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Biomedical subjects

R Somers

Publications and source records attributed to R Somers.

At least 19 recordsLinked to original sources

Taenia solium taeniasis and cysticercosis in three communities in north Vietnam.

OBJECTIVES: (1) To investigate the response to a serum antigen-detecting ELISA for cysticercosis and a stool coproantigen test for taeniasis in two rural communities (mountainous and coastal areas) and one group of (peri-)urban factory workers; and (2) to examine clinical features of human cysticercosis in northern Vietnam. METHODS: Villagers and factory workers and their families were informed and invited to participate in the study. Blood and faecal samples were collected from the participants and a simple questionnaire on taeniasis/cysticercosis completed. Serum was examined for the presence of circulating cysticercus antigen by a monoclonal-based sandwich ELISA. Ag-ELISA positive persons underwent a clinical examination and a computed tomography (CT) scan. Stool samples were examined microscopically for the presence of Taenia eggs and for copro-antigens. Tapeworms were identified following therapeutic expulsion using morphology and PCR-RFLP. RESULTS: Circulating cysticercus antigens, suggesting active infection, were detected in 5.3% (16/303), 0.6% (1/175) and 0.0% (0/229) of the sampled individuals from the mountainous, coastal and urban regions, respectively. Clinical examination and CT scan of the cysticercus antigen positive persons showed that active cysticercosis did not cause severe disease in most cases. Taenia copro-antigens were found in 0.3% (1/297), 1.8% (3/166) and 0.0% (0/228) of the stool samples from the mountainous, coastal and urban communities, respectively. Three tapeworms were expelled after treatment: two Taenia solium and one Taenia saginata. CONCLUSION: This survey points to a focal distribution of taeniasis/cysticercosis and suggests that human cysticercosis is rather acquired due to close contact with a T. solium carrier and self-infection, than through infection from the environment.

Adolescent↗

Fusion of NUP214 to ABL1 on amplified episomes in T-cell acute lymphoblastic leukemia.

In T-cell acute lymphoblastic leukemia (T-ALL), transcription factors are known to be deregulated by chromosomal translocations, but mutations in protein tyrosine kinases have only rarely been identified. Here we describe the extrachromosomal (episomal) amplification of ABL1 in 5 of 90 (5.6%) individuals with T-ALL, an aberration that is not detectable by conventional cytogenetics. Molecular analyses delineated the amplicon as a 500-kb region from chromosome band 9q34, containing the oncogenes ABL1 and NUP214 (refs. 5,6). We identified a previously undescribed mechanism for activation of tyrosine kinases in cancer: the formation of episomes resulting in a fusion between NUP214 and ABL1. We detected the NUP214-ABL1 transcript in five individuals with the ABL1 amplification, in 5 of 85 (5.8%) additional individuals with T-ALL and in 3 of 22 T-ALL cell lines. The constitutively phosphorylated tyrosine kinase NUP214-ABL1 is sensitive to the tyrosine kinase inhibitor imatinib. The recurrent cryptic NUP214-ABL1 rearrangement is associated with increased HOX expression and deletion of CDKN2A, consistent with a multistep pathogenesis of T-ALL. NUP214-ABL1 expression defines a new subgroup of individuals with T-ALL who could benefit from treatment with imatinib.

Amino Acid Sequence↗

Adult height and age at menarche in childhood cancer survivors.

