RESUMO
Small cell carcinoma of cervix (SCCC) is a rare disease with highly aggressive behaviour and is pathologically hard to diagnose. In this study, the clinicopathological features, diagnosis, treatment and prognosis of the condition were examined. Clinical records and follow-up data of 7 cases of SCCC were retrospectively studied. Our results showed that five non-recurrent cases initially presented irregular vaginal bleeding or increased apocenosis of varying degrees. Pathological examination revealed that the stroma was diffusely infiltrated with small monomorphous cells ranging from round to oval shape. Three cases were immunohistochemically confirmed. One case was accompanied with squamous cell cancer. Of the 7 cases, one case was classified as stage I b1, two stage I b2, one stage IIa, one stage IIb, and one stage IIIb. On the basis of their stages of condition, one subject with stage III b underwent chemotherapy, and one with stage Ib2 received extensive hysterectomy plus pelvic lymphadenectomy, while the other 5 cases were treated by extensive hysterectomy and pelvic lymphadenectomy in combination with pre- and/or post-operative adjuvant chemotherapy and radiotherapy. Of the 7 patients, 4 had relapse-free survival of 14, 14, 16 and 28 months respectively. It is concluded that SCCC is an aggressive tumor with propensity for early pelvis lymph node metastases. Early-stage patients should be treated by extensive hysterectomy and pelvic lymphadenectomy in combination with pre- and/or post-operative adjuvant chemotherapy and radiotherapy.
RESUMO
By using a yeast two-hybrid system, a yeast two-hybrid bait vector was constructed and identified for screening of the HPV18 E6-interacting proteins, and its effects on the growth of yeast cells and the activation of reporter genes were investigated. Total mRNA extracted from Hela cells was reversely transcribed into cDNA. Fragment of HPV18 E6 cDNA was amplified using RT-PCR and directly ligated to the pGBKT7 vector. The recombinant plasmid was confirmed by restriction endonuclease analysis and DNA sequencing. The recombinant pGBKT7-HPV18 E6 plasmid and empty pGBKT7 vector were transformed into the yeast cell AH109, respectively. After they were cultured respectively in YPDA liquid medium and nutrition-deficient culture medium, their toxicity and transcriptional activation were tested by both the phenotype assay and the color assay. The bait plasmid HPV18 E6 was successfully obtained. After being cultured in YPDA liquid medium for 16h, the A (600 nm) values of two yeast fluids were 0.98+/-0.03 and 0.99+/-0.02, respectively. The recombinant pGBKT7-HPV18 E6 plasmid and empty pGBKT7 vector could grow to white colonies on SD/-Trp/X-alpha-gal plates, while no colony could survive on SD/-His/-Trp/X-alpha-gal, SD/-Ade/-Trp/X-alpha-gal plates, indicating that the bait plasmid pGBKT7-HPV18 E6 was constructed successfully and expressed correctly, and could not activate the transcription of reporter gene alone. The yeast two-hybrid GAL4 system 3 can be utilized to find HPV18 E6 interacting proteins.
RESUMO
A novel insulin analog, PIns, with N-terminal Arg-4, Pro-3, Lys-2, Pro-1extension at human regular insulin B-chain was acquired through gene engineering. Preproinsulin for PIns was cloned and expressed using a bacterial expression system at a high level (72.1%) as fusion protein carrying a modified thioredoxin N-terminal region (1-21) linked to N-terminus of proinsulin by a lysine residue. Purified fusion protein was refolded and converted into PIns by a single enzymatic reaction. After PIns was purified, the homogeneity of it was characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis, isoelectronic focusing electrophoresis, amino acid composition analysis and mass spectrometry methods. A decreased tendency of self-association of PIns as compared with regular insulin was demonstrated by the size exclusion HPLC analysis. When subcutaneously administrated into normal rats, the PIns showed a faster rate of onset of action and a shorter duration of action compared with regular insulin, similar to the pharmacokinetic characteristics of insulin Lispro. These results showed that PIns is a rapid insulin analog. Furthermore, the N-terminal Arg-4, Pro-3, Lys-2, Pro-1extension at insulin B-chain can be excised by DPPIV and recombinant peptidase with DPPIV-like activities. It is suggested that PIns serves as an artificial insulin precursor and can be transformed to regular insulin in vivo due to the truncation of N-terminal sequence of PIns B-chain by DPPIV.
