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In November 2013, ibrutinib was approved by the US FDA for treating MCL.
Other targeted agents include the proteasome inhibitor bortezomib, mTOR inhibitors such as temsirolimus, and the P110δ inhibitor GS-1101.
Chemotherapy is widely used as frontline treatment, and often is not repeated in relapse due to side effects. Alternate chemotherapy is sometimes used at first relapse. For frontline treatment, CHOP with rituximab is the most common chemotherapy, and often given as outpatient by IV. A stronger chemotherapy with greater side effects (mostly hematologic) is HyperCVAD, often given as in-patient, with rituximab and generally to fitter patients (some of which are over 65). HyperCVAD is becoming popular and showing promising results, especially with rituximab. It can be used on some elderly (over 65) patients, but seems only beneficial when the baseline Beta-2-MG blood test was normal. It is showing better complete remissions (CR) and progression free survival (PFS) than CHOP regimens. A less intensive option is bendamustine with rituximab.
Second line treatment may include fludarabine, combined with cyclophosphamide and/or mitoxantrone, usually with rituximab. Cladribine and clofarabine are two other drugs being investigated in MCL. A relatively new regimen that uses old drugs is PEP-C, which includes relatively small, daily doses of prednisone, etoposide, procarbazine, and cyclophosphamide, taken orally, has proven effective for relapsed patients. According to John Leonard, PEP-C may have anti-angiogenetic properties, something that he and his colleagues are testing through an ongoing drug trial.
Another approach involves using very high doses of chemotherapy, sometimes combined with total body irradiation (TBI), in an attempt to destroy all evidence of the disease. The downside to this is the destruction of the patients' entire immune system as well, requiring rescue by transplantation of a new immune system (hematopoietic stem cell transplantation), using either autologous stem cell transplantation, or those from a matched donor (an allogeneic stem cell transplant). A presentation at the December 2007 American Society of Hematology (ASH) conference by Christian Geisler, chairman of the Nordic Lymphoma Group claimed that according to trial results, mantle cell lymphoma is potentially curable with very intensive chemo-immunotherapy followed by a stem cell transplant, when treated upon first presentation of the disease.
These results seem to be confirmed by a large trial of the European Mantle Cell Lymphoma Network indicating that induction regimens containing monoclonal antibodies and high dose ARA-C (Cytarabine) followed by ASCT should become the new standard of care of MCL patients up to approximately 65 years.
A study released in April 2013 showed that patients with previously untreated indolent lymphoma, bendamustine plus rituximab can be considered as a preferred first-line treatment approach to R-CHOP because of increased progression-free survival and fewer toxic effects.
Targeted therapy attacks cancer cells at a specific target, with the aim of not harming normal cells.
- Alemtuzumab is a mAb directed against CD52 used in CLL.
- Rituximab, ofatumumab, and obinutuzumab are antibodies against CD20 used to treat CLL.
- Ibrutinib, a Bruton's tyrosine kinase (BTK) inhibitor, is used to treat CLL.
- Idelalisib is a PI3K inhibitor. and is taken orally.
- Venetoclax is a Bcl-2 inhibitor used to treat people with CLL who have 17p deletion (deletion located on the chromosome 17 short arm) and who have been treated with at least one prior therapy.
Current treatment typically includes R-CHOP, which consists of the traditional CHOP, to which rituximab has been added. This regimen has increased the rate of complete response for DLBCL patients, particularly in elderly patients.R-CHOP is a combination of one monoclonal antibody (rituximab), three chemotherapy agents (cyclophosphamide, doxorubicin, vincristine), and one steroid (prednisone). These drugs are administered intravenously, and the regimen is most effective when it is administered multiple times over a period of months. People often receive this type of chemotherapy through a PICC line (peripherally inserted central catheter) in their arm near the elbow or a surgically implanted venous access port. The number of cycles of chemotherapy given depends on the stage of the disease — patients with limited disease typically receive three cycles of chemotherapy, while patients with extensive disease may need to undergo six to eight cycles. A recent approach involves obtaining a PET scan after the completion of two cycles of chemotherapy, to assist the treatment team in making further decisions about the future course of treatment.Older people often have more difficulty tolerating therapy than younger people. Lower intensity regimens have been attempted in this age group.