The aim of this study was to assess the long-term effects of cancer treatments on adult height and age at menarche in survivors of various types of childhood cancer. 285 childhood cancer survivors (161 men and 124 women), at least 18 years old and having been off treatment for at least 5 years, were examined. The effects of cranial (CrRT) and craniospinal irradiation (CrSpRT), other treatments and age at diagnosis on adult height and age at menarche were investigated. Patients who did not receive CrRT or CrSpRT, reached normal adult heights. However, a significant reduction in adult height was observed in men and women treated with CrRT or CrSpRT, especially if the treatment was given at the age of 8 years or younger. In girls, CrRT resulted in a significantly earlier menarche, compared with the Dutch population. Chemotherapy, radiation dose and age at menarche did not affect adult height. The relative risk (RR) of attaining an adult height below the 3rd percentile (20% 49/244) of the study population) was 6 times increased (RR=6.4; 95% confidence interval (CI) 1.46-28.52) after CrSpRT, 4 times (RR=4.2; 95% CI 1.81-9.63) after Crth and 5 times (RR=51; 95% CI 2.23-11.59) when irradiation was administered at the age of 8 years or younger. CrRT and CrSpRT and age at treatment are the main determinants of short stature in male and female childhood cancer survivors.

Adult↗

Cells producing cathepsins D, B, and L in human breast carcinoma and their association with prognosis.

Lysosomal proteinases, cathepsins D, B, and L have been associated with malignant tumor progression and with prognosis in various human carcinomas. In the current study, the immunohistochemical localization of cathepsins in tumor cells was correlated with cathepsin protein concentration in breast carcinoma cytosols from 77 patients. Significant correlation was found for cathepsin D (P < .041) and borderline correlation for cathepsin B (P < .055) but not for cathepsin L. We hypothesize that the poor correlation of cysteine cathepsins was attributable to the fact that they were present not only in malignant epithelial cells, but also in infiltrating macrophages and stromal fibroblasts. In addition, tumor-surrounding myoepithelial cells (42% of tumors) and myofibroblasts (26% of tumors) as well as endothelial cells of neovasculature (10% of tumors) all stained specifically for cathepsin B. Two thirds of tumors co-expressed cathepsins B and L in tumor cells, whereas only 17% of tumors co-expressed all 3 cathepsins. Intense immunostaining for cathepsin D of tumor cells was observed in tumors at high TNM stage and tumors having positive lymph nodes. The expression of cathepsin B was independent of established prognostic factors, whereas intense cathepsin L staining in tumor cells was associated with high histological grade. With respect to prognosis of patient survival, only tumor cell-associated cathepsin D (P = .042) and myoepithelial cell-associated cathepsin B (P = .061) showed borderline significance. Cathepsins B and L immunostaining in tumor cells was not prognostic. In contrast, cytosolic levels of cathepsin B correlated with higher rate of relapse. Taken together, these results show the diversity in the cellular distribution of cathepsins in human breast carcinoma, presumably reflecting specific regulation and function of each of the cathepsins during tumor progression.

Adult↗

Long-term risk of second malignancy in survivors of Hodgkin's disease treated during adolescence or young adulthood.

PURPOSE: To quantify the long-term risk of second primary cancers (SCs) in patients diagnosed with Hodgkin's disease (HD) during adolescence or young adulthood. PATIENTS AND METHODS: The risk of SCs was assessed in 1,253 patients diagnosed with HD before the age of 40 years and treated in two Dutch cancer centers between 1966 and 1986. The median follow-up duration was 14.1 years. RESULTS: In all, 137 patients developed SCs, compared with 19.4 cases expected on the basis of incidence rates in the general population (relative risk [RR] = 7.0; 95% confidence interval, 5.9 to 8.3). The 25-year actuarial risk of SC overall was 27.7%. The RR of solid tumors increased greatly with younger age at the first treatment of HD, not only for breast cancer but also for all other solid tumors, with RRs of 4.9, 6.9, and 12.7 for patients first treated at ages 31 to 39 years, 21 to 30 years, and </= 20 years, respectively. Among patients first treated at the age of 20 years or younger, the RR of developing a solid tumor before the age of 40 years was significantly greater than the RR of solid tumor development at ages 40 to 49 years (RR = 27.9 v RR = 4.2; P =.0001). Patients who received salvage chemotherapy had significantly greater risk of solid cancers other than breast cancer than did patients whose treatment was restricted to initial radiotherapy or initial combined-modality treatment (RR = 9.4 and 4.7, respectively; P =. 004). CONCLUSION: After more than 20 years of follow-up, the risk of solid tumors is still much greater in survivors of HD than in the population at large. Reassuringly, the greatly increased risk of solid tumors in patients who were young (</= 20 years of age) at the first treatment seems to decrease as these patients grow older. Our data suggest that chemotherapy may increase the risk of solid tumors from radiotherapy.

