Targeted Therapy in Thyroid Cancer: State of the Art

Thyroid cancer typically has a good outcome following standard treatments, which include surgery, radioactive iodine ablation for differentiated tumours and treatment with thyrotropine hormone-suppressive levothyroxine. Thyroid cancers that persist or recur following these therapies have a poorer prognosis. Cytotoxic chemotherapy or external beam radiotherapy has a low efficacy in these patients. 'Target therapy' with tyrosine kinase inhibitors (TKIs) represent an important therapeutic option for the treatment of advanced cases of radioiodine refractory (RAI-R) differentiated thyroid cancer (DTC), medullary thyroid cancer (MTC) and possibly for cases of poorly differentiated (PDTC) and anaplastic thyroid cancer (ATC). In the last few years, several TKIs have been tested for the treatment of advanced, progressive and RAI-R thyroid cancers and some of them have been recently approved for use in clinical practice: sorafenib and lenvatinib for DTC and PDTC; vandetanib and cabozantinib for MTC. The objective of this overview is to present the current status of the treatment of advanced DTC, MTC, PDTC and ATC with the use of TKIs by describing the benefits and the limits of their use. A comprehensive analysis and description of the molecular basis of these drugs and the new therapeutic perspectives are also reported. Some practical suggestions are also given for the management to the potential side-effects of these drugs.

In silico and in vitro analysis of rare germline allelic variants of RET oncogene associated with medullary thyroid cancer

Germline and somatic RET oncogene mutations are found in 98% hereditary and 40% sporadic medullary thyroid carcinomas. Our aim was to analyse by in silico and in vitro assays the transforming activity of six rare RET mutations (T338I, V648I, M918V, A883T, S904F and M848T). Six known RET mutations were used as controls. The in silico analysis showed the highest score value (i.e. 65) for S904F, M848T, M918T and C634R, whereas L790F, G691S, T338I and V648I had 0 score. Intermediate score values were obtained by A883T (score=55), M918V, V804M and Y791F (score=15). The in vitro focus formation assay showed that cells transfected with S904F, M918T, M848T or C634R generated the largest number of focus formation units (FFU). Intermediate numbers of FFU were observed in cells transfected with M918V, V804M, Y791F or A883T, while cells transfected with L790F, G691S, T338I or V648I showed a number of FFU similar to control cells. A positive correlation between the in silico score and in vitro FFU was found (P=0.0005). Only cells transfected with M918T or C634R grew faster and generated higher number of colonies in soft agar than control cells. However, the cells that were transfected with V804M produced an intermediate number of colonies. In conclusion, two of the six rare RET mutations, S904F and M848T possessed a relatively high transforming activity but a low aggressiveness; the other four mutations T338I, V648I, M918V and A883T were low or non-transforming, and their ability to induce tumoural transformation might be related to particular genetic conditions.

Myasthenia gravis during low-dose IFN-alpha therapy for chronic hepatitis C

We describe the case of a 56-year-old man who had high aminotransferase levels and anti-hepatitis C virus (HCV) antibodies. He underwent liver biopsy and biochemical screening to evaluate whether he would benefit from interferon (IFN) treatment. The patient was discharged with a diagnosis of HCV-related active chronic hepatitis, skin porphyria, and type 2 diabetes. On December 5, 1995, he began therapy with recombinant IFN-alpha at a dose of 3 MIU three times a week. He stopped this therapy in February 1996 because of asthenia, diplopia, headache, and anxiety. During IFN therapy, he had normal aminotransferase levels and no detectable HCV RNA, a condition that persists to the present. Between March and May 1996, the patient was admitted several times to a neurology clinic, where myasthenia gravis was diagnosed and treatment with pyridostigmine and cyclosporine was initiated. This case and others indicate that caution should be exercised in administering IFN because low doses can be correlated with myasthenia gravis in patients without malignancies.