Radiation therapy is often part of the treatment for DLBCL. It is commonly used after the completion of chemotherapy. Radiation therapy alone is not an effective treatment for this disease.
Combination chemotherapy regimens are effective in both newly diagnosed and relapsed CLL. Combinations of fludarabine with alkylating agents (cyclophosphamide) produce higher response rates and a longer progression-free survival than single agents:
- FC (fludarabine with cyclophosphamide)
- FR (fludarabine with rituximab)
- FCR (fludarabine, cyclophosphamide, and rituximab)
- CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone)
Although the purine analogue fludarabine was shown to give superior response rates to chlorambucil as primary therapy, no evidence shows early use of fludarabine improves overall survival, and some clinicians prefer to reserve fludarabine for relapsed disease.
Chemoimmunotherapy with FCR has shown to improve response rates, progression-free survival, and overall survival in a large randomized trial in CLL patients selected for good physical fitness. This has been the first clinical trial demonstrating that the choice of a first-line therapy can improve the overall survival of patients with CLL.
Alkylating agents approved for CLL include bendamustine and cyclophosphamide.
Selection of biological targets on the basis of their combinatorial effects on the leukemic lymphoblasts can lead to clinical trials for improvement in the effects of ALL treatment. Tyrosine-kinase inhibitors (TKIs), such as Imatinib, are often incorporated into the treatment plan for patients with "Bcr-Abl1+ (Ph+)" ALL. However, this subtype of ALL is frequently resistant to the combination of chemotherapy and TKIs and allogeneic stem cell transplantation is often recommended upon relapse.
Blinatumomab, a CD19-CD3 bi-specific monoclonal murine antibody, currently shows promise as a novel pharmacotherapy. By engaging the CD3 T-cell with the CD19 receptor on B cells, it triggers a response to induce the release of inflammatory cytokines, cytotoxic proteins and proliferation of T cells to kill CD19 B cells.
Typically, people who experience a relapse in their ALL after initial treatment have a poorer prognosis than those who remain in complete remission after induction therapy. It is unlikely that the recurrent leukemia will respond favorably to the standard chemotherapy regimen that was initially implemented, and instead these patients should be trialed on reinduction chemotherapy followed by allogeniec bone marrow transplantation. These patients in relapse may also receive blinatumomab, as it has shown to increase remission rates and overall survival rates, without increased toxic effects.
Low dose palliative radiation may also help reduce the burden of tumor inside or outside the central nervous system and alleviate some symptoms.
Recently, there has also been evidence and approval of use for dasatinib, a tyrosine kinase inhibitor. It has shown efficacy in cases of patients with Ph1-positive and imatinib-resistant ALL, but more research needs to be done on long term survival and time to relapse.
In general, the first line of treatment for Burkitt’s lymphoma is intensive chemotherapy. A few of these regimens are: the GMALL-B-ALL/NHL2002 protocol, the modified Magrath regimen (R-CODOX-M/IVAC). COPADM, hyper-CVAD, and the Cancer and Leukemia Group B (CALGB) 8811 regimen; these can be associated with rituximab. In older patients treatment may be dose-adjusted EPOCH with rituximab.
The effects of the chemotherapy, as with all cancers, depend on the time of diagnosis. With faster-growing cancers, such as Burkitt's, the cancer actually responds faster than with slower-growing cancers. This rapid response to chemotherapy can be hazardous to the patient, as a phenomenon called "tumor lysis syndrome" could occur. Close monitoring of the patient and adequate hydration is essential during the process. Since Burkitts lymphoma has high propensity to spread to the central nervous system (lymphomatous meningitis), intrathecal chemotherapy with methotrexate and/or ARA-C and/or prednisolone is given alongside with systemic chemotherapy.
Chemotherapy
- cyclophosphamide
- doxorubicin
- vincristine
- methotrexate
- cytarabine
- ifosfamide
- etoposide
- rituximab
Other treatments for Burkitt's lymphoma include immunotherapy, bone marrow transplants, stem cell transplant, surgery to remove the tumor, and radiotherapy.
mTOR inhibitors :
- Everolimus
- Temsirolimus
mTOR is a kinase enzyme inside the cell that regulates cell growth, proliferation, and survival. mTOR inhibitors lead to cell cycle arrest in the G1 phase and also inhibits tumor angiogenesis by reducing synthesis of VEGF.