Adolescent↗

Cathepsin B, a prognostic indicator in lymph node-negative breast carcinoma patients: comparison with cathepsin D, cathepsin L, and other clinical indicators.

New prognosticators are needed for breast cancer patients after the initial surgical treatment to make therapeutic decisions that ultimately will affect their DFS. These consist of specific proteolytic enzymes including lysosomal endopeptidases. In this study, the activity and protein concentrations of cathepsins (Cats) D, B, and L were measured in 282 invasive breast tumor cytosols. These potential biological prognostic indicators were compared with other histopathological parameters, such as tumor size, lymph node involvement, tumor-node-metastasis stage, histological grade, DNA analysis, and steroid receptors. CatD protein concentration correlated with lymph node involvement. CatB and CatL levels correlated significantly with Scarf-Bloom-Richardson histological grade and were also higher in estrogen-negative tumors, and CatB was higher in larger tumors. As prognostic markers, CatB concentration was significant for increased risk for recurrence in the entire patient population and specifically also in lymph node-negative patients as follows: high CatB concentration (above 371 micrograms/g) in tumor cytosols was significant (P < 0.00) for high risk of recurrence but was of only borderline prognostic significance (P < 0.06) for overall survival of all patients. In lymph node-negative patients, CatB (above 240 micrograms/g, P < 0.003) was highly significant for recurrence-free survival, followed by CatL (above 20 micrograms/g, P < 0.049) and CatD (above 45 nmol/g, P < 0.044) concentrations. For overall survival of node-negative patients, only CatB was a significant (P < 0.014) prognosticator. We conclude that CatB is useful as a prognostic indicator in lymph node-negative patients. This suggests that selective adjuvant therapy should be applied in this lower risk group of patients when high levels of CatB are determined.

Adult↗

A phase II study of cisplatin, ifosfamide and doxorubicin in operable primary, axial skeletal and metastatic osteosarcoma. European Osteosarcoma Intergroup (EOI).

BACKGROUND: Despite advances in the treatment of primary limb osteosarcoma, the outcome of patients with primary metastatic and axial skeletal disease remains poor. The European Osteosarcoma Intergroup have assessed a combination chemotherapy regimen consisting of ifosfamide (IFOS) 3 g/m2/dl-2, doxorubicin (DOX) 25 mg/m2/dl-3 i.v. bolus and cisplatin (CDDP) 100 mg/m2/dl. PATIENTS AND METHODS: One hundred nine previously untreated patients with primary osteosarcoma were registered. Eligibility was confirmed in 103. At presentation, 45 eligible patients had metastatic disease, 15 axial skeletal primary tumours and 43 non-metastatic limb tumours. RESULTS: The major toxicities were myelosuppression (90%, grade 3 or 4) and nausea and vomiting (74%, grade 3 or 4). Overall mean relative dose intensity (RDI) was 80% (88% CDDP, 75% IFOS, 81% DOX). Clinical response as measured by reduction in tumour volume occurred in 36% (95% confidence interval (95% CI): 27%-47%) of primary tumours. Response of pulmonary metastases to chemotherapy was seen in 33% (95% CI: 19%-49%). Good histological response (> or = 90% necrosis of the tumour) occurred in 33% (95% CI: 22%-45%) of resected tumours. Five-year survival was 62% in limb-non-metastatic, 41% in axial skeletal and 16% in limb metastatic patients. CONCLUSIONS: This regimen is active in osteosarcoma but does not appear to be more active than the two-drug CDDP-DOX regimen currently recommended by EOI.

Adolescent↗

Prognostic factors for the outcome of chemotherapy in advanced soft tissue sarcoma: an analysis of 2,185 patients treated with anthracycline-containing first-line regimens--a European Organization for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group Study.

