Acute Effects of Various Chemotherapeutic Combinations on Hypophyseal and Pineal Hormone Secretions in Cancer Patients

Involvement of the Opioid Peptide Family in Cancer Progression

Peptides mediate cancer progression favoring the mitogenesis, migration, and invasion of tumor cells, promoting metastasis and anti-apoptotic mechanisms, and facilitating angiogenesis/lymphangiogenesis. Tumor cells overexpress peptide receptors, crucial targets for developing specific treatments against cancer cells using peptide receptor antagonists and promoting apoptosis in tumor cells. Opioids exert an antitumoral effect, whereas others promote tumor growth and metastasis. This review updates the findings regarding the involvement of opioid peptides (enkephalins, endorphins, and dynorphins) in cancer development. Anticancer therapeutic strategies targeting the opioid peptidergic system and the main research lines to be developed regarding the topic reviewed are suggested. There is much to investigate about opioid peptides and cancer: basic information is scarce, incomplete, or absent in many tumors. This knowledge is crucial since promising anticancer strategies could be developed alone or in combination therapies with chemotherapy/radiotherapy.

Testicular dose and hormonal changes after radiotherapy of rectal cancer

BACKGROUND AND PURPOSE

To measure the dose received by the testicles during radiotherapy for rectal cancer and to determine the contribution of each field of the pelvic box and the relevance for hormonal status.

MATERIALS AND METHODS

In 11 patients (mean age 55.2 years) testicular doses were measured with an ionisation chamber between 7 and 10 times during the course of pelvic radiotherapy (50 Gy) for rectal carcinoma. Before and several months after radiotherapy luteinizing hormone, follicle stimulating hormone and total testosterone serum levels were determined.

RESULTS

The mean cumulative radiation exposure to the testicles was 3.56 Gy (0.7-8.4 Gy; 7.1% of the prescribed dose). Seventy-three percent received more than 2 Gy to the testicles. Fifty-eight percent of the measured dose was contributed by the p.a. field, 30% by the a.p. field and 12% by the lateral fields. Mean LH and FSH levels were significantly increased after therapy (350%/185% of the pre-treatment values), testosterone levels decreased to 78%. No correlation could be found between changes of hormones and doses to the testis, probably due to the low number of evaluated patients.

CONCLUSIONS

Radiotherapy of rectal carcinoma causes significant damage to the testis, as shown by increased levels of gonadotropins after radiotherapy. Most of the gonadal dose is delivered by the p.a. field, due to the divergence of the p.a. beam towards the testicles. The reduction in testosterone level may be of clinical concern. Patients who will receive radiotherapy for rectal carcinoma must be instructed about a high risk of permanent infertility, and the risk of endocrine failure (hypogonadism). Larger studies are needed to establish the correlation between testicular radiation dose and hormonal changes in this group of patients.

Influence of adjuvant chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil on plasma melatonin and chosen hormones in breast cancer premenopausal patients

OBJECTIVE

To investigate the effect of chemotherapy on levels of melatonin in patients with breast cancer.

BACKGROUND

In light of reports on the possible oncostatic role of melatonin in breast cancer patients, it is essential to know the influence of adjuvant chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF) on plasma melatonin concentration as well as on its contributing factors, e.g. current hormonal state of the organism. The combination therapy is one of the oldest, safest and most commonly prescribed adjuvant treatments.

METHOD

Twenty-four breast cancer patients on CMF chemotherapy were studied along with a control group of 16 healthy pre-menopausal women.

RESULTS

Plasma melatonin concentration (determined by RIA method) in breast cancer patients prior to treatment did not differ significantly from that of healthy women, but it was significantly increased after the initial cycle of CMF, and significantly increased as compared to a group of healthy women. We did not notice any significant interactions between plasma melatonin and growth hormone, prolactin, estradiol, progesterone, cortisol and met-enkephalin concentrations in all studied groups.

CONCLUSION

The possible oncostatic action of melatonin warrants further investigation to elucidate whether the induced increase of blood melatonin concentration is essential to successful CMF chemotherapy.

Alterations in laboratory test results during adjuvant breast cancer treatment

An increasing number of women is treated with adjuvant cyclophosphamide, methotrexate and 5-fluorouracil therapy for breast cancer. The effects of the chemotherapy on many laboratory tests are, however, inadequately known. This study investigates the effects of the treatment on various laboratory tests. Fifteen premenopausal women receiving adjuvant cyclophosphamide, methotrexate and 5-fluorouracil chemotherapy and optional radiotherapy were included in the study. Common hormonal, biochemical, hematological, protein and lipid laboratory tests were taken serially during a 10-month follow-up. Twelve women became amenorrheic. Their serum follicle stimulating hormone and luteinising hormone concentrations increased accordingly. Other serum hormones (testosterone, androstenedione, sex hormone-binding globulin, prolactin, dehydroepiandrosterone sulfate, cortisol, parathyroid hormone and thyroid hormones) changed only slightly. Hemoglobin concentration and white blood cell count decreased slightly. Serum alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine kinase, angiotensin-converting enzyme, amylase, glucose, potassium, phosphate, urea and triglycerides concentrations increased slightly whereas serum bilirubin, haptoglobin, and immunoglobulin A and M decreased slightly. Serum alpha1-antitrypsin fluctuated around the baseline concentration. Other test results remained at their pretreatment concentrations. With the exception of increases in serum gonadotrophins, the changes observed were slight and the mean concentrations remained within reference limits. Therefore, cyclophosphamide, methotrexate and 5-fluorouracil adjuvant treatment is unlikely to complicate the diagnosis of other diseases.

Is positive correlation between cortisol and met-enkephalin concentration in blood of women with breast cancer a reaction to stress before chemotherapy administration?

The role of stress in the course of neoplastic diseases has been emphasised over the past few years. Organism defence in form of increased release of hormones, corticosteroids and endogenous opioids should be assessed as a particular form of adaptation. Interactions between stress hormones and others which may influence the growth of breast cancer cells are possible. In this study, the concentration of cortisol and met-enkephalin vis-à-vis growth hormone, insulin-like growth factor-I, prolactin, estradiol, progesterone and melatonin in blood of women with breast cancer before the first cycle of supplementary chemotherapy was compared to that of healthy women. In a group of patients with breast cancer, before the first cycle of chemotherapy, high hypercortisolemia and positive correlation between cortisol and met-enkephalin was observed which may be a result of stress at the beginning of such treatment. A negative correlation between prolactin and met-enkephalin in this group can indirectly testify to essential participation of endogenous opioids in hormonal regulation and can be a response to stress caused by beginning chemotherapy.