Prospective Statewide Study of Universal Screening for Hereditary Colorectal Cancer: The Ohio Colorectal Cancer Prevention Initiative.

Hereditary cancer syndromes infer high cancer risks and require intensive surveillance. Identification of high-risk individuals among patients with colorectal cancer (CRC) needs improvement. METHODS: Three thousand three hundred ten unselected adults who underwent surgical resection for primary invasive CRC were prospectively accrued from 51 hospitals across Ohio between January 1, 2013, and December 31, 2016. Universal Tumor screening (UTS) for mismatch repair (MMR) deficiency was performed for all, and pathogenic germline variants (PGVs) were identified using multigene panel testing (MGPT) in those who met at least one inclusion criterion: MMR deficiency, diagnosed < 50 years, multiple primary tumors (CRC or endometrial cancer), or with a first-degree relative with CRC or endometrial cancer. RESULTS: Five hundred twenty-five patients (15.9%) had MMR deficiency. Two hundred thirty-four of 3,310 (7.1%; 16% of the 1,462 who received MGPT) had 248 PGVs in cancer susceptibility genes. One hundred forty-two (4.3%) had a PGV in an MMR gene, and 101 (3.1%) had a PGV in a non-MMR gene. Ten with Lynch syndrome (LS) also had a non-MMR PGV and were included in both groups. Two (0.06%) had constitutional MLH1 hypermethylation. Of unexplained MMR-deficient patients, 88.4% (76 of 86) had double somatic MMR mutations. Testing for only MMR genes in MMR-deficient patients would have missed 18 non-MMR gene PGVs (7.3% of total PGVs identified). Had UTS been the only method used to screen for hereditary cancer syndromes, 38.6% (91 of 236) would have been missed, including 6.3% (9 of 144) of those with LS. These results have treatment implications as 5.3% (175 of 3,310) had PGVs in genes with therapeutic targets. CONCLUSION: UTS alone is insufficient for identifying a large proportion of CRC patients with hereditary syndromes, including some with LS. At a minimum, 7.1% of individuals with CRC have a PGV and pan-cancer MGPT should be considered for all patients with CRC.

Differential effects of IL-2 and IL-21 on expansion of the CD4+ CD25+ Foxp3+ T regulatory cells with redundant roles in natural killer cell mediated antibody dependent cellular cytotoxicity in chronic lymphocytic leukemia.

CD4(+) CD25(+) regulatory T cells are expanded in solid and hematological malignancies including chronic lymphocytic leukemia (CLL). Several cytokines and co-stimulatory molecules are required for generation, survival and maintenance of their suppressive effect. We and others have shown direct cytotoxic effect of the novel common gamma chain cytokine interleukin (IL)-21 on primary B cells from CLL patients. Since members of this family of cytokines are known to exhibit their effects on diverse immune cells, we have examined the effects of IL-21 on CLL patient derived regulatory T cell (Treg) induction, expansion and the inhibitory effect on natural killer cells in vitro. We demonstrate here the expression of IL-21 receptor in CD4(+)CD25(High) regulatory cells from CLL patients. In contrast to IL-2, the IL-21 cytokine failed to mediate expansion of regulatory T cells or induced expression of Foxp3 in CD4(+)CD25(Intermediate) or CD4(+)CD25(Dim/-) T cells in whole blood derived from CLL patients. Interestingly, in contrast to their differential effects on expansion of the CD4(+)CD25(+)Foxp3(+)T cells, IL-2 and IL-21 exhibited a redundant role in Treg mediated suppression of NK cell mediated antibody dependent cytotoxicity function. Given the infusion related toxicities and pro-survival effect of IL-2 in CLL, these studies provide a rationale to explore IL-21 as an alternate gamma chain cytokine in CLL therapy.

The humanized CD40 antibody SGN-40 demonstrates pre-clinical activity that is enhanced by lenalidomide in chronic lymphocytic leukaemia.

