Does cyclosporin A cause cancer?

Differential dose-response effect of cyclosporine A in regulating apoptosis and autophagy markers in MCF-7 cells

Cyclosporine A (CsA) is an immunosuppressant primarily used at a higher dosage in transplant medicine and autoimmune diseases with a higher success rate. At lower doses, CsA exhibits immunomodulatory properties. CsA has also been reported to inhibit breast cancer cell growth by downregulating the expression of pyruvate kinase. However, differential dose-response effects of CsA in cell growth, colonization, apoptosis, and autophagy remain largely unidentified in breast cancer cells. Herein, we showed the cell growth-inhibiting effects of CsA by preventing cell colonization and enhancing DNA damage and apoptotic index at a relatively lower concentration of 2 µM in MCF-7 breast cancer cells. However, at a higher concentration of 20 µM, CsA leads to differential expression of autophagy-related genes ATG1, ATG8, and ATG9 and apoptosis-associated markers, such as Bcl-2, Bcl-XL, Bad, and Bax, indicating a dose-response effect on differential cell death mechanisms in MCF-7 cells. This was confirmed in the protein-protein interaction network of COX-2 (PTGS2), a prime target of CsA, which had close interactions with Bcl-2, p53, EGFR, and STAT3. Furthermore, we investigated the combined effect of CsA with SHP2/PI3K-AKT inhibitors showing significant MCF-7 cell growth reduction, suggesting its potential to use as an adjuvant during breast cancer therapy.

Increased incidence of colorectal malignancies in renal transplant recipients: a case control study

This study was to evaluate the frequency of colorectal neoplasia in renal transplant recipients and to investigate the association with Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infection. We compared the frequency of colorectal neoplasia among renal transplant recipients with that of the healthy subjects. Specimens of colorectal neoplasia were examined for EBV and CMV using in situ hybridization and immunohistochemistry, respectively. Of 796 renal transplantation cohorts, 315 were enrolled. The frequency of colorectal neoplasia among the patients was 22.9%. Compared with the healthy subjects, the odds ratio (OR) for advanced adenoma was 3.32 (95% CI, 1.81-6.10). The frequency of cancer among the patients was 1.9% (OR, 12.0; 95% CI, 1.45-99.7). A long interval between transplantation and colonoscopy was a significant factor in the development of advanced colorectal neoplasia. EBV positivity was detected in 30.6% of colorectal neoplasia specimens from renal transplant recipients, which was higher than that for the controls (p = 0.002). CMV was not detected in any lesions of patients or controls. In conclusion, renal transplant recipients have a significantly increased risk of advanced colorectal neoplasia. EBV was more frequently found in specimens of advanced colorectal neoplasm obtained from the renal transplant recipients.

Risk factors for malignancy in Japanese renal transplant recipients

BACKGROUND

Among recipients of renal transplants, the incidences of renal cancer and gastrointestinal cancer are higher and that of skin cancer is much lower in Japan than in Europe and North America.

METHODS

The risk factors for the development of malignant tumors were examined in Japanese recipients of renal transplants. A total of 556 patients underwent renal transplantation at the Department of Urology, Osaka University Faculty of Medicine between March 1, 1965, and April 31, 2004. Of these patients, 366 were retrospectively studied in whom risk factors potentially related to the development of malignancy could be evaluated on the basis of medical records. The incidence of malignancy, survival rate, and risk factors for malignancy were examined.

RESULTS

The overall incidence of malignancy was 6.8% (25/366 patients). Six of the 25 patients with malignancy died of cancer, but there was no correlation between the occurrence of malignancy and the survival rate (P = .8058, log-rank test). A Cox proportional-hazards model identified treatment with tacrolimus (hazard ratio [HR] = 4.376; 95% confidence interval [CI]: 1.647-11.627; P = .0031) and age at transplantation (HR = 1.562; 95% CI: 1.089-2.240; P = .0155) as risk factors for malignancy.

