Comparison of filgrastim and lenograstim in pediatric solid tumors

G-CSF, the guardian of granulopoiesis

A considerable amount of continuous proliferation and differentiation is required to produce daily a billion new neutrophils in an adult human. Of the few cytokines and factors known to control neutrophil production, G-CSF is the guardian of granulopoiesis. G-CSF/CSF3R signaling involves the recruitment of non-receptor protein tyrosine kinases and their dependent signaling pathways of serine/threonine kinases, tyrosine phosphatases, and lipid second messengers. These pathways converge to activate the families of STAT and C/EBP transcription factors. CSF3R mutations are associated with human disorders of neutrophil production, including severe congenital neutropenia, neutrophilia, and myeloid malignancies. More than three decades after their identification, cloning, and characterization of G-CSF and G-CSF receptor, fundamental questions remain about their physiology.

Development of Wolffia arrhiza as a Producer for Recombinant Human Granulocyte Colony-Stimulating Factor

To date, the expression of recombinant proteins in transgenic plants is becoming a powerful alternative to classical expression methods. Special efforts are directed to the development of contained cultivation systems based on cell culture or rhyzosecretion, which reliably prevents the heterologous DNA releasing into the environment. A promising object for the development of such systems is the tiny aquatic plant of Wolffia arrhiza, which can be used as a dipped culture in bioreactors. Herein we have expressed the human granulocyte colony-stimulating factor (hG-CSF) in nuclear-transformed Wolffia. The nucleotide sequence of hG-CSF was optimized for expression in Wolffia and cloned into the vector pCamGCSF downstream of double CaMV 35S promoter. Wolffia plants were successfully transformed and 34 independent transgenic lines with hG-CSF gene were obtained, PCR and Southern blot analysis confirmed the transgenic origin of these lines. Western blot analysis revealed accumulation of the target protein in 33 transgenic lines. Quantitative ELISA of protein extracts from these lines showed hG-CSF accumulation up to 35.5 mg/kg of Wolffia fresh weight (0.194% of total soluble protein). This relatively high yield holds promise for the development of Wolffia-based expression system in strictly controlled format to produce various recombinant proteins.

Risk factors for poor mobilization in solid tumors: How effectively can we mobilize patients with solid tumors?

BACKGROUND

In the literature, risk factors for poor mobilization were tried to identify. However, most of the studies consisted heterogeneous group of patients including both hematologic and oncologic malignancies. In this study, we aimed to identify the risk factors for poor mobilization in adults with solid tumors.

METHODS

We enrolled 49(47 men, 2 women) adult patients with solid tumor who were mobilized between September 2007 and February 2017. All the mobilization procedures were performed with G-CSF(10μg/kg/day) with chemotherapy. Mobilization insufficiency was defined as peripheral blood CD34+stem cell number less than 10/μl and/or total collected CD34+cells less than 2.5×10 ⁶/kg.

RESULTS

The patients were divided into two groups, patients with successful mobilization at the first attempt(group 1, 36 patients,73.5%) and poor mobilizers (group 2, 13 patients 26.5%). Second and third mobilization attempt was needed in 11 and 2 patients, respectively. The median number of CD34+cells collected was 7,08×10⁶/kg(0,6-19) with a median 4(1-6) apheresis. There was no statistical difference between two groups in terms of patient's and mobilization characteristics. Only number of CD 34+stem cells collected was statistically different (median 9,07×10⁶/kg CD34+cells in group 1 versus 2,14×10⁶/kg in group 2, p<0.05). The only possible risk factor that we could define was presence of organ metastasis.

CONCLUSIONS

Since several methods and new drugs are available for peripheral stem cell collecting, risk factors should be identified clearly in adult population with solid tumors. So multicenter studies should be constructed for resolving this problem.

Which one is more effective, filgrastim or lenograstim, during febrile neutropenia attack in hospitalized patients with solid tumors?

BACKGROUND

Chemotherapy-induced febrile neutropenia (FN) with solid tumors causes mortality and morbidity at a significant rate. The purpose of this study was to compare the effects of filgastrim and lenograstim started with the first dose of antibiotics in hospitalized patients diagnosed with FN.

MATERIALS AND METHODS

Between February 2009 and May 2012, 151 patients diagnosed with FN were evaluated, retrospectively. In those considered appropriate for hospitalization, convenient antibiotic therapy with granulocyte colony stimulating factors was started within first 30 minutes by completing necessary examinations in accordance with FEN guide recommendations.

RESULTS

In this study, 175 febrile neutropenia attacks in 151 patients were examined. Seventy three of the patients were male and 78 were female. The average age was 53.6 and 53.6, respectively. The most common solid tumor was breast carcinoma in 38 (25%) . One hundred and five FN patients (58%) were those who received granulocyte colony stimulating factors as primary prophylaxis.

CONCLUSIONS

While studies comparing both drugs generally involve treatments started for prophylaxis, this study compared the treatment given during the febrile neutropenia attack. Compared to lenograstim, filgastrim shortens the duration of hospitalization during febrile neutropenia attack by facilitating faster recovery with solid tumors.