Plasma prolactin in patients with colorectal cancer

Correlation of Plasma Prolactin and Carcinoembryonic Antigen in Colorectal Cancer

Background Carcinoembryonic antigen (CEA) has been widely used as a prognostic marker in colorectal cancer for decades. Elevated levels of prolactin have also been observed in various cancers, including CRC; however, the role of elevated prolactin in colorectal cancer remains unclear. Objective This study aimed to investigate the correlation between plasma prolactin and CEA levels in patients with colorectal cancer. Materials and methods In this observational study, 80 colorectal cancer patients were included. Serum levels of prolactin and CEA were measured using chemiluminescence assay (Siemens AdviaCentaur XP, Siemens Healthineers, Erlangen, Germany). Statistical analysis was performed using the chi-square test, unpaired t-test, and analysis of variance (ANOVA) to evaluate correlations between the two biomarkers. Results Our results showed elevated levels of both plasma prolactin and CEA in colorectal cancer patients. A positive correlation was found between serum prolactin and CEA levels in the patient population. Conclusion The present study found elevated serum prolactin levels in most patients with raised CEA levels. Further research is required to better understand the role of prolactin as a potential prognostic factor in colorectal cancer and to establish the relationship between serum prolactin and CEA.

The Value of Prolactin, a Panel of Cytokines, and the Soluble Human Epidermal Growth Factor Receptor 2 in the Prediction of Rapid Progression and Shorter Survival during Palliative Chemotherapy of Colorectal Cancer Patients

The prediction of colorectal cancer (CRC) response to palliative chemotherapy (CTH) is still difficult. Patients at a higher risk of progression may benefit from more aggressive treatment. This study assessed the predictive value of prolactin (PRL) and a panel of cytokines, chemokines, and growth factors for the risk of rapid progression in CRC patients starting palliative CTH. This study included 51 CRC patients initiating palliative CTH with up to 5-year follow-up, divided into rapid and non-rapid progressors. Serum samples were collected before CTH for assessment of a large panel of cytokines, chemokines, growth factors, and PRL via a multiplex method. Rapid progressors (N = 19) were characterized by increased baseline values of IL-8 and IP10 but decreased PRL levels. In addition, PRL below 18.2 ng/mL was a strong predictor of weight loss during CTH. Grade 3 (HR = 2.97; 95%CI: 1.48-5.98) and PRL level (HR = 0.96; 95%CI: 0.91-1.01) were independent risk factors of progression. We showed that CRC rapid progressors are characterized by decreased baseline PRL levels. In addition, increased baseline levels of IP-10, sHER-2, IL-6, and IL-8 may be associated with longer survival; however, larger studies are needed to confirm their predictive role in CRC patients.

A high-throughput customized cytokinome screen of colon cancer cell responses to small-molecule oncology drugs

Inflammatory cytokines, chemokines, and growth factors are molecular messengers that circulate and have the capability to modify the tumor microenvironment and impact therapeutic response. The characterization of soluble mediators as biomarkers for diagnosis and prognosis is of interest in oncology. We utilize the cytokinome to characterize the response of colorectal tumor cell lines to selected small-molecules in oncology as a proof-of-concept dataset with immunomodulatory analyte heat map rankings for drug and cell line combinations. We observed overall trends in drug class effects with MEK-, BRAF-, PARP-inhibitors, and Imipridones in cytokine, chemokine, and growth factor responses that may help guide therapy selection. MEK-inhibitor treatment downregulated analytes VEGF, CXCL9/MIG, and IL-8/CXCL8 and upregulated CXCL14/BRAK, Prolactin, and CCL5/RANTES. BRAF-inhibitor treatment downregulated VEGF and IL-8/CXCL8, while increasing soluble TRAIL-R2. Treatment with PARP-inhibitors decreased CXCL9/MIG, IL-8/CXCL8, CCL3/MIP-1 alpha, VEGF, and CXCL14/BRAK, while treatment increased soluble TRAIL-R2 and prolactin. Treatment with Imipridones decreased CCL3/MIP-1 alpha, VEGF, CXCL14/BRAK, IL-8/CXCL8, and Prolactin and increased CXCL5/ENA-78. We also observed differential responses to therapeutics depending on the mutational profile of the cell line. In the future, a similar but larger dataset may be utilized in the clinic to aid in the prediction of patient response to immunomodulatory therapies based on tumor genotype.

