Diffuse large B-cell lymphoma in Southeast Asian cohort: expression patterns of B-cell receptor (BCR) repertoire and its linkage with molecular subtypes and response to R-CHOP therapy

AIMS

Heightened B-cell receptor (BCR) activity in diffuse large B-cell lymphoma (DLBCL) is well established, and a subset of patients with relapsed DLBCL can benefit from BCR-targeted therapies. Universal outreach of such emerging therapies mandates forming a global landscape of BCR molecular signalling in DLBCL, including Southeast Asia.

METHODS

79 patients with DLBCL (nodal, 59% and extranodal, 41%) treated with rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) therapy were selected. Expression levels of BCR and linked signalling pathway molecules were inter-related with Lymph2Cx-based cell of origin (COO) types and overall survival (OS).

RESULTS

Activated B-cell (ABC) type DLBCL constituted 49% (39/79) compared with germinal centre B-cell (GCB) type DLBCL (29/79; 37%) and revealed poor prognosis (p=0.013). In ABC-DLBCL, high BTK expression exerted poor response to R-CHOP, while OS in ABC-DLBCL with low BTK expression was similar to GCB-DLBCL subtype (p=0.004). High LYN expression coupled with a poor OS for ABC-DLBCL as well as GCB-DLBCL subtypes (p=0.001). Furthermore, high coexpression of BTK/LYN (BTK ^high/LYN ^high) showed poor OS (p=0.019), which linked with upregulation of several genes associated with BCR repertoire and nuclear factor-kappa B pathway (p<0.01). In multivariate analysis, high BTK and LYN expression retained prognostic significance against established clinical predictive factors such as age, International Prognostic Index and COO (p<0.05).

CONCLUSIONS

Our data provide a clear association between high BCR activity in DLBCL and response to therapy in a distinct population. Molecular data provided here will pave the pathway for the provision of promising novel-targeted therapies to patients with DLBCL in Southeast Asia.

Expression of the Class II and III Beta-Tubulin in Neoplastic and Non-Neoplastic Lymphoid Tissues

Aim: Abnormal expression patterns of beta-tubulin isotypes may provide a molecular rationale for the behaviour of lymphoma subtypes. In the present study class II and III beta-tubulin expression was assessed in non-neoplastic and neoplastic lymphoid tissues with reference to potential utility as new tumour biomarkers. Methods and results: In this cross-sectional study class II and III beta-tubulin expression was assessed in 304 neoplastic and 20 normal lymphoid tissues using qualitative and semi-quantitative immunohistochemistry. Class II beta-tubulin was found to be positive in the germinal centres, mantle zone and interfollicular regions of normal lymphoid tissues. It was also expressed in 15/15 (100%) lymphoblastic lymphomas, 229/231 (99%) mature B cell lymphomas, 22/22 (100%) T/NK-cell lymphomas and 36/36(100%) classical Hodgkin lymphomas. Class III beta-tubulin in contrast was germinal centre restricted and more selective, being found mainly in classical Hodgkin lymphomas (34/36 (94%)). It was also expressed in 58/171(34%) DLBCL, 11/12 (92%) mantle cell lymphomas and 6/6 (100%) Burkitt lymphomas. Other mature B cell, T/NK cell lymphomas and precursor lymphoblastic lymphomas were usually negative. Conclusions: Class II beta-tubulin shows ubiquitous expression in neoplastic and non-neoplastic lymphoisd tissues. In contrast, Class III beta-tubulin is germinal centre-restricted. Its consistent expression in classical Hodgkin lymphomas may point to use in the identification of Reed-Sternberg and Hodgkin cells. Its expression in a proportion of DLBCL, Burkitt and mantle cell lymphomas is of interest as this may be related to their aggressiveness.

