Changes in serum erythropoietin levels during chemotherapy for lung cancer

A genetic variation associated with plasma erythropoietin and a non-coding transcript of PRKAR1A in sickle cell disease

Blood erythropoietin (EPO) increases primarily to hypoxia. In sickle cell anaemia (homozygous HBBE6V; HbSS), plasma EPO is elevated due to hemolytic anaemia-related hypoxia. Hydroxyurea treatment reduces haemolysis and anaemia by increasing foetal haemoglobin, which leads to lower hypoxic transcriptional responses in blood mononuclear cells but paradoxically further increases EPO. To investigate this apparent hypoxia-independent EPO regulation, we assessed two sickle cell disease (SCD) cohorts for genetic associations with plasma EPO, by prioritizing 237,079 quantitative trait loci for expression level and/or transcript isoform variations of 12,727 genes derived from SCD blood mononuclear cells. We found an association between the T allele of SNP rs60684937 and increased plasma EPO (n = 567, combined P = 5.5 × 10 − 8 adjusted for haemoglobin and hydroxyurea) and validated it in independent SCD patients (n = 183, P = 0.018). The T allele of rs60684937 was associated with a relatively increased expression of a non-coding transcript of PRKAR1A (cAMP-dependent protein kinase type I-alpha regulatory subunit) in 58 SCD patients (P = 7.9 × 10 − 7) and 58 HapMap Yoruba samples (P = 0.0011). In conclusion, we demonstrate that plasma EPO elevation with hydroxyurea in SCD is independent of hypoxic responses and that genetic variation at SNP rs60684937 may contribute to EPO regulation through a cAMP-dependent protein kinase A pathway.

Baseline and early treatment factors are not clinically useful for predicting individual response to erythropoietin in anemic cancer patients

Recombinant human erythropoietin (rHuEPO) is an effective treatment for anemia in patients with cancer, and recent studies show that over two-thirds of patients can be expected to respond with a large increase (>2 g/dl) in hemoglobin concentration. However, it would be helpful to identify likely responders and nonresponders before initiating treatment. Previous studies have suggested that high pretreatment endogenous erythropoietin levels are associated with a lower response to erythropoietin, especially in certain patient groups, such as patients with hematological malignancies, non-chemotherapy patients, or patients with myelodysplastic syndrome. Various algorithms have therefore been developed to predict patient response to rHuEPO using baseline serum erythropoietin levels and other baseline factors. We performed an analysis of data pooled from four randomized clinical trials of 604 patients with non-myeloid malignancies, examining the clinical usefulness of pretreatment and early treatment factors for predicting response to erythropoietin. The analysis confirms several other reports that the most predictive models combined pretreatment and early treatment factors, including change in hemoglobin at 4 weeks, but even these models did not increase sensitivity above 85% (total response in unselected patients was 68.1%), while specificity remained poor. We conclude that clinically useful prediction of response to erythropoietin is not possible using baseline or early response variables because of poor sensitivity and specificity of prediction compared with generally accepted clinical tests.

Serum erythropoietin levels in ovarian cancer patients receiving chemotherapy

OBJECTIVE

To investigate the effects of repeated cis-dichlorodiamine-platinum (CDDP) exposure on serum erythropoietin (Epo) levels.

STUDY DESIGN

In seven patients with ovarian cancer, Epo and haemoglobin concentration (c(Hb)) were measured before, 24h and 7 days after administration of the first three courses of chemotherapy. In seven control patients undergoing gynaecological surgery for non-malignant reasons, Epo and c(Hb) were measured before, 24h and 7 days after the operation.

RESULTS

Following Epo increased, independent of concomitant anaemia, especially after the third course: 51mU/ml (S.D. 46) versus 122mU/ml (S.D. 83) (P=0.02). In the control patients, Epo was lower although the decrease of c(Hb) was significantly higher.

CONCLUSION

Cis-platinum chemotherapy induces an increase in erythropoietin levels independent of anaemia. The underlying mechanism remains to be investigated.

Serum erythropoietin level in anemic cancer patients

Anemia is a frequent complication of cancer and its treatment. A defect in erythropoietin production has been advocated as being the main cause of anemia in cancer patients. We studied serum erythropoietin levels in 74 patients with solid tumors and in a control group consisting of 20 otherwise healthy individuals without any malignancy, who have only iron deficiency anemia. Serum erythropoietin levels were measured by enzyme immunoassay in cancer patients without anemia (n=34), and in anemic cancer patients (n=40); either receiving chemotherapy (n=21) or not (n=19). Anemic cancer patients were found to have decreased response of erythropoietin for a given hemoglobin level (mean, 40.1+/-34.7 u/ml), compared with the patients having only iron deficiency anemia (mean, 69.7+/-68.6 u/ml) (P<0.05). In patients with iron deficiency anemia having no malignancy, erythropoietin response was remarkably high and inversely correlated with the level of hemoglobin (r=-0.69; P=0. 05). Although there was no correlation between hemoglobin and erythropoietin response in cancer anemia (r=-0.07), serum levels of erythropoietin were found to be higher in anemic cancer patients (mean, 40.1+/-34.7 u/ml), compared with cancer patients with normal hemoglobin values (mean, 19.96+/-18.4 u/ml). There was not any statistically significant difference between erythropoietin levels in anemic cancer patients with or without chemotherapy (mean, 43. 7+/-37.7 u/ml and 41.9+/-30.08 u/ml respectively; P>0.05). No difference in serum erythropoietin levels were noted in patients treated with cisplatin or non-cisplatin containing regimens (mean, 48.36+/-33.12 u/ml and 38.55+/-43.52 u/ml, respectively; P>0.05). In this study, we demonstrated that anemia in cancer patients was caused by blunted erythropoietin response, rather than its quantitative deficiency. Serial measurements, however, should be considered in patients receiving chemotherapy.

Changes in levels of serum erythropoietin, serum iron and unsaturated iron binding capacity during chemotherapy for lung cancer

BACKGROUND

The serum erythropoietin level increases markedly during chemotherapy for leukemia. A number of hypotheses have been built for the mechanism, none of them satisfactory. Difficulty in evaluating bone marrow activity hampers the elucidation. Therefore, we focused on patients who had non-hematological cancer and no evidence of bone marrow suppression.

METHODS

Twelve patients, who had lung cancer (four with small cell cancer and eight with non-small cell cancer) and who had not undergone any chemotherapy, were studied. During chemotherapy, we measured serum erythropoietin, serum iron, unsaturated iron binding capacity and hemoglobin concentration in these patients.

RESULTS

The serum erythropoietin level before chemotherapy (10.8 +/- 7.4 mU/ml) was within the normal range but the peak values after the first treatment (73.4 +/- 90.4 mU/ml) increased in all patients. In the patients with small cell cancer, a transient but marked increase in erythropoietin value (204.6 +/- 167.3 mU/ml) was observed after each session of chemotherapy while hemoglobin concentration decreased gradually. Throughout treatments, elevation of the serum iron concentration and concomitant reduction of unsaturated iron binding capacity were observed after each session of chemotherapy. They regained their original values whilst the serum erythropoietin level decreased after each chemotherapy session was completed.

CONCLUSIONS

It is suggested that the suppression of erythroid marrow by chemotherapeutic agents causes the changes in serum erythropoietin level during chemotherapy in patients with lung cancer.