A Phase II trial of Evorolimus on relapsed DLBCL patients showed a 30% Overall Response Rate (ORR).
Syk inhibitors include :
- Fostamatinib
- Tamatinib
Chronic signaling through the B-cell receptor appears to contribute to the survival of DLBCL. These survival signals can be blocked by Syk inhibitors. However, since the BCR signaling pathway is not as important to the GCB DLBCL as it is to the ABC subtype, Syk inhibitors may not be effective against GCB DLBCL
Generally, acute myeloid leukemia is treated using chemotherapy consisting of an induction phase and consolidation phase (Dohner et al., 2009). Patients may also consider hematopoietic stem cell transplantation as a second mode of tackling the cancer. The most novel research is being done in tyrosine kinase inhibitors; however M2 acute myeloid leukemia treatment research involves molecules that inhibit the fusion oncoprotein AML1-ETO. Therefore, in terms of M2 subtype acute myeloid leukemia, the most prominent target is the abnormal AML1-ETO fusion protein. Similarly, chronic myeloid leukemia (CML) is comparable to acute myeloid leukemia M2 because it also forms a fusion oncoprotein – BCR-Abl. The developed tyrosine kinase inhibitor, imatinib mesylate, has had a tremendous effect on stopping cancer progression in the majority of chronic myeloid leukemia patients. BCR-Abl is constitutively active due chromosome translocation; therefore it over-phosphorylates the tyrosine kinase. Imatinib mesylate works to block BCR-Abl’s activity by blocking the active kinase domain (Fava et al., 2011).
Celastrol is a compound extracted from Tripterygium wilfordii that has anti-cancer properties. It was found to inhibit cell proliferation through the down regulation of AML1-ETO fusion oncoprotein. Celastrol inhibits the fusion oncoprotein by inducing mitochondrial instability and initiating caspase activity The decrease of AML1-ETO also results in lower levels of C-KIT kinases, Akt/PKB, STAT3, and Erk1/2 – all of which are involved in cell signaling and gene transcription (Yu et al., 2016).
Histone deacetylase inhibitors such as valproic acid (VPA), vorinostat, and all-trans retinoic acid (ATRA) are effective in targeting acute myeloid leukemia with the AML1-ETO fusion protein. The HDAC inhibitors are known to induce apoptosis through accumulation of DNA damage, inhibition of DNA repair, and activation of caspases. These inhibitors are extra sensitive to the fusion proteins. Vorinostat has been proven to cause a greater accumulation of DNA damage in fusion protein expressing cells and is directly correlated with the reduction of DNA repair enzymes (Garcia et al., 2008). Romidepsin, a drug in phase two clinical trials, has demonstrated higher efficacy in patients with AML1-ETO fusion protein leukemia (Odenike et al., 2008). Although many clinical evaluations have proven HDAC inhibitors have a promising effect on M2 subtype acute myeloid leukemia, it has not been approved as an official treatment.
In t(6;9) acute myeloid leukemia, FLT3-ITD and the DEK-NUP214 protein are potential targets for treatment. Sorafenib is a kinase inhibitor used as a treatment for kidney and liver cancer. The kinase inhibitor blocks serine-threonine kinase RAF-1 as well as FLT-ITD (Kindler, 2010). The drug has been proven to be effective in reducing FLT3-ITD overexpression (Metzelder et al., 2009). In patients with DEK-NUP214, it was found that the fusion oncoprotein caused an upregulation of mTORC1 (Sanden et al., 2013). Thus, a mTORC inhibitor could be a potential treatment.
Combined modality therapy is the most common approach for the initial treatment of thyroid lymphomas. The CHOP regimen (cyclophosphamide, doxorubicin, vincristine and prednisone) has been shown high effectiveness for many types of thyroid lymphoma. However, it is suggested to perform radiation therapy only for MALT resulting a 96% complete response, with only a 30% relapse rate. Surgical treatment might be performed for patients with thyroid lymphoma in addition to chemotherapy and radiation, particularly for MALT lymphomas.