A case of hyperprolactinaemia in a patient with metastatic melanoma

Ectopic prolactin production from a malignancy is infrequently reported. We report here a 60-year-old gentleman who presented with hyperprolactinaemia (9100 mIU/L) causing expressible galactorrhoea, decreased libido and fatigue thought to be due to ectopic prolactin secretion from a metastatic melanoma. Upon initiation of pembrolizumab, the patient's symptoms resolved and he became normoprolactinaemic. This corresponded with a partial response on radiological imaging. Although the core biopsy of the metastatic melanoma did not exhibit immunostaining for prolactin, we believe that only a subset of the tumour cells possesses prolactin-secreting capacity. This case illustrates the need to consider ectopic prolactin production for a solid malignant tumour as a rare cause of hyperprolactinaemia in patients with a normal pituitary MRI, in the absence of other causes.

Colorectal carcinoma screening: Established methods and emerging technology

Colorectal carcinoma screening programs have shown success in lowering both the incidence and mortality rate of colorectal carcinoma at a population level, in part because this carcinoma is relatively slow growing and has an identifiable premalignant lesion. Still, many patients do not undergo the recommended screening for colorectal carcinoma, and of those who do, a subset may be over- or under-diagnosed by the currently available testing methods. The primary purpose of this article is to review the data regarding currently available colorectal cancer screening modalities, which include fecal occult blood testing, direct colonic visualization, and noninvasive imaging techniques. In addition, readers will be introduced to a variety of biomarkers that may serve as stand-alone or adjunct tests in the future. Finally, there is a brief discussion of the current epidemiologic considerations that public health officials must address as they create population screening guidelines. The data we provide as laboratory physicians and scientists are critical to the construction of appropriate recommendations that ultimately decrease the burden of disease from colorectal carcinoma.

Galactorrhea, mastodynia and gynecomastia as the first manifestation of lung adenocarcinoma. A case report

Gynecomastia with mastodynia and galactorrhea as a paraneoplastic syndrome due to lung cancer with complete response after surgical excision is rare. A 62-year-old Caucasian male presented with mastodynia, galactorrhea and right breast enlargement. Chest x-ray revealed a left upper lobe tumor. The patient had high levels of serum beta-human chorionic gonadotropin (b-HCG) and prolactine. Complete staging was negative for metastases. A typical left upper lobectomy with radical mediastinal lymph node dissection was performed. Pathology report was consistent with a poorly differentiated adenocarcinoma (T₂N₁M₀). Immunohistochemically, multinucleate cells and occasional mononucleate tumor cells showed positivity for human chorionic gonadotropin. The patient received adjuvant chemotherapy with cisplatin - navelbine. One year later physical examination showed regression of both gynecomastia and mastodynia and there was no nipple discharge, while he is free from local or distant metastatic disease and the b-HCG level is normal (1,59 mIU/ml). This case represents a very rare, first manifestation of lung cancer. Galactorrhea, mastodynia and gynecomastia were the initial symptoms, which totally resolved following the successful surgical resection and adjuvant chemotherapy. In this case, prolactin and b-HCG are useful biomarkers during follow up for checking local or distal recurrence of the disease.

The mechanisms linking obesity to colon cancer: An overview

Obesity, characterised as a chronic low-grade inflammation is a crucial risk factor for colon cancer. The expansion of the adipose tissue is related to elevated triglyceride and low-density lipoprotein (LDL) levels and hyperinsulinemia, which all are presumed mediators of the tumour development. Obesity is also believed to support carcinogenesis by activating the insulin/IGF-1 pathway. Moreover, obesity increases the level of proinflammatory cytokines (e.g. TNF-α, IL-1, and IL-6) and has a significant impact on selected adipokines. This paper briefly outlines the latest evidence of the linkage between the obesity and colon cancer and discusses its possible implication for the improvement of anticancer prevention and treatment strategies connected with nutrition.