Re-differentiation of thyroid carcinoma cell lines treated with 5-Aza-2'-deoxycytidine and retinoic acid

We studied cell growth rate, mechanisms of growth inhibition, phenotype re-differentiation, expression of RARalpha, beta, gamma and differentiation thyroid genes before and after combined treatment with 5-Aza-CdR and RA (5-Aza/RA) of human thyroid carcinoma cell lines (FRO, WRO, TT). Furthermore, the activity and localization of the re-expressed sodium-iodide-symporter (NIS) protein was analyzed. After 5-Aza/RA treatment, all cell lines showed a significant reduction in cell growth. This was associated with apoptosis in the TT, with inhibition of cell proliferation in the WRO, and with cell cycle impairment in FRO and WRO. FRO and WRO treated with 5-Aza/RA lost the ability to grow in soft agar. FRO re-expressed thyroid transcription factor-1 and thyroglobulin, TT and WRO re-expressed PAX-8 and FRO and TT re-expressed RARbeta and NIS mRNA. Despite this expression, they were unable to take up iodine: a cytoplasmic localization of NIS protein was demonstrated in FRO. In conclusion, besides a significant reduction in cell growth rate and in the ability to grow in soft agar, treatment with 5-Aza/RA partially re-differentiated FRO and induced expression of NIS mRNA and protein in FRO and TT, but this treatment was unable to restore the functional activity of NIS, likely because it was located into the cytoplasm without reaching the plasma membrane.

A rare case of brainstem encephalitis by Listeria monocytogenes with isolated mesencephalic localization. Case report and review

We describe a case of brainstem infection by Listeria monocytogenes with right oculomotor palsy and lip drop, facial hypoesthesia, left arm paresthesia, positive blood culture, and sterile liquor in a 63-year-old man. Magnetic resonance imaging revealed an isolated mesencephalic lesion. Localization of this kind accounted for 3% of 111 cases reviewed.

Classical point mutations of RET, BRAF and RAS oncogenes are not shared in papillary and medullary thyroid cancer occurring simultaneously in the same gland

BACKGROUND

Papillary (PTC) and medullary (MTC) thyroid carcinomas represent two distinct entities, but quite frequently, they may occur simultaneously.

AIM

To provide genetic analysis of PTC and MTC occurring in the same patient (PTC/MTC) to elucidate their origin.

METHODS

Sequencing analysis of RAS, BRAF and RET oncogenes hot spots mutations in tumoral and normal tissues of 24 PTC/MTC patients.

RESULTS

Two of 24 patients (8.3 %) were affected by familial MTC (FMTC) harboring RET germline mutations in all tissues. Eight of 22 (36.4 %) sporadic cases did not show any somatic mutation in the three tissue components. Considering the MTC component, 10/22 (45.4 %) patients did not show any somatic mutation, 7 of 22 (31.8 %) harbored the M918T RET somatic mutation and 4/22 (18.2 %) presented mutations in the H-RAS gene. In an additional case (1/22, 4.6 %), H-RAS and RET mutations were simultaneously present. Considering the PTC component, 1 of 24 (4.2 %) patients harbored the V600E BRAF mutation, 1 of 24 (4.2 %) the T58A H-RAS mutation and 1 of 24 (4.2 %) the M1T K-RAS mutation, while the remaining PTC cases did not show any somatic mutation. In one case, the MTC harbored a RET mutation and the PTC a BRAF mutation. None of the mutations found were present in both tumors.

CONCLUSIONS

To our knowledge, this is the first study analyzing a possible involvement of RET, BRAF and RAS oncogene mutations in PTC/MTC. These data clearly suggest that the classical activating mutations of the oncogenes commonly involved in the pathogenesis of PTC and MTC may not be responsible for their simultaneous occurrence.

Pernicious anemia during IFN-alpha treatment for chronic hepatitis C

Some latent diseases, such as immune disorders, can appear during interferon-alpha (IFN-alpha) therapy. These disorders are difficult to predict because of their low prevalence in the general population. We describe a case of pernicious anemia (PA) in a patient affected by chronic hepatitis C and macrocytosis during IFN-alpha therapy. Hemoglobin (Hb) concentration reached 7.3 g/dl. Anti-intrinsic factor (IF) antibodies were present, but not antiparietal cell antibodies (APCA). Suspension of IFN-alpha and administration of vitamin B(12) resulted in normal Hb concentrations. This case is the first instance of early PA (at the second month of IFN therapy) in a patient affected by chronic hepatitis C. The only other case of PA in a patient affected by hepatitis C virus (HCV) infection occurred during the second year of maintenance IFN therapy. We recommend that particular attention be paid to such clinical and laboratory conditions as macrocytosis in administering IFN-alpha therapy for chronic hepatitis C.