PURPOSE: A total of 2,185 patients with advanced soft tissue sarcomas who had been treated in seven clinical trials investigating the use of doxorubicin- or epirubicin-containing regimens as first-line chemotherapy were studied in this prognostic-factor analysis. PATIENTS AND METHODS: Overall survival time (median, 51 weeks) and response to chemotherapy (26% complete response or partial response) were the two end points. The cofactors were sex; age; performance status; prior therapies; the presence of locoregional or recurrent disease; lung, liver, and bone metastases at the time of entry onto the trial; long time period between the initial diagnosis of sarcoma and entry onto the study; and histologic type and grade. RESULTS: Univariate analyses showed (a) a significant, favorable influence of good performance status, young age, and absence of liver metastases on both survival time and response rate, (b) a significant, favorable influence of low histopathologic disease grade on survival time, despite a significantly lower response rate, (c) increased survival time for patients with a long time period between the initial diagnosis of sarcoma and entry onto the study, despite equivalent response rates, and (d) increased survival time with liposarcoma or synovial sarcoma, a decreased survival time with malignant fibrous histiocytoma, a lower response rate with leiomyosarcoma, and a higher response rate with liposarcoma (P < .05 for all log-rank and chi2 tests). The Cox model selected good performance status (P < .0001), absence of liver metastases (P = .0001), low histopathologic grade (P = .0002), long time lapse since initial diagnosis (P = .0004), and young age (P = .0045) as favorable prognostic factors of survival time. The logistic model selected absence of liver metastases (P < .0001), young age (P = .0024), high histopathologic grade (P = .0051), and liposarcoma (P = .0065) as favorable prognostic factors of response rate. CONCLUSION: This analysis demonstrates that for advanced soft tissue sarcoma, response to chemotherapy is not predicted by the same factors as is overall survival time. This needs to be taken into account in the interpretation of trials assessing the value of new agents for this disease on the basis of response to treatment.

Adult↗

The International Prognostic Index correlates to survival in patients with aggressive lymphoma in relapse: analysis of the PARMA trial. Parma Group.

The objectives of the present study were to investigate the prognostic value of the International Prognostic Index (IPI) at relapse in the 215 patients with intermediate- or high-grade non-Hodgkin's lymphoma (NHL) included in the PARMA trial. The IPI at relapse was available in 204 (95%) of these patients. Response rates to 2 courses of DHAP were 77%, 54%, 55%, and 42% in patients with an IPI of 0, 1, 2 and 3, respectively (P <.02), whereas complete response (CR) rates were 33%, 29%, 20%, and 0% in the same groups of patients (P <.03). With a median follow-up period of 79 months, overall survival (OS) at 5 years was 46%, 25%, 25%, and 11% in these four groups (P <.001). One hundred nine patients responding to 2 courses of DHAP were randomized to receive either BEAC (carmustine, etoposide, cytarabine, cyclophosphamide and mesna) followed by autologous bone marrow transplantation (ABMT) or 4 additional courses of DHAP: IPI at relapse was found highly correlated to OS in patients treated in the DHAP arm (5-year OS: 48%, 21%, 33%, and 0% for IPI 0, 1, 2, and 3, respectively; P =.006), but not in the BEAC arm (5-year OS: 51%, 47%, 50%, and 50% for IPI 0, 1, 2, and 3, respectively; P =.90). OS was significantly superior in the BEAC arm as compared with the DHAP arm in patients with an IPI >0 (P <.05), but not in patients with an IPI of 0. In conclusion, these results show that IPI correlates to response and overall survival in patients with aggressive NHL in relapse and enables us to identify patients with a significantly different outcome among those treated with conventional chemotherapy alone.

Adolescent↗

[Late sequelae of oncologic treatment in children].