Antibody-based therapies, such as rituximab and alemtuzumab, have contributed significantly to the treatment of Chronic Lymphocytic leukaemia (CLL). The CD40 antigen is expressed predominantly on B-cells and represents a potential target for immune-based therapies. SGN-40 is a humanized IgG1 monoclonal antibody currently in Phase I/II clinical trials for indolent lymphomas, diffuse large B cell lymphomas and Multiple Myeloma. Its biological effect on CLL cells has not been studied. The present study demonstrated that SGN-40 mediated modest apoptosis in a subset of patients with secondary cross-linking but did not mediate complement-dependent cytotoxicity. SGN-40 also mediated antibody-dependent cellular cytotoxicity (ADCC) predominantly through natural killer (NK) cells. Previous studies by our group and others have demonstrated that lenalidomide upregulates CD40 expression on primary B CLL cells and activates NK-cells. We therefore examined for the combinatorial effect of lenalidomide and SGN-40 and demonstrated that both enhanced direct apoptosis and ADCC against primary CLL B cells. These data together provide justification for clinical trials of SGN-40 and lenalidomide in combination for CLL therapy.

Acquirement of rituximab resistance in lymphoma cell lines is associated with both global CD20 gene and protein down-regulation regulated at the pretranscriptional and posttranscriptional levels.

Acquirement of resistance to rituximab has been observed in lymphoma patients. To define mechanisms associated with rituximab resistance, we developed various rituximab-resistant cell lines (RRCL) and studied changes in CD20 expression/structure, lipid raft domain (LRD) reorganization, calcium mobilization, antibody-dependent cellular cytotoxicity, and complement-mediated cytotoxicity (CMC) between parental and RRCL. Significant changes in surface CD20 antigen expression were shown in RRCL. Decreased calcium mobilization and redistribution of CD20 into LRD were found in RRCL. Western blotting identified a unique 35 kDa protein band in RRCL, which was not seen in parental cells and was secondary to an increase in surface and cytoplasmic expression of IgM light chains. CD20 gene expression was decreased in RRCL. In vitro exposure to PS341 increased CD20 expression in RRCL and minimally improved the sensitivity to rituximab-associated CMC. Our data strongly suggest that the acquisition of rituximab resistance is associated with global gene and protein down-regulation of the CD20 antigen affecting LRD organization and downstream signaling. CD20 expression seems to be regulated at the pretranscriptional and posttranscriptional levels. Proteasome inhibition partially reversed rituximab resistance, suggesting the existence of additional mediators of rituximab resistance. Future research is geared to identify drugs and/or biological agents that are effective against RRCL.

IL-21 mediates apoptosis through up-regulation of the BH3 family member BIM and enhances both direct and antibody-dependent cellular cytotoxicity in primary chronic lymphocytic leukemia cells in vitro.

Interleukin-21 (IL-21) is a recently identified gamma-chain receptor cytokine family member that promotes B-cell apoptosis as well as activation of innate immune system. Based on this, we hypothesized that IL-21 might enhance the apoptosis induced by fludarabine and rituximab and also play a role in augmenting immune-mediated clearance of the chronic lymphocytic leukemia (CLL) cells. Our studies demonstrate that the majority of CLL patients have surface IL-21 receptor-alpha, and its expression correlates with apoptosis, tyrosine phosphorylation of STAT1, and up-regulation of the proapoptotic BH3 domain protein BIM. IL-21-induced BIM up-regulation is critical for apoptosis because inhibition of BIM expression using small interfering RNA prevented IL-21-induced apoptosis. IL-21 treatment of CLL cells but not normal T cells with fludarabine or rituximab additively enhanced the direct cytotoxic effect of these therapies. In addition to its proapoptotic effect, IL-21 promoted STAT1 and STAT5 phosphorylation in natural killer cells with concurrent enhanced antibody-dependent cellular cytotoxicity against rituximab-coated CLL cells in vitro. These data provide justification for combination studies of IL-21 with fludarabine and rituximab in CLL and suggest that BIM up-regulation might serve as relevant pharmacodynamic end point to measure biologic effect of this cytokine in vivo.

Targeting CD37-positive lymphoid malignancies with a novel engineered small modular immunopharmaceutical.

CD37 is a lineage-specific B-cell antigen that to date has been neglected as an attractive therapeutic target. To exploit this, novel CD37-specific small modular immunopharmaceuticals (CD37-SMIP) that include variable regions linked to modified human IgG(1) hinge, CH(2), and CH(3) domains were designed. The lead CD37-SMIP molecule induces potent apoptosis in the presence of a cross-linker, and antibody-dependent cellular cytotoxicity against B-cell leukemia/lymphoma cell lines and primary chronic lymphocytic leukemia (CLL) cells superior to therapeutic antibodies used in these diseases. The CD37-SMIP-dependent ADCC function in vitro was mediated by natural killer (NK) cells but not naive or activated monocytes. Significant in vivo therapeutic efficacy was demonstrated in a SCID mouse xenograft leukemia/lymphoma model. Depletion of NK cells in this mouse model resulted in diminished efficacy further supported the in vivo importance of NK cells in SMIP therapy. These findings provide strong justification for CD37 as a therapeutic target and introduce small modular immunopharmaceuticals as a novel class of targeted therapies for B-cell malignancies.