Differentiated thyroid cancer in patients with prolactinoma

BACKGROUND/AIM

Increasing evidence is available about the role of prolactin in the development of various cancers. The purpose of this study is to evaluate the frequency of thyroid cancer in patients with prolactinoma followed at a single site.

MATERIALS AND METHODS

The medical records of 182 patients diagnosed with prolactinoma were reviewed retrospectively. Serum prolactin, antithyroglobulin, antithyroid peroxidase antibody, thyroid-stimulating hormone, free T4, and free T3 values and pituitary gland magnetic resonance imaging and thyroid ultrasound reports were evaluated.

RESULTS

Forty-five (39.5%) patients were found to have a thyroid nodule (13 solitary, 32 multiple). Ten patients were administered a thyroidectomy, and differentiated thyroid cancer (DTC) was detected in 6 of these patients (6/114, 5.3%). One patient had lung metastasis. The control group consisted of 113 individuals (101 females, 12 males with a mean age of 32.1 ± 9.1). In the ultrasound reports, 28 of these individuals (24.8%) had a thyroid nodule (5 solitary, 23 multiple), and one individual (1/113, 0.8%) had DTC.

CONCLUSION

When compared to the control group, thyroid volume and thyroid nodularity were significantly higher in patients with prolactinoma (P < 0.001, P = 0.018, respectively); however, no statistically significant difference existed for the incidence of thyroid cancer (P = 0.196).

Comparative study of tumor markers in patients with colorectal carcinoma before and after chemotherapy

BACKGROUND

Colorectal carcinoma (CRC), the second leading cause of cancer-related deaths in US, has a rising time-trend in India. Tumour markers in CRC are extensively researched, and there's still debate on their diagnostic and prognostic values.

METHODS

In this hospital-based longitudinal study in north India, 51 male diagnosed CRC cases (pre-chemotherapy) were contrasted against 50 age and sex matched controls. Nine biomarkers: carcinoembryonic antigen (CEA), prolactin (PRL), alfa feto protein (AFP), total human chorionic gonadotropin (hCG), cancer antigen-125 (CA-125), serum testosterone, prostate specific antigen (PSA) and ferritin were measured by direct chemiluminescence technique. Further, follow-up was done on 47 cases after treatment with six cycles of 5-flurouracil (5-FU) and oxaliplatin.

RESULTS

Mean serum CEA (case: 5.94±8.27 ng/mL, control: 2.5±0.79 ng/mL, P<0.05), PRL (case: 28.12±13.39 ng/mL, control: 14.24±13.13 ng/mL, P<0.0001), AFP (case: 10.9±6.65 ng/mL, control: 4.02±1.26 ng/mL, P<0.0001) levels were significantly raised in CRC cases compared to controls. On the contrary, mean testosterone level (P<0.05) was lower among the cases. After chemotherapy, the mean serum CEA (P<0.05), AFP (P<0.0001) and CA-125 (P<0.05) levels among the cases decreased significantly compared to their pretreatment levels.

CONCLUSIONS

The present study strongly indicates the role of CEA, PRL, AFP, CA-125 and testosterone as important biomarkers in male CRC patients from north India. Further, AFP, CA-125 and CEA may be used to assess the effectiveness of chemotherapy in such patients.

STAT3 activation is required for the antiapoptotic effects of prolactin in cervical cancer cells

BACKGROUND

Prolactin (PRL) has been implicated in the development of different types of cancer. However, signaling pathways might be activated depending on various forms of prolactin receptor (PRLR). JAK/STAT is an important pathway associated with PRL effects. The activation of JAK/STAT pathway might activate antiapoptotic genes that could importantly lead to progression of tumorigenesis. Recently, we have reported that PRL is associated with cell survival by inhibition of apoptosis and the precise activated signaling pathways for this process are still questioned. The purpose of this study was to evaluate the activation of different signaling pathways in response to PRL as well as to identify the induction of antiapoptotic genes.