The risk of late effects of cancer treatment in children is higher than that after treatment during adulthood. The late effects of chemotherapy are proportional to the dosage and those of irradiation to the size of the radiation field, fractionation and dose. Irradiation may lead to impaired growth of bone and soft tissues, cranial irradiation to pituitary deficiencies, alopecia and impaired cognitive function, irradiation of the neck to altered thyroid function, thoracic irradiation to diminished pulmonary function and cardiovascular morbidity, radiation therapy of the abdomen to infertility in females, impaired renal function and chronic enteritis. Chemotherapy-induced damage is more organ-specific. Well-known cardiotoxic agents are the anthracycline derivatives. Restricted pulmonary function is seen after treatment with bleomycin and nitrourea derivatives. Several antineoplastic agents are gonadotoxic in men. Nephrotoxic agents are cisplatin and ifosfamide. The cumulative relative risk of developing a second primary neoplasm is 3,8-6,9 after a follow-up period of 25 years. Alkylating agents and the topoisomerase inhibitors are known to increase the risk of haematologic malignancy, while radiation therapy is associated with bone, soft tissue, thyroid, breast, brain and gastrointestinal malignancies.

Adolescent↗

CHOP is the standard regimen in patients > or = 70 years of age with intermediate-grade and high-grade non-Hodgkin's lymphoma: results of a randomized study of the European Organization for Research and Treatment of Cancer Lymphoma Cooperative Study Group.

PURPOSE: We report the results of a randomized study of the European Organization for Research and Treatment of Cancer (EORTC) Lymphoma Group, which compared a chemotherapy regimen specifically devised for elderly patients, ie, etoposide, mitoxantrone, and prednimustine (VMP), versus the standard regimen of cyclophosphamide, doxorobucin, vincristine, and prednisone (CHOP) in patients older than 70 years of age with intermediate- and high-grade non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Patients older than 70 years of age with stage II, III, or IV intermediate- and high-grade NHL, with an Eastern Cooperative Oncology Group (ECOG) performance status less than 4 and acceptable cardiac, renal, and liver function were randomized to receive six courses of VMP or six courses of CHOP. Between February 1989 and June 1994, 130 patients aged 70 to 93 years (median, 75) were enrolled and 120 were assessable for response, 60 patients in each arm. RESULTS: Overall objective response rates were 50% and 77% in VMP- and CHOP-treated patients, respectively (P = .01), while complete response (CR) rates were borderline significant (27% v 45%; P = .06). At 2 years, the progression-free survival (PFS) rate was 25% with VMP versus 55% with CHOP (P = .002) and the overall survival (OS) rate was 30% with VMP versus 65% with CHOP (P = .004). Statistically significant more alopecia and neurologic and gastrointestinal toxicities were reported with CHOP. CONCLUSION: CHOP is the standard regimen for patients > or = 70 years of age with stage II to IV intermediate- and high-grade NHL.

Aged↗

Maintenance of remission with human recombinant interferon alfa-2a in patients with stages III and IV low-grade malignant non-Hodgkin's lymphoma. European Organization for Research and Treatment of Cancer Lymphoma Cooperative Group.

PURPOSE: Interferon alfa has shown significant activity in patients with low-grade malignant non-Hodgkin's lymphoma (NHL). In 1985, we initiated a prospective randomized study in which the potential benefit of interferon alfa given as maintenance treatment was investigated after tumor load reduction was achieved with chemoradiotherapy in patients with advanced low-grade malignant non-Hodgkin's lymphoma. PATIENTS AND METHODS: The study involved 347 patients with stage III or IV disease, 315 satisfying the eligibility criteria. All were treated with a regimen of cyclophosphamide, vincristine, and prednisone (CVP) given every 3 weeks for eight cycles. Thereafter, patients were eligible for iceberg irradiation. Finally, all patients were completely restaged, and responding and stable-disease patients were then randomized, 122 to interferon alfa-2a maintenance, 3 million U three times weekly for 1 year; and 120 to no further treatment. RESULTS: Seventy-nine percent of the patients response to CVP, ie, 45% complete remissions (CR) and 34% partial remissions (PR). In the group of randomized patients, the response rate after CVP plus or minus radiotherapy was 90%. As compared with control patients, patients in the interferon (IFN) maintenance group had a tendency toward a prolonged time to progression (TTP) (median, 132 v 87 weeks; P = .054, adjusted for response to CVP). However, overall survival was similar in both groups. Interferon was well tolerated. The median dose of IFN actually received corresponded to 90% of the planned cumulative dose. The treatment had to be stopped because of toxicity in 16 patients (15% of the patients in whom IFN was started). CONCLUSION: Interferon maintenance treatment in the phase of minimal residual disease of patients with advanced low-grade malignant NHL increased TTP at the borderline of statistical significance, without remarkable toxicity. However, overall survival was not influenced.