Treatment with dose-adjusted EPOCH with rituximab has shown promising initial results in a small series of patients (n=17), with a 100% response rate, and 100% overall survival and progression-free survival at 28 months (median follow-up).
Treatment for X-linked SCID can be divided into two main groups, the prophylactic treatment (i.e. preventative) and curative treatment. The former attempts to manage the opportunistic infections common to SCID patients and the latter aims at reconstituting healthy T-lymphocyte function.
From the late 60s to early 70s, physicians began using "bubbles", which were plastic enclosures used to house newborns suspected to have SCIDS, immediately after birth. The bubble, a form of isolation, was a sterile environment which meant the infant would avoid infections caused by common and lethal pathogens. On the other hand, prophylactic treatments used today for X-linked SCID are similar to those used to treat other primary immunodeficiencies. There are three types of prophylactic treatments, namely, the use of medication, sterile environments, and intravenous immunoglobulin therapy (IVIG). First, antibiotics or antivirals are administered to control opportunistic infections, such as fluconazole for candidiasis, and acyclovir to prevent herpes virus infection. In addition, the patient can also undergo intravenous immunoglobulin (IVIG) supplementation. Here, a catheter is inserted into the vein and a fluid, containing antibodies normally made by B-cells, is injected into the patient's body. Antibodies, Y-shaped proteins created by plasma cells, recognize and neutralize any pathogens in the body. However, the IVIG is expensive, in terms of time and finance. Therefore, the aforementioned treatments only prevent the infections, and are by no means a cure for X-linked SCID.
Bone marrow transplantation (BMT) is a standard curative procedure and results in a full immune reconstitution, if the treatment is successful. Firstly, a bone marrow transplant requires a human leukocyte antigen (HLA) match between the donor and the recipient. The HLA is distinct from person to person, which means the immune system utilizes the HLA to distinguish self from foreign cells. Furthermore, a BMT can be allogenic or autologous, which means the donor and recipient of bone marrow can be two different people or the same person, respectively. The autologous BMT involves a full HLA match, whereas, the allogenic BMT involves a full or half (haploidentical) HLA match. Particularly, in the allogenic BMT the chances of graft-versus-host-disease occurring is high if the match of the donor and recipient is not close enough. In this case, the T-cells in the donor bone marrow attack the patient's body because the body is foreign to this graft. The depletion of T-cells in the donor tissue and a close HLA match will reduce the chances of graft-versus-host disease occurring. Moreover, patients who received an exact HLA match had normal functioning T-cells in fourteen days. However, those who received a haploidentical HLA match, their T-cells started to function after four months. In addition, the reason BMT is a permanent solution is because the bone marrow contains multipotent hematopoietic stem cells which become common lymphoid or common myeloid progenitors. In particular, the common lymphoid progenitor gives rise to the lymphocytes involved in the immune response (B-cell, T-cell, natural killer cell). Therefore, a BMT will result in a full immune reconstitution but there are aspects of BMT that need to be improved (i.e. GvHD).
Gene therapy is another treatment option which is available only for clinical trials. X-linked SCID is a monogenic disorder, the IL2RG gene is mutated, so gene therapy will replace this mutated gene with a normal one. This will result in a normal functioning gamma chain protein of the interleukin receptor. In order to transfer a functional gene into the target cell, viral or non-viral vectors can be employed. Viral vectors, such as the retrovirus, that incorporate the gene into the genome result in long-term effects. This, coupled with the bone marrow stem cells, has been successful in treating individuals with X-SCID. In one particular trial by Cavazzana-Calvo et al., ten children were treated with gene therapy at infancy for X-SCID. Nine of the ten were cured of X-SCID. However, about three years after treatment, two of the children developed T-cell leukemia due to insertion of the IL2RG gene near the LMO2 gene and thereby activating the LMO2 gene (a known oncogene). A third child developed leukemia within two years of that study being published, likely as a direct result of the therapy. This condition is known as insertional mutagenesis, where the random insertion of a gene interferes with the tumor suppressor gene or stimulates an oncogene. There is currently no approved gene therapy on the market, but there are many clinical trials into which X-SCID patients may enroll. Therefore, research in the field of gene therapy today and in the future is needed to avoid the occurrence of leukemia. In particular, research into the use of insulator and suicide genes is warranted as this may prevent cancer from developing. The insulator gene inhibits the activation of adjacent genes. On the other hand, the suicide gene is stimulated when a tumour begins to form, and this will result in the deactivation of the therapeutic gene. Moreover, the use of restriction enzymes such as the zinc-finger nuclease (ZFN) is being studied. The ZFN allows the researcher to choose the site of gene integration. Vector safety is important in the field of gene therapy, hence vectors that self-inactivate the promoter and enhancer (SIN) and adenoviruses that creates no immune response are prominent areas of research for vector biologists.