METHODS

Cervical cancer cell lines HeLa, SiHa and C-33 A were stimulated with PRL (200 ng/mL) for 30 and 60 min and non stimulated cells were used to measure basal protein expression. Inhibition assays were performed by using Jak2 specific inhibitor AG490, either alone or in combination with PRL for 48 h. Western blot were carried out to evaluate protein induction of the different signaling pathways and antiapoptotic proteins. Significant effects were determined by using ANOVA test.

RESULTS

STAT3 was significantly activated in cervical cancer lines in comparison with non-tumorigenic keratinocytes HaCaT. No significant differences were found when analyzing MAPK and PI3K signaling pathways. An increase of antiapoptotic genes Bcl-xl, Bcl-2, survivin and Mcl-1 was observed after stimulus with PRL; however, after inhibition with AG490, the induction of antiapoptotic genes was decreased.

CONCLUSION

Our data suggests that STAT3 is an important signaling pathway activated by PRL in cervical cancer cells and it modulates the induction of antiapoptotic genes. Blocking STAT3 could represent a possible therapeutic strategy in cervical cancer.

Prolactin signaling enhances colon cancer stemness by modulating Notch signaling in a Jak2-STAT3/ERK manner

Prolactin (PRL) is a secretory cytokine produced by various tissues. Binding to the cognate PRL receptor (PRLR), it activates intracellular signaling via janus kinase (JAK), extracellular signal-regulated kinase (ERK) and signal transducer and activator of transcription (STAT) proteins. PRL regulates diverse activities under normal and abnormal conditions, including malignancies. Previous clinical data suggest serum PRL levels are elevated in colorectal cancer (CRC) patients. In this study, we first determined the expression of PRL and PRLR in colon cancer tissue and cell lines. Higher levels of PRLR expression were observed in the cancer cells and cell lines compared with normal colonic epithelial cells. Incubation of colon cancer cells with PRL-induced JAK2, STAT3 and ERK1/2 phosphorylation and increased expression of Jagged 1, which is a Notch-1 receptor ligand. Notch signaling regulates CRC stem cell population. We observed increased accumulation of the cleaved/active form of Notch-1 receptor (Notch intracellular domain) and increased expression of Notch responsive genes HEY1, HES1 and stem cell marker genes DCLK1, LGR5, ALDH1 and CD44. Finally, inhibiting PRL induced JAK2-STAT3 and JAK2-ERK1/2 using AG490 and PD98059, respectively, leads to complete abrogation of Notch signaling, suggesting a role for this pathway in regulating CRC stem cells. Together, our results demonstrate that cytokine signaling induced by PRL is active in colorectal cancers and may provide a novel target for therapeutic intervention.

Prolactin and cancer: Has the orphan finally found a home?

Prolactin has, for long, been associated with galactorrhea and infertility in women while its role in men is largely unknown. Recently, expression of prolactin in various other tissues like the breast, prostate, decidua, and the brain has been recognized. This has led to evaluation of paracrine and autocrine actions of prolactin at these tissues and a possible role in development of various cancers. Increased expression of PRL receptors has also been implicated in carcinogenesis. Breast cancer has the strongest association with increased prolactin and prolactin receptor levels. Prostate cancer also has reported significant association, while the role of prolactin in colorectal, gynecological, laryngeal, and hepatocellular cancers is more tenuous. Prolactin/prolactin receptor pathway has also been implicated in development of resistance to chemotherapy. Thus, the effects of this pathway in carcinogenesis seem widespread. At the same time, they also offer an exciting new approach to hormonal manipulation of cancers, especially the treatment-resistant cancers.