The impact of HMOs on hospital-based uncompensated care

Managed care in general and HMOs in particular have become the vehicle of choice for controlling health care spending in the private sector. By several accounts, managed care has achieved its cost-containment objectives. At the same time, the percentage of Americans without health insurance coverage continues to rise. For-profit and not-for-profit hospitals have traditionally financed care for the uninsured from profits derived from patients with insurance. Thus the relationship between growth in managed care and HMOs, hospital "profits," and care for the uninsured represent an important policy question. Using national data over an eight-year period, we find that a ten-percentage point increase in managed care penetration is associated with a two-percentage point reduction in hospital total profit margin and a 0.6 percentage point decrease in uncompensated care.

Market incentives, plan choice, and price increases

The Federal Employees Health Benefits Program (FEHBP) has attracted considerable interest for its ability to control health care costs. We examine the impact of the FEHBP's maximum dollar contribution on incentives to select low-cost plans and the growth in insurance premiums over time. Unless the maximum dollar contribution is pegged to a low-price plan, few enrollees select such plans. Moreover, premiums rise at least five percentage points per year faster among plans below this fixed subsidy level than they do in plans above it. Our results have important implications for the design of similar market-based approaches.

Covering uninsured children and their parents: estimated costs and number of newly insured

The Child Health Insurance Program (CHIP) supplies $20.4 billion over 5 years and nearly $50 billion over 10 years to extend health insurance to uninsured children with family incomes up to 200 percent of poverty. This article analyzes the March 1997 Current Population Survey, estimating the number of children likely to be eligible for CHIP or currently eligible for Medicaid. Of the 8.6 million parents of uninsured children, four out of five were uninsured at the time of the survey. Expanding coverage to parents as well as children could make program participation more attractive and simplify the enrollment process. If 75 percent of uninsured parents of CHIP eligible children participated, 1.7 million parents could be insured, costing federal and state governments $4 billion. Another 3.4 million parents would be insured by expanding Medicaid to cover uninsured parents of Medicaid-eligible children.

The Impact of the Family Planning Supply Environment on Contraceptive Intentions and Use in Morocco

Although the extent to which organized family planning programs influence reproductive preferences remains a subject of debate, most observers would grant that such programs play a key role in helping individuals to realize their contraceptive and reproductive intentions. However, few prior studies have quantified the magnitude of this facilitating or enabling effect of family planning services, given existing demand for contraception. This study takes advantage of panel survey data and linked information on the supply environment for family planning services in Morocco in order to bridge this research gap. In the analysis, contraceptive use during the 1992-95 period is related to contraceptive intentions in 1992; individual-, household-, and community-level determinants of contraceptive behavior; and family planning supply factors. Estimation procedures are used that control for unobserved joint determinants of contraceptive intentions and use. Evidence of a significant enabling or facilitating role of family planning services is found, and the results also suggest that family planning program factors influence contraceptive intentions in important ways.

Why are workers uninsured? Employer-sponsored health insurance in 1997

This study examines the number of workers in firms offering employee health plans, the number of workers eligible for such plans, and participation in employer-sponsored insurance. Data from the February 1997 Contingent Worker Supplement to the Current Population Survey indicate that 10.1 million workers are employed by firms offering insurance but are not eligible. Not all of these workers are eligible for coverage, most often because of hours of work. Our results indicate that 11.4 million workers rejected coverage when it was offered. Of those, 2.5 million workers were uninsured. Workers cited high cost of insurance most often as the primary factor for refusing coverage.

Health insurance among children: the role of expanded Medicaid coverage

This study uses data from the National Longitudinal Survey of Youth to track the health coverage of parents in the year before and the year in which their children enroll in Medicaid. Use of such longitudinal data, compared to cross-sectional data, provides more insight into the dynamics of health insurance coverage and expansions in Medicaid. Using these data, we find that approximately 16% of newly enrolled Medicaid children likely had access to private insurance through a parent. Moreover, most of the children enrolling in Medicaid were previously uninsured. We find little substitution of private for public health insurance among families living at or near the federal poverty line.