Case Report: Hemolytic Anemia During Pegylated IFN-α2b Plus Ribavirin Treatment for Chronic Hepatitis C: Ribavirin Is Not Always the Culprit

A 53-year-old woman admitted to our department for histologically proven chronic hepatitis C had previously been treated with pegylated interferon-alpha2b (PEG-IFN) plus ribavirin. Combination therapy had been withdrawn after 5 weeks because of severe anemia (hemoglobin 8.2 g/dl) despite a reduction in ribavirin dose. A second liver biopsy showed moderate chronic hepatitis with portoportal and portocentral bridges (Ishak score: grading 14/18, staging 4-5/6). Consequently, the patient was retreated with 1.5 microg/kg body weight weekly PEG-IFN and 1000 mg/day ribavirin. Ribavirin was withdrawn about 3 months later because of anemia. After 1 month of PEG-IFN alone, hemoglobin had decreased further to reach 7.9 g/dl; consequently IFN was stopped. An elevated reticulocyte count, indirect bilirubin concentration, and lactic dehydrogenase (LDH) concentration, and a positive direct Coombs test (IgG3, C3d also for panagglutinant irregular antibodies on eluate) led us to diagnose autoimmune hemolytic anemia (AHA). The patient received 1 mg/kg body weight/day prednisone, and all parameters normalized within 20 days. This is the first case of IFN-related AHA during PEG-IFN plus ribavirin therapy. Physicians should be aware that PEG-IFN can be the cause of AHA during a ribavirin-containing regimen for chronic hepatitis C.

Celecoxib, a cyclooxygenase-2 inhibitor, potentiates the chemotherapic effect of vinorelbine in the medullary thyroid cancer TT cell line

We analyzed the in vitro effects of celecoxib, a COX-2 inhibitor, and determined if celecoxib can sensitize a human MTC-derived cell line (TT) to chemotherapeutics. We found that celecoxib induced apoptosis in TT cells and decreased drug efflux by reducing the expression of MDR-1 mRNA, which codes for the drug efflux pump P-gp. We also observed that TT cells were 10-fold more resistant to doxorubicin than to vinorelbine, mimicking what can be observed in clinical practice. In addition, we found that the combination of celecoxib and vinorelbine, but not doxorubicin, induced a significant reduction in cell viability and a significant increase in apoptosis. In conclusion, we showed that celecoxib was able to enhance the chemotherapeutic effect of vinorelbine. A clinical trial exploring the in vivo activities of celecoxib in MTC patients who cannot benefit from available treatments would be desirable, taking into account the possible risks of cardiovascular effects of this drug.

Retinoic acid receptor beta2 re-expression and growth inhibition in thyroid carcinoma cell lines after 5-aza-2'-deoxycytidine treatment

The treatment of both undifferentiated and de-differentiated thyroid tumors, which are unresponsive to radioiodine, represents one of the biggest challenges for thyroidologists. The aim of the present study was to investigate in vitro the methylation status of retinoic acid receptors (RAR)beta2 promoter and the effect of the demethylating agent 5-aza-2'-deoxycytidine (5-Aza-CdR) on 5 human thyroid cancer cell lines. The methylation status of RARbeta2 promoter was analyzed by methylation-specific PCR. The effect of 5-Aza-CdR on cell growth and apoptosis was evaluated by cell counting, enzymelinked immunosorbent assay tests and fluorescence-activated cell sorting analysis, while the effect on the expression of RAR and thyroid-specific genes was measured by qualitative and quantitative RT-PCR. Methylation of RARbeta2 promoter was present only in ARO cells. 5-Aza-CdR determined growth inhibition in all cell lines, probably due to apoptosis in WRO, NPA, and ARO cells, and to inhibition of DNA synthesis in TT cells. Treatment with 5-Aza-CdR induced the expression of RARbeta mRNA in ARO and FRO cells, a slight increase of the expression of Tg, TPO and thyroid trancription factor 1 (TTF-1) mRNA and the new expression of low levels of NIS in TT cells. A significant increase of TTF-1 mRNA in FRO cells was also observed. In this study we demonstrated that RARbeta2 promoter was methylated in ARO cell line. However, the 5-Aza-CdR treatment induced RARbetamRNA expression not only in ARO but also in FRO and TT cell lines, whose RARbeta2 promoter was unmethylated. A significant reduction of cell growth, but not cell re-differentiation, was also observed after 5-Aza-CdR treatment.