Screening for colorectal cancer

March is national colorectal cancer awareness month. It is estimated that as many as 60% of colorectal cancer deaths could be prevented if all men and women aged 50 years or older were screened routinely. In 2000, Katie Couric's televised colonoscopy led to a 20% increase in screening colonoscopies across America, a stunning rise called the "Katie Couric Effect". This event demonstrated how celebrity endorsement affects health behavior. Currently, discussion is ongoing about the optimal strategy for CRC screening, particularly the costs of screening colonoscopy. The current CRC screening guidelines are summarized in Table 2. Debates over the optimum CRC screening test continue in the face of evidence that 22 million Americans aged 50 to 75 years are not screened for CRC by any modality and 25,000 of those lives may have been saved if they had been screened for CRC. It is clear that improving screening rates and reducing disparities in underscreened communities and population subgroups could further reduce colorectal cancer morbidity and mortality. National Institutes of Health consensus identified the following priority areas to enhance the use and quality of colorectal cancer screening: Eliminate financial barriers to colorectal cancer screening and appropriate follow-up of positive results of colorectal cancer screening. Develop systems to ensure the high quality of colorectal cancer screening programs. Conduct studies to determine the comparative effectiveness of the various colorectal cancer screening methods in usual practice settings. Encouraging population adherence to screening tests and allowing patients to select the tests they prefer may do more good (as long as they choose something) than whatever procedure is chosen by the medical profession as the preferred test.

Constipation-predominant irritable bowel syndrome associated to hyperprolactinemia

Irritable bowel syndrome (IBS) is considered to be a physical disorder that mainly affects the bowel and is clinically characterized by lower abdominal pain or discomfort, diarrhea, constipation (or alternating diarrhea/constipation), gas, bloating, and nausea. According to recent studies, it appears that there is an association with increased prolactin levels in patients suffering from IBS. We report a rare case of regression of IBS symptoms (constipation type) in a 16-year-old female adolescent after receiving cabergoline for treating hyperprolactinemia due to pituitary macroadenoma. Our hypothesis is that increased prolactin levels, for instance due to a pituitary adenoma, may suppress prolactin-releasing peptide release and lead to a reverse feedback interaction, consequently resulting in oversecretion of cholecystokinin, inducing the development of IBS.

Potential of soluble CD26 as a serum marker for colorectal cancer detection

Colorectal cancer is characterized by a low survival rate even though the basis for colon cancer development, which involves the evolution of adenomas to carcinoma, is known. Moreover, the mortality rates continue to rise in economically transitioning countries although there is the opportunity to intervene in the natural history of the adenoma–cancer sequence through risk factors, screening, and treatment. Screening in particular accounted for most of the decline in colorectal cancer mortality achieved in the USA during the period 1975-2000. Patients show a better prognosis when the neoplasm is diagnosed early. Among the variety of screening strategies, the methods range from invasive and costly procedures such as colonoscopy to more low-cost and non-invasive tests such as the fecal occult blood test (guaiac and immunochemical). As a non-invasive biological serum marker would be of great benefit because of the performance of the test, several biomarkers, including cytologic assays, DNA and mRNA, and soluble proteins, have been studied. We found that the soluble CD26 (sCD26) concentration is diminished in serum of colorectal cancer patients compared to healthy donors, suggesting the potential utility of a sCD26 immunochemical detection test for early diagnosis. sCD26 originates from plasma membrane CD26 lacking its transmembrane and cytoplasmic domains. Some 90%–95% of sCD26 has been associated with serum dipeptidyl peptidase IV (DPP-IV) activity. DPP-IV, assigned to the CD26 cluster, is a pleiotropic enzyme expressed mainly on epithelial cells and lymphocytes. Our studies intended to validate this test for population screening to detect colorectal cancer and advanced adenomas are reviewed here.

Biomarkers for colorectal cancer

Colorectal cancer (CRC) is the third most common epithelial malignancy in the world. Since CRC develops slowly from removable precancerous lesions, detection of the lesion at an early stage by regular health examinations can reduce the incidence and mortality of this malignancy. Colonoscopy significantly improves the detection rate of CRC, but the examination is expensive and inconvenient. Therefore, we need novel biomarkers that are non-invasive to enable us to detect CRC quite early. A number of validation studies have been conducted to evaluate genetic, epigenetic or protein markers for identification in the stool and/or serum. Currently, the fecal occult blood test is the most widely used method of screening for CRC. However, advances in genomics and proteomics will lead to the discovery of novel non-invasive biomarkers.