CONCLUSIONS

The results of multivariate analysis suggested that age at transplantation and the use of tacrolimus were independent risk factors for the development of malignancy in recipients of renal transplants.

Chronic myelogenous leukemia that occurred two years after the diagnosis of adult Still's disease

A 25-year-old Japanese man was diagnosed with steroid-resistant Adult Still's Disease (ASD) in August 2000. No evidence of chronic myelogenous leukemia (CML) had been found during admissions in 2000 and 2001. In August 2002, he was diagnosed with CML with a peripheral white blood count of 69,940/microl and positivity for Philadelphia chromosome and BCR/ABL fusion gene on bone marrow aspiration. No case of CML was reported to develop from ASD. Because a diagnosis of ASD is based on the exclusion of other diseases, we must be cognizant of the possibility of the development of concurrent diseases.

Malignancies in organ transplant recipients

The development of cancer in organ transplant recipients is well known; depressed immunosurveillance induced by the use of immunosuppressive agents for prevention of rejection is a causative factor. The types of malignancies in renal transplant patients vary geographically and are influenced by the type of immunosuppressant used. In the present study in Japan, malignancies had developed in 2.6% of renal transplant recipients; the observed number/expected number ratio was 2.78. For the primary sites, the relative risk in Japan was quite different from that in Western countries, with a lower frequency of skin cancer, an absence of Kaposi's sarcoma and higher frequencies of renal and thyroid cancer in Japan. Epstein-Barr virus is an oncogenic virus causing lymphoproliferative disorders in immunocompromised hosts. In renal transplant recipients, who usually receive hemodialysis before transplantation, human T lymphotrophic virus (HTLV)-1 is also oncogenic and causes adult T-cell leukemia/lymphoma. The HTLV-1 in donor blood might be transmitted to transplant recipients via transfusion during hemodialysis. The epidemiology and characteristics of representative malignancies in transplant recipients are described, with a review of pertinent literature.

Is posttransplant lymphoproliferative disorder (PTLD) caused by any specific immunosuppressive drug or by the transplantation per se?

BACKGROUND

An association between posttransplant lymphoproliferative disorder (PTLD) and cyclosporine A (CsA) and OKT3 has often been postulated on the basis of retrospective studies, although a randomized study with PTLD as the endpoint will probably never be performed. Because focus on PTLD coincided with the use of these drugs, a bias could be suspected.

METHODS

In a retrospective, nonrandomized study, we reevaluated all lymphoma-like lesions arising in kidney-transplant patients grafted at our center during 1969 to 1998 and observed up to 2002. Case pathology was reviewed, and an association with Epstein-Barr virus (EBV) infection (and latency pattern) was assessed.

RESULTS

We did not find any significant difference in the incidence of PTLDs when comparing the prednisolone/azathioprine, and CsA eras (P=0.89), the periods before or after OKT3 (P=0.61), and those before or after antilymphocyte globulin (ALG) (P=0.22). Occurrence time was shorter in the CsA (P=0.059), OKT3 (P=0.007), and ALG (P=0.007) eras. In the OKT3 era, 182 patients received, and 224 did not receive, OKT3; after the same observation time, there had been eight and five PTLDs, respectively (P=0.34). The use of mycophenolate mofetil (MMF) was associated with a reduction in the number of PTLDs (P=0.01). EBV was detected in 16 of 21 (76%) cases.

CONCLUSIONS

We found no evidence to implicate any one drug regime preferentially in the development of PTLDs. The risk of developing PTLD seems to be a result of the whole transplantation process, which includes the antigenicity of the foreign graft, the immunosuppression resulting in inadequate cytotoxic T-cell activity, and the result of EBV infection. An important minority of cases are EBV negative.

Management of squamous cell carcinoma in organ transplant recipients

The number of skin cancers continues to rise with well over one million cases of skin cancer expected in the United States this year. Optimal management depends on early detection and treatment. The consequences of skin cancer may be particularly devastating in organ transplant recipients. In this article, management of squamous cell carcinoma in the organ transplant recipient is discussed.