Adult↗

Time to relapse has prognostic value in patients with aggressive lymphoma enrolled onto the Parma trial.

PURPOSE: The purpose of this study was to investigate the prognostic value of time to relapse in 188 adult patients with intermediate- or high-grade non-Hodgkin's lymphoma (NHL) included on the Parma trial at the time of their first relapse. PATIENTS AND METHODS: The median follow-up of these patients is 102 months after registration onto the Parma study. Time to relapse was calculated from initial diagnosis, and a cutoff of 12 months was used to separate 77 patients defined as early relapse from 111 patients defined as late relapse. RESULTS: Patients with early and late relapses had significantly different overall response rates to salvage therapy with two courses of dexamethasone, high-dose cytarabine, and cisplatin (DHAP; 40% v 69%; P=.00007) and different 8-year survival rates (13% v 29%; P=.00001). Features at relapse with a negative prognostic value in univariate analysis were higher than normal lactic dehydrogenase (LDH) levels, tumor size greater than 5 cm, Ann Arbor stages III to IV, and Karnofsky score less than 80%. Therefore, multivariate analyses were performed. Time to relapse (P=.001) and LDH levels at relapse (P=.003) had independent prognostic value, whereas tumor size did not reach statistical significance in the logistic model that predicted overall response after two courses of DHAP. The study of prognostic factors for overall survival (OS) and progression-free survival (PFS) confirmed the prognostic value of time to relapse (P < .0001 for OS and P=.005 for PFS) independent of response or treatment after two courses of DHAP. CONCLUSION: Time to relapse may be used to stratify patients at time of first relapse of intermediate to high-grade non-Hodgkin's lymphoma.

Adult↗

Persistent improved results after adding vincristine and bleomycin to a cyclophosphamide/hydroxorubicin/Vm-26/prednisone combination (CHVmP) in stage III-IV intermediate- and high-grade non-Hodgkin's lymphoma. The EORTC Lymphoma Cooperative Group.

CHOP has been and still is regarded by many as the 'standard' treatment of advanced non-Hodgkin's lymphoma. In 1980 the EORTC Lymphoma Cooperative Group started a study to evaluate the addition of vincristine and bleomycin to its standard four-drug combination chemotherapy, CHVmP (cyclophosphamide, hydroxorubicin, Vm-26, prednisone). Eligible patients were stage III or IV, intermediate- to high-grade non-Hodgkin's lymphoma (Working Formulation E-I). One-hundred-eighty-nine patients were entered, of whom 140 were eligible and evaluable. A previous report showed an improved response rate and failure-free survival (FFS) and overall survival for the combination CHVmP-VB. At ten years, the outcome still favors the addition of vincristine and bleomycin. The FFS was 34% vs. 23% and the overall survival 34% vs 22%. This difference was mainly due to a difference in CR rate (74% vs. 49%), Relapse-free survival for patients reaching a CR was the same in both arms. When the patients were grouped according to the International Prognostic Factor Index, no statistically significant difference could be observed in favor of one treatment within either group. This trial clearly demonstrates the benefit gained by the addition of vincristine and bleomycin to 'standard' chemotherapy for intermediate and high-grade non-Hodgkin's lymphoma.