Noninvasive molecular biomarkers for the detection of colorectal cancer

Colorectal cancer (CRC) is the third most common malignancy in the world. Because CRC develops slowly from removable precancerous lesions, detection of the disease at an early stage during regular health examinations can reduce both the incidence and mortality of the disease. Although sigmoidoscopy offers significant improvements in the detection rate of CRC, its diagnostic value is limited by its high costs and inconvenience. Therefore, there is a compelling need for the identification of noninvasive biomarkers that can enable earlier detection of CRC. Accordingly, many validation studies have been conducted to evaluate genetic, epigenetic or protein markers that can be detected in the stool or in serum. Currently, the fecal-occult blood test is the most widely used method of screening for CRC. However, advances in genomics and proteomics combined with developments in other relevant fields will lead to the discovery of novel non invasive biomarkers whose usefulness will be tested in larger validation studies. Here, noninvasive molecular biomarkers that are currently used in clinical settings and have the potential for use as CRC biomarkers are discussed.

Blood markers for early detection of colorectal cancer: a systematic review

BACKGROUND

Despite different available methods for colorectal cancer (CRC) screening and their proven benefits, morbidity, and mortality of this malignancy are still high, partly due to low compliance with screening. Minimally invasive tests based on the analysis of blood specimens may overcome this problem. The purpose of this review was to give an overview of published studies on blood markers aimed at the early detection of CRC and to summarize their performance characteristics.

METHOD

The PUBMED database was searched for relevant studies published until June 2006. Only studies with more than 20 cases and more than 20 controls were included. Information on the markers under study, on the underlying study populations, and on performance characteristics was extracted. Special attention was given to performance characteristics by tumor stage.

RESULTS

Overall, 93 studies evaluating 70 different markers were included. Most studies were done on protein markers, but DNA markers and RNA markers were also investigated. Performance characteristics varied widely between different markers, but also between different studies using the same marker. Promising results were reported for some novel assays, e.g., assays based on SELDI-TOF MS or MALDI-TOF MS, for some proteins (e.g., soluble CD26 and bone sialoprotein) and also for some genetic assays (e.g., L6 mRNA), but evidence thus far is restricted to single studies with limited sample size and without further external validation.

CONCLUSIONS

Larger prospective studies using study populations representing a screening population are needed to verify promising results. In addition, future studies should pay increased attention to the potential of detecting precursor lesions.

Prolactin is an important regulator of intestinal calcium transport

Prolactin has been shown to stimulate intestinal calcium absorption, increase bone turnover, and reduce renal calcium excretion. The small intestine, which is the sole organ supplying new calcium to the body, intensely expresses mRNAs and proteins of prolactin receptors, especially in the duodenum and jejunum, indicating the intestine as a target tissue of prolactin. A number of investigations show that prolactin is able to stimulate the intestinal calcium transport both in vitro and in vivo, whereas bromocriptine, which inhibits pituitary prolactin secretion, antagonizes its actions. In female rats, acute and long-term exposure to high prolactin levels significantly enhances the (i) transcellular active, (ii) solvent drag-induced, and (iii) passive calcium transport occurring in the small intestine. These effects are seen not only in pregnant and lactating animals, but are also observed in non-pregnant and non-lactating animals. Interestingly, young animals are more responsive to prolactin than adults. Prolactin-enhanced calcium absorption gradually diminishes with age, thus suggesting it has an age-dependent mode of action. Although prolactin's effects on calcium absorption are not directly vitamin D-dependent; a certain level of circulating vitamin D may be required for the basal expression of genes related to calcium transport. The aforementioned body of evidence supports the hypothesis that prolactin acts as a regulator of calcium homeostasis by controlling the intestinal calcium absorption. Cellular and molecular signal transductions of prolactin in the enterocytes are largely unknown, however, and still require investigation.