There is currently minimal therapeutic intervention available for BENTA disease. Patients are closely monitored for infections and for signs of monoclonal or oligoclonal B cell expansion that could indicate B cell malignancy. Splenectomy is unlikely to reduce B cell burden; peripheral blood B cell counts rose significantly in three patients who underwent the procedure. It remains to be determined whether immunosuppressive drugs, including B cell-depleting drugs such as rituximab, could be effective for treating BENTA disease.
Radiotherapy is the most effective treatment for local disease either as the sole treatment for low-grade lymphoma or in combination with chemotherapy for intermediate- and high-grade lymphoma. Radiotherapy dose in range of 30-45 Gy administered in fractions are advised in treating the local orbital lymphomas.
Recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) can be used as a temporary cure. GM-CSF stimulates production of white blood cells. This cure is commonly used in patients who are awaiting bone marrow transplantation. Response to this cure can vary. Those with a more severe combined immunodeficiency may have no response to this therapy.
In terms of the management of T cell deficiency for those individuals with this condition the following can be applied:
- Killed vaccines should be used(not "live vaccines" in T cell deficiency)
- Bone marrow transplant
- Immunoglobulin replacement
- Antiviral therapy
- Supplemental nutrition
The survival range is estimated to be 3 days to 17 weeks without treatment. Patients die due to bacterial or viral infections. Aggressive treatment with antibiotics is required and bone marrow transplant is common. Patients undergoing bone marrow transplant, specifically from a matched sibling, have a higher 5 year survival rate than those receiving a transplant from other donors.
In terms of treatment for hyper Igm syndrome there is the use of allogeneic hematopoietic cell transplantation. Additionally anti-microbial therapy, use of granulocyte colony-stimulating factor, immunosuppressants, as well as, other treatments may be needed.
X-linked SCID is a known pediatric emergency which primarily affects males. If the appropriate treatment such as intravenous immunoglobulin supplements, medications for treating infections or a bone marrow transplant is not administered, then the prognosis is poor. The patients with X-linked SCID usually die two years after they are born. For this reason, the diagnosis of X-linked SCID needs to be done early to prevent any pathogens from infecting the infant.
However, the patients have a higher chance of survival if the diagnosis of X-linked SCID is done as soon as the baby is born. This involves taking preventative measures to avoid any infections that can cause death. For example, David Vetter had a high chance of having X-linked SCID because his elder sibling had died due to SCID. This allowed the doctors to place David in the bubble and prevented infections. In addition, if X-linked SCID is known to affect a child, then live vaccines should not be administered and this can save the infants life. Vaccines, which are pathogens inserted into the body to create an immune response, can lead to death in infants with X-linked SCID. Moreover, with proper treatments, such as a bone marrow transplant, the prognosis is good. The bone marrow transplant has been successful in treating several patients and resulted in a full immune reconstitution and the patient can live a healthy life. The results of bone marrow transplant are most successful when the closest human leukocyte antigen match has been found. If a close match is not found, however, there is a chance of graft-versus-host-disease which means the donor bone marrow attacks the patient's body. Hence, a close match is required to prevent any complications.
The only treatment for Omenn syndrome is chemotherapy followed by a bone marrow transplantation. Without treatment, it is rapidly fatal in infancy.