A case of paracoccidioidomycosis: experience with long-term therapy

We describe long-term therapy for paracoccidioidomycosis occurring in a 61-year-old house-painter from Venezuela. The diagnostic examinations made in South America had shown pulmonary granulomatous lesions and an osteolytic pattern of the left knee that had been considered suspect of malignant disease with an indication for limb amputation. With the aid of fine needle aspiration biopsy (FNAB) and culture examination we diagnosed an osteomyelitis by Paracoccidioides brasiliensis and initiated therapy with itraconazole, 400 mg per day, reduced to 200 mg per day after 2 months. At the end of 2 years of drug therapy, we observed complete regression of the pulmonary lesions and of the osteolytic area of the left knee. Moreover, we have periodically observed our patient to verify his clinical development and he is still in good health. We suggest that this pathology be considered in differential diagnosis of leprosy, tuberculosis, leishmaniasis, and systemic mycoses, even in non-endemic areas.

Prevalence of hepatitis C virus genotypes in southern Italy

HCV is ubiquitous. In 50% of all cases it causes chronic hepatitis that often evolves into liver cirrhosis and hepatocellular carcinoma. Recently HCV has been classified in 5 genotypes by Okamoto. The purpose of this study is to evaluate the prevalence of 5 genotypes in Campania, a region of southern Italy, where the prevalence of anti-HCV antibodies ranges from 0.87 to 4%, and to evaluate the correlation between the HCV genotypes and the severity of histological damage. One-hundred- and-thirty-five anti-HCV positive patients were enrolled and tested by PCR to identify HCV-RNA. One-hundred-and-twenty-four patients resulted HCV-RNA positive. Genotyping was performed as described by Okamoto et al. with minor modifications of the specific primer to type III proposed by Silini et al. Eight patients were negative for all genotypes. Eight patients were positive for type I(1a), 61 for type II(1b), 39 for type III(2a), 11 for type IV(2b) and 1 for type V(3a). In 4 cases two different genotypes were present in the same sample [II(1b)-IV(2b), III(2a)-II(1b) twice, III (2a)-IV(2b)]. Histological evaluation of liver damage showed: CPH (22 cases), minimal CAH (56), severe CAH (31) and liver cirrhosis (15). There was no statistically significant correlation between the 5 genotypes and the severity of histological damage. Data on the prevalence of genotype II (1b) in Italy are similar to those reported for other European countries. The prevalence of genotypes in southern Italy is similar to that reported in the population of northern Italy.

Liver echinococcosis in a renal transplant patient: a particularly intriguing case report

A renal transplant patient was admitted to his local town hospital with suspected acute pancreatitis (jaundice, abdominal pain and fever). Despite intensive medical care (including endoscopic retrograde cholangiopancreatography) and several negative radiological exams (including computed tomography and nuclear magnetic resonance spectroscopy), no certain diagnosis could be made. After 1 month, the patient was transferred to our facility, where a new sonography was performed, as a prelude to a liver biopsy, which showed the presence of multiple fluid-filled cysts (up to 8 cm), strongly suggestive of hydatid liver disease. Empirical therapy with albendazole was started, and cyclosporine dosage, previously reduced, was restored. This enabled a prompt resolution of the disease and the progressive fibrous evolution of the cysts over the 18-month follow-up period, with no damage to renal function, which remained stable.

Circulating miR-26b-5p and miR-451a as diagnostic biomarkers in medullary thyroid carcinoma patients

PURPOSE/METHODS

The determination of tumour biomarkers is paramount to advancing personalized medicine, more so in rare tumours like medullary thyroid carcinoma (MTC), whose diagnosis is still challenging. The aim of this study was to identify non-invasive circulating biomarkers in MTC. To achieve this goal, paired MTC tissue and plasma extracellular vesicle samples were collected from multiple centres and microRNA (miRNA) expression levels were evaluated.

