p53 status and human papillomavirus infection in Thai women with cervical carcinoma.

Loss of p53 function has been implicated in a wide variety of human malignacies. Many studies suggest that in cervical carcinoma p53 function is inactivated either by gene mutation or by complex formation with E6 oncoprotein product of high-risk human papillomavirus (HPV). The aim of this study was to determine the status of HPV infection and p53 gene mutation as well as their correlation in cervical carcinomas. Formalin-fixed paraffin-embedded tissues of 12 cervicitis, 21 cervical intraepithelial neoplasia grade 3 (CIN 3) and 17 squamous cell carcinomas were determined for the presence of HPV using polymerase chain reaction (PCR) amplification and dot blot hybridization. The status of p53 mutations in exons 5-8 was evaluated by polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) and confirmed by direct nucleotide sequencing. HPV infections were detected in all CIN 3 and squamous cell carcinomas (100%). Mutations of p53 were present in 3 of 38 HPV-positive samples: one with an ATG-->TTG transversion (Met-->Leu) in codon 237 of exon 7; and the others with a TGC-->TGG transversion (Cys-->Trp) in codon 242 of exon 7, and a CGT-->CCT transversion (Arg-->Pro) in codon 273 of exon 8, respectively. Our findings show that the frequency of p53 mutation is low in primary cervical carcinoma and that the p53 gene mutation and HPV infection are not mutually exclusive events in the development of cervical cancer. Thus, other genetic events independent of p53 inactivation may also significantly contribute to the carcinogenesis of the uterine cervix.

Detection and typing of human papillomavirus in cervical intraepithelial neoplasia grade III in Thai women.

Infection of human papillomaviruses (HPVs) has been shown to play an important role in the development of cervical cancer from precancerous lesions known as cervical intraepithelial neoplasia (CIN-I, CIN-II and CIN-III). In Thailand, cervical cancer is the most common cancer in women. Fifty tissue samples diagnosed as CIN-III and 50 tissues of normal histopathologic appearance as controls were examined for the presence of HPV-DNA and HPV typing using PCR and dot hybridization (DH) methods. All specimens used in this study were formalin-fixed paraffin embedded tissues. HPV-DNA was detected in 74% (37/50) of CIN-III and 6% (3/50) of the control group giving a crude odd ratio of 44.58 (95% confidence interval of 15.2-130). Among the CIN-III group, the most prevalent type was HPV-16; 48.65% (18/37) followed by HPV-18; 16.2% (6/37) and HPV-33; 10.8% (4/37). Mixed infection was identified in 4 specimens, ie HPV-6/16, HPV-16/18, HPV-16/33, and HPV-16/18/33. Twelve samples were untyped. In the control group, only one sample (33.3%) was detected to contain HPV-6 DNA and the remaining ones were untyped. Our results revealed infection with HPV, especially HPV-16 and HPV-18, to be strongly associated with CIN-III in Thai women.

Maternal and neonatal effects of single-dose epidural anesthesia with lidocaine and morphine for cesarean delivery.

Two per cent lidocaine (18-20 ml) with epinephrine 1:200,000 plus 4 mg of morphine was given as a single epidural injection over 3 minutes for elective cesarean section in 60 healthy mothers at term. It provided effective, safe and adequate analgesia in the postoperative period. There was no evidence of neonatal depression related to the epidural morphine as judged by Apgar scores at 1 and 5 minutes and umbilical venous pH at birth. Maternal and umbilical venous levels of morphine were measured and found to be low at birth. However, this study was done only in healthy mothers not in labor and having a term fetus. We do not recommend using this technique in complicated obstetric patients.

Detection and typing of human papillomavirus in cervical cancer in the Thai.

One hundred formalin-fixed paraffin embedded tissues with histopathologic diagnosed invasive cervical cancer (squamous cell carcinoma) were examined for the presence of HPV-DNA by polymerase chain reaction (PCR) using L1-consensus primers. The results indicated that 82 out of 100 (82%) samples were positive for HPV-DNA. Among the positive samples, 50 samples (61%) were typed by dot hybridization technique (DH). HPV-16 was the dominant type (42.68%), followed by HPV-18 (20.73%) and HPV-33 (3.66%). There were double infection of HPV-16 and 18 in 5 (6.1%) samples. None of HPV-6 and 11 were detected in this study. This finding suggests that HPV infection is an important etiologic factor for the development of cervical cancer especially the infection with high risk types, i.e., HPV-16 and 18.

Male sexual behavior as risk factor in cervical cancer.

Risk factors of male sexual behavior for squamous cell carcinoma of the uterine cervix were studied in Thai women at Chulalongkorn Hospital, Bangkok, Thailand, using an unmatched case-control design. A total of 93 case husbands and 169 control husbands were recruited in the study. Case husbands are prone to have more sexual partners than the control and have an age of first sexual intercourse earlier than the controls. More husbands of cases than of controls had history of prostitute visits in their life with the odds ratio of 9.42. Prostitute visit is a main risk factor, irrespective of whether the husband had a history of sexually transmitted diseases or not. Condom use in sexual intercourse with prostitutes seemed to have a protective effect for their wives in decreasing risk of cervical cancer. This study supports the infectious and venerally transmitted character of cervical cancer and indicates that the other measure of preventing and controlling cervical cancer in women is to educate and prevent men from having high risk sexual behavior.