The most common treatment for SCID is bone marrow transplantation, which has been successful using either a matched related or unrelated donor, or a half-matched donor, who would be either parent. The half-matched type of transplant is called haploidentical. Haploidentical bone marrow transplants require the donor marrow to be depleted of all mature T cells to avoid the occurrence of graft-versus-host disease (GVHD). Consequently, a functional immune system takes longer to develop in a patient who receives a haploidentical bone marrow transplant compared to a patient receiving a matched transplant. David Vetter, the original "bubble boy", had one of the first transplantations, but eventually died because of an unscreened virus, Epstein-Barr (tests were not available at the time), in his newly transplanted bone marrow from his sister, an unmatched bone marrow donor. Today, transplants done in the first three months of life have a high success rate. Physicians have also had some success with "in utero" transplants done before the child is born and also by using cord blood which is rich in stem cells. "In utero" transplants allow for the fetus to develop a functional immune system in the sterile environment of the uterus; however complications such as GVHD would be difficult to detect or treat if they were to occur.
More recently gene therapy has been attempted as an alternative to the bone marrow transplant. Transduction of the missing gene to hematopoietic stem cells using viral vectors is being tested in ADA SCID and X-linked SCID. In 1990, four-year-old Ashanthi DeSilva became the first patient to undergo successful gene therapy. Researchers collected samples of DeSilva's blood, isolated some of her white blood cells, and used a retrovirus to insert a healthy adenosine deaminase (ADA) gene into them. These cells were then injected back into her body, and began to express a normal enzyme. This, augmented by weekly injections of ADA, corrected her deficiency. However, the concurrent treatment of ADA injections may impair the success of gene therapy, since transduced cells will have no selective advantage to proliferate if untransduced cells can survive in the presence of the injected ADA.
In 2000, a gene therapy "success" resulted in SCID patients with a functional immune system. These trials were stopped when it was discovered that two of ten patients in one trial had developed leukemia resulting from the insertion of the gene-carrying retrovirus near an oncogene. In 2007, four of the ten patients have developed leukemias. Work aimed at improving gene therapy is now focusing on modifying the viral vector to reduce the likelihood of oncogenesis and using zinc-finger nucleases to more specifically target gene insertion. No leukemia cases have yet been seen in trials of ADA-SCID, which does not involve the "gamma c" gene that may be oncogenic when expressed by a retrovirus.
Trial treatments of SCID have been gene therapy's first success; since 1999, gene therapy has restored the immune systems of at least 17 children with two forms (ADA-SCID and X-SCID) of the disorder.
There are also some non-curative methods for treating SCID. Reverse isolation involves the use of laminar air flow and mechanical barriers (to avoid physical contact with others) to isolate the patient from any harmful pathogens present in the external environment. A non-curative treatment for patients with ADA-SCID is enzyme replacement therapy, in which the patient is injected with polyethyleneglycol-coupled adenosine deaminase (PEG-ADA) which metabolizes the toxic substrates of the ADA enzyme and prevents their accumulation. Treatment with PEG-ADA may be used to restore T cell function in the short term, enough to clear any existing infections before proceeding with curative treatment such as a bone marrow transplant.
Autophagy is an innate pathway used for degradation of cellular components (Kobayashi, 2015). In recent studies, scientists recognize the significance of autophagy both as a potential anti-apoptotic response to cancer treatments as well as a potential mechanism for getting rid of undesirable fusion proteins such as AML1-ETO. In a 2013 study, scientists demonstrated that the degradation of fusion oncoprotein AML1-ETO is not mediated by autophagy through a set of drug dosage trials testing the levels of AML1-ETO protein expression. The acute myeloid leukemia Kasumi-1 cell line was selected for the experiment due to its AML1-ETO positive characteristics. These cells were treated with increasing concentrations of each histone deacetylase inhibitors – valproic acid (VPA) (epileptic and bipolar drug) or vorinostat (cutaneous T cell lymphoma drug), which are known to induce autophagy associated with loss of the fusion protein. The two inhibitors were added to the cell line in doses of 0, 0.38 uM, 0.74 uM, and 1.5 uM. The cell lysates were then treated with autophagy inhibitors Baf or CQ, or control. Through immunoblotting, there is no reduction of AML1-ETO observed across the different concentrations of VPA or vorinostat. The results indicate that AML1-ETO degradation is not mediated by autophagy, but there is an observed pro-survival autophagy in the leukemic cells (Torgersen et al., 2013). Thus, an inhibition of autophagy would be a viable treatment method for subtype M2 acute myeloid leukemia.