Adolescent↗

Clinical analysis of 670 cases in two trials of the European Organization for the Research and Treatment of Cancer Lymphoma Cooperative Group subtyped according to the Revised European-American Classification of Lymphoid Neoplasms: a comparison with the Working Formulation.

In the Working Formulation (WF), non-Hodgkin's lymphomas (NHL) are grouped according to their clinical behavior. These disorders are listed as entities defined by morphology, phenotype, and cytogenetics in the proposed Revised European-American Classification of Lymphoid Neoplasms (REAL), the clinical relevance of which is still debated. We analyzed 670 NHL cases included in two randomized clinical trials (EORTC 20855 WF-intermediate/high-grade and 20856 WF-low-grade malignancy) with histologic material available for review. Based on hematoxylin-eosin-stained sections, 77% of cases could be subtyped. Immunophenotyping was considered to be mandatory only in diagnosing T-cell lymphoma and anaplastic large-cell lymphoma. Of 522 cases subtyped, 11% were mantle cell lymphoma (MCL), 5% were marginal zone B-cell lymphoma (MZBCL), 46% were follicle center lymphoma, and 32% were diffuse large B-cell lymphoma. Statistical analysis and comparisons between classifications were made only within each trial and treatment group. MCL and MZBCL were characterized by a shorter median survival (3.4 and 4.1 years, respectively) in comparison with low- and intermediate-grade WF groups (> 9.3 and 5.8 years, respectively). In terms of progression-free survival, MCL showed a behavior similar to the low-grade group, with frequent relapses. Follicle center cell lymphomas behaved as low-grade lymphomas as defined by the WF and diffuse large B-cell lymphomas as the WF-intermediate grade group. Because several NHL entities have a clinical behavior of their own, their recognition by the REAL classification offers clinicians additional information that is not obtained when the WF is used.

Antineoplastic Combined Chemotherapy Protocols↗

Cathepsins D, B, and L in transformed human breast epithelial cells.

To investigate the regulation of lysosomal enzymes during carcinogenesis, we measured cathepsins (Cats) D, B, and L in MCF-10F, which is a human breast epithelial cell line, and cells evolved after treatment with carcinogen and transfected with c-Ha-ras oncogene. The clones used in this study, MCF-10FTras, D3, D3-1, and D3-1Tras, expressed no estrogen receptors and gradually increased invasive potential, while oncogene-transfected lines were also tumorigenic in SCID mice [16, 19]. Cats D, B, and L were determined in the cells and in cell media using enzyme-linked immunosorbent assay (ELISA), specific enzyme activity measurements, and immunocytochemistry. The major intra- and extracellular lysosomal proteinase in these cells was Cat D (30-180 pm/mg), followed by Cat B (2-10 pm/mg) and Cat L (1-5 pm/mg). An inverse relationship between intracellular Cat D levels and invasive potential of carcinogen-treated and c-Ha-ras oncogene-transfected cell lines was observed. No significant changes in extracellular concentration of Cat D precursor in this series of cell lines was observed. Intracellular levels of Cats B and L were unchanged or slightly lower in carcinogen-treated D3 and D3-1 cells, as well as in MCF-10FTras. On the other hand, in D3-1Tras cell line, evolving from c-Ha-ras transfected D3-1 line, 3.5 fold and 4.4 fold increases in Cat B and Cat L, respectively, but a 2 fold decrease in Cat D, were observed compared to the parental cell line. Immunocytochemical staining showed a granular, polarized perinuclear and cytoplasmic staining of cathepsins in all cell lines. Cysteine proteinases stained more frequently and more intensely in D3-1Tras compared to other lines, confirming the immunochemical assays. We hypothesize that several molecular events, caused by a carcinogen and an oncogene such as c-Ha-ras, are needed to increase Cat B and Cat L, but not Cat D, expression. Therefore, the cysteine and aspartic lysosomal proteinases are differentially expressed in the breast cell lines with more invasive phenotype.

Breast↗