Use of prognostic factors in risk stratification at diagnosis and time of treatment of patients with chronic lymphocytic leukemia.

PURPOSE OF REVIEW: To review risk stratification strategies used in chronic lymphocytic leukemia at diagnosis to predict aggressiveness of disease and, at time of treatment, to predict duration of response. RECENT FINDINGS: Several new prognostic factors can better assist clinicians in predicting the aggressiveness of chronic lymphocytic leukemia at diagnosis and the likelihood of maintaining a prolonged remission with treatment. This article reviews older prognostic factors such as beta2-microglobulin and thymidine kinase activity that have been partially validated by recently completed large studies. New prognostic factors such as interphase cytogenetics, immunoglobulin heavy-chain gene mutational analysis, and relevant secondary surrogate markers of immunoglobulin heavy-chain gene, including methylation of the zeta-associated protein gene, lipoprotein lipase overexpression, telomere length, and telomerase activity are reviewed. Some prognostic factors (interphase cytogenetics) but not others (immunoglobulin heavy-chain gene mutational status, zeta-associated protein expression) predict the duration of response to fludarabine-based combination strategies. SUMMARY: Recent advances in risk stratification provide clinicians with tools to better predict outcome of chronic lymphocytic leukemia at the time of treatment and response to treatment at the time of developing symptomatic disease.

Hypersensitivity Reactions to oxaliplatin: incidence and management.

Oxaliplatin (Eloxatin) is a novel platinum compound that has activity in a wide variety of tumors. Several hypersensitivity reactions distinct from laryngopharyngeal dysesthesia have been described. We retrospectively analyzed 169 consecutive patients who received oxaliplatin for esophageal or colorectal cancer between 1/1/00 and 7/31/02 and reviewed any significant adverse reactions labeled as hypersensitivity reactions. Thirty-two patients (19%) reportedly experienced hypersensitivity. Skin rash was the most common event (22 patients), occurring after a median of three infusions. Fever was seen in five patients after a median of two infusions. Five patients experienced respiratory symptoms at median infusion number 6. Ocular symptoms of lacrimation and blurring of vision were seen in two patients. Five patients experienced more than one type of reaction. Treatments prescribed for hypersensitivity were antihistamines, steroids, and topical emollients. One patient developed grade 4 hypersensitivity during cycle 6, characterized by laryngeal edema, tongue swelling, and labored breathing. This patient underwent a desensitization procedure, adapted from guidelines for carboplatin (Paraplatin) allergy. Subsequently, three cycles were administered over 6 hours and were well tolerated. However, during the fourth infusion postdesensitization, the patient developed recurrent signs of hypersensitivity. In conclusion, hypersensitivity is frequently seen with oxaliplatin, but most reactions are mild.

Development of targeted therapies for B-cell non-Hodgkin lymphoma and multiple myeloma.

The design of innovative, more effective, and less toxic therapy of B-cell lymphoma is emerging in parallel to a better understanding of the mechanisms of action of target-specific agents targeting the neoplastic B cell. Rituximab has changed the treatment paradigm of patients with B-cell lymphomas and is considered the first effective targeted therapy approved by the US Food and Drug Administration (FDA) for the treatment of lymphoproliferative disorders. Despite its good efficacy and safety profile, sustained complete remissions have been documented in a relatively small proportion of patients treated with rituximab monotherapy. To improve antitumor activity, initial strategies combined rituximab with standard chemotherapy drugs which led to higher response rates and improvement in disease-free and in some cases (ie, diffuse large B-cell lymphoma) prolongation of overall survival. While rituximab has been incorporated into multiple chemotherapy regimens (ie, CVP, CHOP, FND, etc.) a significant number of lymphoma patients either relapse after initial responses or fail to respond as a consequence of either intrinsic or acquired resistance. Scientific efforts are being focused toward developing new strategies to improve rituximab activity. In this report we provide an overview of recent developments in target-specific therapies and review past, ongoing, and future research tiling this diverse group of exciting novel agents.