection of KRAS, TP53, or APC mutations in stool and plasma. Such approaches will have a significant impact on the clinical management of colorectal cancer.

Adenoma↗
PubMed1999

[Molecular pathology of colorectal cancer].

The identification of several types of familial colorectal cancer has led to the discovery of some of the genes involved in these diseases. It was subsequently shown that somatic mutations of these genes (APC, mismatch repair genes, TP53) also occur in sporadic colorectal cancer. Gradually, this molecular information is being incorporated into the standard histopathological analysis of colorectal cancer and can be used for the characterization of primary tumors. Although attempts have been made to use molecular parameters to better define dysplasia grades, differentiate between adenoma and carcinoma, and subtype carcinomas, histological parameters remain the standard for the classification of primary tumors. Nonetheless, molecular parameters may help define subgroups of colorectal carcinoma differing in prognosis and requiring individualized treatment regimens. Interesting possibilities are predicting the response of chemotherapy or radiotherapy at a molecular level and the search for metastasis by looking for molecular markers in lymph nodes or circulating blood. Other pathological tests being developed include the detection of K-ras, TP53 or APC mutations in stool and plasma. Such approaches will have a significant impact on the clinical management of colorectal cancer.

Biomarkers, Tumor↗
PubMed1990

[Osteogenesis imperfecta, but which one?].

Osteogenesis imperfecta is an heterogeneous group of inherited disorders of type I collagen and of the matrix. Heterogeneity concerns molecular determinism, clinical expression and genetic risk. For the purpose of clinical management, five situations are to be distinguished, according to Sillence classification. Biochemical studies afford a molecular basis for understanding clinical heterogeneity and demonstrate an autosomal dominant transmission in most cases, even the more severe forms.

Collagen↗
PubMed2003

[Lymphoma prognostic correlated factors analysis of 88 cases].

OBJECTIVE: To analyze the characters of incidence, pathological and immunological phenotype of malignant lymphoma(ML), and to study the significance of IgH and TCR T cell receptor gene rearrangement for NHL typing. METHODS: Immunological phenotyping was conducted by SABC, and IgH (FR2A, FR3A) & TCR (beta,gamma) gene rearrangement detected by PCR of some pathological wax and bone marrow samples. RESULTS: (1) In ML, the percentage of non-Hodgkin lymphoma, (NHL) was 88.6% and Hodgkin lymphoma (HL) was 11.4%. The incidence increased with the patient's age. The percentage of patients over 60 years was 38.6%, and the median survival time of those older than 60 years was significantly shorter than that of the younger. (2) The percentage of B-NHL was 68.6%, and that of T-NHL was 28.6%; 3 years' survival time rate of B-NHL was higher than that of T-NHL. (3) The percentage of low grade NHL was 42%, and that of middle and high grade NHL was 58%; and the overall survival time was not significantly different between the two groups. But the overall survival time was longer in patients in stages I-II than in stages III-IV. (4) The results of detection on wax and bone marrow samples showed that B-NHL FR2A were 66.7% and 56.2% positive, FR3A 90.4% and 81.2% positive; in T-NHL patients, TCR-beta and TCR-gamma gene rearrangements were 91.7% and 75.0% positive; T and B classification were the same as the immunological phenotype. CONCLUSION: Age, T and B classifications and staging are the important factors, which affect the prognosis of NHL. Molecular biological methods can help T/B classification when we couldn't get it by phenotyping.

Factor Analysis, Statistical↗
PubMed2006

Evolution of funnel-revolver flowers and ornithophily in nasa (loasaceae).

Floral morphology, distribution, and flower visitors for 60 taxa of Nasa are investigated and compared to molecular trees inferred both from a combined marker analysis (ITS1 and trnL (UAA)) and from a single marker (ITS1). Flowers conform to two different floral types: Firstly, "tilt-revolver flowers", with spreading to reflexed, white to yellow petals and small, brightly coloured floral scales contrasting with the petals and firmly enclosing the nectar (Saccatae and Carunculatae); secondly, "funnel-revolver flowers", with half-erect to erect, orange to red petals and floral scales not contrasting with the petals, or enclosed in the corolla, and nectar freely accessible by funnel-shaped floral scales ( Alatae, Grandiflorae, and N. venezuelensis species group). Phylogenetic analysis shows that "tilt-revolver flowers" represent the plesiomorphic condition by outgroup comparison. The two groups with tilt-revolver flowers in Nasa are not monophyletic ( Saccatae are paraphyletic, Carunculatae are polyphyletic). Most Saccatae fall into two monophyletic assemblages, the N. poissoniana species group and the N. triphylla species group. The remainder of Saccatae group either with Grandiflorae ( N. insignis species group) or with Alatae ( N. laxa species group). The clades retrieved in the molecular analysis contradict the traditional classification, but are congruent with vegetative morphology, details of the flower morphology, and biogeography. "Funnel-revolver flowers" represent the derived condition, but molecular data suggest a convergent development (at least twice independently), since the corresponding species do not constitute a monophyletic group. "Tilt-revolver flowers" are visited and pollinated by bees (especially Colletidae), whereas "funnel-revolver flowers" are mostly visited by hummingbirds. The transition from melittophily to ornithophily may have been the license for the colonization of, and the diversification in, both cloud forest and high Andean habitats.

Animals↗
PubMed2004

Ductal carcinoma in situ, complexities and challenges.

The incidence of ductal carcinoma in situ (DCIS), a noninvasive form of breast cancer, has increased markedly in recent decades, and DCIS now accounts for approximately 20% of breast cancers diagnosed by mammography. Laboratory and patient data suggest that DCIS is a precursor lesion for invasive cancer. The appropriate classification of DCIS has provoked much debate; a number of classification systems have been developed, but there is a lack of uniformity in the diagnosis and prognostication of this disease. Further investigation of molecular markers should improve the classification of DCIS and our understanding of its relationship to invasive disease. Controversy also exists with regard to the optimal management of DCIS patients. In the past, mastectomy was the primary treatment for patients with DCIS, but as with invasive cancer, breast-conserving surgery has become the standard approach. Three randomized trials have reported a statistically significant decrease in the risk of recurrence with radiation therapy in combination with lumpectomy compared with lumpectomy alone, but there was no survival advantage with the addition of radiotherapy. Two randomized trials have suggested an additional benefit, in terms of recurrence, with the addition of adjuvant tamoxifen therapy, although in one trial the benefit was not statistically significant. Current data suggest that tamoxifen use should be restricted to patients with estrogen receptor-positive DCIS. Neither trial demonstrated a survival benefit with adjuvant tamoxifen. Ongoing and recently completed studies should provide information on outcomes in patients treated with lumpectomy alone and on the effectiveness of aromatase inhibitors as an alternative to tamoxifen.

Antineoplastic Agents, Hormonal↗