RESULTS

The samples from a discovery cohort of 23 MTC patients were analysed using miRNA arrays. Lasso logistic regression analysis resulted in the identification of a set of circulating miRNAs as diagnostic biomarkers. Among them, miR-26b-5p and miR-451a, were highly expressed and their expression decreased during follow-up in disease-free patients in the discovery cohort. Circulating miR-26b-5p and miR-451a were validated using droplet digital PCR in a second independent cohort of 12 MTC patients.

CONCLUSION

This study allowed the identification and validation of a signature of two circulating miRNAs, miR-26b-5p and miR-451a, in two independent cohorts reporting a significant diagnostic performance for MTC. The results of this study offer advancements in molecular diagnosis of MTC proposing a novel non-invasive tool to use in precision medicine.

[AIDS and the community. Preliminary data of an epidemiological study]

An epidemiological study into the prevalence and incidence of anti-H.I.V. antibody seropositivity in closed communities produced preliminary data on 746 subjects, the majority of whom admitted potentially dangerous behaviour. These results demonstrated that residence in a closed community in which one can limit the use of drugs and sexual contacts reduces the risk of infection.

[HCV and HBV infection in 3 communities in the Neapolitan area]

Using the antibody to HCV and HBc (anti-HCV, anti-HBc), we studied the prevalence of Hepatitis C and B virus in three groups: intravenous drug abusers, subjects lodging in huts and elderly clergymen. Statistical analysis was carried out by chi-square and Fisher's exact tests. Our results show statistical significance for anti-HCV seroprevalence among the three groups, while anti-HBc doesn't differ. These preliminary data seem to show that the two viruses have different ways of transmission.

[Clinical and diagnostic considerations on a case of pancreatic plasmacytoma]

An unusual case of obstructive jaundice due to metastatic pancreatic plasmacytoma is described. Initially post-transfusion hepatitis was suspected in the patient who suffered from multiple myeloma (IgA) and had received numerous transfusions for severe anemia. Clinical and laboratory findings indicated obstructive jaundice and the ecographic examination showed a dishomogeneous mass at the level of the pancreas. The investigators suggest that after this type of ecographic finding a percutaneous biopsy should be performed eliminating exploratory laparotomy, a high risk procedure in this type of patient, and eventually radiotherapy should be initiated since this type of tumor is radiosensitive.

[Unusual ultrastructural findings in a case of asymptomatic primary biliary cirrhosis]

The investigators report an ultrastructural study of a case of primary biliary cirrhosis histologically in stage II (Scheuer), a rare disease which has not been investigated extensively at the ultrastructural level. Biliary canaliculi are dilated and microvilli are scarce. Large granular formations are observed in the perisinusoidal cytoplasm. The plasma membrane between adjacent hepatocytes appears convoluted. The ultrastructural alterations of the biliary canaliculi which we observed have been described in the literature in cholestatic patients and ascribed to cholestasis. Our patients, however, has never suffered episodes of jaundice or itching and has no histological signs indicating cholestasis. We suggest that these are precocious alterations which precede the appearance of clinical and histological signs of cholestasis. It is necessary to study other cases in order to evaluate the significance of the large granular formations and the changes observed in the plasma membrane.

Seroprevalence of HBV and HCV markers among intravenous drug abusers and subjects affected by chronic active hepatitis

In order to investigate the seroprevalence of HBV and HCV in neapolitan area, we studied blood specimens of 180 IVDAs, 115 CAH patients and 72 healthy subjects using hepatitis B core (anti-HBs) and hepatitis C antibody (anti-HCV). High frequency of anti-HBs (80.9%) and strong association with an unexpected seroprevalence of anti-HCV (67%) was found in CAH patients. Our study does not explain these results, but suggest either a possible inference between both viruses or that serum from CAH subjects contains a component that gives false positivity.

Presence of delta antigen in liver biopsies of HBsAg positive patients with chronic liver diseases living in the Naples area

In a study of the presence of delta-Ag in liver biopsies of HBsAg positive patients with chronic liver diseases living in the Naples area, delta-Ag has been found only in patients with HBsAg positive chronic active hepatitis and in none of HBsAg positive patients with other liver diseases including those with chronic persistent hepatitis. The data obtained support the hypothesis that the simultaneous infection with HBV and delta-agent, and superinfection with delta-agent in HBsAg positive patients predispose the outcome of chronic hepatitis.